Geography Commons^™

“Turn The Faucet”: Right-Wing Hydrosocial Imaginaries Of Irrigation Water In The Western United States, Alexander Reid Ross, Thien-Kim Bui, Alida Cantor

Geography Faculty Publications and Presentations

The second administration of United States President Donald Trump has taken an authoritarian, centralized approach to governance in the United States. Water management is one area in which the president has attempted to show dominance. This research theorizes President Trump’s concept of water in the United States West as a “hydrosocial imaginary” in which the release of water from rivers and reservoirs indicates virility, action, and power, instead of liberal cautiousness and prudence. By ordering the release of two billion gallons of water from California’s Central Valley into the dry Tulare Basin one hundred miles north of Los Angeles for …

Predicting Urban Heat‐Related Illness Across U.S. Climate Regions And Demographics, S. E. Brown, Vivek Shandas

Geography Faculty Publications and Presentations

We still know relatively little about how climate, demographics, built environment, and behaviors interact to drive hospitalizations during extreme heat events (EHEs). To address this paucity in understanding, we draw on extant literature to develop a transdisciplinary discrete event system dynamics (SD) modeling approach to address two research questions about the relationship between EHEs and heat‐related illnesses (HRIs): (a) How will changes in EHE frequencies, intensities, and durations in major Metropolitan Statistical Areas (MSAs) across the contiguous United States (CONUS) Climate Regions drive HRI morbidity across demographic, health‐status, and household groups over the coming decades? and (b) What are the …

A Climatology Of Heat Domes Over North America, Paul C. Loikith, Siiri Bigalke, Graham P. Taylor, Dmitri A. Kalashnikov, Deepti Singh, Amanda Laverty

Geography Faculty Publications and Presentations

The term heat dome in reference to extreme heat events has grown in popularity. While a heat dome definition has recently been added to the Glossary of the American Meteorological Society, a quantitative meteorological definition is currently lacking. Here we present such a definition and use it to develop a novel 85-year climatology of extreme heat and associated mid-tropospheric circulation over mid-latitude North America. Our definition groups extreme heat objects (EHOs), defined daily as spatially contiguous regions where 2-m maximum temperature exceeds the May-September 99th percentile, into two categories: those directly associated with a 500-hPa closed anticyclone and those that …

Effects Of Recurving Western North Pacific Tropical Cyclones On Downstream Ridges Over Pacific-Western North America, Xiaoyu Bai, Dmitri A. Kalashnikov, Paul Loikith, Siiri Bigalke, Alex Mitchell, Mingfang Ting, Lance F. Bosart, Deepti Singh

Geography Faculty Publications and Presentations

Recurving tropical cyclones (TC) in the Western North Pacific can affect the atmospheric circulation over Pacific‐Western North America (PWNA) via interactions with the midlatitude circulation. Using reanalysis and tropical cyclone best‐track data, we examine how recurving TCs that make extratropical transition modulate 500‐hPa ridge characteristics over PWNA during the peak (June‐September) and late (October–December) seasons. TCs recurving at lower latitudes are associated with more intense and poleward‐centered ridges relative to TCs recurving at higher latitudes, and TCs that recurve farther west are associated with relatively westward‐centered ridges. Characteristics of the prevailing midlatitude flow such as its amplitude and positioning relative …

An Assessment Of Historical Planning Processes And Greenspace Distribution (1975–2024): A Case Study Of Portland, Oregon, Usa, Quadri Olatunbosun Taiwo, Vivek Shandas, Damilola Emmanuel Oluyege

Geography Faculty Publications and Presentations

The Portland study examined past planning regulations and greenspace distribution over the period of fifty years, with particular attention given to neighborhood differences between invested and non-invested neighborhoods. This exploratory study examined spatial greenspace using Normalized Difference Vegetation Index (NDVI) imagery. We tested the study hypothesis using the GIS Ordinary Least Squares (OLS) regression test to predict how key sociodemographic characteristics affect the provision of greenspace in non-white disinvested neighborhoods. The key findings suggested a consistent pattern of greenspace inequality, heavily shaped by historically disadvantaged ethnic status. Areas with higher non-white populations may have significant less greenspace (p < 0.001). Although median household income had a minimal negative impact, educational attainment showed a slight positive correlation. We employed multidisciplinary theoretical frameworks such as historical institutionalism, urban political ecology, and environmental justice. The study illustrated how historical decisions may have established path dependencies that are currently perpetuating greenspace inequalities. Policy solutions advocate for integrating restorative justice principles and rigid enforcement of 3-30-300 greenspace equity legislation to offset these long-term disparities.

Post-Wildfire Water Quality And Aquatic Ecosystem Response In The U.S. Pacific Northwest: Science And Monitoring Gaps, Sara Wall, Jana E Compton, Ashley A. Coble, Beth M. Haley, Jiajia Lin, Allison Myers-Pigg, Justin Reale, Katie Wampler, Kevin D. Bladon, Kurt Carpenter, Heejun Chang, Multiple Additional Authors

Geography Faculty Publications and Presentations

An increase in the occurrence of large, high severity wildfires in the western Pacific Northwest (PNW), USA, has created an urgent need for science to better inform forest management and policy decisions to maintain source water quality in the region. The western PNW faces similar challenges to other regions with shifting wildfire regimes and large population centers reliant on surface water from forested catchments. However, the uniquely wet and highly seasonal climate of the western PNW suggests that findings from other, more frequently burned regions may not be directly applicable. To identify science, monitoring, and management gaps and opportunities in …

The Hottest Areas In U.S. Cities Are Losing The Most Greenery, Yunjae Ock, Vivek Shandas

Geography Faculty Publications and Presentations

Due to the significantly increasing impacts of urban heat, cities are seeking to expand tree canopy, parks and other forms of greenery to reduce temperatures. Despite these efforts, few studies have examined the relationship between neighborhood-scale thermal conditions and changes in green spaces. The present study drew on high-resolution, near-surface air temperature measurements in 33 U.S. cities to answer two research questions: (1) to what extent did these cities’ greenery change from 2013 to 2022? and (2) did these study areas have an increase in greenery within neighborhoods exhibiting the hottest air temperatures? Results suggest that 72.7% of cities are …

"We're Going To Tear Up The Caldera So We Can Have An Electric Car": Wrestling With Prospective Lithium Mining In The Oregon Desert, Elizabeth Bartholomew, Alida Cantor, Kate Berry, Noel Vineyard

Geography Faculty Publications and Presentations

Extraction of lithium, a key ingredient for renewable energy transitions, is a land- and water-intensive process. In this study, we use qualitative, place-based research to explore socio-environmental imaginaries surrounding a landscape on the verge of change due to lithium mining. We examine the ways that different actors are wrestling with the costs, benefits, and uncertainties of potential open-pit lithium mining in Oregon’s section of the McDermitt Caldera. In contrast to previous research which has described support for mining amongst those closest to the mine site, we find that in this case, perceptions of mining are characterized by ambivalence, uncertainty, and …

(De)Centralized Water Futures: Key Dimensions Of Infrastructure, Governance, And Operations, Alicia Dailey Cooperman, Jenny Linder Rempel, Ellis Adjei Adams, Alida Cantor, Manuela Muñoz Fuerte, Jeremiah Osborne-Gowey, Nicole J. Wilson, Cassandra L. Workman, Melissa Beresford, Leila M. Harris, Multiple Additional Authors

Geography Faculty Publications and Presentations

Water system centralization and decentralization have variously been promoted as key to achieving household water security and Sustainable Development Goal 6.1. We argue that the lack of specificity with which scholars and practitioners use the terms centralization and decentralization limits our understanding of different water system configurations and their impacts. In this Primer, we provide a framework for thinking about levels of (de)centralization across three linked system dimensions: infrastructure, governance, and operations and maintenance. We encourage those analyzing water systems to characterize (de)centralization with respect to these multiple dimensions, as well as the system's broader political-economic and hydro-climatic contexts. Emphasizing …

Projections Of Lightning‐Ignited Wildfire Risk In The Western United States, Dmitri A. Kalashnikov, John T. Abatzoglou, Frances V. Davenport, Zachary M. Labe, Paul C. Loikith, Danielle Touma, Deepti Singh

Geography Faculty Publications and Presentations

Cloud‐to‐ground (CG) lightning is a major source of summer wildfire ignition in the western United States (WUS). However, future projections of lightning are uncertain since lightning is not directly simulated by most global climate models. To address this issue, we use convolutional neural network (CNN)‐based parameterizations of daily June‐September CG lightning. CNN parameterizations of daily CG lightning occurrence at each grid cell use fields of three thermodynamic variables—ratio of surface Moist Static Energy (MSE) to 500 hPa saturation MSE, 700–500 hPa lapse rate, and 500 hPa relative humidity. Applying these parameterizations to the Community Earth System Model version 2 Large …

La Niña Effects On The Mjo Modulation Of North Pacific Atmospheric Rivers And Associated Western North American Precipitation, L. G. Fernandes, Paul C. Loikith, M. Mora

Geography Faculty Publications and Presentations

We investigate connections between the Madden‐Julian Oscillation (MJO) and North Pacific atmospheric rivers (ARs) and associated precipitation over North America during La Niña (LN) years. Overall, AR frequency is reduced over the northeastern Pacific and western North America in phases 2–5 of the MJO. However, under LN, increased AR activity appears over those regions in phases 4–6 and across the central North Pacific in Phase 3. Distinct effects of LN on the basic state and MJO contribute to the persistence of AR anomalous patterns in phases 3–6. For instance, MJO intensifies in Phase 3 under LN, favoring the coupling between …

The First Thirty Years Of Green Stormwater Infrastructure In Portland, Oregon, Michaela Koucka, Cara Poor, Jordyn Wolfand, Heejun Chang, Vivek Shandas, Adrienne Aiona, Henry Stevens, Tim Kurtz, Svetlana Hedin, Steve Fancher, Joshua Lighthipe, Adam Zucker

Geography Faculty Publications and Presentations

Over the past 30 years, the City of Portland, Oregon, USA, has emerged as a national leader in green stormwater infrastructure (GSI). The initial impetus for implementing sustainable stormwater infrastructure in Portland stemmed from concerns about flooding and water quality in the city’s two major rivers, the Columbia and the Willamette. Heavy rainfall often led to combined sewer overflows, significantly polluting these waterways. A partial solution was the construction of “The Big Pipe” project, a large-scale stormwater containment system designed to filter and regulate overflow. However, Portland has taken a more comprehensive and long-term approach by integrating sustainable stormwater management …

Convergence Research For Sustainable Regional Systems, Heejun Chang, Brian Roe, Murat Erkoc, Josiah Heyman, Katherine Foo, Debankur Sanyal, Debjyoti Banerjee, Richard Rushforth, Jaishri Srinivasan

Geography Faculty Publications and Presentations

Summary:

Convergence research addresses societal and environmental challenges by co-creating knowledge across disciplinary boundaries, often in deep collaboration with extra-academic parties to ensure that the research process is solution-focused, actionable, and just. As part of National Science Foundation (NSF)-funded research projects on sustainable regional systems, we present multiple perspectives on conducting convergence research within the coupled social-ecological-technological systems framework. These projects explicitly engage extra-academic parties to co-design and co-produce knowledge throughout all stages of this participatory research. We introduce the 3 C’s model as a framework that links a research team’s Communication, Collaboration, and Creation decisions to the likely degree …

State Of The Climate In 2024: The Arctic, R. L. Thoman, T. A. Moon, M. L. Druckenmiller, Thomas G. Askjaer, Thomas J. Ballinger, Uma S. Bhatt, Logan T. Berner, Germar H. Bernhard, Siiri Bigalke, Jarle W. Bjerke, Multiple Additional Authors

Geography Faculty Publications and Presentations

The Arctic environment in 2024 continued on a trajectory that has put it in a state far different from that of the twentieth century. Ongoing accumulation of greenhouse gases in the atmosphere continues to quickly warm the Arctic, resulting in rapid changes in the cryosphere that are driving cascading impacts to climate, ecological, and societal systems.

Who Bears The Burden? An Assessment Of Vulnerability And Resilience To Consecutive Disasters In The Portland Metro Region, Idowu Ajibade, Jason Sauer, Matthew Walter, James M. Done, Ming Ge, Elliot Gall, Aswatha Raghunathasami, Paul C. Loikith, Chris Lower, Heejun Chang, Arun Pallathadka, E Mae Sowards

Geography Faculty Publications and Presentations

Climate-related disasters threaten urban areas worldwide, yet gaps remain in understanding how multiple stressors interact to shape resilience. This study examines exposure, vulnerability, and resilience across three consecutive extreme events in the Portland metro area: the September 2020 wildfire-related air pollution, the February 2021 snowstorm, and the June 2021 heatwave. We used geographically weighted regression and Spearman rank correlation analysis to investigate relationships between hazard impacts, the social vulnerability index (SoVI), Baseline Resilience Indicators for Communities (BRIC), and proximity to community-based organizations (CBOs) in 416 census tracts. Our analysis reveals strong spatial correlations between wildfire-related air pollution, winter storm impacts, …

Sunrise At The Salton Sea: Environmental Justice, Land Use Change, And Hydrosocial Dynamics Of Solar Energy Transitions In The Imperial Valley, California, Dustin Mulvaney, James J. A. Blair, Alida Cantor

Geography Faculty Publications and Presentations

California's Imperial Valley, with lithium-rich geothermal brines, extensive flat agricultural fields with abundant desert sunshine, and access to transmission lines, is a leading case to explore interconnected themes around just energy transitions. Despite being the poorest county in California and one of the smallest, Imperial already provides 15% of the state’s solar electricity, and the region as a whole represents on the order of 25% of the state’s electric power capacity. This paper brings to light frictions over solar energy development that have emerged over the history of solar power development in the southern Salton Sea region. It describes the …

Convergence Research For Microplastic Pollution At The Watershed Scale, Heejun Chang, Elise F. Granek, Amanda Gannon, Jordyn M. Wolfand, Janice Brahney

Geography Faculty Publications and Presentations

Microplastics are found in Earth’s atmosphere, lithosphere, hydrosphere, pedosphere, and ecosphere. While there is a growing interest and need to solve this grand challenge in both the academic and policy realms, few have engaged with academics, policymakers, and community partners to co-identify the problem, co-design research, and co-produce knowledge in tackling this issue. Using a convergence research framework, we investigated the perception of microplastic pollution among different end users, delivered educational materials to K-12 teachers and practitioners, and identified key sampling points for assessing environmental microplastic concentrations in the Columbia River Basin, United States. Three community partner workshops identified regional …

Synthesis Of Publications On The Anomalous June 2021 Heat Wave In The Pacific Northwest Of The United States And Canada, Erica Fleishman, David E. Rupp, Paul C. Loikith, Karin A. Bumbaco, Larry W. O'Neill

Geography Faculty Publications and Presentations

We synthesized more than 70 articles, most peer reviewed, that addressed the heat wave that occurred across the Pacific Northwest of the United States and Canada in late June 2021, breaking hundreds of daily and all-time daily maximum temperature records across the region. A persistent, extraordinarily strong ridge of high pressure was a primary driver of the heat wave. Contributing mechanisms were moisture originating in the tropical western Pacific Ocean, high solar radiation, low pressure offshore, large-scale subsidence over land, and unusually dry soils. Climate change contributed to the heat wave’s magnitude by increasing mean temperature, although it is unclear …

Effects Of Climate Change On Stream Temperature And Salmonid Habitats In A Cascades River Basin, Michael Krochta, Kara Anlauf-Dunn, Dave Bugni, Heejun Chang

Geography Faculty Publications and Presentations

Rising stream temperatures pose significant challenges to aquatic ecosystems, particularly for coldwater-adapted organisms like salmonids. This study examines the effects of climate change on stream temperatures and salmonid habitats in the Clackamas River Basin, Oregon, USA. Using spatial stream network models and CMIP6 climate projections under SSP2-4.5 and SSP5-8.5 scenarios, we project mid- (2045-2074) and late-century (2075-2100) stream temperature changes. These projections are then integrated with thermal tolerances and intrinsic habitat metrics to assess future habitat suitability for key species, including steelhead, coho, Chinook, and bull trout. Stream temperature trends from 1991 to 2023 reveal basin-wide warming, with high-elevation tributaries …

Post-Fire Delayed Tree Mortality In Mesic Coniferous Forests Reduces Fire Refugia And Seed Sources, Alec S. Dyer, Sebastian Busby, Cody Evers, Matthew Reilly, Aaron Zuspan, Andres Holz

Geography Faculty Publications and Presentations

Context Ecological functions provided by fire refugia are critical for supporting conifer forest resiliency under increased fire activity across the western United States. The spatial distribution and persistence of fire refugia over time are uncertain as fire-injured trees continue to die over subsequent years post-fire. Objectives We examined how post-fire delayed tree mortality affects the spatial distribution and attributes of fire refugia at patch and landscape scales following high-severity wildfires. Methods To explore changes in fire refugia patch size, isolation, and fragmentation over time, we used high-resolution satellite imagery (3 m pixel size) following high-severity fires in Oregon’s western Cascades …

Disaster Vulnerability Hotspots In The Portland Metro-Region: Converging Indices For Equitable Resilience, Idowu Ajibade, Matthew Walter, Jason Sauer, Aswatha Raghunathasami, James M. Done, Paul Loikith, Chris Lower, Heejun Chang, Arun Pallathadka, Mae E. Sowards, Ming Ge

Geography Faculty Publications and Presentations

As climate-related extreme events intensify across the globe, governments, practitioners, and communities have focused on reducing vulnerability and building resilience. However, debates persist about the validity, differences, and similarities between social vulnerability and resilience indices. This study combines the Social Vulnerability Index (SoVI) (26 indicators) and the Baseline Resilience Indicators for Communities (BRIC) (52 indicators) to assess the Portland Metro region using ACS (2016–2020) and 2020 Census data. Through hotspot analysis, Pearson’s correlation, and linear regression, we identify key drivers as well as areas of convergence and divergence between the two indices. Results show a strong overlap between SoVI and …

Towards An Explicit Understanding Of Network Governance In Urban Forestry Management: A Case Study Of Portland (Or), Usa, Quadri Olatunbosun Taiwo, Vivek Shandas

Geography Faculty Publications and Presentations

As the climate continues to warm, and municipal leaders look for cost-effective and timely approaches to urban sustainability, one increasingly sought-out approach is the use of tree canopy to cool neighborhoods. Despite widespread efforts to expand tree canopy in cities, an overwhelming body of evidence suggests that urban green space is declining across the U.S., yet little is known about the factors that propel these changes. Understanding the institutional and governance systems can help identify the opportunities for slow consistent declines. Using social network analysis (SNA) metrics, we examined stakeholder roles in power structures and decision-making processes within Portland, Oregon’s …

A Case For Change: Flood Risk Management And Green Infrastructure, Heejun Chang, Arun Pallathadka

Geography Faculty Publications and Presentations

With climate change, changing demographics, and the historical legacy of aging infrastructure, many cities are facing challenges in urban flood risk management. We propose potential opportunities and synergies of collaborative urban flood risk management using green infrastructure to achieve social, ecological, and technological benefits.

Towards A Global Understanding Of Tree Mortality, Andres Holz, International Tree Mortality Network

Geography Faculty Publications and Presentations

Rates of tree mortality are increasing globally, with implications for forests and climate. Yet, how and why these trends vary globally remain unknown. Developing a comprehensive assessment of global tree mortality will require systematically integrating data from ground-based long-term forest monitoring with large-scale remote sensing. We surveyed the metadata from 466 865 forest monitoring plots across 89 countries and five continents using questionnaires and discuss the potential to use these to estimate tree mortality trends globally. Our survey shows that the area monitored has increased steadily since 1960, but we also identify many regions with limited ground-based information on tree …

Patagonia's Late Holocene Lake Sediments Reveal No Major Black Carbon Sources For Antarctica, Sandra O. Brugger, David B. Mcwethy, Nathan Chellman, Oliver Heiri, Kyla Sara Zaret, Joseph R. Mcconnell, Andres Holz, Joseph R. Mcconnell

Geography Faculty Publications and Presentations

Black carbon from biomass and fossil fuel burning is an important aerosol in the climate system. Understanding its historical variation is crucial to constrain current anthropogenic and wildfire impacts on the atmosphere. Patagonia was proposed previously as a major source region for the late 13th century black carbon increase observed in an ice core from the northern Antarctic Peninsula but not in continental Antarctic ice cores. Here, we reconstruct regional black carbon trends using high-resolution measurements of refractory black carbon (rBC) in two Patagonian lake-sediment cores spanning the last two millennia and compare the results with other records of fire …

Pumped Storage Hydropower In The United States: Emerging Importance, Environmental And Social Impacts, And Critical Considerations, Surabhi Karambelkar, Alida Cantor, Thien-Kim Bui, Bethani Turley, Maryalice Fischer, Shannon Ames

Geography Faculty Publications and Presentations

Pumped storage hydropower is a widely used, long-duration energy storage system that sits squarely at the water-energy nexus. Bold decarbonization goals have propelled a rapid resurgence of interest in pumped storage hydropower in the US, given its ability to provide bulk energy storage, manage grid reliability, and support increasing integration of variable renewable energy sources. Drawing on published research from both technical and social science perspectives, this paper provides an overview of pumped storage hydropower technology, the project development pipeline, potential social and environmental impacts, including a comparison of open-loop and closed-loop design configurations, and critical considerations for project development. …

Predicting Post-Wildfire Stream Temperature And Turbidity: A Machine Learning Approach In Western Us Watersheds, Junjie Chen, Heejun Chang

Geography Faculty Publications and Presentations

Wildfires significantly impact water quality in the Western United States, posing challenges for water resource management. However, limited research quantifies post-wildfire stream temperature and turbidity changes across diverse climatic zones. This study addresses this gap by using Random Forest (RF) and Support Vector Regression (SVR) models to predict post-wildfire stream temperature and turbidity based on climate, streamflow, and fire data from the Clackamas and Russian River Watersheds. We selected Random Forest (RF) and Support Vector Regression (SVR) because they handle non-linear, high-dimensional data, balance accuracy with efficiency, and capture complex post-wildfire stream temperature and turbidity dynamics with minimal assumptions. The …

Explaining The 2022 Record Low Great Salt Lake Volume, Siiri Bigalke, Paul C. Loikith, Nicholas Siler

Geography Faculty Publications and Presentations

The Great Salt Lake reached the lowest water volume in its entire 170+ year record in 2022. To explain this record low we develop and apply a lake mass‐balance model and perform four simulations: one where all input and output variables are fixed to their mid‐20th century average resulting in an equilibrium lake volume, and three others where one of the input variables (precipitation or streamflow) or the output variable (evaporation) follows observations while the other two are fixed to their mid‐20th century average. Results show anomalously low streamflow accounting for the largest proportion of the lake volume departure from …

Unseen Connections: A Storymap Exploring Case Studies In Water-Energy Transitions And Environmental Justice, Alida Cantor, Elizabeth Bartholomew, Kate Berry, James Blair, Dustin Mulvaney, Nancee Hunter

Geography Faculty Publications and Presentations

Climate change is one of the most important challenges in the world today. Communities and decision makers at many levels, from local to international, are working to ensure that energy, water, and other societal infrastructures can transition and adapt to address climate change (IPCC, 2023). One major mitigation strategy involves the decarbonization of energy systems (Rockström et al. 2017). Despite wide recognition of the need to decarbonize globally, renewable energy infrastructures and technologies are often locally controversial, involving claims of environmental injustice and disputes over land and water (Cantor, Turley, and Maxfield 2023; Jerez, Garcés, and Torres 2021; Turley et …

Thermal Regimes Of Beaver-Impacted Stream Reaches In The Tualatin River Basin, Oregon, United States, Miles Mayer, Heejun Chang

Geography Faculty Publications and Presentations

As beavers are increasingly used in stream restoration, interest in their potential to mitigate stream degradation has grown. However, the impacts of beaver dams on stream temperature remain inconsistent across studies, often due to differences in spatial scale and methodology. We investigated summer thermal regimes at multiple spatial scales in three beaver-impacted streams within the Tualatin River Basin, Oregon, using fiber-optic distributed temperature sensing. Substantial variability in thermal regimes was observed among the three stream reaches and around individual beaver dams within each reach. This variability was primarily influenced by geomorphic changes in stream depth associated with beaver dams and …