Geography Commons^™

Introduction: Managed Retreat And Environmental Justice In A Changing Climate, A. R. Siders, Idowu Ajibade

Geography Faculty Publications and Presentations

In response to global climate change, managed retreat has emerged as a controversial adaptation strategy. The purposeful movement of people and communities away from hazardous places raises numerous social and environmental justice concerns that will become even more pressing as retreat occurs more frequently and at larger scales. This special issue contributes to an emerging body of literature on managed retreat by providing a range of perspectives and approaches to considering justice in managed retreat. The assembled papers represent diverse voices(including perspectives from individuals whose communities are currently relocating or considering relocation), disciplines (including oral histories, legal analyses, and cultural …

Assessment Of Urban Flood Vulnerability Using The Social-Ecological-Technological Systems Framework In Six Us Cities, Heejun Chang, Arun Pallathadka, Jason Sauer, Nancy B. Grimm, Rae Zimmerman, Chingwen Cheng, David Iwaniec, Yeowon Kim, Multiple Additional Authors

Geography Faculty Publications and Presentations

As urban populations continue to grow through the 21st century, more people are projected to be at risk of exposure to climate change-induced extreme events. To investigate the complexity of urban floods, this study applied an interlinked social-ecological-technological systems (SETS) vulnerability framework by developing an urban flood vulnerability index for six US cities. Indicators were selected to reflect and illustrate exposure, sensitivity, and adaptive capacity to flooding for each of the three domains of SETS. We quantified 18 indicators and normalized them by the cities’ 500-yr floodplain area at the census block group level. Clusters of flood vulnerable areas were …

Portland Urban Coyote Project: A Review Of Citizen Science's Utility For Researching Urban Canids And The Human Environment, Keith David Vanderbrooke

Dissertations and Theses

The Portland Urban Coyote Project (PUCP) is a citizen science project that allows community members to upload coyote (Canis latrans) sighting data to a database that is used to create a public web map; contributors often add observations as well. I analyzed one year of PUCP comment data in order to assess the utility of the citizen science methods used by PUCP for urban carnivore research. I code and summarize findings from PUCP's data, compare the extracted data to other research studies of urban coyote from other regions, and find that results from this analysis supports conclusions made …

Climatic Controls On The Kinematics Of The Hooskanaden Landslide, Curry County, Oregon, Kara Kingen

Dissertations and Theses

Slow-moving earthflows represent major sources of sediment transport and erosion and are problematic for the management of critical infrastructure. The Hooskanaden Landslide -- a slow-moving earthflow on the southwest coast of Oregon -- crosses US Highway 101 and has been a site of continued interest to the Oregon Department of Transportation (ODOT) due to the weak lithology, erosive environment, and recurrent surge behavior (every ~15 years). Past surges, including the most recent (2019), have occurred during the winter, suggesting that velocity changes are predominantly controlled by climatic inputs. To examine the response of the Hooskanaden Landslide to seasonal and other …

Diagnosing Non-Gaussian Temperature Distribution Tails Using Back-Trajectory Analysis, A. J. Catalano, P. C. Loikith, J. D. Neelin

Geography Faculty Publications and Presentations

Coherent regions exhibiting non-Gaussian 2-m temperature distribution tails are present across the globe, indicating changes in extreme temperatures under future warming may manifest in more complex ways than were the underlying distributions symmetric about the mean. To further the understanding of physical processes that govern temperature distribution tail shape, this work utilizes a back-trajectory model to diagnose mechanisms for extreme daily mean temperature development at select extratropical locations exhibiting non-Gaussian tails. Although characteristics such as direction, distance, and temperature evolution vary among back-trajectories associated with extreme temperature days, results reveal principal pathways for air parcel propagation associated with preferred patterns …

Evaluation Of Manual And Semi-Automated Deep-Seated Landslide Inventory Processes: Willapa Hills, Washington, Tiffany E. Justice

Dissertations and Theses

Recent advances in remote sensing data and technology have allowed for computational models to be designed that successfully extract landforms from the landscape. The goal of this work is to create one such semi-automated model to extract deep-seated landslides located in complex geomorphic terrain. This is accomplished using geographic object-based image analysis (GEOBIA) techniques, considered by leaders in the field of image analysis to have an advantage over traditional automated classification methods. GEOBIA methods can mimic human visual interpretation by including more characteristic features used to assess the relationship between image data and the ground surface such as color reflectance …

The Influence Of Microsite Conditions On Early Performance Of Planted Nothofagus Nitida Seedlings When Restoring Degraded Coastal Temperate Rain Forests, Jan R. Bannister, Manuel Acevedo, German Travieso, Andres Holz, Nicole Galindo

Geography Faculty Publications and Presentations

Widespread impacts of changes in land use, climate, and disturbance regimes continue to affect mature forests and their subsequent post-disturbance recovery. In South American temperate rainforests, the recovery of the original composition, structure, and ecological services of now-degraded old-growth forests is additionally hampered by the aggressive competition that the native Chusquea bamboo understory exerts on juvenile trees, thus arresting ecological succession. In this study, we aim to evaluate the early performance of Nothofagus nitida seedlings (pioneer tree species that tolerate shade) planted beneath nurse canopy following removal of the understory, and to define which microsite conditions can facilitate N. nitida …

Regulators And Utility Managers Agree About Barriers And Opportunities For Innovation In The Municipal Wastewater Sector, Alida Cantor, Luke Sherman, Anita Milman, Michael Kiparsky

Geography Faculty Publications and Presentations

Despite pressures to improve performance and reduce costs, innovation in the municipal wastewater sector in the United States has been notoriously slow. Previous research has suggested that wastewater utility managers may see regulation as a barrier to developing and deploying new technologies. To better understand how environmental regulation may fuel or hinder innovation in this sector, we conducted a nationwide survey of wastewater utility managers and wastewater regulators in the United States, asking both populations about their perceptions of specific aspects of regulation and innovation. Survey results revealed broad agreement between the two groups that funding and capacity, regulatory relationships, …

Combating Ecosystem Collapse From The Tropics To The Antarctic, Dana M. Bergstrom, Barbara C. Wienecke, John Van Den Hoff, Lesley Hughes, David B. Lindenmayer, Tracy D. Ainsworth, Christopher M. Baker, Lucie Bland, David M J S Bowman, Shaun T. Brooks, Josep G. Canadell, Andrew J. Constable, Katherine A. Dafforn, Michael H. Depledge, Catherine R. Dickson, Norman C. Duke, Kate J. Helmstedt, Andrés Holz

Geography Faculty Publications and Presentations

Globally, collapse of ecosystems-potentially irreversible change to ecosystem structure, composition and function-imperils biodiversity, human health and well-being. We examine the current state and recent trajectories of 19 ecosystems, spanning 58° of latitude across 7.7 M km , from Australia's coral reefs to terrestrial Antarctica. Pressures from global climate change and regional human impacts, occurring as chronic 'presses' and/or acute 'pulses', drive ecosystem collapse. Ecosystem responses to 5-17 pressures were categorised as four collapse profiles-abrupt, smooth, stepped and fluctuating. The manifestation of widespread ecosystem collapse is a stark warning of the necessity to take action. We present a three-step assessment and …

The Value Of Urban Flood Modeling, B. R. Rosenweig, P. Herreros Cantis, Y. Kim, A. Cohn, K. Grove, J. Brock, Heejun Chang, Multiple Additional Authors

Geography Faculty Publications and Presentations

Floods are important disturbances to urban socio-eco-technical systems and their meteorological drivers are projected to increase through the century due to global climate change. Urban flood models are numerical models that have the capability of representing the features of urban ecosystems and the mechanisms of flooding that impact them. They have the potential to play a critical role in flood risk assessment, operational response, and resilience planning, but existing models remain limited in their capability to represent integrated flooding processes in urban areas and provide the credible quantitative information needed to support risk assessment and resilience practice. Research to advance …

Assessing Airborne Radar To Map Glacier Elevations In Alpine Terrain Including Estimated Glacier Volume Change, Bryce Allen Glenn

Dissertations and Theses

Alpine glaciers and perennial snowfields (G&PS) are important hydrologically and ecologically, providing meltwater during the hottest and driest summer periods. Climate warming shrinks these natural reservoirs while temporarily providing increased streamflow. To assess regional changes in glacier volume, from which contribution to streamflow can be estimated, I used NASA's Airborne Glacier and Ice Surface Topography Interferometer (GLISTIN). This instrument mapped the surface topography of alpine glaciers; differencing these elevations from historic elevations derived from topographic maps, volume change is calculated. GLISTIN was flown over the glacier-populated mountain ranges of the western U.S. Of the 3289 glaciers and perennial snowfields with …

Environmental And Spatial Factors Affecting Surface Water Quality In A Himalayan Watershed, Central Nepal, Janardan Mainali, Heejun Chang

Geography Faculty Publications and Presentations

Various spatial interrelationships among sampling stations are not well explored in the spatial modeling of water quality literature. This research explores the relationship between water quality and various social, demographic, and topographic factors in an urbanizing watershed of Nepal with a comparison of different connectivity matrices to conceptualize spatial interrelationships. We collected electrical conductivity and dissolved oxygen data from surface water bodies using a handheld probe and used the data to establish relationships with land use, topography, and population density-based explanatory variables at both watershed and 100-m buffer scales. The linear regression model was compared with different eigenvector-based spatial filtering …

The Right To Urban Streams: Quantitative Comparisons Of Stakeholder Perceptions In Defining Adaptive Stream Restoration, Chang-Yu Hong, Eun-Sung Chung, Heejun Chang

Geography Faculty Publications and Presentations

Assuring healthy streams in the urban environment is a major goal for restoration scientists, urban planners, and city practitioners around the globe. In South Korea, many urban stream restoration efforts are designed to provide safe water to society and enhance ecological functions. We examined the extent to which the individual interests and different values of multiple stakeholders were considered in previous decision-making in two urban stream restoration projects. The relevant data on stream restoration were collected through the nominal group technique (NGT) and the analytic hierarchy process (AHP) for the two stream cases of a populated inland area and a …

High-Severity And Short-Interval Wildfires Limit Forest Recovery In The Central Cascade Range, Sebastian Upton Busby, Kevan B. Moffett, Andres Holz

Geography Faculty Publications and Presentations

Increasing forest fuel aridity with climate change may be expanding mid-to-high-elevation forests’ vulnerability to large, severe, and frequent wildfire. Long-lasting changes in forests’ structure and composition may occur if dominant tree species are poorly adapted to shifting wildfire patterns. We hypothesized that altered fire activity may lower existing forest resilience and disrupt the recovery of upper-montane and subalpine conifer forest types. We empirically tested this hypothesis by quantifying post-fire forest structure and conifer tree regeneration after spatially large, severe, and rapidly repeated wildfires (

Variability In Historical Fire Patterns Of A Moist Mixed-Conifer Forest In The Northern Blue Mountains Of Oregon, Laura Marie Platt

Dissertations and Theses

High variability in historical fire patterns characteristic to mixed-severity fire regimes is expected to have contributed to a structurally heterogeneous landscape throughout much of the forested ecosystems of the western United States. After more than a hundred years of fire exclusion in the region, many forests have shifted to a more homogeneous structure, which raises concern regarding these forests' ability to sustain expected increases in fire activity with a warming climate. The shift is not uniform across the west, however, and differences in historical disturbance patterns and changes due to land management are not well characterized in forests across a …

Pre-Emptive Detection Of Mature Pine Drought Stress Using Multispectral Aerial Imagery, Nancy Grulke, Jason Maxfield, Phillip Riggan, Charlie Schrader-Patton

Biology Faculty Publications and Presentations

Drought, ozone (O₃), and nitrogen deposition (N) alter foliar pigments and tree crown structure that may be remotely detectable. Remote sensing tools are needed that pre-emptively identify trees susceptible to environmental stresses could inform forest managers in advance of tree mortality risk. Jeffrey pine, a component of the economically important and widespread western yellow pine in North America was investigated in the southern Sierra Nevada. Transpiration of mature trees differed by 20% between microsites with adequate (mesic (M)) vs. limited (xeric (X)) water availability as described in a previous study. In this study, in-the-crown morphological traits (needle chlorosis, …

A Multivariate Assessment Of Climate Change Projections Over South America Using Cmip5, Valerie Maria Thaler

Dissertations and Theses

A multivariate assessment of climate model projections over South America from the CMIP5 archive is presented. Change in near-surface temperature, precipitation, evapotranspiration, integrated water vapor transport (IVT), sea level pressure, and wind at multiple pressure levels is quantified across the multi-model suite and an assessment of model-to-model agreement on projected change performed. All models project warming by the mid- and late-21st century throughout the continent, with the highest magnitude projected over tropical regions. The CMIP5 models are in strong agreement that precipitation will decrease in all seasons over portions of Patagonia, especially along the northern portions of the current-climate mid-latitude …

Assessing Adaptive Capacity To Climate And Population Change At The Urban-Rural Interface: Human-Water System Dynamics In The Hood River Valley, Oregon, Alexander Reid Ross

Dissertations and Theses

An exurban nook on the Oregon side of the Columbia River Gorge named after the Hood River that runs northward from the glaciers of Mount Hood to the confluence seems ideally poised for the kind of relaxed, natural lifestyle that once brought suburban areas their appeal. However, like other exurban areas, Hood River also lies at an uncertain fault-line between economic and environmental transformation in the U.S.'s exurbs.

This study maps the socio-economic and climatological transformations of exurban areas as they contend with different approaches to sustainability and resilience. To determine the major climate and development hazards facing exurban areas …

Wildlife Connectivity Modeling For The Northern Red-Legged Frog In The Portland Metropolitan Area, Oregon, Amanda Hilary Temple

Dissertations and Theses

Effective habitat connectivity tools that use GIS data perform well in remote areas but may not be as dependable in urban environments. The goal was to study uses and limitations of a conservation management tool in development, the Metro Regional Habitat Connectivity Toolkit, which evaluates connectivity for and permeability of wildlife movement. Habitat quality scores are generated from GIS-derived and field collected data such as connectivity patch/matrix characteristics, water source, vegetation, other structural components, wildlife observations, and human disturbance at survey sites. I compared GIS and field generated habitat quality scores for the Northern Red-legged Frog (Rana aurora) …

A 30-Yr Climatology Of Meteorological Conditions Associated With Lightning Days In The Interior Western United States, Dmitri Alexander Kalashnikov, Paul Loikith, Arielle J. Catalano, Duane E. Waliser, Huikyo Lee, John T. Abatzoglou

Geography Faculty Publications and Presentations

A 30-yr climatology of lightning days and associated synoptic meteorological patterns are characterized across the interior western United States (WUS). Locally centered composite analyses show preferred synoptic meteorological patterns with positive 500-hPa geopotential height anomalies located to the northeast and negative sea level pressure anomalies to the northwest and collocated with local lightning days. Variations in preferred patterns for local lightning days are seen across the interior WUS. Areas not commonly affected by the North American monsoon system including the western Great Basin and northern Rocky Mountains show higher-amplitude anomalies of geopotential height, moisture, and midtropospheric instability patterns suggesting the …

Unpacking The Process And Outcomes Of Ethical Markets: A Focus On Certified B Corporations, Renée Bogin Curtis

Dissertations and Theses

The growth in conscious consumption presents an opportunity to 1) better understand the potential outcomes of ethical market practices as a community-advocacy tool and 2) to consider potential policy considerations. The marketplace has increasingly become an arena for social action. This leads to the question of how can markets facilitate ethical business practices and community benefits? The recent rise of social benefit corporations warrants an evaluation of the outcomes of ethically-driven markets. Using a comparative research design and qualitative interview methods, this study examines certified Benefit Corporations (B Corps) in two selected cities: Philadelphia and Portland. Through interviews with B …

Warmer Conditions Favor Conifer Tree Establishment At The Muddy River Lahar In Mt. St. Helens, Washington, Ignacio D. Falcon-Dvorsky

Dissertations and Theses

Climate variability impacts on Pacific Northwest forests are of great concern, especially on evergreen coniferous ecosystems which dominate a large portion of the landscape. Understanding the effect of climate variability and its potential impacts on forest regeneration is crucial, as this is a foundational process with long-lasting consequences on structure and composition of future ecosystems. The objective of this study was to uncover the possible influences of natural climate variability on conifer tree establishments on the Muddy Rivers Lahar following the 1980 eruption of Mount St. Helens, WA. We hypothesized that tree establishment increased gradually over time, tree establishments was …

Legal Geographies And Political Ecologies Of Water Allocation In Maui, Hawai'i, Alida Cantor, Kelly Kay, Chris Knudson

Geography Faculty Publications and Presentations

Throughout the Hawaiian Islands, sugar plantations have controlled a large proportion of water resources for over a century, often leaving little water in streams to support ecosystems or Native Hawaiian cultural and agricultural practices. Recently, in Maui, Hawai‘i, community activists and lawyers representing Native Hawaiian and environmental interests have successfully reclaimed water resources for instream flow utilizing legal processes and tools such as Hawai‘i’s public trust doctrine, which has plural roots in both Hawaiian and Western legal traditions. In this paper, we use qualitative fieldwork, including interviews, participant observation, and archival data collection, to explore two recent and ongoing legal …

Population Collapse And Retreat To Fire Refugia Of The Tasmanian Endemic Conifer Athrotaxis Selaginoides Following The Transition From Aboriginal To European Fire Management, Andres Holz, Samuel W. Wood, Carly Ward, Thomas T. Veblen, David M.J.S. Bowman

Geography Faculty Publications and Presentations

Untangling the nuanced relationships between landscape, fire disturbance, human agency, and climate is key to understanding rapid population declines of fire‐sensitive plant species. Using multiple lines of evidence across temporal and spatial scales (vegetation survey, stand structure analysis, dendrochronology, and fire history reconstruction), we document landscape‐scale population collapse of the long‐lived, endemic Tasmanian conifer Athrotaxis selaginoides in remote montane catchments in southern Tasmania. We contextualized the findings of this field‐based study with a Tasmanian‐wide geospatial analysis of fire‐killed and unburned populations of the species. Population declines followed European colonization commencing in 1802 ad that disrupted Aboriginal landscape burning. Prior to …

Glacial Meltwater Modeling To Simulate Lake Water Budget (1996-2013) In Taylor Valley, Antarctica, Julian Michael Cross

Dissertations and Theses

The McMurdo Dry Valleys (MDV), the largest ice-free region (4,500 km²) in Antarctica, are a polar desert with an average annual temperature of -18ºC. In Taylor Valley, one of the MDV, closed-basin, perennially ice-covered lakes occupy the valley floor. Their water balance is controlled by inflow from glacial meltwater runoff and loss due to sublimation, making them sensitive indicators of climate. In this study, a physically-based model of glacier meltwater and lake ice sublimation is adapted to explain modern (1996 to 2013) lake-level variations. Meltwater model results were improved by the inclusion of MODIS remotely-sensed albedo measurements (E …

Disturbance Refugia Within Mosaics Of Forest Fire, Drought, And Insect Outbreaks, Meg A. Krawchuk, Garrett W. Meigs, Jennifer M. Cartwright, Jonathan D. Coop, Raymond Davis, Andres Holz, Crystal Kolden, Arjan Jh Meddens

Geography Faculty Publications and Presentations

Disturbance refugia – locations that experience less severe or frequent disturbances than the surrounding landscape – provide a framework to highlight not only where and why these biological legacies persist as adjacent areas change but also the value of those legacies in sustaining biodiversity. Recent studies of disturbance refugia in forest ecosystems have focused primarily on fire, with a growing recognition of important applications to land management. Given the wide range of disturbance processes in forests, developing a broader understanding of disturbance refugia is important for scientists and land managers, particularly in the context of anthropogenic climate change. We illustrate …

Socio-Hydrology: An Interplay Of Design And Self-Organization In A Multilevel World, David J. Yu, Heejun Chang, Taylor T. Davis, Vicken Hillis, Landon T. Marston, Woi Sok Oh, Murugesu Sivapalan, Timothy M. Waring

Geography Faculty Publications and Presentations

The emerging field of socio-hydrology is a special case of social-ecological systems research that focuses on coupled human-water systems, exploring how the hydrologic cycle and human cultural traits coevolve and how such coevolutions lead to phenomena of relevance to water security and sustainability. As such, most problems tackled by socio-hydrology involve some aspects of engineering design, such as large-scale water infrastructure, and self-organization in a broad context, such as cultural change at the population level and the hydrologic shift at the river basin or aquifer level. However, within the field of socio-hydrology, it has been difficult to find general theories …

A Digital Archive Of Human Activity In The Mcmurdo Dry Valleys, Antarctica, Adrian Howkins, Stephen M. Chignell, Poppie Gullett, Andrew G. Fountain, Melissa Carrie Brett, Evelin Preciado

Geography Faculty Publications and Presentations

Over the last half century, the McMurdo Dry Valleys (MDV) of East Antarctica have become a globally important site for scientific research and environmental monitoring. Historical data can make important contributions to current research activities and environmental management in Antarctica but tend to be widely scattered and difficult to access. We address this need in the MDV by compiling over 5000 historical photographs, sketches, maps, oral interviews, publications, and other archival resources into an online digital archive. The data have been digitized and georeferenced using a standardized metadata structure, which enables intuitive searches and data discovery via an online interface. …

Dropsonde Observations Of The Ageostrophy Within The Pre-Cold-Frontal Low-Level Jet Associated With Atmospheric Rivers, Rueben Demirdgian, Joel R. Norris, Andrew Martin, F. Martin Ralph

Geography Faculty Publications and Presentations

The pre-cold-frontal low-level jet (LLJ) is an important contributor for water vapor transport within atmospheric rivers, though its dynamics are not completely understood. The present study investigates the LLJ using dropsonde observations from 24 cross-atmospheric river transects taken during the CalWater-2014, 2015 and the AR-Recon 2016, 2018 field campaigns. It is found that the LLJ, located at ;1-km elevation ahead of the cold front, has an average maximum wind speed of 30ms21 and is strongly supergeostrophic with an average ageostrophic component of 6ms21. The alongfront ageostrophy occurs within the atmospheric layer (750–1250 m) known to strongly control orographic precipitation associated …

Associations Of Neighborhood Socioeconomic Conditions With Self-Rated Health, Mental Distress, And Health Behaviors: A Nationwide Cross-Sectional Study In Japan, Tomoya Hanibuchi, Tomoki Nakaya

Geography Faculty Publications and Presentations

Although associations between neighborhood socioeconomic conditions and health have been well established, their geographical scope is mostly limited to Western societies, while multilevel studies in the non-Western context (e.g., Japan) are limited to specific cities/regions within countries. This consequently limits the external validity of the findings. To fill the gap, this study examined the associations between neighborhood socioeconomic conditions and health-related indicators by using nationwide cross-sectional data in Japan. Individual data was collected from a nationwide online survey conducted in 2015 (n = 4593). Self-rated health, mental distress (Kessler Psychological Distress Scale: K6), smoking, and physical activity were analyzed in …