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• 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