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• 1. [Article] Diurnal timing of warmer air under climate change affects magnitude, timing and duration of stream temperature change

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by John Wiley ...

  Citation × Citation Citation Abstract Copy Title: Diurnal timing of warmer air under climate change affects magnitude, timing and duration of stream temperature change Author: Haggerty, Roy, Wondzell, Steven M., Diabat, Mousa To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by John Wiley & Sons Ltd. and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1099-1085. Title: Diurnal timing of warmer air under climate change affects magnitude, timing and duration of stream temperature change Author: Haggerty, Roy, Wondzell, Steven M., Diabat, Mousa To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by John Wiley & Sons Ltd. and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1099-1085. Close

• 2. [Article] Climate change in India inferred from geothermal observations

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Climate change in India inferred from geothermal observations Author: Harris, Robert N., Rao, R. U. M., Roy, Sukanta, Chapman, David S. copyrighted by American Geophysical Union Title: Climate change in India inferred from geothermal observations Author: Harris, Robert N., Rao, R. U. M., Roy, Sukanta, Chapman, David S. copyrighted by American Geophysical Union Close

• 3. [Article] Borehole temperatures and tree rings: Seasonality and estimates of extratropical Northern Hemispheric warming

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Borehole temperatures and tree rings: Seasonality and estimates of extratropical Northern Hemispheric warming Author: Chapman, David S., Harris, Robert N. Copyrighted by American Geophysical Union. Title: Borehole temperatures and tree rings: Seasonality and estimates of extratropical Northern Hemispheric warming Author: Chapman, David S., Harris, Robert N. Copyrighted by American Geophysical Union. Close

• 4. [Article] Snow and the ground temperature record of climate change

  Copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Snow and the ground temperature record of climate change Author: Bartlett, Marshall G., Chapman, David S., Harris, Robert N. Copyrighted by American Geophysical Union Title: Snow and the ground temperature record of climate change Author: Bartlett, Marshall G., Chapman, David S., Harris, Robert N. Copyrighted by American Geophysical Union Close

• 5. [Article] Toward predicting community-level effects of climate: relative temperature scaling of metabolic and ingestion rates

  This is the publisher’s final pdf. The published article is copyrighted by the Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecol. Supplemental Material can be found ...

  Citation × Citation Citation Abstract Copy Title: Toward predicting community-level effects of climate: relative temperature scaling of metabolic and ingestion rates Author: Iles, Alison C. This is the publisher’s final pdf. The published article is copyrighted by the Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecol. Supplemental Material can be found at: http://www.esapubs.org/archive/ecol/E095/231/ Title: Toward predicting community-level effects of climate: relative temperature scaling of metabolic and ingestion rates Author: Iles, Alison C. This is the publisher’s final pdf. The published article is copyrighted by the Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecol. Supplemental Material can be found at: http://www.esapubs.org/archive/ecol/E095/231/ Close

• 6. [Article] Behavioral responses of Atlantic cod to sea temperature changes

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. The published article can be found at: http://onlinelibrary.wiley.com/jo...

  Citation × Citation Citation Abstract Copy Title: Behavioral responses of Atlantic cod to sea temperature changes Author: Freitas, Carla, Ciannelli, Lorenzo, Olsen, Esben Moland, Moland, Even, Knutsen, Halvor This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. The published article can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%292045-7758 Title: Behavioral responses of Atlantic cod to sea temperature changes Author: Freitas, Carla, Ciannelli, Lorenzo, Olsen, Esben Moland, Moland, Even, Knutsen, Halvor This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. The published article can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%292045-7758 Close

• 7. [Article] The effects of temperature on growth, development and settlement of northern rock sole larvae (Lepidopsetta polyxystra)

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by John Wiley ...

  Citation × Citation Citation Abstract Copy Title: The effects of temperature on growth, development and settlement of northern rock sole larvae (Lepidopsetta polyxystra) Author: Haines, Scott, Laurel, Benjamin J., Danley, Courtney To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by John Wiley & Sons Ltd. and can be found at: http://onlinelibrary.wiley.com/journal/10.1111/%28ISSN%291365-2419. Title: The effects of temperature on growth, development and settlement of northern rock sole larvae (Lepidopsetta polyxystra) Author: Haines, Scott, Laurel, Benjamin J., Danley, Courtney To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by John Wiley & Sons Ltd. and can be found at: http://onlinelibrary.wiley.com/journal/10.1111/%28ISSN%291365-2419. Close

• 8. [Article] Climate change on the Colorado Plateau of eastern Utah inferred from borehole temperatures

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Climate change on the Colorado Plateau of eastern Utah inferred from borehole temperatures Author: Chapman, David S., Harris, Robert N. Copyrighted by American Geophysical Union. Title: Climate change on the Colorado Plateau of eastern Utah inferred from borehole temperatures Author: Chapman, David S., Harris, Robert N. Copyrighted by American Geophysical Union. Close

• 9. [Article] Characterizing Rain/snow Partitioning in Mountain Watersheds for Present-day and Future Projected Climates

  Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR.

  Citation × Citation Citation Abstract Copy Title: Characterizing Rain/snow Partitioning in Mountain Watersheds for Present-day and Future Projected Climates Author: Sproles, Eric A., Nolin, Anne W. Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Title: Characterizing Rain/snow Partitioning in Mountain Watersheds for Present-day and Future Projected Climates Author: Sproles, Eric A., Nolin, Anne W. Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Close

• 10. [Article] Effects of Climate Change on Water Quality in the Yaquina Estuary, Oregon

  Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR.

  Citation × Citation Citation Abstract Copy Title: Effects of Climate Change on Water Quality in the Yaquina Estuary, Oregon Author: Chang, Heejun, Steele, Madeline, Brown, Cheryl A., Sharp, Darrin Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Title: Effects of Climate Change on Water Quality in the Yaquina Estuary, Oregon Author: Chang, Heejun, Steele, Madeline, Brown, Cheryl A., Sharp, Darrin Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Close

• 11. [Article] Decadal variations in the global atmospheric land temperatures

  This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/jgr/.

  Citation × Citation Citation Abstract Copy Title: Decadal variations in the global atmospheric land temperatures Author: Rosenfeld, Arthur, Rohde, Robert, Jacobsen, Robert, Muller, Richard A., Wurtele, Jonathan, Curry, Judith, Groom, Donald, Wickham, Charlotte, Perlmutter, Saul This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/jgr/. Title: Decadal variations in the global atmospheric land temperatures Author: Rosenfeld, Arthur, Rohde, Robert, Jacobsen, Robert, Muller, Richard A., Wurtele, Jonathan, Curry, Judith, Groom, Donald, Wickham, Charlotte, Perlmutter, Saul This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/jgr/. Close

• 12. [Article] Potential effects of climate change on Plethodon shermani

  Climate change is a global factor that has been implicated in many behavioral alterations across various species. We speculate and observe the potential responses to the Plethodon shermani mating system ...

  Citation × Citation Citation Abstract Copy Title: Potential effects of climate change on Plethodon shermani Author: Ennis, Kelli N. Climate change is a global factor that has been implicated in many behavioral alterations across various species. We speculate and observe the potential responses to the Plethodon shermani mating system induced from temperature changes, which may affect the ability of P. shermani to rely on external cues for mating season. The courtship rituals of P. shermani have been well-documented; deviations from the expected patterning of behavior was measured via both initiation of and length of time spent in the “tail straddle walk” in addition to insemination success rate. It has been determined that an increase in temperature has implications in more inseminations, while the reverse is apparent for decreased temperature; indicating that climatic changes may lead to an earlier breeding season with warmer temperatures. The effects on our sampling may translate either directly or indirectly to the population, community, and other amphibian-containing ecosystems. We suggest further research that may aid our ability to predict the capacity for amphibians to adjust to climatic changes. Title: Potential effects of climate change on Plethodon shermani Author: Ennis, Kelli N. Climate change is a global factor that has been implicated in many behavioral alterations across various species. We speculate and observe the potential responses to the Plethodon shermani mating system induced from temperature changes, which may affect the ability of P. shermani to rely on external cues for mating season. The courtship rituals of P. shermani have been well-documented; deviations from the expected patterning of behavior was measured via both initiation of and length of time spent in the “tail straddle walk” in addition to insemination success rate. It has been determined that an increase in temperature has implications in more inseminations, while the reverse is apparent for decreased temperature; indicating that climatic changes may lead to an earlier breeding season with warmer temperatures. The effects on our sampling may translate either directly or indirectly to the population, community, and other amphibian-containing ecosystems. We suggest further research that may aid our ability to predict the capacity for amphibians to adjust to climatic changes. Close

• 13. [Article] Thermal controls of Yellowstone cutthroat trout and invasive fishes under climate change

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. The published article is copyrighted by Wiley-Blackwell and can be found at: http:...

  Citation × Citation Citation Abstract Copy Title: Thermal controls of Yellowstone cutthroat trout and invasive fishes under climate change Author: Hostetler, Steven, Gresswell, Robert, Alder, Jay R., Shepard, Bradley, Al-Chokhachy, Robert To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. The published article is copyrighted by Wiley-Blackwell and can be found at: http://onlinelibrary.wiley.com/. Title: Thermal controls of Yellowstone cutthroat trout and invasive fishes under climate change Author: Hostetler, Steven, Gresswell, Robert, Alder, Jay R., Shepard, Bradley, Al-Chokhachy, Robert To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. The published article is copyrighted by Wiley-Blackwell and can be found at: http://onlinelibrary.wiley.com/. Close

• 14. [Article] Satellite Monitoring of Earth’s Surface Temperature: Effects of Land Cover, Disturbance, and a Changing Climate

  Citation × Citation Citation Abstract Copy Title: Satellite Monitoring of Earth’s Surface Temperature: Effects of Land Cover, Disturbance, and a Changing Climate Author: Mildrexler, David J. Title: Satellite Monitoring of Earth’s Surface Temperature: Effects of Land Cover, Disturbance, and a Changing Climate Author: Mildrexler, David J. Close

• 15. [Article] A phenological examination of terrestrial invertebrate abundance at H. J. Andrews Experimental Forest, Oregon

  June 2012

  Citation × Citation Citation Abstract Copy Title: A phenological examination of terrestrial invertebrate abundance at H. J. Andrews Experimental Forest, Oregon Author: Mackereth, Kailan F. June 2012 Title: A phenological examination of terrestrial invertebrate abundance at H. J. Andrews Experimental Forest, Oregon Author: Mackereth, Kailan F. June 2012 Close

• 16. [Article] Modeling Elevation-Dependent Snow Sensitivity to Climate Warming in the Data Sparse Eastern Oregon Cascades

  In the mountains of the Western US, shifts in the timing and magnitude of snow water equivalent (SWE) over the past century are well documented and attributed to climate warming, but the magnitude of sensitivity ...

  Citation × Citation Citation Abstract Copy Title: Modeling Elevation-Dependent Snow Sensitivity to Climate Warming in the Data Sparse Eastern Oregon Cascades Author: Cooper, Matthew Guy In the mountains of the Western US, shifts in the timing and magnitude of snow water equivalent (SWE) over the past century are well documented and attributed to climate warming, but the magnitude of sensitivity depends on elevation. We modeled the spatial distribution of SWE and its sensitivity to climate warming in the 1500 km² Upper Deschutes River Basin, Oregon, with a spatially distributed snowpack energy balance model forced by a gridded meteorological dataset. The forcing data, gridded at a spatial scale of 1/16°, were downscaled to a 100 m spatial-scale digital elevation model using two sets of temperature lapse rates, with and without bias-correction applied prior to downscaling. The bias-correction method adjusted the spatial patterns of temperature and precipitation in the 1/16° gridded data to match 30 arcsecond Parameter Regressions on Independent Slopes Model (PRISM) climate data. During production, the 1/16° temperature data was adjusted for the effect of elevation using a spatially uniform and temporally constant 6.5°C km⁻¹ lapse rate, whereas PRISM adjusts temperature for the effect of elevation using spatially and temporally variable lapse rates that are computed directly from regional weather station data. Thus, bias-correction implicitly adjusted the lapse rates in the 1/16° gridded data to match measured lapse rates. To test the effect of this implicit adjustment of the input data lapse rates vs. adjusting the lapse rates during downscaling, the 30 arcsecond bias-corrected data and 1/16o original data were each downscaled with 1) a spatially uniform and temporally constant 6.5°C km⁻¹ lapse rate, and 2) with monthly varying lapse rates computed from PRISM. Precipitation was downscaled with the same method for each case. This procedure produced four sets of 100 m spatial scale data used as input to the snow model. Model parameters that control empirical estimates of incoming irradiance and the partitioning of precipitation into rain and snow were estimated independently with each dataset to optimize the agreement between modeled and observed SWE. We then modeled the sensitivity (percent change) of basin SWE in response to +2°C and +4°C warming with each of the four downscaled datasets and their respective optimized parameters. Pre-calibration, modeled SWE for the historical climate period differed depending on bias correction and choice of downscaling lapse rates. Post-calibration, modeled SWE for the historical climate period did not differ depending on choice of lapse rates but substantial differences emerged between modeled SWE with the original and bias-corrected forcing data. Inter-forcing dataset differences in modeled SWE during the historical period were largely controlled by differences in estimates of longwave irradiance and temperature between datasets. For the warming scenarios, the SWE sensitivity differed significantly at all elevations between the bias-corrected and original data, but (as in the post-calibration historical period) did not depend on choice of lapse rates. At low to mid elevations, climate change impacts on snow were largely controlled by temperature-driven shifts from snowfall to rainfall, while at high elevations, precipitation variability controlled SWE sensitivity. With just a 2°C increase in temperature, peak snow accumulation occurred 20-30 days earlier and was 20-60% smaller, the length of the snow covered season decreased up to 50 days, and winter rainfall increased by 20-60%. With a 4°C increase, the shifts in timing were roughly doubled and the declines in snow and snowfall increased up to 80%. A 10% increase in precipitation had a negligible impact on basin-integrated declines, indicating that future precipitation variability has little chance of offsetting regional climate warming impacts on snow in the Oregon Cascades. These results highlight the challenges of modeling SWE in data sparse regions, the importance of bias correcting gridded meteorological forcing datasets for hydrologic modeling applications in regions of complex topography, and the strong temperature dependence of snow in the Oregon Cascades. Title: Modeling Elevation-Dependent Snow Sensitivity to Climate Warming in the Data Sparse Eastern Oregon Cascades Author: Cooper, Matthew Guy In the mountains of the Western US, shifts in the timing and magnitude of snow water equivalent (SWE) over the past century are well documented and attributed to climate warming, but the magnitude of sensitivity depends on elevation. We modeled the spatial distribution of SWE and its sensitivity to climate warming in the 1500 km² Upper Deschutes River Basin, Oregon, with a spatially distributed snowpack energy balance model forced by a gridded meteorological dataset. The forcing data, gridded at a spatial scale of 1/16°, were downscaled to a 100 m spatial-scale digital elevation model using two sets of temperature lapse rates, with and without bias-correction applied prior to downscaling. The bias-correction method adjusted the spatial patterns of temperature and precipitation in the 1/16° gridded data to match 30 arcsecond Parameter Regressions on Independent Slopes Model (PRISM) climate data. During production, the 1/16° temperature data was adjusted for the effect of elevation using a spatially uniform and temporally constant 6.5°C km⁻¹ lapse rate, whereas PRISM adjusts temperature for the effect of elevation using spatially and temporally variable lapse rates that are computed directly from regional weather station data. Thus, bias-correction implicitly adjusted the lapse rates in the 1/16° gridded data to match measured lapse rates. To test the effect of this implicit adjustment of the input data lapse rates vs. adjusting the lapse rates during downscaling, the 30 arcsecond bias-corrected data and 1/16o original data were each downscaled with 1) a spatially uniform and temporally constant 6.5°C km⁻¹ lapse rate, and 2) with monthly varying lapse rates computed from PRISM. Precipitation was downscaled with the same method for each case. This procedure produced four sets of 100 m spatial scale data used as input to the snow model. Model parameters that control empirical estimates of incoming irradiance and the partitioning of precipitation into rain and snow were estimated independently with each dataset to optimize the agreement between modeled and observed SWE. We then modeled the sensitivity (percent change) of basin SWE in response to +2°C and +4°C warming with each of the four downscaled datasets and their respective optimized parameters. Pre-calibration, modeled SWE for the historical climate period differed depending on bias correction and choice of downscaling lapse rates. Post-calibration, modeled SWE for the historical climate period did not differ depending on choice of lapse rates but substantial differences emerged between modeled SWE with the original and bias-corrected forcing data. Inter-forcing dataset differences in modeled SWE during the historical period were largely controlled by differences in estimates of longwave irradiance and temperature between datasets. For the warming scenarios, the SWE sensitivity differed significantly at all elevations between the bias-corrected and original data, but (as in the post-calibration historical period) did not depend on choice of lapse rates. At low to mid elevations, climate change impacts on snow were largely controlled by temperature-driven shifts from snowfall to rainfall, while at high elevations, precipitation variability controlled SWE sensitivity. With just a 2°C increase in temperature, peak snow accumulation occurred 20-30 days earlier and was 20-60% smaller, the length of the snow covered season decreased up to 50 days, and winter rainfall increased by 20-60%. With a 4°C increase, the shifts in timing were roughly doubled and the declines in snow and snowfall increased up to 80%. A 10% increase in precipitation had a negligible impact on basin-integrated declines, indicating that future precipitation variability has little chance of offsetting regional climate warming impacts on snow in the Oregon Cascades. These results highlight the challenges of modeling SWE in data sparse regions, the importance of bias correcting gridded meteorological forcing datasets for hydrologic modeling applications in regions of complex topography, and the strong temperature dependence of snow in the Oregon Cascades. Close

• 17. [Article] Soil respiration flux in response to soil temperature, moisture, and pH

  Soil respiration has been identified as one of the largest natural sources of CO₂ to the global carbon cycle. Small alterations in the magnitude of soil respiration can have potentially large effects on ...

  Citation × Citation Citation Abstract Copy Title: Soil respiration flux in response to soil temperature, moisture, and pH Author: Murphy, Bailey Soil respiration has been identified as one of the largest natural sources of CO₂ to the global carbon cycle. Small alterations in the magnitude of soil respiration can have potentially large effects on concentrations of atmospheric CO₂ , making the rate at which respiration occurs of great scientific interest (Martin et al. 2012; Schlesinger & Andrews 2000). This experiment addresses the relationships between the rate at which soil respires and the temperature, moisture content, and pH of the soil. Soil respiration is largely dependent on factors that influence the chemical and microbial properties of the soil, as well as the plant activity. Some of these factors include soil and air temperatures, soil moisture, and soil pH. As our climate changes, these factors have the potential to be altered considerably. Understanding the relationship between these factors and the rate of soil respiration is vital to understanding the implications of an altered climate on soil respiration, and the resulting changes and feedback mechanisms in the amount of CO₂ being added back into the system. WS1 within the H.J. Andrews forest is an ideal setting for this experiment, as the contrast in soil conditions at the various survey plot locations on the North and South facing slopes of the watershed offer an opportunity for comparison of these factors. Title: Soil respiration flux in response to soil temperature, moisture, and pH Author: Murphy, Bailey Soil respiration has been identified as one of the largest natural sources of CO₂ to the global carbon cycle. Small alterations in the magnitude of soil respiration can have potentially large effects on concentrations of atmospheric CO₂ , making the rate at which respiration occurs of great scientific interest (Martin et al. 2012; Schlesinger & Andrews 2000). This experiment addresses the relationships between the rate at which soil respires and the temperature, moisture content, and pH of the soil. Soil respiration is largely dependent on factors that influence the chemical and microbial properties of the soil, as well as the plant activity. Some of these factors include soil and air temperatures, soil moisture, and soil pH. As our climate changes, these factors have the potential to be altered considerably. Understanding the relationship between these factors and the rate of soil respiration is vital to understanding the implications of an altered climate on soil respiration, and the resulting changes and feedback mechanisms in the amount of CO₂ being added back into the system. WS1 within the H.J. Andrews forest is an ideal setting for this experiment, as the contrast in soil conditions at the various survey plot locations on the North and South facing slopes of the watershed offer an opportunity for comparison of these factors. Close

• 18. [Article] Glacial greenhouse-gas fluctuations controlled by ocean circulation changes

  Earth's climate and the concentrations of the atmospheric greenhouse gases carbon dioxide (CO2) and nitrous oxide (N2O) varied strongly on millennial timescales during past glacial periods. Large and rapid ...

  Citation × Citation Citation Abstract Copy Title: Glacial greenhouse-gas fluctuations controlled by ocean circulation changes Author: Schmittner, Andreas, Galbraith, Eric D. Earth's climate and the concentrations of the atmospheric greenhouse gases carbon dioxide (CO2) and nitrous oxide (N2O) varied strongly on millennial timescales during past glacial periods. Large and rapid warming events in Greenland and the North Atlantic were followed by more gradual cooling, and are highly correlated with fluctuations of N2O as recorded in ice cores. Antarctic temperature variations, on the other hand, were smaller and more gradual, showed warming during the Greenland cold phase and cooling while the North Atlantic was warm, and were highly correlated with fluctuations in CO2. Abrupt changes in the Atlantic meridional overturning circulation (AMOC) have often been invoked to explain the physical characteristics of these Dansgaard–Oeschger climate oscillations, but the mechanisms for the greenhouse-gas variations and their linkage to the AMOC have remained unclear. Here we present simulations with a coupled model of glacial climate and biogeochemical cycles, forced only with changes in the AMOC. The model simultaneously reproduces characteristic features of the Dansgaard–Oeschger temperature, as well as CO2 and N2O fluctuations. Despite significant changes in the land carbon inventory, CO2 variations on millennial timescales are dominated by slow changes in the deep ocean inventory of biologically sequestered carbon and are correlated with Antarctic temperature and Southern Ocean stratification. In contrast, N2O co-varies more rapidly with Greenland temperatures owing to fast adjustments of the thermocline oxygen budget. These results suggest that ocean circulation changes were the primary mechanism that drove glacial CO2 and N2O fluctuations on millennial timescales. Title: Glacial greenhouse-gas fluctuations controlled by ocean circulation changes Author: Schmittner, Andreas, Galbraith, Eric D. Earth's climate and the concentrations of the atmospheric greenhouse gases carbon dioxide (CO2) and nitrous oxide (N2O) varied strongly on millennial timescales during past glacial periods. Large and rapid warming events in Greenland and the North Atlantic were followed by more gradual cooling, and are highly correlated with fluctuations of N2O as recorded in ice cores. Antarctic temperature variations, on the other hand, were smaller and more gradual, showed warming during the Greenland cold phase and cooling while the North Atlantic was warm, and were highly correlated with fluctuations in CO2. Abrupt changes in the Atlantic meridional overturning circulation (AMOC) have often been invoked to explain the physical characteristics of these Dansgaard–Oeschger climate oscillations, but the mechanisms for the greenhouse-gas variations and their linkage to the AMOC have remained unclear. Here we present simulations with a coupled model of glacial climate and biogeochemical cycles, forced only with changes in the AMOC. The model simultaneously reproduces characteristic features of the Dansgaard–Oeschger temperature, as well as CO2 and N2O fluctuations. Despite significant changes in the land carbon inventory, CO2 variations on millennial timescales are dominated by slow changes in the deep ocean inventory of biologically sequestered carbon and are correlated with Antarctic temperature and Southern Ocean stratification. In contrast, N2O co-varies more rapidly with Greenland temperatures owing to fast adjustments of the thermocline oxygen budget. These results suggest that ocean circulation changes were the primary mechanism that drove glacial CO2 and N2O fluctuations on millennial timescales. Close

• 19. [Article] CiannelliLorenzoCEOASBehavioralResponseAtlantic.pdf

  Citation × Citation Citation Abstract Copy Title: CiannelliLorenzoCEOASBehavioralResponseAtlantic.pdf Author: Freitas, Carla, Ciannelli, Lorenzo, Olsen, Esben Moland, Moland, Even, Knutsen, Halvor Title: CiannelliLorenzoCEOASBehavioralResponseAtlantic.pdf Author: Freitas, Carla, Ciannelli, Lorenzo, Olsen, Esben Moland, Moland, Even, Knutsen, Halvor Close

• 20. [Article] CiannelliLorenzoCEOASBehavioralResponseAtlanticSupportingInfo.pdf

  Citation × Citation Citation Abstract Copy Title: CiannelliLorenzoCEOASBehavioralResponseAtlanticSupportingInfo.pdf Author: Freitas, Carla, Ciannelli, Lorenzo, Olsen, Esben Moland, Moland, Even, Knutsen, Halvor Title: CiannelliLorenzoCEOASBehavioralResponseAtlanticSupportingInfo.pdf Author: Freitas, Carla, Ciannelli, Lorenzo, Olsen, Esben Moland, Moland, Even, Knutsen, Halvor Close

• 21. [Article] Introducing a sensor to measure budburst and its environmental drivers

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Frontiers Research Foundation. The published article can be found at: http://www.frontiersi...

  Citation × Citation Citation Abstract Copy Title: Introducing a sensor to measure budburst and its environmental drivers Author: Lintz, Heather E., Thomas, Christoph K., Kim, Youngil, Kleinknecht, George J., Still, Christopher J., Niemeier, James J., Salino-Hugg, Michael J., Kruger, Anton This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Frontiers Research Foundation. The published article can be found at: http://www.frontiersin.org/Plant_Science. Title: Introducing a sensor to measure budburst and its environmental drivers Author: Lintz, Heather E., Thomas, Christoph K., Kim, Youngil, Kleinknecht, George J., Still, Christopher J., Niemeier, James J., Salino-Hugg, Michael J., Kruger, Anton This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Frontiers Research Foundation. The published article can be found at: http://www.frontiersin.org/Plant_Science. Close

• 22. [Article] Present-day and future contributions of glacier runoff to summertime flows in a Pacific Northwest watershed: Implications for water resources

  This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/wr/.

  Citation × Citation Citation Abstract Copy Title: Present-day and future contributions of glacier runoff to summertime flows in a Pacific Northwest watershed: Implications for water resources Author: Lewis, Sarah L., Jefferson, Anne, Phillippe, Jeff, Nolin, Anne W. This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/wr/. Title: Present-day and future contributions of glacier runoff to summertime flows in a Pacific Northwest watershed: Implications for water resources Author: Lewis, Sarah L., Jefferson, Anne, Phillippe, Jeff, Nolin, Anne W. This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/wr/. Close

• 23. [Article] Interpretation and design of ocean acidification experiments in upwelling systems in the context of carbonate chemistry co-variation with temperature and oxygen

  This is the publisher’s final pdf. The article is Published by Oxford University Press on behalf of International Council for the Exploration of the Sea 2015. This work is written by (a) US Government ...

  Citation × Citation Citation Abstract Copy Title: Interpretation and design of ocean acidification experiments in upwelling systems in the context of carbonate chemistry co-variation with temperature and oxygen Author: Lucey, Noelle, Evans, Wiley, Mathis, Jeremy T., Hales, Burke, Harvey, Chris J., Newton, Jan, Alin, Simone R., Sabine, Christopher L., Bednaršek, Nina, McElhany, Paul, Feely, Richard A., Reum, Jonathan C. P. This is the publisher’s final pdf. The article is Published by Oxford University Press on behalf of International Council for the Exploration of the Sea 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US. It can be found at: http://icesjms.oxfordjournals.org/ Title: Interpretation and design of ocean acidification experiments in upwelling systems in the context of carbonate chemistry co-variation with temperature and oxygen Author: Lucey, Noelle, Evans, Wiley, Mathis, Jeremy T., Hales, Burke, Harvey, Chris J., Newton, Jan, Alin, Simone R., Sabine, Christopher L., Bednaršek, Nina, McElhany, Paul, Feely, Richard A., Reum, Jonathan C. P. This is the publisher’s final pdf. The article is Published by Oxford University Press on behalf of International Council for the Exploration of the Sea 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US. It can be found at: http://icesjms.oxfordjournals.org/ Close

• 24. [Article] Simulated response of ecosystem processes to climate change in northern California and western Nevada

  In order to investigate potential climate impacts on landscape-scale ecosystem processes, I implemented a dynamic general vegetation model (DGVM) over a large domain in northern California and western ...

  Citation × Citation Citation Abstract Copy Title: Simulated response of ecosystem processes to climate change in northern California and western Nevada Author: McGlinchy, Maureen C. In order to investigate potential climate impacts on landscape-scale ecosystem processes, I implemented a dynamic general vegetation model (DGVM) over a large domain in northern California and western Nevada on a rectangular grid of ca. 800-meter spatial resolution. I used 100 years of observed, monthly climate and nine future climate projections in an attempt to explore the range of possible climate futures in the region. I selected three general circulation models (MIROC3.2(medres), UKMO-HadCM3 and CSIRO-Mk3.0), incorporating a range of 2xCO₂ temperature sensitivity. Each GCM was run through three carbon dioxide emissions scenarios (SRES A2, A1B and B1). For this analysis, I focused the study on the simulated ecological impacts under the three A2 scenarios. Historical observations and future climate scenarios were interpolated to the 800-meter grid by the PRISM model. MC1, a systems-based DGVM, compared favorably to observed data for simulations of vegetation distribution and annual streamflow. MC1 slightly overestimated annual production in the Sierra Nevada and Klamath Mountains and underestimated it in the Coast Range and Eastern Cascades. MC1 displayed a low bias for annual area burned and high bias for pyrogenic emissions. Validation of simulated model output was complicated because MC1 does not consider the effects of land management on ecosystems and the study region is heavily-impacted by development, logging, fire suppression, grazing and pre-European, indigenous land-use and burning. Under all future climate projections, an increase in growing season length and temperature led to the replacement of tundra and subalpine vegetation types with temperate conifer forest. Increased winter minimum temperatures promoted the expansion of mixed needleleaf-broadleaf forest, particularly in the mid-elevations of the Sierra Nevada and in coastal forests. In the MIROC3.2 and HadCM3 scenarios, ecosystem-level net primary productivity (NPP) did not increase with enhanced CO₂ fertilization because production remained limited by water, even though both NPP and water-use-efficiency were increased at the leaf level in proportion to CO₂ concentration. Increases in NPP were projected in CSIRO-Mk3, but increased precipitation and warmer temperatures also increased rates of heterotrophic respiration for no net gain in net ecosystem productivity (NEP). Fire extent and severity increased in all scenarios, mostly driven by significant decreases in mountainous snowpack and earlier snowmelt. Thus, a relatively constant NEP and increased fire emissions produced decreases in total ecosystem carbon across all future scenarios. Projected annual streamflow varied between future climate scenarios and was highly influenced by projected precipitation. In all future simulations, high-elevation mountainous landscapes were highly sensitive to projected changes in climate, largely attributable to an increased growing season and temperature, decreased snowpack and reduced fire return interval. Coastal forests were also highly susceptible to changes in vegetation type and increases in fire. Several sources contribute to uncertainty in MC1, including input datasets, model assumptions, uncertainties in ecosystem science, and questions of scale. Therefore, these results should be considered preliminary, but useful in suggesting a range of plausible ecological futures as we continue to refine model capabilities. Title: Simulated response of ecosystem processes to climate change in northern California and western Nevada Author: McGlinchy, Maureen C. In order to investigate potential climate impacts on landscape-scale ecosystem processes, I implemented a dynamic general vegetation model (DGVM) over a large domain in northern California and western Nevada on a rectangular grid of ca. 800-meter spatial resolution. I used 100 years of observed, monthly climate and nine future climate projections in an attempt to explore the range of possible climate futures in the region. I selected three general circulation models (MIROC3.2(medres), UKMO-HadCM3 and CSIRO-Mk3.0), incorporating a range of 2xCO₂ temperature sensitivity. Each GCM was run through three carbon dioxide emissions scenarios (SRES A2, A1B and B1). For this analysis, I focused the study on the simulated ecological impacts under the three A2 scenarios. Historical observations and future climate scenarios were interpolated to the 800-meter grid by the PRISM model. MC1, a systems-based DGVM, compared favorably to observed data for simulations of vegetation distribution and annual streamflow. MC1 slightly overestimated annual production in the Sierra Nevada and Klamath Mountains and underestimated it in the Coast Range and Eastern Cascades. MC1 displayed a low bias for annual area burned and high bias for pyrogenic emissions. Validation of simulated model output was complicated because MC1 does not consider the effects of land management on ecosystems and the study region is heavily-impacted by development, logging, fire suppression, grazing and pre-European, indigenous land-use and burning. Under all future climate projections, an increase in growing season length and temperature led to the replacement of tundra and subalpine vegetation types with temperate conifer forest. Increased winter minimum temperatures promoted the expansion of mixed needleleaf-broadleaf forest, particularly in the mid-elevations of the Sierra Nevada and in coastal forests. In the MIROC3.2 and HadCM3 scenarios, ecosystem-level net primary productivity (NPP) did not increase with enhanced CO₂ fertilization because production remained limited by water, even though both NPP and water-use-efficiency were increased at the leaf level in proportion to CO₂ concentration. Increases in NPP were projected in CSIRO-Mk3, but increased precipitation and warmer temperatures also increased rates of heterotrophic respiration for no net gain in net ecosystem productivity (NEP). Fire extent and severity increased in all scenarios, mostly driven by significant decreases in mountainous snowpack and earlier snowmelt. Thus, a relatively constant NEP and increased fire emissions produced decreases in total ecosystem carbon across all future scenarios. Projected annual streamflow varied between future climate scenarios and was highly influenced by projected precipitation. In all future simulations, high-elevation mountainous landscapes were highly sensitive to projected changes in climate, largely attributable to an increased growing season and temperature, decreased snowpack and reduced fire return interval. Coastal forests were also highly susceptible to changes in vegetation type and increases in fire. Several sources contribute to uncertainty in MC1, including input datasets, model assumptions, uncertainties in ecosystem science, and questions of scale. Therefore, these results should be considered preliminary, but useful in suggesting a range of plausible ecological futures as we continue to refine model capabilities. Close

• 25. [Article] Climate warming effects on the life cycle of the parasite Ceratomyxa shasta in salmon of the Pacific Northwest

  Aquatic ecosystems continue to be increasingly affected by climate warming. For salmonids in the Pacific Northwest of North America, increasing temperatures pose tighter thermal constraints on their habitat ...

  Citation × Citation Citation Abstract Copy Title: Climate warming effects on the life cycle of the parasite Ceratomyxa shasta in salmon of the Pacific Northwest Author: Chiaramonte, Luciano V. Aquatic ecosystems continue to be increasingly affected by climate warming. For salmonids in the Pacific Northwest of North America, increasing temperatures pose tighter thermal constraints on their habitat use as well as aspects of their individual performance, such as disease resistance. This thesis examines the effect of temperature on the phenology of the Ceratomyxa shasta life cycle, the effect of thermal refugia on disease risk in juvenile salmonids in the Klamath River, CA, and the spatial and temporal distribution of C. shasta in the Willamette River, OR. We developed a biological model that predicts an acceleration of the C. shasta life cycle development due to climate shifts in the Klamath River, resulting in more generations per year and earlier seasonal parasite occurrence. We showed that in early summer the Beaver Creek-Klamath River confluence provides juvenile Chinook and coho salmon an area of lower parasite doses and cooler temperatures than the main stem, thus lessening disease risk. By accelerating the development of C. shasta in its hosts, increasing temperatures will result in earlier parasite transmission to juvenile salmonids and a longer season of infectivity. These fish may find disease refuge at cold tributary inflows to the main stem of the Klamath River in early summer, further adding to the benefit of these important thermal habitats. To determine if similar disease patterns occur in other rivers with the parasite, we described spatial and temporal occurrence of C. shasta in the Willamette River. By collecting weekly water sampling at four sites over 28 months we characterize seasonal and annual differences of parasite abundance, which varies with weekly temperature. We also collected samples along the length of the main stem and its tributaries and identified spatial differences in C. shasta spore densities. Identification of spatial and temporal variation of C. shasta in the Willamette River provides a foundation for understanding future patterns of disease occurrence in this river where conservation of anadromous fisheries is also of concern. This thesis identifies likely responses of C. shasta to climate warming in the Klamath River, with useful application to other rivers in the Pacific Northwest. Title: Climate warming effects on the life cycle of the parasite Ceratomyxa shasta in salmon of the Pacific Northwest Author: Chiaramonte, Luciano V. Aquatic ecosystems continue to be increasingly affected by climate warming. For salmonids in the Pacific Northwest of North America, increasing temperatures pose tighter thermal constraints on their habitat use as well as aspects of their individual performance, such as disease resistance. This thesis examines the effect of temperature on the phenology of the Ceratomyxa shasta life cycle, the effect of thermal refugia on disease risk in juvenile salmonids in the Klamath River, CA, and the spatial and temporal distribution of C. shasta in the Willamette River, OR. We developed a biological model that predicts an acceleration of the C. shasta life cycle development due to climate shifts in the Klamath River, resulting in more generations per year and earlier seasonal parasite occurrence. We showed that in early summer the Beaver Creek-Klamath River confluence provides juvenile Chinook and coho salmon an area of lower parasite doses and cooler temperatures than the main stem, thus lessening disease risk. By accelerating the development of C. shasta in its hosts, increasing temperatures will result in earlier parasite transmission to juvenile salmonids and a longer season of infectivity. These fish may find disease refuge at cold tributary inflows to the main stem of the Klamath River in early summer, further adding to the benefit of these important thermal habitats. To determine if similar disease patterns occur in other rivers with the parasite, we described spatial and temporal occurrence of C. shasta in the Willamette River. By collecting weekly water sampling at four sites over 28 months we characterize seasonal and annual differences of parasite abundance, which varies with weekly temperature. We also collected samples along the length of the main stem and its tributaries and identified spatial differences in C. shasta spore densities. Identification of spatial and temporal variation of C. shasta in the Willamette River provides a foundation for understanding future patterns of disease occurrence in this river where conservation of anadromous fisheries is also of concern. This thesis identifies likely responses of C. shasta to climate warming in the Klamath River, with useful application to other rivers in the Pacific Northwest. Close

• 26. [Article] Simulating past, present, and future changes in ENSO : a model evaluation and data-model comparison

  This thesis presents the results of a formal evaluation of a new AOGCM, GENMOM, demonstrating its ability to simulate present-day climate and ENSO dynamics. The model is applied to simulate climate for ...

  Citation × Citation Citation Abstract Copy Title: Simulating past, present, and future changes in ENSO : a model evaluation and data-model comparison Author: Alder, Jay R. This thesis presents the results of a formal evaluation of a new AOGCM, GENMOM, demonstrating its ability to simulate present-day climate and ENSO dynamics. The model is applied to simulate climate for the Last Glacial Maximum, deglacial, and Holocene time periods. The model output is evaluated against the best available proxy reconstructions in a detailed data-model comparison. ENSO strength is analyzed in seven paleo simulations and compared to coral and laminated lake sediment proxy records to provide an understanding of how ENSO related mechanisms varied in the past and how they vary under increased atmospheric CO₂ forced global warming. The GENMOM simulated present-day is found to be on par with three models used in the IPCC AR4 assessment and is comparable with reanalysis products (e.g, NCEP2). Atmospheric features such as the jet stream structure and major semipermanent sea level pressure centers are well simulated as is the mean planetary-scale wind structure that is needed to produce the correct position of stormtracks. Most ocean surface currents are reproduced except where they are not resolvable at T31 resolution. Overall, GENMOM captures the observed gradients and spatial distributions of annual surface temperature and precipitation and the simulations are on par with other AOGCMs. Deficiencies in the GENMOM present-day simulation include a warm bias in the surface temperature over the southern oceans, a split in the ITCZ and weaker-thanobserved overturning circulation. GENMOM produces a global temperature bias of 0.6 °C. GENMOM is demonstrated to capture ENSO dynamics similar to eight AOGCMs that were evaluated in the IPCC AR4. The Niño 3 - 4 indices have a standard deviation within 0.3 °C of the observations, indicating GENMOM is producing variability in the tropical Pacifc that is comparable to observations. GENMOM produces present-day ENSO events with an average period of 5.6 years, which is within the 2 – 7 range exhibited in the observed historical record. The mid-Holocene (6ka) and Last Glacial Maximum (LGM, 21ka) simulations are compared to the best available proxy reconstructions for sea surface temperature, precipitation and net moisture to ensure the simulations are plausible. This thesis finds that the model is in good agreement over broad spatial scales, with regional discrepancies between the model and proxy data. Coral and laminated lake sediment proxy records indicate mid-Holocene ENSO strength was reduced by 15 - 60%, offering a scenario in which ENSO-related components can be tested in climates different than present-day, thereby providing context for future changes in ENSO. The mid-Holocene simulations exhibit a 20% reduction of ENSO strength, caused by a precession forced enhancement of the Indian summer monsoon, which strengthened ENSO-related Bjerknes feedbacks. ENSO strength in the LGM is weakened by ~25%, which is not found to be caused by changes in equatorial Pacific dynamics but rather mean state cooling that weakens the tropical thermocline. The 2x and 4x simulations have strongly enhanced and more frequent ENSO events caused by disproportionate warming of the eastern Pacific relative to the western Pacific, which weakens the east-west Pacific surface temperature gradient, allowing larger anomalies, and hence ENSO events, to develop. Title: Simulating past, present, and future changes in ENSO : a model evaluation and data-model comparison Author: Alder, Jay R. This thesis presents the results of a formal evaluation of a new AOGCM, GENMOM, demonstrating its ability to simulate present-day climate and ENSO dynamics. The model is applied to simulate climate for the Last Glacial Maximum, deglacial, and Holocene time periods. The model output is evaluated against the best available proxy reconstructions in a detailed data-model comparison. ENSO strength is analyzed in seven paleo simulations and compared to coral and laminated lake sediment proxy records to provide an understanding of how ENSO related mechanisms varied in the past and how they vary under increased atmospheric CO₂ forced global warming. The GENMOM simulated present-day is found to be on par with three models used in the IPCC AR4 assessment and is comparable with reanalysis products (e.g, NCEP2). Atmospheric features such as the jet stream structure and major semipermanent sea level pressure centers are well simulated as is the mean planetary-scale wind structure that is needed to produce the correct position of stormtracks. Most ocean surface currents are reproduced except where they are not resolvable at T31 resolution. Overall, GENMOM captures the observed gradients and spatial distributions of annual surface temperature and precipitation and the simulations are on par with other AOGCMs. Deficiencies in the GENMOM present-day simulation include a warm bias in the surface temperature over the southern oceans, a split in the ITCZ and weaker-thanobserved overturning circulation. GENMOM produces a global temperature bias of 0.6 °C. GENMOM is demonstrated to capture ENSO dynamics similar to eight AOGCMs that were evaluated in the IPCC AR4. The Niño 3 - 4 indices have a standard deviation within 0.3 °C of the observations, indicating GENMOM is producing variability in the tropical Pacifc that is comparable to observations. GENMOM produces present-day ENSO events with an average period of 5.6 years, which is within the 2 – 7 range exhibited in the observed historical record. The mid-Holocene (6ka) and Last Glacial Maximum (LGM, 21ka) simulations are compared to the best available proxy reconstructions for sea surface temperature, precipitation and net moisture to ensure the simulations are plausible. This thesis finds that the model is in good agreement over broad spatial scales, with regional discrepancies between the model and proxy data. Coral and laminated lake sediment proxy records indicate mid-Holocene ENSO strength was reduced by 15 - 60%, offering a scenario in which ENSO-related components can be tested in climates different than present-day, thereby providing context for future changes in ENSO. The mid-Holocene simulations exhibit a 20% reduction of ENSO strength, caused by a precession forced enhancement of the Indian summer monsoon, which strengthened ENSO-related Bjerknes feedbacks. ENSO strength in the LGM is weakened by ~25%, which is not found to be caused by changes in equatorial Pacific dynamics but rather mean state cooling that weakens the tropical thermocline. The 2x and 4x simulations have strongly enhanced and more frequent ENSO events caused by disproportionate warming of the eastern Pacific relative to the western Pacific, which weakens the east-west Pacific surface temperature gradient, allowing larger anomalies, and hence ENSO events, to develop. Close

• 27. [Article] Spring plankton dynamics in the Eastern Bering Sea, 1971-2050: Mechanisms of interannual variability diagnosed with a numerical model

  This is the publisher’s final pdf. The article is copyrighted by American Geophysical Union and published by John Wiley & Sons, Inc. It can be found at: http://agupubs.onlinelibrary.wiley.com/agu/jgr/j...

  Citation × Citation Citation Abstract Copy Title: Spring plankton dynamics in the Eastern Bering Sea, 1971-2050: Mechanisms of interannual variability diagnosed with a numerical model Author: Sambrotto, Raymond N., Zhang, Jinlun, Lomas, Michael W., Sherr, Barry, Stoecker, Diane, Campbell, Robert G., Sherr, Evelyn, Lessard, Evelyn J., Banas, Neil S., Ashjian, Carin This is the publisher’s final pdf. The article is copyrighted by American Geophysical Union and published by John Wiley & Sons, Inc. It can be found at: http://agupubs.onlinelibrary.wiley.com/agu/jgr/journal/10.1002/%28ISSN%292169-9291/ Title: Spring plankton dynamics in the Eastern Bering Sea, 1971-2050: Mechanisms of interannual variability diagnosed with a numerical model Author: Sambrotto, Raymond N., Zhang, Jinlun, Lomas, Michael W., Sherr, Barry, Stoecker, Diane, Campbell, Robert G., Sherr, Evelyn, Lessard, Evelyn J., Banas, Neil S., Ashjian, Carin This is the publisher’s final pdf. The article is copyrighted by American Geophysical Union and published by John Wiley & Sons, Inc. It can be found at: http://agupubs.onlinelibrary.wiley.com/agu/jgr/journal/10.1002/%28ISSN%292169-9291/ Close

• 28. [Article] Introducing and validating a high-throughput bud break sensor

  Bud break is a key adaptive trait that can help us understand how plants respond to a changing climate from the molecular to landscape scale. Despite this, acquisition of bud break data is currently constrained ...

  Citation × Citation Citation Abstract Copy Title: Introducing and validating a high-throughput bud break sensor Author: Kleinknecht, George J. Bud break is a key adaptive trait that can help us understand how plants respond to a changing climate from the molecular to landscape scale. Despite this, acquisition of bud break data is currently constrained by cost, scale, and a lack of information at the plant scale on the environmental stimuli that precede and cause bud dormancy to release. Additionally, to date, little effort has been devoted to phenotyping plants in nature owing to the challenge of controlling for environmental variation to isolate genomic effects on plant phenotype. Notwithstanding, natural selection operates on natural populations, and investigation of adaptive phenotypes in situ is warranted and can validate results from controlled laboratory experiments. In order to identify genomic effects on individual plant phenotypes in nature, environmental drivers must be concurrently measured and characterized. Here, we innovated and evaluated a sensor to meet these requirements for temperate woody plants. It was designed for use on a tree branch to measure the timing of bud break together with its key environmental drivers, temperature and day length. Specifically, we evaluated the sensor through independent corroboration with time-lapse photography and a suite of environmental sampling instruments. We also tested whether the presence of the device itself on a branch influenced the timing of bud break. Our results indicated the following: the bud break sensor's digital thermometer closely approximated a thermocouple touching plant tissue; the photoperiod detector measured ambient light with the same accuracy as time lapse photography; the phenology sensor accurately detected the timing of bud break; and the sensor itself did not influence bud phenology. Future use of the sensor can help galvanize a new field of study, landscape phenomics, or high-throughput phenotyping of organisms at the landscape level for integration with landscape genomics among other potential applications and disciplines. Title: Introducing and validating a high-throughput bud break sensor Author: Kleinknecht, George J. Bud break is a key adaptive trait that can help us understand how plants respond to a changing climate from the molecular to landscape scale. Despite this, acquisition of bud break data is currently constrained by cost, scale, and a lack of information at the plant scale on the environmental stimuli that precede and cause bud dormancy to release. Additionally, to date, little effort has been devoted to phenotyping plants in nature owing to the challenge of controlling for environmental variation to isolate genomic effects on plant phenotype. Notwithstanding, natural selection operates on natural populations, and investigation of adaptive phenotypes in situ is warranted and can validate results from controlled laboratory experiments. In order to identify genomic effects on individual plant phenotypes in nature, environmental drivers must be concurrently measured and characterized. Here, we innovated and evaluated a sensor to meet these requirements for temperate woody plants. It was designed for use on a tree branch to measure the timing of bud break together with its key environmental drivers, temperature and day length. Specifically, we evaluated the sensor through independent corroboration with time-lapse photography and a suite of environmental sampling instruments. We also tested whether the presence of the device itself on a branch influenced the timing of bud break. Our results indicated the following: the bud break sensor's digital thermometer closely approximated a thermocouple touching plant tissue; the photoperiod detector measured ambient light with the same accuracy as time lapse photography; the phenology sensor accurately detected the timing of bud break; and the sensor itself did not influence bud phenology. Future use of the sensor can help galvanize a new field of study, landscape phenomics, or high-throughput phenotyping of organisms at the landscape level for integration with landscape genomics among other potential applications and disciplines. Close

• 29. [Article] Snowpack characteristics in a post-wildfire environment: an examination of the Shadow Lake fire region Oregon Cascades

  As global temperatures continue to rise there has been an increase in forest fire frequency and severity. With larger areas of forest being burned it is increasingly important to understand how forest ...

  Citation × Citation Citation Abstract Copy Title: Snowpack characteristics in a post-wildfire environment: an examination of the Shadow Lake fire region Oregon Cascades Author: Roses, Tyler As global temperatures continue to rise there has been an increase in forest fire frequency and severity. With larger areas of forest being burned it is increasingly important to understand how forest fires effect snow processes. Previous research shows that burned areas will accumulate more snow and that this snow will melt much faster when compared to unburned forests. These conditions can lead to high magnitude stream flows which have broad implications for reservoir managers, flood control, and groundwater recharge. This project studied the post-wildfire effects on accumulation and ablation rates of snowpack in a recently burned forest. The Shadow Lake fire in the Mt. Washington Wilderness near Sisters, Oregon burned over 10,000 acres in the late summer of 2011. In situ snowpack measurements were made in both burned and unburned forest areas. Graphs were created in order to analyze these areas for similarities and differences between snow depth, density, temperature, and concentration of burned and unburned forest debris (bark, needles, etc.) within the snowpack. Title: Snowpack characteristics in a post-wildfire environment: an examination of the Shadow Lake fire region Oregon Cascades Author: Roses, Tyler As global temperatures continue to rise there has been an increase in forest fire frequency and severity. With larger areas of forest being burned it is increasingly important to understand how forest fires effect snow processes. Previous research shows that burned areas will accumulate more snow and that this snow will melt much faster when compared to unburned forests. These conditions can lead to high magnitude stream flows which have broad implications for reservoir managers, flood control, and groundwater recharge. This project studied the post-wildfire effects on accumulation and ablation rates of snowpack in a recently burned forest. The Shadow Lake fire in the Mt. Washington Wilderness near Sisters, Oregon burned over 10,000 acres in the late summer of 2011. In situ snowpack measurements were made in both burned and unburned forest areas. Graphs were created in order to analyze these areas for similarities and differences between snow depth, density, temperature, and concentration of burned and unburned forest debris (bark, needles, etc.) within the snowpack. Close

• 30. [Article] Relaxation of central Arctic Ocean hydrography to pre-1990s climatology

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Relaxation of central Arctic Ocean hydrography to pre-1990s climatology Author: Smethie, W., Morison, J., Kikuchi, T., Steele, M., Falkner, Kelly Copyrighted by American Geophysical Union. Title: Relaxation of central Arctic Ocean hydrography to pre-1990s climatology Author: Smethie, W., Morison, J., Kikuchi, T., Steele, M., Falkner, Kelly Copyrighted by American Geophysical Union. Close

• 31. [Article] The impact of El Niño events on the pelagic food chain in the northern California Current

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by John Wiley ...

  Citation × Citation Citation Abstract Copy Title: The impact of El Niño events on the pelagic food chain in the northern California Current Author: Rykaczewski, Ryan R., Peterson, William T., Fisher, Jennifer L. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by John Wiley & Sons, Ltd. and can be found at: http://onlinelibrary.wiley.com/journal/10.1111/%28ISSN%291365-2486 Title: The impact of El Niño events on the pelagic food chain in the northern California Current Author: Rykaczewski, Ryan R., Peterson, William T., Fisher, Jennifer L. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by John Wiley & Sons, Ltd. and can be found at: http://onlinelibrary.wiley.com/journal/10.1111/%28ISSN%291365-2486 Close

• 32. [Article] The consequences of photoperiodism for organisms in new climates

  This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecap

  Citation × Citation Citation Abstract Copy Title: The consequences of photoperiodism for organisms in new climates Author: Grevstad, Fritzi S., Coop, Leonard B. This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecap Title: The consequences of photoperiodism for organisms in new climates Author: Grevstad, Fritzi S., Coop, Leonard B. This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecap Close

• 33. [Article] Hydrologic Response to Climate Change in the Sprague River Basin, Oregon

  Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR.

  Citation × Citation Citation Abstract Copy Title: Hydrologic Response to Climate Change in the Sprague River Basin, Oregon Author: Hay, Lauren E., Markstrom, Steven L., Risley, John Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Title: Hydrologic Response to Climate Change in the Sprague River Basin, Oregon Author: Hay, Lauren E., Markstrom, Steven L., Risley, John Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Close

• 34. [Article] Impacts of Swiss needle cast on overstory Douglas-fir forests of the western Oregon Coast Range

  Article appears in Forest Ecology and Management (http://www.elsevier.com/wps/find/journaldescription.cws_home/503310/description#description) and is copyrighted by Elsevier.

  Citation × Citation Citation Abstract Copy Title: Impacts of Swiss needle cast on overstory Douglas-fir forests of the western Oregon Coast Range Author: Stone, Jeffrey K., Black, Bryan A., Shaw, David C. Article appears in Forest Ecology and Management (http://www.elsevier.com/wps/find/journaldescription.cws_home/503310/description#description) and is copyrighted by Elsevier. Title: Impacts of Swiss needle cast on overstory Douglas-fir forests of the western Oregon Coast Range Author: Stone, Jeffrey K., Black, Bryan A., Shaw, David C. Article appears in Forest Ecology and Management (http://www.elsevier.com/wps/find/journaldescription.cws_home/503310/description#description) and is copyrighted by Elsevier. Close

• 35. [Article] Carbon isotopes show snowpack acts as a valuable moisture subsidy to mountain forests in the Oregon Cascades

  This study examines climatological influences, particularly that of snowpack, on tree growth and stable carbon isotope discrimination (Δ¹³C) from ~1980 to 2013 at two sites located in the upper reaches ...

  Citation × Citation Citation Abstract Copy Title: Carbon isotopes show snowpack acts as a valuable moisture subsidy to mountain forests in the Oregon Cascades Author: Ratcliff, Christopher J. This study examines climatological influences, particularly that of snowpack, on tree growth and stable carbon isotope discrimination (Δ¹³C) from ~1980 to 2013 at two sites located in the upper reaches of the McKenzie River watershed of the Oregon Cascade Mountains. We tested the use of Δ¹³C values from latewood, corroborated by tree-ring width chronologies as precipitation proxies to develop correlations between moisture stress and climate variables. Tree species at each site included Douglas-fir and mountain hemlock. Interpolated meteorological and snowpack data included snow water equivalent (SWE), precipitation, atmospheric temperature, vapor pressure deficit (VPD), relative humidity (RH), and a metric estimating growing season length. Significant correlations between latewood Δ¹³C and winter SWE at each site indicated the importance of winter snowpack to our selected tree species (r = 0.35, r = 0.43). Late summer precipitation and relative humidity (RH) were also significantly correlated with Δ¹³C (r = 0.49, r = 0.46; r = 0.43, r = 0.44). High correlations at both sites reinforced that late summer VPD was the primary driver of Δ¹³C (r = - 0.67, r = -0.61), which is often associated with moisture stress. This was further supported by correlations between air temperature and Δ¹³C (r = -0.46, r = -0.47), which drives much of the variation in VPD. Growing season length also showed significance in mountain hemlocks at the site with longer average snowpack (r = -0.22, r = -0.44). Moisture supplied by spring snow melt is a seasonably limited resource, nonetheless both sites clearly showed that snowpack acts as a valuable moisture subsidy to coniferous mountain forests in the Oregon Cascades. This study acts as a useful case study for future investigations into the relationship between snowpack and forest health in the Pacific North West. Title: Carbon isotopes show snowpack acts as a valuable moisture subsidy to mountain forests in the Oregon Cascades Author: Ratcliff, Christopher J. This study examines climatological influences, particularly that of snowpack, on tree growth and stable carbon isotope discrimination (Δ¹³C) from ~1980 to 2013 at two sites located in the upper reaches of the McKenzie River watershed of the Oregon Cascade Mountains. We tested the use of Δ¹³C values from latewood, corroborated by tree-ring width chronologies as precipitation proxies to develop correlations between moisture stress and climate variables. Tree species at each site included Douglas-fir and mountain hemlock. Interpolated meteorological and snowpack data included snow water equivalent (SWE), precipitation, atmospheric temperature, vapor pressure deficit (VPD), relative humidity (RH), and a metric estimating growing season length. Significant correlations between latewood Δ¹³C and winter SWE at each site indicated the importance of winter snowpack to our selected tree species (r = 0.35, r = 0.43). Late summer precipitation and relative humidity (RH) were also significantly correlated with Δ¹³C (r = 0.49, r = 0.46; r = 0.43, r = 0.44). High correlations at both sites reinforced that late summer VPD was the primary driver of Δ¹³C (r = - 0.67, r = -0.61), which is often associated with moisture stress. This was further supported by correlations between air temperature and Δ¹³C (r = -0.46, r = -0.47), which drives much of the variation in VPD. Growing season length also showed significance in mountain hemlocks at the site with longer average snowpack (r = -0.22, r = -0.44). Moisture supplied by spring snow melt is a seasonably limited resource, nonetheless both sites clearly showed that snowpack acts as a valuable moisture subsidy to coniferous mountain forests in the Oregon Cascades. This study acts as a useful case study for future investigations into the relationship between snowpack and forest health in the Pacific North West. Close

• 36. [Article] Soil-Climate Feedbacks: Understanding the Controls and Ecosystem Responses of the Carbon Cycle Under a Changing Climate

  Soil organic matter (SOM) decomposition and formation is an important climate feedback, with the potential to amplify or offset climate forcing. To understand the fate of soil carbon (C) stores and fluxes ...

  Citation × Citation Citation Abstract Copy Title: Soil-Climate Feedbacks: Understanding the Controls and Ecosystem Responses of the Carbon Cycle Under a Changing Climate Author: Reynolds, Lorien Year: 2016 Soil organic matter (SOM) decomposition and formation is an important climate feedback, with the potential to amplify or offset climate forcing. To understand the fate of soil carbon (C) stores and fluxes (i.e., soil respiration) under future climate it is necessary to investigate responses across spatial and temporal scales, from the ecosystem to the molecular level, from diurnal to decadal trends. Moreover, it is important to question the assumptions and paradigms that underlie apparently paradoxical evidence to reveal the true nature of soil-climate feedbacks. My dissertation includes research into the response of soil respiration in Pacific Northwest prairies to warming and wetting along a natural regional climate gradient (Chapter II), and then delves deeper into the mechanisms underlying SOM decomposition and formation, examining the temperature sensitivity of SOM decomposition of prairie soils that were experimentally warmed for ~2 yr, and a forest soil in which litter-inputs were manipulation for 20 yr (Chapter III), and finally testing soil C cycling dynamics, including mineral-associated C pools, decomposition dynamics, and the molecular nature of SOM itself, under litter-manipulation in order to understand the controls on SOM formation and mineralization (Chapter IV). This dissertation includes previously published and unpublished coauthored material; see the individual chapters for a list of co-authors, and description of contributions. Title: Soil-Climate Feedbacks: Understanding the Controls and Ecosystem Responses of the Carbon Cycle Under a Changing Climate Author: Reynolds, Lorien Year: 2016 Soil organic matter (SOM) decomposition and formation is an important climate feedback, with the potential to amplify or offset climate forcing. To understand the fate of soil carbon (C) stores and fluxes (i.e., soil respiration) under future climate it is necessary to investigate responses across spatial and temporal scales, from the ecosystem to the molecular level, from diurnal to decadal trends. Moreover, it is important to question the assumptions and paradigms that underlie apparently paradoxical evidence to reveal the true nature of soil-climate feedbacks. My dissertation includes research into the response of soil respiration in Pacific Northwest prairies to warming and wetting along a natural regional climate gradient (Chapter II), and then delves deeper into the mechanisms underlying SOM decomposition and formation, examining the temperature sensitivity of SOM decomposition of prairie soils that were experimentally warmed for ~2 yr, and a forest soil in which litter-inputs were manipulation for 20 yr (Chapter III), and finally testing soil C cycling dynamics, including mineral-associated C pools, decomposition dynamics, and the molecular nature of SOM itself, under litter-manipulation in order to understand the controls on SOM formation and mineralization (Chapter IV). This dissertation includes previously published and unpublished coauthored material; see the individual chapters for a list of co-authors, and description of contributions. Close

• 37. [Article] Climate and streamflow trends in the Columbia River basin: evidence for ecological and engineering resilience to climate change

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Taylor & Francis and can be found at: http://www.tandfonline.com/toc/tato20/cur...

  Citation × Citation Citation Abstract Copy Title: Climate and streamflow trends in the Columbia River basin: evidence for ecological and engineering resilience to climate change Author: Hatcher, Kendra L., Jones, Julia A. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Taylor & Francis and can be found at: http://www.tandfonline.com/toc/tato20/current#.UkoG0XfVGHc. Title: Climate and streamflow trends in the Columbia River basin: evidence for ecological and engineering resilience to climate change Author: Hatcher, Kendra L., Jones, Julia A. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Taylor & Francis and can be found at: http://www.tandfonline.com/toc/tato20/current#.UkoG0XfVGHc. Close

• 38. [Article] Predicting the effects of climate change : effects of thermal stress on seaweeds in the Galapagos rocky intertidal

  Because global warming is predicted to increase the severity of El Niño events in the future, understanding how warmer temperatures affect seaweed growth and the animals associated with seaweeds is important ...

  Citation × Citation Citation Abstract Copy Title: Predicting the effects of climate change : effects of thermal stress on seaweeds in the Galapagos rocky intertidal Author: Harris, Alyssa L. Because global warming is predicted to increase the severity of El Niño events in the future, understanding how warmer temperatures affect seaweed growth and the animals associated with seaweeds is important for predicting how marine ecosystems will change. The Galapagos Islands of Ecuador are considered a living laboratory for studying climate change and served as the experimental site for this study. An artificially induced average increase in temperature by 1.45°C significantly decreased seaweed biomass in the intertidal of Tortuga Bay, Santa Cruz Island. The experiment utilized a block design with six treatments. Treatments consisted of 15cm x 15cm black (warm) and white (cool) plates to cause differential thermal stress, cross-factored with herbivore exclusion cages to study the effects of grazing, and a natural substratum control. Thermal stress (plate color) and grazing were both significant factors reducing seaweed biomass. Abundance, richness, and diversity of invertebrate animals living among the seaweeds showed declines in warmer treatments. Effects on small animals could reflect intolerance to thermal stress, loss of habitat (seaweed), or both, and future studies should investigate these factors. These results indicate that warmer conditions due to human induced climate change can decrease seaweed growth and affect animals that rely on seaweeds for food or habitat, possibly including the Galapagos marine iguana. Insight from the Galapagos might help predict seaweed response to climate change in other regions including the temperate Pacific Northwest. Title: Predicting the effects of climate change : effects of thermal stress on seaweeds in the Galapagos rocky intertidal Author: Harris, Alyssa L. Because global warming is predicted to increase the severity of El Niño events in the future, understanding how warmer temperatures affect seaweed growth and the animals associated with seaweeds is important for predicting how marine ecosystems will change. The Galapagos Islands of Ecuador are considered a living laboratory for studying climate change and served as the experimental site for this study. An artificially induced average increase in temperature by 1.45°C significantly decreased seaweed biomass in the intertidal of Tortuga Bay, Santa Cruz Island. The experiment utilized a block design with six treatments. Treatments consisted of 15cm x 15cm black (warm) and white (cool) plates to cause differential thermal stress, cross-factored with herbivore exclusion cages to study the effects of grazing, and a natural substratum control. Thermal stress (plate color) and grazing were both significant factors reducing seaweed biomass. Abundance, richness, and diversity of invertebrate animals living among the seaweeds showed declines in warmer treatments. Effects on small animals could reflect intolerance to thermal stress, loss of habitat (seaweed), or both, and future studies should investigate these factors. These results indicate that warmer conditions due to human induced climate change can decrease seaweed growth and affect animals that rely on seaweeds for food or habitat, possibly including the Galapagos marine iguana. Insight from the Galapagos might help predict seaweed response to climate change in other regions including the temperate Pacific Northwest. Close

• 39. [Article] A study of public perceptions of energy issues and technology for the development of engineering education activities

  Human use of fossil fuels has caused a dramatic shift in the earth’s environment, with global temperatures rising and ecosystem health declining. The need for the human species to reduce our reliance on ...

  Citation × Citation Citation Abstract Copy Title: A study of public perceptions of energy issues and technology for the development of engineering education activities Author: Hinkle, Nathan Human use of fossil fuels has caused a dramatic shift in the earth’s environment, with global temperatures rising and ecosystem health declining. The need for the human species to reduce our reliance on fossil fuels is apparent. This will be achieved by replacing conventional energy resources with sustainable alternatives, and by reducing overall energy consumption on both a personal and global scale. Citizens must be engaged and informed on energy issues in order to achieve the drastic changes required. This project studied public perceptions and understandings of energy issues and technologies through survey research, and developed five new engineering education activities to address knowledge gaps identified in the survey. These activities have been conducted with groups of students at OSU, revised based on student feedback, and will be made available to educators online. Title: A study of public perceptions of energy issues and technology for the development of engineering education activities Author: Hinkle, Nathan Human use of fossil fuels has caused a dramatic shift in the earth’s environment, with global temperatures rising and ecosystem health declining. The need for the human species to reduce our reliance on fossil fuels is apparent. This will be achieved by replacing conventional energy resources with sustainable alternatives, and by reducing overall energy consumption on both a personal and global scale. Citizens must be engaged and informed on energy issues in order to achieve the drastic changes required. This project studied public perceptions and understandings of energy issues and technologies through survey research, and developed five new engineering education activities to address knowledge gaps identified in the survey. These activities have been conducted with groups of students at OSU, revised based on student feedback, and will be made available to educators online. Close

• 40. [Article] A method for remotely monitoring glaciers with regional application to the Pacific Northwest

  An integrative method for monitoring glacier geometry change and mass balance is presented and applied to the Pacific Northwest, USA. Acting as a baseline for interpretation of future changes in glacier ...

  Citation × Citation Citation Abstract Copy Title: A method for remotely monitoring glaciers with regional application to the Pacific Northwest Author: Medley, Brooke An integrative method for monitoring glacier geometry change and mass balance is presented and applied to the Pacific Northwest, USA. Acting as a baseline for interpretation of future changes in glacier size and shape, we first derive a new inventory of regional glacier cover using remotely sensed data. To investigate current climate controls on glacier health, we next model glacier mass balance for select glaciers, incorporating glacier hypsometry results from our new remotely derived inventory. Model results are then used to interpret climate-glacier interactions through sensitivity analysis and the future impacts on glacier geometry. These steps when taken together create a method for remote monitoring of glacier health and dynamics that can be replicated globally. Inventory results derived from the Advanced Spaceborne Thermal Emission and Reflection Radiometer imagery for the Pacific Northwest indicate that both the North Cascades National Park (99.0 ± 5.0 km2) and the Cascade volcanoes of Washington and Oregon (96.0 ± 4.8 km2) contain similar ice coverage while glaciers of the Olympic Mountains account for only 37.3 ± 1.9 km2. Additionally, significant semi-annual variations in glacier coverage on the Cascade volcanoes highlight the need to consider recent mass balance variations when selecting satellite data for glacier inventorying. Modeling results provided insight into climate-glacier interactions. Model results from the study glaciers show a recent strengthening of the relationship between summer balance and the El Niño/Southern Oscillation (ENSO) from the mid-1980s to the present. The correlation strengthening between ENSO and summer temperatures around 1985 is manifested in our results through enhanced summer melt. However, the influence of the Pacific Decadal Oscillation (PDO) on balance fluctuations is more ambiguous, as the recent 1976/77 shift into a warm phase is weakly distinguishable at only one study glacier. Glacier sensitivity estimates for a 1° C rise in temperature range from -0.73 to -1.09 mw.e., decreasing with latitude; however, no discernible pattern of precipitation sensitivity exists. At South Cascade glacier, a 30% increase in winter precipitation could offset a 1° C rise in temperature. Glaciers further south require a >40% increase in winter precipitation to remain in balance. However, South Cascade is the only glacier of the four study glaciers that could not exist under a 2° C warming scenario as its accumulation area occupies very low elevations. We postulate that the sensitivity of South Cascade glacier does not change as rapidly as those of the remaining three glaciers as the glacier retreats, making it the most vulnerable to climate change. Title: A method for remotely monitoring glaciers with regional application to the Pacific Northwest Author: Medley, Brooke An integrative method for monitoring glacier geometry change and mass balance is presented and applied to the Pacific Northwest, USA. Acting as a baseline for interpretation of future changes in glacier size and shape, we first derive a new inventory of regional glacier cover using remotely sensed data. To investigate current climate controls on glacier health, we next model glacier mass balance for select glaciers, incorporating glacier hypsometry results from our new remotely derived inventory. Model results are then used to interpret climate-glacier interactions through sensitivity analysis and the future impacts on glacier geometry. These steps when taken together create a method for remote monitoring of glacier health and dynamics that can be replicated globally. Inventory results derived from the Advanced Spaceborne Thermal Emission and Reflection Radiometer imagery for the Pacific Northwest indicate that both the North Cascades National Park (99.0 ± 5.0 km2) and the Cascade volcanoes of Washington and Oregon (96.0 ± 4.8 km2) contain similar ice coverage while glaciers of the Olympic Mountains account for only 37.3 ± 1.9 km2. Additionally, significant semi-annual variations in glacier coverage on the Cascade volcanoes highlight the need to consider recent mass balance variations when selecting satellite data for glacier inventorying. Modeling results provided insight into climate-glacier interactions. Model results from the study glaciers show a recent strengthening of the relationship between summer balance and the El Niño/Southern Oscillation (ENSO) from the mid-1980s to the present. The correlation strengthening between ENSO and summer temperatures around 1985 is manifested in our results through enhanced summer melt. However, the influence of the Pacific Decadal Oscillation (PDO) on balance fluctuations is more ambiguous, as the recent 1976/77 shift into a warm phase is weakly distinguishable at only one study glacier. Glacier sensitivity estimates for a 1° C rise in temperature range from -0.73 to -1.09 mw.e., decreasing with latitude; however, no discernible pattern of precipitation sensitivity exists. At South Cascade glacier, a 30% increase in winter precipitation could offset a 1° C rise in temperature. Glaciers further south require a >40% increase in winter precipitation to remain in balance. However, South Cascade is the only glacier of the four study glaciers that could not exist under a 2° C warming scenario as its accumulation area occupies very low elevations. We postulate that the sensitivity of South Cascade glacier does not change as rapidly as those of the remaining three glaciers as the glacier retreats, making it the most vulnerable to climate change. Close

• 41. [Article] Potential effects of climate change and fire management on fire behavior and vegetation patterns on an east Cascades landscape

  Climate exerts considerable control on wildfire regimes, and climate and wildfire are both major drivers of forest growth and succession in interior Northwest forests. Estimating potential response of ...

  Citation × Citation Citation Abstract Copy Title: Potential effects of climate change and fire management on fire behavior and vegetation patterns on an east Cascades landscape Author: Greaves, Heather E. Climate exerts considerable control on wildfire regimes, and climate and wildfire are both major drivers of forest growth and succession in interior Northwest forests. Estimating potential response of these landscapes to anticipated changes in climate helps researchers and land managers understand and mitigate impacts of climate change on important ecological and economic resources. Spatially explicit, mechanistic computer simulation models are powerful tools that permit researchers to incorporate climate and disturbance events along with vegetation physiology and phenology to explore complex potential effects of climate change over wide spatial and temporal scales. In this thesis, I used the simulation model FireBGCv2 to characterize potential response of fire, vegetation, and landscape dynamics to a range of possible future climate and fire management scenarios. The simulation landscape (~43,000 hectares) is part of Deschutes National Forest, which is located at the interface of maritime and continental climates and is known for its beauty and ecological diversity. Simulation scenarios included all combinations of +0°C, +3°C, and +6°C of warming; +10%, ±0%, and -10% historical precipitation; and 10% and 90% fire suppression, and were run for 500 years. To characterize fire dynamics, I investigated how mean fire frequency, intensity, and fuel loadings changed over time in all scenarios, and how fire and tree mortality interacted over time. To explore vegetation and landscape dynamics, I described the distribution and spatial arrangement of vegetation types and forest successional stages on the landscape, and used a nonmetric multidimensional scaling (NMS) ordination to holistically evaluate overall similarity of composition, structure, and landscape pattern among all simulation scenarios over time. Changes in precipitation had little effect on fire characteristics or vegetation and landscape characteristics, indicating that simulated precipitation changes were not sufficient to significantly affect vegetation moisture stress or fire behavior on this landscape. Current heavy fuel loads controlled early fire dynamics, with high mean fire intensities occurring early in all simulations. Increases in fire frequency accompanied all temperature increases, leading to decreasing fuel loads and fire intensities over time in warming scenarios. With no increase in temperature or in fire frequency, high fire intensities and heavier fuel loads were sustained. Over time, more fire associated with warming or less fire suppression increased the percentage of the landscape occupied by non-forest and fire-sensitive early seral forest successional stages, which tended to increase the percentage of fire area burning at high severity (in terms of tree mortality). This fire-vegetation relationship may reflect a return to a more historical range of conditions on this landscape. Higher temperatures and fire frequency led to significant spatial migration of forest types across the landscape, with communities at the highest and lowest elevations particularly affected. Warming led to an upslope shift of warm mixed conifer and ponderosa pine (Pinus ponderosa) forests, severely contracting (under 3° of warming) or eliminating (under 6° of warming) area dominated by mountain hemlock (Tsuga mertensiana) and cool, wet conifer forest in the high western portion of the landscape. In lower elevations, warming and fire together contributed to significant expansion of open (<10% tree canopy cover) forest and grass- and shrubland. The compositional changes and spatial shifts simulated in the warming scenarios suggest that climate change is likely to significantly affect forests on this landscape. Warming and associated fire also tended to increase heterogeneity of forest structural stages and landscape pattern, resulting in a more diverse distribution of structural stages, especially in lower elevations, and a more divided landscape of smaller forest stands. The NMS ordination emphasized the dissimilarity between the severe +6° scenarios and the other two temperature scenarios. The +0° and +3° scenarios differed from each other in composition (mainly because cool forest was lost in the +3° scenarios), but within a given level of fire suppression they remained remarkably similar in terms of overall composition, structure, and landscape pattern, while the +6° scenarios separated noticeably from them. Such decisive differences suggest that under the simulated ranges of precipitation and fire suppression, the interval between 3 and 6 degrees of warming on this landscape may capture an ecological threshold, or tipping point. Additional simulation research that incorporates (for example) management actions, insects and pathogens, and a wider array of precipitation scenarios could help illuminate more clearly the possible range of future landscape conditions. Still, these results provide a glimpse of potential divergent outcomes on this important landscape under possible future climates, and suggest that these forests will undergo considerable changes from both historical and current conditions in response to higher temperatures expected in this area. Some changes may be inevitable with warming, such as the upslope shift of warm forest types, but careful planning for fire and fuels management might allow land managers to modulate fire behavior and steer vegetation dynamics toward the most desirable outcome possible. Title: Potential effects of climate change and fire management on fire behavior and vegetation patterns on an east Cascades landscape Author: Greaves, Heather E. Climate exerts considerable control on wildfire regimes, and climate and wildfire are both major drivers of forest growth and succession in interior Northwest forests. Estimating potential response of these landscapes to anticipated changes in climate helps researchers and land managers understand and mitigate impacts of climate change on important ecological and economic resources. Spatially explicit, mechanistic computer simulation models are powerful tools that permit researchers to incorporate climate and disturbance events along with vegetation physiology and phenology to explore complex potential effects of climate change over wide spatial and temporal scales. In this thesis, I used the simulation model FireBGCv2 to characterize potential response of fire, vegetation, and landscape dynamics to a range of possible future climate and fire management scenarios. The simulation landscape (~43,000 hectares) is part of Deschutes National Forest, which is located at the interface of maritime and continental climates and is known for its beauty and ecological diversity. Simulation scenarios included all combinations of +0°C, +3°C, and +6°C of warming; +10%, ±0%, and -10% historical precipitation; and 10% and 90% fire suppression, and were run for 500 years. To characterize fire dynamics, I investigated how mean fire frequency, intensity, and fuel loadings changed over time in all scenarios, and how fire and tree mortality interacted over time. To explore vegetation and landscape dynamics, I described the distribution and spatial arrangement of vegetation types and forest successional stages on the landscape, and used a nonmetric multidimensional scaling (NMS) ordination to holistically evaluate overall similarity of composition, structure, and landscape pattern among all simulation scenarios over time. Changes in precipitation had little effect on fire characteristics or vegetation and landscape characteristics, indicating that simulated precipitation changes were not sufficient to significantly affect vegetation moisture stress or fire behavior on this landscape. Current heavy fuel loads controlled early fire dynamics, with high mean fire intensities occurring early in all simulations. Increases in fire frequency accompanied all temperature increases, leading to decreasing fuel loads and fire intensities over time in warming scenarios. With no increase in temperature or in fire frequency, high fire intensities and heavier fuel loads were sustained. Over time, more fire associated with warming or less fire suppression increased the percentage of the landscape occupied by non-forest and fire-sensitive early seral forest successional stages, which tended to increase the percentage of fire area burning at high severity (in terms of tree mortality). This fire-vegetation relationship may reflect a return to a more historical range of conditions on this landscape. Higher temperatures and fire frequency led to significant spatial migration of forest types across the landscape, with communities at the highest and lowest elevations particularly affected. Warming led to an upslope shift of warm mixed conifer and ponderosa pine (Pinus ponderosa) forests, severely contracting (under 3° of warming) or eliminating (under 6° of warming) area dominated by mountain hemlock (Tsuga mertensiana) and cool, wet conifer forest in the high western portion of the landscape. In lower elevations, warming and fire together contributed to significant expansion of open (<10% tree canopy cover) forest and grass- and shrubland. The compositional changes and spatial shifts simulated in the warming scenarios suggest that climate change is likely to significantly affect forests on this landscape. Warming and associated fire also tended to increase heterogeneity of forest structural stages and landscape pattern, resulting in a more diverse distribution of structural stages, especially in lower elevations, and a more divided landscape of smaller forest stands. The NMS ordination emphasized the dissimilarity between the severe +6° scenarios and the other two temperature scenarios. The +0° and +3° scenarios differed from each other in composition (mainly because cool forest was lost in the +3° scenarios), but within a given level of fire suppression they remained remarkably similar in terms of overall composition, structure, and landscape pattern, while the +6° scenarios separated noticeably from them. Such decisive differences suggest that under the simulated ranges of precipitation and fire suppression, the interval between 3 and 6 degrees of warming on this landscape may capture an ecological threshold, or tipping point. Additional simulation research that incorporates (for example) management actions, insects and pathogens, and a wider array of precipitation scenarios could help illuminate more clearly the possible range of future landscape conditions. Still, these results provide a glimpse of potential divergent outcomes on this important landscape under possible future climates, and suggest that these forests will undergo considerable changes from both historical and current conditions in response to higher temperatures expected in this area. Some changes may be inevitable with warming, such as the upslope shift of warm forest types, but careful planning for fire and fuels management might allow land managers to modulate fire behavior and steer vegetation dynamics toward the most desirable outcome possible. Close

• 42. [Article] The role of herbivores and productivity on community structure of rocky shores of the Galapagos Islands, Ecuador

  Ecosystems are facing increasing threats from human related activities, such as overfishing, pollution, habitat destruction, species invasions, and diseases, among others. While oceanic islands provide ...

  Citation × Citation Citation Abstract Copy Title: The role of herbivores and productivity on community structure of rocky shores of the Galapagos Islands, Ecuador Author: Vinueza, Luis R. Ecosystems are facing increasing threats from human related activities, such as overfishing, pollution, habitat destruction, species invasions, and diseases, among others. While oceanic islands provide natural laboratories to understand ecological and evolutionary process, they are also particularly vulnerable to these impacts, given their usual isolation from the mainland and the typically high endemism of their flora and fauna. However, we still lack a general understanding of how marine systems in the Galapagos Islands will be affected by multiple human impacts, more severe environmental perturbations and warmer oceans. Rocky shores have been a prime example for the advancement of ecological theories and for the creation of important concepts to support management decisions and conservation actions, such as the predation hypothesis, the keystone species concept and the development of environmental stress models. However, the majority of this knowledge comes from studies conducted at higher latitudes. While most attention in the tropics has been focused on coral reefs and mangroves, other habitats such as rocky shores have remained largely unexplored. The upwelling ecosystems of the Galapagos Archipelago constitute an ideal model where likely consequences of interactions between global climate change and human impacts (e.g. exploitation) can be studied. In particular, variation in ocean upwelling and downwelling conditions (Palacios 2004) associated with seasonal and interannual variability and large scale oceanic-atmospheric perturbations such as ENSO cycles with its warm El Niño (~cessation of upwelling conditions) and cold La Niña (~abnormal upwelling) phase (Chavez et al. 1999). Thus, the Galapagos situation offers a scenario whereby I can assess the interaction among nutrient supply, herbivory and abiotic fluctuations. I used this dynamic system to evaluate the influence of bottom up and top down effects on rocky shore communities. In Chapter 2 I evaluated the role of consumers at different levels of productivity. I manipulated four levels of herbivory, from no macro-herbivores to all herbivores present, combinations of all together, mostly fish, crabs, crabs and including marine iguanas, crabs, sea turtles and fish. I demonstrated that at sites of low productivity herbivores had consistent effects on community structure by reducing the abundance of erect macroalgae which decreased macroalgal and sessile invertebrate's species richness, diversity and evenness. In areas of mid and high productivity the role of consumers was affected by seasonal effects and by warm and cold phases of El Niño Southern Oscillation. In Chapter 3 I evaluated the interactive effect of consumers on species richness, diversity and evenness of primary producers and discussed the results in the context of prevailing top down views on the regulation of marine tropical communities. I further discuss the importance to manage both top down and bottom up factors to maintain ecosystem structure and function at tropical locations. In chapter 4 I used resource and consumer-stress models to predict the outcome of plant animal interactions. I observed how the impact of herbivory on primary producers was exacerbated by thermal stress and reduced algal biomass at times of low productivity and high temperature; this pattern shifted as productivity increased and thermal stress relaxed, which led to herbivores increasing, not decreasing algal biomass. Finally, chapter 5 provides the main conclusions about our work. I put our work in context of past and present ecological theories. I also offer a framework to manage this system, oriented to increasing the resistance and resilience of this fragile ecosystem. Title: The role of herbivores and productivity on community structure of rocky shores of the Galapagos Islands, Ecuador Author: Vinueza, Luis R. Ecosystems are facing increasing threats from human related activities, such as overfishing, pollution, habitat destruction, species invasions, and diseases, among others. While oceanic islands provide natural laboratories to understand ecological and evolutionary process, they are also particularly vulnerable to these impacts, given their usual isolation from the mainland and the typically high endemism of their flora and fauna. However, we still lack a general understanding of how marine systems in the Galapagos Islands will be affected by multiple human impacts, more severe environmental perturbations and warmer oceans. Rocky shores have been a prime example for the advancement of ecological theories and for the creation of important concepts to support management decisions and conservation actions, such as the predation hypothesis, the keystone species concept and the development of environmental stress models. However, the majority of this knowledge comes from studies conducted at higher latitudes. While most attention in the tropics has been focused on coral reefs and mangroves, other habitats such as rocky shores have remained largely unexplored. The upwelling ecosystems of the Galapagos Archipelago constitute an ideal model where likely consequences of interactions between global climate change and human impacts (e.g. exploitation) can be studied. In particular, variation in ocean upwelling and downwelling conditions (Palacios 2004) associated with seasonal and interannual variability and large scale oceanic-atmospheric perturbations such as ENSO cycles with its warm El Niño (~cessation of upwelling conditions) and cold La Niña (~abnormal upwelling) phase (Chavez et al. 1999). Thus, the Galapagos situation offers a scenario whereby I can assess the interaction among nutrient supply, herbivory and abiotic fluctuations. I used this dynamic system to evaluate the influence of bottom up and top down effects on rocky shore communities. In Chapter 2 I evaluated the role of consumers at different levels of productivity. I manipulated four levels of herbivory, from no macro-herbivores to all herbivores present, combinations of all together, mostly fish, crabs, crabs and including marine iguanas, crabs, sea turtles and fish. I demonstrated that at sites of low productivity herbivores had consistent effects on community structure by reducing the abundance of erect macroalgae which decreased macroalgal and sessile invertebrate's species richness, diversity and evenness. In areas of mid and high productivity the role of consumers was affected by seasonal effects and by warm and cold phases of El Niño Southern Oscillation. In Chapter 3 I evaluated the interactive effect of consumers on species richness, diversity and evenness of primary producers and discussed the results in the context of prevailing top down views on the regulation of marine tropical communities. I further discuss the importance to manage both top down and bottom up factors to maintain ecosystem structure and function at tropical locations. In chapter 4 I used resource and consumer-stress models to predict the outcome of plant animal interactions. I observed how the impact of herbivory on primary producers was exacerbated by thermal stress and reduced algal biomass at times of low productivity and high temperature; this pattern shifted as productivity increased and thermal stress relaxed, which led to herbivores increasing, not decreasing algal biomass. Finally, chapter 5 provides the main conclusions about our work. I put our work in context of past and present ecological theories. I also offer a framework to manage this system, oriented to increasing the resistance and resilience of this fragile ecosystem. Close

• 43. [Article] The Performance of Four Native Perennial Forb Species Along a Climate Gradient in Pacific Northwest Prairies

  To determine how Pacific Northwest prairies are influenced by local site factors versus. regional climate, we studied the reproduction, plant size, and density of sixteen natural populations of four perennial ...

  Citation × Citation Citation Abstract Copy Title: The Performance of Four Native Perennial Forb Species Along a Climate Gradient in Pacific Northwest Prairies Author: Hendricks, Lauren Year: 2016 To determine how Pacific Northwest prairies are influenced by local site factors versus. regional climate, we studied the reproduction, plant size, and density of sixteen natural populations of four perennial forb species native to Pacific Northwest prairies: Ranunculus austro-oreganus, Sidalcea malviflora spp. virgata, Microseris laciniata, and Eriophyllum lanatum. These populations were distributed along a 700 kilometer latitudinal gradient from southern Oregon to Whidbey Island, Washington. We found significant differences in plant size and reproduction among populations for all species, but correlations among edaphic and climate variables and plant size and reproduction were weak. Instead, density was more strongly correlated with both edaphic and climate variables, suggesting that this is a better indicator of long-term demographic processes. Although a few factors are important across species (e.g., nutrient availability and minimum temperature), response is idiosyncratic at the individual species level in Pacific Northwest prairies. Title: The Performance of Four Native Perennial Forb Species Along a Climate Gradient in Pacific Northwest Prairies Author: Hendricks, Lauren Year: 2016 To determine how Pacific Northwest prairies are influenced by local site factors versus. regional climate, we studied the reproduction, plant size, and density of sixteen natural populations of four perennial forb species native to Pacific Northwest prairies: Ranunculus austro-oreganus, Sidalcea malviflora spp. virgata, Microseris laciniata, and Eriophyllum lanatum. These populations were distributed along a 700 kilometer latitudinal gradient from southern Oregon to Whidbey Island, Washington. We found significant differences in plant size and reproduction among populations for all species, but correlations among edaphic and climate variables and plant size and reproduction were weak. Instead, density was more strongly correlated with both edaphic and climate variables, suggesting that this is a better indicator of long-term demographic processes. Although a few factors are important across species (e.g., nutrient availability and minimum temperature), response is idiosyncratic at the individual species level in Pacific Northwest prairies. Close

• 44. [Article] Climate change impacts on mountain snowpack presented in a knowledge to action framework

  Throughout many of the world’s mountain ranges snowpack accumulates during the winter and into the spring, providing a natural reservoir for water. As this reservoir melts, it fills streams and recharges ...

  Citation × Citation Citation Abstract Copy Title: Climate change impacts on mountain snowpack presented in a knowledge to action framework Author: Sproles, Eric Allan Throughout many of the world’s mountain ranges snowpack accumulates during the winter and into the spring, providing a natural reservoir for water. As this reservoir melts, it fills streams and recharges groundwater for over 1 billion people globally. Despite its importance to water resources, our understanding of the storage capacity of mountain snowpack is incomplete. This partial knowledge limits our abilities to assess the impact that projected climate conditions will have on mountain snowpack and water resources. While understanding the effect of projected climate on mountain snowpack is a global question, it can be best understood at the basin scale. It is at this level that decision makers and water resource managers base their decisions and require a clarified understanding of basin's mountain snowpack. The McKenzie River Basin located in the central-western Cascades of Oregon exhibits characteristics typical of many mountain river systems globally and in the Pacific Northwestern United States. Here snowmelt provides critical water supply for hydropower, agriculture, ecosystems, recreation, and municipalities. While there is a surplus of water in winter, the summer months see flows reach a minimum and the same groups have to compete for a limited supply. Throughout the Pacific Northwestern United States, current analyses and those of projected future climate change impacts show rising temperatures, diminished snowpacks, and declining summertime streamflow. The impacts of climate change on water resources presents new challenges and requires fresh approaches to understanding problems that are only beginning to be recognized. Climate change also presents challenges to decision makers who need new kinds of climate and water information, and will need the scientific research community to help provide improved means of knowledge transfer. This dissertation quantified the basin-wide distribution of snowpack across multiple decades in present and in projected climate conditions, describing a 56% decrease in mountain snowpack with regional projected temperature increases. These results were used to develop a probabilistic understanding of snowpack in projected climates. This section described a significant shift in statistical relations of snowpack. One that would be statistically likely to accumulate every 3 out of 4 years would accumulate in 1 out of 20 years. Finally this research identifies methods to improved knowledge transfer from the research community to water resource professionals. Implementation of these recommendations would enable a more effective means of dissemination to stakeholders and policy makers. While this research focused only on the McKenzie River Basin, it has regional applications. Processes affecting snowpack in the McKenzie River Basin are similar to those in many other maritime, forested Pacific Northwest watersheds. The framework of this research could also be applied to regions outside of the Pacific Northwestern United States to gain a similar level of understanding of climate impacts on mountain snowpack. Title: Climate change impacts on mountain snowpack presented in a knowledge to action framework Author: Sproles, Eric Allan Throughout many of the world’s mountain ranges snowpack accumulates during the winter and into the spring, providing a natural reservoir for water. As this reservoir melts, it fills streams and recharges groundwater for over 1 billion people globally. Despite its importance to water resources, our understanding of the storage capacity of mountain snowpack is incomplete. This partial knowledge limits our abilities to assess the impact that projected climate conditions will have on mountain snowpack and water resources. While understanding the effect of projected climate on mountain snowpack is a global question, it can be best understood at the basin scale. It is at this level that decision makers and water resource managers base their decisions and require a clarified understanding of basin's mountain snowpack. The McKenzie River Basin located in the central-western Cascades of Oregon exhibits characteristics typical of many mountain river systems globally and in the Pacific Northwestern United States. Here snowmelt provides critical water supply for hydropower, agriculture, ecosystems, recreation, and municipalities. While there is a surplus of water in winter, the summer months see flows reach a minimum and the same groups have to compete for a limited supply. Throughout the Pacific Northwestern United States, current analyses and those of projected future climate change impacts show rising temperatures, diminished snowpacks, and declining summertime streamflow. The impacts of climate change on water resources presents new challenges and requires fresh approaches to understanding problems that are only beginning to be recognized. Climate change also presents challenges to decision makers who need new kinds of climate and water information, and will need the scientific research community to help provide improved means of knowledge transfer. This dissertation quantified the basin-wide distribution of snowpack across multiple decades in present and in projected climate conditions, describing a 56% decrease in mountain snowpack with regional projected temperature increases. These results were used to develop a probabilistic understanding of snowpack in projected climates. This section described a significant shift in statistical relations of snowpack. One that would be statistically likely to accumulate every 3 out of 4 years would accumulate in 1 out of 20 years. Finally this research identifies methods to improved knowledge transfer from the research community to water resource professionals. Implementation of these recommendations would enable a more effective means of dissemination to stakeholders and policy makers. While this research focused only on the McKenzie River Basin, it has regional applications. Processes affecting snowpack in the McKenzie River Basin are similar to those in many other maritime, forested Pacific Northwest watersheds. The framework of this research could also be applied to regions outside of the Pacific Northwestern United States to gain a similar level of understanding of climate impacts on mountain snowpack. Close

• 45. [Article] Predicting landscape sensitivity to present and future floods in the Pacific Northwest, USA

  Supporting information is available online at: http://onlinelibrary.wiley.com/doi/10.1002/hyp.10553/suppinfo

  Citation × Citation Citation Abstract Copy Title: Predicting landscape sensitivity to present and future floods in the Pacific Northwest, USA Author: Lewis, Sarah L., Safeeq, Mohammad, Staab, Brian, Grant, Gordon E. Supporting information is available online at: http://onlinelibrary.wiley.com/doi/10.1002/hyp.10553/suppinfo Title: Predicting landscape sensitivity to present and future floods in the Pacific Northwest, USA Author: Lewis, Sarah L., Safeeq, Mohammad, Staab, Brian, Grant, Gordon E. Supporting information is available online at: http://onlinelibrary.wiley.com/doi/10.1002/hyp.10553/suppinfo Close

• 46. [Article] Climate Change: Natural Variability is a Big Deal Too!

  This is a presentation from The Oregon Water Conference 2011: Evaluating and Managing Water Resources in a Climate of Uncertainty Oregon State University – CH2M Hill Alumni Center – Corvallis, Oregon. OR ...

  Citation × Citation Citation Abstract Copy Title: Climate Change: Natural Variability is a Big Deal Too! Author: Curtis, David C., Prakash, Om Year: 2011 This is a presentation from The Oregon Water Conference 2011: Evaluating and Managing Water Resources in a Climate of Uncertainty Oregon State University – CH2M Hill Alumni Center – Corvallis, Oregon. OR Section, American Water Resources Association and OR Section, American Institute of Hydrology Title: Climate Change: Natural Variability is a Big Deal Too! Author: Curtis, David C., Prakash, Om Year: 2011 This is a presentation from The Oregon Water Conference 2011: Evaluating and Managing Water Resources in a Climate of Uncertainty Oregon State University – CH2M Hill Alumni Center – Corvallis, Oregon. OR Section, American Water Resources Association and OR Section, American Institute of Hydrology Close

• 47. [Article] Outcome Distributions in Impact Assessment : Climate Change and Technology Adoption in Pacific Northwest Agriculture

  Increased temperature and precipitation variability and frequent extreme weather events due to climate change pose a threat to farming operations and agricultural communities. The recent IPCC assessment ...

  Citation × Citation Citation Abstract Copy Title: Outcome Distributions in Impact Assessment : Climate Change and Technology Adoption in Pacific Northwest Agriculture Author: Zhang, Hongliang Increased temperature and precipitation variability and frequent extreme weather events due to climate change pose a threat to farming operations and agricultural communities. The recent IPCC assessment shows that the projected climate change will, on average, reduce wheat yields by 5% in temperate regions without adaptation and even more if temperatures continue to rise. Designing policies for helping climate-vulnerable farmers requires a comprehensive understanding of the impacts of climate change on agricultural systems and potential adaptation strategies. This dissertation consists of three essays that address several relevant issues from an economic perspective. The first essay presents an empirical analysis to assess the impacts of climate change on farm-level economic outcome distributions for winter wheat systems (including winter wheat yield, farm revenue, expenditure, and net return) in the U.S. Pacific Northwest by using a flexible moment-based approach. Results indicate that a warming climate, on average, reduces winter wheat yield but increases farm economic returns in this region, while droughts have a large negative impact on the ex-ante distributions of winter wheat yields and farm net returns. Using the econometric estimates, the farm-level climate vulnerability is quantified and examined. The second essay examines the effects of conservation tillage (including no-till and other conservation tillage) on winter wheat yield and production risk. We test the hypothesis that conservation tillage practices are risk-reducing. We use farm-level tillage practice data from the 2012 Agricultural Census for the U.S. Pacific Northwest. Results are estimated using a three-stage approach by integrating a multinomial logit model with a flexible moment-based approach. We find that conservation tillage has a negative effect on winter wheat productivity. We also find statistical evidence that conservation tillage is risk-increasing. Implications of the results for using conservation tillage to adapt to climate change are discussed. The third essay compares the difference-in-difference and fixed effects approaches to estimate long-term climate impacts versus short-term weather effects on U.S winter wheat systems. A county-level panel dataset is used to assess the effects of climate and weather variables on winter wheat yield and farm revenue in the U.S. Pacific Northwest and the central Great Plains. The net effect of a warming climate is found to be negative on the winter wheat production both in the short run and the long run. Implications of the results for short-term adjustments and long-term adaptations are discussed. Title: Outcome Distributions in Impact Assessment : Climate Change and Technology Adoption in Pacific Northwest Agriculture Author: Zhang, Hongliang Increased temperature and precipitation variability and frequent extreme weather events due to climate change pose a threat to farming operations and agricultural communities. The recent IPCC assessment shows that the projected climate change will, on average, reduce wheat yields by 5% in temperate regions without adaptation and even more if temperatures continue to rise. Designing policies for helping climate-vulnerable farmers requires a comprehensive understanding of the impacts of climate change on agricultural systems and potential adaptation strategies. This dissertation consists of three essays that address several relevant issues from an economic perspective. The first essay presents an empirical analysis to assess the impacts of climate change on farm-level economic outcome distributions for winter wheat systems (including winter wheat yield, farm revenue, expenditure, and net return) in the U.S. Pacific Northwest by using a flexible moment-based approach. Results indicate that a warming climate, on average, reduces winter wheat yield but increases farm economic returns in this region, while droughts have a large negative impact on the ex-ante distributions of winter wheat yields and farm net returns. Using the econometric estimates, the farm-level climate vulnerability is quantified and examined. The second essay examines the effects of conservation tillage (including no-till and other conservation tillage) on winter wheat yield and production risk. We test the hypothesis that conservation tillage practices are risk-reducing. We use farm-level tillage practice data from the 2012 Agricultural Census for the U.S. Pacific Northwest. Results are estimated using a three-stage approach by integrating a multinomial logit model with a flexible moment-based approach. We find that conservation tillage has a negative effect on winter wheat productivity. We also find statistical evidence that conservation tillage is risk-increasing. Implications of the results for using conservation tillage to adapt to climate change are discussed. The third essay compares the difference-in-difference and fixed effects approaches to estimate long-term climate impacts versus short-term weather effects on U.S winter wheat systems. A county-level panel dataset is used to assess the effects of climate and weather variables on winter wheat yield and farm revenue in the U.S. Pacific Northwest and the central Great Plains. The net effect of a warming climate is found to be negative on the winter wheat production both in the short run and the long run. Implications of the results for short-term adjustments and long-term adaptations are discussed. Close

• 48. [Article] Characterizing Linkages Between the Climate, Cryosphere, and Impacts on Run-of-River Hydropower in Data-Sparse Mountain Environments

  In many regions of the world, a significant portion of the surface water originates in mountain headwaters where the timing and magnitude of streamflow is largely dictated by the seasonal storage of precipitation ...

  Citation × Citation Citation Abstract Copy Title: Characterizing Linkages Between the Climate, Cryosphere, and Impacts on Run-of-River Hydropower in Data-Sparse Mountain Environments Author: Mosier, Thomas M. In many regions of the world, a significant portion of the surface water originates in mountain headwaters where the timing and magnitude of streamflow is largely dictated by the seasonal storage of precipitation as snowpack and long-term storage as glaciers. Accumulation, persistence, and melt of snow and ice are functions of the climate in which they exist and therefore respond to changes in that climate. One important use of water in many regions is for hydropower energy production. While reservoir-based hydropower infrastructure has some ability to absorb changes in timing of streamflow, run-of-river hydropower infrastructure does not. Thus, in assessing the economic feasibility of new or existing run-of-river infrastructure, it is important to account for potential impacts climate change may have over the lifetime of the project. Projecting impacts of climate change on surface water resources, and in particular on run-of-river hydropower resource potential, requires robustly characterizing the linkages between the climate, cryosphere, and streamflow. Two obstacles to increasing our understanding of mountain systems are the sparsity of observation data and complexity of weather patterns. The first part of my research addresses the issue of climate data availability in mountain regions through development of statistical models to characterize the high-spatial resolution distribution of historic and projected future precipitation and temperature. I demonstrate these climate products through projecting long-term changes in snowfall for the Alaska Range, Alps, Central Andes, and Himalaya-Karakoram-Hindu Kush ranges. I then present a framework for assessing conceptual cryosphere hydrology models and implement the framework for two long-term glacier study sites in Alaska, USA. Using this framework, I identify novel formulations for modeling the heat transfer and energy balance of snowpacks and glaciers that improve model robustness relative to the current generation of cryosphere hydrology models typically used in data-sparse mountain environments. I then demonstrate a method for understanding the impacts of projected future climate change on run-of-river hydropower resource potential, using Falls Creek in Oregon, USA as a test case. A core value of this work is producing models that can be straightforwardly applied to any region, thus decreasing the impacts of data disparities between regions on our ability to characterize climate change impacts on mountain regions. Title: Characterizing Linkages Between the Climate, Cryosphere, and Impacts on Run-of-River Hydropower in Data-Sparse Mountain Environments Author: Mosier, Thomas M. In many regions of the world, a significant portion of the surface water originates in mountain headwaters where the timing and magnitude of streamflow is largely dictated by the seasonal storage of precipitation as snowpack and long-term storage as glaciers. Accumulation, persistence, and melt of snow and ice are functions of the climate in which they exist and therefore respond to changes in that climate. One important use of water in many regions is for hydropower energy production. While reservoir-based hydropower infrastructure has some ability to absorb changes in timing of streamflow, run-of-river hydropower infrastructure does not. Thus, in assessing the economic feasibility of new or existing run-of-river infrastructure, it is important to account for potential impacts climate change may have over the lifetime of the project. Projecting impacts of climate change on surface water resources, and in particular on run-of-river hydropower resource potential, requires robustly characterizing the linkages between the climate, cryosphere, and streamflow. Two obstacles to increasing our understanding of mountain systems are the sparsity of observation data and complexity of weather patterns. The first part of my research addresses the issue of climate data availability in mountain regions through development of statistical models to characterize the high-spatial resolution distribution of historic and projected future precipitation and temperature. I demonstrate these climate products through projecting long-term changes in snowfall for the Alaska Range, Alps, Central Andes, and Himalaya-Karakoram-Hindu Kush ranges. I then present a framework for assessing conceptual cryosphere hydrology models and implement the framework for two long-term glacier study sites in Alaska, USA. Using this framework, I identify novel formulations for modeling the heat transfer and energy balance of snowpacks and glaciers that improve model robustness relative to the current generation of cryosphere hydrology models typically used in data-sparse mountain environments. I then demonstrate a method for understanding the impacts of projected future climate change on run-of-river hydropower resource potential, using Falls Creek in Oregon, USA as a test case. A core value of this work is producing models that can be straightforwardly applied to any region, thus decreasing the impacts of data disparities between regions on our ability to characterize climate change impacts on mountain regions. Close

• 49. [Article] Regional Scale Modeling of Climate, Cryosphere, and Freshwater Discharge in Changing Coastal Mountain Environments

  The glaciated coastal mountain watersheds that drain into the Gulf of Alaska (GOA) provide a model laboratory to explore the challenges of hydrological modeling and study the impact of climate and glacier ...

  Citation × Citation Citation Abstract Copy Title: Regional Scale Modeling of Climate, Cryosphere, and Freshwater Discharge in Changing Coastal Mountain Environments Author: Beamer, Jordan P. The glaciated coastal mountain watersheds that drain into the Gulf of Alaska (GOA) provide a model laboratory to explore the challenges of hydrological modeling and study the impact of climate and glacier cover change on regional hydrology. The region is data-sparse and contains a complex assemblage of topography and land cover, including a system of mountain glaciers that are retreating at some of the highest rates on Earth. The high rates of runoff from precipitation and glacial melt delivered by coastal rivers influence ocean circulation patterns, rates of global sea level rise, and provide spawning habitat for the large salmon populations. Physically-based hydrological modeling of the major water budget components of the GOA, driven using historical reanalysis weather data and land cover, reveals that the modeled water budget components, particularly precipitation input, vary widely between commonly-used weather products. The majority of the large freshwater flux into the GOA is derived from distributed coastal streams rather than the large inland rivers. The modeled seasonal aggregated GOA hydrograph is dominated by the spring and early summer snowmelt, and supplemented by late summer glacial ice melt. Model results demonstrate good agreement with NASA Gravity Recovery and Climate Experiment (GRACE) satellite data in terms of annual amplitudes and long term losses (ice loss), and suggest that existing GRACE solutions, previously reported to represent glacier mass balance alone, are actually measuring the full water budget of land and ice surfaces. An ensemble of climate models and future emissions scenarios were paired with systematically altered land cover to test the sensitivity of the hydrologic system to changes in regional climate patterns and glacier coverage representative of late twenty first century conditions. Compared with the hindcast simulations, the model results forced with increased regional air temperatures and precipitation inputs and reduced glacier cover produce an increase in the annual GOA freshwater discharge volume. The seasonal GOA hydrograph is flattened due to increased winter runoff from more winter rainfall and less snow accumulation, and lower levels of snowmelt and glacier ice contribution. Large uncertainties exist in the direction of change in the glacier runoff component, primarily due to uncertainties that exist in predicting glacier response to climate change. Hydrological modeling with high resolution and inclusion of relevant physical processes can produce significantly improved products that are of high value to and in demand by numerous other scientific communities. However, the value and accuracy of the output from the hydrologic model is highly dependent on the weather forcing quality. Given the considerable importance of quality weather forcing for hydrologic modeling, it is imperative to assess the suitability of multiple products by evaluating local and regional performance and accounting for uncertainty. Additional efforts should be made to improve the spatial resolution of the reanalysis through downscaling and to strategically increase the number of weather stations at high elevations and incorporate that data into weather forcing datasets. Title: Regional Scale Modeling of Climate, Cryosphere, and Freshwater Discharge in Changing Coastal Mountain Environments Author: Beamer, Jordan P. The glaciated coastal mountain watersheds that drain into the Gulf of Alaska (GOA) provide a model laboratory to explore the challenges of hydrological modeling and study the impact of climate and glacier cover change on regional hydrology. The region is data-sparse and contains a complex assemblage of topography and land cover, including a system of mountain glaciers that are retreating at some of the highest rates on Earth. The high rates of runoff from precipitation and glacial melt delivered by coastal rivers influence ocean circulation patterns, rates of global sea level rise, and provide spawning habitat for the large salmon populations. Physically-based hydrological modeling of the major water budget components of the GOA, driven using historical reanalysis weather data and land cover, reveals that the modeled water budget components, particularly precipitation input, vary widely between commonly-used weather products. The majority of the large freshwater flux into the GOA is derived from distributed coastal streams rather than the large inland rivers. The modeled seasonal aggregated GOA hydrograph is dominated by the spring and early summer snowmelt, and supplemented by late summer glacial ice melt. Model results demonstrate good agreement with NASA Gravity Recovery and Climate Experiment (GRACE) satellite data in terms of annual amplitudes and long term losses (ice loss), and suggest that existing GRACE solutions, previously reported to represent glacier mass balance alone, are actually measuring the full water budget of land and ice surfaces. An ensemble of climate models and future emissions scenarios were paired with systematically altered land cover to test the sensitivity of the hydrologic system to changes in regional climate patterns and glacier coverage representative of late twenty first century conditions. Compared with the hindcast simulations, the model results forced with increased regional air temperatures and precipitation inputs and reduced glacier cover produce an increase in the annual GOA freshwater discharge volume. The seasonal GOA hydrograph is flattened due to increased winter runoff from more winter rainfall and less snow accumulation, and lower levels of snowmelt and glacier ice contribution. Large uncertainties exist in the direction of change in the glacier runoff component, primarily due to uncertainties that exist in predicting glacier response to climate change. Hydrological modeling with high resolution and inclusion of relevant physical processes can produce significantly improved products that are of high value to and in demand by numerous other scientific communities. However, the value and accuracy of the output from the hydrologic model is highly dependent on the weather forcing quality. Given the considerable importance of quality weather forcing for hydrologic modeling, it is imperative to assess the suitability of multiple products by evaluating local and regional performance and accounting for uncertainty. Additional efforts should be made to improve the spatial resolution of the reanalysis through downscaling and to strategically increase the number of weather stations at high elevations and incorporate that data into weather forcing datasets. Close

• 50. [Article] Climate shifts the interaction web of a marine plankton community

  This is the publisher’s final pdf. The published article is copyrighted by John Wiley & Sons, Inc. and can be found at: http://onlinelibrary.wiley.com/journal/10.1111/%28ISSN%291365-2486. This article ...

  Citation × Citation Citation Abstract Copy Title: Climate shifts the interaction web of a marine plankton community Author: Tolimieri, Nick, Francis, Tessa B., Peterson, William T., Scheuerell, Mark D., Ruzicka, James J., Brodeur, Richard D., Levin, Phillip S. This is the publisher’s final pdf. The published article is copyrighted by John Wiley & Sons, Inc. and can be found at: http://onlinelibrary.wiley.com/journal/10.1111/%28ISSN%291365-2486. This article is a U.S. Government work and is in the public domain in the U.S.A. Title: Climate shifts the interaction web of a marine plankton community Author: Tolimieri, Nick, Francis, Tessa B., Peterson, William T., Scheuerell, Mark D., Ruzicka, James J., Brodeur, Richard D., Levin, Phillip S. This is the publisher’s final pdf. The published article is copyrighted by John Wiley & Sons, Inc. and can be found at: http://onlinelibrary.wiley.com/journal/10.1111/%28ISSN%291365-2486. This article is a U.S. Government work and is in the public domain in the U.S.A. Close

• 51. [Article] Climate effects on red alder growth in the Pacific Northwest of North America

  This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/forest-ecology-...

  Citation × Citation Citation Abstract Copy Title: Climate effects on red alder growth in the Pacific Northwest of North America Author: Hibbs, D. E., Cortini, F., Bluhm, A., Wang, T., Comeau, P. G. This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/forest-ecology-and-management/. Title: Climate effects on red alder growth in the Pacific Northwest of North America Author: Hibbs, D. E., Cortini, F., Bluhm, A., Wang, T., Comeau, P. G. This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/forest-ecology-and-management/. Close

• 52. [Article] Climate Change and Shifts in Water Related Ecosystem Services in the Tualatin and Yamhill River Basins

  Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR.

  Citation × Citation Citation Abstract Copy Title: Climate Change and Shifts in Water Related Ecosystem Services in the Tualatin and Yamhill River Basins Author: Chang, Heejun, Sharma, Manu, Ennaanay, Driss, Anthony, Terrance Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Title: Climate Change and Shifts in Water Related Ecosystem Services in the Tualatin and Yamhill River Basins Author: Chang, Heejun, Sharma, Manu, Ennaanay, Driss, Anthony, Terrance Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Close

• 53. [Article] Climate Change Impact on Drought Risk and Uncertainty in the Willamette River Basin

  Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR.

  Citation × Citation Citation Abstract Copy Title: Climate Change Impact on Drought Risk and Uncertainty in the Willamette River Basin Author: Chang, Heejun, Jung, Il-Won Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Title: Climate Change Impact on Drought Risk and Uncertainty in the Willamette River Basin Author: Chang, Heejun, Jung, Il-Won Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Close

• 54. [Article] Dynamics of a recovering Arctic bird population: the importance of climate, density dependence, and site quality

  The Appendix is available online: http://dx.doi.org/10.1890/14-1591.1.sm

  Citation × Citation Citation Abstract Copy Title: Dynamics of a recovering Arctic bird population: the importance of climate, density dependence, and site quality Author: Bruggeman, Jason E., Nigro, Debora, Swem, Ted, Kennedy, Patricia L., Andersen, David E. The Appendix is available online: http://dx.doi.org/10.1890/14-1591.1.sm Title: Dynamics of a recovering Arctic bird population: the importance of climate, density dependence, and site quality Author: Bruggeman, Jason E., Nigro, Debora, Swem, Ted, Kennedy, Patricia L., Andersen, David E. The Appendix is available online: http://dx.doi.org/10.1890/14-1591.1.sm Close

• 55. [Article] Variability in mesoscale circulation and its effects on zooplankton distribution in the Northern California Current

  In eastern boundary current upwelling ecosystems, mesoscale circulation features such as eddies and upwelling filaments play a prominent role in the transfer of water and the associated plankton from the ...

  Citation × Citation Citation Abstract Copy Title: Variability in mesoscale circulation and its effects on zooplankton distribution in the Northern California Current Author: Keister, Julie Eileen In eastern boundary current upwelling ecosystems, mesoscale circulation features such as eddies and upwelling filaments play a prominent role in the transfer of water and the associated plankton from the productive nearshore to the oligotrophic deep sea. The relationship between mesoscale circulation, zooplankton distributions, and the across-shelf transport of coastal taxa and biomass in the California Current System was studied using data collected as part of the U.S. Global Ocean Ecosystems Dynamics (GLOBEC) Northeast Pacific Program. Sea surface height from >13 years of satellite altimeter data was used to characterize the spatial and temporal variability in mesoscale circulation in the northern California Current (35°N-49°N) and explore mechanisms of variability. High spatial and temporal variation in mesoscale energy occurred. Energy was not strongly linked to upwelling winds, but did correspond to climate indices, indicating that basin-scale processes play a role in controlling the circulation. CTD casts, zooplankton net tows, and Acoustic Doppler Current Profiler (ADCP) velocities collected during a research cruise conducted in summer 2000 off Oregon and northern California were used to describe the effects of mesoscale circulation on distributions of zooplankton. During the cruise, a filament of the coastal upwelling jet extended seaward of Cape Blanco (42.8°N) resulting in the displacement of coastal zooplankton to >100 km off the continental shelf. Velocities and standing stocks of zooplankton were used to estimate seaward transport of 0.5 Sv in the upper 100 m of the filament, in which zooplankton biomass averaged ~20 mg carbon/m³. That offshore transport equated to >900 metric tons of carbon each day, and 4-5x10⁴ tons over the 6-8 week lifetime of the circulation feature. Although the flux represented a small portion (<2%) of the shelf zooplankton biomass, the transport resulted in an offshore "hot-spot" in which biomass was 3-4X higher than in the surrounding ocean. Distributions of early life history stages of euphausiids indicated that retention of coastal populations may be strongly affected by the offshore advection. Finally, satellite sea surface temperature (SST) and sampling conducted during five summers were used to explore variability in the relationship between mesoscale circulation features and distributions of zooplankton. Circulation patterns differed among cruises and were reflected in zooplankton distributions. Circulation features resulted in the occurrence of cold surface water and coastal taxa offshore, but species abundances and presence/absence of taxa at specific locations were not predictable from satellite SSTs. These results are relevant to studies of ecosystem dynamics and the global carbon cycle because mesoscale circulation plays an important role in the seaward transport of carbon, retention and loss of taxa from the continental shelf, and creation of offshore structure which may be exploited by upper trophic level organisms. Title: Variability in mesoscale circulation and its effects on zooplankton distribution in the Northern California Current Author: Keister, Julie Eileen In eastern boundary current upwelling ecosystems, mesoscale circulation features such as eddies and upwelling filaments play a prominent role in the transfer of water and the associated plankton from the productive nearshore to the oligotrophic deep sea. The relationship between mesoscale circulation, zooplankton distributions, and the across-shelf transport of coastal taxa and biomass in the California Current System was studied using data collected as part of the U.S. Global Ocean Ecosystems Dynamics (GLOBEC) Northeast Pacific Program. Sea surface height from >13 years of satellite altimeter data was used to characterize the spatial and temporal variability in mesoscale circulation in the northern California Current (35°N-49°N) and explore mechanisms of variability. High spatial and temporal variation in mesoscale energy occurred. Energy was not strongly linked to upwelling winds, but did correspond to climate indices, indicating that basin-scale processes play a role in controlling the circulation. CTD casts, zooplankton net tows, and Acoustic Doppler Current Profiler (ADCP) velocities collected during a research cruise conducted in summer 2000 off Oregon and northern California were used to describe the effects of mesoscale circulation on distributions of zooplankton. During the cruise, a filament of the coastal upwelling jet extended seaward of Cape Blanco (42.8°N) resulting in the displacement of coastal zooplankton to >100 km off the continental shelf. Velocities and standing stocks of zooplankton were used to estimate seaward transport of 0.5 Sv in the upper 100 m of the filament, in which zooplankton biomass averaged ~20 mg carbon/m³. That offshore transport equated to >900 metric tons of carbon each day, and 4-5x10⁴ tons over the 6-8 week lifetime of the circulation feature. Although the flux represented a small portion (<2%) of the shelf zooplankton biomass, the transport resulted in an offshore "hot-spot" in which biomass was 3-4X higher than in the surrounding ocean. Distributions of early life history stages of euphausiids indicated that retention of coastal populations may be strongly affected by the offshore advection. Finally, satellite sea surface temperature (SST) and sampling conducted during five summers were used to explore variability in the relationship between mesoscale circulation features and distributions of zooplankton. Circulation patterns differed among cruises and were reflected in zooplankton distributions. Circulation features resulted in the occurrence of cold surface water and coastal taxa offshore, but species abundances and presence/absence of taxa at specific locations were not predictable from satellite SSTs. These results are relevant to studies of ecosystem dynamics and the global carbon cycle because mesoscale circulation plays an important role in the seaward transport of carbon, retention and loss of taxa from the continental shelf, and creation of offshore structure which may be exploited by upper trophic level organisms. Close

• 56. [Article] Dynamics of a recovering Arctic bird population: the importance of climate, density dependence, and site quality

  Appendix A is available online: http://dx.doi.org/10.1890/14-1591.1.sm

  Citation × Citation Citation Abstract Copy Title: Dynamics of a recovering Arctic bird population: the importance of climate, density dependence, and site quality Author: Bruggeman, Jason E., Nigro, Debora, Andersen, David E., Kennedy, Patricia L., Swem, Ted Appendix A is available online: http://dx.doi.org/10.1890/14-1591.1.sm Title: Dynamics of a recovering Arctic bird population: the importance of climate, density dependence, and site quality Author: Bruggeman, Jason E., Nigro, Debora, Andersen, David E., Kennedy, Patricia L., Swem, Ted Appendix A is available online: http://dx.doi.org/10.1890/14-1591.1.sm Close

• 57. [Article] Examining ectomycorrhizal communities of ponderosa pine and lodgepole pine in the south-central Oregon pumice zone

  Background information is presented that provides historical perspectives on the field of mycology in the Pacific Northwest and its role in forest management. The series of events and decisions that have ...

  Citation × Citation Citation Abstract Copy Title: Examining ectomycorrhizal communities of ponderosa pine and lodgepole pine in the south-central Oregon pumice zone Author: Garcia, Maria Osuna Background information is presented that provides historical perspectives on the field of mycology in the Pacific Northwest and its role in forest management. The series of events and decisions that have led to previous studies (or lack of studies) in the field also dictate the directions of current research. Culture, philosophy, and history all play a role in the questions that may be asked today. Examining the past gives light to the questions that are asked in the present and future. Forest ecosystems of the Pacific Northwest are changing as a result of climate change. Rise of global temperatures, decline of winter precipitation, earlier loss of snowpack, and increased summer drought are altering the range of Pinus contorta. As environmental conditions change, Pinus ponderosa may establish within the historic Pinus contorta range. Successful pine species migration will be constrained by the distribution or co-migration of ectomycorrhizal fungi (EMF). Knowledge of the linkages among soil fungal diversity, community structure, and environmental factors is critical to understanding the organization and stability of pine ecosystems. The objectives of this study are to establish an informational foundation of the EMF communities of P. ponderosa and P. contorta in the Deschutes National Forest and to examine soil characteristics associated with community composition. We examined EMF root tips of P. ponderosa and P. contorta in soil cores and conducted soil chemistry analysis for P. ponderosa. Results indicate that Cenococcum geophilum, Rhizopogon salebrosus, and Inocybe flocculosa are dominant in both P. contorta and P. ponderosa soil cores. Rhizopogon spp. were ubiquitous in P. ponderosa. There was no significant difference between EMF communities of P. ponderosa and P. contorta at the species level. Ordination analysis suggests that pH, Bray-phosphorus, total phosphorus (P), carbon (C), mineralizable nitrogen (N), ammonium (NH₄) and nitrate (NO₃) are driving EMF community composition in P. ponderosa. We found a significant linear relationship between EMF species richness and mineralizable N. Title: Examining ectomycorrhizal communities of ponderosa pine and lodgepole pine in the south-central Oregon pumice zone Author: Garcia, Maria Osuna Background information is presented that provides historical perspectives on the field of mycology in the Pacific Northwest and its role in forest management. The series of events and decisions that have led to previous studies (or lack of studies) in the field also dictate the directions of current research. Culture, philosophy, and history all play a role in the questions that may be asked today. Examining the past gives light to the questions that are asked in the present and future. Forest ecosystems of the Pacific Northwest are changing as a result of climate change. Rise of global temperatures, decline of winter precipitation, earlier loss of snowpack, and increased summer drought are altering the range of Pinus contorta. As environmental conditions change, Pinus ponderosa may establish within the historic Pinus contorta range. Successful pine species migration will be constrained by the distribution or co-migration of ectomycorrhizal fungi (EMF). Knowledge of the linkages among soil fungal diversity, community structure, and environmental factors is critical to understanding the organization and stability of pine ecosystems. The objectives of this study are to establish an informational foundation of the EMF communities of P. ponderosa and P. contorta in the Deschutes National Forest and to examine soil characteristics associated with community composition. We examined EMF root tips of P. ponderosa and P. contorta in soil cores and conducted soil chemistry analysis for P. ponderosa. Results indicate that Cenococcum geophilum, Rhizopogon salebrosus, and Inocybe flocculosa are dominant in both P. contorta and P. ponderosa soil cores. Rhizopogon spp. were ubiquitous in P. ponderosa. There was no significant difference between EMF communities of P. ponderosa and P. contorta at the species level. Ordination analysis suggests that pH, Bray-phosphorus, total phosphorus (P), carbon (C), mineralizable nitrogen (N), ammonium (NH₄) and nitrate (NO₃) are driving EMF community composition in P. ponderosa. We found a significant linear relationship between EMF species richness and mineralizable N. Close

• 58. [Article] Using soil data to enhance modeling of forest responses to climate change

  The over-arching theme of this work is that soil data affect the performance and realism of vegetation models with particular focus on their ability to predict or explain disturbances such as fire or disease. ...

  Citation × Citation Citation Abstract Copy Title: Using soil data to enhance modeling of forest responses to climate change Author: Peterman, Wendy L. The over-arching theme of this work is that soil data affect the performance and realism of vegetation models with particular focus on their ability to predict or explain disturbances such as fire or disease. We tested the sensitivity of the Excel version of the 3-PG model to soil properties and applied this information to understanding bark beetle attacks in drought-stressed forests. We tested the sensitivity of the MC2 model to soil depth with a particular focus on how soils affect the biogeochemistry and fire modules of the Dynamic Global Vegetation Model (DGVM). We found in these sensitivity analyses, soil depth, soil water storage capacity (ASW) and soil texture are among the most important soil factors to map and include in models of forest productivity. Chapter 2 shows how soil available water storage capacity has an effect on where pinyon pines are most likely to be stressed during a drought that lasts longer than one year. Chapter 3 shows how ponderosa pines in western Montana are more vulnerable to disturbance on fine-textured soils during years when precipitation is significantly less than in previous years. Finally, Chapter 4 shows that changes in soil depth affect model simulations of productivity and hydrology across the landscape, but fire simulations are only affected in areas with lower precipitation. The value of this research is the knowledge that soil characteristics such as depth, ASW, soil fertility and soil texture can be used in hindcasts of forest disturbances to determine thresholds where forests may become more vulnerable to disturbance in response to rising temperatures or changes in precipitation. Title: Using soil data to enhance modeling of forest responses to climate change Author: Peterman, Wendy L. The over-arching theme of this work is that soil data affect the performance and realism of vegetation models with particular focus on their ability to predict or explain disturbances such as fire or disease. We tested the sensitivity of the Excel version of the 3-PG model to soil properties and applied this information to understanding bark beetle attacks in drought-stressed forests. We tested the sensitivity of the MC2 model to soil depth with a particular focus on how soils affect the biogeochemistry and fire modules of the Dynamic Global Vegetation Model (DGVM). We found in these sensitivity analyses, soil depth, soil water storage capacity (ASW) and soil texture are among the most important soil factors to map and include in models of forest productivity. Chapter 2 shows how soil available water storage capacity has an effect on where pinyon pines are most likely to be stressed during a drought that lasts longer than one year. Chapter 3 shows how ponderosa pines in western Montana are more vulnerable to disturbance on fine-textured soils during years when precipitation is significantly less than in previous years. Finally, Chapter 4 shows that changes in soil depth affect model simulations of productivity and hydrology across the landscape, but fire simulations are only affected in areas with lower precipitation. The value of this research is the knowledge that soil characteristics such as depth, ASW, soil fertility and soil texture can be used in hindcasts of forest disturbances to determine thresholds where forests may become more vulnerable to disturbance in response to rising temperatures or changes in precipitation. Close

• 59. [Article] Development of a hydrologic model to explore impacts of climate change on water resources in the Big Wood Basin, Idaho

  In the Western United States where 50-70% of annual precipitation comes in the form of winter snowfall, water supplies may be particularly sensitive to a warming climate. We worked with a network of stakeholders ...

  Citation × Citation Citation Abstract Copy Title: Development of a hydrologic model to explore impacts of climate change on water resources in the Big Wood Basin, Idaho Author: Inouye, Allison Marshall In the Western United States where 50-70% of annual precipitation comes in the form of winter snowfall, water supplies may be particularly sensitive to a warming climate. We worked with a network of stakeholders in the Big Wood Basin, Idaho, to explore how climate change may affect water resources and identify strategies that may help mitigate the impacts. The 8,300 square kilometer region in central Idaho contains a mixture of public and private land ownership, a diversity of landcover ranging from steep forested headwaters to expansive desert shrublands to a concentrated area of urban development that has experienced a quadrupling of population since the 1970s. With nearly 60% of precipitation falling as winter snow, stakeholders expressed concern regarding the vulnerability of the quantity and timing of seasonal snowpack as well as surface water supplies used primarily for agricultural irrigation under projected climate change. Here, we achieve two objectives. The first is the development of a hydrologic model to represent the dynamics of the surface water system in the Big Wood Basin. We use the semi-distributed model Envision-Flow to represent surface water hydrology, reservoir operations, and agricultural irrigation. We calibrated the model using a multi-criteria objective function that considered three metrics related to streamflow and one metric related to snow water equivalent. The model achieved higher an efficiency of 0.74 for the main stem of the Big Wood River and 0.50 for the Camas Creek tributary during the validation period. The second objective is an analysis of the Big Wood Basin hydrology under alternative future climate scenarios. We forced the calibrated model with three downscaled CMIP5 climate model inputs representing a range of possible future conditions over the period 2010-2070. The climate models simulate an increase in basin average annual air temperature ranging from 1.6-5.7oC in the 2060s compared to the 1980-2009 average. The climate models show less of a clear trend regarding precipitation but in general, one model simulates precipitation patterns similar to historic, one is slightly wetter than historic, and one is slightly drier than historic by the mid-21st century. Under these future climate scenarios, the depth of April 1 SWE may decline by as much as 92% in the 2060s compared to the historic average. Mid to high elevations exhibit the largest reductions in SWE. Simulated streamflows show a shift in timing, with peak flows occurring up to three weeks earlier and center of timing from two to seven weeks earlier in the 2050-2069 period compared to the historic period. Reduced peak flows of 14-70% were simulated by mid-century. The simulated total annual streamflow, though, fell within the historic interquartile range for most years in the future period. These and other metrics considered suggest that the surface water hydrology of the Big Wood Basin is likely to be impacted by climate change. If the natural water storage provided by the annual snowpack is reduced and timing of streamflows shifts, water resource use and management may need to change in the future. This work provides a foundation from which to explore alternative management scenarios. The approach used here can be transferred to other watersheds to further assess how water resources may be affected by climate change. Title: Development of a hydrologic model to explore impacts of climate change on water resources in the Big Wood Basin, Idaho Author: Inouye, Allison Marshall In the Western United States where 50-70% of annual precipitation comes in the form of winter snowfall, water supplies may be particularly sensitive to a warming climate. We worked with a network of stakeholders in the Big Wood Basin, Idaho, to explore how climate change may affect water resources and identify strategies that may help mitigate the impacts. The 8,300 square kilometer region in central Idaho contains a mixture of public and private land ownership, a diversity of landcover ranging from steep forested headwaters to expansive desert shrublands to a concentrated area of urban development that has experienced a quadrupling of population since the 1970s. With nearly 60% of precipitation falling as winter snow, stakeholders expressed concern regarding the vulnerability of the quantity and timing of seasonal snowpack as well as surface water supplies used primarily for agricultural irrigation under projected climate change. Here, we achieve two objectives. The first is the development of a hydrologic model to represent the dynamics of the surface water system in the Big Wood Basin. We use the semi-distributed model Envision-Flow to represent surface water hydrology, reservoir operations, and agricultural irrigation. We calibrated the model using a multi-criteria objective function that considered three metrics related to streamflow and one metric related to snow water equivalent. The model achieved higher an efficiency of 0.74 for the main stem of the Big Wood River and 0.50 for the Camas Creek tributary during the validation period. The second objective is an analysis of the Big Wood Basin hydrology under alternative future climate scenarios. We forced the calibrated model with three downscaled CMIP5 climate model inputs representing a range of possible future conditions over the period 2010-2070. The climate models simulate an increase in basin average annual air temperature ranging from 1.6-5.7oC in the 2060s compared to the 1980-2009 average. The climate models show less of a clear trend regarding precipitation but in general, one model simulates precipitation patterns similar to historic, one is slightly wetter than historic, and one is slightly drier than historic by the mid-21st century. Under these future climate scenarios, the depth of April 1 SWE may decline by as much as 92% in the 2060s compared to the historic average. Mid to high elevations exhibit the largest reductions in SWE. Simulated streamflows show a shift in timing, with peak flows occurring up to three weeks earlier and center of timing from two to seven weeks earlier in the 2050-2069 period compared to the historic period. Reduced peak flows of 14-70% were simulated by mid-century. The simulated total annual streamflow, though, fell within the historic interquartile range for most years in the future period. These and other metrics considered suggest that the surface water hydrology of the Big Wood Basin is likely to be impacted by climate change. If the natural water storage provided by the annual snowpack is reduced and timing of streamflows shifts, water resource use and management may need to change in the future. This work provides a foundation from which to explore alternative management scenarios. The approach used here can be transferred to other watersheds to further assess how water resources may be affected by climate change. Close

• 60. [Article] Local perceptions of climate change, coping and adaptation strategies among smallholder farmers in the Lake Basin Region of Kenya

  Smallholder farmers in Africa, who have long relied on rain-fed agriculture, are currently experiencing adverse impacts of climate change which is posing serious challenges to their ability to sustain ...

  Citation × Citation Citation Abstract Copy Title: Local perceptions of climate change, coping and adaptation strategies among smallholder farmers in the Lake Basin Region of Kenya Author: Asinjo, Robert Smallholder farmers in Africa, who have long relied on rain-fed agriculture, are currently experiencing adverse impacts of climate change which is posing serious challenges to their ability to sustain their livelihoods (Morton 2007). This is the case for many other areas around the world, especially among indigenousor ruralcommunities who rely directly on natural resources. Little is understood about the day-to-day impacts felt in many of these communities, impacts that vary considerably, based on location. Little still, is understood about the strategies that individuals or communities are adopting in order to cope and adapt, strategies that can be expected to vary based on the social and cultural context of specific communities (Crate & Nuttall 2009). Discourses around climate change have been dominated mainly by scientists and policy makers who, in their considerations, pay more attention tothe biophysical aspects of climate variability. Consequently, strategies to address climate change are centered on mitigation of greenhouse gas emissions, a major concern in the industrialized world (Orlove et al. 2010, Berkes 2007). However it is projected that greenhouse gases already present in the atmosphere, will result in increasing climate variability and extreme events such as droughts and rising temperatures among others. Communities in the non-industrialized world have contributed the least to greenhouse gases, yet they are disproportionately vulnerable to the adverse impacts of climate change (Kangalawe 2011). Given the broad scale of climate change, the resulting impacts affect many aspects of peoples' livelihoods. Hence there is a need for moreplace-based studies that highlight the human dimensions of climate change. Considering human dimensions provides to a better understanding of the links between perceptions of climate change, local knowledge and responses to climate change. This approach is adopted in this research study, which focuses on smallholder farmers in Rusinga Island located in Kenya's Lake Victoria basin. The main aim is to understand how they perceive climate change and in turn the strategies they are employing as they confront uncertain climatic conditions. The study is centered on the individual practices of local farmers as well as communal action aimed at enhancing their resilience to climate change. The approach is integrative seeking to understand the coping and adaptation strategies favored by farmers within the specific sociocultural context in Rusinga Island. Title: Local perceptions of climate change, coping and adaptation strategies among smallholder farmers in the Lake Basin Region of Kenya Author: Asinjo, Robert Smallholder farmers in Africa, who have long relied on rain-fed agriculture, are currently experiencing adverse impacts of climate change which is posing serious challenges to their ability to sustain their livelihoods (Morton 2007). This is the case for many other areas around the world, especially among indigenousor ruralcommunities who rely directly on natural resources. Little is understood about the day-to-day impacts felt in many of these communities, impacts that vary considerably, based on location. Little still, is understood about the strategies that individuals or communities are adopting in order to cope and adapt, strategies that can be expected to vary based on the social and cultural context of specific communities (Crate & Nuttall 2009). Discourses around climate change have been dominated mainly by scientists and policy makers who, in their considerations, pay more attention tothe biophysical aspects of climate variability. Consequently, strategies to address climate change are centered on mitigation of greenhouse gas emissions, a major concern in the industrialized world (Orlove et al. 2010, Berkes 2007). However it is projected that greenhouse gases already present in the atmosphere, will result in increasing climate variability and extreme events such as droughts and rising temperatures among others. Communities in the non-industrialized world have contributed the least to greenhouse gases, yet they are disproportionately vulnerable to the adverse impacts of climate change (Kangalawe 2011). Given the broad scale of climate change, the resulting impacts affect many aspects of peoples' livelihoods. Hence there is a need for moreplace-based studies that highlight the human dimensions of climate change. Considering human dimensions provides to a better understanding of the links between perceptions of climate change, local knowledge and responses to climate change. This approach is adopted in this research study, which focuses on smallholder farmers in Rusinga Island located in Kenya's Lake Victoria basin. The main aim is to understand how they perceive climate change and in turn the strategies they are employing as they confront uncertain climatic conditions. The study is centered on the individual practices of local farmers as well as communal action aimed at enhancing their resilience to climate change. The approach is integrative seeking to understand the coping and adaptation strategies favored by farmers within the specific sociocultural context in Rusinga Island. Close

• 61. [Article] Improving Projections of Tidal Marsh Persistence under Climate Change with Remote Sensing and Site-Specific Data

  Tidal marshes are dynamic ecosystems that are threatened by climate change and sea-level rise. To characterize baseline condition and historic climate sensitivities, and improve projections into the future, ...

  Citation × Citation Citation Abstract Copy Title: Improving Projections of Tidal Marsh Persistence under Climate Change with Remote Sensing and Site-Specific Data Author: Buffington, Kevin John Tidal marshes are dynamic ecosystems that are threatened by climate change and sea-level rise. To characterize baseline condition and historic climate sensitivities, and improve projections into the future, new methods are required that integrate data from the field and remote sensing platforms. Marsh elevation response models can be calibrated with site-specific data to determine the vulnerability of a marsh to sea-level rise and help guide management decisions. Elevation models are sensitive to initial elevation, the rate of accretion, and aboveground biomass. The overarching goal of this dissertation was to develop techniques to improve these important model inputs and evaluate the range of spatial and temporal variation. Light detection and ranging (lidar) is an invaluable tool for collecting elevation data, however dense vegetation prevents the accurate measurement of the tidal marsh surface. In Chapter 2, I describe the development of a technique to calibrate lidar digital elevation models with survey elevation data using readily available multispectral aerial imagery from the National Agricultural Inventory Program (NAIP). Using survey elevation data across 17 Pacific Coast tidal marshes, I demonstrated the utility of the Lidar Elevation Adjustment with NDVI (LEAN) technique to account for the positive bias in lidar due to vegetation. LEAN reduced error from an average of 23.1 cm to 7.2 cm root mean squared error and removed the positive bias caused by vegetation. This increase in accuracy will facilitate more accurate assessments of current and future vulnerability to sea-level rise. The phenology of aboveground biomass in tidal marsh plants in relation to climate variation has not been explored in the Pacific Northwest (PNW). In Chapter 3 I explain how I leveraged the Landsat archive and cloud computing capabilities to assess how Tasseled Cap Greenness (TCG, a proxy for aboveground biomass) in three PNW tidal marshes has responded to recent variation in climate to characterize sensitivity to climate change. Through analysis of over 3700 Landsat images obtained from 1984-2015, I found increased annual precipitation resulted in a higher peak TCG, while warmer May temperatures resulted in an earlier day of peak TCG. These results also demonstrate how time-series analysis of remote sensing data can be used to examine the sensitivity of tidal marsh plants to climate variability and directional change. The range of variation in tidal marsh accretion rates has not been characterized across the PNW. For Chapter 4, I collected and analyzed twenty-two soil cores from eight estuaries to estimate historic accretion rates with radioisotope dating techniques and evaluated the amount and source of variation across estuaries. I found that tidal marshes across the PNW had accretion rates greater than the current rate of sea-level rise, ranging from 2.3 – 7.3 mm yr⁻¹. Using a watershed-scale analysis, I found that long-term average annual fluvial discharge was the top predictor of tidal marsh accretion rates. Additionally, I found that calibrating the Wetland Accretion Rate Model for Ecosystem Resilience (WARMER) with accretion rate data from nearby estuaries can result in uncertainties of up to 41% (50 cm) after 100 years. Finally, in Chapter 5, I demonstrate that a range of 62 cm of error is possible in WARMER models after a 100 year simulation when both uncorrected lidar and non-local accretion rates are used, fundamentally changing the interpretation of the results. Altogether, this dissertation illustrates the importance of collecting site-specific wetland vegetation and elevation data and demonstrates how lidar and multispectral remote sensing data can be leveraged to improve our understanding of how climate variability and change impacts coastal ecosystems. Title: Improving Projections of Tidal Marsh Persistence under Climate Change with Remote Sensing and Site-Specific Data Author: Buffington, Kevin John Tidal marshes are dynamic ecosystems that are threatened by climate change and sea-level rise. To characterize baseline condition and historic climate sensitivities, and improve projections into the future, new methods are required that integrate data from the field and remote sensing platforms. Marsh elevation response models can be calibrated with site-specific data to determine the vulnerability of a marsh to sea-level rise and help guide management decisions. Elevation models are sensitive to initial elevation, the rate of accretion, and aboveground biomass. The overarching goal of this dissertation was to develop techniques to improve these important model inputs and evaluate the range of spatial and temporal variation. Light detection and ranging (lidar) is an invaluable tool for collecting elevation data, however dense vegetation prevents the accurate measurement of the tidal marsh surface. In Chapter 2, I describe the development of a technique to calibrate lidar digital elevation models with survey elevation data using readily available multispectral aerial imagery from the National Agricultural Inventory Program (NAIP). Using survey elevation data across 17 Pacific Coast tidal marshes, I demonstrated the utility of the Lidar Elevation Adjustment with NDVI (LEAN) technique to account for the positive bias in lidar due to vegetation. LEAN reduced error from an average of 23.1 cm to 7.2 cm root mean squared error and removed the positive bias caused by vegetation. This increase in accuracy will facilitate more accurate assessments of current and future vulnerability to sea-level rise. The phenology of aboveground biomass in tidal marsh plants in relation to climate variation has not been explored in the Pacific Northwest (PNW). In Chapter 3 I explain how I leveraged the Landsat archive and cloud computing capabilities to assess how Tasseled Cap Greenness (TCG, a proxy for aboveground biomass) in three PNW tidal marshes has responded to recent variation in climate to characterize sensitivity to climate change. Through analysis of over 3700 Landsat images obtained from 1984-2015, I found increased annual precipitation resulted in a higher peak TCG, while warmer May temperatures resulted in an earlier day of peak TCG. These results also demonstrate how time-series analysis of remote sensing data can be used to examine the sensitivity of tidal marsh plants to climate variability and directional change. The range of variation in tidal marsh accretion rates has not been characterized across the PNW. For Chapter 4, I collected and analyzed twenty-two soil cores from eight estuaries to estimate historic accretion rates with radioisotope dating techniques and evaluated the amount and source of variation across estuaries. I found that tidal marshes across the PNW had accretion rates greater than the current rate of sea-level rise, ranging from 2.3 – 7.3 mm yr⁻¹. Using a watershed-scale analysis, I found that long-term average annual fluvial discharge was the top predictor of tidal marsh accretion rates. Additionally, I found that calibrating the Wetland Accretion Rate Model for Ecosystem Resilience (WARMER) with accretion rate data from nearby estuaries can result in uncertainties of up to 41% (50 cm) after 100 years. Finally, in Chapter 5, I demonstrate that a range of 62 cm of error is possible in WARMER models after a 100 year simulation when both uncorrected lidar and non-local accretion rates are used, fundamentally changing the interpretation of the results. Altogether, this dissertation illustrates the importance of collecting site-specific wetland vegetation and elevation data and demonstrates how lidar and multispectral remote sensing data can be leveraged to improve our understanding of how climate variability and change impacts coastal ecosystems. Close

• 62. [Article] Debris flows in glaciated catchments : a case study on Mount Rainier, Washington

  Debris flows, which occur in mountain settings worldwide, have been particularly damaging in the glaciated basins flanking the stratovolcanoes in the Cascade Range of the northwestern United States. This ...

  Citation × Citation Citation Abstract Copy Title: Debris flows in glaciated catchments : a case study on Mount Rainier, Washington Author: Legg, Nicholas T. Debris flows, which occur in mountain settings worldwide, have been particularly damaging in the glaciated basins flanking the stratovolcanoes in the Cascade Range of the northwestern United States. This thesis contains two manuscripts that respectively investigate the (1) initiation processes of debris flows in these glaciated catchments, and (2) debris flow occurrence and its effect on valley bottoms over the last thousand years. In a 2006 storm, seven debris flows initiated from proglacial gullies of separate basins on the flanks of Mount Rainier. Gully heads at glacier termini and distributed collapse of gully walls imply that clear water was transformed to debris flow through progressive addition of sediment along gully lengths. In the first study, we analyze gully changes, reconstruct runoff conditions, and assess spatial distributions of debris flows to infer the processes and conditions necessary for debris flow initiation in glaciated catchments. Gully measurements suggest that sediment bulking requires steep gradients, abundant unstable material, and sufficient gully length. Reconstruction of runoff generated during the storm suggests that glaciers are important for generating the runoff necessary for debris flow initiation, particularly because infiltration capacities on glacial till covered surfaces well exceed measured rainfall rates. Runoff generation from glaciers and abundant loose debris at their termini explain why all debris flows in the storm initiated from proglacial areas. Proglacial areas that produced debris flows have steeper drainage networks with significantly higher elevations and lower drainage areas, suggesting that debris flows are associated with high elevation glaciers with relatively steep proglacial areas. This correlation reflects positive slope-elevation trends for the Mount Rainier volcano. An indirect effect of glacier change is thus the change in the distribution of ice-free slopes, which influence a basin’s debris flow potential. These findings have implications for projections of debris flow activity in basins experiencing glacier change. The second study uses a variety of dating techniques to reconstruct a chronology of debris flows in the Kautz Creek valley on the southwest flank of Mount Rainier (Washington). Dendrochronologic dating of growth disturbances combined with lichenometric techniques constrained five debris flow ages from 1712 to 1915 AD. We also estimated ages of three debris flows ranging in age from ca. 970 to 1661. Run-out distances served as a proxy for debris flow magnitude, and indicate that at least 11, 2, and 1 debris flow(s) have traveled at least 1, 3, and 5 km from the valley head, respectively since ca. 1650. Valley form reflects the frequency-magnitude relationship indicated by the chronology. In the upper, relatively steep valley, discrete debris flow snouts and secondary channels are abundant, suggesting a process of debris flow conveyance, channel plugging, and channel avulsion. The lower valley is characterized by relatively smooth surfaces, an absence of bouldery debris flow snouts, few secondary channels, and relatively old surface ages inferred from the presence of tephra layers. We infer that the lower valley is deposited on by relatively infrequent, large magnitude, low-yield strength debris flows like an event in 1947, which deposited wide, tabular lobes of debris outside of the main channel. Debris flows during the Little Ice Age (LIA) predominantly traveled no further than the upper valley. Stratigraphic evidence suggests that the main Kautz Creek channel was filled during the LIA, enhancing debris flow deposition on the valley surface and perhaps reducing run-out lengths. Diminished areas and gradients in front of glaciers during the LIA also likely contributed to decreased run-out lengths. These findings suggest that changes in debris flow source and depositional zones resulting from temperature and glacier cycles influence the magnitude and run-out distances of debris flows, and the dynamics of deposition in valley bottoms. Title: Debris flows in glaciated catchments : a case study on Mount Rainier, Washington Author: Legg, Nicholas T. Debris flows, which occur in mountain settings worldwide, have been particularly damaging in the glaciated basins flanking the stratovolcanoes in the Cascade Range of the northwestern United States. This thesis contains two manuscripts that respectively investigate the (1) initiation processes of debris flows in these glaciated catchments, and (2) debris flow occurrence and its effect on valley bottoms over the last thousand years. In a 2006 storm, seven debris flows initiated from proglacial gullies of separate basins on the flanks of Mount Rainier. Gully heads at glacier termini and distributed collapse of gully walls imply that clear water was transformed to debris flow through progressive addition of sediment along gully lengths. In the first study, we analyze gully changes, reconstruct runoff conditions, and assess spatial distributions of debris flows to infer the processes and conditions necessary for debris flow initiation in glaciated catchments. Gully measurements suggest that sediment bulking requires steep gradients, abundant unstable material, and sufficient gully length. Reconstruction of runoff generated during the storm suggests that glaciers are important for generating the runoff necessary for debris flow initiation, particularly because infiltration capacities on glacial till covered surfaces well exceed measured rainfall rates. Runoff generation from glaciers and abundant loose debris at their termini explain why all debris flows in the storm initiated from proglacial areas. Proglacial areas that produced debris flows have steeper drainage networks with significantly higher elevations and lower drainage areas, suggesting that debris flows are associated with high elevation glaciers with relatively steep proglacial areas. This correlation reflects positive slope-elevation trends for the Mount Rainier volcano. An indirect effect of glacier change is thus the change in the distribution of ice-free slopes, which influence a basin’s debris flow potential. These findings have implications for projections of debris flow activity in basins experiencing glacier change. The second study uses a variety of dating techniques to reconstruct a chronology of debris flows in the Kautz Creek valley on the southwest flank of Mount Rainier (Washington). Dendrochronologic dating of growth disturbances combined with lichenometric techniques constrained five debris flow ages from 1712 to 1915 AD. We also estimated ages of three debris flows ranging in age from ca. 970 to 1661. Run-out distances served as a proxy for debris flow magnitude, and indicate that at least 11, 2, and 1 debris flow(s) have traveled at least 1, 3, and 5 km from the valley head, respectively since ca. 1650. Valley form reflects the frequency-magnitude relationship indicated by the chronology. In the upper, relatively steep valley, discrete debris flow snouts and secondary channels are abundant, suggesting a process of debris flow conveyance, channel plugging, and channel avulsion. The lower valley is characterized by relatively smooth surfaces, an absence of bouldery debris flow snouts, few secondary channels, and relatively old surface ages inferred from the presence of tephra layers. We infer that the lower valley is deposited on by relatively infrequent, large magnitude, low-yield strength debris flows like an event in 1947, which deposited wide, tabular lobes of debris outside of the main channel. Debris flows during the Little Ice Age (LIA) predominantly traveled no further than the upper valley. Stratigraphic evidence suggests that the main Kautz Creek channel was filled during the LIA, enhancing debris flow deposition on the valley surface and perhaps reducing run-out lengths. Diminished areas and gradients in front of glaciers during the LIA also likely contributed to decreased run-out lengths. These findings suggest that changes in debris flow source and depositional zones resulting from temperature and glacier cycles influence the magnitude and run-out distances of debris flows, and the dynamics of deposition in valley bottoms. Close