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• 1. [Article] Toward More Robust Extreme Flood Prediction by Bayesian Hierarchical and Multimodeling

  Flood information, especially extreme flood, is necessary for any large hydraulic structure design and flood risk management. Flood mitigation also requires a comprehensive assessment of flood risk and ...

  Citation × Citation Citation Abstract Copy Title: Toward More Robust Extreme Flood Prediction by Bayesian Hierarchical and Multimodeling Author: Yan, Hongxiang, Moradkhani, Hamid Year: 2016 Flood information, especially extreme flood, is necessary for any large hydraulic structure design and flood risk management. Flood mitigation also requires a comprehensive assessment of flood risk and an explicit quantification of the flood uncertainty. In the present study, we use a multimodel ensemble approach based on Bayesian model averaging (BMA) method to account for model structure and distribution uncertainties. The usefulness of this approach is assessed by a case study over the Willamette River Basin (WRB) in Pacific Northwest, USA. Besides the standard log-Pearson Type III distribution, we also identified that the generalized extreme value and three-parameter lognormal distributions were both potential distributions in WRB. Three different statistical models, including the Bulletin-17B quantile model, index-flood model, and spatial Bayesian hierarchical model, were considered in the study. The BMA method is then used to assign weights to different models, where better performing model receives higher weights. It was found that the major uncertainty in extreme flood prediction is contributed by model structure, while the choice of distribution plays a lesser important role in quantification of flood uncertainty. The BMA approach provides a more robust extreme flood prediction than any single model. Title: Toward More Robust Extreme Flood Prediction by Bayesian Hierarchical and Multimodeling Author: Yan, Hongxiang, Moradkhani, Hamid Year: 2016 Flood information, especially extreme flood, is necessary for any large hydraulic structure design and flood risk management. Flood mitigation also requires a comprehensive assessment of flood risk and an explicit quantification of the flood uncertainty. In the present study, we use a multimodel ensemble approach based on Bayesian model averaging (BMA) method to account for model structure and distribution uncertainties. The usefulness of this approach is assessed by a case study over the Willamette River Basin (WRB) in Pacific Northwest, USA. Besides the standard log-Pearson Type III distribution, we also identified that the generalized extreme value and three-parameter lognormal distributions were both potential distributions in WRB. Three different statistical models, including the Bulletin-17B quantile model, index-flood model, and spatial Bayesian hierarchical model, were considered in the study. The BMA method is then used to assign weights to different models, where better performing model receives higher weights. It was found that the major uncertainty in extreme flood prediction is contributed by model structure, while the choice of distribution plays a lesser important role in quantification of flood uncertainty. The BMA approach provides a more robust extreme flood prediction than any single model. Close

• 2. [Article] Ancient Cataclysmic Floods in the Pacific Northwest: Ancestors to the Missoula Floods

  Ancient Cataclysmic Floods were the Ice Age Floods that left erosional and depositional features and preceded the Missoula Floods (15-18,000 ka) in the Pacific Northwest of the United States (Allen et ...

  Citation × Citation Citation Abstract Copy Title: Ancient Cataclysmic Floods in the Pacific Northwest: Ancestors to the Missoula Floods Author: Medley, Erica Year: 2012 Ancient Cataclysmic Floods were the Ice Age Floods that left erosional and depositional features and preceded the Missoula Floods (15-18,000 ka) in the Pacific Northwest of the United States (Allen et al., 2009). All previously studied ancient sites were visited (14) and new sites (11) were found; four Missoula Flood quarries were also visited; a total of 29 sites were studied in this thesis. The use of calcrete paleosols to provide relative age dates for flood deposits was analyzed in this thesis. Missoula Flood gravel pits were sampled in order to examine the degree of calcrete development in flood deposits of known ages. All of the Missoula Flood deposits tested contain Stage 1 calcrete soil development. Calcrete paleosols at sites with evidence for older floods were all analyzed. Eight sites have paleosols with Stage II development (3-12% CaCO3): Rulo Outcrop, Potholes Coulee, Leslie Road, Benge, E. Callaway Road, Collier Coulee, Palouse, and Connell. Five sites have paleosols with Stage II+ development (12-17% CaCO3): Brown Road, Leslie Road, Benge, Reese Coulee, and Connell. Fourteen sites have paleosols with Stage III development (17-35% CaCO3): The Dalles, Rulo Outcrop, Winans Road 1, Poplar Heights, Yakima Bluffs, Canal Outcrop, Othello Canal, Reese Coulee, Potholes Coulee, E. Callaway Road, Frenchmen Coulee, Macall, Ritzville, and East Connell. One site has a paleosol with Stage III+ development (35-50% CaCO3): Othello Canal. Ancient Cataclysmic flooding initiated in the Early Pleistocene, at least 1.5 Ma. Sixteen field sites show evidence for Early Pleistocene flooding, preserved in all six provinces: Othello Channels, Columbia River Gorge, Cheney-Palouse Scabland, Quincy Basin, Pasco Basin, and the Walla Walla Valley. There are 26 field sites with evidence for Middle Pleistocene flooding, present in all regions except Othello Channels. Eleven of those 26 sites also show evidence for Early Pleistocene floods. Evidence for Early and Middle Pleistocene floods is present over a wide distribution of elevations from 117 to 524 meters. Title: Ancient Cataclysmic Floods in the Pacific Northwest: Ancestors to the Missoula Floods Author: Medley, Erica Year: 2012 Ancient Cataclysmic Floods were the Ice Age Floods that left erosional and depositional features and preceded the Missoula Floods (15-18,000 ka) in the Pacific Northwest of the United States (Allen et al., 2009). All previously studied ancient sites were visited (14) and new sites (11) were found; four Missoula Flood quarries were also visited; a total of 29 sites were studied in this thesis. The use of calcrete paleosols to provide relative age dates for flood deposits was analyzed in this thesis. Missoula Flood gravel pits were sampled in order to examine the degree of calcrete development in flood deposits of known ages. All of the Missoula Flood deposits tested contain Stage 1 calcrete soil development. Calcrete paleosols at sites with evidence for older floods were all analyzed. Eight sites have paleosols with Stage II development (3-12% CaCO3): Rulo Outcrop, Potholes Coulee, Leslie Road, Benge, E. Callaway Road, Collier Coulee, Palouse, and Connell. Five sites have paleosols with Stage II+ development (12-17% CaCO3): Brown Road, Leslie Road, Benge, Reese Coulee, and Connell. Fourteen sites have paleosols with Stage III development (17-35% CaCO3): The Dalles, Rulo Outcrop, Winans Road 1, Poplar Heights, Yakima Bluffs, Canal Outcrop, Othello Canal, Reese Coulee, Potholes Coulee, E. Callaway Road, Frenchmen Coulee, Macall, Ritzville, and East Connell. One site has a paleosol with Stage III+ development (35-50% CaCO3): Othello Canal. Ancient Cataclysmic flooding initiated in the Early Pleistocene, at least 1.5 Ma. Sixteen field sites show evidence for Early Pleistocene flooding, preserved in all six provinces: Othello Channels, Columbia River Gorge, Cheney-Palouse Scabland, Quincy Basin, Pasco Basin, and the Walla Walla Valley. There are 26 field sites with evidence for Middle Pleistocene flooding, present in all regions except Othello Channels. Eleven of those 26 sites also show evidence for Early Pleistocene floods. Evidence for Early and Middle Pleistocene floods is present over a wide distribution of elevations from 117 to 524 meters. Close

• 3. [Article] Late-Holocene Flood History, Flood-Frequency, and Paleoclimate Analysis of the Central Black Hills, South Dakota

  Stratigraphic records in four basins in the central Black Hills in combination with hydraulic calculations show that all basins have experienced multiple large floods in the last 2,000 years with flow ...

  Citation × Citation Citation Abstract Copy Title: Late-Holocene Flood History, Flood-Frequency, and Paleoclimate Analysis of the Central Black Hills, South Dakota Author: Harden, Tessa M. Year: 2012 Stratigraphic records in four basins in the central Black Hills in combination with hydraulic calculations show that all basins have experienced multiple large floods in the last 2,000 years with flow rates substantially larger than those gaged historically. Flood-frequency analyses for the study reaches account for 29 paleofloods inferred from interpretation of stratigraphic records locally extending back 1,000 to almost 2,000 years. The addition of paleoflood data to the gaged and historical data significantly reduced uncertainties related to flood-frequency. For all study reaches the 95-percent confidence intervals about the low-probability quantile estimates (100-, 200-, and 500-year recurrence-intervals) were reduced by at least 78 percent relative to those for the gaged records only. In some cases, 95-percent uncertainty intervals were reduced by 99 percent or more. Additionally, a stratigraphic record of 35 large paleofloods and four large historical floods during the last 2,000 years (including several floods not used in the frequency analyses due to age constraints) reveal four flooding episodes at A.D.: 130-40, 640-670, 900-1290, and 1410 to present. During the Medieval Climate Anomaly (~A.D. 900-1300) the Black Hills experienced 13 large floods compared to nine large floods in the previous 800 years. This high concentration of large flooding events were likely caused by: 1) instability of air masses caused by stronger than normal westerlies; 2) larger or more frequent hurricanes in the Gulf of Mexico and Atlantic Ocean; and/or 3) reduced land covering vegetation and an increase in forest fires caused by the severe drought. By examining the response of streamflow to the MCA, it seems likely that if severe long-term drought conditions persist for the Black Hills region, an increase in the frequency and magnitude of large floods can be expected. The Black Hills paleofloods represent some of the largest known floods, relative to drainage area, for the United States. Many of the other largest known United States floods are in areas with physiographic and climatologic conditions broadly similar to the Black Hills--semi-arid and rugged landscapes that intercept and focus heavy precipitation from convective storm systems. Title: Late-Holocene Flood History, Flood-Frequency, and Paleoclimate Analysis of the Central Black Hills, South Dakota Author: Harden, Tessa M. Year: 2012 Stratigraphic records in four basins in the central Black Hills in combination with hydraulic calculations show that all basins have experienced multiple large floods in the last 2,000 years with flow rates substantially larger than those gaged historically. Flood-frequency analyses for the study reaches account for 29 paleofloods inferred from interpretation of stratigraphic records locally extending back 1,000 to almost 2,000 years. The addition of paleoflood data to the gaged and historical data significantly reduced uncertainties related to flood-frequency. For all study reaches the 95-percent confidence intervals about the low-probability quantile estimates (100-, 200-, and 500-year recurrence-intervals) were reduced by at least 78 percent relative to those for the gaged records only. In some cases, 95-percent uncertainty intervals were reduced by 99 percent or more. Additionally, a stratigraphic record of 35 large paleofloods and four large historical floods during the last 2,000 years (including several floods not used in the frequency analyses due to age constraints) reveal four flooding episodes at A.D.: 130-40, 640-670, 900-1290, and 1410 to present. During the Medieval Climate Anomaly (~A.D. 900-1300) the Black Hills experienced 13 large floods compared to nine large floods in the previous 800 years. This high concentration of large flooding events were likely caused by: 1) instability of air masses caused by stronger than normal westerlies; 2) larger or more frequent hurricanes in the Gulf of Mexico and Atlantic Ocean; and/or 3) reduced land covering vegetation and an increase in forest fires caused by the severe drought. By examining the response of streamflow to the MCA, it seems likely that if severe long-term drought conditions persist for the Black Hills region, an increase in the frequency and magnitude of large floods can be expected. The Black Hills paleofloods represent some of the largest known floods, relative to drainage area, for the United States. Many of the other largest known United States floods are in areas with physiographic and climatologic conditions broadly similar to the Black Hills--semi-arid and rugged landscapes that intercept and focus heavy precipitation from convective storm systems. Close

• 4. [Article] A Validated Tropical-Extratropical Flood Hazard Assessment for New York Harbor

  Recent studies of flood risk at New York Harbor (NYH) have shown disparate results for the 100 year storm tide, providing an uncertain foundation for the flood mitigation response after Hurricane Sandy. ...

  Citation × Citation Citation Abstract Copy Title: A Validated Tropical-Extratropical Flood Hazard Assessment for New York Harbor Author: Orton, Philip M., Hall, T. M., Talke, Stefan A., Blumberg, Alan F., Georgas, Nickitas, Vinogradov, S. Year: 2016 Recent studies of flood risk at New York Harbor (NYH) have shown disparate results for the 100 year storm tide, providing an uncertain foundation for the flood mitigation response after Hurricane Sandy. Here we present a flood hazard assessment that improves confidence in our understanding of the region's present-day potential for flooding, by separately including the contribution of tropical cyclones (TCs) and extratropical cyclones (ETCs), and validating our modeling study at multiple stages against historical observations. The TC assessment is based on a climatology of 606 synthetic storms developed from a statistical-stochastic model of North Atlantic TCs. The ETC assessment is based on simulations of historical storms with many random tide scenarios. Synthetic TC landfall rates and the final TC and ETC flood exceedance curves are all shown to be consistent with curves computed using historical data, within 95% confidence ranges. Combining the ETC and TC results together, the 100 year return period storm tide at NYH is 2.70 m (2.51–2.92 at 95% confidence), and Hurricane Sandy's storm tide of 3.38 m was a 260 year (170–420) storm tide. Deeper analyses of historical flood reports from estimated Category-3 hurricanes in 1788 and 1821 lead to new estimates and reduced uncertainties for their floods and show that Sandy's storm tide was the largest at NYH back to at least 1700. The flood exceedance curves for ETCs and TCs have sharply different slopes due to their differing meteorology and frequency, warranting separate treatment in hazard assessments. Title: A Validated Tropical-Extratropical Flood Hazard Assessment for New York Harbor Author: Orton, Philip M., Hall, T. M., Talke, Stefan A., Blumberg, Alan F., Georgas, Nickitas, Vinogradov, S. Year: 2016 Recent studies of flood risk at New York Harbor (NYH) have shown disparate results for the 100 year storm tide, providing an uncertain foundation for the flood mitigation response after Hurricane Sandy. Here we present a flood hazard assessment that improves confidence in our understanding of the region's present-day potential for flooding, by separately including the contribution of tropical cyclones (TCs) and extratropical cyclones (ETCs), and validating our modeling study at multiple stages against historical observations. The TC assessment is based on a climatology of 606 synthetic storms developed from a statistical-stochastic model of North Atlantic TCs. The ETC assessment is based on simulations of historical storms with many random tide scenarios. Synthetic TC landfall rates and the final TC and ETC flood exceedance curves are all shown to be consistent with curves computed using historical data, within 95% confidence ranges. Combining the ETC and TC results together, the 100 year return period storm tide at NYH is 2.70 m (2.51–2.92 at 95% confidence), and Hurricane Sandy's storm tide of 3.38 m was a 260 year (170–420) storm tide. Deeper analyses of historical flood reports from estimated Category-3 hurricanes in 1788 and 1821 lead to new estimates and reduced uncertainties for their floods and show that Sandy's storm tide was the largest at NYH back to at least 1700. The flood exceedance curves for ETCs and TCs have sharply different slopes due to their differing meteorology and frequency, warranting separate treatment in hazard assessments. Close

• 5. [Article] State space approach to flood stage estimation

  A flood routing and stage prediction model is developed using the techniques of State Space and Kalman filtering. The governing equation is the physically based hydrologic method of flood routing with ...

  Citation × Citation Citation Abstract Copy Title: State space approach to flood stage estimation Author: Jones, Gregory Allen Year: 1984 A flood routing and stage prediction model is developed using the techniques of State Space and Kalman filtering. The governing equation is the physically based hydrologic method of flood routing with the output being an optimal estimate of stage given known inputs of streamflow. These equations are developed in state space and the Kalman filter is employed to estimate the flow and river stage. The model is applied to the Toutle and Cowlitz Rivers in the State of Washington, where the stage is affected by a shifting bed elevation. With the deterministic inputs at Mayfield Dam on the Cowlitz and Tower Road on the Toutle, the optimal output of stage is predicted at Castle Rock on the Cowlitz River. Addition of the Kalman Filter improves stage prediction based on an application to an observed storm event. Title: State space approach to flood stage estimation Author: Jones, Gregory Allen Year: 1984 A flood routing and stage prediction model is developed using the techniques of State Space and Kalman filtering. The governing equation is the physically based hydrologic method of flood routing with the output being an optimal estimate of stage given known inputs of streamflow. These equations are developed in state space and the Kalman filter is employed to estimate the flow and river stage. The model is applied to the Toutle and Cowlitz Rivers in the State of Washington, where the stage is affected by a shifting bed elevation. With the deterministic inputs at Mayfield Dam on the Cowlitz and Tower Road on the Toutle, the optimal output of stage is predicted at Castle Rock on the Cowlitz River. Addition of the Kalman Filter improves stage prediction based on an application to an observed storm event. Close

• 6. [Article] The Influence of Floodplain Restoration on Flow and Sediment Dynamics in an Urban River

  A study of floodplain sedimentation on a recently restored floodplain is presented. This study uses a two-dimensional hydro-morphodynamic model for predicting flow and suspended-sediment dynamics in the ...

  Citation × Citation Citation Abstract Copy Title: The Influence of Floodplain Restoration on Flow and Sediment Dynamics in an Urban River Author: Ahilan, Sangaralingam, Guan, Mingfu, Sleigh, Andrew, Wright, Nigel G., Chang, Heejun Year: 2016 A study of floodplain sedimentation on a recently restored floodplain is presented. This study uses a two-dimensional hydro-morphodynamic model for predicting flow and suspended-sediment dynamics in the downstream of Johnson Creek, the East Lents reach, where the bank of the river has been reconfigured to reconnect to a restored floodplain on a 0.26 km2 (26-ha) site. The simulation scenarios include 10-, 50-, 100- and 500-year event-based deposition modelling of flood events and long-term modelling using the 64 historical flood events between 1941 and 2014. Simulation results showed that the restored floodplain significantly attenuates the upstream flood peak by up to 25% at the downstream. Results also indicated that approximately 20%–30% of sediment from the upstream is deposited on the East Lents floodplain. Furthermore, deposited sediment over the simulated period (1941–2014) is approximately 0.1% of the basin's flood storage capacity; however, the reduction in the storage does not offset the overall flood resilience impact of the flood basin. The sediment conservation at the East Lents flood basin as predicted by the model reduces the annual sediment loading of the Johnson Creek by 1% at the confluence with Willamette River, providing both improved water quality and flood resilience further downstream. Title: The Influence of Floodplain Restoration on Flow and Sediment Dynamics in an Urban River Author: Ahilan, Sangaralingam, Guan, Mingfu, Sleigh, Andrew, Wright, Nigel G., Chang, Heejun Year: 2016 A study of floodplain sedimentation on a recently restored floodplain is presented. This study uses a two-dimensional hydro-morphodynamic model for predicting flow and suspended-sediment dynamics in the downstream of Johnson Creek, the East Lents reach, where the bank of the river has been reconfigured to reconnect to a restored floodplain on a 0.26 km2 (26-ha) site. The simulation scenarios include 10-, 50-, 100- and 500-year event-based deposition modelling of flood events and long-term modelling using the 64 historical flood events between 1941 and 2014. Simulation results showed that the restored floodplain significantly attenuates the upstream flood peak by up to 25% at the downstream. Results also indicated that approximately 20%–30% of sediment from the upstream is deposited on the East Lents floodplain. Furthermore, deposited sediment over the simulated period (1941–2014) is approximately 0.1% of the basin's flood storage capacity; however, the reduction in the storage does not offset the overall flood resilience impact of the flood basin. The sediment conservation at the East Lents flood basin as predicted by the model reduces the annual sediment loading of the Johnson Creek by 1% at the confluence with Willamette River, providing both improved water quality and flood resilience further downstream. Close

• 7. [Article] Potential Impacts of Climate Change on Flood-Induced Travel Disruptions: A Case Study of Portland, Oregon, USA

  This study investigated potential impacts of climate change on travel disruption resulting from road closures in two urban watersheds in the Portland, Oregon, metropolitan area. We used ensemble climate ...

  Citation × Citation Citation Abstract Copy Title: Potential Impacts of Climate Change on Flood-Induced Travel Disruptions: A Case Study of Portland, Oregon, USA Author: Chang, Heejun, Lafrenz, Martin, Jung, Il-won, Figliozzi, Miguel, Platman, Deena, Pederson, Cindy Year: 2010 This study investigated potential impacts of climate change on travel disruption resulting from road closures in two urban watersheds in the Portland, Oregon, metropolitan area. We used ensemble climate change scenarios, a hydrologic model, a stream channel survey, a hydraulic model, and a travel forecast model to develop an integrated impact assessment method. High-resolution climate change scenarios are based on the combinations of two emission scenarios and eight general circulation models. The Precipitation-Runoff Modeling System was calibrated and validated for the historical period of 1988 and 2006 and simulated for determining the probability of floods for 2020 through 2049. We surveyed stream cross-sections at five road crossings for stream channel geometry and determined flood water surface elevations using the Hydrologic Engineering Centers River Analysis System (HEC-RAS) model. Four of the surveyed bridges and roadways were lower in elevation than the current 100-year flood water surface elevation, leading to relatively frequent nuisance flooding. These roadway flooding events will become more frequent under some climate change scenarios in the future, but climate change impacts will depend on local geomorphic conditions. Whereas vehicle miles traveled was not significantly affected by road closure, vehicle hours delay demonstrated a greater impact from road closures, increasing by 10 percent in the Fanno Creek area. Our research demonstrated the usefulness of the integration of top-down and bottom-up approaches in climate change impact assessment and the need for spatially explicit modeling and participatory planning in flood management and transportation planning under increasing climate uncertainty. Title: Potential Impacts of Climate Change on Flood-Induced Travel Disruptions: A Case Study of Portland, Oregon, USA Author: Chang, Heejun, Lafrenz, Martin, Jung, Il-won, Figliozzi, Miguel, Platman, Deena, Pederson, Cindy Year: 2010 This study investigated potential impacts of climate change on travel disruption resulting from road closures in two urban watersheds in the Portland, Oregon, metropolitan area. We used ensemble climate change scenarios, a hydrologic model, a stream channel survey, a hydraulic model, and a travel forecast model to develop an integrated impact assessment method. High-resolution climate change scenarios are based on the combinations of two emission scenarios and eight general circulation models. The Precipitation-Runoff Modeling System was calibrated and validated for the historical period of 1988 and 2006 and simulated for determining the probability of floods for 2020 through 2049. We surveyed stream cross-sections at five road crossings for stream channel geometry and determined flood water surface elevations using the Hydrologic Engineering Centers River Analysis System (HEC-RAS) model. Four of the surveyed bridges and roadways were lower in elevation than the current 100-year flood water surface elevation, leading to relatively frequent nuisance flooding. These roadway flooding events will become more frequent under some climate change scenarios in the future, but climate change impacts will depend on local geomorphic conditions. Whereas vehicle miles traveled was not significantly affected by road closure, vehicle hours delay demonstrated a greater impact from road closures, increasing by 10 percent in the Fanno Creek area. Our research demonstrated the usefulness of the integration of top-down and bottom-up approaches in climate change impact assessment and the need for spatially explicit modeling and participatory planning in flood management and transportation planning under increasing climate uncertainty. Close

• 8. [Article] Modeling of Historic Columbia River Flood Impacts Based on Delft 3D Simulations

  Natural and anthropogenic processes over the past 150 years have altered the bathymetry of the Lower Columbia River (LCR) and have changed the long wave propagation of tides and floods. Possible causes ...

  Citation × Citation Citation Abstract Copy Title: Modeling of Historic Columbia River Flood Impacts Based on Delft 3D Simulations Author: Helaire, Lumas Terence Year: 2016 Natural and anthropogenic processes over the past 150 years have altered the bathymetry of the Lower Columbia River (LCR) and have changed the long wave propagation of tides and floods. Possible causes for the increase in tidal amplitudes (+7% in tidal range in Astoria) are decreases in river discharge, lengthening of the river channel due to the construction of jetties at the mouth, dredging and deepening of the shipping channel, and reduction of the tidal prism due to the filling and diking of tidal wetlands. In this study, changes in the characteristics of long waves are elucidated by developing two hydrodynamic models of the LCR which reflect historical and modern bathymetric conditions and forcing. The historic model simulates late 19th century conditions and is extensively validated using recently recovered tide records along the LCR (e.g., Astoria, 1853-1876) and river stage measurements (e.g., Portland, 1876-1964). Results suggest that water levels in Portland at low river discharge are up to 0.5-1.0m lower than in the past. However, historical water levels during a flood scenario based on the 1880 spring freshet are similar to modern water levels. Since tidal range in the modern scenario is persistently higher at all locations, the flood risk in many locations along the LCR has increased for the same boundary conditions. The results are explained by considering the governing equations of momentum and mass-conservation. At low river flow, greater depth leads to reduced frictional effects, producing amplified tidal range and tidal velocities but a decreased river slope (and lower Portland water levels). At high flow, the modern flood is confined by dikes and the loss of wetlands, which counteracts the effect of decreased friction. Nonetheless, the high friction of the historical wooded floodplain also confined the historical flood path. Hence, historical and modern flood heights are surprisingly similar, though scaling analysis suggests that the historical flood wave was more diffusive. Title: Modeling of Historic Columbia River Flood Impacts Based on Delft 3D Simulations Author: Helaire, Lumas Terence Year: 2016 Natural and anthropogenic processes over the past 150 years have altered the bathymetry of the Lower Columbia River (LCR) and have changed the long wave propagation of tides and floods. Possible causes for the increase in tidal amplitudes (+7% in tidal range in Astoria) are decreases in river discharge, lengthening of the river channel due to the construction of jetties at the mouth, dredging and deepening of the shipping channel, and reduction of the tidal prism due to the filling and diking of tidal wetlands. In this study, changes in the characteristics of long waves are elucidated by developing two hydrodynamic models of the LCR which reflect historical and modern bathymetric conditions and forcing. The historic model simulates late 19th century conditions and is extensively validated using recently recovered tide records along the LCR (e.g., Astoria, 1853-1876) and river stage measurements (e.g., Portland, 1876-1964). Results suggest that water levels in Portland at low river discharge are up to 0.5-1.0m lower than in the past. However, historical water levels during a flood scenario based on the 1880 spring freshet are similar to modern water levels. Since tidal range in the modern scenario is persistently higher at all locations, the flood risk in many locations along the LCR has increased for the same boundary conditions. The results are explained by considering the governing equations of momentum and mass-conservation. At low river flow, greater depth leads to reduced frictional effects, producing amplified tidal range and tidal velocities but a decreased river slope (and lower Portland water levels). At high flow, the modern flood is confined by dikes and the loss of wetlands, which counteracts the effect of decreased friction. Nonetheless, the high friction of the historical wooded floodplain also confined the historical flood path. Hence, historical and modern flood heights are surprisingly similar, though scaling analysis suggests that the historical flood wave was more diffusive. Close

• 9. [Article] Hydrodynamic and Water Quality Modeling of the Chehalis River in Washington

  The Chehalis River Basin is located in the southwest region of Washington and is over 125 miles long flowing through agricultural, residential, industrial, and forest land. Four major rivers, many smaller ...

  Citation × Citation Citation Abstract Copy Title: Hydrodynamic and Water Quality Modeling of the Chehalis River in Washington Author: Van Glubt, Sarah, Wells, Scott A., Berger, Chris J. Year: 2017 The Chehalis River Basin is located in the southwest region of Washington and is over 125 miles long flowing through agricultural, residential, industrial, and forest land. Four major rivers, many smaller creeks, five wastewater treatment plants, and groundwater discharge to the Chehalis River. Flooding is a major problem in the relatively flat areas surrounding the cities of Chehalis and Centralia. As a result, construction of a flood-control dam in the upper basin has been proposed. One major concern of constructing a dam is the potentially severe impacts to fish health and habitat. The Chehalis River has routinely violated water quality standards for primarily temperature and dissolved oxygen. CE-QUAL-W2, a two-dimensional (longitudinal and vertical) hydrodynamic and water quality model, was used to simulate the Chehalis River, including free flowing river stretches and stratified (in summer) lake-like stretches. The goals of this research were to assess the flood retention structure’s impacts to water quality, as well as river responses to potential climate change scenarios. In order to use the model to achieve these goals, calibration to field data for flow, temperature, and water quality constituents was performed for the years 2013 and 2014. Once calibration was complete, model scenarios for future climate conditions and dam operating regimes were conducted. Future conditions showed predictions of warmer water temperatures and slight changes to water quality conditions on the river. As fish in the area prefer cooler water temperatures, this could pose a threat to fish health and habitat. Flood retention structures with the purpose of flood retention only (only operating during times of flooding) gave model predictions for daily maximum temperature higher than structures that employed flood retention and flow augmentation (operating during all times of the year). This suggested the management of flow passage or retention by the dam is important for water quality on the river. Title: Hydrodynamic and Water Quality Modeling of the Chehalis River in Washington Author: Van Glubt, Sarah, Wells, Scott A., Berger, Chris J. Year: 2017 The Chehalis River Basin is located in the southwest region of Washington and is over 125 miles long flowing through agricultural, residential, industrial, and forest land. Four major rivers, many smaller creeks, five wastewater treatment plants, and groundwater discharge to the Chehalis River. Flooding is a major problem in the relatively flat areas surrounding the cities of Chehalis and Centralia. As a result, construction of a flood-control dam in the upper basin has been proposed. One major concern of constructing a dam is the potentially severe impacts to fish health and habitat. The Chehalis River has routinely violated water quality standards for primarily temperature and dissolved oxygen. CE-QUAL-W2, a two-dimensional (longitudinal and vertical) hydrodynamic and water quality model, was used to simulate the Chehalis River, including free flowing river stretches and stratified (in summer) lake-like stretches. The goals of this research were to assess the flood retention structure’s impacts to water quality, as well as river responses to potential climate change scenarios. In order to use the model to achieve these goals, calibration to field data for flow, temperature, and water quality constituents was performed for the years 2013 and 2014. Once calibration was complete, model scenarios for future climate conditions and dam operating regimes were conducted. Future conditions showed predictions of warmer water temperatures and slight changes to water quality conditions on the river. As fish in the area prefer cooler water temperatures, this could pose a threat to fish health and habitat. Flood retention structures with the purpose of flood retention only (only operating during times of flooding) gave model predictions for daily maximum temperature higher than structures that employed flood retention and flow augmentation (operating during all times of the year). This suggested the management of flow passage or retention by the dam is important for water quality on the river. Close

• 10. [Article] A Regional Bayesian Hierarchical Model for Flood Frequency Analysis

  In this study, we propose a regional Bayesian hierarchical model for flood frequency analysis. The Bayesian method is an alternative to the traditional regional flood frequency analysis. Instead of relying ...

  Citation × Citation Citation Abstract Copy Title: A Regional Bayesian Hierarchical Model for Flood Frequency Analysis Author: Yan, Hongxiang, Moradkhani, Hamid Year: 2015 In this study, we propose a regional Bayesian hierarchical model for flood frequency analysis. The Bayesian method is an alternative to the traditional regional flood frequency analysis. Instead of relying on the delineation of implicit homogeneous regions, the Bayesian hierarchical method describes the spatial dependence in its inner structure. Similar to the classical Bayesian hierarchical model, the process layer of our model presents the spatial variability of the parameters by considering different covariates (e.g., drainage area, elevation, precipitation). Beyond the three classical layers (data, process, and prior) of the Bayesian hierarchical model, we add a new layer referred to as the “L-moments layer”. The L-moments layer uses L-moments theory to select the best-fit probability distribution based on the available data. This new layer can overcome the subjective selection of the distribution based on extreme value theory and determine the distribution from the data instead. By adding this layer, we can combine the merits of regional flood frequency and Bayesian methods. A standard process of covariates selection is also proposed in the Bayesian hierarchical model. The performance of the Bayesian model is assessed by a case study over the Willamette River Basin in the Pacific Northwest, U.S. The uncertainty of different flood percentiles can be quantified from the posterior distributions using the Markov Chain Monte Carlo method. Temporal changes for the 100-year flood percentiles are also examined using a 20- and 30-year moving window method. The calculated shifts in flood risk can aid future water resources planning and management. Title: A Regional Bayesian Hierarchical Model for Flood Frequency Analysis Author: Yan, Hongxiang, Moradkhani, Hamid Year: 2015 In this study, we propose a regional Bayesian hierarchical model for flood frequency analysis. The Bayesian method is an alternative to the traditional regional flood frequency analysis. Instead of relying on the delineation of implicit homogeneous regions, the Bayesian hierarchical method describes the spatial dependence in its inner structure. Similar to the classical Bayesian hierarchical model, the process layer of our model presents the spatial variability of the parameters by considering different covariates (e.g., drainage area, elevation, precipitation). Beyond the three classical layers (data, process, and prior) of the Bayesian hierarchical model, we add a new layer referred to as the “L-moments layer”. The L-moments layer uses L-moments theory to select the best-fit probability distribution based on the available data. This new layer can overcome the subjective selection of the distribution based on extreme value theory and determine the distribution from the data instead. By adding this layer, we can combine the merits of regional flood frequency and Bayesian methods. A standard process of covariates selection is also proposed in the Bayesian hierarchical model. The performance of the Bayesian model is assessed by a case study over the Willamette River Basin in the Pacific Northwest, U.S. The uncertainty of different flood percentiles can be quantified from the posterior distributions using the Markov Chain Monte Carlo method. Temporal changes for the 100-year flood percentiles are also examined using a 20- and 30-year moving window method. The calculated shifts in flood risk can aid future water resources planning and management. Close

• 11. [Article] Quantifying Uncertainty in Urban Flooding Analysis Considering Hydro-Climatic Projection and Urban Development Effects

  How will the combined impacts of land use change, climate change, and hydrologic modeling influence changes in urban flood frequency and what is the main uncertainty source of the results? Will such changes ...

  Citation × Citation Citation Abstract Copy Title: Quantifying Uncertainty in Urban Flooding Analysis Considering Hydro-Climatic Projection and Urban Development Effects Author: Jung, Il-Won, Chang, Heejun, Moradkhani, Hamid Year: 2011 How will the combined impacts of land use change, climate change, and hydrologic modeling influence changes in urban flood frequency and what is the main uncertainty source of the results? Will such changes differ by catchment with different degrees of current and future urban development? We attempt to answer these questions in two catchments with different degrees of urbanization, the Fanno catchment with 84% urban land use and the Johnson catchment with 36% urban land use, both located in the Pacific Northwest of the US. Five uncertainty sources – general circulation model (GCM) structures, future greenhouse gas (GHG) emission scenarios, land use change scenarios, natural variability, and hydrologic model parameters – are considered to compare the relative source of uncertainty in flood frequency projections. Two land use change scenarios, conservation and development, representing possible future land use changes are used for analysis. Results show the highest increase in flood frequency under the combination of medium high GHG emission (A1B) and development scenarios, and the lowest increase under the combination of low GHG emission (B1) and conservation scenarios. Although the combined impact is more significant to flood frequency change than individual scenarios, it does not linearly Title: Quantifying Uncertainty in Urban Flooding Analysis Considering Hydro-Climatic Projection and Urban Development Effects Author: Jung, Il-Won, Chang, Heejun, Moradkhani, Hamid Year: 2011 How will the combined impacts of land use change, climate change, and hydrologic modeling influence changes in urban flood frequency and what is the main uncertainty source of the results? Will such changes differ by catchment with different degrees of current and future urban development? We attempt to answer these questions in two catchments with different degrees of urbanization, the Fanno catchment with 84% urban land use and the Johnson catchment with 36% urban land use, both located in the Pacific Northwest of the US. Five uncertainty sources – general circulation model (GCM) structures, future greenhouse gas (GHG) emission scenarios, land use change scenarios, natural variability, and hydrologic model parameters – are considered to compare the relative source of uncertainty in flood frequency projections. Two land use change scenarios, conservation and development, representing possible future land use changes are used for analysis. Results show the highest increase in flood frequency under the combination of medium high GHG emission (A1B) and development scenarios, and the lowest increase under the combination of low GHG emission (B1) and conservation scenarios. Although the combined impact is more significant to flood frequency change than individual scenarios, it does not linearly Close

• 12. [Article] Channel Shallowing as Mitigation of Coastal Flooding

  Here, we demonstrate that reductions in the depth of inlets or estuary channels can be used to reduce or prevent coastal flooding. A validated hydrodynamic model of Jamaica Bay, New York City (NYC), is ...

  Citation × Citation Citation Abstract Copy Title: Channel Shallowing as Mitigation of Coastal Flooding Author: Orton, Philip M., Talke, Stefan A., Jay, David A., Yin, Larry, Blumberg, Alan F., Georgas, Nickitas, Zhao, Haihong, Roberts, Hugh J., MacManus, Kytt Year: 2015 Here, we demonstrate that reductions in the depth of inlets or estuary channels can be used to reduce or prevent coastal flooding. A validated hydrodynamic model of Jamaica Bay, New York City (NYC), is used to test nature-based adaptation measures in ameliorating flooding for NYC’s two largest historical coastal flood events. In addition to control runs with modern bathymetry, three altered landscape scenarios are tested: (1) increasing the area of wetlands to their 1879 footprint and bathymetry, but leaving deep shipping channels unaltered; (2) shallowing all areas deeper than 2 m in the bay to be 2 m below Mean Low Water; (3) shallowing only the narrowest part of the inlet to the bay. These three scenarios are deliberately extreme and designed to evaluate the leverage each approach exerts on water levels. They result in peak water level reductions of 0.3%, 15%, and 6.8% for Hurricane Sandy, and 2.4%, 46% and 30% for the Category-3 hurricane of 1821, respectively (bay-wide averages). These results suggest that shallowing can provide greater flood protection than wetland restoration, and it is particularly effective at reducing "fast-pulse" storm surges that rise and fall quickly over several hours, like that of the 1821 storm. Nonetheless, the goal of flood mitigation must be weighed against economic, navigation, and ecological needs, and practical concerns such as the availability of sediment. Title: Channel Shallowing as Mitigation of Coastal Flooding Author: Orton, Philip M., Talke, Stefan A., Jay, David A., Yin, Larry, Blumberg, Alan F., Georgas, Nickitas, Zhao, Haihong, Roberts, Hugh J., MacManus, Kytt Year: 2015 Here, we demonstrate that reductions in the depth of inlets or estuary channels can be used to reduce or prevent coastal flooding. A validated hydrodynamic model of Jamaica Bay, New York City (NYC), is used to test nature-based adaptation measures in ameliorating flooding for NYC’s two largest historical coastal flood events. In addition to control runs with modern bathymetry, three altered landscape scenarios are tested: (1) increasing the area of wetlands to their 1879 footprint and bathymetry, but leaving deep shipping channels unaltered; (2) shallowing all areas deeper than 2 m in the bay to be 2 m below Mean Low Water; (3) shallowing only the narrowest part of the inlet to the bay. These three scenarios are deliberately extreme and designed to evaluate the leverage each approach exerts on water levels. They result in peak water level reductions of 0.3%, 15%, and 6.8% for Hurricane Sandy, and 2.4%, 46% and 30% for the Category-3 hurricane of 1821, respectively (bay-wide averages). These results suggest that shallowing can provide greater flood protection than wetland restoration, and it is particularly effective at reducing "fast-pulse" storm surges that rise and fall quickly over several hours, like that of the 1821 storm. Nonetheless, the goal of flood mitigation must be weighed against economic, navigation, and ecological needs, and practical concerns such as the availability of sediment. Close

• 13. [Article] It’s an Emergency: The Portland State University Library Flood

  Preservation Librarian Kris Kern discusses flooding at the Portland State University Library and lessons learned to prevent extended damage to the Library collections.

  Citation × Citation Citation Abstract Copy Title: It’s an Emergency: The Portland State University Library Flood Author: Kern, Kristen Year: 2008 Preservation Librarian Kris Kern discusses flooding at the Portland State University Library and lessons learned to prevent extended damage to the Library collections. Title: It’s an Emergency: The Portland State University Library Flood Author: Kern, Kristen Year: 2008 Preservation Librarian Kris Kern discusses flooding at the Portland State University Library and lessons learned to prevent extended damage to the Library collections. Close

• 14. [Article] First season effects of managed flooding on the invasive species Phalaris arundinacea L. and shoreline vegetation communities in an urban wetland

  Recent management efforts in the Smith and Bybee Lakes Wildlife Area (SBL), a 700-ha preserve in north Portland, Oregon, have included using a water control structure to suppress invasive reed canarygrass ...

  Citation × Citation Citation Abstract Copy Title: First season effects of managed flooding on the invasive species Phalaris arundinacea L. and shoreline vegetation communities in an urban wetland Author: Jenkins, Noah John Year: 2005 Recent management efforts in the Smith and Bybee Lakes Wildlife Area (SBL), a 700-ha preserve in north Portland, Oregon, have included using a water control structure to suppress invasive reed canarygrass (Phalaris arundinacea L.) by flooding during spring and early summer growth periods. For the first year of managed flooding, I sought to determine: (a) the extent and distribution of reed canarygrass at SBL; (b) the effectiveness of the change in water level at suppressing reed canarygrass; and ( c) the effects of the change in water level on other plant species. I established 30 vegetation transects throughout SBL before completion of the water control structure. These transects were randomly distributed, placed perpendicularly to the shorelines of the wetlands, and had a cumulative length of 3.1 km. I measured vegetation on the transects in autumn 2003 and autumn 2004 using the line intercept method at 10-cm intervals. I surveyed the transects to generate elevation profiles, accurate to 0.15 cm, to determine depth and duration of flooding, which I correlated with vegetative changes. I also monitored inundation depth, growth, and phenological response of individual stands of reed canarygrass during the 2004 growing season. Title: First season effects of managed flooding on the invasive species Phalaris arundinacea L. and shoreline vegetation communities in an urban wetland Author: Jenkins, Noah John Year: 2005 Recent management efforts in the Smith and Bybee Lakes Wildlife Area (SBL), a 700-ha preserve in north Portland, Oregon, have included using a water control structure to suppress invasive reed canarygrass (Phalaris arundinacea L.) by flooding during spring and early summer growth periods. For the first year of managed flooding, I sought to determine: (a) the extent and distribution of reed canarygrass at SBL; (b) the effectiveness of the change in water level at suppressing reed canarygrass; and ( c) the effects of the change in water level on other plant species. I established 30 vegetation transects throughout SBL before completion of the water control structure. These transects were randomly distributed, placed perpendicularly to the shorelines of the wetlands, and had a cumulative length of 3.1 km. I measured vegetation on the transects in autumn 2003 and autumn 2004 using the line intercept method at 10-cm intervals. I surveyed the transects to generate elevation profiles, accurate to 0.15 cm, to determine depth and duration of flooding, which I correlated with vegetative changes. I also monitored inundation depth, growth, and phenological response of individual stands of reed canarygrass during the 2004 growing season. Close

• 15. [Article] Future Flooding Impacts on Transportation Infrastructure and Traffic Patterns Resulting from Climate Change

  This study investigated potential impacts of climate change on travel disruption resulting from road closures in two urban watersheds in the Portland metropolitan area. We used ensemble climate change ...

  Citation × Citation Citation Abstract Copy Title: Future Flooding Impacts on Transportation Infrastructure and Traffic Patterns Resulting from Climate Change Author: Chang, Heejun, Lafrenz, Martin, Jung, Il-Won, Figliozzi, Miguel A., Melgoza, Rolando, Ruelas, David, Platman, Deena, Pederson, Cindy Year: 2011 This study investigated potential impacts of climate change on travel disruption resulting from road closures in two urban watersheds in the Portland metropolitan area. We used ensemble climate change scenarios, a hydrologic model, stream channel survey, a hydraulic model, and a travel forecast model to develop an integrated impact assessment method. High-resolution climate change scenarios are based on the combinations of two emission scenarios and eight general circulation models. The Precipitation-Runoff Modeling System was calibrated and validated for the period 1988-2006, and simulated for determining the probability of floods from 2020-2049. We surveyed stream cross sections at five road crossings for stream channel geometry and determined floodwater surface elevations using the HEC-RAS model. Four of the surveyed bridges and roadways were lower in elevation than the current 100-year floodwater surface elevation, leading to relatively frequent nuisance flooding. These roadway flooding events will become more frequent under some climate change scenarios in the future, but climate change impacts will depend on local geomorphic conditions. While vehicle miles traveled were not significantly affected by road closure, vehicle-hours delay demonstrated a greater impact from road closures, increasing by 10 percent in the Fanno Creek area. Results indicate that any cost analysis is extremely sensitive to the occurrence of human fatalities or injuries and fairly insensitive to delay costs. In addition, this research presents a comprehensive classification of flooding costs, identifies preventative measures, and makes short- and long-term recommendations. Our research demonstrated the usefulness of the integration of top-down and bottom-up approaches in climate change impact assessment, and the need for spatially explicit modeling and participatory planning in flood management and transportation planning under increasing climate uncertainty. Title: Future Flooding Impacts on Transportation Infrastructure and Traffic Patterns Resulting from Climate Change Author: Chang, Heejun, Lafrenz, Martin, Jung, Il-Won, Figliozzi, Miguel A., Melgoza, Rolando, Ruelas, David, Platman, Deena, Pederson, Cindy Year: 2011 This study investigated potential impacts of climate change on travel disruption resulting from road closures in two urban watersheds in the Portland metropolitan area. We used ensemble climate change scenarios, a hydrologic model, stream channel survey, a hydraulic model, and a travel forecast model to develop an integrated impact assessment method. High-resolution climate change scenarios are based on the combinations of two emission scenarios and eight general circulation models. The Precipitation-Runoff Modeling System was calibrated and validated for the period 1988-2006, and simulated for determining the probability of floods from 2020-2049. We surveyed stream cross sections at five road crossings for stream channel geometry and determined floodwater surface elevations using the HEC-RAS model. Four of the surveyed bridges and roadways were lower in elevation than the current 100-year floodwater surface elevation, leading to relatively frequent nuisance flooding. These roadway flooding events will become more frequent under some climate change scenarios in the future, but climate change impacts will depend on local geomorphic conditions. While vehicle miles traveled were not significantly affected by road closure, vehicle-hours delay demonstrated a greater impact from road closures, increasing by 10 percent in the Fanno Creek area. Results indicate that any cost analysis is extremely sensitive to the occurrence of human fatalities or injuries and fairly insensitive to delay costs. In addition, this research presents a comprehensive classification of flooding costs, identifies preventative measures, and makes short- and long-term recommendations. Our research demonstrated the usefulness of the integration of top-down and bottom-up approaches in climate change impact assessment, and the need for spatially explicit modeling and participatory planning in flood management and transportation planning under increasing climate uncertainty. Close

• 16. [Article] Hydrodynamic and Water Quality Modeling of the Chehalis River Using CE-QUAL-W2

  The Chehalis River Basin is located in the southwest region of Washington State, originating in the Olympic Mountains and flowing to Grays Harbor and the Pacific Ocean. The Chehalis River is over 125 miles, ...

  Citation × Citation Citation Abstract Copy Title: Hydrodynamic and Water Quality Modeling of the Chehalis River Using CE-QUAL-W2 Author: Van Glubt, Sarah Year: 2017 The Chehalis River Basin is located in the southwest region of Washington State, originating in the Olympic Mountains and flowing to Grays Harbor and the Pacific Ocean. The Chehalis River is over 125 miles, exists within five counties, and flows through agricultural, residential, industrial, and forest land areas. Four major rivers discharge to the Chehalis River, as well as many smaller creeks, five wastewater treatment plants, and groundwater flows. Flooding is a major problem in the relatively flat areas surrounding the cities of Chehalis and Centralia, with severe consequences for property, safety and transportation. As a result, construction of a flood-control dam in the upper basin has been proposed. One major concern of constructing a dam is the potentially severe impacts to fish health and habitat. The Chehalis River has routinely violated water quality standards for primarily temperature and dissolved oxygen, and has had multiple water quality and Total Maximum Daily Load studies beginning in 1990. CE-QUAL-W2, a two-dimensional (longitudinal and vertical) hydrodynamic and water quality model, was used to simulate the Chehalis River, including free flowing river stretches and stratified (in summer) lake-like stretches. The goals of this research were to assess the flood retention structure's impacts to water quality, as well as river responses to potential climate change scenarios. In order to use the model to achieve these goals, calibration to field data for flow, temperature, and water quality constituents was performed. This involved developing meteorological data, riparian shading data, and flow, temperature, water quality records for all tributaries during the calibration period of January 1, 2013 to December 31, 2014. System cross-sectional geometry data were also required for the model grid. Because of the short travel time in the river, the model was sensitive to boundary condition data, wind speed, bathymetry, nutrient kinetics, and algae, epiphyton, and zooplankton kinetics. Future conditions showed predictions of warmer water temperatures and slight changes to water quality conditions on the river. As fish in the area prefer cooler water temperatures, this could pose a threat to fish health and habitat. Flood retention structures also showed impacts to river temperature and water quality. Structures with the purpose of flood retention only (only operating during times of flooding) gave model predictions for daily maximum temperature higher than structures that employed flood retention and flow augmentation (operating during all times of the year). This suggested the management of flow passage or retention by the dam is important for water quality on the river. As this research continues improvements will be made, particularly to temperature and water quality constituents. Additional data for the system would be beneficial to this process. Model predictions of temperature were sensitive to meteorological data, including cloud cover, which were largely estimated based on solar radiation. Additional meteorological data throughout the basin would be useful to temperature results. Temperature results were also sensitive to the model bathymetry, and additional investigations into segments widths and water depths may improve temperature predictions. Water quality constituent data were largely lacking for the system. Many estimation techniques and approximations were used for input water quality constituents for the model upstream boundary and tributaries when little or no data were available, introducing uncertainty to the model. It was not possible to calibrate pH to field data because alkalinity data were essentially unavailable. However, other constituents had good agreement between model predictions and field data, including dissolved oxygen, nitrates, total phosphorus, and total suspended solids. Title: Hydrodynamic and Water Quality Modeling of the Chehalis River Using CE-QUAL-W2 Author: Van Glubt, Sarah Year: 2017 The Chehalis River Basin is located in the southwest region of Washington State, originating in the Olympic Mountains and flowing to Grays Harbor and the Pacific Ocean. The Chehalis River is over 125 miles, exists within five counties, and flows through agricultural, residential, industrial, and forest land areas. Four major rivers discharge to the Chehalis River, as well as many smaller creeks, five wastewater treatment plants, and groundwater flows. Flooding is a major problem in the relatively flat areas surrounding the cities of Chehalis and Centralia, with severe consequences for property, safety and transportation. As a result, construction of a flood-control dam in the upper basin has been proposed. One major concern of constructing a dam is the potentially severe impacts to fish health and habitat. The Chehalis River has routinely violated water quality standards for primarily temperature and dissolved oxygen, and has had multiple water quality and Total Maximum Daily Load studies beginning in 1990. CE-QUAL-W2, a two-dimensional (longitudinal and vertical) hydrodynamic and water quality model, was used to simulate the Chehalis River, including free flowing river stretches and stratified (in summer) lake-like stretches. The goals of this research were to assess the flood retention structure's impacts to water quality, as well as river responses to potential climate change scenarios. In order to use the model to achieve these goals, calibration to field data for flow, temperature, and water quality constituents was performed. This involved developing meteorological data, riparian shading data, and flow, temperature, water quality records for all tributaries during the calibration period of January 1, 2013 to December 31, 2014. System cross-sectional geometry data were also required for the model grid. Because of the short travel time in the river, the model was sensitive to boundary condition data, wind speed, bathymetry, nutrient kinetics, and algae, epiphyton, and zooplankton kinetics. Future conditions showed predictions of warmer water temperatures and slight changes to water quality conditions on the river. As fish in the area prefer cooler water temperatures, this could pose a threat to fish health and habitat. Flood retention structures also showed impacts to river temperature and water quality. Structures with the purpose of flood retention only (only operating during times of flooding) gave model predictions for daily maximum temperature higher than structures that employed flood retention and flow augmentation (operating during all times of the year). This suggested the management of flow passage or retention by the dam is important for water quality on the river. As this research continues improvements will be made, particularly to temperature and water quality constituents. Additional data for the system would be beneficial to this process. Model predictions of temperature were sensitive to meteorological data, including cloud cover, which were largely estimated based on solar radiation. Additional meteorological data throughout the basin would be useful to temperature results. Temperature results were also sensitive to the model bathymetry, and additional investigations into segments widths and water depths may improve temperature predictions. Water quality constituent data were largely lacking for the system. Many estimation techniques and approximations were used for input water quality constituents for the model upstream boundary and tributaries when little or no data were available, introducing uncertainty to the model. It was not possible to calibrate pH to field data because alkalinity data were essentially unavailable. However, other constituents had good agreement between model predictions and field data, including dissolved oxygen, nitrates, total phosphorus, and total suspended solids. Close

• 17. [Article] Tidal Asymmetry in an Estuarine Pycnocline 2. Transport

  Flood currents in shallow estuaries are driven by an along-channel barotropic and baroclinic pressure gradient that increases monotonically toward the bottom, while friction retards near-bottom currents. ...

  Citation × Citation Citation Abstract Copy Title: Tidal Asymmetry in an Estuarine Pycnocline 2. Transport Author: Jay, David A., Cudaback, Cynthia N. Year: 2001 Flood currents in shallow estuaries are driven by an along-channel barotropic and baroclinic pressure gradient that increases monotonically toward the bottom, while friction retards near-bottom currents. Therefore, in many estuaries there is a middepth maximum in flood currents. We explore this phenomenon using a simple three-layer model in which each layer has vertically uniform currents and constant density. In this model the middle layer is of intermediate density and grows by shear-induced entrainment from the other two layers. This very simple model produces a middepth maximum in flood currents and simulates observed currents in the Columbia River entrance channel within about 10%. There is good qualitative agreement between model salinity transport and observed transport. The model pycnocline rises and falls tidally, in phase with the observed pycnocline, although pycnocline depth and thickness are better simulated using results from a two-layer model Title: Tidal Asymmetry in an Estuarine Pycnocline 2. Transport Author: Jay, David A., Cudaback, Cynthia N. Year: 2001 Flood currents in shallow estuaries are driven by an along-channel barotropic and baroclinic pressure gradient that increases monotonically toward the bottom, while friction retards near-bottom currents. Therefore, in many estuaries there is a middepth maximum in flood currents. We explore this phenomenon using a simple three-layer model in which each layer has vertically uniform currents and constant density. In this model the middle layer is of intermediate density and grows by shear-induced entrainment from the other two layers. This very simple model produces a middepth maximum in flood currents and simulates observed currents in the Columbia River entrance channel within about 10%. There is good qualitative agreement between model salinity transport and observed transport. The model pycnocline rises and falls tidally, in phase with the observed pycnocline, although pycnocline depth and thickness are better simulated using results from a two-layer model Close

• 18. [Article] Effects of urbanization on the hydrologic regime of Johnson Creek, Portland, Oregon

  The Johnson Creek watershed, Portland, Oregon, has undergone urbanization at an increasing rate. Excessive flooding has occurred in the lower portions of the watershed, resulting in an estimated 1.5 million ...

  Citation × Citation Citation Abstract Copy Title: Effects of urbanization on the hydrologic regime of Johnson Creek, Portland, Oregon Author: Clement, William Vandewater Year: 1984 The Johnson Creek watershed, Portland, Oregon, has undergone urbanization at an increasing rate. Excessive flooding has occurred in the lower portions of the watershed, resulting in an estimated 1.5 million dollars worth of flood losses annually. In attempts to mitigate the flooding damages millions of dollars have been spent to channelize the creek, and over 200 thousand dollars has been spent during the last 20 years on preliminary feasibility studies alone. The author saw a need to verify that there has been a change in the rainfall-runoff relationships in the upper Johnson Creek basin since 1941 and to quantify this change through the analysis of key hydrologic parameters. To accomplish this , extensive background research was conducted to gather as much extant information as possible about the climatic and physiographic characteristics that affect the basin hydrology. The watershed was found to have many distinct physiographic sub-areas comprised of different underlying geology, soils, geomorphic areas, slopes, vegetation patterns, and land use types that result in a complex interaction between the watershed input {precipitation) and the watershed output (runoff at the stream gage). Title: Effects of urbanization on the hydrologic regime of Johnson Creek, Portland, Oregon Author: Clement, William Vandewater Year: 1984 The Johnson Creek watershed, Portland, Oregon, has undergone urbanization at an increasing rate. Excessive flooding has occurred in the lower portions of the watershed, resulting in an estimated 1.5 million dollars worth of flood losses annually. In attempts to mitigate the flooding damages millions of dollars have been spent to channelize the creek, and over 200 thousand dollars has been spent during the last 20 years on preliminary feasibility studies alone. The author saw a need to verify that there has been a change in the rainfall-runoff relationships in the upper Johnson Creek basin since 1941 and to quantify this change through the analysis of key hydrologic parameters. To accomplish this , extensive background research was conducted to gather as much extant information as possible about the climatic and physiographic characteristics that affect the basin hydrology. The watershed was found to have many distinct physiographic sub-areas comprised of different underlying geology, soils, geomorphic areas, slopes, vegetation patterns, and land use types that result in a complex interaction between the watershed input {precipitation) and the watershed output (runoff at the stream gage). Close

• 19. [Article] Floodplains: Balancing Nature and Human Needs

  For countless years, the interaction between climatic conditions and water flow has forged the rolling hills and rivers in the metroscape. The floods that forced a deluge of water down the Columbia River ...

  Citation × Citation Citation Abstract Copy Title: Floodplains: Balancing Nature and Human Needs Author: Shandas, Vivek, Merrick, Meg Year: 2008 For countless years, the interaction between climatic conditions and water flow has forged the rolling hills and rivers in the metroscape. The floods that forced a deluge of water down the Columbia River between 13 and 17 thousand years ago established the fertile and absorptive landscape of the Willamette Valley. The lush vegetation controlled the regional climate and stabilized the soils, while the thirsty wetlands reduced flood potential, provided habitat, and purified the water. Over geological time, these natural processes have created ideal conditions for humans. The Pacific Northwest was home to some of the most densely populated communities of Native Americans, due partly to mild climate, plentiful water, and abundant sources of food and shelter. In the 19th century, Anglo settlers flooded the region for the same amenities, which continues to create ideal conditions for all that the region is known for today, including hiking, kayaking, and sailing - not to mention the provision of climate, topography, and fertile soils for growing some of the world?s best wines! Land surveys from the 1860s suggest that the current form of the metroscape started to take shape at the end of the 19th century. The conifers, alders, and maples that covered the region were slowly removed to make way for new urban settlements, and wetlands were drained to create farms and agricultural areas. In this atlas, we journey 140 years into the past to examine how and where the metroscape has changed. Our aim is to illustrate historic flooding of the region, and ponder what changes might mean to its future. Title: Floodplains: Balancing Nature and Human Needs Author: Shandas, Vivek, Merrick, Meg Year: 2008 For countless years, the interaction between climatic conditions and water flow has forged the rolling hills and rivers in the metroscape. The floods that forced a deluge of water down the Columbia River between 13 and 17 thousand years ago established the fertile and absorptive landscape of the Willamette Valley. The lush vegetation controlled the regional climate and stabilized the soils, while the thirsty wetlands reduced flood potential, provided habitat, and purified the water. Over geological time, these natural processes have created ideal conditions for humans. The Pacific Northwest was home to some of the most densely populated communities of Native Americans, due partly to mild climate, plentiful water, and abundant sources of food and shelter. In the 19th century, Anglo settlers flooded the region for the same amenities, which continues to create ideal conditions for all that the region is known for today, including hiking, kayaking, and sailing - not to mention the provision of climate, topography, and fertile soils for growing some of the world?s best wines! Land surveys from the 1860s suggest that the current form of the metroscape started to take shape at the end of the 19th century. The conifers, alders, and maples that covered the region were slowly removed to make way for new urban settlements, and wetlands were drained to create farms and agricultural areas. In this atlas, we journey 140 years into the past to examine how and where the metroscape has changed. Our aim is to illustrate historic flooding of the region, and ponder what changes might mean to its future. Close

• 20. [Article] Temporal Variations of Citizens’ Demands on Flood Damage Mitigation, Streamflow Quantity and Quality in the Korean Urban Watershed

  Sustainable watershed management (SWM) can be achieved through recognition and reflection upon the values of citizens. Collaborative governance consisting of citizens is crucial for successful SWM. Collaborative ...

  Citation × Citation Citation Abstract Copy Title: Temporal Variations of Citizens’ Demands on Flood Damage Mitigation, Streamflow Quantity and Quality in the Korean Urban Watershed Author: Hong, Change-Yu, Chung, Eun-Sung Year: 2016 Sustainable watershed management (SWM) can be achieved through recognition and reflection upon the values of citizens. Collaborative governance consisting of citizens is crucial for successful SWM. Collaborative governance definitely requires an active participatory decision-making process that reflects citizens’ preferences. Citizen preference also tends to substantially change with life pattern and life quality. These shifts can be caused by slight variations in both social priorities and personal preferences for SWM. Therefore, collaborative water governance must be frequently renewed in response to citizens’ values through the participatory framework. The An’yang Stream in South Korea is generally regarded as a representative urban stream restoration case that has been successfully led by collaborative governance. By conducting individual surveys with citizens on-site, this study addresses how citizens’ preferences of the stream’s management have changed between 2005 and 2015. In addition, this study used three quantitative hydrologic vulnerability indices: potential flood damage (PFD), potential streamflow depletion (PSD), and potential water quality deterioration (PWQD). They can spatially quantify citizen preference using the Analytic Hierarchy Process (AHP), which can systematically derive citizens’ subjective relative-weighted preferences. In the end, this study identified critical differences in priorities in regard to vulnerable areas between in 2005 and in 2015. Title: Temporal Variations of Citizens’ Demands on Flood Damage Mitigation, Streamflow Quantity and Quality in the Korean Urban Watershed Author: Hong, Change-Yu, Chung, Eun-Sung Year: 2016 Sustainable watershed management (SWM) can be achieved through recognition and reflection upon the values of citizens. Collaborative governance consisting of citizens is crucial for successful SWM. Collaborative governance definitely requires an active participatory decision-making process that reflects citizens’ preferences. Citizen preference also tends to substantially change with life pattern and life quality. These shifts can be caused by slight variations in both social priorities and personal preferences for SWM. Therefore, collaborative water governance must be frequently renewed in response to citizens’ values through the participatory framework. The An’yang Stream in South Korea is generally regarded as a representative urban stream restoration case that has been successfully led by collaborative governance. By conducting individual surveys with citizens on-site, this study addresses how citizens’ preferences of the stream’s management have changed between 2005 and 2015. In addition, this study used three quantitative hydrologic vulnerability indices: potential flood damage (PFD), potential streamflow depletion (PSD), and potential water quality deterioration (PWQD). They can spatially quantify citizen preference using the Analytic Hierarchy Process (AHP), which can systematically derive citizens’ subjective relative-weighted preferences. In the end, this study identified critical differences in priorities in regard to vulnerable areas between in 2005 and in 2015. Close

• 21. [Article] Overcoming Uncertainty and Barriers to Adoption of Blue-Green Infrastructure for Urban Flood Risk Management

  Blue-Green Infrastructure (BGI) and Sustainable Drainage Systems (SuDS) are increasingly recognised as vital components of urban flood risk management. However, uncertainty regarding their hydrologic performance ...

  Citation × Citation Citation Abstract Copy Title: Overcoming Uncertainty and Barriers to Adoption of Blue-Green Infrastructure for Urban Flood Risk Management Author: Thorne, Colin R., Lawson, E. C., Ozawa, Connie P., Hamlin, Samantha, Smith, Leonard A. Year: 2015 Blue-Green Infrastructure (BGI) and Sustainable Drainage Systems (SuDS) are increasingly recognised as vital components of urban flood risk management. However, uncertainty regarding their hydrologic performance and lack of confidence concerning their public acceptability create concerns and challenges that limit their widespread adoption. This paper investigates barriers to implementation of BGI in Portland, Oregon, using the Relevant Dominant Uncertainty (RDU) approach. Two types of RDU are identified: scientific RDUs related to physical processes that affect infrastructure performance and service provision, and socio-political RDUs that reflect a lack of confidence in socio-political structures and public preferences for BGI. We find that socio-political RDUs currently exert the strongest negative influences on BGI decision making in Portland.We conclude that identification and management of both biophysical and socio-political uncertainties are essential to broadening the implementation of BGI and sustainable urban flood risk management solutions that are practical, scientifically sound, and supported by local stakeholders. Title: Overcoming Uncertainty and Barriers to Adoption of Blue-Green Infrastructure for Urban Flood Risk Management Author: Thorne, Colin R., Lawson, E. C., Ozawa, Connie P., Hamlin, Samantha, Smith, Leonard A. Year: 2015 Blue-Green Infrastructure (BGI) and Sustainable Drainage Systems (SuDS) are increasingly recognised as vital components of urban flood risk management. However, uncertainty regarding their hydrologic performance and lack of confidence concerning their public acceptability create concerns and challenges that limit their widespread adoption. This paper investigates barriers to implementation of BGI in Portland, Oregon, using the Relevant Dominant Uncertainty (RDU) approach. Two types of RDU are identified: scientific RDUs related to physical processes that affect infrastructure performance and service provision, and socio-political RDUs that reflect a lack of confidence in socio-political structures and public preferences for BGI. We find that socio-political RDUs currently exert the strongest negative influences on BGI decision making in Portland.We conclude that identification and management of both biophysical and socio-political uncertainties are essential to broadening the implementation of BGI and sustainable urban flood risk management solutions that are practical, scientifically sound, and supported by local stakeholders. Close

• 22. [Article] Ecosystem Recovery in Estuarine Wetlands of the Columbia River Estuary

  In the restoration of tidal wetland ecosystems, potential drivers of plant community development range from biotic controls (e.g. plant competition, seed dispersal) to abiotic controls (e.g. tidal flooding, ...

  Citation × Citation Citation Abstract Copy Title: Ecosystem Recovery in Estuarine Wetlands of the Columbia River Estuary Author: Kidd, Sarah Ann Year: 2017 In the restoration of tidal wetland ecosystems, potential drivers of plant community development range from biotic controls (e.g. plant competition, seed dispersal) to abiotic controls (e.g. tidal flooding, salinity levels). How these controls influence the success of tidal wetland restoration are only partly understood, but have important implications for wetland habitat recovery. Specifically, the extent to which the existing native and non-native seed banks in tidally reconnected wetlands interact with these controls is not clear, yet the potential success of passive restoration methods depends upon this understanding. For a 54-year chronosequence of eleven tidal wetland restoration sites in the Lower Columbia River of western Oregon, USA, it was hypothesized that native plant species and soil properties would show trends approaching reference levels within 3 to 20 years post-restoration and that lower elevation wetland areas within restored sites would exhibit a greater native species abundance and similarity to reference sites, compared with restored high elevation wetland areas. Results indicated that plant species richness, soil organic matter, bulk density, pH, and salinity conditions among the restoration sites reached reference wetland ranges within 3-6 years post-tidal reconnection. The mid-low marsh elevation zones (2.5 m) remained dominated by non-native species Phalaris arundinacea and Juncus effusus subsp. effusus. To investigate the mechanisms driving these non-native plant invasions, it was hypothesized that native and non-native wetland plant community distributions would be reflective both of their abundance in the seed bank and of their germination tolerance to wetland tidal flooding and salinity conditions. Using a factorial study design of three tidal conditions by three salinity levels, these hypotheses were tested in the greenhouse. Overall, non-native seeds were found to significantly outnumber native seeds in both seed banks. In the greenhouse, P. arundinacea and J. effusus were found to germinate more readily out of the seed bank under freshwater high-marsh flooding (1 hour a day) treatments as compared to oligohaline (3 ppt) mid-low marsh flooding (3-6 hours twice a day) treatments and to brackish salinity (10 ppt) treatments. Dominant native wetland species, Carex lyngbyei and Schoenoplectus lacustris, germination were not found to vary significantly among the treatments (p > 0.10). These results indicate that the salinity and flooding gradients within these restored marshes suppress germination of the non-native species in the low-mid marsh but not in the high marsh, where they are likely able to outcompete the native species due to their dominance in the seed bank. The implications of these results for passive tidal wetland restoration efforts are that both seed bank composition and species-specific tolerances to restored tidal flooding and salinity gradients are key mechanisms driving native and non-native plant community development and resilience. Title: Ecosystem Recovery in Estuarine Wetlands of the Columbia River Estuary Author: Kidd, Sarah Ann Year: 2017 In the restoration of tidal wetland ecosystems, potential drivers of plant community development range from biotic controls (e.g. plant competition, seed dispersal) to abiotic controls (e.g. tidal flooding, salinity levels). How these controls influence the success of tidal wetland restoration are only partly understood, but have important implications for wetland habitat recovery. Specifically, the extent to which the existing native and non-native seed banks in tidally reconnected wetlands interact with these controls is not clear, yet the potential success of passive restoration methods depends upon this understanding. For a 54-year chronosequence of eleven tidal wetland restoration sites in the Lower Columbia River of western Oregon, USA, it was hypothesized that native plant species and soil properties would show trends approaching reference levels within 3 to 20 years post-restoration and that lower elevation wetland areas within restored sites would exhibit a greater native species abundance and similarity to reference sites, compared with restored high elevation wetland areas. Results indicated that plant species richness, soil organic matter, bulk density, pH, and salinity conditions among the restoration sites reached reference wetland ranges within 3-6 years post-tidal reconnection. The mid-low marsh elevation zones (2.5 m) remained dominated by non-native species Phalaris arundinacea and Juncus effusus subsp. effusus. To investigate the mechanisms driving these non-native plant invasions, it was hypothesized that native and non-native wetland plant community distributions would be reflective both of their abundance in the seed bank and of their germination tolerance to wetland tidal flooding and salinity conditions. Using a factorial study design of three tidal conditions by three salinity levels, these hypotheses were tested in the greenhouse. Overall, non-native seeds were found to significantly outnumber native seeds in both seed banks. In the greenhouse, P. arundinacea and J. effusus were found to germinate more readily out of the seed bank under freshwater high-marsh flooding (1 hour a day) treatments as compared to oligohaline (3 ppt) mid-low marsh flooding (3-6 hours twice a day) treatments and to brackish salinity (10 ppt) treatments. Dominant native wetland species, Carex lyngbyei and Schoenoplectus lacustris, germination were not found to vary significantly among the treatments (p > 0.10). These results indicate that the salinity and flooding gradients within these restored marshes suppress germination of the non-native species in the low-mid marsh but not in the high marsh, where they are likely able to outcompete the native species due to their dominance in the seed bank. The implications of these results for passive tidal wetland restoration efforts are that both seed bank composition and species-specific tolerances to restored tidal flooding and salinity gradients are key mechanisms driving native and non-native plant community development and resilience. Close

• 23. [Article] Seaside, Oregon, Tsunami Pilot Study : Modernization of FEMA Flood Hazard Maps

  FEMA Flood Insurance Rate Map (FIRM) guidelines do not currently exist for conducting and incorporating tsunami hazard assessments that reflect the substantial advances in tsunami research achieved in ...

  Citation × Citation Citation Abstract Copy Title: Seaside, Oregon, Tsunami Pilot Study : Modernization of FEMA Flood Hazard Maps Author: González, Frank I, Geist, Eric L., Synolakis, Costas, Arcas, Diego Rodriguez, Bellomo, Douglas, Carlton, David, Horning, Thomas, Jaffe, Bruce, Johnson, Jeff, Kânoğlu, Utku, Mofjeld, Harold O., Newman, Jean, Parsons, Thomas, Peters, Robert, Peterson, Curt D., Priest, George, Titov, Vasily V., Venturato, Angie J., Weber, Joseph, Wong, Florence L., Yalçıner, Ahmet Year: 2006 FEMA Flood Insurance Rate Map (FIRM) guidelines do not currently exist for conducting and incorporating tsunami hazard assessments that reflect the substantial advances in tsunami research achieved in the last two decades; this conclusion is the result of two FEMA-sponsored workshops and the associated Tsunami Focused Study (Chowdhury et al., 2005). Therefore, as part of FEMA's Map Modernization Program, a Tsunami Pilot Study was carried out in the Seaside/Gearhart, Oregon, area to develop an improved Probabilistic Tsunami Hazard Assessment (PTHA) methodology and to provide recommendations for improved tsunami hazard assessment guidelines. The Seaside area was chosen because it is typical of many coastal communities in the section of the Pacific Coast from Cape Mendocino to the Strait of Juan de Fuca, and because State Agencies and local stakeholders expressed considerable interest in mapping the tsunami threat to this area. The study was an interagency effort by FEMA, U.S. Geological Survey, and the National Oceanic and Atmospheric Administration, in collaboration with the University of Southern California, Middle East Technical University, Portland State University, Horning Geoscience, Northwest Hydraulics Consultants, and the Oregon Department of Geological and Mineral Industries. Title: Seaside, Oregon, Tsunami Pilot Study : Modernization of FEMA Flood Hazard Maps Author: González, Frank I, Geist, Eric L., Synolakis, Costas, Arcas, Diego Rodriguez, Bellomo, Douglas, Carlton, David, Horning, Thomas, Jaffe, Bruce, Johnson, Jeff, Kânoğlu, Utku, Mofjeld, Harold O., Newman, Jean, Parsons, Thomas, Peters, Robert, Peterson, Curt D., Priest, George, Titov, Vasily V., Venturato, Angie J., Weber, Joseph, Wong, Florence L., Yalçıner, Ahmet Year: 2006 FEMA Flood Insurance Rate Map (FIRM) guidelines do not currently exist for conducting and incorporating tsunami hazard assessments that reflect the substantial advances in tsunami research achieved in the last two decades; this conclusion is the result of two FEMA-sponsored workshops and the associated Tsunami Focused Study (Chowdhury et al., 2005). Therefore, as part of FEMA's Map Modernization Program, a Tsunami Pilot Study was carried out in the Seaside/Gearhart, Oregon, area to develop an improved Probabilistic Tsunami Hazard Assessment (PTHA) methodology and to provide recommendations for improved tsunami hazard assessment guidelines. The Seaside area was chosen because it is typical of many coastal communities in the section of the Pacific Coast from Cape Mendocino to the Strait of Juan de Fuca, and because State Agencies and local stakeholders expressed considerable interest in mapping the tsunami threat to this area. The study was an interagency effort by FEMA, U.S. Geological Survey, and the National Oceanic and Atmospheric Administration, in collaboration with the University of Southern California, Middle East Technical University, Portland State University, Horning Geoscience, Northwest Hydraulics Consultants, and the Oregon Department of Geological and Mineral Industries. Close

• 24. [Article] Residual Circulation in Shallow Estuaries 1. Highly Stratified, Narrow Estuaries

  Long-wave theory and simple turbulence closures have been used to show that three distinct types of circulation (highly stratified, weakly stratified, and partially mixed) arise in narrow, shallow estuaries ...

  Citation × Citation Citation Abstract Copy Title: Residual Circulation in Shallow Estuaries 1. Highly Stratified, Narrow Estuaries Author: Jay, David A., Smith, J. Dungan Year: 1990 Long-wave theory and simple turbulence closures have been used to show that three distinct types of circulation (highly stratified, weakly stratified, and partially mixed) arise in narrow, shallow estuaries from the finite amplitude of the tide and the interaction of stratification with vertical mixing. Each type has a different dominant process causing the vertical exchange of salt and fresh water on the flood, and each gives rise to a characteristic residual circulation. The tidal circulation in highly stratified shallow estuaries, described herein, is the result of a finite amplitude internal motion driven by the barotropic tide; shear instabilities at the interface are the major vertical exchange mechanism. The residual circulation is caused primarily by ebb-flood asymmetry in interface position and thickness. A model based on our theoretical analysis shows that the interface thickness on flood is much less than the depth of flow up to a critical tidal amplitude at which the two-layer flow is destroyed, and correctly predicts the tidal amplitude of the neap-spring transition in the Columbia River Estuary. Tidal frequency internal wave motion is not found in weakly stratified and partially mixed estuaries. Because of the reduced tidal shear, shear instabilities are weak or absent, and the residual circulation assumes a very different character, as described in part 2. Title: Residual Circulation in Shallow Estuaries 1. Highly Stratified, Narrow Estuaries Author: Jay, David A., Smith, J. Dungan Year: 1990 Long-wave theory and simple turbulence closures have been used to show that three distinct types of circulation (highly stratified, weakly stratified, and partially mixed) arise in narrow, shallow estuaries from the finite amplitude of the tide and the interaction of stratification with vertical mixing. Each type has a different dominant process causing the vertical exchange of salt and fresh water on the flood, and each gives rise to a characteristic residual circulation. The tidal circulation in highly stratified shallow estuaries, described herein, is the result of a finite amplitude internal motion driven by the barotropic tide; shear instabilities at the interface are the major vertical exchange mechanism. The residual circulation is caused primarily by ebb-flood asymmetry in interface position and thickness. A model based on our theoretical analysis shows that the interface thickness on flood is much less than the depth of flow up to a critical tidal amplitude at which the two-layer flow is destroyed, and correctly predicts the tidal amplitude of the neap-spring transition in the Columbia River Estuary. Tidal frequency internal wave motion is not found in weakly stratified and partially mixed estuaries. Because of the reduced tidal shear, shear instabilities are weak or absent, and the residual circulation assumes a very different character, as described in part 2. Close

• 25. [Article] Suspended Sediment Fluxes at an Intertidal Flat: The Shifting Influence of Wave, Wind, Tidal, and Freshwater Forcing

  Using in situ, continuous, high frequency (8–16 Hz) measurements of velocity, suspended sediment concentration (SSC), and salinity, we investigate the factors affecting near-bed sediment flux during and ...

  Citation × Citation Citation Abstract Copy Title: Suspended Sediment Fluxes at an Intertidal Flat: The Shifting Influence of Wave, Wind, Tidal, and Freshwater Forcing Author: Talke, Stefan A., Stacey, Mark T. Year: 2008 Using in situ, continuous, high frequency (8–16 Hz) measurements of velocity, suspended sediment concentration (SSC), and salinity, we investigate the factors affecting near-bed sediment flux during and after a meteorological event (cold front) on an intertidal flat in central San Francisco Bay. Hydrodynamic forcing occurs over many frequency bands including wind wave, ocean swell, seiching (500–1000 s), tidal, and infra-tidal frequencies, and varies greatly over the time scale of hours and days. Sediment fluxes occur primarily due to variations in flow and SSC at three different scales: residual (tidally averaged), tidal, and seiching. During the meteorological event, sediment fluxes are dominated by increases in tidally averaged SSC and flow. Runoff and wind-induced circulation contribute to an order of magnitude increase in tidally averaged offshore flow, while waves and seiching motions from wind forcing cause an order of magnitude increase in tidally averaged SSC. Sediment fluxes during calm periods are dominated by asymmetries in SSC over a tidal cycle. Freshwater forcing produces sharp salinity fronts which trap sediment and sweep by the sensors over short (∼30 min) time scales, and occur primarily during the flood. The resulting flood dominance in SSC is magnified or reversed by variations in wind forcing between the flood and ebb. Long-term records show that more than half of wind events (sustained speeds of greater than 5 m/s) occur for 3 h or less, suggesting that asymmetric wind forcing over a tidal cycle commonly occurs. Seiching associated with wind and its variation produces onshore sediment transport. Overall, the changing hydrodynamic and meteorological forcing influence sediment flux at both short (minutes) and long (days) time scales. Title: Suspended Sediment Fluxes at an Intertidal Flat: The Shifting Influence of Wave, Wind, Tidal, and Freshwater Forcing Author: Talke, Stefan A., Stacey, Mark T. Year: 2008 Using in situ, continuous, high frequency (8–16 Hz) measurements of velocity, suspended sediment concentration (SSC), and salinity, we investigate the factors affecting near-bed sediment flux during and after a meteorological event (cold front) on an intertidal flat in central San Francisco Bay. Hydrodynamic forcing occurs over many frequency bands including wind wave, ocean swell, seiching (500–1000 s), tidal, and infra-tidal frequencies, and varies greatly over the time scale of hours and days. Sediment fluxes occur primarily due to variations in flow and SSC at three different scales: residual (tidally averaged), tidal, and seiching. During the meteorological event, sediment fluxes are dominated by increases in tidally averaged SSC and flow. Runoff and wind-induced circulation contribute to an order of magnitude increase in tidally averaged offshore flow, while waves and seiching motions from wind forcing cause an order of magnitude increase in tidally averaged SSC. Sediment fluxes during calm periods are dominated by asymmetries in SSC over a tidal cycle. Freshwater forcing produces sharp salinity fronts which trap sediment and sweep by the sensors over short (∼30 min) time scales, and occur primarily during the flood. The resulting flood dominance in SSC is magnified or reversed by variations in wind forcing between the flood and ebb. Long-term records show that more than half of wind events (sustained speeds of greater than 5 m/s) occur for 3 h or less, suggesting that asymmetric wind forcing over a tidal cycle commonly occurs. Seiching associated with wind and its variation produces onshore sediment transport. Overall, the changing hydrodynamic and meteorological forcing influence sediment flux at both short (minutes) and long (days) time scales. Close

• 26. [Article] The Impacts of Natural Flood Management Approaches on In-Channel Sediment Quality

  Natural Flood Management (NFM) techniques aim to reduce downstream flooding by storing and slowing the flow of stormwater to river channels. These techniques include a range of measures, including setback ...

  Citation × Citation Citation Abstract Copy Title: The Impacts of Natural Flood Management Approaches on In-Channel Sediment Quality Author: Janes, Victoria, Grabowski, Robert, Mant, J., Allen, Deonie Year: 2017 Natural Flood Management (NFM) techniques aim to reduce downstream flooding by storing and slowing the flow of stormwater to river channels. These techniques include a range of measures, including setback stormwater outfalls and the physical restoration of channels and floodplains, to improve the natural functioning of catchments. An additional benefit of NFM measures is the potential reduction in sediment and pollutant delivery to the channel. Urban development releases a variety of heavy metal and nutrient pollutants that enter rivers through stormwater outfalls with adverse effects on the aquatic ecosystem. In this study, the influence of channel modification and quality of the river habitat on the sediment quality surrounding stormwater outfalls was assessed. Sediment samples were taken at several outfalls within the Johnson Creek catchment, Oregon, USA, and analysed for a variety of urban pollutants. The level of river habitat quality and modification at each site were assessed using a semi-quantitative scoring methodology. Significant increases in pollutant levels were observed at outfalls, with a greater and more variable increase at direct compared to setback outfalls. Removal efficiency of certain pollutants was found to be significantly correlated to the level of habitat quality or modification (for Fe, Ba, Sn, Mg, P, K) indicating that more natural reaches had greater potential for pollutant removal. The findings highlight the multiple benefits associated with NFM and river restoration approaches in relation to sediment quality and pollutant content. Title: The Impacts of Natural Flood Management Approaches on In-Channel Sediment Quality Author: Janes, Victoria, Grabowski, Robert, Mant, J., Allen, Deonie Year: 2017 Natural Flood Management (NFM) techniques aim to reduce downstream flooding by storing and slowing the flow of stormwater to river channels. These techniques include a range of measures, including setback stormwater outfalls and the physical restoration of channels and floodplains, to improve the natural functioning of catchments. An additional benefit of NFM measures is the potential reduction in sediment and pollutant delivery to the channel. Urban development releases a variety of heavy metal and nutrient pollutants that enter rivers through stormwater outfalls with adverse effects on the aquatic ecosystem. In this study, the influence of channel modification and quality of the river habitat on the sediment quality surrounding stormwater outfalls was assessed. Sediment samples were taken at several outfalls within the Johnson Creek catchment, Oregon, USA, and analysed for a variety of urban pollutants. The level of river habitat quality and modification at each site were assessed using a semi-quantitative scoring methodology. Significant increases in pollutant levels were observed at outfalls, with a greater and more variable increase at direct compared to setback outfalls. Removal efficiency of certain pollutants was found to be significantly correlated to the level of habitat quality or modification (for Fe, Ba, Sn, Mg, P, K) indicating that more natural reaches had greater potential for pollutant removal. The findings highlight the multiple benefits associated with NFM and river restoration approaches in relation to sediment quality and pollutant content. Close

• 27. [Article] Holgate Lake Study: An Examination of the Issues Associated with Groundwater Flooding

  This project examines Holgate Lake. Despite its natural hazard characteristics, the Holgate Lake area has not been immune to development pressure. Holgate Lake is an intermittent water body that forms ...

  Citation × Citation Citation Abstract Copy Title: Holgate Lake Study: An Examination of the Issues Associated with Groundwater Flooding Author: Lynch, John J., Jr., Mader, Heidi A., McCann, Mark Year: 1999 This project examines Holgate Lake. Despite its natural hazard characteristics, the Holgate Lake area has not been immune to development pressure. Holgate Lake is an intermittent water body that forms when groundwater levels rise. Historical accounts show that the lake has formed at many different times in the last century. Because the lake fluctuates with the groundwater level, it is not necessarily present from year to year. As the area has developed, more and more people built in the location of the natural lakebed when the water was not present. When the lake level returned in the 1960's flooding of homes in the area became a significant concern. The water remained for up to three months at a time, causing people to leave their homes and belongings behind. A period of dry weather persisted through the 1970's and 1980's, which lowered the level of concern about the lake's potential impacts. Due in part to the lower level 0 concern, development continued to occur in the area. However, the concerns returned in 1996 and 1997 when the lake level rose and inundated the area. These events refocused the City of Portland's attention on this area and its flooding issues. Title: Holgate Lake Study: An Examination of the Issues Associated with Groundwater Flooding Author: Lynch, John J., Jr., Mader, Heidi A., McCann, Mark Year: 1999 This project examines Holgate Lake. Despite its natural hazard characteristics, the Holgate Lake area has not been immune to development pressure. Holgate Lake is an intermittent water body that forms when groundwater levels rise. Historical accounts show that the lake has formed at many different times in the last century. Because the lake fluctuates with the groundwater level, it is not necessarily present from year to year. As the area has developed, more and more people built in the location of the natural lakebed when the water was not present. When the lake level returned in the 1960's flooding of homes in the area became a significant concern. The water remained for up to three months at a time, causing people to leave their homes and belongings behind. A period of dry weather persisted through the 1970's and 1980's, which lowered the level of concern about the lake's potential impacts. Due in part to the lower level 0 concern, development continued to occur in the area. However, the concerns returned in 1996 and 1997 when the lake level rose and inundated the area. These events refocused the City of Portland's attention on this area and its flooding issues. Close

• 28. [Article] Emissions of Anaerobically Produced Methane by Trees

  Recent studies indicate that plants may be a previously overlooked but significant source of atmospheric CH₄, though there is considerable disagreement on the mechanism of production. Our work sought to ...

  Citation × Citation Citation Abstract Copy Title: Emissions of Anaerobically Produced Methane by Trees Author: Rice, Andrew L., Butenhoff, Christopher Lee, Shearer, Martha J., Teama, Doaa, Rosenstiel, Todd N., Khalil, M. A. K. Year: 2010 Recent studies indicate that plants may be a previously overlooked but significant source of atmospheric CH₄, though there is considerable disagreement on the mechanism of production. Our work sought to verify that woody deciduous trees grown under inundated conditions had the capacity for transporting CH₄ from an anaerobic subsurface to the atmosphere and to consider if such a source could be important globally. Here, we report results from a greenhouse mesocosm study that indicate significant emissions of anaerobically produced CH₄ transmitted to the atmosphere through broadleaf riparian tree species grown under flooded conditions. Using a leaf area normalized mean emission rate (0.7 ± 0.3 μg cm⁻² hr⁻¹), results were scaled globally for flooded forest regions and estimated to be 60 ± 20 Tg year⁻¹, ~10% of the global CH₄ source. The carbon isotopic composition of CH4 emitted was found to be significantly enriched compared with expectations (δ13C ~ −54‰) and provided an important isotopic constraint on the global source which coincides with the mean of the globally scaled greenhouse-based estimate. Title: Emissions of Anaerobically Produced Methane by Trees Author: Rice, Andrew L., Butenhoff, Christopher Lee, Shearer, Martha J., Teama, Doaa, Rosenstiel, Todd N., Khalil, M. A. K. Year: 2010 Recent studies indicate that plants may be a previously overlooked but significant source of atmospheric CH₄, though there is considerable disagreement on the mechanism of production. Our work sought to verify that woody deciduous trees grown under inundated conditions had the capacity for transporting CH₄ from an anaerobic subsurface to the atmosphere and to consider if such a source could be important globally. Here, we report results from a greenhouse mesocosm study that indicate significant emissions of anaerobically produced CH₄ transmitted to the atmosphere through broadleaf riparian tree species grown under flooded conditions. Using a leaf area normalized mean emission rate (0.7 ± 0.3 μg cm⁻² hr⁻¹), results were scaled globally for flooded forest regions and estimated to be 60 ± 20 Tg year⁻¹, ~10% of the global CH₄ source. The carbon isotopic composition of CH4 emitted was found to be significantly enriched compared with expectations (δ13C ~ −54‰) and provided an important isotopic constraint on the global source which coincides with the mean of the globally scaled greenhouse-based estimate. Close

• 29. [Article] The effect of human activity on the middle course of the Tualatin River, Oregon

  A diurnal study of biological, chemical, and physical parameters was made on the middle course of the, Tualatin River, which drains a 1840 km2 (711 mi2) basin adjacent to metropolitan Portland, Oregon. ...

  Citation × Citation Citation Abstract Copy Title: The effect of human activity on the middle course of the Tualatin River, Oregon Author: Carter, Lolita M. Year: 1975 A diurnal study of biological, chemical, and physical parameters was made on the middle course of the, Tualatin River, which drains a 1840 km2 (711 mi2) basin adjacent to metropolitan Portland, Oregon. This portion of the river lies along land in transition of use from rural agriculture to highly urbanized development. There is no nutrient loading of the river from farming practices because there was no return of water from summer, sprinkler irrigation of commercial crops. However, irrigation significantly reduces the volume of water in the river in the summers. Effluents from sewage treatment plants flowing into the tributaries that drain the highly urbanized eastern areas of the river basin are the main cause of degraded water quality and algal biomass in the lower reaches of the river. The Tualatin River above the mouth of Rock Creek is relatively unpolluted, but downstream from Rock Creek the river is highly eutrophic and during the periods of low flow in the summer serves as a sewage oxidation channel. In this same portion of the river there is also evidence that nitrification occurs. Winter floods leach nitrate-nitrogen from the basin, but in the summer the possibility exists. that nitrate-nitrogen may be a limiting nutrient for algal productivity in the river above Hillsboro. The principal source of poly-phosphates is from sewage treatment plant effluents, but concentrations of poly-phosphates in the middle reaches of the river indicate that there is a natural source of poly- and/or ortho-phosphates in the watershed. Removal of phosphorous compounds from the effluents probably would not affect the large algal blooms occurring in the river below Hillsboro. Trace metal analyses indicated that iron, potassium, nickel, zinc, lead, copper, cobalt, and chromium concentrations were higher during flooding. Turbidity readings suggest that these trace elements are deposited on the floodplain. Melted snow water, which caused one of the winter floods, contained concentrations of zinc, ·copper, and lead greater than those found in the river during the flood. Greater concentrations of arsenic and zinc came from farmland than from urban areas. Diversities of the net plankton as measured by the Shannon-Weaver Index did not change from season to season, nor with downstream flow. Species in the net plankton were benthic forms at the upper stations and planktonic forms downstream from Hillsboro, especially in the summer when the reduced flow caused the river to pond. The enriched effluents from Rock Creek did not affect the diversity of the organisms downstream, but supported a larger biomass. By rating the diversities with other studies it was found that the middle course of the Tualatin River is eutrophic but not heavily polluted. A diurnal study was especially valuable from April to September, inclusive, when insolation and temperatures favored biological activities such as photosynthesis and decomposition. From November to January little diurnal change in the water quality was found. Farming had its greatest impact in the quantity of water and municipalities had a more serious impact on the water quality in the middle course of the Tualatin River. Even with the reduced flow from agricultural irrigation, the river can maintain relatively good water quality, except when effluents from sewage plants caused highly eutrophic conditions. Title: The effect of human activity on the middle course of the Tualatin River, Oregon Author: Carter, Lolita M. Year: 1975 A diurnal study of biological, chemical, and physical parameters was made on the middle course of the, Tualatin River, which drains a 1840 km2 (711 mi2) basin adjacent to metropolitan Portland, Oregon. This portion of the river lies along land in transition of use from rural agriculture to highly urbanized development. There is no nutrient loading of the river from farming practices because there was no return of water from summer, sprinkler irrigation of commercial crops. However, irrigation significantly reduces the volume of water in the river in the summers. Effluents from sewage treatment plants flowing into the tributaries that drain the highly urbanized eastern areas of the river basin are the main cause of degraded water quality and algal biomass in the lower reaches of the river. The Tualatin River above the mouth of Rock Creek is relatively unpolluted, but downstream from Rock Creek the river is highly eutrophic and during the periods of low flow in the summer serves as a sewage oxidation channel. In this same portion of the river there is also evidence that nitrification occurs. Winter floods leach nitrate-nitrogen from the basin, but in the summer the possibility exists. that nitrate-nitrogen may be a limiting nutrient for algal productivity in the river above Hillsboro. The principal source of poly-phosphates is from sewage treatment plant effluents, but concentrations of poly-phosphates in the middle reaches of the river indicate that there is a natural source of poly- and/or ortho-phosphates in the watershed. Removal of phosphorous compounds from the effluents probably would not affect the large algal blooms occurring in the river below Hillsboro. Trace metal analyses indicated that iron, potassium, nickel, zinc, lead, copper, cobalt, and chromium concentrations were higher during flooding. Turbidity readings suggest that these trace elements are deposited on the floodplain. Melted snow water, which caused one of the winter floods, contained concentrations of zinc, ·copper, and lead greater than those found in the river during the flood. Greater concentrations of arsenic and zinc came from farmland than from urban areas. Diversities of the net plankton as measured by the Shannon-Weaver Index did not change from season to season, nor with downstream flow. Species in the net plankton were benthic forms at the upper stations and planktonic forms downstream from Hillsboro, especially in the summer when the reduced flow caused the river to pond. The enriched effluents from Rock Creek did not affect the diversity of the organisms downstream, but supported a larger biomass. By rating the diversities with other studies it was found that the middle course of the Tualatin River is eutrophic but not heavily polluted. A diurnal study was especially valuable from April to September, inclusive, when insolation and temperatures favored biological activities such as photosynthesis and decomposition. From November to January little diurnal change in the water quality was found. Farming had its greatest impact in the quantity of water and municipalities had a more serious impact on the water quality in the middle course of the Tualatin River. Even with the reduced flow from agricultural irrigation, the river can maintain relatively good water quality, except when effluents from sewage plants caused highly eutrophic conditions. Close

• 30. [Article] Sedimentologic changes in the deposits of an evolving lahar-flood in 2006, Hood River Basin, Mount Hood, Oregon

  Over a span of six days from November 2nd -- 7th, 2006 approximately 43 cm of precipitation fell over the Hood River Basin in Oregon. A lahar was initiated on the Eliot Branch of the Middle Fork Hood River ...

  Citation × Citation Citation Abstract Copy Title: Sedimentologic changes in the deposits of an evolving lahar-flood in 2006, Hood River Basin, Mount Hood, Oregon Author: Poole, Matthew Ray Year: 2016 Over a span of six days from November 2nd -- 7th, 2006 approximately 43 cm of precipitation fell over the Hood River Basin in Oregon. A lahar was initiated on the Eliot Branch of the Middle Fork Hood River by two or more landslides that occurred on the lateral moraines of the Eliot Glacier on the early part of November 7th, 2006. The Eliot Branch lahar was embedded within the larger regional flood that was occurring in the Hood River Basin and traveled a total of 48 km from the initiation points on the north flank of Mount Hood to the Hood Rivers confluence with the Columbia River. The initiating landslides abruptly transformed into a debris flow upon mixing with flood waters of the Eliot Branch. The debris flow traveled a distance of ~28 km at which point it was transformed first to a hyperconcentrated flow and then to water flow via selective deposition of coarse sediment and progressive dilution by channel flow waters from the East and West Fork Hood Rivers. The transformation from debris flow to hyperconcentrated streamflow was recorded by a thickening wedge of hyperconcentrated streamflow sediments found above and below progressively fining debris flow sediments over a reach of 22 km. Finally, the hyperconcentrated-flow phase of the lahar transformed to water flow and then traveled an additional 20 km to the Hood River delta. Upon reaching the apex of the Hood River delta, depositing sediments led to an expansion of the delta. Debris-flow sediments were predominantly gravel (36.0-69.7% by wt.) with sand (22.1-55.9% by wt.) and fines (4.7-7.8% by wt.). Hyperconcentrated flow deposits contained a larger sand fraction of (66.8-99.2% by wt.) with few gravel clasts (0-26.0% by wt.) and fines (0-8.8% by wt.). Water flow deposits averaged 90.5% (wt.) sand with 6.0% (wt.) gravel and 3.0% (wt.) fines. Sorting was a key factor in flow identification and showed progressive improvement downstream from the initiation point. Sorting values for the flow types are as follows: debris flow deposits ranged from 3.3Φ (very poorly sorted) to 1.8Φ (poorly sorted), hyperconcentrated flow deposits ranged from 2.4Φ (very poorly sorted) to 0.8Φ (moderately sorted), and water flood deposits ranged between 1.4Φ (poorly sorted) to 0.6Φ (moderately sorted). Title: Sedimentologic changes in the deposits of an evolving lahar-flood in 2006, Hood River Basin, Mount Hood, Oregon Author: Poole, Matthew Ray Year: 2016 Over a span of six days from November 2nd -- 7th, 2006 approximately 43 cm of precipitation fell over the Hood River Basin in Oregon. A lahar was initiated on the Eliot Branch of the Middle Fork Hood River by two or more landslides that occurred on the lateral moraines of the Eliot Glacier on the early part of November 7th, 2006. The Eliot Branch lahar was embedded within the larger regional flood that was occurring in the Hood River Basin and traveled a total of 48 km from the initiation points on the north flank of Mount Hood to the Hood Rivers confluence with the Columbia River. The initiating landslides abruptly transformed into a debris flow upon mixing with flood waters of the Eliot Branch. The debris flow traveled a distance of ~28 km at which point it was transformed first to a hyperconcentrated flow and then to water flow via selective deposition of coarse sediment and progressive dilution by channel flow waters from the East and West Fork Hood Rivers. The transformation from debris flow to hyperconcentrated streamflow was recorded by a thickening wedge of hyperconcentrated streamflow sediments found above and below progressively fining debris flow sediments over a reach of 22 km. Finally, the hyperconcentrated-flow phase of the lahar transformed to water flow and then traveled an additional 20 km to the Hood River delta. Upon reaching the apex of the Hood River delta, depositing sediments led to an expansion of the delta. Debris-flow sediments were predominantly gravel (36.0-69.7% by wt.) with sand (22.1-55.9% by wt.) and fines (4.7-7.8% by wt.). Hyperconcentrated flow deposits contained a larger sand fraction of (66.8-99.2% by wt.) with few gravel clasts (0-26.0% by wt.) and fines (0-8.8% by wt.). Water flow deposits averaged 90.5% (wt.) sand with 6.0% (wt.) gravel and 3.0% (wt.) fines. Sorting was a key factor in flow identification and showed progressive improvement downstream from the initiation point. Sorting values for the flow types are as follows: debris flow deposits ranged from 3.3Φ (very poorly sorted) to 1.8Φ (poorly sorted), hyperconcentrated flow deposits ranged from 2.4Φ (very poorly sorted) to 0.8Φ (moderately sorted), and water flood deposits ranged between 1.4Φ (poorly sorted) to 0.6Φ (moderately sorted). Close

• 31. [Article] Climate Change Impact on the Spatio-Temporal Variability of Hydro-Climate Extremes

  The rising temperature of the earth due to climate change has shown to alter the variations of hydro-climate variables, including their intensities, frequencies and durations. Extreme events such as floods ...

  Citation × Citation Citation Abstract Copy Title: Climate Change Impact on the Spatio-Temporal Variability of Hydro-Climate Extremes Author: Najafi, Mohammad Reza Year: 2013 The rising temperature of the earth due to climate change has shown to alter the variations of hydro-climate variables, including their intensities, frequencies and durations. Extreme events such as floods are, in particular, susceptible to any disturbances in climate cycles. As such it is important to provide policymakers with sufficient knowledge about the probable impacts of climate change on hydrologic extremes and most importantly on floods, which have the highest impacts on the societies. For this reason analysis of hydro-climate extremes is commonly performed using data at each site (or grid cell), however due to the limited number of extreme events, these analyses are not robust. Current methods, such as the regional frequency analysis, which combine data from different locations are incapable of incorporating the spatial structure of the data as well as other explanatory variables, and do not explicitly, assess the uncertainties. In this thesis the spatial hierarchical Bayesian model is proposed for hydro-climate extreme analyses using data recorded at each site or grid. This method combines limited number of data from different locations, estimates the uncertainties in different stages of the hierarchy, incorporates additional explanatory variables (covariates), and can be used to estimate extreme events at un-gaged sites. The first project develops a spatial hierarchical Bayesian method to model the extreme runoffs over two spatial domains in the Columbia River Basin, U.S. The model is also employed to estimate floods with different return levels within time slices of fifteen years in order to detect possible trends in runoff extremes. Continuing on the extreme analysis, the impact of climate change on runoff extremes is investigated over the whole Pacific Northwest (PNW). This study aims to address the question of how the runoff extremes will change in the future compared to the historical time period, investigate the different behaviors of the regional climate models (RCMs) regarding the runoff extremes, and assess the seasonal variations of runoff extremes. Given the increasing number of climate model simulations the goal of the third project is to provide a multi-model ensemble average of hydro-climate extremes and characterize the inherent uncertainties. Outputs from several regional climate models provided by NARCCAP are considered for the analysis in all seasons. Three combination scenarios are defined and compared for multi-modeling of extreme runoffs. The biases of each scenario are calculated and the scenario with the least bias is selected for projecting seasonal runoff extremes. The aim of the fourth project is to quantify and compare the uncertainties regarding global climate models to the ones from the hydrologic model structures in climate change impact studies. Various methods have been proposed to downscale the coarse resolution General Circulation Model (GCM) climatological variables to the fine scale regional variables; however fewer studies have been focused on the selection of GCM predictors. Additionally, the results obtained from one downscaling technique may not be robust and the uncertainties related to the downscaling scheme are not realized. To address these issues, in the fifth study we employed Independent Component Analysis (ICA) for predictor selection which determines spatially independent GCM variables (as discussed in Appendix A). Cross validation of the independent components is employed to find the predictor combination that describes the regional precipitation over the upper Willamette basin with minimum error. These climate variables along with the observed precipitation are used to calibrate three downscaling models: Multi Linear Regression (MLR), Support Vector Machine (SVM) and Adaptive-Network-Based Fuzzy Inference System (ANFIS). Title: Climate Change Impact on the Spatio-Temporal Variability of Hydro-Climate Extremes Author: Najafi, Mohammad Reza Year: 2013 The rising temperature of the earth due to climate change has shown to alter the variations of hydro-climate variables, including their intensities, frequencies and durations. Extreme events such as floods are, in particular, susceptible to any disturbances in climate cycles. As such it is important to provide policymakers with sufficient knowledge about the probable impacts of climate change on hydrologic extremes and most importantly on floods, which have the highest impacts on the societies. For this reason analysis of hydro-climate extremes is commonly performed using data at each site (or grid cell), however due to the limited number of extreme events, these analyses are not robust. Current methods, such as the regional frequency analysis, which combine data from different locations are incapable of incorporating the spatial structure of the data as well as other explanatory variables, and do not explicitly, assess the uncertainties. In this thesis the spatial hierarchical Bayesian model is proposed for hydro-climate extreme analyses using data recorded at each site or grid. This method combines limited number of data from different locations, estimates the uncertainties in different stages of the hierarchy, incorporates additional explanatory variables (covariates), and can be used to estimate extreme events at un-gaged sites. The first project develops a spatial hierarchical Bayesian method to model the extreme runoffs over two spatial domains in the Columbia River Basin, U.S. The model is also employed to estimate floods with different return levels within time slices of fifteen years in order to detect possible trends in runoff extremes. Continuing on the extreme analysis, the impact of climate change on runoff extremes is investigated over the whole Pacific Northwest (PNW). This study aims to address the question of how the runoff extremes will change in the future compared to the historical time period, investigate the different behaviors of the regional climate models (RCMs) regarding the runoff extremes, and assess the seasonal variations of runoff extremes. Given the increasing number of climate model simulations the goal of the third project is to provide a multi-model ensemble average of hydro-climate extremes and characterize the inherent uncertainties. Outputs from several regional climate models provided by NARCCAP are considered for the analysis in all seasons. Three combination scenarios are defined and compared for multi-modeling of extreme runoffs. The biases of each scenario are calculated and the scenario with the least bias is selected for projecting seasonal runoff extremes. The aim of the fourth project is to quantify and compare the uncertainties regarding global climate models to the ones from the hydrologic model structures in climate change impact studies. Various methods have been proposed to downscale the coarse resolution General Circulation Model (GCM) climatological variables to the fine scale regional variables; however fewer studies have been focused on the selection of GCM predictors. Additionally, the results obtained from one downscaling technique may not be robust and the uncertainties related to the downscaling scheme are not realized. To address these issues, in the fifth study we employed Independent Component Analysis (ICA) for predictor selection which determines spatially independent GCM variables (as discussed in Appendix A). Cross validation of the independent components is employed to find the predictor combination that describes the regional precipitation over the upper Willamette basin with minimum error. These climate variables along with the observed precipitation are used to calibrate three downscaling models: Multi Linear Regression (MLR), Support Vector Machine (SVM) and Adaptive-Network-Based Fuzzy Inference System (ANFIS). Close

• 32. [Article] Vegetation, Environmental Characteristics, and their Relationships: Variation within the Annually Flooded Riparian Zones of the John Day River Basin, Oregon

  I hypothesized that vegetation and physical environmental characteristics would differ between the upper and lower extents of the annually flooded riparian zone on the John Day River, and that relationships ...

  Citation × Citation Citation Abstract Copy Title: Vegetation, Environmental Characteristics, and their Relationships: Variation within the Annually Flooded Riparian Zones of the John Day River Basin, Oregon Author: Hartsfield, Samuel J. Year: 2009 I hypothesized that vegetation and physical environmental characteristics would differ between the upper and lower extents of the annually flooded riparian zone on the John Day River, and that relationships between species and environmental variables would display differences between these two zones. Vegetation, environmental variables, and relationships between them were assessed for the entire annually flooded riparian zone, and for the proposed upper and lower zones. Data were collected from 60 one-square-meter quadrats: 30 in each the upper and lower zones. Sites were randomly selected and located so that flood duration was roughly equal at all sites within each zone. 34 plant species were encountered: 25 in the upper zone, 27 in the lower zone. Wetland obligate and facultative wetland species groups and eight individual species accounted for statistically different percentages ofquadrat cover between zones. ANOSIM analysis identified two statistically distinct vegetation communities between the two zones. Soil texture averaged 75.85% sand and 20.81% fines. Sand ranged between 36.69% and 95.55%. Fines ranged between 2.54% and 58.84%. A horizon depths and fine soil particle concentrations were greater in the upper zone. Coarser soils with more sand and gravel dominated the lower zone. All enviromnental variables studied, except pH, were highly variable throughout the study area. ANOSIM analysis results suggest that the upper and lower zones have distinct, statistically different physical environments from each other. Regression analyses relating species quadrat cover to physical environmental variables were performed for the total, upper, and lower riparian zones. Numerous differences were identified between the upper and lower riparian zones that the riparian scale analyses did not represent accurately. There were ten instances in which the zone scale analyses identified a relationship in either the upper or lower zone, while the corresponding riparian scale analysis failed to identify any relationship. The results of this study indicate that vegetation and the physical environment are statistically different between the upper and lower zones on this river, and that relationships between a given plant species and environmental variable can vary between zones. Future research and management efforts should consider and address the potential for such between-zone variation. Title: Vegetation, Environmental Characteristics, and their Relationships: Variation within the Annually Flooded Riparian Zones of the John Day River Basin, Oregon Author: Hartsfield, Samuel J. Year: 2009 I hypothesized that vegetation and physical environmental characteristics would differ between the upper and lower extents of the annually flooded riparian zone on the John Day River, and that relationships between species and environmental variables would display differences between these two zones. Vegetation, environmental variables, and relationships between them were assessed for the entire annually flooded riparian zone, and for the proposed upper and lower zones. Data were collected from 60 one-square-meter quadrats: 30 in each the upper and lower zones. Sites were randomly selected and located so that flood duration was roughly equal at all sites within each zone. 34 plant species were encountered: 25 in the upper zone, 27 in the lower zone. Wetland obligate and facultative wetland species groups and eight individual species accounted for statistically different percentages ofquadrat cover between zones. ANOSIM analysis identified two statistically distinct vegetation communities between the two zones. Soil texture averaged 75.85% sand and 20.81% fines. Sand ranged between 36.69% and 95.55%. Fines ranged between 2.54% and 58.84%. A horizon depths and fine soil particle concentrations were greater in the upper zone. Coarser soils with more sand and gravel dominated the lower zone. All enviromnental variables studied, except pH, were highly variable throughout the study area. ANOSIM analysis results suggest that the upper and lower zones have distinct, statistically different physical environments from each other. Regression analyses relating species quadrat cover to physical environmental variables were performed for the total, upper, and lower riparian zones. Numerous differences were identified between the upper and lower riparian zones that the riparian scale analyses did not represent accurately. There were ten instances in which the zone scale analyses identified a relationship in either the upper or lower zone, while the corresponding riparian scale analysis failed to identify any relationship. The results of this study indicate that vegetation and the physical environment are statistically different between the upper and lower zones on this river, and that relationships between a given plant species and environmental variable can vary between zones. Future research and management efforts should consider and address the potential for such between-zone variation. Close

• 33. [Article] Application of Numerical Modeling to Study River Dynamics: Hydro-Geomorphological Evolution Due to Extreme Events in the Sandy River, Oregon

  The Sandy River (OR) is a costal tributary of the Columbia River and has a steep hydroshed 1316 square kilometers which is located on the western side of Mount Hood (elevation range 3 m to 1800 m). The ...

  Citation × Citation Citation Abstract Copy Title: Application of Numerical Modeling to Study River Dynamics: Hydro-Geomorphological Evolution Due to Extreme Events in the Sandy River, Oregon Author: Muhammad, Sarkawt Hamarahim Year: 2017 The Sandy River (OR) is a costal tributary of the Columbia River and has a steep hydroshed 1316 square kilometers which is located on the western side of Mount Hood (elevation range 3 m to 1800 m). The system exhibits highly variable flow: Its average discharge is ~40 m3/s, and the highest recorded discharge was 1739 m3/s in 1964. In this study I model the geomorphic sensitivity of an 1800m reach located the downstream of the former Marmot Dam, which was removed in 2007. The hydro-geomorphic response to major flood has implications for system management and aquatic life. Studying hydro-geomorphic change requires a systematic approach. Here, I define flows and flood hydrographs for specified return interval based on the observed hydrologic record, and then examine potential hydro-geomorphic changes using a numerical model. A Pearson Type III distribution is used to calculate 100, 75, 50, 25, 10, and 2 year return periods. Extreme event hydrographs are derived by fitting derived and observed flood hydrographs to the gamma distribution curve. Sediment transport and geomorphology are then modeled numerically with Nays2DH, a solver that is part of iRIC software. Because the model is computationally intensive, I model the domain with five different spatial grid resolutions, to find proper grid resolution. The grid resolutions used are 1.5 m, 2 m, 3 m, 4 m, and 5 m. We choose 4 m as optimum grid resolution, based on the convergence of model results. The model is run for extreme event hydrographs with six above return periods. For result visualization and analysis, we focus on flow properties and bed elevation at peak flow and at the end of each event. For both times for each event, important flow and sediment transport parameters are visualized for the entire domain in plane form and eight cross-sections at 200 m intervals. Finally, we divide the geomorphic response into areas of erosion and deposition. Linear regression analyses of mean values of erosion and deposition at peak flow for all extreme events yield R2 of 0.981 for erosion and 0.986 for deposition. The mean erosion and deposition depth at the end of the events is modeled by nonlinear regression with correlation coefficient of 0.965 for erosion and 0.998 for deposition. The regression models provide direct understanding of impacts of different floods on the geomorphic response of the river domain. examination of the model as a whole suggest that the amount of erosion and deposition in the bed and banks is a function of channel geometry, bank and bed geology, riparian area condition and strongly depend on the amount of flow through the channel. Title: Application of Numerical Modeling to Study River Dynamics: Hydro-Geomorphological Evolution Due to Extreme Events in the Sandy River, Oregon Author: Muhammad, Sarkawt Hamarahim Year: 2017 The Sandy River (OR) is a costal tributary of the Columbia River and has a steep hydroshed 1316 square kilometers which is located on the western side of Mount Hood (elevation range 3 m to 1800 m). The system exhibits highly variable flow: Its average discharge is ~40 m3/s, and the highest recorded discharge was 1739 m3/s in 1964. In this study I model the geomorphic sensitivity of an 1800m reach located the downstream of the former Marmot Dam, which was removed in 2007. The hydro-geomorphic response to major flood has implications for system management and aquatic life. Studying hydro-geomorphic change requires a systematic approach. Here, I define flows and flood hydrographs for specified return interval based on the observed hydrologic record, and then examine potential hydro-geomorphic changes using a numerical model. A Pearson Type III distribution is used to calculate 100, 75, 50, 25, 10, and 2 year return periods. Extreme event hydrographs are derived by fitting derived and observed flood hydrographs to the gamma distribution curve. Sediment transport and geomorphology are then modeled numerically with Nays2DH, a solver that is part of iRIC software. Because the model is computationally intensive, I model the domain with five different spatial grid resolutions, to find proper grid resolution. The grid resolutions used are 1.5 m, 2 m, 3 m, 4 m, and 5 m. We choose 4 m as optimum grid resolution, based on the convergence of model results. The model is run for extreme event hydrographs with six above return periods. For result visualization and analysis, we focus on flow properties and bed elevation at peak flow and at the end of each event. For both times for each event, important flow and sediment transport parameters are visualized for the entire domain in plane form and eight cross-sections at 200 m intervals. Finally, we divide the geomorphic response into areas of erosion and deposition. Linear regression analyses of mean values of erosion and deposition at peak flow for all extreme events yield R2 of 0.981 for erosion and 0.986 for deposition. The mean erosion and deposition depth at the end of the events is modeled by nonlinear regression with correlation coefficient of 0.965 for erosion and 0.998 for deposition. The regression models provide direct understanding of impacts of different floods on the geomorphic response of the river domain. examination of the model as a whole suggest that the amount of erosion and deposition in the bed and banks is a function of channel geometry, bank and bed geology, riparian area condition and strongly depend on the amount of flow through the channel. Close

• 34. [Article] Portland State Perspective; June 1979

  A quarterly alumni newsletter. In this issue: master plan charts PSU's future; women engineers; anniversary of Vanport flood noted.

  Citation × Citation Citation Abstract Copy Title: Portland State Perspective; June 1979 Author: Portland State University Year: 1979 A quarterly alumni newsletter. In this issue: master plan charts PSU's future; women engineers; anniversary of Vanport flood noted. Title: Portland State Perspective; June 1979 Author: Portland State University Year: 1979 A quarterly alumni newsletter. In this issue: master plan charts PSU's future; women engineers; anniversary of Vanport flood noted. Close

• 35. [Article] Detecting Change in Rainstorm Properties from 1977-2016 and Associated Future Flood Risks in Portland, Oregon

  In response to increased greenhouse gases and global temperatures, changes to the hydrologic cycle are projected to occur and new precipitation characteristics are expected to emerge. The study of these ...

  Citation × Citation Citation Abstract Copy Title: Detecting Change in Rainstorm Properties from 1977-2016 and Associated Future Flood Risks in Portland, Oregon Author: Cooley, Alexis Kirsten Year: 2017 In response to increased greenhouse gases and global temperatures, changes to the hydrologic cycle are projected to occur and new precipitation characteristics are expected to emerge. The study of these characteristics is facilitated by common indices to measure precipitation and temperature developed by the Expert Team on Climate Change Detection and Indices (ETCCDI). These indices can be used to describe the likely consequences of climate change such as increased daily precipitation intensity (SDII) and heavier rainfall events (R95p). This study calculates a subset of these indices from observed and modelled precipitation data in Portland, Oregon. Five rainfall gages from a high resolution rain gage network and projections from three downscaled global climate models including CanESM2, CESM1, CNRM-CM5 are used to calculate precipitation indices. Mann-Kendall's tau is used to detect monotonic trends in indices. The observational record is compared with models for the historic period (1977-2005) and these past trends are compared with projected future trends (2006-2100). The influence of study unit on trend detection is analyzed by computing trends at the annual and monthly scale. Study unit is show to be important for trend detection. When the annual study unit is used, projected future trends towards increased precipitation intensity and event volumes are not observed in the historic data. However, when analyzed with a monthly study unit, trends towards increased precipitation intensity and event volumes are observed in the historic data. These trends are shown to be important for Portland area flooding, as precipitation indices are shown to significantly correlate with 40 maximum peak flow events that occurred during the period of study. Title: Detecting Change in Rainstorm Properties from 1977-2016 and Associated Future Flood Risks in Portland, Oregon Author: Cooley, Alexis Kirsten Year: 2017 In response to increased greenhouse gases and global temperatures, changes to the hydrologic cycle are projected to occur and new precipitation characteristics are expected to emerge. The study of these characteristics is facilitated by common indices to measure precipitation and temperature developed by the Expert Team on Climate Change Detection and Indices (ETCCDI). These indices can be used to describe the likely consequences of climate change such as increased daily precipitation intensity (SDII) and heavier rainfall events (R95p). This study calculates a subset of these indices from observed and modelled precipitation data in Portland, Oregon. Five rainfall gages from a high resolution rain gage network and projections from three downscaled global climate models including CanESM2, CESM1, CNRM-CM5 are used to calculate precipitation indices. Mann-Kendall's tau is used to detect monotonic trends in indices. The observational record is compared with models for the historic period (1977-2005) and these past trends are compared with projected future trends (2006-2100). The influence of study unit on trend detection is analyzed by computing trends at the annual and monthly scale. Study unit is show to be important for trend detection. When the annual study unit is used, projected future trends towards increased precipitation intensity and event volumes are not observed in the historic data. However, when analyzed with a monthly study unit, trends towards increased precipitation intensity and event volumes are observed in the historic data. These trends are shown to be important for Portland area flooding, as precipitation indices are shown to significantly correlate with 40 maximum peak flow events that occurred during the period of study. Close

• 36. [Article] Delivering Green Streets: an Exploration of Changing Perceptions and Behaviours Over Time Around Bioswales in Portland, Oregon

  Green Infrastructure (GI) is an increasingly popular means of dealing with flooding and water quality issues worldwide. This study examines public perceptions of, and behaviour around, bioswales, which ...

  Citation × Citation Citation Abstract Copy Title: Delivering Green Streets: an Exploration of Changing Perceptions and Behaviours Over Time Around Bioswales in Portland, Oregon Author: Everett, Glyn, Lamond, Jessica, Morzillo, Anita T., Matsler, Annie Marissa, Chan, Faith Ka Shun Year: 2015 Green Infrastructure (GI) is an increasingly popular means of dealing with flooding and water quality issues worldwide. This study examines public perceptions of, and behaviour around, bioswales, which are a popular GI facility in the United States. Bioswales are highly visible interventions requiring support from residents and policy-makers to be implemented and maintained appropriately. To understand how the residents’ perceptions and attitudes might develop over time, we interviewed residents of Portland, Oregon, living near bioswales installed 1–2, 4–5 and 8–9 years ago, to determine awareness, understanding, and opinions about the devices. We found no consistent patterns across time periods, but did find common issues affecting residents’ appreciation and acceptance: environmental attitudes, awareness and understanding of purpose and function, plant choice and maintenance, and mess and littering. It was apparent that increased public engagement, localised maintenance strategies, and possibly even customising facilities to meet residents’ needs where feasible, might improve acceptance. Title: Delivering Green Streets: an Exploration of Changing Perceptions and Behaviours Over Time Around Bioswales in Portland, Oregon Author: Everett, Glyn, Lamond, Jessica, Morzillo, Anita T., Matsler, Annie Marissa, Chan, Faith Ka Shun Year: 2015 Green Infrastructure (GI) is an increasingly popular means of dealing with flooding and water quality issues worldwide. This study examines public perceptions of, and behaviour around, bioswales, which are a popular GI facility in the United States. Bioswales are highly visible interventions requiring support from residents and policy-makers to be implemented and maintained appropriately. To understand how the residents’ perceptions and attitudes might develop over time, we interviewed residents of Portland, Oregon, living near bioswales installed 1–2, 4–5 and 8–9 years ago, to determine awareness, understanding, and opinions about the devices. We found no consistent patterns across time periods, but did find common issues affecting residents’ appreciation and acceptance: environmental attitudes, awareness and understanding of purpose and function, plant choice and maintenance, and mess and littering. It was apparent that increased public engagement, localised maintenance strategies, and possibly even customising facilities to meet residents’ needs where feasible, might improve acceptance. Close

• 37. [Article] Production, Oxidation, and Emissions of Methane from Rice Fields in China

  Detailed field studies of methane emissions from rice fields show that when nitrogen fertilizers are used with intermittent irrigation the seasonal average flux is about 3 mg/m²/hr. When continuous flooding ...

  Citation × Citation Citation Abstract Copy Title: Production, Oxidation, and Emissions of Methane from Rice Fields in China Author: Khalil, M. A. K., Shearer, Martha J., Rasmussen, R. A., Duan, Chang-Lin, Ren, Lixin Year: 2008 Detailed field studies of methane emissions from rice fields show that when nitrogen fertilizers are used with intermittent irrigation the seasonal average flux is about 3 mg/m²/hr. When continuous flooding and organic material is added to the same fields, the emissions rise to nearly 30 mg/m²/hr. Production rates measured during the two years when both organic material and water were applied to these fields were found to be 60 and 90 mg/m²/hr in consecutive years. The fraction oxidized is calculated to be about 80% one year and 43% the next year. The results suggest that high organic fertilizer increases production, but may affect the emissions more by reducing oxidation. The data show that seasonally averaged emissions vary by up to factor of 2 among adjacent fields but the variability of production is only about 20%. Information obtained from the farmers suggests that there is a trend towards less use of organic manure as nitrogen fertilizers have become available and the occurrence of intermittent flooding has increased for various reasons. These conditions have likely led to decreasing emissions of methane from rice fields in China in the recent decades. Title: Production, Oxidation, and Emissions of Methane from Rice Fields in China Author: Khalil, M. A. K., Shearer, Martha J., Rasmussen, R. A., Duan, Chang-Lin, Ren, Lixin Year: 2008 Detailed field studies of methane emissions from rice fields show that when nitrogen fertilizers are used with intermittent irrigation the seasonal average flux is about 3 mg/m²/hr. When continuous flooding and organic material is added to the same fields, the emissions rise to nearly 30 mg/m²/hr. Production rates measured during the two years when both organic material and water were applied to these fields were found to be 60 and 90 mg/m²/hr in consecutive years. The fraction oxidized is calculated to be about 80% one year and 43% the next year. The results suggest that high organic fertilizer increases production, but may affect the emissions more by reducing oxidation. The data show that seasonally averaged emissions vary by up to factor of 2 among adjacent fields but the variability of production is only about 20%. Information obtained from the farmers suggests that there is a trend towards less use of organic manure as nitrogen fertilizers have become available and the occurrence of intermittent flooding has increased for various reasons. These conditions have likely led to decreasing emissions of methane from rice fields in China in the recent decades. Close

• 38. [Article] Predictive Time Series Analysis Linking Bengal Cholera with Terrestrial Water Storage Measured from Gravity Recovery and Climate Experiment Sensors

  Outbreaks of diarrheal diseases, including cholera, are related to floods and droughts in regions where water and sanitation infrastructure are inadequate or insufficient. However, availability of data ...

  Citation × Citation Citation Abstract Copy Title: Predictive Time Series Analysis Linking Bengal Cholera with Terrestrial Water Storage Measured from Gravity Recovery and Climate Experiment Sensors Author: Jutla, Antarpreet, Akanda, Ali, Unnikrishnan, Avinash, Huq, Anwar, Colwell, Rita Year: 2015 Outbreaks of diarrheal diseases, including cholera, are related to floods and droughts in regions where water and sanitation infrastructure are inadequate or insufficient. However, availability of data on water scarcity and abundance in transnational basins, are a prerequisite for developing cholera forecasting systems. With more than a decade of terrestrial water storage (TWS) data from the Gravity Recovery and Climate Experiment, conditions favorable for predicting cholera occurrence may now be determined. We explored lead–lag relationships between TWS in the Ganges–Brahmaputra–Meghna basin and endemic cholera in Bangladesh. Since bimodal seasonal peaks in cholera in Bangladesh occur during spring and autumn seasons, two separate logistical models between TWS and disease time series (2002–2010) were developed. TWS representing water availability showed an asymmetrical, strong association with cholera prevalence in the spring (τ = −0.53; P < 0.001) and autumn (τ = 0.45; P < 0.001) up to 6 months in advance. One unit (centimeter of water) decrease in water availability in the basin increased odds of above normal cholera by 24% (confidence interval [CI] = 20–31%; P < 0.05) in the spring, while an increase in regional water by 1 unit, through floods, increased odds of above average cholera in the autumn by 29% (CI = 22–33%; P < 0.05). Title: Predictive Time Series Analysis Linking Bengal Cholera with Terrestrial Water Storage Measured from Gravity Recovery and Climate Experiment Sensors Author: Jutla, Antarpreet, Akanda, Ali, Unnikrishnan, Avinash, Huq, Anwar, Colwell, Rita Year: 2015 Outbreaks of diarrheal diseases, including cholera, are related to floods and droughts in regions where water and sanitation infrastructure are inadequate or insufficient. However, availability of data on water scarcity and abundance in transnational basins, are a prerequisite for developing cholera forecasting systems. With more than a decade of terrestrial water storage (TWS) data from the Gravity Recovery and Climate Experiment, conditions favorable for predicting cholera occurrence may now be determined. We explored lead–lag relationships between TWS in the Ganges–Brahmaputra–Meghna basin and endemic cholera in Bangladesh. Since bimodal seasonal peaks in cholera in Bangladesh occur during spring and autumn seasons, two separate logistical models between TWS and disease time series (2002–2010) were developed. TWS representing water availability showed an asymmetrical, strong association with cholera prevalence in the spring (τ = −0.53; P < 0.001) and autumn (τ = 0.45; P < 0.001) up to 6 months in advance. One unit (centimeter of water) decrease in water availability in the basin increased odds of above normal cholera by 24% (confidence interval [CI] = 20–31%; P < 0.05) in the spring, while an increase in regional water by 1 unit, through floods, increased odds of above average cholera in the autumn by 29% (CI = 22–33%; P < 0.05). Close

• 39. [Article] Integrated hydrologic and hydrochemical observations of Hidden Creek Lake jökulhlaups, Kennicott Glacier, Alaska

  Hidden Creek Lake (HCL), an ice-marginal lake impounded by Kennicott Glacier, Wrangell Mountains, Alaska, fills annually to ~20 to 30 x ~10⁶ m³ and then drains subglacially within 2 to 3 days. During the ...

  Citation × Citation Citation Abstract Copy Title: Integrated hydrologic and hydrochemical observations of Hidden Creek Lake jökulhlaups, Kennicott Glacier, Alaska Author: Anderson, Suzanne P., Walder, Joseph S., Anderson, Robert S., Kraal, Erin R., Cunico, Michelle, Fountain, Andrew G., Trabant, Dennis C. Year: 2003 Hidden Creek Lake (HCL), an ice-marginal lake impounded by Kennicott Glacier, Wrangell Mountains, Alaska, fills annually to ~20 to 30 x ~10⁶ m³ and then drains subglacially within 2 to 3 days. During the 1999 and 2000 jökulhlaups, we carried out a series of planned observations around the lake and in the Kennicott River, which drains the glacier. Approximately 20% of the lake volume was contained within a subglacial water ‘‘wedge’’ beneath the ice dam. The entire volume of the lake drains through the wedge; hydraulic head loss through this constriction may be responsible for the fairly symmetrical shape of the HCL outflow hydrographs, deduced from lake level records, basin hypsometry, and collapse of the ice dam. The flood hydrographs in the Kennicott River are similar in shape to the outflow hydrographs, and within error, lake volume matched the river flood volume in both years. Up to 12 x 10⁶ m³ of water was temporarily stored within the glacier during the 2000 jökulhlaup. During the 2000 jökulhlaup the background flow in the Kennicott River shifted to a dilute chemical composition. As the HCL jökulhlaup progressed, Donoho Falls Lake filled with water whose chemistry was closer to that of the background flow in Kennicott River than to HCL water. Comparison of these chemical signals with typical summer variations in Kennicott River chemistry suggests that the jökulhlaup created high subglacial water pressure that impeded normal drainage of solute-rich water from a distributed drainage system into a conduit system at the glacier bed and even caused flow direction locally to reverse. Title: Integrated hydrologic and hydrochemical observations of Hidden Creek Lake jökulhlaups, Kennicott Glacier, Alaska Author: Anderson, Suzanne P., Walder, Joseph S., Anderson, Robert S., Kraal, Erin R., Cunico, Michelle, Fountain, Andrew G., Trabant, Dennis C. Year: 2003 Hidden Creek Lake (HCL), an ice-marginal lake impounded by Kennicott Glacier, Wrangell Mountains, Alaska, fills annually to ~20 to 30 x ~10⁶ m³ and then drains subglacially within 2 to 3 days. During the 1999 and 2000 jökulhlaups, we carried out a series of planned observations around the lake and in the Kennicott River, which drains the glacier. Approximately 20% of the lake volume was contained within a subglacial water ‘‘wedge’’ beneath the ice dam. The entire volume of the lake drains through the wedge; hydraulic head loss through this constriction may be responsible for the fairly symmetrical shape of the HCL outflow hydrographs, deduced from lake level records, basin hypsometry, and collapse of the ice dam. The flood hydrographs in the Kennicott River are similar in shape to the outflow hydrographs, and within error, lake volume matched the river flood volume in both years. Up to 12 x 10⁶ m³ of water was temporarily stored within the glacier during the 2000 jökulhlaup. During the 2000 jökulhlaup the background flow in the Kennicott River shifted to a dilute chemical composition. As the HCL jökulhlaup progressed, Donoho Falls Lake filled with water whose chemistry was closer to that of the background flow in Kennicott River than to HCL water. Comparison of these chemical signals with typical summer variations in Kennicott River chemistry suggests that the jökulhlaup created high subglacial water pressure that impeded normal drainage of solute-rich water from a distributed drainage system into a conduit system at the glacier bed and even caused flow direction locally to reverse. Close

• 40. [Article] Greenhouse Gas Fluxes in Southeastern U.S. Coastal Plain Wetlands Under Contrasting Land Uses

  Whether through sea level rise or wetland restoration, agricultural soils in coastal areas will be inundated at increasing rates, renewing connections to sensitive surface waters and raising critical questions ...

  Citation × Citation Citation Abstract Copy Title: Greenhouse Gas Fluxes in Southeastern U.S. Coastal Plain Wetlands Under Contrasting Land Uses Author: Morse, Jennifer L., Ardón, Marcelo, Bernhardt, Emily S. Year: 2012 Whether through sea level rise or wetland restoration, agricultural soils in coastal areas will be inundated at increasing rates, renewing connections to sensitive surface waters and raising critical questions about environmental trade-offs. Wetland restoration is often implemented in agricultural catchments to improve water quality through nutrient removal. Yet flooding of soils can also increase production of the greenhouse gases nitrous oxide and methane, representing a potential environmental trade-off. Our study aimed to quantify and compare greenhouse gas emissions from unmanaged and restored forested wetlands, as well as actively managed agricultural fields within the North Carolina coastal plain, USA. In sampling conducted once every two months over a two-year comparative study, we found that soil carbon dioxide flux (range: 8000–64 800 kg CO2·ha-1· yr-1) comprised 66–100% of total greenhouse gas emissions from all sites and that methane emissions (range: -6.87 to 197 kg CH4·ha-1·yr-1) were highest from permanently inundated sites, while nitrous oxide fluxes (range: -1.07 to 139 kg N2O·ha-1·yr-1) were highest in sites with lower water tables. Contrary to predictions, greenhouse gas fluxes (as CO2 equivalents) from the restored wetland were lower than from either agricultural fields or unmanaged forested wetlands. In these acidic coastal freshwater ecosystems, the conversion of agricultural fields to flooded young forested wetlands did not result in increases in greenhouse gas emissions. Title: Greenhouse Gas Fluxes in Southeastern U.S. Coastal Plain Wetlands Under Contrasting Land Uses Author: Morse, Jennifer L., Ardón, Marcelo, Bernhardt, Emily S. Year: 2012 Whether through sea level rise or wetland restoration, agricultural soils in coastal areas will be inundated at increasing rates, renewing connections to sensitive surface waters and raising critical questions about environmental trade-offs. Wetland restoration is often implemented in agricultural catchments to improve water quality through nutrient removal. Yet flooding of soils can also increase production of the greenhouse gases nitrous oxide and methane, representing a potential environmental trade-off. Our study aimed to quantify and compare greenhouse gas emissions from unmanaged and restored forested wetlands, as well as actively managed agricultural fields within the North Carolina coastal plain, USA. In sampling conducted once every two months over a two-year comparative study, we found that soil carbon dioxide flux (range: 8000–64 800 kg CO2·ha-1· yr-1) comprised 66–100% of total greenhouse gas emissions from all sites and that methane emissions (range: -6.87 to 197 kg CH4·ha-1·yr-1) were highest from permanently inundated sites, while nitrous oxide fluxes (range: -1.07 to 139 kg N2O·ha-1·yr-1) were highest in sites with lower water tables. Contrary to predictions, greenhouse gas fluxes (as CO2 equivalents) from the restored wetland were lower than from either agricultural fields or unmanaged forested wetlands. In these acidic coastal freshwater ecosystems, the conversion of agricultural fields to flooded young forested wetlands did not result in increases in greenhouse gas emissions. Close

• 41. [Article] Migration Movement

  All†Borders†Are†Temporary "Migration is a phenomenon, not a problem – something that simply is. The right to migrate and to move freely is our human right. When societies restrict or choke off the movements ...

  Citation × Citation Citation Abstract Copy Title: Migration Movement Author: Porte, Robert Year: 2016 All†Borders†Are†Temporary "Migration is a phenomenon, not a problem – something that simply is. The right to migrate and to move freely is our human right. When societies restrict or choke off the movements of their citizens, they end up doing the work of a dam, they generate power and control floods, but in doing so they destroy life and wreck the surrounding space." Justseeds†(excerpt) As the current administration at the time of this writing continues its program of deportation of women and children from the U.S. to their war torn and violent countries of origin, I want not to engage in an art practice that doesn’t consider the sociopolitical climate of our times. Title: Migration Movement Author: Porte, Robert Year: 2016 All†Borders†Are†Temporary "Migration is a phenomenon, not a problem – something that simply is. The right to migrate and to move freely is our human right. When societies restrict or choke off the movements of their citizens, they end up doing the work of a dam, they generate power and control floods, but in doing so they destroy life and wreck the surrounding space." Justseeds†(excerpt) As the current administration at the time of this writing continues its program of deportation of women and children from the U.S. to their war torn and violent countries of origin, I want not to engage in an art practice that doesn’t consider the sociopolitical climate of our times. Close

• 42. [Article] Cleaner Drain

  Water in streets causes several issues, both to our infrastructure and our emotions. The water can harm property by rotting wooden structures. If the water is high enough, it can even stall cars and flood ...

  Citation × Citation Citation Abstract Copy Title: Cleaner Drain Author: Paivarinta, Jonah, Ortiz‐Rojo, Daniel, Klepp, Masson, Likestoskat, Rebekah, Chadney, Macy, Ferrando, Jeremy Year: 2015 Water in streets causes several issues, both to our infrastructure and our emotions. The water can harm property by rotting wooden structures. If the water is high enough, it can even stall cars and flood into buildings. Being forced to walk through or around a puddle can hurt someone's emotional state, which reduces productivity and this affect people around them. It costs about 30 dollars to clean a drain, and there are about 15 thousand drains, which totals to to around$450,000 and if you add in other costs such as employees and street sweeping for a cleaning company it costs around 3.8 million a year. Title: Cleaner Drain Author: Paivarinta, Jonah, Ortiz‐Rojo, Daniel, Klepp, Masson, Likestoskat, Rebekah, Chadney, Macy, Ferrando, Jeremy Year: 2015 Water in streets causes several issues, both to our infrastructure and our emotions. The water can harm property by rotting wooden structures. If the water is high enough, it can even stall cars and flood into buildings. Being forced to walk through or around a puddle can hurt someone's emotional state, which reduces productivity and this affect people around them. It costs about 30 dollars to clean a drain, and there are about 15 thousand drains, which totals to to around$450,000 and if you add in other costs such as employees and street sweeping for a cleaning company it costs around 3.8 million a year. Close

• 43. [Article] Structure and influence of the Tillamook Uplift on the stratigraphy of the Mist area, Oregon

  Fifty three sedimentary samples were analyzed for their minor and trace element concentrations utilizing instrumental neutron activation analysis. Concentrations of Na, K, La, Sm and Sc, and their ratios ...

  Citation × Citation Citation Abstract Copy Title: Structure and influence of the Tillamook Uplift on the stratigraphy of the Mist area, Oregon Author: Kadri, Moinoddin Murtuzamiya Year: 1982 Fifty three sedimentary samples were analyzed for their minor and trace element concentrations utilizing instrumental neutron activation analysis. Concentrations of Na, K, La, Sm and Sc, and their ratios appear to establish significant trends. The data suggest a major break from a granitic-metamorphic provenance and a volcanic component dominated provenance between the Cowlitz and Keasey Formations respectively. The provenance of the Astoria Formation indicates the presence of flood basalts. Title: Structure and influence of the Tillamook Uplift on the stratigraphy of the Mist area, Oregon Author: Kadri, Moinoddin Murtuzamiya Year: 1982 Fifty three sedimentary samples were analyzed for their minor and trace element concentrations utilizing instrumental neutron activation analysis. Concentrations of Na, K, La, Sm and Sc, and their ratios appear to establish significant trends. The data suggest a major break from a granitic-metamorphic provenance and a volcanic component dominated provenance between the Cowlitz and Keasey Formations respectively. The provenance of the Astoria Formation indicates the presence of flood basalts. Close

• 44. [Article] Periodic Atlas of the Metroscape: Natural Hazards: Are You at Risk

  This edition of the Periodic Atlas of the Metroscape focuses on hazard analysis, and looks at the relative danger of earthquake, flood, landslide, debris flow, lava flow, and radon throughout the Portland ...

  Citation × Citation Citation Abstract Copy Title: Periodic Atlas of the Metroscape: Natural Hazards: Are You at Risk Author: Sanchez, Tom, Burns, Scott, Dorwart, Jon, Merrick, Meg Year: 2002 This edition of the Periodic Atlas of the Metroscape focuses on hazard analysis, and looks at the relative danger of earthquake, flood, landslide, debris flow, lava flow, and radon throughout the Portland area. The maps are printed in 3D format, and the print edition of the Metroscape included special glasses that, when worn, give the maps a 3D appearance. Title: Periodic Atlas of the Metroscape: Natural Hazards: Are You at Risk Author: Sanchez, Tom, Burns, Scott, Dorwart, Jon, Merrick, Meg Year: 2002 This edition of the Periodic Atlas of the Metroscape focuses on hazard analysis, and looks at the relative danger of earthquake, flood, landslide, debris flow, lava flow, and radon throughout the Portland area. The maps are printed in 3D format, and the print edition of the Metroscape included special glasses that, when worn, give the maps a 3D appearance. Close

• 45. [Article] The Columbia River's fate in the twentieth century

  Discusses the history of the Columbia River during the 20th century, emphasizing the image of the river as both a source of industry and an example of wild natural beauty. In 1933 the river was dammed ...

  Citation × Citation Citation Abstract Copy Title: The Columbia River's fate in the twentieth century Author: Lang, William L. Year: 2000 Discusses the history of the Columbia River during the 20th century, emphasizing the image of the river as both a source of industry and an example of wild natural beauty. In 1933 the river was dammed to harness its power for hydroelectricity and control its unpredictable flooding. With the completion of the dams in the 1970's, however, came problems with the edenic vision of the river, especially with the annual salmon run. By the late 20th century, the salmon had all but disappeared, leading to an ongoing conflict between supporters of the dams and conservationists. Title: The Columbia River's fate in the twentieth century Author: Lang, William L. Year: 2000 Discusses the history of the Columbia River during the 20th century, emphasizing the image of the river as both a source of industry and an example of wild natural beauty. In 1933 the river was dammed to harness its power for hydroelectricity and control its unpredictable flooding. With the completion of the dams in the 1970's, however, came problems with the edenic vision of the river, especially with the annual salmon run. By the late 20th century, the salmon had all but disappeared, leading to an ongoing conflict between supporters of the dams and conservationists. Close

• 46. [Article] Interview with Willie Mae Hart

  Interview with Willie Mae Hart by Heather Burmeister and Lisa Donnelly on February 25, 2010, in Portland, Oregon. Willie discusses the many important moments in Oregon history such as the Vanport Flood, ...

  Citation × Citation Citation Abstract Copy Title: Interview with Willie Mae Hart Author: Donnelly, Lisa Chere', Burmeister, Heather Jo Year: 2010 Interview with Willie Mae Hart by Heather Burmeister and Lisa Donnelly on February 25, 2010, in Portland, Oregon. Willie discusses the many important moments in Oregon history such as the Vanport Flood, the debate over the Public Accommodations Act, and presidential candidate John F. Kennedy's campaign visit to Portland in 1960, where he met Willie Mae at an event that she had organized. Title: Interview with Willie Mae Hart Author: Donnelly, Lisa Chere', Burmeister, Heather Jo Year: 2010 Interview with Willie Mae Hart by Heather Burmeister and Lisa Donnelly on February 25, 2010, in Portland, Oregon. Willie discusses the many important moments in Oregon history such as the Vanport Flood, the debate over the Public Accommodations Act, and presidential candidate John F. Kennedy's campaign visit to Portland in 1960, where he met Willie Mae at an event that she had organized. Close

• 47. [Article] Characterization of the Red Bluff Landslide, Greater Cascade Landslide Complex, Columbia River Gorge, Washington

  Located in the Columbia River Gorge, The Red Bluff Landslide (18.8 km2) is one of four large landslides that make up the Cascade Landslide Complex. In its current form, the Red Bluff Landslide is a post-Missoula ...

  Citation × Citation Citation Abstract Copy Title: Characterization of the Red Bluff Landslide, Greater Cascade Landslide Complex, Columbia River Gorge, Washington Author: Randall, James Robert Year: 2012 Located in the Columbia River Gorge, The Red Bluff Landslide (18.8 km2) is one of four large landslides that make up the Cascade Landslide Complex. In its current form, the Red Bluff Landslide is a post-Missoula Flood feature made up of two components: an active upper lobe (8.6 km2) that is translational, creeping to the south at 25 cm/yr and spreading laterally to the east at 6 cm/yr over a semi-fixed portion (10.2 km2) of the Red Bluff Landslide area that has been "smoothed" by Missoula Floods. The upper active lobe is the landslide debris accumulated since Missoula Flood time (~15,000 yr. BP). Five separate collapse events have been identified and rock failures along the main scarp headwalls continue. Two rock avalanches on the Red Bluff Landslide were mapped. The Old Greenleaf Basin Rock Avalanche is estimated to have occurred 100 to 150 years ago, represents the fifth collapse event on the Red Bluff Landslide, and covers an area of 200,000 m2. It has a volume of 4.2 million m3; its length is 748 m and has a width of 215 m. On January 3, 2008, the Greenleaf Basin Rock Avalanche occurred, flowing over the Old Greenleaf Basin Rock Avalanche, covering an area of 100,000 m2 and deposited a volume of about 375,000 m3. Its length is 730 m with an average depth of 1.22 m. It contributed approximately 0.058% of the total volume and 0.01% of the surface area to the active upper lobe portion of the Red Bluff Landslide. The Greenleaf Basin Rock Avalanche was determined to be insignificant in the movement of the active part of the Red Bluff Landslide during the winter of 2007-2008. The original Cascade Landslide Complex map (Wise, 1961) included the Mosley Lakes Landslide which has now been removed because it lacked the characteristics of a landslide like a scarp. The original complex (35.5 km2) has been renamed the "Greater Cascade Landslide Complex" (43.0 km2), with the addition of the adjacent Stevenson Slide and the elimination of the Mosley Lakes Landslide. Title: Characterization of the Red Bluff Landslide, Greater Cascade Landslide Complex, Columbia River Gorge, Washington Author: Randall, James Robert Year: 2012 Located in the Columbia River Gorge, The Red Bluff Landslide (18.8 km2) is one of four large landslides that make up the Cascade Landslide Complex. In its current form, the Red Bluff Landslide is a post-Missoula Flood feature made up of two components: an active upper lobe (8.6 km2) that is translational, creeping to the south at 25 cm/yr and spreading laterally to the east at 6 cm/yr over a semi-fixed portion (10.2 km2) of the Red Bluff Landslide area that has been "smoothed" by Missoula Floods. The upper active lobe is the landslide debris accumulated since Missoula Flood time (~15,000 yr. BP). Five separate collapse events have been identified and rock failures along the main scarp headwalls continue. Two rock avalanches on the Red Bluff Landslide were mapped. The Old Greenleaf Basin Rock Avalanche is estimated to have occurred 100 to 150 years ago, represents the fifth collapse event on the Red Bluff Landslide, and covers an area of 200,000 m2. It has a volume of 4.2 million m3; its length is 748 m and has a width of 215 m. On January 3, 2008, the Greenleaf Basin Rock Avalanche occurred, flowing over the Old Greenleaf Basin Rock Avalanche, covering an area of 100,000 m2 and deposited a volume of about 375,000 m3. Its length is 730 m with an average depth of 1.22 m. It contributed approximately 0.058% of the total volume and 0.01% of the surface area to the active upper lobe portion of the Red Bluff Landslide. The Greenleaf Basin Rock Avalanche was determined to be insignificant in the movement of the active part of the Red Bluff Landslide during the winter of 2007-2008. The original Cascade Landslide Complex map (Wise, 1961) included the Mosley Lakes Landslide which has now been removed because it lacked the characteristics of a landslide like a scarp. The original complex (35.5 km2) has been renamed the "Greater Cascade Landslide Complex" (43.0 km2), with the addition of the adjacent Stevenson Slide and the elimination of the Mosley Lakes Landslide. Close

• 48. [Article] Long-term Responses of Phalaris arundinacea and Columbia River Bottomland Vegetation to Managed Flooding

  I sought to determine the effect of managed flooding on Phalaris arundinacea L. and other plant species distributions in a large wetland complex, Smith and Bybee Wetlands (SBW), in northwestern Oregon. ...

  Citation × Citation Citation Abstract Copy Title: Long-term Responses of Phalaris arundinacea and Columbia River Bottomland Vegetation to Managed Flooding Author: Farrelly, Tina Schantz Year: 2012 I sought to determine the effect of managed flooding on Phalaris arundinacea L. and other plant species distributions in a large wetland complex, Smith and Bybee Wetlands (SBW), in northwestern Oregon. Altered hydrology has reduced historically high spring flow and prematurely initiated the historic summer drying period at SBW. This alteration has increased the coverage of invasive plants (e.g., P. arundinacea) causing a decrease in native plant cover and thus degrading ecological functions. SBW managers installed a water control structure (WCS) between SBW and the Columbia Slough/River system to impound winter rainfall and thus approximate the ecological benefits that natural flooding provided as well as reduce the abundance of P. arundinacea. Prior researchers conducted intensive vegetation and hydrological monitoring in 2003 (during the season immediately before WCS installation) and 2004. I conducted similar analysis in the fifth and sixth years, 2008 and 2009, following establishment of the WCS. Both study years, I determined percent cover of all vegetation on transects established in 2003. The results, including 2004, as well as 2008 and 2009 showed a reduced cover of P. arundinacea in areas experiencing at least 0.6 meters of inundation and an increased cover of native plant communities when compared to the 2003 baseline data. Native Carex aperta Boott. cover increased 7-fold from 0.3% to 2.3%; Polygonum species cover increased from 20.0% to 52.6%; and Salix lucida Muhl. ssp. lasiandra (Benth.) E. Murray cover increased from 10.9% to 15.5% cover. P. arundinacea declined by over one-third from 44.4% to 28.1% cover following water management. Since hydrology management began, the native Polygonum species community replaced P. arundinacea as the dominant species in the emergent zone. The results of this study refined the suggested depth of inundation needed to reduce P. arundinacea cover in such lake-wetland complexes as SBW from 0.85 meters (based on 2004 study results) to 0.6 meters. Shannon Diversity decreased following water management. The findings of this study demonstrated that water management can enhance native bottomland communities, especially those comprised of obligate wetland species, and reduce P. arundinacea cover in areas experiencing at least 0.6 meters of inundation. Title: Long-term Responses of Phalaris arundinacea and Columbia River Bottomland Vegetation to Managed Flooding Author: Farrelly, Tina Schantz Year: 2012 I sought to determine the effect of managed flooding on Phalaris arundinacea L. and other plant species distributions in a large wetland complex, Smith and Bybee Wetlands (SBW), in northwestern Oregon. Altered hydrology has reduced historically high spring flow and prematurely initiated the historic summer drying period at SBW. This alteration has increased the coverage of invasive plants (e.g., P. arundinacea) causing a decrease in native plant cover and thus degrading ecological functions. SBW managers installed a water control structure (WCS) between SBW and the Columbia Slough/River system to impound winter rainfall and thus approximate the ecological benefits that natural flooding provided as well as reduce the abundance of P. arundinacea. Prior researchers conducted intensive vegetation and hydrological monitoring in 2003 (during the season immediately before WCS installation) and 2004. I conducted similar analysis in the fifth and sixth years, 2008 and 2009, following establishment of the WCS. Both study years, I determined percent cover of all vegetation on transects established in 2003. The results, including 2004, as well as 2008 and 2009 showed a reduced cover of P. arundinacea in areas experiencing at least 0.6 meters of inundation and an increased cover of native plant communities when compared to the 2003 baseline data. Native Carex aperta Boott. cover increased 7-fold from 0.3% to 2.3%; Polygonum species cover increased from 20.0% to 52.6%; and Salix lucida Muhl. ssp. lasiandra (Benth.) E. Murray cover increased from 10.9% to 15.5% cover. P. arundinacea declined by over one-third from 44.4% to 28.1% cover following water management. Since hydrology management began, the native Polygonum species community replaced P. arundinacea as the dominant species in the emergent zone. The results of this study refined the suggested depth of inundation needed to reduce P. arundinacea cover in such lake-wetland complexes as SBW from 0.85 meters (based on 2004 study results) to 0.6 meters. Shannon Diversity decreased following water management. The findings of this study demonstrated that water management can enhance native bottomland communities, especially those comprised of obligate wetland species, and reduce P. arundinacea cover in areas experiencing at least 0.6 meters of inundation. Close

• 49. [Article] Nineteenth Century North American and Pacific Tidal Data: Lost or Just Forgotten?

  Tide data are the oldest and longest oceanographic records and comprise one of the few tools for understanding, quantifying, and separating century-scale human and climate impacts on the coastal zone. ...

  Citation × Citation Citation Abstract Copy Title: Nineteenth Century North American and Pacific Tidal Data: Lost or Just Forgotten? Author: Talke, Stefan A., Jay, David A. Year: 2013 Tide data are the oldest and longest oceanographic records and comprise one of the few tools for understanding, quantifying, and separating century-scale human and climate impacts on the coastal zone. Our archival research indicates that continuous measurements of tides began in 1844 in the western Atlantic, 1853 in the Eastern Pacific, and 1858 in the Western Pacific. At least 50 multiyear tide series existed by the year 1900. With few exceptions, however, these 19th and early 20th century measurements have not been analyzed in more than a century and have been forgotten and neglected by the scientific community. This article describes historical tide measurements in the Pacific Ocean and North America, their current status, and ongoing efforts to recover the data. Possible uses of the data include assessing trends in sea level, tidal properties, and river flow, and reanalyzing extreme events such as historical storms and floods. More than 600 years of station data are confirmed to still exist in paper form, out of approximately 1900 years total. Title: Nineteenth Century North American and Pacific Tidal Data: Lost or Just Forgotten? Author: Talke, Stefan A., Jay, David A. Year: 2013 Tide data are the oldest and longest oceanographic records and comprise one of the few tools for understanding, quantifying, and separating century-scale human and climate impacts on the coastal zone. Our archival research indicates that continuous measurements of tides began in 1844 in the western Atlantic, 1853 in the Eastern Pacific, and 1858 in the Western Pacific. At least 50 multiyear tide series existed by the year 1900. With few exceptions, however, these 19th and early 20th century measurements have not been analyzed in more than a century and have been forgotten and neglected by the scientific community. This article describes historical tide measurements in the Pacific Ocean and North America, their current status, and ongoing efforts to recover the data. Possible uses of the data include assessing trends in sea level, tidal properties, and river flow, and reanalyzing extreme events such as historical storms and floods. More than 600 years of station data are confirmed to still exist in paper form, out of approximately 1900 years total. Close

• 50. [Article] Increasing Storm Tides in New York Harbor, 1844–2013

  Three of the nine highest recorded water levels in the New York Harbor region have occurred since 2010 (March 2010, August 2011, and October 2012), and eight of the largest twenty have occurred since 1990. ...

  Citation × Citation Citation Abstract Copy Title: Increasing Storm Tides in New York Harbor, 1844–2013 Author: Talke, Stefan A., Orton, Philip M., Jay, David A. Year: 2014 Three of the nine highest recorded water levels in the New York Harbor region have occurred since 2010 (March 2010, August 2011, and October 2012), and eight of the largest twenty have occurred since 1990. To investigate whether this cluster of high waters is a random occurrence or indicative of intensified storm tides, we recover archival tide gauge data back to 1844 and evaluate the trajectory of the annual maximum storm tide. Approximately half of long-term variance is anticorrelated with decadal-scale variations in the North Atlantic Oscillation, while long-term trends explain the remainder. The 10 year storm tide has increased by 0.28 m. Combined with a 0.44 m increase in local sea level since 1856, the 10 year flood level has increased by approximately 0.72 ± 0.25 m, and magnified the annual probability of overtopping the typical Manhattan seawall from less than 1% to about 20–25%. Title: Increasing Storm Tides in New York Harbor, 1844–2013 Author: Talke, Stefan A., Orton, Philip M., Jay, David A. Year: 2014 Three of the nine highest recorded water levels in the New York Harbor region have occurred since 2010 (March 2010, August 2011, and October 2012), and eight of the largest twenty have occurred since 1990. To investigate whether this cluster of high waters is a random occurrence or indicative of intensified storm tides, we recover archival tide gauge data back to 1844 and evaluate the trajectory of the annual maximum storm tide. Approximately half of long-term variance is anticorrelated with decadal-scale variations in the North Atlantic Oscillation, while long-term trends explain the remainder. The 10 year storm tide has increased by 0.28 m. Combined with a 0.44 m increase in local sea level since 1856, the 10 year flood level has increased by approximately 0.72 ± 0.25 m, and magnified the annual probability of overtopping the typical Manhattan seawall from less than 1% to about 20–25%. Close

• 51. [Article] Sustainable Drainage Systems: Helping People Live with Water

  Sustainable drainage systems or ‘Suds’ are increasingly accepted as an effective means of ‘making space for water’, adapting to possible climate change and helping communities become more flood and drought ...

  Citation × Citation Citation Abstract Copy Title: Sustainable Drainage Systems: Helping People Live with Water Author: Everett, Glyn, Lamond, Jessica, Morzillo, Anita T., Chan, Faith Ka Shun, Matsler, Annie Marissa Year: 2016 Sustainable drainage systems or ‘Suds’ are increasingly accepted as an effective means of ‘making space for water’, adapting to possible climate change and helping communities become more flood and drought resilient. This study explores potential shifts in perception and attitude through Suds installation, development and habituation. Attitudes and awareness in communities in the USA and UK, where Suds have been in place for some time, were compared and contrasted, examining any evolution of beliefs and practices and wider community resilience. The principal finding was that there existed a lack of understanding about the existence and function of Suds. The paper concludes that consultation regarding solutions during Suds planning and installation, and ongoing dialogue afterwards, could usefully be explored as a means to improve local awareness of and satisfaction with Suds and promote greater understanding of their function. This may in turn encourage behaviour change to improve longer-term functionality... Title: Sustainable Drainage Systems: Helping People Live with Water Author: Everett, Glyn, Lamond, Jessica, Morzillo, Anita T., Chan, Faith Ka Shun, Matsler, Annie Marissa Year: 2016 Sustainable drainage systems or ‘Suds’ are increasingly accepted as an effective means of ‘making space for water’, adapting to possible climate change and helping communities become more flood and drought resilient. This study explores potential shifts in perception and attitude through Suds installation, development and habituation. Attitudes and awareness in communities in the USA and UK, where Suds have been in place for some time, were compared and contrasted, examining any evolution of beliefs and practices and wider community resilience. The principal finding was that there existed a lack of understanding about the existence and function of Suds. The paper concludes that consultation regarding solutions during Suds planning and installation, and ongoing dialogue afterwards, could usefully be explored as a means to improve local awareness of and satisfaction with Suds and promote greater understanding of their function. This may in turn encourage behaviour change to improve longer-term functionality... Close

• 52. [Article] Paleotsunami Inundation of a Beach Ridge Plain: Cobble Ridge Overtopping and Interridge Valley Flooding in Seaside, Oregon, USA

  The Seaside beach ridge plain was inundated by six paleotsunamis during the last ∼2500 years. Large runups (adjusted >10m in height) overtopped seawardmost cobble beach ridges (7m elevation) at ∼1.3 and ...

  Citation × Citation Citation Abstract Copy Title: Paleotsunami Inundation of a Beach Ridge Plain: Cobble Ridge Overtopping and Interridge Valley Flooding in Seaside, Oregon, USA Author: Peterson, Curt D., Jol, Harry M., Horning, Thomas, Cruikshank, Kenneth M. Year: 2010 The Seaside beach ridge plain was inundated by six paleotsunamis during the last ∼2500 years. Large runups (adjusted >10m in height) overtopped seawardmost cobble beach ridges (7m elevation) at ∼1.3 and ∼2.6 ka before present. Smaller paleotsunami (6−8m in height) likely entered the beach plain interior (4-5m elevation) through the paleo-Necanicum bay mouth. The AD 1700 Cascadia paleotsunami had a modest runup (6-7mheight), yet it locally inundated to 1.5 km landward distance. Bed shear stresses (100−3,300 dyne cm−2) are estimated for paleotsunami surges (0.5−2m depths) that flowed down slopes (0.002−0.017 gradient) on the landward side of the cobble beach ridges. Critical entrainment shear stresses of 1,130−1,260 dyne cm−2 were needed to dislodge the largest clasts (26−32 cm diameter) in paleotsunami coulees that were cut (100−200m width) into the landward side of the cobble ridges. Title: Paleotsunami Inundation of a Beach Ridge Plain: Cobble Ridge Overtopping and Interridge Valley Flooding in Seaside, Oregon, USA Author: Peterson, Curt D., Jol, Harry M., Horning, Thomas, Cruikshank, Kenneth M. Year: 2010 The Seaside beach ridge plain was inundated by six paleotsunamis during the last ∼2500 years. Large runups (adjusted >10m in height) overtopped seawardmost cobble beach ridges (7m elevation) at ∼1.3 and ∼2.6 ka before present. Smaller paleotsunami (6−8m in height) likely entered the beach plain interior (4-5m elevation) through the paleo-Necanicum bay mouth. The AD 1700 Cascadia paleotsunami had a modest runup (6-7mheight), yet it locally inundated to 1.5 km landward distance. Bed shear stresses (100−3,300 dyne cm−2) are estimated for paleotsunami surges (0.5−2m depths) that flowed down slopes (0.002−0.017 gradient) on the landward side of the cobble beach ridges. Critical entrainment shear stresses of 1,130−1,260 dyne cm−2 were needed to dislodge the largest clasts (26−32 cm diameter) in paleotsunami coulees that were cut (100−200m width) into the landward side of the cobble ridges. Close

• 53. [Article] Mapping of Groundwater Potential Zones in the Musi Basin Using Remote Sensing Data and GIS

  The objective of this study is to explore the groundwater availability for agriculture in the Musi basin. Remote sensing data and geographic information system were used to locate potential zones for groundwater ...

  Citation × Citation Citation Abstract Copy Title: Mapping of Groundwater Potential Zones in the Musi Basin Using Remote Sensing Data and GIS Author: Ganapuram, Sreedhar, Kumar, G.T. Vijaya, Krishna, I.V. Murali, Kahya, Ercan, Demirel, Mehmet Year: 2009 The objective of this study is to explore the groundwater availability for agriculture in the Musi basin. Remote sensing data and geographic information system were used to locate potential zones for groundwater in the Musi basin. Various maps (i.e., base, hydrogeomorphological, geological, structural, drainage, slope, land use/land cover and groundwater prospect zones) were prepared using the remote sensing data along with the existing maps. The groundwater availability of the basin is qualitatively classified into different classes (i.e., very good, good, moderate, poor and nil) based on its hydrogeomorphological conditions. The land use/land cover map was prepared for the Kharif season using a digital classification technique with the limited ground truth for mapping irrigated areas in the Musi basin. The alluvial plain in filled valley, flood plain and deeply buried pediplain were successfully delineated and shown as the prospective zones of groundwater. Title: Mapping of Groundwater Potential Zones in the Musi Basin Using Remote Sensing Data and GIS Author: Ganapuram, Sreedhar, Kumar, G.T. Vijaya, Krishna, I.V. Murali, Kahya, Ercan, Demirel, Mehmet Year: 2009 The objective of this study is to explore the groundwater availability for agriculture in the Musi basin. Remote sensing data and geographic information system were used to locate potential zones for groundwater in the Musi basin. Various maps (i.e., base, hydrogeomorphological, geological, structural, drainage, slope, land use/land cover and groundwater prospect zones) were prepared using the remote sensing data along with the existing maps. The groundwater availability of the basin is qualitatively classified into different classes (i.e., very good, good, moderate, poor and nil) based on its hydrogeomorphological conditions. The land use/land cover map was prepared for the Kharif season using a digital classification technique with the limited ground truth for mapping irrigated areas in the Musi basin. The alluvial plain in filled valley, flood plain and deeply buried pediplain were successfully delineated and shown as the prospective zones of groundwater. Close

• 54. [Article] Lava and Ice Interaction at Stratovolcanoes: Use of Characteristic Features to Determine Past Glacial Extents and Future Volcanic Hazards

  Structures resulting from lava and ice interaction are common at glaciated stratovolcanoes. During summit eruptions at stratovolcanoes, meltwater is produced and travels freely down steep slopes and thin ...

  Citation × Citation Citation Abstract Copy Title: Lava and Ice Interaction at Stratovolcanoes: Use of Characteristic Features to Determine Past Glacial Extents and Future Volcanic Hazards Author: Lescinsky, David T., Fink, Jonathan H. Year: 2000 Structures resulting from lava and ice interaction are common at glaciated stratovolcanoes. During summit eruptions at stratovolcanoes, meltwater is produced and travels freely down steep slopes and thin permeable valley glaciers, eroding the ice and enlarging preexisting glacial drainages. As a result, in this environment have produced few catastrophic floods. Lava flowing into the open channels and voids in the glaciers becomes confined and grows thicker, filling the available space and producing steep-sided bodies with smooth, bulbous contact surfaces. Quenching of lava against ice or by water forms small-scale features such as tensional fractures and glass. As the amount of meltwater in contact with the lava increases, the type and abundance of smaller-scale features become similar to those produced during subglacial eruptions in meltwater lakes. Identification of large- and small-scale lava-ice contact features in the field can be used to reconstruct paleoglacial extent and, combined with geochronology of lavas, to determine past paleoclimate. An understanding of lava-ice interaction allows us to better access the hazards posed by future eruptions at glaciated volcanoes. Title: Lava and Ice Interaction at Stratovolcanoes: Use of Characteristic Features to Determine Past Glacial Extents and Future Volcanic Hazards Author: Lescinsky, David T., Fink, Jonathan H. Year: 2000 Structures resulting from lava and ice interaction are common at glaciated stratovolcanoes. During summit eruptions at stratovolcanoes, meltwater is produced and travels freely down steep slopes and thin permeable valley glaciers, eroding the ice and enlarging preexisting glacial drainages. As a result, in this environment have produced few catastrophic floods. Lava flowing into the open channels and voids in the glaciers becomes confined and grows thicker, filling the available space and producing steep-sided bodies with smooth, bulbous contact surfaces. Quenching of lava against ice or by water forms small-scale features such as tensional fractures and glass. As the amount of meltwater in contact with the lava increases, the type and abundance of smaller-scale features become similar to those produced during subglacial eruptions in meltwater lakes. Identification of large- and small-scale lava-ice contact features in the field can be used to reconstruct paleoglacial extent and, combined with geochronology of lavas, to determine past paleoclimate. An understanding of lava-ice interaction allows us to better access the hazards posed by future eruptions at glaciated volcanoes. Close

• 55. [Article] Multiple Reoccupations after Four Paleotsunami Inundations (0.3–1.3 ka) at a Prehistoric Site in the Netarts Littoral Cell, Northern Oregon Coast, USA

  Netarts Bay is the setting of one of the largest concentrations of late prehistoric Native American settlements on the tectonically active Oregon coast. A prehistoric site (35TI74) exposed by sea cliff ...

  Citation × Citation Citation Abstract Copy Title: Multiple Reoccupations after Four Paleotsunami Inundations (0.3–1.3 ka) at a Prehistoric Site in the Netarts Littoral Cell, Northern Oregon Coast, USA Author: Minor, Rick, Peterson, Curt D. Year: 2017 Netarts Bay is the setting of one of the largest concentrations of late prehistoric Native American settlements on the tectonically active Oregon coast. A prehistoric site (35TI74) exposed by sea cliff erosion in 1998 at the south end of the Netarts littoral cell contained a stratigraphic record of activity by prehistoric Native Americans and interbedded paleotsunami deposits. The nearfield paleotsunamis were produced by great Cascadia earthquakes (Mw8.5 ± 0.5) emanating from the Cascadia Subduction Zone offshore, as previously documented in episodically buried tidal marsh surfaces at the south end of Netarts Bay and in many other estuaries in the region. The cultural deposits at 35TI74 reflect multiple reoccupations by Native Americans at this barrage creek flood plain site between paleotsunami runup events (≥7.5 m elevation) at 1.3 ka, 1.1 ka, 0.8–0.9 ka, and 0.3 ka. The conditions that led to the exposure of 35TI74 are traced to erosion of a protective beach dune ramp at the south end of the Netarts littoral cell, placing the site within reach of progressive storm-surf erosion. The diminishing geoarchaeological record at 35TI74 represents a microcosm of the sea cliff erosional processes that threaten vulnerable prehistoric shoreline archaeological sites along much of the Pacific Northwest Coast. Copyright © 2016 Wiley Periodicals, Inc. Title: Multiple Reoccupations after Four Paleotsunami Inundations (0.3–1.3 ka) at a Prehistoric Site in the Netarts Littoral Cell, Northern Oregon Coast, USA Author: Minor, Rick, Peterson, Curt D. Year: 2017 Netarts Bay is the setting of one of the largest concentrations of late prehistoric Native American settlements on the tectonically active Oregon coast. A prehistoric site (35TI74) exposed by sea cliff erosion in 1998 at the south end of the Netarts littoral cell contained a stratigraphic record of activity by prehistoric Native Americans and interbedded paleotsunami deposits. The nearfield paleotsunamis were produced by great Cascadia earthquakes (Mw8.5 ± 0.5) emanating from the Cascadia Subduction Zone offshore, as previously documented in episodically buried tidal marsh surfaces at the south end of Netarts Bay and in many other estuaries in the region. The cultural deposits at 35TI74 reflect multiple reoccupations by Native Americans at this barrage creek flood plain site between paleotsunami runup events (≥7.5 m elevation) at 1.3 ka, 1.1 ka, 0.8–0.9 ka, and 0.3 ka. The conditions that led to the exposure of 35TI74 are traced to erosion of a protective beach dune ramp at the south end of the Netarts littoral cell, placing the site within reach of progressive storm-surf erosion. The diminishing geoarchaeological record at 35TI74 represents a microcosm of the sea cliff erosional processes that threaten vulnerable prehistoric shoreline archaeological sites along much of the Pacific Northwest Coast. Copyright © 2016 Wiley Periodicals, Inc. Close

• 56. [Article] A People's Plan for Overcoming the Hurricane Katrina Blues: A Comprehensive Strategy for Building a More Vibrant, Sustainable, and Equitable 9th Ward

  The Peoples’ Plan is a strategic action plan for the recovery of the 9th Ward. We’ve created it based on conversations with residents – some struggling to return home, others intent on remaining in a neighborhood ...

  Citation × Citation Citation Abstract Copy Title: A People's Plan for Overcoming the Hurricane Katrina Blues: A Comprehensive Strategy for Building a More Vibrant, Sustainable, and Equitable 9th Ward Author: Hayes, Richard, Reardon, Ken, Bates, Lisa K. Year: 2007 The Peoples’ Plan is a strategic action plan for the recovery of the 9th Ward. We’ve created it based on conversations with residents – some struggling to return home, others intent on remaining in a neighborhood that has always been there own. The Peoples’ Plan provides a thorough assessment of what must be done to provide recovery in one of the hardest hit areas of the City, and provides a recovery model for all badly flooded areas. Our Plan seeks to transform the 9th Ward as it is rebuilt. The proposed transformation will be resident-driven and will provide improved employment opportunities, better education programs as well as greater access to healthcare, childcare and numerous other community services. Title: A People's Plan for Overcoming the Hurricane Katrina Blues: A Comprehensive Strategy for Building a More Vibrant, Sustainable, and Equitable 9th Ward Author: Hayes, Richard, Reardon, Ken, Bates, Lisa K. Year: 2007 The Peoples’ Plan is a strategic action plan for the recovery of the 9th Ward. We’ve created it based on conversations with residents – some struggling to return home, others intent on remaining in a neighborhood that has always been there own. The Peoples’ Plan provides a thorough assessment of what must be done to provide recovery in one of the hardest hit areas of the City, and provides a recovery model for all badly flooded areas. Our Plan seeks to transform the 9th Ward as it is rebuilt. The proposed transformation will be resident-driven and will provide improved employment opportunities, better education programs as well as greater access to healthcare, childcare and numerous other community services. Close

• 57. [Article] Vernonia 2020 Vision: A Plan for the Future

  The Vernonia 2020 Vision Plan was an endeavor by the City of Vernonia to involve citizens in long-term resiliency planning and visioning to complement the short-term recovery effort following a 500-year ...

  Citation × Citation Citation Abstract Copy Title: Vernonia 2020 Vision: A Plan for the Future Author: Berkow, Mathew, Ellis, Maria, Eshel, Oren, Kaur, Harleen, Lingley, Terra, Maher, Colin, Shackman, Stephen, Tipper, Ariana, Zaninovich, George Year: 2008 The Vernonia 2020 Vision Plan was an endeavor by the City of Vernonia to involve citizens in long-term resiliency planning and visioning to complement the short-term recovery effort following a 500-year flood in December 2007. Bridges Planning Group facilitated the process, over the course of which residents identified the highest-priority barriers to resiliency and past and present efforts to overcome these barriers. This project was conducted under the supervision of Sy Adler and Ethan Seltzer. Title: Vernonia 2020 Vision: A Plan for the Future Author: Berkow, Mathew, Ellis, Maria, Eshel, Oren, Kaur, Harleen, Lingley, Terra, Maher, Colin, Shackman, Stephen, Tipper, Ariana, Zaninovich, George Year: 2008 The Vernonia 2020 Vision Plan was an endeavor by the City of Vernonia to involve citizens in long-term resiliency planning and visioning to complement the short-term recovery effort following a 500-year flood in December 2007. Bridges Planning Group facilitated the process, over the course of which residents identified the highest-priority barriers to resiliency and past and present efforts to overcome these barriers. This project was conducted under the supervision of Sy Adler and Ethan Seltzer. Close

• 58. [Article] Interview with W. T. "Bill" Lemman

  In this interview with Michael O’Rourke, Mr. Lemman discusses his experiences and accomplishments from his undergraduate years at Vanport until his administrative position in Oregon higher education, and ...

  Citation × Citation Citation Abstract Copy Title: Interview with W. T. "Bill" Lemman Author: Lemman, W. T. "Bill", O’Rourke, Michael Year: 2010 In this interview with Michael O’Rourke, Mr. Lemman discusses his experiences and accomplishments from his undergraduate years at Vanport until his administrative position in Oregon higher education, and remembers faculty, students, and administrators with whom he worked to grow Portland State into an urban campus of almost thirty thousand students. Highlights include student life and media at Vanport Extension Center, the Vanport flood of 1948, urban renewal in Portland that facilitated the establishment of the campus during the 1960s and 70s, student housing, and collective bargaining with faculty and staff unions.This interview was recorded in two sittings on September 23 and September 27, 2010. Some portions of the interview have been edited for relevance to PSU history. The unabridged recording and transcript are available through Portland State University Archives at the PSU Library. Acknowledgements and thanks to RAPS, Retirement Association of Portland State University, for biographical information on Mr. Lemman. The abridged transcript of this interview is available for download. Title: Interview with W. T. "Bill" Lemman Author: Lemman, W. T. "Bill", O’Rourke, Michael Year: 2010 In this interview with Michael O’Rourke, Mr. Lemman discusses his experiences and accomplishments from his undergraduate years at Vanport until his administrative position in Oregon higher education, and remembers faculty, students, and administrators with whom he worked to grow Portland State into an urban campus of almost thirty thousand students. Highlights include student life and media at Vanport Extension Center, the Vanport flood of 1948, urban renewal in Portland that facilitated the establishment of the campus during the 1960s and 70s, student housing, and collective bargaining with faculty and staff unions.This interview was recorded in two sittings on September 23 and September 27, 2010. Some portions of the interview have been edited for relevance to PSU history. The unabridged recording and transcript are available through Portland State University Archives at the PSU Library. Acknowledgements and thanks to RAPS, Retirement Association of Portland State University, for biographical information on Mr. Lemman. The abridged transcript of this interview is available for download. Close

• 59. [Article] E-Books and Author Payments: The Affect of Digital Publishing on Author Royalties

  From digital rights management to retail costs, controversy has always accompanied ebooks— although it hasn’t even been a decade since Amazon first released the Kindle. This discussion, however, explores ...

  Citation × Citation Citation Abstract Copy Title: E-Books and Author Payments: The Affect of Digital Publishing on Author Royalties Author: Lacock, Missy Year: 2015 From digital rights management to retail costs, controversy has always accompanied ebooks— although it hasn’t even been a decade since Amazon first released the Kindle. This discussion, however, explores another question: How have e-books affected author payments? The most significant change in author payments has been e-book royalty rates. While the standard rates are seven and a half percent for trade paperback books and fifteen percent for hardcover books, royalty rates for e-books are twenty-five percent—the same today as they were when e-books first flooded the market in 2009. While royalty rates are higher for e-books than their printed counterparts, debates about digital royalty rates continue to surface at publishing conferences. Title: E-Books and Author Payments: The Affect of Digital Publishing on Author Royalties Author: Lacock, Missy Year: 2015 From digital rights management to retail costs, controversy has always accompanied ebooks— although it hasn’t even been a decade since Amazon first released the Kindle. This discussion, however, explores another question: How have e-books affected author payments? The most significant change in author payments has been e-book royalty rates. While the standard rates are seven and a half percent for trade paperback books and fifteen percent for hardcover books, royalty rates for e-books are twenty-five percent—the same today as they were when e-books first flooded the market in 2009. While royalty rates are higher for e-books than their printed counterparts, debates about digital royalty rates continue to surface at publishing conferences. Close

• 60. [Article] Climate Change Impacts on Precipitation Extremes over the Columbia River Basin Based on Downscaled CMIP5 Climate Scenarios

  Hydro-climate extreme analysis helps understanding the process of spatio-temporal variation of extreme events due to climate change, and it is an important aspect in designing hydrological structures, ...

  Citation × Citation Citation Abstract Copy Title: Climate Change Impacts on Precipitation Extremes over the Columbia River Basin Based on Downscaled CMIP5 Climate Scenarios Author: Dars, Ghulam Hussain Year: 2013 Hydro-climate extreme analysis helps understanding the process of spatio-temporal variation of extreme events due to climate change, and it is an important aspect in designing hydrological structures, forecasting floods and an effective decision making in the field of water resources design and management. The study evaluates extreme precipitation events over the Columbia River Basin (CRB), the fourth largest basin in the U.S., by simulating four CMIP5 global climate models (GCMs) for the historical period (1970-1999) and future period (2041-2070) under RCP85 GHG scenario. We estimated the intensity of extreme and average precipitation for both winter (DJF) and summer (JJA) seasons by using the GEV distribution and multi-model ensemble average over the domain of the Columbia River Basin. The four CMIP5 models performed very well at simulating precipitation extremes in the winter season. The CMIP5 climate models showed heterogeneous spatial pattern of summer extreme precipitation over the CRB for the future period. It was noticed that multi-model ensemble mean outperformed compared to the individual performance of climate models for both seasons. We have found that the multi-model ensemble shows a consistent and significant increase in the extreme precipitation events in the west of the Cascades Range, Coastal Ranges of Oregon and Washington State, the Canadian portion of the basin and over the Rocky Mountains. However, the mean precipitation is projected to decrease in both winter and summer seasons in the future period. The Columbia River is dominated by the glacial snowmelt, so the increase in the intensity of extreme precipitation and decrease in mean precipitation in the future period, as simulated by four CMIP5 models, is expected to aggravate the earlier snowmelt and contribute to the flooding in the low lying areas especially in the west of the Cascades Range. In addition, the climate change shift could have serious implications on transboundary water issues in between the United States and Canada. Therefore, adaptation strategies should be devised to cope the possible adverse effects of the changing the future climate so that it could have minimal influence on hydrology, agriculture, aquatic species, hydro-power generation, human health and other water related infrastructure. Title: Climate Change Impacts on Precipitation Extremes over the Columbia River Basin Based on Downscaled CMIP5 Climate Scenarios Author: Dars, Ghulam Hussain Year: 2013 Hydro-climate extreme analysis helps understanding the process of spatio-temporal variation of extreme events due to climate change, and it is an important aspect in designing hydrological structures, forecasting floods and an effective decision making in the field of water resources design and management. The study evaluates extreme precipitation events over the Columbia River Basin (CRB), the fourth largest basin in the U.S., by simulating four CMIP5 global climate models (GCMs) for the historical period (1970-1999) and future period (2041-2070) under RCP85 GHG scenario. We estimated the intensity of extreme and average precipitation for both winter (DJF) and summer (JJA) seasons by using the GEV distribution and multi-model ensemble average over the domain of the Columbia River Basin. The four CMIP5 models performed very well at simulating precipitation extremes in the winter season. The CMIP5 climate models showed heterogeneous spatial pattern of summer extreme precipitation over the CRB for the future period. It was noticed that multi-model ensemble mean outperformed compared to the individual performance of climate models for both seasons. We have found that the multi-model ensemble shows a consistent and significant increase in the extreme precipitation events in the west of the Cascades Range, Coastal Ranges of Oregon and Washington State, the Canadian portion of the basin and over the Rocky Mountains. However, the mean precipitation is projected to decrease in both winter and summer seasons in the future period. The Columbia River is dominated by the glacial snowmelt, so the increase in the intensity of extreme precipitation and decrease in mean precipitation in the future period, as simulated by four CMIP5 models, is expected to aggravate the earlier snowmelt and contribute to the flooding in the low lying areas especially in the west of the Cascades Range. In addition, the climate change shift could have serious implications on transboundary water issues in between the United States and Canada. Therefore, adaptation strategies should be devised to cope the possible adverse effects of the changing the future climate so that it could have minimal influence on hydrology, agriculture, aquatic species, hydro-power generation, human health and other water related infrastructure. Close

• 61. [Article] Gun Running in Arabia: The Introduction of Modern Arms to the Peninsula, 1880-1914

  Modern breech-loading rifles flooded into Arabia and the region around the Persian Gulf between 1880 and World War I. This work examines in detail, and analyzes, the introduction of modern arms to Arabia, ...

  Citation × Citation Citation Abstract Copy Title: Gun Running in Arabia: The Introduction of Modern Arms to the Peninsula, 1880-1914 Author: Fiscus, James W. Year: 1987 Modern breech-loading rifles flooded into Arabia and the region around the Persian Gulf between 1880 and World War I. This work examines in detail, and analyzes, the introduction of modern arms to Arabia, the origin of those arms, the trade patterns by which they were moved, and the international and local political factors that affected the trade. The international arms trade was driven by three major factors. First, the rapid technological development of small arms in the nineteenth century fed the market, resulting in the availability of hundreds of thousands of obsolete military rifles for resale. Each time new rifles were adopted by the armies of Europe, old stocks were dumped on the private arms market. Second, international politics and European colonial rivalry contributed to the growth and maintenance of the arms trade. The French Consul at Muscat protected the trade in the Persian Gulf, while French arms dealers commanded a substantial portion of the trade. British efforts to slow the flow of arms through Muscat was hampered by European politics. Third, the internal politics of the region created a demand for the modern arms. Inside Arabia, the resurgent Saudis fought Rashidis and Hashimites in a series of wars, while other tribal raids and wars further built the demand for modern rifles: if one group had modern weapons, its enemies felt a need for them also. Outside Arabia, a strong demand for weapons in Persia and on the Northwest Frontier of India helped pull weapons to the markets of the Gulf. This thesis deals first with the changing technology of weapons in the nineteenth century, so that the military impact of the new weapons can be understood. The types of modern rifles introduced to the Peninsula is then reviewed, finding that the Peabody-Martini and the Martini-Henry, and their numerous variations, were the weapons most commonly imported in the decades around the turn of the century. With this information as background, the international politics of the arms trade are examined. Emphasis is on the Anglo-French rivalry at Muscat that gave treaty protection to French arms dealers. European fears that modern arms would reach Africa and make colonial control of the continent difficult or impossible led, in 1890, to the arms control provisions of the General Act of Brussels. The Act did not, however, extend to Arabia. The heart of the work is a detailed examination and analysis of the arms trade in and around Arabia. The arms trade in the region was centered in two main entrepots, Djibouti in French Somaliland and Muscat in southeast Arabia. By the late l890s, the bulk of the trade was passing through the Suez Canal before transshipment at one of these ports. Just over half of the arms reaching Muscat were exported to Persia and the Northwest Frontier, with the remainder reaching Arabia or Mesopotamia. The patterns of the private arms trade were complex, both at sea and on land, and are discussed at length. The political use of weapons by the Ottoman Government, and by European states, contributed to the flood of guns into Arabia. The Ottomans, in particular, used their stocks of obsolete weapons to arm their client tribes in Arabia. Ottoman purchases of Sniders, Martinis, and finally Mausers, gave them a constant supply of older rifles for distribution. The arms trade in Arabia was controlled by international and local political developments, and fed by the availability of modern arms on the international market. The trade was complex and impossible to prevent so long as the European states and the Ottomans continued to sell or distribute obsolete rifles as new guns were adopted. Title: Gun Running in Arabia: The Introduction of Modern Arms to the Peninsula, 1880-1914 Author: Fiscus, James W. Year: 1987 Modern breech-loading rifles flooded into Arabia and the region around the Persian Gulf between 1880 and World War I. This work examines in detail, and analyzes, the introduction of modern arms to Arabia, the origin of those arms, the trade patterns by which they were moved, and the international and local political factors that affected the trade. The international arms trade was driven by three major factors. First, the rapid technological development of small arms in the nineteenth century fed the market, resulting in the availability of hundreds of thousands of obsolete military rifles for resale. Each time new rifles were adopted by the armies of Europe, old stocks were dumped on the private arms market. Second, international politics and European colonial rivalry contributed to the growth and maintenance of the arms trade. The French Consul at Muscat protected the trade in the Persian Gulf, while French arms dealers commanded a substantial portion of the trade. British efforts to slow the flow of arms through Muscat was hampered by European politics. Third, the internal politics of the region created a demand for the modern arms. Inside Arabia, the resurgent Saudis fought Rashidis and Hashimites in a series of wars, while other tribal raids and wars further built the demand for modern rifles: if one group had modern weapons, its enemies felt a need for them also. Outside Arabia, a strong demand for weapons in Persia and on the Northwest Frontier of India helped pull weapons to the markets of the Gulf. This thesis deals first with the changing technology of weapons in the nineteenth century, so that the military impact of the new weapons can be understood. The types of modern rifles introduced to the Peninsula is then reviewed, finding that the Peabody-Martini and the Martini-Henry, and their numerous variations, were the weapons most commonly imported in the decades around the turn of the century. With this information as background, the international politics of the arms trade are examined. Emphasis is on the Anglo-French rivalry at Muscat that gave treaty protection to French arms dealers. European fears that modern arms would reach Africa and make colonial control of the continent difficult or impossible led, in 1890, to the arms control provisions of the General Act of Brussels. The Act did not, however, extend to Arabia. The heart of the work is a detailed examination and analysis of the arms trade in and around Arabia. The arms trade in the region was centered in two main entrepots, Djibouti in French Somaliland and Muscat in southeast Arabia. By the late l890s, the bulk of the trade was passing through the Suez Canal before transshipment at one of these ports. Just over half of the arms reaching Muscat were exported to Persia and the Northwest Frontier, with the remainder reaching Arabia or Mesopotamia. The patterns of the private arms trade were complex, both at sea and on land, and are discussed at length. The political use of weapons by the Ottoman Government, and by European states, contributed to the flood of guns into Arabia. The Ottomans, in particular, used their stocks of obsolete weapons to arm their client tribes in Arabia. Ottoman purchases of Sniders, Martinis, and finally Mausers, gave them a constant supply of older rifles for distribution. The arms trade in Arabia was controlled by international and local political developments, and fed by the availability of modern arms on the international market. The trade was complex and impossible to prevent so long as the European states and the Ottomans continued to sell or distribute obsolete rifles as new guns were adopted. Close

• 62. [Article] Coupling the Hydrodynamic and Water Quality Model CE-QUAL-W2 With a Multi-Trophic Fish Bio-Energetics Model for Lake Roosevelt, Washington

  Grand Coulee Dam created Franklin D. Roosevelt Lake as part of the Columbia Basin Project. Located in northeastern Washington State, the Project provides economically important hydropower (19 billion kilowatt ...

  Citation × Citation Citation Abstract Copy Title: Coupling the Hydrodynamic and Water Quality Model CE-QUAL-W2 With a Multi-Trophic Fish Bio-Energetics Model for Lake Roosevelt, Washington Author: McKillip, Michael Lee Year: 2008 Grand Coulee Dam created Franklin D. Roosevelt Lake as part of the Columbia Basin Project. Located in northeastern Washington State, the Project provides economically important hydropower (19 billion kilowatt hours per year), irrigation (225,000 ha), flood control, and sport fishing ($5 to 20 million annually). A good system understanding aids in balancing these beneficial uses for the 230 km long reservoir. The reservoir's atypical 45-day mean residence time is much shorter than a typical lake, and much longer than for a riverine dam. The spring freshet requires drawdowns of 15 to 20 m for flood control—the driving characteristic of reservoir operations. A physically based two-dimensional hydrodynamic and water quality model, CE-QUAL-W2 Version 3.5 (Cole and Wells, 2006), is coupled with a fish bioenergetics model based on the Stockwell and Johnson model (1997, 1999) to examine the effects of hydrodynamics on the reservoir algae-zooplankton-kokanee food web. This model was applied and calibrated to Lake Roosevelt with model improvements of multiple zooplankton compartments and zooplankton omnivory. Calibration parameters included temperature, dissolved oxygen, nutrients, algae, and zooplankton. The fish bioenergetics model is applied over the entire reservoir model space to generate a spatial and temporal fish growth potential distribution. The fish model refinements include sub-daily time-steps and an optimized vertical foraging strategy. The linked model suggests that kokanee fish growth potential is seasonally limited by both warm water and prey densities. While the lake ecology is significantly affected by the reservoir operations in general, the pelagic fish growth potential did not appear sensitive to minor changes in reservoir operations. However, the model suggests that the advantageous foraging locations shift seasonally and that optimal foraging strategies are dependent on fish size. Title: Coupling the Hydrodynamic and Water Quality Model CE-QUAL-W2 With a Multi-Trophic Fish Bio-Energetics Model for Lake Roosevelt, Washington Author: McKillip, Michael Lee Year: 2008 Grand Coulee Dam created Franklin D. Roosevelt Lake as part of the Columbia Basin Project. Located in northeastern Washington State, the Project provides economically important hydropower (19 billion kilowatt hours per year), irrigation (225,000 ha), flood control, and sport fishing ($5 to 20 million annually). A good system understanding aids in balancing these beneficial uses for the 230 km long reservoir. The reservoir's atypical 45-day mean residence time is much shorter than a typical lake, and much longer than for a riverine dam. The spring freshet requires drawdowns of 15 to 20 m for flood control—the driving characteristic of reservoir operations. A physically based two-dimensional hydrodynamic and water quality model, CE-QUAL-W2 Version 3.5 (Cole and Wells, 2006), is coupled with a fish bioenergetics model based on the Stockwell and Johnson model (1997, 1999) to examine the effects of hydrodynamics on the reservoir algae-zooplankton-kokanee food web. This model was applied and calibrated to Lake Roosevelt with model improvements of multiple zooplankton compartments and zooplankton omnivory. Calibration parameters included temperature, dissolved oxygen, nutrients, algae, and zooplankton. The fish bioenergetics model is applied over the entire reservoir model space to generate a spatial and temporal fish growth potential distribution. The fish model refinements include sub-daily time-steps and an optimized vertical foraging strategy. The linked model suggests that kokanee fish growth potential is seasonally limited by both warm water and prey densities. While the lake ecology is significantly affected by the reservoir operations in general, the pelagic fish growth potential did not appear sensitive to minor changes in reservoir operations. However, the model suggests that the advantageous foraging locations shift seasonally and that optimal foraging strategies are dependent on fish size. Close

• 63. [Article] Water Flow through Temperate Glaciers

  Understanding water movement through a glacier is fundamental to several critical issues in glaciology, including glacier dynamics, glacier-induced floods, and the prediction of runoff from glacierized ...

  Citation × Citation Citation Abstract Copy Title: Water Flow through Temperate Glaciers Author: Fountain, Andrew G., Walder, Joseph S. Year: 1998 Understanding water movement through a glacier is fundamental to several critical issues in glaciology, including glacier dynamics, glacier-induced floods, and the prediction of runoff from glacierized drainage basins. To this end we have synthesized a conceptual model of water movement through a temperate glacier from the surface to the outlet stream. Processes that regulate the rate and distribution of water input at the glacier surface and that regulate water movement from the surface to the bed play important but commonly neglected roles in glacier hydrology. Where a glacier is covered by a layer of porous, permeable firn (the accumulation zone), the flux of water to the glacier interior varies slowly because the firn temporarily stores water and thereby smooths out variations in the supply rate. In the firn-free ablation zone, in contrast, the flux of water into the glacier depends directly on the rate of surface melt or rainfall and therefore varies greatly in time. Water moves from the surface to the bed through an upward branching arborescent network consisting of both steeply inclined conduits, formed by the enlargement of intergranular veins, and gently inclined conduits, spawned by water flow along the bottoms of near-surface fractures (crevasses). Englacial drainage conduits deliver water to the glacier bed at a limited number of points, probably a long distance downglacier of where water enters the glacier. Englacial conduits supplied from the accumulation zone are quasi steady state features that convey the slowly varying water flux delivered via the firn. Their size adjusts so that they are usually full of water and flow is pressurized. In contrast, water flow in englacial conduits supplied from the ablation area is pressurized only near times of peak daily flow or during rainstorms; flow is otherwise in an open-channel configuration. The subglacial drainage system typically consists of several elements that are distinct both morphologically and hydrologically. An upglacier branching, arborescent network of channels incised into the basal ice conveys water rapidly. Much of the water flux to the bed probably enters directly into the arborescent channel network, which covers only a small fraction of the glacier bed. More extensive spatially is a nonarborescent network, which commonly includes cavities (gaps between the glacier sole and bed), channels incised into the bed, and a layer of permeable sediment. The nonarborescent network conveys water slowly and is usually poorly connected to the arborescent system. The arborescent channel network largely collapses during winter but reforms in the spring as the first flush of meltwater to the bed destabilizes the cavities within the nonarborescent network. The volume of water stored by a glacier varies diurnally and seasonally. Small, temperate alpine glaciers seem to attain a maximum seasonal water storage of approximately 200 mm of water averaged over the area of the glacier bed, with daily fluctuations of as much as 20-30 mm. The likely storage capacity of subglacial cavities is insufficient to account for estimated stored water volumes, so most water storage may actually occur englacially. Stored water may also be released abruptly and catastrophically in the form of outburst floods. Title: Water Flow through Temperate Glaciers Author: Fountain, Andrew G., Walder, Joseph S. Year: 1998 Understanding water movement through a glacier is fundamental to several critical issues in glaciology, including glacier dynamics, glacier-induced floods, and the prediction of runoff from glacierized drainage basins. To this end we have synthesized a conceptual model of water movement through a temperate glacier from the surface to the outlet stream. Processes that regulate the rate and distribution of water input at the glacier surface and that regulate water movement from the surface to the bed play important but commonly neglected roles in glacier hydrology. Where a glacier is covered by a layer of porous, permeable firn (the accumulation zone), the flux of water to the glacier interior varies slowly because the firn temporarily stores water and thereby smooths out variations in the supply rate. In the firn-free ablation zone, in contrast, the flux of water into the glacier depends directly on the rate of surface melt or rainfall and therefore varies greatly in time. Water moves from the surface to the bed through an upward branching arborescent network consisting of both steeply inclined conduits, formed by the enlargement of intergranular veins, and gently inclined conduits, spawned by water flow along the bottoms of near-surface fractures (crevasses). Englacial drainage conduits deliver water to the glacier bed at a limited number of points, probably a long distance downglacier of where water enters the glacier. Englacial conduits supplied from the accumulation zone are quasi steady state features that convey the slowly varying water flux delivered via the firn. Their size adjusts so that they are usually full of water and flow is pressurized. In contrast, water flow in englacial conduits supplied from the ablation area is pressurized only near times of peak daily flow or during rainstorms; flow is otherwise in an open-channel configuration. The subglacial drainage system typically consists of several elements that are distinct both morphologically and hydrologically. An upglacier branching, arborescent network of channels incised into the basal ice conveys water rapidly. Much of the water flux to the bed probably enters directly into the arborescent channel network, which covers only a small fraction of the glacier bed. More extensive spatially is a nonarborescent network, which commonly includes cavities (gaps between the glacier sole and bed), channels incised into the bed, and a layer of permeable sediment. The nonarborescent network conveys water slowly and is usually poorly connected to the arborescent system. The arborescent channel network largely collapses during winter but reforms in the spring as the first flush of meltwater to the bed destabilizes the cavities within the nonarborescent network. The volume of water stored by a glacier varies diurnally and seasonally. Small, temperate alpine glaciers seem to attain a maximum seasonal water storage of approximately 200 mm of water averaged over the area of the glacier bed, with daily fluctuations of as much as 20-30 mm. The likely storage capacity of subglacial cavities is insufficient to account for estimated stored water volumes, so most water storage may actually occur englacially. Stored water may also be released abruptly and catastrophically in the form of outburst floods. Close

• 64. [Article] Methane and Nitrous Oxide Emissions From Subtropical Rice Agriculture in China

  Emissions of methane and nitrous oxide, two significant greenhouse gases, were measured from rice fields at Qingyuan in Guangdong Province, China. The region has a subtropical climate which allows two ...

  Citation × Citation Citation Abstract Copy Title: Methane and Nitrous Oxide Emissions From Subtropical Rice Agriculture in China Author: Khalil, M. A. K., Shearer, Martha J., Rasmussen, R. A., Xu, Li, Liu, Jin-Luan Year: 2008 Emissions of methane and nitrous oxide, two significant greenhouse gases, were measured from rice fields at Qingyuan in Guangdong Province, China. The region has a subtropical climate which allows two crops of rice to be grown every year. The prevailing agricultural practices create a complex interaction between factors known to have a major effect on methane and nitrous oxide emissions from rice fields, namely, intermittent flooding and use of organic fertilizers. In this region, the farmers depend on nitrogen fertilizers and, at least in recent years, have only intermittently flooded their fields during the growing seasons. These factors tend to reduce methane emissions. But the rice straw and crop residues from the first crop of the year are plowed into the fields, providing a large addition of organic material under hot weather conditions favorable to quick decomposition during the second crop period. This, and the addition of farmyard manure, increases emissions of methane emissions from these fields. The results of the present study show that the effect of these competing factors and their timing lead to an average rate of emissions of 5 ± 2 and 6 ± 2 mg/m2/h from the first crops for the 2 years when measurements were taken (2003 and 2004), and 12 ± 8 and 13 ± 8 mg/m2/h from the second crop. Further, production measurements showed that during the 2 years of these experiments, the average production rates were about 27 mg/m2/h for the first crop and 22–34 mg/m2/h for the second crop, resulting in estimated oxidation rates of about 80% for the first crop and 50–60% for the second crop. The higher fluxes in the second crop therefore appear to be caused more by reduced oxidation than higher production. Nitrous oxide emissions, when they were detected, usually occurred within a few days after the application of nitrogen fertilizers. The seasonally averaged emissions were between 0.01 and 0.02 mg/m2/h except in the first year when large emissions over one short period pushed the average upward Title: Methane and Nitrous Oxide Emissions From Subtropical Rice Agriculture in China Author: Khalil, M. A. K., Shearer, Martha J., Rasmussen, R. A., Xu, Li, Liu, Jin-Luan Year: 2008 Emissions of methane and nitrous oxide, two significant greenhouse gases, were measured from rice fields at Qingyuan in Guangdong Province, China. The region has a subtropical climate which allows two crops of rice to be grown every year. The prevailing agricultural practices create a complex interaction between factors known to have a major effect on methane and nitrous oxide emissions from rice fields, namely, intermittent flooding and use of organic fertilizers. In this region, the farmers depend on nitrogen fertilizers and, at least in recent years, have only intermittently flooded their fields during the growing seasons. These factors tend to reduce methane emissions. But the rice straw and crop residues from the first crop of the year are plowed into the fields, providing a large addition of organic material under hot weather conditions favorable to quick decomposition during the second crop period. This, and the addition of farmyard manure, increases emissions of methane emissions from these fields. The results of the present study show that the effect of these competing factors and their timing lead to an average rate of emissions of 5 ± 2 and 6 ± 2 mg/m2/h from the first crops for the 2 years when measurements were taken (2003 and 2004), and 12 ± 8 and 13 ± 8 mg/m2/h from the second crop. Further, production measurements showed that during the 2 years of these experiments, the average production rates were about 27 mg/m2/h for the first crop and 22–34 mg/m2/h for the second crop, resulting in estimated oxidation rates of about 80% for the first crop and 50–60% for the second crop. The higher fluxes in the second crop therefore appear to be caused more by reduced oxidation than higher production. Nitrous oxide emissions, when they were detected, usually occurred within a few days after the application of nitrogen fertilizers. The seasonally averaged emissions were between 0.01 and 0.02 mg/m2/h except in the first year when large emissions over one short period pushed the average upward Close

• 65. [Article] Calculating the Volume of the May 18, 1980 Eruption of Mount St. Helens

  The May 18, 1980 eruption of Mount St. Helens created a massive amount of sediment and debris, thought to be as much as 5.5 billion cubic yards. This sediment causes infill of river stretches and collects ...

  Citation × Citation Citation Abstract Copy Title: Calculating the Volume of the May 18, 1980 Eruption of Mount St. Helens Author: Wickham, Dâvid Nuñez Year: 2009 The May 18, 1980 eruption of Mount St. Helens created a massive amount of sediment and debris, thought to be as much as 5.5 billion cubic yards. This sediment causes infill of river stretches and collects along levees protecting southwest Washington State. The sediment must be removed to ensure these areas do not flood. The US Army Corps of Engineers (USACOE) is tasked with flood protection for southwest Washington State and the levees protecting the cities of Castle Rock, Lexington, Kelso, and Longview. The Sediment Retention Dam, opened in 1989 is able to filter out larger particulate but fine grain sediment remains in the water column and is transported further down the river. In order to calculate how much sediment remains to be removed Portland State University’s Environmental Sciences and Management program and the USACOE formed a partnership and generated Digital Elevation Models (DEM) from topographic maps made by the United States Geological Survey (USGS). This was accomplished by taking 600 dots per inch (dpi) scanned images of the eruption path, geographically rectifying them in ESRI’s ArcMap software environment, and running Iterative Self-Organizing Data Analysis Technique (ISODATA) Unsupervised Classification utilizing ERDAS Imagine 9.3 software. After the contour lines were extracted from the images we cleaned up the lines in a raster environment, converted the raster to vector lines, and entered elevations. From these contour lines we created the DEM and calculated the volume difference between the pre-eruption 15 minute USGS maps and the 7.5 minute post-eruption quad maps. The volume difference was 7,870,546,345 m3 for Mount St. Helens quads, - 4,335,917,517 m3 for Spirit Lake quads, -220,149,557 m3 for Goat Mtn. in Cougar quads, -3,155,437,891 m3 for Elk Rock quads, and 734,102,545 m3 for Hoffstadt Mtn. in Elk Rock pre quad. These figures indicated a large generation of sediment and debris on the slope north of Mount St. Helens, sediment deposition in the Hoffstadt Mtn. river reach, and erosion in all other areas. The USACOE will use my raw data contour elevation lines to create their own DEMs incorporating stream locations to further refine the data. From this data they hope to extrapolate how much sediment is left and where the sediment deposits are likely to erode from in the future. Title: Calculating the Volume of the May 18, 1980 Eruption of Mount St. Helens Author: Wickham, Dâvid Nuñez Year: 2009 The May 18, 1980 eruption of Mount St. Helens created a massive amount of sediment and debris, thought to be as much as 5.5 billion cubic yards. This sediment causes infill of river stretches and collects along levees protecting southwest Washington State. The sediment must be removed to ensure these areas do not flood. The US Army Corps of Engineers (USACOE) is tasked with flood protection for southwest Washington State and the levees protecting the cities of Castle Rock, Lexington, Kelso, and Longview. The Sediment Retention Dam, opened in 1989 is able to filter out larger particulate but fine grain sediment remains in the water column and is transported further down the river. In order to calculate how much sediment remains to be removed Portland State University’s Environmental Sciences and Management program and the USACOE formed a partnership and generated Digital Elevation Models (DEM) from topographic maps made by the United States Geological Survey (USGS). This was accomplished by taking 600 dots per inch (dpi) scanned images of the eruption path, geographically rectifying them in ESRI’s ArcMap software environment, and running Iterative Self-Organizing Data Analysis Technique (ISODATA) Unsupervised Classification utilizing ERDAS Imagine 9.3 software. After the contour lines were extracted from the images we cleaned up the lines in a raster environment, converted the raster to vector lines, and entered elevations. From these contour lines we created the DEM and calculated the volume difference between the pre-eruption 15 minute USGS maps and the 7.5 minute post-eruption quad maps. The volume difference was 7,870,546,345 m3 for Mount St. Helens quads, - 4,335,917,517 m3 for Spirit Lake quads, -220,149,557 m3 for Goat Mtn. in Cougar quads, -3,155,437,891 m3 for Elk Rock quads, and 734,102,545 m3 for Hoffstadt Mtn. in Elk Rock pre quad. These figures indicated a large generation of sediment and debris on the slope north of Mount St. Helens, sediment deposition in the Hoffstadt Mtn. river reach, and erosion in all other areas. The USACOE will use my raw data contour elevation lines to create their own DEMs incorporating stream locations to further refine the data. From this data they hope to extrapolate how much sediment is left and where the sediment deposits are likely to erode from in the future. Close

• 66. [Article] Faulty Measurements and Shaky Tools: An Exploration into Hazus and the Seismic Vulnerabilities of Portland, OR

  Events or forces of nature with catastrophic consequences, or "natural disasters," have increased in both frequency and force due to climate change and increased urbanization in climate-sensitive areas. ...

  Citation × Citation Citation Abstract Copy Title: Faulty Measurements and Shaky Tools: An Exploration into Hazus and the Seismic Vulnerabilities of Portland, OR Author: Brannon, Brittany Ann Year: 2013 Events or forces of nature with catastrophic consequences, or "natural disasters," have increased in both frequency and force due to climate change and increased urbanization in climate-sensitive areas. To create capacity to face these dangers, an entity must first quantify the threat and translate scientific knowledge on nature into comprehensible estimates of cost and loss. These estimates equip those at risk with knowledge to enact policy, formulate mitigation plans, raise awareness, and promote preparedness in light of potential destruction. Hazards-United States, or Hazus, is one such tool created by the federal government to estimate loss from a variety of threats, including earthquakes, hurricanes, and floods. Private and governmental agencies use Hazus to provide information and support to enact mitigation measures, craft plans, and create insurance assessments; hence the results of Hazus can have lasting and irreversible effects once the hazard in question occurs. This thesis addresses this problem and sheds light on the obvious and deterministic failings of Hazus in the context of the probable earthquake in Portland, OR; stripping away the tool's black box and exposing the grim vulnerabilities it fails to account for. The purpose of this thesis is twofold. First, this thesis aims to examine the critical flaws within Hazus and the omitted vulnerabilities particular to the Portland region and likely relevant in other areas of study. Second and more nationally applicable, this thesis intends to examine the influence Hazus outputs can have in the framing of seismic risk by the non-expert public. Combining the problem of inadequate understanding of risk in Portland with the questionable faith in Hazus alludes to a larger, socio-technical situation in need of attention by the academic and hazard mitigation community. This thesis addresses those issues in scope and adds to the growing body of literature on defining risk, hazard mitigation, and the consequences of natural disasters to urban environments. Title: Faulty Measurements and Shaky Tools: An Exploration into Hazus and the Seismic Vulnerabilities of Portland, OR Author: Brannon, Brittany Ann Year: 2013 Events or forces of nature with catastrophic consequences, or "natural disasters," have increased in both frequency and force due to climate change and increased urbanization in climate-sensitive areas. To create capacity to face these dangers, an entity must first quantify the threat and translate scientific knowledge on nature into comprehensible estimates of cost and loss. These estimates equip those at risk with knowledge to enact policy, formulate mitigation plans, raise awareness, and promote preparedness in light of potential destruction. Hazards-United States, or Hazus, is one such tool created by the federal government to estimate loss from a variety of threats, including earthquakes, hurricanes, and floods. Private and governmental agencies use Hazus to provide information and support to enact mitigation measures, craft plans, and create insurance assessments; hence the results of Hazus can have lasting and irreversible effects once the hazard in question occurs. This thesis addresses this problem and sheds light on the obvious and deterministic failings of Hazus in the context of the probable earthquake in Portland, OR; stripping away the tool's black box and exposing the grim vulnerabilities it fails to account for. The purpose of this thesis is twofold. First, this thesis aims to examine the critical flaws within Hazus and the omitted vulnerabilities particular to the Portland region and likely relevant in other areas of study. Second and more nationally applicable, this thesis intends to examine the influence Hazus outputs can have in the framing of seismic risk by the non-expert public. Combining the problem of inadequate understanding of risk in Portland with the questionable faith in Hazus alludes to a larger, socio-technical situation in need of attention by the academic and hazard mitigation community. This thesis addresses those issues in scope and adds to the growing body of literature on defining risk, hazard mitigation, and the consequences of natural disasters to urban environments. Close

• 67. [Article] Factors affecting the population of raptorial birds on Sauvie Island, Oregon

  This study is an analysis of the various factors affecting the population of raptorial birds on Sauvie Island, Oregon. A census of diurnal and nocturnal raptors was carried out along with an analysis of ...

  Citation × Citation Citation Abstract Copy Title: Factors affecting the population of raptorial birds on Sauvie Island, Oregon Author: Gottfried, Jeffry Year: 1972 This study is an analysis of the various factors affecting the population of raptorial birds on Sauvie Island, Oregon. A census of diurnal and nocturnal raptors was carried out along with an analysis of food habits. Once the major prey species were determined they were censused, and the effects of the land management practices on their numbers was investigated. In addition, 100 randomly selected nest boxes were sampled so as to determine the extent to which raptors were making use of them. Red-tailed hawk and Great Horned Owl nests were located It was found that four diurnal raptors and three nocturnal raptors were present in sizeable numbers on Sauvie during the winter and spring of 1972. In addition here were less common sightings of four diurnal and one nocturnal raptor. The most common food item of raptors in general was the vole, Microtus townsendi, which was later found to be present in extremely high numbers. The common practice of planting fields of grains and the intentional flooding of them (for waterfowl use) was found to be a major factor in the numbers and vulnerability of Microtus townsendi. Ducks were a common food item for all raptorial species during and immediately after duck hunting season, but not at any other time of year which seemed to indicate that the raptors were feeding on carrion or wounded ducks. It was found that Barn Owls (Tyto alba), Screech Owls (Otis asio) and Kestrel (Falco sparvarius) made use of the nest boxes on Sauvie Island. The overlapping of food habits of Sauvie Island raptors was discussed and an attempt was made to reconcile the apparent contradiction to Gause’s Rule. Title: Factors affecting the population of raptorial birds on Sauvie Island, Oregon Author: Gottfried, Jeffry Year: 1972 This study is an analysis of the various factors affecting the population of raptorial birds on Sauvie Island, Oregon. A census of diurnal and nocturnal raptors was carried out along with an analysis of food habits. Once the major prey species were determined they were censused, and the effects of the land management practices on their numbers was investigated. In addition, 100 randomly selected nest boxes were sampled so as to determine the extent to which raptors were making use of them. Red-tailed hawk and Great Horned Owl nests were located It was found that four diurnal raptors and three nocturnal raptors were present in sizeable numbers on Sauvie during the winter and spring of 1972. In addition here were less common sightings of four diurnal and one nocturnal raptor. The most common food item of raptors in general was the vole, Microtus townsendi, which was later found to be present in extremely high numbers. The common practice of planting fields of grains and the intentional flooding of them (for waterfowl use) was found to be a major factor in the numbers and vulnerability of Microtus townsendi. Ducks were a common food item for all raptorial species during and immediately after duck hunting season, but not at any other time of year which seemed to indicate that the raptors were feeding on carrion or wounded ducks. It was found that Barn Owls (Tyto alba), Screech Owls (Otis asio) and Kestrel (Falco sparvarius) made use of the nest boxes on Sauvie Island. The overlapping of food habits of Sauvie Island raptors was discussed and an attempt was made to reconcile the apparent contradiction to Gause’s Rule. Close

• 68. [Article] Guild's Lake Courts : an impermanent housing project

  Guild's Lake Courts was built as temporary worker housing for the steel and shipyard industries during World War II. The massive housing development in Northwest Portland consisted of 2,432 units of housing, ...

  Citation × Citation Citation Abstract Copy Title: Guild's Lake Courts : an impermanent housing project Author: March, Tanya Lyn Year: 2010 Guild's Lake Courts was built as temporary worker housing for the steel and shipyard industries during World War II. The massive housing development in Northwest Portland consisted of 2,432 units of housing, five community buildings, five childcare centers, a grade school and a fire station. Guild's Lake Courts was the eighth largest housing project built at that time in the United States. The peak population in January 1945 was approximately 10,000 individuals. Archival research, face-to-face oral histories, and resident reunions were used to explore the social, architectural and political history of Guild's Lake Courts. The lens for understanding how the community operated is dominantly for the social history that of a childhood homefront experience. Four wartime themes emerged in this study: 1) that Portland's focus on prejudice dimmed during the war years, 2) that the community was a confluence of humanity, 3) that the design of the site and the housing was shaped by a convergence of New Deal innovations in design construction technologies and electrification and 4) that there was a willingness to sacrifice creature comforts during the war years. Guild's Lake Courts as a residential community under went three rapid evolutions prior to its demolition in 1951, a wartime housing operation 1942-1945, affordable housing 1945-1948, and a haven for Vanport Refugees June 1948-1950. Guild's Lake Courts history has been overlooked but it offers insights into the possible fate of the residents of Vanport City had the community not been flooded in 1948. The story of Guild's Lake Courts is a counterpoint story to Vanport City the largest of the three defense housing projects in Oregon that admitted African-Americans during the war years. Title: Guild's Lake Courts : an impermanent housing project Author: March, Tanya Lyn Year: 2010 Guild's Lake Courts was built as temporary worker housing for the steel and shipyard industries during World War II. The massive housing development in Northwest Portland consisted of 2,432 units of housing, five community buildings, five childcare centers, a grade school and a fire station. Guild's Lake Courts was the eighth largest housing project built at that time in the United States. The peak population in January 1945 was approximately 10,000 individuals. Archival research, face-to-face oral histories, and resident reunions were used to explore the social, architectural and political history of Guild's Lake Courts. The lens for understanding how the community operated is dominantly for the social history that of a childhood homefront experience. Four wartime themes emerged in this study: 1) that Portland's focus on prejudice dimmed during the war years, 2) that the community was a confluence of humanity, 3) that the design of the site and the housing was shaped by a convergence of New Deal innovations in design construction technologies and electrification and 4) that there was a willingness to sacrifice creature comforts during the war years. Guild's Lake Courts as a residential community under went three rapid evolutions prior to its demolition in 1951, a wartime housing operation 1942-1945, affordable housing 1945-1948, and a haven for Vanport Refugees June 1948-1950. Guild's Lake Courts history has been overlooked but it offers insights into the possible fate of the residents of Vanport City had the community not been flooded in 1948. The story of Guild's Lake Courts is a counterpoint story to Vanport City the largest of the three defense housing projects in Oregon that admitted African-Americans during the war years. Close

• 69. [Article] A Novel Approach to Flow Estimation in Tidal Rivers

  Reliable estimation of river discharge to the ocean from large tidal rivers is vital for water resources management and climate analyses. Due to the difficulties inherent in measuring tidal-river discharge, ...

  Citation × Citation Citation Abstract Copy Title: A Novel Approach to Flow Estimation in Tidal Rivers Author: Moftakhari Rostamkhani, Hamed, Jay, David A, Talke, Stefan A., Kukulka, Tobias, Bromirski, Peter D. Year: 2013 Reliable estimation of river discharge to the ocean from large tidal rivers is vital for water resources management and climate analyses. Due to the difficulties inherent in measuring tidal-river discharge, flow records are often limited in length and/or quality and tidal records often predate discharge records. Tidal theory indicates that tides and river discharge interact through quadratic bed friction, which diminishes and distorts the tidal wave as discharge increases. We use this phenomenon to develop a method of estimating river discharge for time periods with tidal data but no flow record. Employing sequential 32 day harmonic analyses of tidal properties, we calibrate San Francisco (SF), CA tide data to the Sacramento River delta outflow index from 1930 to 1990, and use the resulting relationship to hindcast river flow from 1858 to 1929. The M2 admittance (a ratio of the observed M2 tidal constituent to its astronomical forcing) best reproduces high flows, while low-flow periods are better represented by amplitude ratios based on higher harmonics (e.g.). Results show that the annual inflow to SF Bay is now 30% less than before 1900 and confirm that the flood of January 1862 was the largest since 1858. Title: A Novel Approach to Flow Estimation in Tidal Rivers Author: Moftakhari Rostamkhani, Hamed, Jay, David A, Talke, Stefan A., Kukulka, Tobias, Bromirski, Peter D. Year: 2013 Reliable estimation of river discharge to the ocean from large tidal rivers is vital for water resources management and climate analyses. Due to the difficulties inherent in measuring tidal-river discharge, flow records are often limited in length and/or quality and tidal records often predate discharge records. Tidal theory indicates that tides and river discharge interact through quadratic bed friction, which diminishes and distorts the tidal wave as discharge increases. We use this phenomenon to develop a method of estimating river discharge for time periods with tidal data but no flow record. Employing sequential 32 day harmonic analyses of tidal properties, we calibrate San Francisco (SF), CA tide data to the Sacramento River delta outflow index from 1930 to 1990, and use the resulting relationship to hindcast river flow from 1858 to 1929. The M2 admittance (a ratio of the observed M2 tidal constituent to its astronomical forcing) best reproduces high flows, while low-flow periods are better represented by amplitude ratios based on higher harmonics (e.g.). Results show that the annual inflow to SF Bay is now 30% less than before 1900 and confirm that the flood of January 1862 was the largest since 1858. Close

• 70. [Article] Archaeological Investigations at 45CL1 Cathlapotle (1991-1996) , Ridgefield National Wildlife Refuge Clark County, Washington A Preliminary Report

  Archaeological investigations at site 45CL1, Clark County, Washington, demonstrate that the locality is a very large (c 1.5ha), deeply stratified (2-4m) town site with an occupation spanning at least 1000 ...

  Citation × Citation Citation Abstract Copy Title: Archaeological Investigations at 45CL1 Cathlapotle (1991-1996) , Ridgefield National Wildlife Refuge Clark County, Washington A Preliminary Report Author: Ames, Kenneth M., Smith, Cameron M., Cornett, William L., Sobel, Elizabeth A., Hamilton, Stephen C., Wolf, John, Raetz, Doria, U.S. Fish and Wildlife Service. Region 1, Portland State University. Department of Anthropology Year: 1999 Archaeological investigations at site 45CL1, Clark County, Washington, demonstrate that the locality is a very large (c 1.5ha), deeply stratified (2-4m) town site with an occupation spanning at least 1000 years (c. AD 1000 to 1840). Six large, complex depressions have been mapped. Test excavations show that these depressions represent the semisubterranean portions of residential structures, probably large plankhouses of the type common on the Lower Columbia River and the Northwest Coast in aboriginal times. The depressions may represent as many as 11 such dwellings. A seventh depression is deeply buried beneath midden deposits. The cultural deposits contain very high densities of artifacts, ecofacts (including both faunal and floral remains), debris and features. The site is near the Columbia River on a very active flood plain, resulting in site stratigraphy produced by a combination of active cultural and alluvial depositional processes. Site 45CL1, given its location and size, is the best candidate to be the site of Cathlapotle, a Middle Chinookan town visited by Lewis and Clark in 1806, as well as by other early Europeans in the area. The site is extraordinarily well preserved, having undergone only minor alterations since its abandonment, probably in the third or fourth decade of the 19th century AD. Title: Archaeological Investigations at 45CL1 Cathlapotle (1991-1996) , Ridgefield National Wildlife Refuge Clark County, Washington A Preliminary Report Author: Ames, Kenneth M., Smith, Cameron M., Cornett, William L., Sobel, Elizabeth A., Hamilton, Stephen C., Wolf, John, Raetz, Doria, U.S. Fish and Wildlife Service. Region 1, Portland State University. Department of Anthropology Year: 1999 Archaeological investigations at site 45CL1, Clark County, Washington, demonstrate that the locality is a very large (c 1.5ha), deeply stratified (2-4m) town site with an occupation spanning at least 1000 years (c. AD 1000 to 1840). Six large, complex depressions have been mapped. Test excavations show that these depressions represent the semisubterranean portions of residential structures, probably large plankhouses of the type common on the Lower Columbia River and the Northwest Coast in aboriginal times. The depressions may represent as many as 11 such dwellings. A seventh depression is deeply buried beneath midden deposits. The cultural deposits contain very high densities of artifacts, ecofacts (including both faunal and floral remains), debris and features. The site is near the Columbia River on a very active flood plain, resulting in site stratigraphy produced by a combination of active cultural and alluvial depositional processes. Site 45CL1, given its location and size, is the best candidate to be the site of Cathlapotle, a Middle Chinookan town visited by Lewis and Clark in 1806, as well as by other early Europeans in the area. The site is extraordinarily well preserved, having undergone only minor alterations since its abandonment, probably in the third or fourth decade of the 19th century AD. Close

• 71. [Article] Interfacial Mixing in a Highly Stratified Estuary: 1. Characteristics of Mixing

  This article is Part I of a set of papers addressing mixing in a highly stratified estuary. Measurements of interfacial turbulence were made in Columbia River estuary under conditions of moderate river ...

  Citation × Citation Citation Abstract Copy Title: Interfacial Mixing in a Highly Stratified Estuary: 1. Characteristics of Mixing Author: Kay, David J., Jay, David A. Year: 2003 This article is Part I of a set of papers addressing mixing in a highly stratified estuary. Measurements of interfacial turbulence were made in Columbia River estuary under conditions of moderate river flow and neap tides. A flux correlation method was used to determine buoyancy fluxes, and fits to theoretical velocity and temperature variance spectra were used to measure turbulent kinetic and potential energy dissipation rates. At the measurement site in the interior of the estuary, mixing along the top of the salt wedge is found to occur only on ebb, during periods when the internal Froude number is supercritical. The wedge cannot, therefore, be in a quasiequilibrium state, and vertical mixing plays a dominant role in its ebb retreat. The turbulent Froude number FrT, which represents the ratio of effects of shear and stratification on the mixing, was found to be close to FrTap 1 during mixing episodes. This suggests an interplay between shear and buoyancy effects that corresponds to a condition of maximum mixing efficiency Gamma. Gamma is measured using both direct calculations of the buoyancy and dissipation terms in the turbulent kinetic energy (TKE) balance (this estimate of Gamma is referred to as Gammad), and by estimating the buoyancy term B by its relationship to chiT, the dissipation of temperature variance (this estimate of Gamma is referred to as Gammad). Averages over several mixing events give Gamma0ap 0.22 and Gammadap 0.36. Sources of bias in these measurements result from (1) approximations to the full TKE and available potential energy (APE) balances, (2) empirical constants used in fits of measured spectra in inertial subranges, (3) frame motion, and (4) high-pass filtering. The sign of the biases suggest that 0.22 < Gamma < 0.36. Flood-ebb asymmetry in mixing also results in a time dependent force balance (discussed further by Kay and Jay, 2003). This asymmetry is analyzed using a new method to determine profiles of the momentum balance during ebb mixing events. Title: Interfacial Mixing in a Highly Stratified Estuary: 1. Characteristics of Mixing Author: Kay, David J., Jay, David A. Year: 2003 This article is Part I of a set of papers addressing mixing in a highly stratified estuary. Measurements of interfacial turbulence were made in Columbia River estuary under conditions of moderate river flow and neap tides. A flux correlation method was used to determine buoyancy fluxes, and fits to theoretical velocity and temperature variance spectra were used to measure turbulent kinetic and potential energy dissipation rates. At the measurement site in the interior of the estuary, mixing along the top of the salt wedge is found to occur only on ebb, during periods when the internal Froude number is supercritical. The wedge cannot, therefore, be in a quasiequilibrium state, and vertical mixing plays a dominant role in its ebb retreat. The turbulent Froude number FrT, which represents the ratio of effects of shear and stratification on the mixing, was found to be close to FrTap 1 during mixing episodes. This suggests an interplay between shear and buoyancy effects that corresponds to a condition of maximum mixing efficiency Gamma. Gamma is measured using both direct calculations of the buoyancy and dissipation terms in the turbulent kinetic energy (TKE) balance (this estimate of Gamma is referred to as Gammad), and by estimating the buoyancy term B by its relationship to chiT, the dissipation of temperature variance (this estimate of Gamma is referred to as Gammad). Averages over several mixing events give Gamma0ap 0.22 and Gammadap 0.36. Sources of bias in these measurements result from (1) approximations to the full TKE and available potential energy (APE) balances, (2) empirical constants used in fits of measured spectra in inertial subranges, (3) frame motion, and (4) high-pass filtering. The sign of the biases suggest that 0.22 < Gamma < 0.36. Flood-ebb asymmetry in mixing also results in a time dependent force balance (discussed further by Kay and Jay, 2003). This asymmetry is analyzed using a new method to determine profiles of the momentum balance during ebb mixing events. Close

• 72. [Article] Impacts of Columbia River Discharge on Salmonid Habitat: 2. Changes in Shallow-Water Habitat

  This is the second part of an investigation that analyzes human alteration of shallow-water habitat (SWH) available to juvenile salmonids in the tidal Lower Columbia River. Part 2 develops a one-dimensional, ...

  Citation × Citation Citation Abstract Copy Title: Impacts of Columbia River Discharge on Salmonid Habitat: 2. Changes in Shallow-Water Habitat Author: Jay, David A., Kukulka, Tobias Year: 2003 This is the second part of an investigation that analyzes human alteration of shallow-water habitat (SWH) available to juvenile salmonids in the tidal Lower Columbia River. Part 2 develops a one-dimensional, subtidal river stage model that explains ~90% of the stage variance in the tidal river. This model and the tidal model developed in part 1 (Kukulka and Jay, 2003) uncouple the nonlinear interaction of river tides and river stage by referring both to external forcing by river discharge, ocean tides, and atmospheric pressure. Applying the two models, daily high-water levels were predicted for a reach from rkm-50 to rkm-90 during 1974 to 1998, the period of contemporary management. Predicted water levels were related to the bathymetry and topography to determine the changes in shallow-water habitat area (SWHA) caused by flood control dikes and altered flow management. Model results suggest that diking and a >40% reduction of peak flows have reduced SWHA by ~62% during the crucial spring freshet period during which juvenile salmon use of SWHA is maximal. Taken individually, diking and flow cycle alteration reduced spring freshet SWHA by 52% and 29%, respectively. SWHA has been both displaced to lower elevations and modified in its character because tidal range has increased. Our models of these processes are economical for the very long simulations (seasons to centuries) needed to understand historic changes and climate impacts on SWH. Through analysis of the nonlinear processes controlling surface elevation in a tidal river, we have identified some of the mechanisms that link freshwater discharge to SWH and salmonid survival. Title: Impacts of Columbia River Discharge on Salmonid Habitat: 2. Changes in Shallow-Water Habitat Author: Jay, David A., Kukulka, Tobias Year: 2003 This is the second part of an investigation that analyzes human alteration of shallow-water habitat (SWH) available to juvenile salmonids in the tidal Lower Columbia River. Part 2 develops a one-dimensional, subtidal river stage model that explains ~90% of the stage variance in the tidal river. This model and the tidal model developed in part 1 (Kukulka and Jay, 2003) uncouple the nonlinear interaction of river tides and river stage by referring both to external forcing by river discharge, ocean tides, and atmospheric pressure. Applying the two models, daily high-water levels were predicted for a reach from rkm-50 to rkm-90 during 1974 to 1998, the period of contemporary management. Predicted water levels were related to the bathymetry and topography to determine the changes in shallow-water habitat area (SWHA) caused by flood control dikes and altered flow management. Model results suggest that diking and a >40% reduction of peak flows have reduced SWHA by ~62% during the crucial spring freshet period during which juvenile salmon use of SWHA is maximal. Taken individually, diking and flow cycle alteration reduced spring freshet SWHA by 52% and 29%, respectively. SWHA has been both displaced to lower elevations and modified in its character because tidal range has increased. Our models of these processes are economical for the very long simulations (seasons to centuries) needed to understand historic changes and climate impacts on SWH. Through analysis of the nonlinear processes controlling surface elevation in a tidal river, we have identified some of the mechanisms that link freshwater discharge to SWH and salmonid survival. Close

• 73. [Article] Hydrologic Remote Sensing and Land Surface Data Assimilation

  Accurate, reliable and skillful forecasting of key environmental variables such as soil moisture and snow are of paramount importance due to their strong influence on many water resources applications ...

  Citation × Citation Citation Abstract Copy Title: Hydrologic Remote Sensing and Land Surface Data Assimilation Author: Moradkhani, Hamid Year: 2008 Accurate, reliable and skillful forecasting of key environmental variables such as soil moisture and snow are of paramount importance due to their strong influence on many water resources applications including flood control, agricultural production and effective water resources management which collectively control the behavior of the climate system. Soil moisture is a key state variable in land surface?atmosphere interactions affecting surface energy fluxes, runoff and the radiation balance. Snow processes also have a large influence on land-atmosphere energy exchanges due to snow high albedo, low thermal conductivity and considerable spatial and temporal variability resulting in the dramatic change on surface and ground temperature. Measurement of these two variables is possible through variety of methods using ground-based and remote sensing procedures. Remote sensing, however, holds great promise for soil moisture and snow measurements which have considerable spatial and temporal variability. Merging these measurements with hydrologic model outputs in a systematic and effective way results in an improvement of land surface model prediction. Data Assimilation provides a mechanism to combine these two sources of estimation. Much success has been attained in recent years in using data from passive microwave sensors and assimilating them into the models. This paper provides an overview of the remote sensing measurement techniques for soil moisture and snow data and describes the advances in data assimilation techniques through the ensemble filtering, mainly Ensemble Kalman filter (EnKF) and Particle filter (PF), for improving the model prediction and reducing the uncertainties involved in prediction process. It is believed that PF provides a complete representation of the probability distribution of state variables of interests (according to sequential Bayes law) and could be a strong alternative to EnKF which is subject to some limitations including the linear updating rule and assumption of jointly normal distribution of errors in state variables and observation. Title: Hydrologic Remote Sensing and Land Surface Data Assimilation Author: Moradkhani, Hamid Year: 2008 Accurate, reliable and skillful forecasting of key environmental variables such as soil moisture and snow are of paramount importance due to their strong influence on many water resources applications including flood control, agricultural production and effective water resources management which collectively control the behavior of the climate system. Soil moisture is a key state variable in land surface?atmosphere interactions affecting surface energy fluxes, runoff and the radiation balance. Snow processes also have a large influence on land-atmosphere energy exchanges due to snow high albedo, low thermal conductivity and considerable spatial and temporal variability resulting in the dramatic change on surface and ground temperature. Measurement of these two variables is possible through variety of methods using ground-based and remote sensing procedures. Remote sensing, however, holds great promise for soil moisture and snow measurements which have considerable spatial and temporal variability. Merging these measurements with hydrologic model outputs in a systematic and effective way results in an improvement of land surface model prediction. Data Assimilation provides a mechanism to combine these two sources of estimation. Much success has been attained in recent years in using data from passive microwave sensors and assimilating them into the models. This paper provides an overview of the remote sensing measurement techniques for soil moisture and snow data and describes the advances in data assimilation techniques through the ensemble filtering, mainly Ensemble Kalman filter (EnKF) and Particle filter (PF), for improving the model prediction and reducing the uncertainties involved in prediction process. It is believed that PF provides a complete representation of the probability distribution of state variables of interests (according to sequential Bayes law) and could be a strong alternative to EnKF which is subject to some limitations including the linear updating rule and assumption of jointly normal distribution of errors in state variables and observation. Close

• 74. [Article] Estimation of Historic Flows and Sediment Loads to San Francisco Bay, 1849 – 2011

  River flow and sediment transport in estuaries influence morphological development over decadal and century time scales, but hydrological and sedimentological records are typically too short to adequately ...

  Citation × Citation Citation Abstract Copy Title: Estimation of Historic Flows and Sediment Loads to San Francisco Bay, 1849 – 2011 Author: Moftakhari Rostamkhani, Hamed, Jay, David A., Talke, Stefan A., Schoellhamer, David H. Year: 2015 River flow and sediment transport in estuaries influence morphological development over decadal and century time scales, but hydrological and sedimentological records are typically too short to adequately characterize long-term trends. In this study, we recover archival records and apply a rating curve approach to develop the first instrumental estimates of daily delta inflow and sediment loads to San Francisco Bay (1849 – 1929). The total sediment load is constrained using sedimentation/erosion estimated from bathymetric survey data to produce continuous daily sediment transport estimates from 1849 to 1955, the time period prior to sediment load measurements. We estimate that ~55% (45 – 75%) of the ~1500±400 million tons (Mt) of sediment delivered to the estuary between 1849 and 2011 was the result of anthropogenic alteration in the watershed that increased sediment supply. Also, the seasonal timing of sediment flux events has shifted because significant spring-melt floods have decreased, causing estimated springtime transport (April 1st to June 30th) to decrease from ~25% to ~15% of the annual total. By contrast, wintertime sediment loads (December 1st to March 31st) have increased from ~70% to ~80%. A ~35% reduction of annual flow since the 19th century along with decreased sediment supply has resulted in a ~50% reduction in annual sediment delivery. The methods developed in this study can be applied to other systems for which unanalyzed historic data exist. Title: Estimation of Historic Flows and Sediment Loads to San Francisco Bay, 1849 – 2011 Author: Moftakhari Rostamkhani, Hamed, Jay, David A., Talke, Stefan A., Schoellhamer, David H. Year: 2015 River flow and sediment transport in estuaries influence morphological development over decadal and century time scales, but hydrological and sedimentological records are typically too short to adequately characterize long-term trends. In this study, we recover archival records and apply a rating curve approach to develop the first instrumental estimates of daily delta inflow and sediment loads to San Francisco Bay (1849 – 1929). The total sediment load is constrained using sedimentation/erosion estimated from bathymetric survey data to produce continuous daily sediment transport estimates from 1849 to 1955, the time period prior to sediment load measurements. We estimate that ~55% (45 – 75%) of the ~1500±400 million tons (Mt) of sediment delivered to the estuary between 1849 and 2011 was the result of anthropogenic alteration in the watershed that increased sediment supply. Also, the seasonal timing of sediment flux events has shifted because significant spring-melt floods have decreased, causing estimated springtime transport (April 1st to June 30th) to decrease from ~25% to ~15% of the annual total. By contrast, wintertime sediment loads (December 1st to March 31st) have increased from ~70% to ~80%. A ~35% reduction of annual flow since the 19th century along with decreased sediment supply has resulted in a ~50% reduction in annual sediment delivery. The methods developed in this study can be applied to other systems for which unanalyzed historic data exist. Close

• 75. [Article] Investigating Future Variation of Extreme Precipitation Events over the Willamette River Basin Using Dynamically Downscaled Climate Scenarios

  One important aspect related to the management of water resources under future climate variation is the occurrence of extreme precipitation events. In order to prepare for extreme events, namely floods ...

  Citation × Citation Citation Abstract Copy Title: Investigating Future Variation of Extreme Precipitation Events over the Willamette River Basin Using Dynamically Downscaled Climate Scenarios Author: Halmstad, Andrew Jason Year: 2011 One important aspect related to the management of water resources under future climate variation is the occurrence of extreme precipitation events. In order to prepare for extreme events, namely floods and droughts, it is important to understand how future climate variability will influence the occurrence of such events. Recent advancements in regional climate modeling efforts provide additional resources for investigating the occurrence of extreme events at scales that are appropriate for regional hydrologic modeling. This study utilizes data from three Regional Climate Models (RCMs), each driven by the same General Circulation Model (GCM) as well as a reanalysis dataset, all of which was made available by the North American Regional Climate Change Assessment Program (NARCCAP). A comparison between observed historical precipitation events and NARCCAP modeled historical conditions over Oregon's Willamette River basin was performed. This comparison is required in order to investigate the reliability of regional climate modeling efforts. Datasets representing future climate signal scenarios, also provided by NARCCAP, were then compared to historical data to provide an estimate of the variability in extreme event occurrence and severity within the basin. Analysis determining magnitudes of two, five, ten and twenty-five year return level estimates, as well as parameters corresponding to a representative Generalized Extreme Value (GEV) distribution, were determined. The results demonstrate the importance of the applied initial/boundary driving conditions, the need for multi-model ensemble analysis due to RCM variability, and the need for further downscaling and bias correction methods to RCM datasets when investigating watershed scale phenomena. Title: Investigating Future Variation of Extreme Precipitation Events over the Willamette River Basin Using Dynamically Downscaled Climate Scenarios Author: Halmstad, Andrew Jason Year: 2011 One important aspect related to the management of water resources under future climate variation is the occurrence of extreme precipitation events. In order to prepare for extreme events, namely floods and droughts, it is important to understand how future climate variability will influence the occurrence of such events. Recent advancements in regional climate modeling efforts provide additional resources for investigating the occurrence of extreme events at scales that are appropriate for regional hydrologic modeling. This study utilizes data from three Regional Climate Models (RCMs), each driven by the same General Circulation Model (GCM) as well as a reanalysis dataset, all of which was made available by the North American Regional Climate Change Assessment Program (NARCCAP). A comparison between observed historical precipitation events and NARCCAP modeled historical conditions over Oregon's Willamette River basin was performed. This comparison is required in order to investigate the reliability of regional climate modeling efforts. Datasets representing future climate signal scenarios, also provided by NARCCAP, were then compared to historical data to provide an estimate of the variability in extreme event occurrence and severity within the basin. Analysis determining magnitudes of two, five, ten and twenty-five year return level estimates, as well as parameters corresponding to a representative Generalized Extreme Value (GEV) distribution, were determined. The results demonstrate the importance of the applied initial/boundary driving conditions, the need for multi-model ensemble analysis due to RCM variability, and the need for further downscaling and bias correction methods to RCM datasets when investigating watershed scale phenomena. Close

• 76. [Article] Landforms along the Lower Columbia River and the Influence of Humans

  River systems, such as the Columbia River in the Pacific Northwest, USA have been influenced by human activities, resulting in changes to the physical processes that drive landform evolution. This work ...

  Citation × Citation Citation Abstract Copy Title: Landforms along the Lower Columbia River and the Influence of Humans Author: Cannon, Charles Matthew Year: 2015 River systems, such as the Columbia River in the Pacific Northwest, USA have been influenced by human activities, resulting in changes to the physical processes that drive landform evolution. This work describes an inventory of landforms along the Columbia River estuary between the Pacific Ocean and Bonneville Dam in Oregon and Washington. Groupings of landforms are assigned to formative process regimes that are used to assess historical changes to floodplain features. The estuary was historically a complex system of channels with a floodplain dominated by extensive tidal wetlands in the lower reaches and backswamp lakes and wetlands in upper reaches. Natural levees flank most channels in the upper reaches, locally including areas of ridge and swale topography and crevasse splays that intrude into backswamps. Other Holocene process regimes affecting floodplain morphology have included volcanogenic deltas, tributary fans, dunes, and landslides. Pre-Holocene landforms are locally prominent and include ancient fluvial deposits and bedrock. Historical changes to streamflow regimes, floodplain isolation by flood-control systems, and direct anthropogenic disturbance have resulted in channel narrowing and limited the amount of floodplain that can be shaped by flowing water. Floodplain isolation has caused relative subsidence of tidal floodplains along much of the lower estuary. Most extant landforms are on trajectories controlled by humans and new landforms are mostly created by humans. Title: Landforms along the Lower Columbia River and the Influence of Humans Author: Cannon, Charles Matthew Year: 2015 River systems, such as the Columbia River in the Pacific Northwest, USA have been influenced by human activities, resulting in changes to the physical processes that drive landform evolution. This work describes an inventory of landforms along the Columbia River estuary between the Pacific Ocean and Bonneville Dam in Oregon and Washington. Groupings of landforms are assigned to formative process regimes that are used to assess historical changes to floodplain features. The estuary was historically a complex system of channels with a floodplain dominated by extensive tidal wetlands in the lower reaches and backswamp lakes and wetlands in upper reaches. Natural levees flank most channels in the upper reaches, locally including areas of ridge and swale topography and crevasse splays that intrude into backswamps. Other Holocene process regimes affecting floodplain morphology have included volcanogenic deltas, tributary fans, dunes, and landslides. Pre-Holocene landforms are locally prominent and include ancient fluvial deposits and bedrock. Historical changes to streamflow regimes, floodplain isolation by flood-control systems, and direct anthropogenic disturbance have resulted in channel narrowing and limited the amount of floodplain that can be shaped by flowing water. Floodplain isolation has caused relative subsidence of tidal floodplains along much of the lower estuary. Most extant landforms are on trajectories controlled by humans and new landforms are mostly created by humans. Close

• 77. [Article] Risk Factors for Pre-Post Monsoon Cholera Epidemics in Bangladesh from 1992-1994

  The primary objective of this thesis is to differentiate between the risk factors for pre-and post-monsoon cholera epidemics in rural Bangladesh by analyzing the complex interaction between select environmental, ...

  Citation × Citation Citation Abstract Copy Title: Risk Factors for Pre-Post Monsoon Cholera Epidemics in Bangladesh from 1992-1994 Author: Robb, Rhonda Rae Year: 2004 The primary objective of this thesis is to differentiate between the risk factors for pre-and post-monsoon cholera epidemics in rural Bangladesh by analyzing the complex interaction between select environmental, cultural/behavioral, and socioeconomic variables over space and time. In rural Bangladesh, cholera epidemics correspond with the annual monsoon: the first, and smallest, occurs between March and June, while the larger cholera peak occurs between September and December. The differences between the spatial and temporal patterns of seasonal cholera are analyzed, and the risk factors are calculated for pre-and post-monsoon cholera epidemics. The theoretical approach that underlies this medical geographical study is disease ecology, which espouses that risk of disease is caused by an interaction between people and their environment. This thesis is structured around a holistic understanding that human-environment interactions are inseparable. In Bangladesh, the monsoon season typically starts between May and June. The 1992 and 1993 cholera peaks occurred just before the monsoon in April and March respectively, while the 1994 cholera peak occurred between April and June. In 1992 and 1993 cholera incidence increased in the post-monsoon period, and peaked in October. The 1994 post-monsoon cholera peak occurred in November. There is a regular temporal pattern to cholera, as the peaks followed a seasonal pattern with the smaller epidemic occurring in the pre-monsoon period and the larger epidemic occurring in the post-monsoon period. This study shows that there are different risks associated with pre-monsoon cholera epidemics and post-monsoon cholera epidemics. The two main risk factors associated with cholera incidence pre-monsoon were bari population (i.e., crowding) and a house located within the flood controlled area. These two variables were even more strongly associated with post-monsoon cholera incidence to a greater degree, along with a number of other variables including water use, sanitation practices, and socioeconomic status. Title: Risk Factors for Pre-Post Monsoon Cholera Epidemics in Bangladesh from 1992-1994 Author: Robb, Rhonda Rae Year: 2004 The primary objective of this thesis is to differentiate between the risk factors for pre-and post-monsoon cholera epidemics in rural Bangladesh by analyzing the complex interaction between select environmental, cultural/behavioral, and socioeconomic variables over space and time. In rural Bangladesh, cholera epidemics correspond with the annual monsoon: the first, and smallest, occurs between March and June, while the larger cholera peak occurs between September and December. The differences between the spatial and temporal patterns of seasonal cholera are analyzed, and the risk factors are calculated for pre-and post-monsoon cholera epidemics. The theoretical approach that underlies this medical geographical study is disease ecology, which espouses that risk of disease is caused by an interaction between people and their environment. This thesis is structured around a holistic understanding that human-environment interactions are inseparable. In Bangladesh, the monsoon season typically starts between May and June. The 1992 and 1993 cholera peaks occurred just before the monsoon in April and March respectively, while the 1994 cholera peak occurred between April and June. In 1992 and 1993 cholera incidence increased in the post-monsoon period, and peaked in October. The 1994 post-monsoon cholera peak occurred in November. There is a regular temporal pattern to cholera, as the peaks followed a seasonal pattern with the smaller epidemic occurring in the pre-monsoon period and the larger epidemic occurring in the post-monsoon period. This study shows that there are different risks associated with pre-monsoon cholera epidemics and post-monsoon cholera epidemics. The two main risk factors associated with cholera incidence pre-monsoon were bari population (i.e., crowding) and a house located within the flood controlled area. These two variables were even more strongly associated with post-monsoon cholera incidence to a greater degree, along with a number of other variables including water use, sanitation practices, and socioeconomic status. Close

• 78. [Article] Decreasing Emissions of Methane from Rice Agriculture

  Methane emissions from rice fields are controlled by several key factors. The most important are the application of organic soil amendments and water management: whether the fields are flooded intermittently ...

  Citation × Citation Citation Abstract Copy Title: Decreasing Emissions of Methane from Rice Agriculture Author: Khalil, M. A. K., Shearer, Martha J. Year: 2006 Methane emissions from rice fields are controlled by several key factors. The most important are the application of organic soil amendments and water management: whether the fields are flooded intermittently or continuously. The total annual emissions from any country or the world are thus affected by the area of rice harvested, and a composite emission factor that takes into account how the various agricultural practices are distributed in terms of fertilizer use and water management, as well as other less important variables. Over decades the area of rice harvested changes but so does the composite emission factor. The product therefore, may change substantially over decadal time scales. We will argue that for China at least, there are downward trends of both area and emission factor leading to a substantial reduction of annual emissions over the last two decades from some 30 Tg/yr to perhaps less than 10 Tg/yr. The changes that cause these reductions would increase nitrous oxide emissions from rice fields as organic fertilizers are replaced with nitrogen based fertilizers. Similar changes are likely to be occurring world-wide. These trends of emissions are probably represented in the observed slowdown of methane trend in the atmosphere and the continuing steady increase of nitrous oxide. Title: Decreasing Emissions of Methane from Rice Agriculture Author: Khalil, M. A. K., Shearer, Martha J. Year: 2006 Methane emissions from rice fields are controlled by several key factors. The most important are the application of organic soil amendments and water management: whether the fields are flooded intermittently or continuously. The total annual emissions from any country or the world are thus affected by the area of rice harvested, and a composite emission factor that takes into account how the various agricultural practices are distributed in terms of fertilizer use and water management, as well as other less important variables. Over decades the area of rice harvested changes but so does the composite emission factor. The product therefore, may change substantially over decadal time scales. We will argue that for China at least, there are downward trends of both area and emission factor leading to a substantial reduction of annual emissions over the last two decades from some 30 Tg/yr to perhaps less than 10 Tg/yr. The changes that cause these reductions would increase nitrous oxide emissions from rice fields as organic fertilizers are replaced with nitrogen based fertilizers. Similar changes are likely to be occurring world-wide. These trends of emissions are probably represented in the observed slowdown of methane trend in the atmosphere and the continuing steady increase of nitrous oxide. Close

• 79. [Article] Impacts of Predicted Global Sea-Level Rise on Oregon Beaches and Tidelands

  Forward by: Phillip Johnson, Executive Director Oregon Shores Conservation Coalition The Oregon Shores Conservation Coalition’s "Coastal Climate Change Adaptation Project" is under development as an experiment ...

  Citation × Citation Citation Abstract Copy Title: Impacts of Predicted Global Sea-Level Rise on Oregon Beaches and Tidelands Author: Peterson, Curt D. Year: 2013 Forward by: Phillip Johnson, Executive Director Oregon Shores Conservation Coalition The Oregon Shores Conservation Coalition’s "Coastal Climate Change Adaptation Project" is under development as an experiment in grassroots organizing for adaptive planning for expected climate change impacts. Oregon Shores is a regional conservation group with a 40-year history of working to protect marine, shoreline, estuarine and other coastal habitats. The organization’s board and staff came to recognize that the likely effects of climate change—rising sea levels, more intensive storm surges, increased erosion, lower-river flooding, among others—would affect every aspect of the group’s work. Consequently, a new program, the Climate Action Program, was created to address the need for long-range adaptive planning to preserve the resilience of communities, both human and natural. Oregon Shores’ premise in developing the Coastal Climate Change Adaptation Project is that for adaptive planning to be meaningful, broad community acceptance and support are necessary. The project is thus designed as a grassroots effort, with the aim of developing broad support before any proposal should be submitted to local governments. Title: Impacts of Predicted Global Sea-Level Rise on Oregon Beaches and Tidelands Author: Peterson, Curt D. Year: 2013 Forward by: Phillip Johnson, Executive Director Oregon Shores Conservation Coalition The Oregon Shores Conservation Coalition’s "Coastal Climate Change Adaptation Project" is under development as an experiment in grassroots organizing for adaptive planning for expected climate change impacts. Oregon Shores is a regional conservation group with a 40-year history of working to protect marine, shoreline, estuarine and other coastal habitats. The organization’s board and staff came to recognize that the likely effects of climate change—rising sea levels, more intensive storm surges, increased erosion, lower-river flooding, among others—would affect every aspect of the group’s work. Consequently, a new program, the Climate Action Program, was created to address the need for long-range adaptive planning to preserve the resilience of communities, both human and natural. Oregon Shores’ premise in developing the Coastal Climate Change Adaptation Project is that for adaptive planning to be meaningful, broad community acceptance and support are necessary. The project is thus designed as a grassroots effort, with the aim of developing broad support before any proposal should be submitted to local governments. Close

• 80. [Article] Probabilistic Tsunami Hazard Assessment at Seaside, Oregon, for Near- and Far-Field Seismic Sources

  The first probabilistic tsunami flooding maps have been developed. The methodology, called probabilistic tsunami hazard assessment (PTHA), integrates tsunami inundation modeling with methods of probabilistic ...

  Citation × Citation Citation Abstract Copy Title: Probabilistic Tsunami Hazard Assessment at Seaside, Oregon, for Near- and Far-Field Seismic Sources Author: González, Frank, Geist, Eric L., Jaffe, Bruce, Kânoğlu, Utku, Mofjeld, Harold O., Synolakis, Costas, Titov, Vasily V., Arcas, Diego Rodriguez, Bellomo, Douglas, Carlton, David, Horning, Thomas, Johnson, Jeff, Newman, Jean, Parsons, Thomas, Peters, Robert, Peterson, Curt D., Priest, George, Venturato, Angie, Weber, Joseph, Wong, Florence L., Yalçıner, Ahmet Year: 2009 The first probabilistic tsunami flooding maps have been developed. The methodology, called probabilistic tsunami hazard assessment (PTHA), integrates tsunami inundation modeling with methods of probabilistic seismic hazard assessment (PSHA). Application of the methodology to Seaside, Oregon, has yielded estimates of the spatial distribution of 100- and 500-year maximum tsunami amplitudes, i.e., amplitudes with 1% and 0.2% annual probability of exceedance. The 100-year tsunami is generated most frequently by far-field sources in the Alaska-Aleutian Subduction Zone and is characterized by maximum amplitudes that do not exceed 4 m, with an inland extent of less than 500 m. In contrast, the 500-year tsunami is dominated by local sources in the Cascadia Subduction Zone and is characterized by maximum amplitudes in excess of 10 m and an inland extent of more than 1 km. The primary sources of uncertainty in these results include those associated with interevent time estimates, modeling of background sea level, and accounting for temporal changes in bathymetry and topography. Nonetheless, PTHA represents an important contribution to tsunami hazard assessment techniques; viewed in the broader context of risk analysis, PTHA provides a method for quantifying estimates of the likelihood and severity of the tsunami hazard, which can then be combined with vulnerability and exposure to yield estimates of tsunami risk. Title: Probabilistic Tsunami Hazard Assessment at Seaside, Oregon, for Near- and Far-Field Seismic Sources Author: González, Frank, Geist, Eric L., Jaffe, Bruce, Kânoğlu, Utku, Mofjeld, Harold O., Synolakis, Costas, Titov, Vasily V., Arcas, Diego Rodriguez, Bellomo, Douglas, Carlton, David, Horning, Thomas, Johnson, Jeff, Newman, Jean, Parsons, Thomas, Peters, Robert, Peterson, Curt D., Priest, George, Venturato, Angie, Weber, Joseph, Wong, Florence L., Yalçıner, Ahmet Year: 2009 The first probabilistic tsunami flooding maps have been developed. The methodology, called probabilistic tsunami hazard assessment (PTHA), integrates tsunami inundation modeling with methods of probabilistic seismic hazard assessment (PSHA). Application of the methodology to Seaside, Oregon, has yielded estimates of the spatial distribution of 100- and 500-year maximum tsunami amplitudes, i.e., amplitudes with 1% and 0.2% annual probability of exceedance. The 100-year tsunami is generated most frequently by far-field sources in the Alaska-Aleutian Subduction Zone and is characterized by maximum amplitudes that do not exceed 4 m, with an inland extent of less than 500 m. In contrast, the 500-year tsunami is dominated by local sources in the Cascadia Subduction Zone and is characterized by maximum amplitudes in excess of 10 m and an inland extent of more than 1 km. The primary sources of uncertainty in these results include those associated with interevent time estimates, modeling of background sea level, and accounting for temporal changes in bathymetry and topography. Nonetheless, PTHA represents an important contribution to tsunami hazard assessment techniques; viewed in the broader context of risk analysis, PTHA provides a method for quantifying estimates of the likelihood and severity of the tsunami hazard, which can then be combined with vulnerability and exposure to yield estimates of tsunami risk. Close

• 81. [Article] Effects of Production and Oxidation Processes on Methane Emissions from Rice Fields

  The emission of methane from rice fields is the difference between the amount produced in the anaerobic zone below the soil and the amount oxidized in the root zone. Plants can also contribute to methane ...

  Citation × Citation Citation Abstract Copy Title: Effects of Production and Oxidation Processes on Methane Emissions from Rice Fields Author: Khalil, M. A. K., Rasmussen, R. A., Shearer, Martha J. Year: 1998 The emission of methane from rice fields is the difference between the amount produced in the anaerobic zone below the soil and the amount oxidized in the root zone. Plants can also contribute to methane production by exuding organic compounds that may be utilized by methanogenic bacteria. We measured methane emissions from rice fields at Tu Zu in China between 1988 and 1994, which gave average emissions of about 30 mg m⁻² h⁻¹. We estimate that 45-60% of the methane produced was oxidized before reaching the atmosphere; and root exudates may have contributed of the order of 10% of the methane that was produced. The fraction of methane oxidized is low compared to experimental studies at other locations (60-85%). At Tu Zu, methane production is enhanced by continuously flooded fields and the use of large amounts of organic fertilizers; in addition, the lower oxidation rate may also contribute to the higher methane emissions observed compared to other locations. In the past, most of the attention has been devoted to the factors that affect methane production and transport, but it seems that the factors that affect methane oxidation are equally important in determining the flux, if not more so. The comparison of methane fluxes observed at different locations and the extrapolation of field measurements to accurately estimate global emissions will require a better understanding of the rate of methane oxidation in the soils and the factors that control it. Title: Effects of Production and Oxidation Processes on Methane Emissions from Rice Fields Author: Khalil, M. A. K., Rasmussen, R. A., Shearer, Martha J. Year: 1998 The emission of methane from rice fields is the difference between the amount produced in the anaerobic zone below the soil and the amount oxidized in the root zone. Plants can also contribute to methane production by exuding organic compounds that may be utilized by methanogenic bacteria. We measured methane emissions from rice fields at Tu Zu in China between 1988 and 1994, which gave average emissions of about 30 mg m⁻² h⁻¹. We estimate that 45-60% of the methane produced was oxidized before reaching the atmosphere; and root exudates may have contributed of the order of 10% of the methane that was produced. The fraction of methane oxidized is low compared to experimental studies at other locations (60-85%). At Tu Zu, methane production is enhanced by continuously flooded fields and the use of large amounts of organic fertilizers; in addition, the lower oxidation rate may also contribute to the higher methane emissions observed compared to other locations. In the past, most of the attention has been devoted to the factors that affect methane production and transport, but it seems that the factors that affect methane oxidation are equally important in determining the flux, if not more so. The comparison of methane fluxes observed at different locations and the extrapolation of field measurements to accurately estimate global emissions will require a better understanding of the rate of methane oxidation in the soils and the factors that control it. Close

• 82. [Article] Measurements of Methane Emissions from Rice Fields in China

  Rice fields have always been regarded as one of the largest anthropogenic sources of atmospheric methane. Here we report the results of a 7-year study of methane emissions from rice fields in the Sichuan ...

  Citation × Citation Citation Abstract Copy Title: Measurements of Methane Emissions from Rice Fields in China Author: Khalil, M. A. K., Rasmussen, R. A., Shearer, Martha J., Dalluge, R. W., Ren, Lixin, Duan, Chang-Lin Year: 1998 Rice fields have always been regarded as one of the largest anthropogenic sources of atmospheric methane. Here we report the results of a 7-year study of methane emissions from rice fields in the Sichuan Province of China. In this region, there is one crop of rice per year, the fields are continuously flooded from transplanting to harvest, and there is heavy use of organic fertilizers. Emissions over the entire growing season were measured from each of up to 24 plots. Environmental variables were measured and relevant supporting data on the agricultural practices were recorded. The fields were studied under prevailing agricultural practices of the local farmers. The results represent emissions under standard agricultural practices and the year to year variability of climate, fertilizers, available irrigation water, and cultivars. Based on some 5000 flux measurements, the average emission rates between 1988 and 1994 were 30 mg/m²/h for a growing season of between 100 and 120 days. This emission rate is comparable to other published data from similar rice fields but somewhat on the high side of the range. There were no systematic trends of emissions during the 7 years of our experiment, but there was substantial year to year variability. The data have been subjected to exhaustive analyses for validity, accuracy, and reliability. From this, a high-quality, spatially averaged data set has been constructed representing average emissions from the rice fields for each day when measurements were taken. We describe here the main observational results and document the spatial and temporal variability observed on timescales ranging from a day to several years and on spatial scales ranging from 0.5 m² to 16 m². Title: Measurements of Methane Emissions from Rice Fields in China Author: Khalil, M. A. K., Rasmussen, R. A., Shearer, Martha J., Dalluge, R. W., Ren, Lixin, Duan, Chang-Lin Year: 1998 Rice fields have always been regarded as one of the largest anthropogenic sources of atmospheric methane. Here we report the results of a 7-year study of methane emissions from rice fields in the Sichuan Province of China. In this region, there is one crop of rice per year, the fields are continuously flooded from transplanting to harvest, and there is heavy use of organic fertilizers. Emissions over the entire growing season were measured from each of up to 24 plots. Environmental variables were measured and relevant supporting data on the agricultural practices were recorded. The fields were studied under prevailing agricultural practices of the local farmers. The results represent emissions under standard agricultural practices and the year to year variability of climate, fertilizers, available irrigation water, and cultivars. Based on some 5000 flux measurements, the average emission rates between 1988 and 1994 were 30 mg/m²/h for a growing season of between 100 and 120 days. This emission rate is comparable to other published data from similar rice fields but somewhat on the high side of the range. There were no systematic trends of emissions during the 7 years of our experiment, but there was substantial year to year variability. The data have been subjected to exhaustive analyses for validity, accuracy, and reliability. From this, a high-quality, spatially averaged data set has been constructed representing average emissions from the rice fields for each day when measurements were taken. We describe here the main observational results and document the spatial and temporal variability observed on timescales ranging from a day to several years and on spatial scales ranging from 0.5 m² to 16 m². Close

• 83. [Article] High-Resolution Ground-Penetrating Radar Profiles of Perennial Lake Ice in the McMurdo Dry Valleys, Antarctica: Horizon Attributes, Unconformities, and Subbottom

  Ground-penetrating radar (GPR) is not commonly used to study lake ice, and in general, the ground-based use of radar frequencies greater than 500 MHz in cryosphere geophysics is rare, due to a general ...

  Citation × Citation Citation Abstract Copy Title: High-Resolution Ground-Penetrating Radar Profiles of Perennial Lake Ice in the McMurdo Dry Valleys, Antarctica: Horizon Attributes, Unconformities, and Subbottom Author: Dugan, Hilary A., Arcone, Steven A., Obryk, Maciej K., Doran, Peter T. Year: 2016 Ground-penetrating radar (GPR) is not commonly used to study lake ice, and in general, the ground-based use of radar frequencies greater than 500 MHz in cryosphere geophysics is rare, due to a general interest in deeper stratigraphy and the difficulty of extensive profiling over rough snow surfaces. Our goal was to find further information on the origin of the deposition and formation of intra-ice layers, bottom topography, and subbottom deposits using GPR with pulses centered near 850 MHz on two permanently ice-covered lakes in the Mc- Murdo Dry Valleys, Antarctica. The profiles were obtained using a one-person sled operation over Lake Bonney, which is typical of lakes in the region, having an ice thickness that ranges between 3 and 5 m, and Lake Vida, where the maximum ice depth is at least 27 m. Lake Bonney exhibits a semicontinuous sediment horizon at approximately a 2-m depth and several minor horizons. In contrast, Lake Vida contains unconformably eroded and folded continuous reflection horizons, packages of minor horizons between major horizons, evidence of incised fluvial deposition along the bottom, and subbottom penetration of at least 4.5 m in some areas. Where the ice thickness is less than 20 m, the lake is frozen to the bottom. Most horizon waveform phase attributes indicate relatively lower permittivity than in the surrounding matrix. Consequently, we interpreted these strata to be caused by layers of pure ice embedded within a salty and dirty ice matrix, which were formed during minor flooding. These findings supported previous conclusions that Lake Vida ice formed from surface runoff in combination with periods of ablation. Title: High-Resolution Ground-Penetrating Radar Profiles of Perennial Lake Ice in the McMurdo Dry Valleys, Antarctica: Horizon Attributes, Unconformities, and Subbottom Author: Dugan, Hilary A., Arcone, Steven A., Obryk, Maciej K., Doran, Peter T. Year: 2016 Ground-penetrating radar (GPR) is not commonly used to study lake ice, and in general, the ground-based use of radar frequencies greater than 500 MHz in cryosphere geophysics is rare, due to a general interest in deeper stratigraphy and the difficulty of extensive profiling over rough snow surfaces. Our goal was to find further information on the origin of the deposition and formation of intra-ice layers, bottom topography, and subbottom deposits using GPR with pulses centered near 850 MHz on two permanently ice-covered lakes in the Mc- Murdo Dry Valleys, Antarctica. The profiles were obtained using a one-person sled operation over Lake Bonney, which is typical of lakes in the region, having an ice thickness that ranges between 3 and 5 m, and Lake Vida, where the maximum ice depth is at least 27 m. Lake Bonney exhibits a semicontinuous sediment horizon at approximately a 2-m depth and several minor horizons. In contrast, Lake Vida contains unconformably eroded and folded continuous reflection horizons, packages of minor horizons between major horizons, evidence of incised fluvial deposition along the bottom, and subbottom penetration of at least 4.5 m in some areas. Where the ice thickness is less than 20 m, the lake is frozen to the bottom. Most horizon waveform phase attributes indicate relatively lower permittivity than in the surrounding matrix. Consequently, we interpreted these strata to be caused by layers of pure ice embedded within a salty and dirty ice matrix, which were formed during minor flooding. These findings supported previous conclusions that Lake Vida ice formed from surface runoff in combination with periods of ablation. Close

• 84. [Article] Survey of Aquatic Plants in Corps of Engineers Reservoirs

  A survey of aquatic plants in a selected Corps of Engineers reservoirs in Oregon was conducted. Cottage Grove, Dorena, Fern Ridge, Dexter and Willow Creek Reservoirs contained abundant aquatic plants. ...

  Citation × Citation Citation Abstract Copy Title: Survey of Aquatic Plants in Corps of Engineers Reservoirs Author: Walker, Kimberly D., Sytsma, Mark D. Year: 2000 A survey of aquatic plants in a selected Corps of Engineers reservoirs in Oregon was conducted. Cottage Grove, Dorena, Fern Ridge, Dexter and Willow Creek Reservoirs contained abundant aquatic plants. Potamogeton pectinatus and Potamogeton epihydrous were the most common native plant species. Myriophyllum aquaticum and Potamogeton crispus were the most widespread nonnative plants. Species richness in the reservoirs was correlated with trophic status and basin morphology. Shallow reservoirs that included extensive areas of nutrient-rich sediments that were historic flood plain soils supported the greatest biomass and number of species. Mesotrophic reservoirs had lower species diversity. Oligotrophic reservoirs with steep basin morphology, nutrient-poor sediments, and large water level fluctuation did not support aquatic vascular plant populations. An aquatic plant management program should be developed for the reservoirs. The program should focus on preventing introduction and spread of invasive aquatic plants and on rapid response procedures for new infestations. Those reservoirs that currently support aquatic macrophyte communities may be most susceptible to invasion and rapid spread of new introductions, however, even reservoirs that are currently free of aquatic plants may be invaded. Early detection is critical to effective implementation of rapid response procedures for invasive aquatic plant control. Annual survey of the most productive reservoirs is recommended to document introduction of new species. Plant community composition changes during the growing season, and multiple surveys during the growing season are preferred over one-time visits. Management of established populations of invasive species in the reservoirs will be difficult. Where invasive plant abundance is limited in area and number management activities may be implemented to slow dispersal and perhaps eradicate the plants. Integrated pest management procedures should be followed to ensure effective and economical aquatic plant control. Title: Survey of Aquatic Plants in Corps of Engineers Reservoirs Author: Walker, Kimberly D., Sytsma, Mark D. Year: 2000 A survey of aquatic plants in a selected Corps of Engineers reservoirs in Oregon was conducted. Cottage Grove, Dorena, Fern Ridge, Dexter and Willow Creek Reservoirs contained abundant aquatic plants. Potamogeton pectinatus and Potamogeton epihydrous were the most common native plant species. Myriophyllum aquaticum and Potamogeton crispus were the most widespread nonnative plants. Species richness in the reservoirs was correlated with trophic status and basin morphology. Shallow reservoirs that included extensive areas of nutrient-rich sediments that were historic flood plain soils supported the greatest biomass and number of species. Mesotrophic reservoirs had lower species diversity. Oligotrophic reservoirs with steep basin morphology, nutrient-poor sediments, and large water level fluctuation did not support aquatic vascular plant populations. An aquatic plant management program should be developed for the reservoirs. The program should focus on preventing introduction and spread of invasive aquatic plants and on rapid response procedures for new infestations. Those reservoirs that currently support aquatic macrophyte communities may be most susceptible to invasion and rapid spread of new introductions, however, even reservoirs that are currently free of aquatic plants may be invaded. Early detection is critical to effective implementation of rapid response procedures for invasive aquatic plant control. Annual survey of the most productive reservoirs is recommended to document introduction of new species. Plant community composition changes during the growing season, and multiple surveys during the growing season are preferred over one-time visits. Management of established populations of invasive species in the reservoirs will be difficult. Where invasive plant abundance is limited in area and number management activities may be implemented to slow dispersal and perhaps eradicate the plants. Integrated pest management procedures should be followed to ensure effective and economical aquatic plant control. Close

• 85. [Article] Temporal and Crustal Effects on Differentiation of Tholeiite to Calcalkaline and Ferro-trachytic Suites, High Lava Plains, Oregon, USA

  Strongly bimodal, basalt-rhyolite volcanism of the High Lava Plains Province of Oregon followed the Middle Miocene flood basalts of the Pacific Northwest and extends to recent time. During the 8 m.y. of ...

  Citation × Citation Citation Abstract Copy Title: Temporal and Crustal Effects on Differentiation of Tholeiite to Calcalkaline and Ferro-trachytic Suites, High Lava Plains, Oregon, USA Author: Streck, Martin J., Grunder, Anita L. Year: 2012 Strongly bimodal, basalt-rhyolite volcanism of the High Lava Plains Province of Oregon followed the Middle Miocene flood basalts of the Pacific Northwest and extends to recent time. During the 8 m.y. of volcanism recorded in the central High Lava Plains, in western Harney Basin, three distinct mafic magmatic trends originate from primitive high-alumina olivine tholeiites (HAOT); they are tholeiitic, calcalkaline and ferro-trachytic. Tholeiitic basalts occur throughout the history and their compositions are derived by crystal fractionation while traversing the crust and mixing with evolved mafic magmas. Scavenging of apatite from crustal rocks and minor contamination with felsic melts accounts for P, incompatible element enrichments and increasing tilts of incompatible element patterns with differentiation. The calcalkaline mafic suite occurs in temporal association with abundant silicic volcanism and is the only suite with Fe decreasing with Mg. Calcalkaline compositions are derived from evolved tholeiitic basalt by crystal fractionation coupled with assimilation of felsic crust or crustal melts. The ferro-trachytic suite occurs mainly late, is highly enriched in incompatible element with patterns parallel to tholeiites from which it is derived by protracted fractionation and recharge. The three suites primarily reflect changes in magma flux and crustal interactions in time. High magma flux promotes crustal melting and contamination of tholeiite to make the calcalkaline suite. On the other hand, ferrotrachytic magmas erupted mainly late in the sequence, during magmatic waning and after significant basaltification of the crust. Title: Temporal and Crustal Effects on Differentiation of Tholeiite to Calcalkaline and Ferro-trachytic Suites, High Lava Plains, Oregon, USA Author: Streck, Martin J., Grunder, Anita L. Year: 2012 Strongly bimodal, basalt-rhyolite volcanism of the High Lava Plains Province of Oregon followed the Middle Miocene flood basalts of the Pacific Northwest and extends to recent time. During the 8 m.y. of volcanism recorded in the central High Lava Plains, in western Harney Basin, three distinct mafic magmatic trends originate from primitive high-alumina olivine tholeiites (HAOT); they are tholeiitic, calcalkaline and ferro-trachytic. Tholeiitic basalts occur throughout the history and their compositions are derived by crystal fractionation while traversing the crust and mixing with evolved mafic magmas. Scavenging of apatite from crustal rocks and minor contamination with felsic melts accounts for P, incompatible element enrichments and increasing tilts of incompatible element patterns with differentiation. The calcalkaline mafic suite occurs in temporal association with abundant silicic volcanism and is the only suite with Fe decreasing with Mg. Calcalkaline compositions are derived from evolved tholeiitic basalt by crystal fractionation coupled with assimilation of felsic crust or crustal melts. The ferro-trachytic suite occurs mainly late, is highly enriched in incompatible element with patterns parallel to tholeiites from which it is derived by protracted fractionation and recharge. The three suites primarily reflect changes in magma flux and crustal interactions in time. High magma flux promotes crustal melting and contamination of tholeiite to make the calcalkaline suite. On the other hand, ferrotrachytic magmas erupted mainly late in the sequence, during magmatic waning and after significant basaltification of the crust. Close

• 86. [Article] Phosphorus Export from a Restored Wetland Ecosystem in Response to Natural and Experimental Hydrologic Fluctuations

  Wetland restoration is a commonly used approach to reduce nutrient loading to freshwater and coastal ecosystems, with many wetland restoration efforts occurring in former agricultural fields. Restored ...

  Citation × Citation Citation Abstract Copy Title: Phosphorus Export from a Restored Wetland Ecosystem in Response to Natural and Experimental Hydrologic Fluctuations Author: Ardón, Marcelo, Montanari, Shaena, Morse, Jennifer L., Doyle, Martin W., Bernhardt, Emily S. Year: 2010 Wetland restoration is a commonly used approach to reduce nutrient loading to freshwater and coastal ecosystems, with many wetland restoration efforts occurring in former agricultural fields. Restored wetlands are expected to be effective at retaining or removing both nitrogen and phosphorus (P), yet restoring wetland hydrology to former agricultural fields can lead to the release of legacy fertilizer P. Here, we examined P cycling and export following rewetting of the Timberlake Restoration Project, a 440 ha restored riverine wetland complex in the coastal plain of North Carolina. We also compared P cycling within the restored wetland to two minimally disturbed nearby wetlands and an adjacent active agricultural field. In the restored wetland we observed increased soluble reactive phosphorus (SRP) concentrations following initial flooding, consistent with our expectations that P bound to iron would be released under reducing conditions. SRP concentrations in spring were 2.5 times higher leaving the restored wetland than a forested wetland and an agricultural field. During two large- scale drawdown and rewetting experiments we decreased the water depth by 1 m in ∼10 ha of inundated wetland for 2 weeks, followed by reflooding. Rewetting following experimental drainage had no effect on SRP concentrations in winter, but SRP concentrations did increase when the experiment was repeated during summer. Our best estimates suggest that this restored wetland could release legacy fertilizer P for up to a decade following hydrologic restoration. The time lag between restoration and biogeochemical recovery should be incorporated into management strategies of restored wetlands. Title: Phosphorus Export from a Restored Wetland Ecosystem in Response to Natural and Experimental Hydrologic Fluctuations Author: Ardón, Marcelo, Montanari, Shaena, Morse, Jennifer L., Doyle, Martin W., Bernhardt, Emily S. Year: 2010 Wetland restoration is a commonly used approach to reduce nutrient loading to freshwater and coastal ecosystems, with many wetland restoration efforts occurring in former agricultural fields. Restored wetlands are expected to be effective at retaining or removing both nitrogen and phosphorus (P), yet restoring wetland hydrology to former agricultural fields can lead to the release of legacy fertilizer P. Here, we examined P cycling and export following rewetting of the Timberlake Restoration Project, a 440 ha restored riverine wetland complex in the coastal plain of North Carolina. We also compared P cycling within the restored wetland to two minimally disturbed nearby wetlands and an adjacent active agricultural field. In the restored wetland we observed increased soluble reactive phosphorus (SRP) concentrations following initial flooding, consistent with our expectations that P bound to iron would be released under reducing conditions. SRP concentrations in spring were 2.5 times higher leaving the restored wetland than a forested wetland and an agricultural field. During two large- scale drawdown and rewetting experiments we decreased the water depth by 1 m in ∼10 ha of inundated wetland for 2 weeks, followed by reflooding. Rewetting following experimental drainage had no effect on SRP concentrations in winter, but SRP concentrations did increase when the experiment was repeated during summer. Our best estimates suggest that this restored wetland could release legacy fertilizer P for up to a decade following hydrologic restoration. The time lag between restoration and biogeochemical recovery should be incorporated into management strategies of restored wetlands. Close

• 87. [Article] Establishing the Inundation Distance and Overtopping Height of Paleotsunami from the Late-Holocene Geologic Record at Open-Coastal Wetland Sites, Central Cascadia Margin

  Mapping and stratigraphic investigations of back barrier, open-coastal plain sites have been used to establish minimum inundation distances and wave heights of tsunami produced by great subduction zone ...

  Citation × Citation Citation Abstract Copy Title: Establishing the Inundation Distance and Overtopping Height of Paleotsunami from the Late-Holocene Geologic Record at Open-Coastal Wetland Sites, Central Cascadia Margin Author: Schlichting, Robert B. Year: 2000 Mapping and stratigraphic investigations of back barrier, open-coastal plain sites have been used to establish minimum inundation distances and wave heights of tsunami produced by great subduction zone earthquakes in the central Cascadia margin. Cascadia tsunami deposits have been reported for many coseismic subsidence events in bay marsh settings where tidal-channel features focus tsunami energy. Variable magnitude (8.5±0.5 Mw), frequency (500±300 yr recurrence), and rupture geometry produce widely varying computer model outcomes for Casdcadia tsunami inundation. The results presented in this thesis provide specific quantitative data regarding tsunami inundation at the open coast. Anomalous sand sheets that have been characterized consist of well-sorted beach sand that fine up-section. The thickness of the deposits vary from 45 em to 0.2 em, and thin in the landward direction. Many of the sand layers include detrital caps. One to three detritus and mud lamina are intra-layered in the deposits. Marine diatoms and bromine, a marine tracer, increase in concentration at each of the sand layers. Title: Establishing the Inundation Distance and Overtopping Height of Paleotsunami from the Late-Holocene Geologic Record at Open-Coastal Wetland Sites, Central Cascadia Margin Author: Schlichting, Robert B. Year: 2000 Mapping and stratigraphic investigations of back barrier, open-coastal plain sites have been used to establish minimum inundation distances and wave heights of tsunami produced by great subduction zone earthquakes in the central Cascadia margin. Cascadia tsunami deposits have been reported for many coseismic subsidence events in bay marsh settings where tidal-channel features focus tsunami energy. Variable magnitude (8.5±0.5 Mw), frequency (500±300 yr recurrence), and rupture geometry produce widely varying computer model outcomes for Casdcadia tsunami inundation. The results presented in this thesis provide specific quantitative data regarding tsunami inundation at the open coast. Anomalous sand sheets that have been characterized consist of well-sorted beach sand that fine up-section. The thickness of the deposits vary from 45 em to 0.2 em, and thin in the landward direction. Many of the sand layers include detrital caps. One to three detritus and mud lamina are intra-layered in the deposits. Marine diatoms and bromine, a marine tracer, increase in concentration at each of the sand layers. Close

• 88. [Article] Black and Green: How Disinvestment, Displacement and Segregation Created the Conditions For Eco-Gentrification in Portland's Albina District, 1940-2015

  The historically African-American Albina District of Portland, Oregon holds a long track record of neighborhood neglect, devaluation and displacement of poor residents by private real estate companies ...

  Citation × Citation Citation Abstract Copy Title: Black and Green: How Disinvestment, Displacement and Segregation Created the Conditions For Eco-Gentrification in Portland's Albina District, 1940-2015 Author: Ause, Carter William Year: 2016 The historically African-American Albina District of Portland, Oregon holds a long track record of neighborhood neglect, devaluation and displacement of poor residents by private real estate companies and city government. Devaluation in the area was the direct result of discriminatory real estate policies and mid-20th Century urban renewal projects. Starting in the 1990s, the city passed revitalization measures to increase private investment in the neighborhood and few historians have tackled studies of recent sustainability-oriented gentrification resulting from revitalization. Though contemporary works in urban studies at Portland State University have looked at revitalization and subsequent ecological gentrification in the area, the subject of gentrification in Albina has not been adequately analyzed by historians. Ecological gentrification can be defined as an environmental planning agenda that leads to the displacement or exclusion of the most economically vulnerable human populations while espousing an environmental ethic. Using archival documents, public histories, social histories, newspaper articles, census data and works in urban studies, first this study analyzes residential segregation, displacement and disinvestment over a 50-year period (1940-1990). This 50-year period provides adequate context for examining sustainability-oriented real estate projects, rising rents, as well as changing racial and socioeconomic demographics over a 25-year period (1990-2015). Since the Vanport Flood in 1948, post-war urban renewal projects, segregationist redlining policies, faulty mortgage lenders and city-initiated revitalization efforts have formed the conditions for Albina’s recent wave of ecological gentrification. The issue here is not environmentalism itself, but rather the way in which environmentalism can be used to justify social and economic inequalities brought upon by new development. Title: Black and Green: How Disinvestment, Displacement and Segregation Created the Conditions For Eco-Gentrification in Portland's Albina District, 1940-2015 Author: Ause, Carter William Year: 2016 The historically African-American Albina District of Portland, Oregon holds a long track record of neighborhood neglect, devaluation and displacement of poor residents by private real estate companies and city government. Devaluation in the area was the direct result of discriminatory real estate policies and mid-20th Century urban renewal projects. Starting in the 1990s, the city passed revitalization measures to increase private investment in the neighborhood and few historians have tackled studies of recent sustainability-oriented gentrification resulting from revitalization. Though contemporary works in urban studies at Portland State University have looked at revitalization and subsequent ecological gentrification in the area, the subject of gentrification in Albina has not been adequately analyzed by historians. Ecological gentrification can be defined as an environmental planning agenda that leads to the displacement or exclusion of the most economically vulnerable human populations while espousing an environmental ethic. Using archival documents, public histories, social histories, newspaper articles, census data and works in urban studies, first this study analyzes residential segregation, displacement and disinvestment over a 50-year period (1940-1990). This 50-year period provides adequate context for examining sustainability-oriented real estate projects, rising rents, as well as changing racial and socioeconomic demographics over a 25-year period (1990-2015). Since the Vanport Flood in 1948, post-war urban renewal projects, segregationist redlining policies, faulty mortgage lenders and city-initiated revitalization efforts have formed the conditions for Albina’s recent wave of ecological gentrification. The issue here is not environmentalism itself, but rather the way in which environmentalism can be used to justify social and economic inequalities brought upon by new development. Close

• 89. [Article] Analyzing Dam Feasibility in the Willamette River Watershed

  This study conducts a dam-scale cost versus benefit analysis in order to explore the feasibility of each the 13 U.S. Army Corps of Engineers (USACE) commissioned dams in Oregon’s Willamette River network. ...

  Citation × Citation Citation Abstract Copy Title: Analyzing Dam Feasibility in the Willamette River Watershed Author: Nagel, Alexander Cameron Year: 2017 This study conducts a dam-scale cost versus benefit analysis in order to explore the feasibility of each the 13 U.S. Army Corps of Engineers (USACE) commissioned dams in Oregon’s Willamette River network. Constructed between 1941 and 1969, these structures function in collaboration to comprise the Willamette River Basin Reservoir System (WRBRS). The motivation for this project derives from a growing awareness of the biophysical impacts that dam structures can have on riparian habitats. This project compares each of the 13 dams being assessed, to prioritize their level of utility within the system. The study takes the metrics from the top three services (flood regulation, hydropower generation and recreation) and disservices (fish mortality, structural risk and water temperature hazards) and creates a rubric that scores the feasibility of each dam within the system. Within a range between 0 to 3 for three dam services and 0 to -4.5 for two disservices, the overall calculated score elucidates for each structure whether its contribution to the WRBRS is positive or negative. Further analysis searches for spatiotemporal trends such as anomalous tributaries or magnified structural risk for structures exceeding a certain age. GIS data from the National Inventory of Dams (NID), U.S. Geologic Survey (USGS) water measurements, raw data from USACE, and peer-reviewed studies comprise the statistics that generate results for this analysis. The computed scores for each dam yield an average overall score of -1.31, and nine of the 13 structures have negative results, indicating that the WRBRS faces challenges going forward. The study seeks to contribute to the increasingly relevant examination of dam networks at the watershed scale. Title: Analyzing Dam Feasibility in the Willamette River Watershed Author: Nagel, Alexander Cameron Year: 2017 This study conducts a dam-scale cost versus benefit analysis in order to explore the feasibility of each the 13 U.S. Army Corps of Engineers (USACE) commissioned dams in Oregon’s Willamette River network. Constructed between 1941 and 1969, these structures function in collaboration to comprise the Willamette River Basin Reservoir System (WRBRS). The motivation for this project derives from a growing awareness of the biophysical impacts that dam structures can have on riparian habitats. This project compares each of the 13 dams being assessed, to prioritize their level of utility within the system. The study takes the metrics from the top three services (flood regulation, hydropower generation and recreation) and disservices (fish mortality, structural risk and water temperature hazards) and creates a rubric that scores the feasibility of each dam within the system. Within a range between 0 to 3 for three dam services and 0 to -4.5 for two disservices, the overall calculated score elucidates for each structure whether its contribution to the WRBRS is positive or negative. Further analysis searches for spatiotemporal trends such as anomalous tributaries or magnified structural risk for structures exceeding a certain age. GIS data from the National Inventory of Dams (NID), U.S. Geologic Survey (USGS) water measurements, raw data from USACE, and peer-reviewed studies comprise the statistics that generate results for this analysis. The computed scores for each dam yield an average overall score of -1.31, and nine of the 13 structures have negative results, indicating that the WRBRS faces challenges going forward. The study seeks to contribute to the increasingly relevant examination of dam networks at the watershed scale. Close

• 90. [Article] Wet Meadow Plant Associations, Malheur National Wildlife Refuge, Harney County, Oregon

  In July 2012, we sampled 131 plots in wet meadow habitat at the southern end of the Malheur National Wildlife Refuge. Analysis of the data identified eleven different plant associations: Alopecurus pratensis, ...

  Citation × Citation Citation Abstract Copy Title: Wet Meadow Plant Associations, Malheur National Wildlife Refuge, Harney County, Oregon Author: Christy, John A. Year: 2013 In July 2012, we sampled 131 plots in wet meadow habitat at the southern end of the Malheur National Wildlife Refuge. Analysis of the data identified eleven different plant associations: Alopecurus pratensis, Carex aquatilis var. aquatilis, Carex nebrascensis, Carex pellita, Carex praegracilis, Carex sheldonii, Distichlis spicata, Juncus balticus, Leymus triticoides, Phalaris arundinacea, and Sparganium eurycarpum. Plant associations spanned a wetland gradient from seasonally moist to seasonally or perennially flooded, but surface water had left most stands at time of sampling. Mean Wetland Indicator Status scores help to place the plant associations within gradients in soil moisture and alkalinity. The Alopecurus pratensis and Phalaris arundinacea associations are dominated by exotic, invasive species and appear to be outcompeting native plant associations. Phases of the Carex praegracilis association appear to be replaced by the Alopecurus pratensis association, while the Carex pellita, Juncus balticus, and Leymus triticoides associations may be replaced by the Phalaris arundinacea association. The Carex aquatilis and Sparganium eurycarpum associations were undersampled and provide only an estimate of composition. Most associations are consistent with what has been included in the National Vegetation Classification. Title: Wet Meadow Plant Associations, Malheur National Wildlife Refuge, Harney County, Oregon Author: Christy, John A. Year: 2013 In July 2012, we sampled 131 plots in wet meadow habitat at the southern end of the Malheur National Wildlife Refuge. Analysis of the data identified eleven different plant associations: Alopecurus pratensis, Carex aquatilis var. aquatilis, Carex nebrascensis, Carex pellita, Carex praegracilis, Carex sheldonii, Distichlis spicata, Juncus balticus, Leymus triticoides, Phalaris arundinacea, and Sparganium eurycarpum. Plant associations spanned a wetland gradient from seasonally moist to seasonally or perennially flooded, but surface water had left most stands at time of sampling. Mean Wetland Indicator Status scores help to place the plant associations within gradients in soil moisture and alkalinity. The Alopecurus pratensis and Phalaris arundinacea associations are dominated by exotic, invasive species and appear to be outcompeting native plant associations. Phases of the Carex praegracilis association appear to be replaced by the Alopecurus pratensis association, while the Carex pellita, Juncus balticus, and Leymus triticoides associations may be replaced by the Phalaris arundinacea association. The Carex aquatilis and Sparganium eurycarpum associations were undersampled and provide only an estimate of composition. Most associations are consistent with what has been included in the National Vegetation Classification. Close

• 91. [Article] A Geospatial Tool for Wetland Prioritization at the Watershed Scale

  There is an increasing demand for assessing ecosystem functions for freshwater wetlands, especially when comparing or prioritizing among wetlands at the watershed scale. We estimated the relative potential ...

  Citation × Citation Citation Abstract Copy Title: A Geospatial Tool for Wetland Prioritization at the Watershed Scale Author: Blackmore, Debra Sue, Chang, Heejun Year: 2015 There is an increasing demand for assessing ecosystem functions for freshwater wetlands, especially when comparing or prioritizing among wetlands at the watershed scale. We estimated the relative potential of selected ecosystem functions for freshwater wetlands within a watershed using widely available geospatial data. We developed four functions to estimate 1) flood storage, 2) late season flow, 3) sediment retention and 4) temperature control in four pilot watersheds in Oregon (Tualatin, Coquille, Upper Grande Ronde and Sprague). These watersheds are geographically separated from each other representing diverse ecoregion environments. Spatial analysis and geographic information system (GIS) were designed for maximum re-use, based on publicly-available data, commonly-used software, semi-automated techniques and wetland characterizations that attempt to capture fundamental wetland processes. Our data sources include 30-meter digital elevation models, NRCS soil survey extracts, USGS National Land Cover Data, USGS HUC8 boundaries (polygons) and statewide wetland delineations (polygons) processed within ArcGIS 10.2 and Python 2.7.5 software. Model parameters were compiled using multiple proxy values for size, slope, aspect, proximity, flow path distance, hydrologic gradient, shade, and soil characteristics. WPT characterizations emphasize the multi-faceted value of freshwater wetlands, relating potential within a watershed as well as providing model-based characterizations between watersheds. Our wetland prioritization tool (WPT) provides useful information to estimate and compare the relative potential for selected wetland functions, thereby improving success in wetland conservation, restoration, and mitigation efforts. Title: A Geospatial Tool for Wetland Prioritization at the Watershed Scale Author: Blackmore, Debra Sue, Chang, Heejun Year: 2015 There is an increasing demand for assessing ecosystem functions for freshwater wetlands, especially when comparing or prioritizing among wetlands at the watershed scale. We estimated the relative potential of selected ecosystem functions for freshwater wetlands within a watershed using widely available geospatial data. We developed four functions to estimate 1) flood storage, 2) late season flow, 3) sediment retention and 4) temperature control in four pilot watersheds in Oregon (Tualatin, Coquille, Upper Grande Ronde and Sprague). These watersheds are geographically separated from each other representing diverse ecoregion environments. Spatial analysis and geographic information system (GIS) were designed for maximum re-use, based on publicly-available data, commonly-used software, semi-automated techniques and wetland characterizations that attempt to capture fundamental wetland processes. Our data sources include 30-meter digital elevation models, NRCS soil survey extracts, USGS National Land Cover Data, USGS HUC8 boundaries (polygons) and statewide wetland delineations (polygons) processed within ArcGIS 10.2 and Python 2.7.5 software. Model parameters were compiled using multiple proxy values for size, slope, aspect, proximity, flow path distance, hydrologic gradient, shade, and soil characteristics. WPT characterizations emphasize the multi-faceted value of freshwater wetlands, relating potential within a watershed as well as providing model-based characterizations between watersheds. Our wetland prioritization tool (WPT) provides useful information to estimate and compare the relative potential for selected wetland functions, thereby improving success in wetland conservation, restoration, and mitigation efforts. Close

• 92. [Article] History, Current Conditions, and Wetland Restoration at Killin Wetlands Natural Area, Washington County, Oregon

  In September 2014, the Metro Natural Area Program engaged The Wetland Conservancy to develop a scientific assessment of Metro’s 590-acre Killin Wetlands Natural Area. Metro acquired the lands comprising ...

  Citation × Citation Citation Abstract Copy Title: History, Current Conditions, and Wetland Restoration at Killin Wetlands Natural Area, Washington County, Oregon Author: Christy, John A. Year: 2015 In September 2014, the Metro Natural Area Program engaged The Wetland Conservancy to develop a scientific assessment of Metro’s 590-acre Killin Wetlands Natural Area. Metro acquired the lands comprising the KWNA between 2000 and 2012 with funds from two voterapproved open space bond measures. Since 2000, Metro has sought to advance natural area restoration at the site, focusing on the suppression of non-native pasture weeds and planting of native trees and shrubs in higher parts of the floodplain and its edges. Most uplands in Metro ownership have been maintained in agriculture through leased partnerships with local farmers. Metro and its partners have observed the effects of persistent flooding at the site, which began prior to Metro’s acquisition of the property. Most notable has been the decline of the once abundant Geyer willow stand, a prominent and valued feature of the site. In February 2014, Metro convened several key scientists familiar with the wetland, and its underlying Labish soil, to discuss what was known about the Killin Wetlands and possible next steps in advancing restoration there. That discussion focused on the subsidence of organic soils, caused by artificial drainage, and led to the recommendation that a review of regional peat soil wetlands would be an important step in developing an informed plan for preserving and restoring Killin Wetlands. This report presents that review. Title: History, Current Conditions, and Wetland Restoration at Killin Wetlands Natural Area, Washington County, Oregon Author: Christy, John A. Year: 2015 In September 2014, the Metro Natural Area Program engaged The Wetland Conservancy to develop a scientific assessment of Metro’s 590-acre Killin Wetlands Natural Area. Metro acquired the lands comprising the KWNA between 2000 and 2012 with funds from two voterapproved open space bond measures. Since 2000, Metro has sought to advance natural area restoration at the site, focusing on the suppression of non-native pasture weeds and planting of native trees and shrubs in higher parts of the floodplain and its edges. Most uplands in Metro ownership have been maintained in agriculture through leased partnerships with local farmers. Metro and its partners have observed the effects of persistent flooding at the site, which began prior to Metro’s acquisition of the property. Most notable has been the decline of the once abundant Geyer willow stand, a prominent and valued feature of the site. In February 2014, Metro convened several key scientists familiar with the wetland, and its underlying Labish soil, to discuss what was known about the Killin Wetlands and possible next steps in advancing restoration there. That discussion focused on the subsidence of organic soils, caused by artificial drainage, and led to the recommendation that a review of regional peat soil wetlands would be an important step in developing an informed plan for preserving and restoring Killin Wetlands. This report presents that review. Close

• 93. [Article] Decadal Ecosystem Response to an Anomalous Melt Season in a Polar Desert in Antarctica

  Amplified climate change in polar regions is significantly altering regional ecosystems, yet there are few long-term records documenting these responses. The McMurdo Dry Valleys (MDV) cold desert ecosystem ...

  Citation × Citation Citation Abstract Copy Title: Decadal Ecosystem Response to an Anomalous Melt Season in a Polar Desert in Antarctica Author: Gooseff, Michael N., Barrett, John E., Adams, Byron J., Doran, Peter T., Fountain, Andrew J., Lyons, W. Berry, McKnight, Diana M., Priscu, John C., Sokol, Eric R., Takacs-Vesbach, Cristina, Vandegehuchte, Martijn L., Virginia, Ross A., Wall, Diana H. Year: 2017 Amplified climate change in polar regions is significantly altering regional ecosystems, yet there are few long-term records documenting these responses. The McMurdo Dry Valleys (MDV) cold desert ecosystem is the largest ice-free area of Antarctica, comprising soils, glaciers, meltwater streams and permanently ice-covered lakes. Multi-decadal records indicate that the MDV exhibited a distinct ecosystem response to an uncharacteristic austral summer and ensuing climatic shift. A decadal summer cooling phase ended in 2002 with intense glacial melt (‘flood year’)—a step-change in water availability triggering distinct changes in the ecosystem. Before 2002, the ecosystem exhibited synchronous behaviour: declining stream flow, decreasing lake levels, thickening lake ice cover, decreasing primary production in lakes and streams, and diminishing soil secondary production. Since 2002, summer air temperatures and solar flux have been relatively consistent, leading to lake level rise, lake ice thinning and elevated stream flow. Biological responses varied; one stream cyanobacterial mat type immediately increased production, but another stream mat type, soil invertebrates and lake primary productivity responded asynchronously a few years after 2002. This ecosystem response to a climatic anomaly demonstrates differential biological community responses to substantial perturbations, and the mediation of biological responses to climate change by changes in physical ecosystem properties. Title: Decadal Ecosystem Response to an Anomalous Melt Season in a Polar Desert in Antarctica Author: Gooseff, Michael N., Barrett, John E., Adams, Byron J., Doran, Peter T., Fountain, Andrew J., Lyons, W. Berry, McKnight, Diana M., Priscu, John C., Sokol, Eric R., Takacs-Vesbach, Cristina, Vandegehuchte, Martijn L., Virginia, Ross A., Wall, Diana H. Year: 2017 Amplified climate change in polar regions is significantly altering regional ecosystems, yet there are few long-term records documenting these responses. The McMurdo Dry Valleys (MDV) cold desert ecosystem is the largest ice-free area of Antarctica, comprising soils, glaciers, meltwater streams and permanently ice-covered lakes. Multi-decadal records indicate that the MDV exhibited a distinct ecosystem response to an uncharacteristic austral summer and ensuing climatic shift. A decadal summer cooling phase ended in 2002 with intense glacial melt (‘flood year’)—a step-change in water availability triggering distinct changes in the ecosystem. Before 2002, the ecosystem exhibited synchronous behaviour: declining stream flow, decreasing lake levels, thickening lake ice cover, decreasing primary production in lakes and streams, and diminishing soil secondary production. Since 2002, summer air temperatures and solar flux have been relatively consistent, leading to lake level rise, lake ice thinning and elevated stream flow. Biological responses varied; one stream cyanobacterial mat type immediately increased production, but another stream mat type, soil invertebrates and lake primary productivity responded asynchronously a few years after 2002. This ecosystem response to a climatic anomaly demonstrates differential biological community responses to substantial perturbations, and the mediation of biological responses to climate change by changes in physical ecosystem properties. Close

• 94. [Article] Historical and Existing Vascular and Bryophyte Flora, Former Blue Heron Paper Mill, Willamette Falls, Oregon City, Oregon

  Willamette Falls has long been a focus of botanical interest, but industrial development at the site has limited public access for over a century. The closure of the Blue Heron paper mill on the south ...

  Citation × Citation Citation Abstract Copy Title: Historical and Existing Vascular and Bryophyte Flora, Former Blue Heron Paper Mill, Willamette Falls, Oregon City, Oregon Author: Christy, John A., Gaddis, Philip Year: 2015 Willamette Falls has long been a focus of botanical interest, but industrial development at the site has limited public access for over a century. The closure of the Blue Heron paper mill on the south bank of the river, and proposed redevelopment of the site, has given planners an opportunity to revisit this part of the falls and identify its current flora. As part of the preconstruction planning process for public access to the falls, Metro contracted John Christy to document the historical and existing vascular flora on the site, and Philip Gaddis joined us to document the bryophyte flora. For millennia, the falls has been a magnet for fishing, settlement, and more recent industrial development. Photographs by Carleton Watkins show that the south bank of the river at Willamette Falls had been modified for industrial uses as early as 1867. Infrastructure included dams and spillways to create a boat basin, and millraces to power a sawmill, gristmill, and woolen mill. Later, paper mills and electrical generating stations were built on both sides of the falls. These activities concentrated at the falls have impacted all native habitat except vertical cliff faces on basalt outcrops along the river. Significant portions of the shoreline at the Blue Heron site have been modified by fill. Remaining habitat in natural or semi-natural condition includes areas hydrated by tidal action of the Willamette River, areas of seasonal or perennial seepage below spillways and the old grinders, and basalt outcrops with varying exposures. The basalt outcrops are a relic of the Bretz or Missoula Floods (Allen et al. 1986), and exposures along this part of the Willamette River provide outlier habitat for both mesic and xeric species more common in the Columbia River Gorge (Detling 1958). Willamette Falls has a similar history to that of Niagara Falls in terms of industrial development, presence of a rock substrate supporting disjunct populations of rare plants, and botanical exploration that occurred primarily between 1885 and 1915 (Eckel 2013). Title: Historical and Existing Vascular and Bryophyte Flora, Former Blue Heron Paper Mill, Willamette Falls, Oregon City, Oregon Author: Christy, John A., Gaddis, Philip Year: 2015 Willamette Falls has long been a focus of botanical interest, but industrial development at the site has limited public access for over a century. The closure of the Blue Heron paper mill on the south bank of the river, and proposed redevelopment of the site, has given planners an opportunity to revisit this part of the falls and identify its current flora. As part of the preconstruction planning process for public access to the falls, Metro contracted John Christy to document the historical and existing vascular flora on the site, and Philip Gaddis joined us to document the bryophyte flora. For millennia, the falls has been a magnet for fishing, settlement, and more recent industrial development. Photographs by Carleton Watkins show that the south bank of the river at Willamette Falls had been modified for industrial uses as early as 1867. Infrastructure included dams and spillways to create a boat basin, and millraces to power a sawmill, gristmill, and woolen mill. Later, paper mills and electrical generating stations were built on both sides of the falls. These activities concentrated at the falls have impacted all native habitat except vertical cliff faces on basalt outcrops along the river. Significant portions of the shoreline at the Blue Heron site have been modified by fill. Remaining habitat in natural or semi-natural condition includes areas hydrated by tidal action of the Willamette River, areas of seasonal or perennial seepage below spillways and the old grinders, and basalt outcrops with varying exposures. The basalt outcrops are a relic of the Bretz or Missoula Floods (Allen et al. 1986), and exposures along this part of the Willamette River provide outlier habitat for both mesic and xeric species more common in the Columbia River Gorge (Detling 1958). Willamette Falls has a similar history to that of Niagara Falls in terms of industrial development, presence of a rock substrate supporting disjunct populations of rare plants, and botanical exploration that occurred primarily between 1885 and 1915 (Eckel 2013). Close

• 95. [Article] Wet Meadow Plant Associations, Double O Unit, Malheur National Wildlife Refuge, Harney County, Oregon

  This report summarizes vegetation data collected in July 2015 in wet meadow and marshy habitats on the Double O Unit of Malheur National Wildlife Refuge (MNWR). Because vegetation sampled at the Double ...

  Citation × Citation Citation Abstract Copy Title: Wet Meadow Plant Associations, Double O Unit, Malheur National Wildlife Refuge, Harney County, Oregon Author: Christy, John A. Year: 2016 This report summarizes vegetation data collected in July 2015 in wet meadow and marshy habitats on the Double O Unit of Malheur National Wildlife Refuge (MNWR). Because vegetation sampled at the Double O was wetter and more alkaline than wet meadows sampled at the south end of the refuge in 2012 and 2013 (Christy 2014), data from the Double O Unit were analyzed and summarized separately. A total of 83 plots were sampled in 2015, and analysis of the data identified 14 plant associations: Alopecurus aequalis - Juncus balticus, Alopecurus pratensis - Potentilla anserina, Carex praegracilis - Juncus balticus, Cicuta douglasii - Carex nebrascensis, Distichlis spicata - Amphiscirpus nevadensis, Distichlis spicata - Nitrophila occidentalis, Eleocharis palustris - Juncus balticus, Eleocharis rostellata, Juncus balticus - Glaux maritima, Hippuris vulgaris - Triglochin maritima, Leymus triticoides - Juncus balticus, Schoenoplectus americanus, Spartina gracilis, and Triglochin maritima. Plant associations spanned a wetland gradient from seasonally moist to seasonally or perennially flooded, but surface water had left most stands at time of sampling. Mean Wetland Indicator Status scores and species composition help to place the plant associations within gradients in soil moisture and alkalinity. Seven of the 14 plant associations are listed in the International Vegetation Classification, and the remaining types are provisional Title: Wet Meadow Plant Associations, Double O Unit, Malheur National Wildlife Refuge, Harney County, Oregon Author: Christy, John A. Year: 2016 This report summarizes vegetation data collected in July 2015 in wet meadow and marshy habitats on the Double O Unit of Malheur National Wildlife Refuge (MNWR). Because vegetation sampled at the Double O was wetter and more alkaline than wet meadows sampled at the south end of the refuge in 2012 and 2013 (Christy 2014), data from the Double O Unit were analyzed and summarized separately. A total of 83 plots were sampled in 2015, and analysis of the data identified 14 plant associations: Alopecurus aequalis - Juncus balticus, Alopecurus pratensis - Potentilla anserina, Carex praegracilis - Juncus balticus, Cicuta douglasii - Carex nebrascensis, Distichlis spicata - Amphiscirpus nevadensis, Distichlis spicata - Nitrophila occidentalis, Eleocharis palustris - Juncus balticus, Eleocharis rostellata, Juncus balticus - Glaux maritima, Hippuris vulgaris - Triglochin maritima, Leymus triticoides - Juncus balticus, Schoenoplectus americanus, Spartina gracilis, and Triglochin maritima. Plant associations spanned a wetland gradient from seasonally moist to seasonally or perennially flooded, but surface water had left most stands at time of sampling. Mean Wetland Indicator Status scores and species composition help to place the plant associations within gradients in soil moisture and alkalinity. Seven of the 14 plant associations are listed in the International Vegetation Classification, and the remaining types are provisional Close

• 96. [Article] Science and Practice of Integrated River Basin Management : Lessons from North and Central American UNESCO-HELP Basins

  The Hydrology for the Environment, Life and Policy (HELP) program, a cross-cutting component of the UNESCO International Hydrological Programme (IHP), has as its goal to facilitate dialogue among hydrologists, ...

  Citation × Citation Citation Abstract Copy Title: Science and Practice of Integrated River Basin Management : Lessons from North and Central American UNESCO-HELP Basins Author: Chang, Heejun, Browning-Aiken, Anne Year: 2010 The Hydrology for the Environment, Life and Policy (HELP) program, a cross-cutting component of the UNESCO International Hydrological Programme (IHP), has as its goal to facilitate dialogue among hydrologists, social and economic scientists, water resource managers, water lawyers, policy experts, and river basin stakeholder communities in setting a research agenda driven by local management and policy issues. HELP seeks to improve the benefits to society by applying the principals of integrated water-resources management to complex, interdisciplinary issues within catchments. This Monograph is the culmination of a workshop held in 2010 in which the managers from the six North American basins (San Pedro, Willamette, Upper Washita, Lake Champlain, Iowa-Cedar, Luquillo) and a Central American basin (Panama Canal), see Figure 1, met to exchange ideas and “lessons learned” in various applications of IWRM within the HELP philosophy. Three major themes were examined: 1. Climate change: Creating watershed resilience 2. Use of social learning in IWRM 3. Knowledge and information management for IWRM Each of these themes is explored in detail and enhanced with case studies of IWRM applications from the participating North and Central American HELP basins. Title: Science and Practice of Integrated River Basin Management : Lessons from North and Central American UNESCO-HELP Basins Author: Chang, Heejun, Browning-Aiken, Anne Year: 2010 The Hydrology for the Environment, Life and Policy (HELP) program, a cross-cutting component of the UNESCO International Hydrological Programme (IHP), has as its goal to facilitate dialogue among hydrologists, social and economic scientists, water resource managers, water lawyers, policy experts, and river basin stakeholder communities in setting a research agenda driven by local management and policy issues. HELP seeks to improve the benefits to society by applying the principals of integrated water-resources management to complex, interdisciplinary issues within catchments. This Monograph is the culmination of a workshop held in 2010 in which the managers from the six North American basins (San Pedro, Willamette, Upper Washita, Lake Champlain, Iowa-Cedar, Luquillo) and a Central American basin (Panama Canal), see Figure 1, met to exchange ideas and “lessons learned” in various applications of IWRM within the HELP philosophy. Three major themes were examined: 1. Climate change: Creating watershed resilience 2. Use of social learning in IWRM 3. Knowledge and information management for IWRM Each of these themes is explored in detail and enhanced with case studies of IWRM applications from the participating North and Central American HELP basins. Close

• 97. [Article] The Value of New Jersey's Ecosystem Services and Natural Capital

  This report summarizes the results of a two-year study of the economic value of New Jersey's natural capital. Natural capital consists of those components of the natural environment that provide a long-term ...

  Citation × Citation Citation Abstract Copy Title: The Value of New Jersey's Ecosystem Services and Natural Capital Author: Costanza, Robert, Wilson, Matthew A., Troy, Austin, Voinov, Alexey, Liu, Shang, D'Agostino, John Year: 2006 This report summarizes the results of a two-year study of the economic value of New Jersey's natural capital. Natural capital consists of those components of the natural environment that provide a long-term stream of benefits to individual people and to society as a whole; the value of natural capital is defined in this report as the present value of that benefit stream. Many of the benefits provided by natural capital come from ecological systems ('ecosystems'); an ecosystem is a dynamic complex of plant, animal, and microorganism communities and their nonliving environment, all interacting as a functional unit. The benefits provided by natural capital include both goods and services; goods come from both ecosystems (e.g., timber) and abiotic (non-living) sources (e.g., mineral deposits), while services are are mainly provided by ecosystems. Examples of ecosystem services ('ecoservices') include temporary storage of flood waters by wetlands, long-term storage of climate-altering greenhouse gases in forests, dilution and assimilation of wastes by rivers, and numerous others. All of these services provide economic value to human beings. The goods provided by New Jersey's natural capital are covered in a separate study; this report focuses on the services provided the state's ecosystems, covering twelve different types of ecosystem and twelve different ecoservices. For policy, planning, and regulatory decisions, it is important for New Jerseyans to know not only what ecosystem goods and services will be affected by public and private actions, but also what their economic value is relative to other marketed and non-marketed goods and services, such as those provided by physical capital (e.g., roads), human capital investment (e.g., education), etc. As a way of expressing these relative values or "trade-offs", this study estimated the dollar value of the ecoservices produced by New Jersey's ecosystems. In deriving these estimates, we used three different approaches: value transfer, hedonic analysis, and spatial modeling. Title: The Value of New Jersey's Ecosystem Services and Natural Capital Author: Costanza, Robert, Wilson, Matthew A., Troy, Austin, Voinov, Alexey, Liu, Shang, D'Agostino, John Year: 2006 This report summarizes the results of a two-year study of the economic value of New Jersey's natural capital. Natural capital consists of those components of the natural environment that provide a long-term stream of benefits to individual people and to society as a whole; the value of natural capital is defined in this report as the present value of that benefit stream. Many of the benefits provided by natural capital come from ecological systems ('ecosystems'); an ecosystem is a dynamic complex of plant, animal, and microorganism communities and their nonliving environment, all interacting as a functional unit. The benefits provided by natural capital include both goods and services; goods come from both ecosystems (e.g., timber) and abiotic (non-living) sources (e.g., mineral deposits), while services are are mainly provided by ecosystems. Examples of ecosystem services ('ecoservices') include temporary storage of flood waters by wetlands, long-term storage of climate-altering greenhouse gases in forests, dilution and assimilation of wastes by rivers, and numerous others. All of these services provide economic value to human beings. The goods provided by New Jersey's natural capital are covered in a separate study; this report focuses on the services provided the state's ecosystems, covering twelve different types of ecosystem and twelve different ecoservices. For policy, planning, and regulatory decisions, it is important for New Jerseyans to know not only what ecosystem goods and services will be affected by public and private actions, but also what their economic value is relative to other marketed and non-marketed goods and services, such as those provided by physical capital (e.g., roads), human capital investment (e.g., education), etc. As a way of expressing these relative values or "trade-offs", this study estimated the dollar value of the ecoservices produced by New Jersey's ecosystems. In deriving these estimates, we used three different approaches: value transfer, hedonic analysis, and spatial modeling. Close

• 98. [Article] Modeling Historic Columbia River Flood Impacts

  The Lower Columbia River Estuary (LCRE) has undergone extensive modifications since the 19th century. Construction of dams, installation of jetties and dikes, dredging of the navigation channel and filling ...

  Citation × Citation Citation Abstract Copy Title: Modeling Historic Columbia River Flood Impacts Author: Helaire, Lumas, Mahedy, Andrew, Talke, Stefan A., Jay, David A Year: 2014 The Lower Columbia River Estuary (LCRE) has undergone extensive modifications since the 19th century. Construction of dams, installation of jetties and dikes, dredging of the navigation channel and filling in of tidal wetlands have all contributed significantly to alterations in tidal dynamics and the flow regime, with consequences for habitat inundation and salinity intrusion. In this talk we discuss the development and implementation of a 19th century flow model for the LCRE, using a digital elevation model based on historic bathymetry. The model has been calibrated with recently rediscovered and digitized tide data from the 19th century. In this research project we look at several river flow scenarios. We are interested in the interaction between river flow and ocean tides, how it has changed in the LCRE since the 19th century and how it affects the river physics. With the model, we focus on the following questions: How has the spatial structure of salinity changed since the 1890's? Has the salinity intrusion length increased or decreased? Is there a change in residual salinity in some of the bays in the estuary? How have changes to the bathymetric structure of the river affected salinity intrusion? For the same flow river flow, how have wetland inundation patterns changed? How have changes to the tidal prism ascertained from a temporal analysis of tidal records, affected the amount of land inundated in a tidal cycle and how long that land remains inundated? Initial results suggest that salinity intrusion patterns have shifted and that wetland inundation patterns have been impacted by the up to 10% increase in the estuary tidal range since the late 19th century. Title: Modeling Historic Columbia River Flood Impacts Author: Helaire, Lumas, Mahedy, Andrew, Talke, Stefan A., Jay, David A Year: 2014 The Lower Columbia River Estuary (LCRE) has undergone extensive modifications since the 19th century. Construction of dams, installation of jetties and dikes, dredging of the navigation channel and filling in of tidal wetlands have all contributed significantly to alterations in tidal dynamics and the flow regime, with consequences for habitat inundation and salinity intrusion. In this talk we discuss the development and implementation of a 19th century flow model for the LCRE, using a digital elevation model based on historic bathymetry. The model has been calibrated with recently rediscovered and digitized tide data from the 19th century. In this research project we look at several river flow scenarios. We are interested in the interaction between river flow and ocean tides, how it has changed in the LCRE since the 19th century and how it affects the river physics. With the model, we focus on the following questions: How has the spatial structure of salinity changed since the 1890's? Has the salinity intrusion length increased or decreased? Is there a change in residual salinity in some of the bays in the estuary? How have changes to the bathymetric structure of the river affected salinity intrusion? For the same flow river flow, how have wetland inundation patterns changed? How have changes to the tidal prism ascertained from a temporal analysis of tidal records, affected the amount of land inundated in a tidal cycle and how long that land remains inundated? Initial results suggest that salinity intrusion patterns have shifted and that wetland inundation patterns have been impacted by the up to 10% increase in the estuary tidal range since the late 19th century. Close

• 99. [Article] Winds of Change? Exploring Climate Change-Driven Migration and Related Impacts in the Pacific Northwest

  Climate change is expected to have significant impacts on the Pacific Northwest’s communities, economy, and natural systems. These impacts – which include reductions in summer water supply, the potential ...

  Citation × Citation Citation Abstract Copy Title: Winds of Change? Exploring Climate Change-Driven Migration and Related Impacts in the Pacific Northwest Author: Binder, Lara Whitely, Jurjevich, Jason R. Year: 2016 Climate change is expected to have significant impacts on the Pacific Northwest’s communities, economy, and natural systems. These impacts – which include reductions in summer water supply, the potential for more winter flooding and forest fires, threats to public health, and damage to coastal infrastructure due to sea level rise – will require changes in how communities evaluate, manage, and mitigate environmental risks. Despite these challenges, some have suggested that the region may be relatively well off compared to other areas of the U.S. and the world. This has led to growing speculation by the media, bloggers, and the public that “global warming could unleash a deluge of newcomers” (or “climate refugees”) to the Pacific Northwest in coming years.2The question is also gaining the attention of public sector professionals in the region. Planners and managers who engage in long-term planning for transportation, public health, utilities, and other public services want to understand whether population forecasts—an important analytical tool guiding many areas of regional planning—should reflect the possible impacts of climate change on migration flows, and if so, how? The connection between climate change and migration is the subject of a complex and emerging body of social science research. To help stimulate and inform research, and to provide guidance to decision makers on this issue, researchers at Portland State University and the University of Washington Climate Impacts Group convened experts in climate science, population dynamics, and public sector management to begin addressing the following central question: Do we need to be planning for more growth in Washington and Oregon because of climate change, and if so, what would a systematic framework for developing and updating migration scenarios for use in regional and state population growth and planning forecasts look like? The symposium—the first of its kind in the region and possibly the first of its kind in the United States—was held on June 24, 2016 at Portland State University. Title: Winds of Change? Exploring Climate Change-Driven Migration and Related Impacts in the Pacific Northwest Author: Binder, Lara Whitely, Jurjevich, Jason R. Year: 2016 Climate change is expected to have significant impacts on the Pacific Northwest’s communities, economy, and natural systems. These impacts – which include reductions in summer water supply, the potential for more winter flooding and forest fires, threats to public health, and damage to coastal infrastructure due to sea level rise – will require changes in how communities evaluate, manage, and mitigate environmental risks. Despite these challenges, some have suggested that the region may be relatively well off compared to other areas of the U.S. and the world. This has led to growing speculation by the media, bloggers, and the public that “global warming could unleash a deluge of newcomers” (or “climate refugees”) to the Pacific Northwest in coming years.2The question is also gaining the attention of public sector professionals in the region. Planners and managers who engage in long-term planning for transportation, public health, utilities, and other public services want to understand whether population forecasts—an important analytical tool guiding many areas of regional planning—should reflect the possible impacts of climate change on migration flows, and if so, how? The connection between climate change and migration is the subject of a complex and emerging body of social science research. To help stimulate and inform research, and to provide guidance to decision makers on this issue, researchers at Portland State University and the University of Washington Climate Impacts Group convened experts in climate science, population dynamics, and public sector management to begin addressing the following central question: Do we need to be planning for more growth in Washington and Oregon because of climate change, and if so, what would a systematic framework for developing and updating migration scenarios for use in regional and state population growth and planning forecasts look like? The symposium—the first of its kind in the region and possibly the first of its kind in the United States—was held on June 24, 2016 at Portland State University. Close

• 100. [Article] A Tectonic Study of a Part of the Northern Eagle Cap Wilderness Area, Northeastern Oregon

  Upper Triassic metavolcanic and metasedimentary strata in the study area are intruded by the Hurricane Divide and Craig Mountain Plutons of the Late Jurassic-Cretaceous Wallowa Batholith. The Clover Creek ...

  Citation × Citation Citation Abstract Copy Title: A Tectonic Study of a Part of the Northern Eagle Cap Wilderness Area, Northeastern Oregon Author: Neal, Kenneth Gordon Year: 1973 Upper Triassic metavolcanic and metasedimentary strata in the study area are intruded by the Hurricane Divide and Craig Mountain Plutons of the Late Jurassic-Cretaceous Wallowa Batholith. The Clover Creek Greenstone is overlain by the Martin Bridge Limestone, which is in tum overlain by the Hurwal Argillite; although the sequence is in normal stratigraphic order, contacts are generally tectonic. Concurrent with Early-Middle Jurassic regional deformation, during intermediate to mafic dikes, emplacement of the plutons of the Wallowa Batholith began. The plutons intruded vertically through the greenstone and limestone and then horizontally above the greenstone. This resulted in intense penetrative plastic deformation particularly of the Martin Bridge Limestone. Emplacement of the Hurricane Divide Pluton followed a northeast axis, and resulted in isoclinal folding and the formation of northerly trending synformal anticlines in the Martin Bridge atop a zone of uncoupling between the plastic limestone and the more rigid underlying Clover Creek metavolcanic basement. Subsequent final emplacement of the Craig Mountain Pluton caused cross folding of these anticlinal structures. Granitic plutonism was followed by regional uplift with associated faulting and erosion. Miocene Columbia River Basalt flood lavas were injected along many of the more northerly trending of these faults. This magmatism was concurrent with or followed by block uplift on the order of 1800 m of the Wallowa Mountains along the Wallowa Fault. Title: A Tectonic Study of a Part of the Northern Eagle Cap Wilderness Area, Northeastern Oregon Author: Neal, Kenneth Gordon Year: 1973 Upper Triassic metavolcanic and metasedimentary strata in the study area are intruded by the Hurricane Divide and Craig Mountain Plutons of the Late Jurassic-Cretaceous Wallowa Batholith. The Clover Creek Greenstone is overlain by the Martin Bridge Limestone, which is in tum overlain by the Hurwal Argillite; although the sequence is in normal stratigraphic order, contacts are generally tectonic. Concurrent with Early-Middle Jurassic regional deformation, during intermediate to mafic dikes, emplacement of the plutons of the Wallowa Batholith began. The plutons intruded vertically through the greenstone and limestone and then horizontally above the greenstone. This resulted in intense penetrative plastic deformation particularly of the Martin Bridge Limestone. Emplacement of the Hurricane Divide Pluton followed a northeast axis, and resulted in isoclinal folding and the formation of northerly trending synformal anticlines in the Martin Bridge atop a zone of uncoupling between the plastic limestone and the more rigid underlying Clover Creek metavolcanic basement. Subsequent final emplacement of the Craig Mountain Pluton caused cross folding of these anticlinal structures. Granitic plutonism was followed by regional uplift with associated faulting and erosion. Miocene Columbia River Basalt flood lavas were injected along many of the more northerly trending of these faults. This magmatism was concurrent with or followed by block uplift on the order of 1800 m of the Wallowa Mountains along the Wallowa Fault. Close