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• 1. [Article] Emergent thermodynamics in a system of macroscopic, chaotic surface waves

  The properties of conventional materials are inextricably linked with their molecular composition; to make water flow like wine would require changing its molecular identity. To circumvent this restriction, ...

  Citation × Citation Citation Abstract Copy Title: Emergent thermodynamics in a system of macroscopic, chaotic surface waves Author: Welch, Kyle Year: 2016 The properties of conventional materials are inextricably linked with their molecular composition; to make water flow like wine would require changing its molecular identity. To circumvent this restriction, I have contstructed and characterized a two-dimensional metafluid, so-called because its constitutive dynamics are derived not from atoms and molecules but from macroscopic, chaotic surface waves excited on a vertically agitated fluid. Unlike in conventional fluids, the viscosity and temperature of this metafluid are independantly tunable. Despite this unconventional property, our system is surprisingly consistent with equilibrium thermodynamics, despite being constructed from macroscopic, non-equilibrium elements. As a programmable material, our metafluid represents a new platform on which to study complex phenomena such as self-assembly and pattern formation. We demonstrate one such application in our study of short-chain polymer analogs embedded in our system. Title: Emergent thermodynamics in a system of macroscopic, chaotic surface waves Author: Welch, Kyle Year: 2016 The properties of conventional materials are inextricably linked with their molecular composition; to make water flow like wine would require changing its molecular identity. To circumvent this restriction, I have contstructed and characterized a two-dimensional metafluid, so-called because its constitutive dynamics are derived not from atoms and molecules but from macroscopic, chaotic surface waves excited on a vertically agitated fluid. Unlike in conventional fluids, the viscosity and temperature of this metafluid are independantly tunable. Despite this unconventional property, our system is surprisingly consistent with equilibrium thermodynamics, despite being constructed from macroscopic, non-equilibrium elements. As a programmable material, our metafluid represents a new platform on which to study complex phenomena such as self-assembly and pattern formation. We demonstrate one such application in our study of short-chain polymer analogs embedded in our system. Close

• 2. [Article] MORPHOLOGICAL VARIATION OF PISASTER OCHRACEUS IN RESPONSE TO WAVE EXPOSURE

  52 pages. A thesis presented to the Department of Biology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2...

  Citation × Citation Citation Abstract Copy Title: MORPHOLOGICAL VARIATION OF PISASTER OCHRACEUS IN RESPONSE TO WAVE EXPOSURE Author: Bjorkquist, Alyssa Year: 2016 52 pages. A thesis presented to the Department of Biology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2016. Title: MORPHOLOGICAL VARIATION OF PISASTER OCHRACEUS IN RESPONSE TO WAVE EXPOSURE Author: Bjorkquist, Alyssa Year: 2016 52 pages. A thesis presented to the Department of Biology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2016. Close

• 3. [Article] A Hierarchical Modeling Approach to Simulating the Geomorphic Response of River Systems to Climate Change

  Anthropogenic climate change significantly affects water resources. River flows in mountainous regions are driven by snowmelt and are therefore highly sensitive to increases in temperature resulting from ...

  Citation × Citation Citation Abstract Copy Title: A Hierarchical Modeling Approach to Simulating the Geomorphic Response of River Systems to Climate Change Author: Praskievicz, Sarah Year: 2014 Anthropogenic climate change significantly affects water resources. River flows in mountainous regions are driven by snowmelt and are therefore highly sensitive to increases in temperature resulting from climate change. Climate-driven hydrological changes are potentially significant for the fluvial geomorphology of river systems. In unchanging climatic and tectonic conditions, a river's morphology will develop in equilibrium with inputs of water and sediment, but climate change represents a potential forcing on these variables that may push the system into disequilibrium and cause significant changes in river morphology. Geomorphic factors, such as channel geometry, planform, and sediment transport, are major determinants of the value of river systems, including their suitability for threatened and endangered species and for human uses of water. This dissertation research uses a hierarchical modeling approach to investigate potential impacts of anthropogenic climate change on river morphology in the interior Pacific Northwest. The research will address the following theoretical and methodological objectives: 1) Develop downscaled climate change scenarios, based on regional climate-model output, including changes in daily minimum and maximum temperature and precipitation. 2) Estimate how climate change scenarios affect river discharge and suspended-sediment load, using a basin-scale hydrologic model. 3) Examine potential impacts of climate-driven hydrologic changes on stream power and shear stress, bedload sediment transport, and river morphology, including channel geometry and planform. The downscaling approach, based on empirically-estimated local topographic lapse rates, produces high-resolution climate grids with positive forecast skill. The hydrologic modeling results indicate that projected climate change in the study rivers will change the annual cycle of hydrology, with increased winter discharge, a decrease in the magnitude of the spring snowmelt peak, and decreased summer discharge. Geomorphic modeling results suggest that changes in reach-averaged bedload transport are highly sensitive to likely changes in the recurrence interval of the critical discharge needed to mobilize bed sediments. This dissertation research makes an original contribution to the climate-change impacts literature by linking Earth processes across a wide range of spatial scales to project changes in river systems that may be significant for management of these systems for societal and ecological benefits. This dissertation includes unpublished co-authored material. Title: A Hierarchical Modeling Approach to Simulating the Geomorphic Response of River Systems to Climate Change Author: Praskievicz, Sarah Year: 2014 Anthropogenic climate change significantly affects water resources. River flows in mountainous regions are driven by snowmelt and are therefore highly sensitive to increases in temperature resulting from climate change. Climate-driven hydrological changes are potentially significant for the fluvial geomorphology of river systems. In unchanging climatic and tectonic conditions, a river's morphology will develop in equilibrium with inputs of water and sediment, but climate change represents a potential forcing on these variables that may push the system into disequilibrium and cause significant changes in river morphology. Geomorphic factors, such as channel geometry, planform, and sediment transport, are major determinants of the value of river systems, including their suitability for threatened and endangered species and for human uses of water. This dissertation research uses a hierarchical modeling approach to investigate potential impacts of anthropogenic climate change on river morphology in the interior Pacific Northwest. The research will address the following theoretical and methodological objectives: 1) Develop downscaled climate change scenarios, based on regional climate-model output, including changes in daily minimum and maximum temperature and precipitation. 2) Estimate how climate change scenarios affect river discharge and suspended-sediment load, using a basin-scale hydrologic model. 3) Examine potential impacts of climate-driven hydrologic changes on stream power and shear stress, bedload sediment transport, and river morphology, including channel geometry and planform. The downscaling approach, based on empirically-estimated local topographic lapse rates, produces high-resolution climate grids with positive forecast skill. The hydrologic modeling results indicate that projected climate change in the study rivers will change the annual cycle of hydrology, with increased winter discharge, a decrease in the magnitude of the spring snowmelt peak, and decreased summer discharge. Geomorphic modeling results suggest that changes in reach-averaged bedload transport are highly sensitive to likely changes in the recurrence interval of the critical discharge needed to mobilize bed sediments. This dissertation research makes an original contribution to the climate-change impacts literature by linking Earth processes across a wide range of spatial scales to project changes in river systems that may be significant for management of these systems for societal and ecological benefits. This dissertation includes unpublished co-authored material. Close

• 4. [Article] Paying the water bill : community support for agriculture and river restoration in central Oregon

  2 pages

  Citation × Citation Citation Abstract Copy Title: Paying the water bill : community support for agriculture and river restoration in central Oregon Author: University of Oregon. Ecosystem Workforce Program Year: 2016, 2013 2 pages Title: Paying the water bill : community support for agriculture and river restoration in central Oregon Author: University of Oregon. Ecosystem Workforce Program Year: 2016, 2013 2 pages Close

• 5. [Article] EFFECTS OF ACUTE PASSIVE HEAT EXPOSURE

  42 pages. A thesis presented to the Department of Human Physiology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, ...

  Citation × Citation Citation Abstract Copy Title: EFFECTS OF ACUTE PASSIVE HEAT EXPOSURE Author: Harris, Sarianne Year: 2016 42 pages. A thesis presented to the Department of Human Physiology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2016. Title: EFFECTS OF ACUTE PASSIVE HEAT EXPOSURE Author: Harris, Sarianne Year: 2016 42 pages. A thesis presented to the Department of Human Physiology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2016. Close

• 6. [Article] Protecting Stream Ecosystem Health in the Face of Rapid Urbanization and Climate Change

  The ability to anticipate and evaluate the combined impacts of urbanization and climate change on streamflow regimes is critical to developing proactive strategies that protect aquatic ecosystems. I developed ...

  Citation × Citation Citation Abstract Copy Title: Protecting Stream Ecosystem Health in the Face of Rapid Urbanization and Climate Change Author: Wu, Hong Year: 2015 The ability to anticipate and evaluate the combined impacts of urbanization and climate change on streamflow regimes is critical to developing proactive strategies that protect aquatic ecosystems. I developed an interdisciplinary modeling framework to compare and contrast the effectiveness of integrated stormwater management, or its absence, with two regional growth patterns for maintaining streamflow regimes in the context of climate change. In three adjacent urbanizing watersheds in Oregon's Willamette Valley, I conducted a three-step sequence to: 1) simulate land use change under four future development scenarios with the agent-based model Envision; 2) model resultant hydrological change under the recent past and two future climate regimes using the Soil and Water Assessment Tool; and 3) assess scenario impacts on streamflow regimes using 10 ecologically significant flow metrics. I evaluated each scenario in each basin using a flow metric typology based on the magnitude of change in each metric and the degree to which such changes could be mitigated, i.e., insensitive, sensitive and manageable, and sensitive and resistant. My results demonstrated distinct signatures of urbanization and climate change on flow regimes. Urbanization and climate change in isolation led to significant flow alterations in all three basins. Urbanization consistently led to increases in flow regime flashiness and severity of extreme flow events, whereas climate change primarily caused a drying trend. Climate change tended to exacerbate the impacts of urbanization but also mitigated urban impacts on several metrics. The combined impacts of urbanization and climate change caused substantial changes to metric sensitivities, which further differed by basin and climate regime, highlighting the uncertainties of streamflow regime responses to development and the value of spatially explicit modeling that can reveal complex interactions between natural and human systems. Scenario comparisons demonstrated the importance of integrated stormwater management and, secondarily, compact regional growth. My findings reveal the need for regional flow-ecology research that substantiates the ecological significance of each flow metric, develops specific targets for manageable ones, and explores potential remedies for resistant ones. The interdisciplinary modeling framework shows promise as a transferable tool for local watershed management. This dissertation includes previously unpublished co-authored material. Title: Protecting Stream Ecosystem Health in the Face of Rapid Urbanization and Climate Change Author: Wu, Hong Year: 2015 The ability to anticipate and evaluate the combined impacts of urbanization and climate change on streamflow regimes is critical to developing proactive strategies that protect aquatic ecosystems. I developed an interdisciplinary modeling framework to compare and contrast the effectiveness of integrated stormwater management, or its absence, with two regional growth patterns for maintaining streamflow regimes in the context of climate change. In three adjacent urbanizing watersheds in Oregon's Willamette Valley, I conducted a three-step sequence to: 1) simulate land use change under four future development scenarios with the agent-based model Envision; 2) model resultant hydrological change under the recent past and two future climate regimes using the Soil and Water Assessment Tool; and 3) assess scenario impacts on streamflow regimes using 10 ecologically significant flow metrics. I evaluated each scenario in each basin using a flow metric typology based on the magnitude of change in each metric and the degree to which such changes could be mitigated, i.e., insensitive, sensitive and manageable, and sensitive and resistant. My results demonstrated distinct signatures of urbanization and climate change on flow regimes. Urbanization and climate change in isolation led to significant flow alterations in all three basins. Urbanization consistently led to increases in flow regime flashiness and severity of extreme flow events, whereas climate change primarily caused a drying trend. Climate change tended to exacerbate the impacts of urbanization but also mitigated urban impacts on several metrics. The combined impacts of urbanization and climate change caused substantial changes to metric sensitivities, which further differed by basin and climate regime, highlighting the uncertainties of streamflow regime responses to development and the value of spatially explicit modeling that can reveal complex interactions between natural and human systems. Scenario comparisons demonstrated the importance of integrated stormwater management and, secondarily, compact regional growth. My findings reveal the need for regional flow-ecology research that substantiates the ecological significance of each flow metric, develops specific targets for manageable ones, and explores potential remedies for resistant ones. The interdisciplinary modeling framework shows promise as a transferable tool for local watershed management. This dissertation includes previously unpublished co-authored material. Close

• 7. [Article] Forgetting Nature: The Importance of Including Environmental Flows in International Water Agreements

  34 pages

  Citation × Citation Citation Abstract Copy Title: Forgetting Nature: The Importance of Including Environmental Flows in International Water Agreements Author: Hardberger, Amy Year: 2016 34 pages Title: Forgetting Nature: The Importance of Including Environmental Flows in International Water Agreements Author: Hardberger, Amy Year: 2016 34 pages Close

• 8. [Article] Silverton Notice of Adopted Amendment (2011-08-05)

  6 pp. Adopted 2011-08-05. Department of Land Conservation and Development Notice of Adopted Amendment

  Citation × Citation Citation Abstract Copy Title: Silverton Notice of Adopted Amendment (2011-08-05) Author: Silverton Year: 2014, 2011 6 pp. Adopted 2011-08-05. Department of Land Conservation and Development Notice of Adopted Amendment Title: Silverton Notice of Adopted Amendment (2011-08-05) Author: Silverton Year: 2014, 2011 6 pp. Adopted 2011-08-05. Department of Land Conservation and Development Notice of Adopted Amendment Close

• 9. [Article] Modeling Circulation Dynamics and Submarine Melt in Greenland Fjords

  Meltwater accumulated on the Greenland Ice Sheet drains to glacier beds, discharging into fjords hundreds of meters below sea level. The injection of meltwater at depth generates an upwelling plume that ...

  Citation × Citation Citation Abstract Copy Title: Modeling Circulation Dynamics and Submarine Melt in Greenland Fjords Author: Carroll, Dustin Year: 2017 Meltwater accumulated on the Greenland Ice Sheet drains to glacier beds, discharging into fjords hundreds of meters below sea level. The injection of meltwater at depth generates an upwelling plume that entrains warm ocean water as it rises along the terminus, increasing submarine melt and driving a fjord-scale exchange flow. However, due to sparse ocean-glacier observations, we lack a process understanding of how plumes control fjord circulation and submarine melt. Combining numerical modeling, theory, and observations, this dissertation investigates near-glacier plume dynamics, the influence of glacier depth on plume structure and submarine melt, and the role of fjord-glacier geometry on circulation in tidewater glacier fjords. In Chapter II, I use buoyant plume theory and a nonhydrostatic, three-dimensional ocean–ice model to investigate the sensitivity of plume dynamics to subglacial discharge, turbulent diffusivity, and conduit geometry. Large discharges result in plumes with positive temperature and salinity anomalies in the upper water column. Fjord circulation is sensitive to conduit geometry; distributed subglacial discharge results in a stronger return flow of warm water toward the terminus. In Chapter III, I use buoyant plume theory, initialized with realistic ranges of subglacial discharge, glacier depth, and ocean stratification, to investigate how plume structure and submarine melt vary during summer months in 12 Greenland fjords. Grounding line depth is a primary control on plume-induced submarine melt: deep glaciers produce warm, salty subsurface plumes that undercut termini, and shallow glaciers produce cold, fresh surface-confined plumes that can overcut. Finally, in Chapter IV, I use regional-scale numerical ocean simulations to systematically evaluate how fjord circulation forced by subglacial plumes, tides, and wind stress depends on fjord width, glacier depth, and sill height. Glaciers grounded below sill depth can draw shelf waters over a shallow sill and into fjord basins with seasonal subglacial discharge; this process is independent of external shelf forcing. These results underscore the first-order effect that subglacial discharge and fjord-glacier geometry have in controlling fjord circulation and, thus, ocean heat flux to the ice. This dissertation includes previously published and co-authored material. Title: Modeling Circulation Dynamics and Submarine Melt in Greenland Fjords Author: Carroll, Dustin Year: 2017 Meltwater accumulated on the Greenland Ice Sheet drains to glacier beds, discharging into fjords hundreds of meters below sea level. The injection of meltwater at depth generates an upwelling plume that entrains warm ocean water as it rises along the terminus, increasing submarine melt and driving a fjord-scale exchange flow. However, due to sparse ocean-glacier observations, we lack a process understanding of how plumes control fjord circulation and submarine melt. Combining numerical modeling, theory, and observations, this dissertation investigates near-glacier plume dynamics, the influence of glacier depth on plume structure and submarine melt, and the role of fjord-glacier geometry on circulation in tidewater glacier fjords. In Chapter II, I use buoyant plume theory and a nonhydrostatic, three-dimensional ocean–ice model to investigate the sensitivity of plume dynamics to subglacial discharge, turbulent diffusivity, and conduit geometry. Large discharges result in plumes with positive temperature and salinity anomalies in the upper water column. Fjord circulation is sensitive to conduit geometry; distributed subglacial discharge results in a stronger return flow of warm water toward the terminus. In Chapter III, I use buoyant plume theory, initialized with realistic ranges of subglacial discharge, glacier depth, and ocean stratification, to investigate how plume structure and submarine melt vary during summer months in 12 Greenland fjords. Grounding line depth is a primary control on plume-induced submarine melt: deep glaciers produce warm, salty subsurface plumes that undercut termini, and shallow glaciers produce cold, fresh surface-confined plumes that can overcut. Finally, in Chapter IV, I use regional-scale numerical ocean simulations to systematically evaluate how fjord circulation forced by subglacial plumes, tides, and wind stress depends on fjord width, glacier depth, and sill height. Glaciers grounded below sill depth can draw shelf waters over a shallow sill and into fjord basins with seasonal subglacial discharge; this process is independent of external shelf forcing. These results underscore the first-order effect that subglacial discharge and fjord-glacier geometry have in controlling fjord circulation and, thus, ocean heat flux to the ice. This dissertation includes previously published and co-authored material. Close

• 10. [Article] Superscribing Sustainability: Reformulating China's Contemporary Urbanism

  Within China's post-1980's urban planning discourse, shan-shui, a significance-laden compound character set translatable as `mountain-water' or `landscape', aligned with urban sustainability. The focus ...

  Citation × Citation Citation Abstract Copy Title: Superscribing Sustainability: Reformulating China's Contemporary Urbanism Author: Rodenbiker, Jesse Year: 2013, 2014 Within China's post-1980's urban planning discourse, shan-shui, a significance-laden compound character set translatable as `mountain-water' or `landscape', aligned with urban sustainability. The focus of this genealogical discourse analysis delineates the origins, evolution, interpretation, and application of the term shan-shui within China's contemporary urbanization as a developing urban design paradigm, informed through transnational flows of urban design practices. This work highlights case studies showing this discourse's morphological materializations and analyzes interviews, publications, media, letter exchanges, and urban designs to problematize the use of shan-shui within the discursive processes of urban development and sustainability discourses. The superscription of shan-shui generates a rubric through which Chinese cultural and symbolic elements are (re)formulated in contemporary urban developments and conjoined with sustainable urban design practices facilitating multifaceted ends including efforts towards sustainable urban development, bourgeoning neo-classical urban aesthetics, conceptual bridging of human-nature relations, land-centric capital accumulation, and a vernacular urbanism. Title: Superscribing Sustainability: Reformulating China's Contemporary Urbanism Author: Rodenbiker, Jesse Year: 2013, 2014 Within China's post-1980's urban planning discourse, shan-shui, a significance-laden compound character set translatable as `mountain-water' or `landscape', aligned with urban sustainability. The focus of this genealogical discourse analysis delineates the origins, evolution, interpretation, and application of the term shan-shui within China's contemporary urbanization as a developing urban design paradigm, informed through transnational flows of urban design practices. This work highlights case studies showing this discourse's morphological materializations and analyzes interviews, publications, media, letter exchanges, and urban designs to problematize the use of shan-shui within the discursive processes of urban development and sustainability discourses. The superscription of shan-shui generates a rubric through which Chinese cultural and symbolic elements are (re)formulated in contemporary urban developments and conjoined with sustainable urban design practices facilitating multifaceted ends including efforts towards sustainable urban development, bourgeoning neo-classical urban aesthetics, conceptual bridging of human-nature relations, land-centric capital accumulation, and a vernacular urbanism. Close