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• 1. [Article] The Influence of Recurrent Modes of Climate Variability on the Occurrence of Winter and Summer Extreme Temperatures over North America

  The influence of the Pacific–North American (PNA) pattern, the northern annular mode (NAM), and the El Ni~no–Southern Oscillation (ENSO) on extreme temperature days and months over North America is examined. ...

  Citation × Citation Citation Abstract Copy Title: The Influence of Recurrent Modes of Climate Variability on the Occurrence of Winter and Summer Extreme Temperatures over North America Author: Loikith, Paul C., Broccoli, Anthony J. Year: 2014 The influence of the Pacific–North American (PNA) pattern, the northern annular mode (NAM), and the El Ni~no–Southern Oscillation (ENSO) on extreme temperature days and months over North America is examined. Associations between extreme temperature days and months are strongest with the PNA and NAM andweaker for ENSO. In general, the associationwith extremes tends to be stronger onmonthly than daily time scales and for winter as compared to summer. Extreme temperatures are associated with the PNAandNAMin the vicinity of the centers of action of these circulation patterns; however, many extremes also occur on days when the amplitude and polarity of these patterns do not favor their occurrence. In winter, synoptic-scale, transient weather disturbances are important drivers of extreme temperature days; however, many of these smaller-scale events are concurrent with amplified PNA or NAMpatterns. Associations are weaker in summer when other physicalmechanisms affecting the surface energy balance, such as anomalous soilmoisture content, also influence the occurrence of extreme temperatures. Title: The Influence of Recurrent Modes of Climate Variability on the Occurrence of Winter and Summer Extreme Temperatures over North America Author: Loikith, Paul C., Broccoli, Anthony J. Year: 2014 The influence of the Pacific–North American (PNA) pattern, the northern annular mode (NAM), and the El Ni~no–Southern Oscillation (ENSO) on extreme temperature days and months over North America is examined. Associations between extreme temperature days and months are strongest with the PNA and NAM andweaker for ENSO. In general, the associationwith extremes tends to be stronger onmonthly than daily time scales and for winter as compared to summer. Extreme temperatures are associated with the PNAandNAMin the vicinity of the centers of action of these circulation patterns; however, many extremes also occur on days when the amplitude and polarity of these patterns do not favor their occurrence. In winter, synoptic-scale, transient weather disturbances are important drivers of extreme temperature days; however, many of these smaller-scale events are concurrent with amplified PNA or NAMpatterns. Associations are weaker in summer when other physicalmechanisms affecting the surface energy balance, such as anomalous soilmoisture content, also influence the occurrence of extreme temperatures. Close

• 2. [Article] Surface Temperature Probability Distributions in the NARCCAP Hindcast Experiment: Evaluation Methodology, Metrics, and Results

  Methodology is developed and applied to evaluate the characteristics of daily surface temperature distributions in a six-member regional climate model (RCM) hindcast experiment conducted as part of the ...

  Citation × Citation Citation Abstract Copy Title: Surface Temperature Probability Distributions in the NARCCAP Hindcast Experiment: Evaluation Methodology, Metrics, and Results Author: Loikith, Paul C., Waliser, Duane E., Lee, Huikyo, Kim, Jinwon, Neelin, J. David, Lintner, Benjamin R., McGinnis, Seth, Mattmann, Chris A., Mears, Linda O. Year: 2015 Methodology is developed and applied to evaluate the characteristics of daily surface temperature distributions in a six-member regional climate model (RCM) hindcast experiment conducted as part of the North American Regional Climate Change Assessment Program (NARCCAP). A surface temperature dataset combining gridded station observations and reanalysis is employed as the primary reference. Temperature biases are documented across the distribution, focusing on the median and tails. Temperature variance is generally higher in the RCMs than reference, while skewness is reasonably simulated in winter over the entire domain and over the western United States and Canada in summer. Substantial differences in skewness exist over the southern and eastern portions of the domain in summer. Four examples with observed long-tailed probability distribution functions (PDFs) are selected for model comparison. Long cold tails in the winter are simulated with high fidelity for Seattle, Washington, and Chicago, Illinois. In summer, theRCMs are unable to capture the distribution width and long warm tails for the coastal location of Los Angeles, California, while long cold tails are poorly realized for Houston, Texas. The evaluation results are repeated using two additional reanalysis products adjusted by station observations and two standard reanalysis products to assess the impact of observational uncertainty. Results are robust when compared with those obtained using the adjusted reanalysis products as reference, while larger uncertainties are introduced when standard reanalysis is employed as reference. Model biases identified in this work will allow for further investigation into associated mechanisms and implications for future simulations of temperature extremes. Title: Surface Temperature Probability Distributions in the NARCCAP Hindcast Experiment: Evaluation Methodology, Metrics, and Results Author: Loikith, Paul C., Waliser, Duane E., Lee, Huikyo, Kim, Jinwon, Neelin, J. David, Lintner, Benjamin R., McGinnis, Seth, Mattmann, Chris A., Mears, Linda O. Year: 2015 Methodology is developed and applied to evaluate the characteristics of daily surface temperature distributions in a six-member regional climate model (RCM) hindcast experiment conducted as part of the North American Regional Climate Change Assessment Program (NARCCAP). A surface temperature dataset combining gridded station observations and reanalysis is employed as the primary reference. Temperature biases are documented across the distribution, focusing on the median and tails. Temperature variance is generally higher in the RCMs than reference, while skewness is reasonably simulated in winter over the entire domain and over the western United States and Canada in summer. Substantial differences in skewness exist over the southern and eastern portions of the domain in summer. Four examples with observed long-tailed probability distribution functions (PDFs) are selected for model comparison. Long cold tails in the winter are simulated with high fidelity for Seattle, Washington, and Chicago, Illinois. In summer, theRCMs are unable to capture the distribution width and long warm tails for the coastal location of Los Angeles, California, while long cold tails are poorly realized for Houston, Texas. The evaluation results are repeated using two additional reanalysis products adjusted by station observations and two standard reanalysis products to assess the impact of observational uncertainty. Results are robust when compared with those obtained using the adjusted reanalysis products as reference, while larger uncertainties are introduced when standard reanalysis is employed as reference. Model biases identified in this work will allow for further investigation into associated mechanisms and implications for future simulations of temperature extremes. Close

• 3. [Article] Evaluation of Large‑Scale Meteorological Patterns Associated with Temperature Extremes in the NARCCAP Regional Climate Model Simulations

  Large-scale meteorological patterns (LSMPs) associated with temperature extremes are evaluated in a suite of regional climate model (RCM) simulations contributing to the North American Regional Climate ...

  Citation × Citation Citation Abstract Copy Title: Evaluation of Large‑Scale Meteorological Patterns Associated with Temperature Extremes in the NARCCAP Regional Climate Model Simulations Author: Loikith, Paul C., Waliser, Duane E., Lee, Huikyo, Neelin, J. David, Lintner, Benjamin, McGinnis, Seth, Mears, Linda, Kim, Jinwon Year: 2015 Large-scale meteorological patterns (LSMPs) associated with temperature extremes are evaluated in a suite of regional climate model (RCM) simulations contributing to the North American Regional Climate Change Assessment Program. LSMPs are characterized through composites of surface air temperature, sea level pressure, and 500 hPa geopotential height anomalies concurrent with extreme temperature days. Six of the seventeen RCM simulations are driven by boundary conditions from reanalysis while the other eleven are driven by one of four global climate models (GCMs). Four illustrative case studies are analyzed in detail. Model fidelity in LSMP spatial representation is high for cold winter extremes near Chicago. Winter warm extremes are captured by most RCMs in northern California, with some notable exceptions. Model fidelity is lower for cool summer days near Houston and extreme summer heat events in the Ohio Valley. Physical interpretation of these patterns and identification of wellsimulated cases, such as for Chicago, boosts confidence in the ability of these models to simulate days in the tails of the temperature distribution. Results appear consistent with the expectation that the ability of an RCM to reproduce a realistically shaped frequency distribution for temperature, especially at the tails, is related to its fidelity in simulating LMSPs. Each ensemble member is ranked for its ability to reproduce LSMPs associated with observed warm and cold extremes, identifying systematically high performing RCMs and the GCMs that provide superior boundary forcing. The methodology developed here provides a framework for identifying regions where further process-based evaluation would improve the understanding of simulation error and help guide future model improvement and downscaling efforts. Title: Evaluation of Large‑Scale Meteorological Patterns Associated with Temperature Extremes in the NARCCAP Regional Climate Model Simulations Author: Loikith, Paul C., Waliser, Duane E., Lee, Huikyo, Neelin, J. David, Lintner, Benjamin, McGinnis, Seth, Mears, Linda, Kim, Jinwon Year: 2015 Large-scale meteorological patterns (LSMPs) associated with temperature extremes are evaluated in a suite of regional climate model (RCM) simulations contributing to the North American Regional Climate Change Assessment Program. LSMPs are characterized through composites of surface air temperature, sea level pressure, and 500 hPa geopotential height anomalies concurrent with extreme temperature days. Six of the seventeen RCM simulations are driven by boundary conditions from reanalysis while the other eleven are driven by one of four global climate models (GCMs). Four illustrative case studies are analyzed in detail. Model fidelity in LSMP spatial representation is high for cold winter extremes near Chicago. Winter warm extremes are captured by most RCMs in northern California, with some notable exceptions. Model fidelity is lower for cool summer days near Houston and extreme summer heat events in the Ohio Valley. Physical interpretation of these patterns and identification of wellsimulated cases, such as for Chicago, boosts confidence in the ability of these models to simulate days in the tails of the temperature distribution. Results appear consistent with the expectation that the ability of an RCM to reproduce a realistically shaped frequency distribution for temperature, especially at the tails, is related to its fidelity in simulating LMSPs. Each ensemble member is ranked for its ability to reproduce LSMPs associated with observed warm and cold extremes, identifying systematically high performing RCMs and the GCMs that provide superior boundary forcing. The methodology developed here provides a framework for identifying regions where further process-based evaluation would improve the understanding of simulation error and help guide future model improvement and downscaling efforts. Close

• 4. [Article] Comparison between Observed and Model-Simulated Atmospheric CirculationPatterns Associated with Extreme Temperature Days over North AmericaUsing CMIP5 Historical Simulations

  Circulation patterns associated with extreme temperature days over North America, as simulated by a suite of climate models, are compared with those obtained from observations. The authors analyze 17 coupled ...

  Citation × Citation Citation Abstract Copy Title: Comparison between Observed and Model-Simulated Atmospheric CirculationPatterns Associated with Extreme Temperature Days over North AmericaUsing CMIP5 Historical Simulations Author: Loikith, Paul C., Broccoli, Anthony J. Year: 2015 Circulation patterns associated with extreme temperature days over North America, as simulated by a suite of climate models, are compared with those obtained from observations. The authors analyze 17 coupled atmosphere–ocean general circulation models contributing to the fifth phase of the Coupled Model Intercomparison Project. Circulation patterns are defined as composites of anomalies in sea level pressure and 500-hPa geopotential height concurrent with days in the tails of temperature distribution. Several metrics used to systematically describe circulation patterns associated with extreme temperature days are applied to both the observed and model-simulated data. Additionally, self-organizing maps are employed as a means of comparing observed and model-simulated circulation patterns across the North American domain. In general, the multimodel ensemble resembles the observed patterns well, especially in areas removed from complex geographic features (e.g., mountains and coastlines). Individual model results vary; however, the majority of models capture the major features observed. The multimodel ensemble captures several key features, including regional variations in the strength and orientation of atmospheric circulation patterns associated with extreme temperatures, both near the surface and aloft, as well as variations with latitude and season. The results from this work suggest that these models can be used to comprehensively examine the role that changes in atmospheric circulation will play in projected changes in temperature extremes because of future anthropogenic climate warming. Title: Comparison between Observed and Model-Simulated Atmospheric CirculationPatterns Associated with Extreme Temperature Days over North AmericaUsing CMIP5 Historical Simulations Author: Loikith, Paul C., Broccoli, Anthony J. Year: 2015 Circulation patterns associated with extreme temperature days over North America, as simulated by a suite of climate models, are compared with those obtained from observations. The authors analyze 17 coupled atmosphere–ocean general circulation models contributing to the fifth phase of the Coupled Model Intercomparison Project. Circulation patterns are defined as composites of anomalies in sea level pressure and 500-hPa geopotential height concurrent with days in the tails of temperature distribution. Several metrics used to systematically describe circulation patterns associated with extreme temperature days are applied to both the observed and model-simulated data. Additionally, self-organizing maps are employed as a means of comparing observed and model-simulated circulation patterns across the North American domain. In general, the multimodel ensemble resembles the observed patterns well, especially in areas removed from complex geographic features (e.g., mountains and coastlines). Individual model results vary; however, the majority of models capture the major features observed. The multimodel ensemble captures several key features, including regional variations in the strength and orientation of atmospheric circulation patterns associated with extreme temperatures, both near the surface and aloft, as well as variations with latitude and season. The results from this work suggest that these models can be used to comprehensively examine the role that changes in atmospheric circulation will play in projected changes in temperature extremes because of future anthropogenic climate warming. Close

• 5. [Article] Utilizing Humidity and Temperature Data to Advance Monitoring and Prediction of Meteorological Drought

  The fraction of land area over the Continental United States experiencing extreme hot and dry conditions has been increasing over the past several decades, consistent with expectation from anthropogenic ...

  Citation × Citation Citation Abstract Copy Title: Utilizing Humidity and Temperature Data to Advance Monitoring and Prediction of Meteorological Drought Author: Behrangi, Ali, Loikith, Paul C., Fetzer, Eric J., Nguyen, Hai M., Granger, Stephanie L. Year: 2015 The fraction of land area over the Continental United States experiencing extreme hot and dry conditions has been increasing over the past several decades, consistent with expectation from anthropogenic climate change. A clear concurrent change in precipitation, however, has not been confirmed. Vapor pressure deficit (VPD), combining temperature and humidity, is utilized here as an indicator of the background atmospheric conditions associated with meteorological drought. Furthermore, atmospheric conditions associated with warm season drought events are assessed by partitioning associated VPD anomalies into the temperature and humidity components. This approach suggests that the concurrence of anomalously high temperature and low humidity was an important driver of the rapid development and evolution of the exceptionally severe 2011 Texas and the 2012 Great Plains droughts. By classification of a decade of extreme drought events and tracking them back in time, it was found that near surface atmospheric temperature and humidity add essential information to the commonly used precipitation-based drought indicators and can advance efforts to determine the timing of drought onset and its severity. Title: Utilizing Humidity and Temperature Data to Advance Monitoring and Prediction of Meteorological Drought Author: Behrangi, Ali, Loikith, Paul C., Fetzer, Eric J., Nguyen, Hai M., Granger, Stephanie L. Year: 2015 The fraction of land area over the Continental United States experiencing extreme hot and dry conditions has been increasing over the past several decades, consistent with expectation from anthropogenic climate change. A clear concurrent change in precipitation, however, has not been confirmed. Vapor pressure deficit (VPD), combining temperature and humidity, is utilized here as an indicator of the background atmospheric conditions associated with meteorological drought. Furthermore, atmospheric conditions associated with warm season drought events are assessed by partitioning associated VPD anomalies into the temperature and humidity components. This approach suggests that the concurrence of anomalously high temperature and low humidity was an important driver of the rapid development and evolution of the exceptionally severe 2011 Texas and the 2012 Great Plains droughts. By classification of a decade of extreme drought events and tracking them back in time, it was found that near surface atmospheric temperature and humidity add essential information to the commonly used precipitation-based drought indicators and can advance efforts to determine the timing of drought onset and its severity. Close

• 6. [Article] Oregon Lake Watch, 2015 Annual Report

  The Oregon Lake Watch (OLW) volunteer monitoring program completed its third year of operation during 2015 with a focus on early detection of aquatic invasive species (AIS) and water quality status and ...

  Citation × Citation Citation Abstract Copy Title: Oregon Lake Watch, 2015 Annual Report Author: Cimino, Samuel, Miller, Rich, Strecker, Angela L. Year: 2015 The Oregon Lake Watch (OLW) volunteer monitoring program completed its third year of operation during 2015 with a focus on early detection of aquatic invasive species (AIS) and water quality status and trend assessments for the better management of Oregon’s lakes and reservoirs. AIS surveys emphasized the detection of Watch List aquatic plant and species that can have a negative impacts on the beneficial uses of our waterbodies. Water transparency and temperature measurements were used to track the condition of volunteers' lakes. Thirty-one Oregon lakes have been surveyed during the OLW’s three years, 16 of which were surveyed during 2015. Seven lakes have been surveyed all three years and seven more have been surveyed two of the three years. Four Watch List plant and one animal species were found during 2015. Eurasian watermilfoil (Myriophyllum spicatum) was found in three lakes, Brazilian elodea (Egeria densa) and curly leaf pondweed (Potamogeton crispus) were each found in two lakes, and yellow flag iris (Iris pseudacorus) was found in one lake. Asian clams (Corbicula fluminea) were found in one lake. A diverse array of native plants were found along with native signal crayfish (Pacifasticus leniusculus). Water quality ranged from eutrophic to oligotrophic conditions based on water transparency and water temperatures ranged as high as 28°C (82°F). More years of data collection are necessary to track water quality trends. Title: Oregon Lake Watch, 2015 Annual Report Author: Cimino, Samuel, Miller, Rich, Strecker, Angela L. Year: 2015 The Oregon Lake Watch (OLW) volunteer monitoring program completed its third year of operation during 2015 with a focus on early detection of aquatic invasive species (AIS) and water quality status and trend assessments for the better management of Oregon’s lakes and reservoirs. AIS surveys emphasized the detection of Watch List aquatic plant and species that can have a negative impacts on the beneficial uses of our waterbodies. Water transparency and temperature measurements were used to track the condition of volunteers' lakes. Thirty-one Oregon lakes have been surveyed during the OLW’s three years, 16 of which were surveyed during 2015. Seven lakes have been surveyed all three years and seven more have been surveyed two of the three years. Four Watch List plant and one animal species were found during 2015. Eurasian watermilfoil (Myriophyllum spicatum) was found in three lakes, Brazilian elodea (Egeria densa) and curly leaf pondweed (Potamogeton crispus) were each found in two lakes, and yellow flag iris (Iris pseudacorus) was found in one lake. Asian clams (Corbicula fluminea) were found in one lake. A diverse array of native plants were found along with native signal crayfish (Pacifasticus leniusculus). Water quality ranged from eutrophic to oligotrophic conditions based on water transparency and water temperatures ranged as high as 28°C (82°F). More years of data collection are necessary to track water quality trends. Close

• 7. [Article] Distributed Modeling of Ablation (1996–2011) and Climate Sensitivity on the Glaciers of Taylor Valley, Antarctica

  The McMurdo Dry Valleys of Antarctica host the coldest and driest ecosystem on Earth, which is acutely sensitive to the availability of water coming from glacial runoff. We modeled the spatial variability ...

  Citation × Citation Citation Abstract Copy Title: Distributed Modeling of Ablation (1996–2011) and Climate Sensitivity on the Glaciers of Taylor Valley, Antarctica Author: Hoffman, Matthew J., Fountain, Andrew G., Liston, Glen E. Year: 2016 The McMurdo Dry Valleys of Antarctica host the coldest and driest ecosystem on Earth, which is acutely sensitive to the availability of water coming from glacial runoff. We modeled the spatial variability in ablation and assessed climate sensitivity of the glacier ablation zones using 16 years of meteorological and surface mass-balance observations collected in Taylor Valley. Sublimation was the primary form of mass loss over much of the ablation zones, except for near the termini where melt, primarily below the surface, dominated. Microclimates in ~10 m scale topographic basins generated melt rates up to ten times higher than over smooth glacier surfaces. In contrast, the vertical terminal cliffs on the glaciers can have higher or lower melt rates than the horizontal surfaces due to differences in incoming solar radiation. The model systematically underpredicted ablation for the final 5 years studied, possibly due to an increase of windblown sediment. Surface mass-balance sensitivity to temperature was ~−0.02 m w.e. K−1, which is among the smallest magnitudes observed globally. We also identified a high sensitivity to ice albedo, with a decrease of 0.02 having similar effects as a 1 K increase in temperature, and a complex sensitivity to wind speed. Title: Distributed Modeling of Ablation (1996–2011) and Climate Sensitivity on the Glaciers of Taylor Valley, Antarctica Author: Hoffman, Matthew J., Fountain, Andrew G., Liston, Glen E. Year: 2016 The McMurdo Dry Valleys of Antarctica host the coldest and driest ecosystem on Earth, which is acutely sensitive to the availability of water coming from glacial runoff. We modeled the spatial variability in ablation and assessed climate sensitivity of the glacier ablation zones using 16 years of meteorological and surface mass-balance observations collected in Taylor Valley. Sublimation was the primary form of mass loss over much of the ablation zones, except for near the termini where melt, primarily below the surface, dominated. Microclimates in ~10 m scale topographic basins generated melt rates up to ten times higher than over smooth glacier surfaces. In contrast, the vertical terminal cliffs on the glaciers can have higher or lower melt rates than the horizontal surfaces due to differences in incoming solar radiation. The model systematically underpredicted ablation for the final 5 years studied, possibly due to an increase of windblown sediment. Surface mass-balance sensitivity to temperature was ~−0.02 m w.e. K−1, which is among the smallest magnitudes observed globally. We also identified a high sensitivity to ice albedo, with a decrease of 0.02 having similar effects as a 1 K increase in temperature, and a complex sensitivity to wind speed. Close

• 8. [Article] Lake Macroinvertebrate Assemblages and Relationship With Natural Environment and Tourism Stress in Jiuzhaigou Natural Reserve, China

  With increasing human population and urbanization, tourism in natural reserves and other protected lands is growing. It is critical to monitor and assess the impacts of tourism on ecosystem health. However, ...

  Citation × Citation Citation Abstract Copy Title: Lake Macroinvertebrate Assemblages and Relationship With Natural Environment and Tourism Stress in Jiuzhaigou Natural Reserve, China Author: Cao, Yong, Wang, Beixin, Zhang, Jie, Wang, Lizhu, Pan, Yangdong, Wang, Quanxi, Jian, Daijun, Deng, Guiping Year: 2016 With increasing human population and urbanization, tourism in natural reserves and other protected lands is growing. It is critical to monitor and assess the impacts of tourism on ecosystem health. However, there is a general lack of information on biological communities in natural reserves of developing countries and of tools for assessing human impacts. In the present study, we investigated macroinvertebrate assemblages in nine lakes in Jiuzhaigou Natural Reserve of China. Both benthic (20 dips of D-net) and light-trap samples (2 h) were collected at each lake and all benthic specimens and adults of Ephemeroptera, Plecoptera, and Trichoptera (EPT) were identified and counted. Water temperature and water quality variables were measured on site or in the Lab. Seventy taxa were recorded and dominated by dipterans and caddisflies. Light traps contributed 47% of taxa richness and 66% of EPT richness at the lakes. Detrended Correspondence Analysis showed that water temperature and tourism index were strongly associated with the changes of assemblage composition. Taxa richness and EPT richness calculated for the composite samples (benthic + light trap) were well fit with Poisson generalized linear model (adjusted R2 = 0.83 and 0.85, respectively), generally decreasing with increasing elevation, tourism index, and total-N. Tourism index was ranked as the top predictor for EPT richness based on multiple model weights, and elevation for taxa richness. In comparison, when based on benthic samples, neither of the metrics could be fitted with the seven environmental variables selected. These findings highlight the benefit of combined use of the sampling methods for lake monitoring and offered an analytical guide to developing biological indicators of lake ecosystem health in protected areas. Title: Lake Macroinvertebrate Assemblages and Relationship With Natural Environment and Tourism Stress in Jiuzhaigou Natural Reserve, China Author: Cao, Yong, Wang, Beixin, Zhang, Jie, Wang, Lizhu, Pan, Yangdong, Wang, Quanxi, Jian, Daijun, Deng, Guiping Year: 2016 With increasing human population and urbanization, tourism in natural reserves and other protected lands is growing. It is critical to monitor and assess the impacts of tourism on ecosystem health. However, there is a general lack of information on biological communities in natural reserves of developing countries and of tools for assessing human impacts. In the present study, we investigated macroinvertebrate assemblages in nine lakes in Jiuzhaigou Natural Reserve of China. Both benthic (20 dips of D-net) and light-trap samples (2 h) were collected at each lake and all benthic specimens and adults of Ephemeroptera, Plecoptera, and Trichoptera (EPT) were identified and counted. Water temperature and water quality variables were measured on site or in the Lab. Seventy taxa were recorded and dominated by dipterans and caddisflies. Light traps contributed 47% of taxa richness and 66% of EPT richness at the lakes. Detrended Correspondence Analysis showed that water temperature and tourism index were strongly associated with the changes of assemblage composition. Taxa richness and EPT richness calculated for the composite samples (benthic + light trap) were well fit with Poisson generalized linear model (adjusted R2 = 0.83 and 0.85, respectively), generally decreasing with increasing elevation, tourism index, and total-N. Tourism index was ranked as the top predictor for EPT richness based on multiple model weights, and elevation for taxa richness. In comparison, when based on benthic samples, neither of the metrics could be fitted with the seven environmental variables selected. These findings highlight the benefit of combined use of the sampling methods for lake monitoring and offered an analytical guide to developing biological indicators of lake ecosystem health in protected areas. Close

• 9. [Article] OSMB Final Report, Task 4: Oregon Lake Watch

  The Oregon Lake Watch (OLW) volunteer monitoring program was resurrected after over a decade in hibernation. The new program was designed to educate the public about threats of aquatic invasive species ...

  Citation × Citation Citation Abstract Copy Title: OSMB Final Report, Task 4: Oregon Lake Watch Author: Strecker, Angela L., Miller, Rich, Morgan, Vanessa Year: 2014 The Oregon Lake Watch (OLW) volunteer monitoring program was resurrected after over a decade in hibernation. The new program was designed to educate the public about threats of aquatic invasive species (AIS), provide early detection of AIS invasions, and provide long term water quality data for the better management of Oregon’s lakes and reservoirs. Protocols were created for citizen scientists to survey for AIS, collect temperature and water clarity data, and record the data through an online data entry portal. An OLW website was developed to educate about AIS and provide survey protocols and identification materials to volunteers. AIS surveys were focused on Watch List Species which are selected AIS that have a negative impact on the beneficial uses of our waterbodies. Eighteen volunteers were trained during five sessions conducted in western and central Oregon. Fourteen of the trained volunteers collected data from sixteen waterbodies. Six Watch List species and one other AIS species were observed in four of the waterbodies. The three Watch List Species observed in Salish Pond and one in Olallie Lake were new observations. Temperature measurements indicated a wide range of thermal profiles and Secchi transparency measurement indicated a range of trophic status from oligotrophic to eutrophic. Title: OSMB Final Report, Task 4: Oregon Lake Watch Author: Strecker, Angela L., Miller, Rich, Morgan, Vanessa Year: 2014 The Oregon Lake Watch (OLW) volunteer monitoring program was resurrected after over a decade in hibernation. The new program was designed to educate the public about threats of aquatic invasive species (AIS), provide early detection of AIS invasions, and provide long term water quality data for the better management of Oregon’s lakes and reservoirs. Protocols were created for citizen scientists to survey for AIS, collect temperature and water clarity data, and record the data through an online data entry portal. An OLW website was developed to educate about AIS and provide survey protocols and identification materials to volunteers. AIS surveys were focused on Watch List Species which are selected AIS that have a negative impact on the beneficial uses of our waterbodies. Eighteen volunteers were trained during five sessions conducted in western and central Oregon. Fourteen of the trained volunteers collected data from sixteen waterbodies. Six Watch List species and one other AIS species were observed in four of the waterbodies. The three Watch List Species observed in Salish Pond and one in Olallie Lake were new observations. Temperature measurements indicated a wide range of thermal profiles and Secchi transparency measurement indicated a range of trophic status from oligotrophic to eutrophic. Close

• 10. [Article] Modeling the effectiveness of riparian restoration on stream shading in the Clackamas River Basin

  Rivers and streams within the Clackamas River Basin are not currently meeting water quality standards in terms of temperature. The Clackamas River Basin Council (CRBC) designed a restoration program to ...

  Citation × Citation Citation Abstract Copy Title: Modeling the effectiveness of riparian restoration on stream shading in the Clackamas River Basin Author: Barksdale, Rachel Year: 2017 Rivers and streams within the Clackamas River Basin are not currently meeting water quality standards in terms of temperature. The Clackamas River Basin Council (CRBC) designed a restoration program to address the thermal loading on behalf of Portland General Electric (PGE) in which native trees and shrubs are planted along streams to restore riparian canopy cover. Solar radiation can be blocked by restoring canopy cover and is an effective way to provide shade, as well as providing ancillary environmental benefits such as enhanced wildlife habitat and erosion control. Stream and vegetation data were collected at nine sites to model the increase in shade from the restoration plantings. Using DEQ’s Shade-a-lator model, shade was predicted in future scenarios at 10, 20, and 50 years compared to the current baseline condition. Modeling results suggest increases in shade at each site, which will help to mitigate excessive thermal inputs. The predicted scenarios provide a framework to evaluate the effectiveness of CRBC’s restoration program. Title: Modeling the effectiveness of riparian restoration on stream shading in the Clackamas River Basin Author: Barksdale, Rachel Year: 2017 Rivers and streams within the Clackamas River Basin are not currently meeting water quality standards in terms of temperature. The Clackamas River Basin Council (CRBC) designed a restoration program to address the thermal loading on behalf of Portland General Electric (PGE) in which native trees and shrubs are planted along streams to restore riparian canopy cover. Solar radiation can be blocked by restoring canopy cover and is an effective way to provide shade, as well as providing ancillary environmental benefits such as enhanced wildlife habitat and erosion control. Stream and vegetation data were collected at nine sites to model the increase in shade from the restoration plantings. Using DEQ’s Shade-a-lator model, shade was predicted in future scenarios at 10, 20, and 50 years compared to the current baseline condition. Modeling results suggest increases in shade at each site, which will help to mitigate excessive thermal inputs. The predicted scenarios provide a framework to evaluate the effectiveness of CRBC’s restoration program. Close