Geography Commons^™

Subseasonal Clustering Of Atmospheric Rivers Over The Western United States, Emily Slinskey, Paul Loikith, Naomi Goldenson, Jesse Norris, Jesse Hall

Geography Faculty Publications and Presentations

The serial occurrence of atmospheric rivers (ARs) along the US West Coast can lead to prolonged and exacerbated hydrologic impacts, threatening flood-control and water-supply infrastructure due to soil saturation and diminished recovery time between storms. Here a statistical approach for quantifying subseasonal temporal clustering among extreme events is applied to a 41-year (1979–2019) wintertime AR catalog across the western United States (US). Observed AR occurrence, compared against a randomly distributed AR timeseries with the same average event density, reveals temporal clustering at a greater-than-random rate across the western US with a distinct geographical pattern. Compared to the Pacific Northwest, significant …

Disappeared Streams And Flood Risk In Atlanta, Georgia, Baltimore, Maryland, Phoenix, Arizona, And Portland, Oregon, Gregory Chrisopher Post

Dissertations and Theses

Many urban streams have been moved, culverted, buried, or "disappeared" as urban infrastructure was constructed. This loss of natural streams provided land for urban development, but as climate change increases the frequency and severity of extreme weather events, these disappeared stream areas could threaten homes and other infrastructure with increased flood risk. This study developed spatial data layers to identify many of these lost streams for Atlanta, Georgia, Baltimore, Maryland, and Phoenix Arizona, using historical maps to find streams previously visible that disappeared by the present day. This process used the oldest available georeferenced maps from the United States Geological …

Structure-From-Motion Derived Snow Cover In Burned Forests Of The Western Oregon Cascades, Siobhan Ciafone

Dissertations and Theses

Forest fire occurrence in the western US has increased rapidly since the 1980s, and most western US fires occur in the seasonal snow zone. Burned forests influence snow accumulation and melt patterns for years following fire, and understanding drivers of variability in snow cover across a burned landscape at the basin-scale is necessary for accurate hazard prediction and water resource forecasting. Basin-scale surveys of snowpack are possible with remote sensing, but accurate sensing methods such as Light Detection and Ranging (LiDAR) are often cost-prohibitive. In the last decade, structure-from-motion (SfM), an optical remote sensing technique, has emerged as an affordable …

Lightning-Ignited Wildfires In The Western United States: Ignition Precipitation And Associated Environmental Conditions, Dmitri Alexander Kalashnikov, John T. Abatzoglou, Paul Loikith, Nicholas J. Nauslar, Yianna Sotirios Bekris, Deepti Singh

Geography Faculty Publications and Presentations

Cloud-to-ground lightning with minimal rainfall (“dry” lightning) is a major wildfire ignition source in the western United States (WUS). Although dry lightning is commonly defined as occurring with <2.5 mm of daily-accumulated precipitation, a rigorous quantification of precipitation amounts concurrent with lightning-ignited wildfires (LIWs) is lacking. We combine wildfire, lightning and precipitation data sets to quantify these ignition precipitation amounts across ecoprovinces of the WUS. The median precipitation for all LIWs is 2.8 mm but varies with vegetation and fire characteristics. “Holdover” fires not detected until 2–5 days following ignition occur with significantly higher precipitation (5.1 mm) compared to fires detected promptly after ignition (2.5 mm), and with cooler and wetter environmental conditions. Further, there is substantial variation in precipitation associated with promptly-detected (1.7–4.6 mm) and holdover (3.0–7.7 mm) fires across ecoprovinces. Consequently, the widely-used 2.5 mm threshold does not fully capture lightning ignition risk and incorporating ecoprovince-specific precipitation amounts would better inform WUS wildfire prediction and management.

Canary In The Forest?—Tree Mortality And Canopy Dieback Of Western Redcedar Linked To Drier And Warmer Summers, Robert A. Andrus, L. R. Peach, A. R. Cinquini, Joseph Hulbert, J. T. Yusi, Andres Holz, M. Fischer, Kevan B. Moffett, Multiple Additional Authors

Geography Faculty Publications and Presentations

Aim: Forest dieback is increasing from unfavourable climate conditions. Western redcedar (WRC)—a culturally, ecologically and economically important species—has recently experienced anomalously high mortality rates and partial canopy dieback. We investigated how WRC tree growth and dieback responded to climate variability and drought using tree-ring methods. Location: Pacific Northwest, USA. Taxon: Western redcedar (Thuja plicata). Methods: We collected tree cores from three tree health status groups (no canopy dieback, partial canopy dieback, and dead trees) at 11 sites in coastal (maritime climate) and interior (continental climate) WRC populations. From growth rates, we computed four growth indices that assessed the resilience to …

Water Quality Land Cover Change And Water Quality In Wetlands At The City Of Gresham, Or, Evelyn Barajas, Michael Gonzalez

altREU Projects

The City of Gresham, Oregon has implemented constructed wetlands around the area as an attempt to collect, filter, and purify water from different sources such as rain, agricultural waste, and domestic waste. We focused our research on three different facilities: Columbia Slough Water Quality Facility (CSWQF), Fairview Creek Water Quality Facility, and Brookside Water Quality Facility. For each of these, we conducted tests and looked at the concentration levels for nitrogen and phosphorus nutrients such as NH3-N (ammonium), NO3-N (nitrate), TKN (total Kjeldahl nitrogen), O-PO4 (phosphate), and Total P (total phosphorus), as well as heavy metals like Total Cu (total …

Wildfire Risk Governance From The Bottom Up: Linking Local Planning Processes In Fragmented Landscapes, Matthew Hamilton, Max Nielsen-Pincus, Cody Evers

Environmental Science and Management Faculty Publications and Presentations

The growing scale of natural hazards highlights the need for models of governance capable of addressing risk across administrative boundaries. However, risk governance systems are often fragmented, decentralized, and sustained by informal linkages among local-level risk mitigation planning processes. Improving resilience to the effects of environmental change requires a better understanding of factors that contribute to these linkages. Using data on the patterns of participation of 10,199 individual stakeholders in 837 community wildfire protection plans (CWPPs) within the western U.S., we document the emergence of a locally clustered but spatially extensive wildfire risk governance network. Our evaluation of factors that …

Urban Sustainability Implementation And Indicators In The United States: A Systematic Review, Heejun Chang, Arun Pallathadka, Idowu Ajibade

Geography Faculty Publications and Presentations

Urban sustainability is the goal of many cities in the world, yet very few have achieved a level of sustainability that goes beyond the most basic environmental objectives. The practice and assessment of sustainability implementation are greatly compounded by lack of funding, technical know-how, political will, and the power disparity between dominant institutions and marginalized communities. This systematic analysis of urban sustainability literature involved the review of 241 studies published between 2010 and 2022. We critically examined current debates and challenges in urban sustainability, identifying gaps and opportunities and providing recommendations for creating equitable, just, and sustainable urban futures. We …

Quantifying Damages To Soil Health And Emissions From Land Development In The State Of Illinois (Usa), Elena A. Mikhailova, Hamdi A. Zurqani, Zhenbang Hao, Mark A. Schlautman, Gregory C. Post, George B. Shepherd, Christopher C. Post, Renee M. Dixon

Geography Faculty Publications and Presentations

The concept of soil health is increasingly being used as an indicator for sustainable soil management and even includes legislative actions. Current applications of soil health often lack geospatial and monetary analyses of damages (e.g., land development), which can degrade soil health through loss of carbon (C) and productive soils. This study aims to evaluate the damages to soil health (e.g., soil C, the primary soil health indicator) attributed to land developments within the state of Illinois (IL) in the United States of America (USA). All land developments in IL can be associated with damages to soil health, with 13,361.0 …

Spatial Analysis Of Streamflow Trends In Burned Watersheds Across The Western Contiguous United States, Heejun Chang, Will B. Long

Geography Faculty Publications and Presentations

Despite increasing magnitude and frequency of wildfire, understanding hydrological processes contributing to changes in streamflow is not well examined for the entire western contiguous United States (WCONUS). This study provides insight into whether considering spatially varying watershed characteristics, including burn severity patterns, can better explain streamflow trends at broad spatial and temporal scales. Standard geographically weighted regression (GWR) and multi-scalar (MS) GWR were benchmarked against ordinary least squares (OLS) regression to determine if spatially varying coefficients could better explain spatially varying patterns and processes of peak flow, low flow, center timing of flow, and flashiness trends in burned watersheds. In …

Heat Mapping Crime: A Data-Driven Approach To Policing In New York, Beruktawit Gebreamlak, Daniel Ochoa

altREU Projects

In the aftermath of the COVID-19 pandemic, New York City has seen a surge in criminal activities. In 2023, major crime continues to be higher compared to pre-pandemic levels. Although progress is being made to reduce the number of murders and robberies, law enforcement is continuing to struggle with increases in felony assaults and car thefts. Our project serves to benefit members of the community and law enforcement alike. We created a heat map, which is a visual representation of data that uses colors to represent different values. In the context of crime mapping, our heat map is used to …

The Impact Of Climate Change On Selected Pnw Watersheds Through The Lens Of Western Red Cedar Habitat, Jordan T. Hamann

Dissertations and Theses

Climate change is a real phenomenon that is exacerbating existing natural processes and developing into a new normal for the planet. This change may be devastating for Pacific Northwest populations of Western Red Cedar (WRC) west of the Cascade Mountain range in the states of Oregon and Washington. WRC is a valuable tree species for reasons both economic and cultural. Dieback among WRC is following an accelerating trend. Since dieback is usually followed by tree mortality, understanding its causes and distribution is beneficial to the overall success of the species going into the future.

Through the use of ESRI's ArcGIS …

Enhancing The Definitions Of Climate-Change Loss And Damage Based On Land Conversion In Florida, U.S.A., Elena A. Mikhailova, Zhenbang Hao, Hamdi A. Zurqani, Mark A. Schlautman, Gregory C. Post, George B. Shepherd, Sarah J. Kolarik

Geography Faculty Publications and Presentations

Loss and damage (L&D) from climate change result from past and current greenhouse gas (GHG) emissions. Current definitions of L&D exclude GHG emissions even though they represent L&D to human beings and the environment. This study’s objective was to identify and quantify the L&D from GHG emissions associated with land developments using the state of Florida (FL) in the United States of America (USA) as a case study. All land developments in FL caused various L&D (20,249.6 km2, midpoint 3.0 1011 of total soil carbon (TSC) losses with midpoint $50.3B (where B = billion = 109, USD) in social costs …

What Explains Spatial Cariations Of Covid-19 Vaccine Hesitancy?: A Social-Ecological-Technological Systems Approach, Arun Pallathadka, Heejun Chang, Daikwon Han

Geography Faculty Publications and Presentations

While COVID-19 vaccines have been available since December 2020 and efforts have been made to vaccinate the maximum population, a large number of people are continuing to be hesitant, prolonging the pandemic in the US. While most previous studies investigated social, economic, and demographic variables that are associated with COVID-19 vaccine hesitancy, we added ecological and technological variables to better understand the spatial variations of vaccine rates in the contiguous United States using spatial regression and geographically weighted regression (GWR) models. We aim to identify spatially varying social, ecological, and technological factors that are associated with COVID-19 vaccination rates, which …

An Integrated Analysis Of Urban Sustainability In Portland: Issues, Indicators, Stakeholders, And Geospatial Assessment, Arun Kumar Pallathadka

Dissertations and Theses

This dissertation presents three individual studies that collectively explore the concept of urban sustainability. The research is grounded in the recognition that many cities worldwide are striving to achieve sustainable development, yet existing sustainability frameworks often lack comprehensive definition and consideration. Moreover, the existing sustainability frameworks and methods are often not clearly structured to allow for their replication and adaptation to meet the unique needs of diverse local settings. To address this gap, the dissertation utilizes the Social-Ecological-Technological Framework, with particular emphasis on equity, to investigate key issues in urban sustainability, such as indicators, stakeholder engagement, tradeoffs, and assessment. The …

The Role Of The Armed Forces Of The Philippines (Afp) In Disaster Response And Adaptation Strategies To Climatic Disasters In Manila, Edmundo Nicolas Jr.

Geography Masters Research Papers

This study described the roles of the Armed Forces of the Philippines (AFP) in Disaster Risk Reduction Management (DRRM) in Metro Manila and how climate-induced hazards impact the role of the military. It used a qualitative approach, which involved semi- structured interviews among AFP officers and barangay leaders with expertise and experience in DRRM and an analysis of selected policy documents and military doctrine. These methods revealed that: (1) the military acts as a political first-aid, since they are the first responders – thus, the face of the local government – in climactic disasters during peacetime; (2) the military is …

Climate Change And Coastal Megacities: Adapting Through Mobility, Susan S. Ekoh, Lemir Teron, Idowu Ajibade

Geography Faculty Publications and Presentations

Climate change poses threats to individuals, communities, and cities globally. Global conversations and scholarly debates have explored ways people adapt to the impacts of climate change including through migration and relocation. This study uses Lagos, Nigeria as a case study to examine the relationship between flooding events, migration intentions as a preferred adaptation, and the destination choices for affected residents. The study draws on a mixed-methods approach which involved a survey of 352 residents and semi-structured interviews with 21 residents. We use a capability approach to analyze mobility decisions following major or repetitive flood events. We found that the majority …

Reduced Fire Severity Offers Near-Term Buffer To Climate-Driven Declines In Conifer Resilience Across The Western United States, Kimberly T. Davis, Marcos D. Robles, Kerry B. Kemp, Teresa Chapman, Philip E. Higuera, Kerry L. Metlen, Jamie L. Peeler, Andres Holz, Multiple Additional Authors

Geography Faculty Publications and Presentations

Increasing fire severity and warmer, drier postfire conditions are making forests in the western United States (West) vulnerable to ecological transformation. Yet, the relative importance of and interactions between these drivers of forest change remain unresolved, particularly over upcoming decades. Here, we assess how the interactive impacts of changing climate and wildfire activity influenced conifer regeneration after 334 wildfires, using a dataset of postfire conifer regeneration from 10,230 field plots. Our findings highlight declining regeneration capacity across the West over the past four decades for the eight dominant conifer species studied. Postfire regeneration is sensitive to high-severity fire, which limits …

Short Warm Distribution Tails Accelerate The Increase Of Humid-Heat Extremes Under Global Warming, Paul Loikith, Yianna Sotirios Bekris, J. D. Neelin

Geography Faculty Publications and Presentations

Humid-heat extremes threaten human health and are increasing in frequency with global warming, so elucidating factors affecting their rate of change is critical. We investigate the role of wet-bulb temperature (TW) frequency distribution tail shape on the rate of increase in extreme TW threshold exceedances under 2°C global warming. Results indicate that non-Gaussian TW distribution tails are common worldwide across extensive, spatially coherent regions. More rapid increases in the number of days exceeding the historical 95th percentile are projected in locations with shorter-than-Gaussian warm side tails. Asymmetry in the specific humidity distribution, one component of TW, is more closely correlated …

Plantation Pasts, Plantation Futures: Resisting Zombie Water Infrastructures In Maui, Hawai'i, Kelly Kay, Chris Knudson, Alida Cantor

Geography Faculty Publications and Presentations

Sugar plantations have fundamentally shaped water use in Maui, Hawai’i for over 100 years, with tremendous resulting impacts on ecosystems and Native Hawaiian communities. In this paper, we build on literature on the plantationocene and the political lives of infrastructure to examine plantation irrigation infrastructure. We center Maui’s vast water conveyance ditch system as a means of understanding how infrastructure continues plantation logics into the present, considering both the physical ditches themselves as well as the laws and politics which support continued water extraction. We also consider infrastructural futures, highlighting ongoing efforts of communities seeking water justice via infrastructural control.

Legal Geographies, Caroline Griffith, Sarah Klosterkamp, Alida Cantor, Austin Kocher

Geography Faculty Publications and Presentations

This encyclopedia entry defines and discusses legal geography. Legal geography is an interdisciplinary area of scholarship that focuses on the intersections and co-constitution between law and space and place: that is, how law and legal processes produce space/place, and how particular places in turn influence law. Rather than thinking of law as an abstract, universal, a-spatial set of rules, legal geography examines the ways in which law is situated in place, and how places are shaped by legal practices and processes.

Risk Analysis For Asset Protection In Hoyt Arboretum, Portland, Or, Nathan Kossnar

Masters in GIS Practicum Reports

In order to fulfill Tree Risk Assessment Qualification (TRAQ) certification obligations to the International Society of Arboriculture (ISA), this project delineated areas within Hoyt Arboretum where tree hazards have the potential to fall on important infrastructure and areas of frequent use. The project utilized Metro’s RLIS lidar data to generate a canopy height model which was then applied to a variable window filter (vwf) algorithm to determine individual tree heights and locations throughout the park. Previously defined protection areas were used to determine which surrounding trees have the potential to damage structures or injure park visitors in the chance of …

Community Gis Workshop Design & Delivery: Columbia County Geographic Workshop At Scappoose Public Library, Marty Marquis

Masters in GIS Practicum Reports

Geographic information systems (GIS) provide tools for industry, government, and the public to describe, visualize and organize space both conceptually and materially. Because the technology is complicated and potentially expensive, it is often out of the reach of those communities that might most benefit from its use, even as it’s routinely wielded by business interests, bureaucrats, and representative bodies to identify and legitimize administrative boundaries, potential areas for growth and profit, spatially oriented legislation (restricted areas, zoning), and so forth. Communities whose members know how to use a GIS gain potential advantages in deploying narratives that contest official plans for …

“Why You Always So Political?”: A Counterstory About Educational-Environmental Racism At A Predominantly White University, Martín Alberto Gonzalez

Chicano/Latino Studies Faculty Publications and Presentations

Using critical race counterstorytelling, I tell a story about the experiences of Mexican/Mexican American/Xicanx (MMAX) undergraduate students at private, historically and predominantly white university in the Northeast. Drawing on in-depth interviews, participant observations, pláticas, document analyses, and literature on race and space and racism in higher education, I argue that the racially hostile campus environment experienced by MMAX students at their respective university manifests itself as a form of educational-environmental racism. Through narrated dialogue, Aurora (a composite character) and I delve into a critical conversation about how educational-environmental racism is experienced by MMAX students through a racialized landscape in the …

Developing A Standard Operating Procedure For Irrigated Agricultural Field Delineation And Irrigation Identification Using Examples From The Oregon-Idaho Border And Central California, Scott Milleson

Masters in GIS Practicum Reports

This practicum draws from experience working as an intern for The Freshwater Trust (an environmental nonprofit organization based in Portland, Oregon) from June to December of 2022. The work performed in this internship involved the delineation of agricultural fields using ArcGIS Online, an online collaborative mapping tool, as well as identifying and assigning irrigation type attributes on the Oregon-Idaho border along the Snake River, and the Deschutes Basin.

The purpose of this practicum project is to create a generalized guide for the delineation of agricultural fields and identification of irrigation type using a standard operating procedure for GIS interns, mapathon …

Comparison Of Gis Methods For Estimating The Social Vulnerability In Response To Natural Hazards In The West Part Of The City Of Tualatin, Alex Troy

Geography Masters Research Papers

The influence of natural hazards on social vulnerability is an important topic in the risk analysis of natural disasters in the human-environment system. Due to the difficulty of directly measuring social vulnerability, composite indexes are used as a surrogate. Social vulnerability indexes attempt to characterize access to societal and local social services during or after disastrous events, using various indicators such as age, gender, ethnicity, socioeconomic status, housing organization, access to shelters, and medical facilities. Geographic information systems (GIS) are used for vulnerability analysis due to their visualization methods and demographic data analysis. However, limitations in GIS applications for social …

Isotopic Signature Of Massive, Buried Ice In Eastern Taylor Valley, Antarctica: Implications For Its Origin, Christopher B. Gardner, Melisa A. Diaz, Devin F. Smith, Andrew G. Fountain, Joseph S. Levy, W. Berry Lyons

Geography Faculty Publications and Presentations

The coastal regions of the McMurdo Dry Valleys, Antarctica, contain deposits of the Ross Sea Drift, sedimentary material left from the Ross Sea ice sheet from the advance of the West Antarctic ice sheet during the Last Glacial Maximum. Much of this deposit is ice-cored, but data on the stable isotopic composition of water from this ice, which may contain a valuable climate archive, are sparse or incomplete. Widespread thermokarstic ground subsidence in this “coastal thaw zone” of the McMurdo Dry Valleys suggests that these potential records are rapidly being lost due to the melting of ground ice and permafrost. …

Effects Of Antecedent Precipitation Amount And Covid-19 Lockdown On Water Quality Along An Urban Gradient, Daniel Ramirez, Heejun Chang, Katherine Gelsey

Geography Faculty Publications and Presentations

Water quality is affected by multiple spatial and temporal factors, including the surrounding land characteristics, human activities, and antecedent precipitation amounts. However, identifying the relationships between water quality and spatially and temporally varying environmental variables with a machine learning technique in a heterogeneous urban landscape has been understudied. We explore how seasonal and variable precipitation amounts and other small-scale landscape variables affect E. coli, total suspended solids (TSS), nitrogen-nitrate, orthophosphate, lead, and zinc concentrations in Portland, Oregon, USA. Mann–Whitney tests were used to detect differences in water quality between seasons and COVID-19 periods. Spearman’s rank correlation analysis was used to …

Flood Risk Perceptions And Future Migration Intentions Of Lagos Residents, Susan S. Ekoh, Lemir Teron, Idowu Ajibade, Silje Kristiansen

Geography Faculty Publications and Presentations

Coastal communities across the world face intense and frequent flooding due to the rise in extreme rainfall and storm surges associated with climate change. Adaptation is therefore crucial to manage the growing threat to coastal communities and cities. This case study focuses on Lagos, Nigeria, one of the world’s largest urban centers where rapid urbanization, poor urban planning, degrading infrastructure, and inadequate preparedness compounds flood vulnerability. We situate flood risk perceptions within the context of climate-induced mobilities in Lagos, which no study has done, filling a necessary knowledge gap. Furthermore, we apply a unique approach to flood risk perception and …

National Forest Visitation Preferences And Avenues To Participation For Urban Hispanic Recreationists In The Portland Metropolitan Area (Usa), Lee Cerveny, Rebecca Mclain, David Banis, Matthew Helmer

Geography Faculty Publications and Presentations

Health benefits of outdoor recreation have been broadly demonstrated and land managers recognize the equity implications of providing safe and inclusive outdoor spaces. Data on public lands visitation and outdoor participation show that Hispanic recreationists are less likely to engage in outdoor leisure than White persons. Early studies of outdoor preferences of Hispanic persons identified a desire for large-group settings and social activities. To update our understanding of outdoor recreation needs, preferences, and constraints, we collaborated with a Latinx organization in Portland, Oregon (USA). We collaboratively designed three focus groups that combined structured engagement, cognitive sorting, and participatory mapping to …