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• 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