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• 1. [Article] Controls on the Kinematics of Slow-moving Landslides from Satellite Radar Interferometry and Mechanical Modeling

  Landslides display a wide variety of behaviors ranging from slow persistent motion to rapid acceleration and catastrophic failure. Given the variety of possible behaviors, improvements to our understanding ...

  Citation × Citation Citation Abstract Copy Title: Controls on the Kinematics of Slow-moving Landslides from Satellite Radar Interferometry and Mechanical Modeling Author: Handwerger, Alexander Year: 2015 Landslides display a wide variety of behaviors ranging from slow persistent motion to rapid acceleration and catastrophic failure. Given the variety of possible behaviors, improvements to our understanding of landslide mechanics are critical for accurate predictions of landslide dynamics. Recent advances in remote sensing techniques, like satellite radar interferometry (InSAR), now enable high-resolution spatial and temporal measurements that provide insight into the mechanisms that control landslide behavior. In this dissertation, I use InSAR and high-resolution topographic data to identify 50 slow-moving landslides in the Northern California Coast Ranges and monitor their kinematics over 4 years. These landslides have similar mechanical properties and are subject to the same external forcings, which allows me to explore geometrical controls on kinematics. Each landslide displays distinct kinematic zones with different mean velocities that remain spatially fixed. Because these deformation patterns are sensitive to subsurface geometry, I employ a mathematical model to infer landslide thickness and find that these landslides exhibit a highly variable thickness and an irregular basal sliding surface. Time series analysis reveals that each landslide displays well-defined seasonal velocity changes with a periodicity of ∼ 1 year. These velocity variations are driven by precipitation- induced changes in pore-water pressure that lag the onset of rainfall by up to 40 days. Despite significant variations in geometry, I find no systematic differences in seasonal landslide behavior. To further explore how stress perturbations control landslide motion, I develop a mechanical model that reproduces both the displacement patterns observed at slow-moving landslides and the acceleration towards failure exhibited by catastrophic events. I find that catastrophic failure can only occur when the slip surface is characterized by rate-weakening friction and its spatial dimensions exceed a critical nucleation length that is shorter for higher effective stresses. These model simulations support my conclusions from the remote sensing analysis but also provide insight into the long-term evolution of landslides. This dissertation includes both previously published and unpublished co- authored material. Title: Controls on the Kinematics of Slow-moving Landslides from Satellite Radar Interferometry and Mechanical Modeling Author: Handwerger, Alexander Year: 2015 Landslides display a wide variety of behaviors ranging from slow persistent motion to rapid acceleration and catastrophic failure. Given the variety of possible behaviors, improvements to our understanding of landslide mechanics are critical for accurate predictions of landslide dynamics. Recent advances in remote sensing techniques, like satellite radar interferometry (InSAR), now enable high-resolution spatial and temporal measurements that provide insight into the mechanisms that control landslide behavior. In this dissertation, I use InSAR and high-resolution topographic data to identify 50 slow-moving landslides in the Northern California Coast Ranges and monitor their kinematics over 4 years. These landslides have similar mechanical properties and are subject to the same external forcings, which allows me to explore geometrical controls on kinematics. Each landslide displays distinct kinematic zones with different mean velocities that remain spatially fixed. Because these deformation patterns are sensitive to subsurface geometry, I employ a mathematical model to infer landslide thickness and find that these landslides exhibit a highly variable thickness and an irregular basal sliding surface. Time series analysis reveals that each landslide displays well-defined seasonal velocity changes with a periodicity of ∼ 1 year. These velocity variations are driven by precipitation- induced changes in pore-water pressure that lag the onset of rainfall by up to 40 days. Despite significant variations in geometry, I find no systematic differences in seasonal landslide behavior. To further explore how stress perturbations control landslide motion, I develop a mechanical model that reproduces both the displacement patterns observed at slow-moving landslides and the acceleration towards failure exhibited by catastrophic events. I find that catastrophic failure can only occur when the slip surface is characterized by rate-weakening friction and its spatial dimensions exceed a critical nucleation length that is shorter for higher effective stresses. These model simulations support my conclusions from the remote sensing analysis but also provide insight into the long-term evolution of landslides. This dissertation includes both previously published and unpublished co- authored material. Close

• 2. [Article] Functionalized Nano-structured Silicas for Trace Collection from Natural Waters

  Throughout this body of work, three classes of sorbent materials were created and optimized, each designed to selectively capture organics or desired metals from natural water sources. These target species ...

  Citation × Citation Citation Abstract Copy Title: Functionalized Nano-structured Silicas for Trace Collection from Natural Waters Author: Nell, Kara Year: 2016 Throughout this body of work, three classes of sorbent materials were created and optimized, each designed to selectively capture organics or desired metals from natural water sources. These target species included toxic heavy metals, uranium, rare earths, and simple organics, such as benzene. Each class of sorbent materials is functionalized nanostructured silicas, created by the development of several functionalization methods: utilizing thiol-ene click chemistry, aromatic interactions, and the formation of inclusion complexes. Thiol-ene click surface modification gave rise to sorbent materials with impressive affinities for both soft metals, such as gold, and harder metals, such as uranium and rare earth elements. Applications of these materials for aqueous mining of uranium and rare earth elements from various natural water sources are presented. Two classes of materials based on supramolecular functionalization methods were prepared. In the first class, aromatic interactions allowed for surface functionalization with thiol containing aryl ligands. These materials proved to have an excellent affinity for heavy metals from natural waters, and hold promise for regenerable nanostructured silica sorbents. The second class of materials utilizes the ability of β-cyclodextins to form inclusion complexes with small molecule organics, such as benzene. The formation of inclusion complexes drove both surface functionalization and the capture of small molecule organics from aqueous solutions. This work serves to inspire the development of novel functionalized nanostructured sorbents for trace collection of toxic organics from aqueous streams. These supramolecular methods for surface medication can be expanded to nanomaterials at large. This dissertation includes both previously published/unpublished and co-authored material. Title: Functionalized Nano-structured Silicas for Trace Collection from Natural Waters Author: Nell, Kara Year: 2016 Throughout this body of work, three classes of sorbent materials were created and optimized, each designed to selectively capture organics or desired metals from natural water sources. These target species included toxic heavy metals, uranium, rare earths, and simple organics, such as benzene. Each class of sorbent materials is functionalized nanostructured silicas, created by the development of several functionalization methods: utilizing thiol-ene click chemistry, aromatic interactions, and the formation of inclusion complexes. Thiol-ene click surface modification gave rise to sorbent materials with impressive affinities for both soft metals, such as gold, and harder metals, such as uranium and rare earth elements. Applications of these materials for aqueous mining of uranium and rare earth elements from various natural water sources are presented. Two classes of materials based on supramolecular functionalization methods were prepared. In the first class, aromatic interactions allowed for surface functionalization with thiol containing aryl ligands. These materials proved to have an excellent affinity for heavy metals from natural waters, and hold promise for regenerable nanostructured silica sorbents. The second class of materials utilizes the ability of β-cyclodextins to form inclusion complexes with small molecule organics, such as benzene. The formation of inclusion complexes drove both surface functionalization and the capture of small molecule organics from aqueous solutions. This work serves to inspire the development of novel functionalized nanostructured sorbents for trace collection of toxic organics from aqueous streams. These supramolecular methods for surface medication can be expanded to nanomaterials at large. This dissertation includes both previously published/unpublished and co-authored material. Close

• 3. [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

• 4. [Article] Iceberg Properties and Distributions in Three Greenlandic Fjords Using Satellite Imagery

  Icebergs calved from tidewater glaciers represent significant portions of freshwater flux from the Greenland Ice Sheet to the ocean. Using satellite data sets we quantify properties and distributions of ...

  Citation × Citation Citation Abstract Copy Title: Iceberg Properties and Distributions in Three Greenlandic Fjords Using Satellite Imagery Author: Sulak, Daniel Year: 2016 Icebergs calved from tidewater glaciers represent significant portions of freshwater flux from the Greenland Ice Sheet to the ocean. Using satellite data sets we quantify properties and distributions of icebergs in three fjords with varied properties: Sermilk, Rink Isbræ, and Kangerdlugssûp Sermerssua. Total iceberg volumes in summer in the three fjords average 6.43, 1.69, and 0.19 km^3, respectively, and we calculate cumulative submerged surface areas of iceberg faces to be 213, 55.2, and 7.57 km^2, respectively. We calculate a freshwater flux from iceberg melt of 0.009 – 0.083 m^3 d^-1 in Sermilik Fjord, suggesting a strong potential of iceberg melt water to influence water properties. Properties of icebergs and size distributions are influenced by calving style and grounding line depths of parent glaciers. Variations are represented in the coefficients of generalized Pareto distributions which best describe size distributions in the fjords. Title: Iceberg Properties and Distributions in Three Greenlandic Fjords Using Satellite Imagery Author: Sulak, Daniel Year: 2016 Icebergs calved from tidewater glaciers represent significant portions of freshwater flux from the Greenland Ice Sheet to the ocean. Using satellite data sets we quantify properties and distributions of icebergs in three fjords with varied properties: Sermilk, Rink Isbræ, and Kangerdlugssûp Sermerssua. Total iceberg volumes in summer in the three fjords average 6.43, 1.69, and 0.19 km^3, respectively, and we calculate cumulative submerged surface areas of iceberg faces to be 213, 55.2, and 7.57 km^2, respectively. We calculate a freshwater flux from iceberg melt of 0.009 – 0.083 m^3 d^-1 in Sermilik Fjord, suggesting a strong potential of iceberg melt water to influence water properties. Properties of icebergs and size distributions are influenced by calving style and grounding line depths of parent glaciers. Variations are represented in the coefficients of generalized Pareto distributions which best describe size distributions in the fjords. Close

• 5. [Article] Riparian Buffers: The Lack of Buffer Protection Policies and Recommendations to Expand Protection

  22 pages

  Citation × Citation Citation Abstract Copy Title: Riparian Buffers: The Lack of Buffer Protection Policies and Recommendations to Expand Protection Author: Merrill, Maximilian Year: 2016 22 pages Title: Riparian Buffers: The Lack of Buffer Protection Policies and Recommendations to Expand Protection Author: Merrill, Maximilian Year: 2016 22 pages Close

• 6. [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

• 7. [Article] City of Gold Hill Surface Water Management Program

  70 pages

  Citation × Citation Citation Abstract Copy Title: City of Gold Hill Surface Water Management Program Author: McFerson, KC, Page, Alex, Varien, Michael, Hanson, Casey, Harbage, Rebecca Year: 2014, 2013 70 pages Title: City of Gold Hill Surface Water Management Program Author: McFerson, KC, Page, Alex, Varien, Michael, Hanson, Casey, Harbage, Rebecca Year: 2014, 2013 70 pages Close

• 8. [Article] City of Oakridge Surface Water Management Program

  80 pages

  Citation × Citation Citation Abstract Copy Title: City of Oakridge Surface Water Management Program Author: McFerson, KC, Page, Alex, Varien, Michael, Protzman, Ben, Forsell, Erik, Ostrove, Geoff, Harbage, Rebecca, Hanson, Casey Year: 2014, 2013 80 pages Title: City of Oakridge Surface Water Management Program Author: McFerson, KC, Page, Alex, Varien, Michael, Protzman, Ben, Forsell, Erik, Ostrove, Geoff, Harbage, Rebecca, Hanson, Casey Year: 2014, 2013 80 pages Close

• 9. [Article] Physical Oceanography, Larval Dispersal, and Settlement Across Nearshore Fronts

  The larvae of coastal species interact with nearshore currents that are complex and can alter dispersal. I investigated two sites in southern Oregon with different nearshore hydrodynamics: the first site, ...

  Citation × Citation Citation Abstract Copy Title: Physical Oceanography, Larval Dispersal, and Settlement Across Nearshore Fronts Author: Jarvis, Marley Year: 2015 The larvae of coastal species interact with nearshore currents that are complex and can alter dispersal. I investigated two sites in southern Oregon with different nearshore hydrodynamics: the first site, Sunset Bay, is a small cove with a topographic front that extends across the mouth during upwelling-favorable winds. Using holey sock drogues at 1.5 m and 5.5 m depths and surface drifters at 10 cm depth, I found that, when the front was present, water at 1.5 m was retained within the bay whereas water was exchanged across the front at a depth of 5.5 m. Surface drifters indicated a surface convergence. Surface plankton tows on either side and within the frontal convergence (a shore-parallel foam line) found significantly higher concentrations of barnacle cyprids, crab megalopae and zoea, polychaete larvae, platyhelminthes juveniles, isopods, amphipods, harpacticoid copepods, and fish eggs. Crustacean nauplii (barnacle, euphausiid, and copepod) and calanoid copepods were not concentrated in the convergence, and when the front and foam line were absent, no taxa were concentrated. Plankton tows taken within the foam line as it dissipated shoreward during a wind-reversal event found that concentrations of cyprids, megalopae, and gastropod veligers remained high as the foam line moved, suggesting that it acts as a moving convergence propagating competent larvae shoreward. I measured settlement of two taxa at Sunset Bay and Shore Acres, an open-coast site <2 km away. Barnacle settlement measured every other day from June-September 2013 was significantly cross-correlated with the maximum daily tidal height at lags of -2 days at Sunset Bay and +2 and +4 days at Shore Acres. Settlement was also significantly negatively cross-correlated with wave height at a lag of -4 days at Sunset Bay. Coralline algae settlement measured during eight 48-hr periods in July-August 2013 was significantly negatively correlated with wave height (n = 8, R2 = 0.76, P = 0.0049) at Shore Acres but not at Sunset Bay. Despite the close proximity of the Sunset Bay and Shore Acres sites, settlement patterns differed between taxa, suggesting that differences in nearshore hydrodynamics might affect the supply of water and larvae to shore. This dissertation includes unpublished co-authored material. Title: Physical Oceanography, Larval Dispersal, and Settlement Across Nearshore Fronts Author: Jarvis, Marley Year: 2015 The larvae of coastal species interact with nearshore currents that are complex and can alter dispersal. I investigated two sites in southern Oregon with different nearshore hydrodynamics: the first site, Sunset Bay, is a small cove with a topographic front that extends across the mouth during upwelling-favorable winds. Using holey sock drogues at 1.5 m and 5.5 m depths and surface drifters at 10 cm depth, I found that, when the front was present, water at 1.5 m was retained within the bay whereas water was exchanged across the front at a depth of 5.5 m. Surface drifters indicated a surface convergence. Surface plankton tows on either side and within the frontal convergence (a shore-parallel foam line) found significantly higher concentrations of barnacle cyprids, crab megalopae and zoea, polychaete larvae, platyhelminthes juveniles, isopods, amphipods, harpacticoid copepods, and fish eggs. Crustacean nauplii (barnacle, euphausiid, and copepod) and calanoid copepods were not concentrated in the convergence, and when the front and foam line were absent, no taxa were concentrated. Plankton tows taken within the foam line as it dissipated shoreward during a wind-reversal event found that concentrations of cyprids, megalopae, and gastropod veligers remained high as the foam line moved, suggesting that it acts as a moving convergence propagating competent larvae shoreward. I measured settlement of two taxa at Sunset Bay and Shore Acres, an open-coast site <2 km away. Barnacle settlement measured every other day from June-September 2013 was significantly cross-correlated with the maximum daily tidal height at lags of -2 days at Sunset Bay and +2 and +4 days at Shore Acres. Settlement was also significantly negatively cross-correlated with wave height at a lag of -4 days at Sunset Bay. Coralline algae settlement measured during eight 48-hr periods in July-August 2013 was significantly negatively correlated with wave height (n = 8, R2 = 0.76, P = 0.0049) at Shore Acres but not at Sunset Bay. Despite the close proximity of the Sunset Bay and Shore Acres sites, settlement patterns differed between taxa, suggesting that differences in nearshore hydrodynamics might affect the supply of water and larvae to shore. This dissertation includes unpublished co-authored material. Close

• 10. [Article] Dollars and Sense: An Evaluation of Ecosystem Services Provided by Spencer’s Butte Park

  66 pages

  Citation × Citation Citation Abstract Copy Title: Dollars and Sense: An Evaluation of Ecosystem Services Provided by Spencer’s Butte Park Author: Forsell, Erik Year: 2014 66 pages Title: Dollars and Sense: An Evaluation of Ecosystem Services Provided by Spencer’s Butte Park Author: Forsell, Erik Year: 2014 66 pages Close