Physical Sciences and Mathematics Commons^™

Spatial And Temporal Variations Of Microplastic Concentrations In Portland's Freshwater Ecosystems, Rebecca Talbot, Elise F. Granek, Heejun Chang, Rosemary Wood, Susanne Brander

Geography Faculty Publications and Presentations

While microplastics are a pollutant of growing concern in various environmental compartments, less is known regarding the sources and delivery pathways of microplastics in urban rivers. We investigated the relationship between microplastic concentrations and various spatiotemporal factors (e.g., land use, arterial road length, water velocity, precipitation) in two watersheds along an urban-rural gradient in the Portland metropolitan area. Samples were collected in August, September, and February and were analyzed for total microplastic count and type. Nonparametric statistics were used to evaluate potential relationships with the explanatory variables, derived at both the subwatershed and near stream scales. In August, microplastic concentrations …

A Community Of Fear: Emotion And The Hydro-Social Cycle In East Porterville, California, Michael Egge, Idowu Ajibade

Geography Faculty Publications and Presentations

Broader governance challenges driving water insecurity globally are well documented in the literature, however the power-laden relationships and emotions that shape water access at the household and community levels are yet to be fully investigated, especially in the context of water consolidation projects. In this article, we examine the role of emotions in mediating access to water and in the production of resource struggles among marginalized communities, existing outside of conventional regulatory frameworks. We bring together two relational approaches – the hydro-social cycle and emotional political ecology – to examine water insecurity and how it manifests in the historically disadvantaged …

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. …

Examining The Complex Relationship Between Innovation And Regulation Through A Survey Of Wastewater Utility Managers, Luke Sherman, Alida Cantor, Anita Milman, Michael Kiparsky

Geography Faculty Publications and Presentations

Despite pressures to increase performance and decrease costs, innovation has been slow to emerge in the municipal wastewater sector. The relationship between regulation and innovation in this sector is a particularly interesting aspect of this conundrum, given the degree to which public utility decision-making is influenced by regulation. Using a national survey, this paper examines US wastewater utility managers’ perceptions of how regulation influences the adoption of new technologies. Recognizing that the relationship between innovation and regulation is complex, we develop the concept of regulation as multifaceted and examine three interrelated aspects of regulation: (1) regulatory requirements, (2) regulators and …

The Fire And Tree Mortality Database, For Empirical Modeling Of Individual Tree Mortality After Fire, C. Alina Cansler, Sharon M. Hood, J. Morgan Varner, Phillip J. Van Mantgem, Michelle C. Agne, Matthew Ayres, Robert A. Andrus, Jonathon D. Bakker, Michael A. Battaglia, Shelby A. Weiss, Multiple Additional Authors

Geography Faculty Publications and Presentations

Wildland fires have a multitude of ecological effects in forests, woodlands, and savannas across the globe. A major focus of past research has been on tree mortality from fire, as trees provide a vast range of biological services. We assembled a database of individual-tree records from prescribed fires and wildfires in the United States. The Fire and Tree Mortality (FTM) database includes records from 164,293 individual trees with records of fire injury (crown scorch, bole char, etc.), tree diameter, and either mortality or top-kill up to ten years post-fire. Data span 142 species and 62 genera, from 409 fires occurring …

Patterns And Drivers Of Recent Disturbances Across The Temperate Forest Biome, Andreas Sommerfeld, Cornelius Senf, Brian Buma, Anthony W. D'Amato, Tiphaine Despres, Ignacio Díaz-Hormazábal, Shawn Fraver, Lee E. Frelich, Alvaro G. Gutiérrez, Sarah J. Hart, Brian J. Harvey, Hong S. He, Tomáš Hlásny, Andrés Holz, Multiple Additional Authors

Geography Faculty Publications and Presentations

Increasing evidence indicates that forest disturbances are changing in response to global change, yet local variability in disturbance remains high. We quantified this considerable variability and analyzed whether recent disturbance episodes around the globe were consistently driven by climate, and if human influence modulates patterns of forest disturbance. We combined remote sensing data on recent (2001–2014) disturbances with in-depth local information for 50 protected landscapes and their surroundings across the temperate biome. Disturbance patterns are highly variable, and shaped by variation in disturbance agents and traits of prevailing tree species. However, high disturbance activity is consistently linked to warmer and …

Sources Of Contaminated Flood Sediments In A Rural–Urban Catchment: Johnson Creek, Oregon, Heejun Chang, Deonie Allen, Jennifer L. Morse, Janardan Mainali

Geography Faculty Publications and Presentations

This study investigated the delivery of contaminated sediments to the channel network by urban drainage systems in Johnson Creek in Oregon, USA. Concentrations of five heavy metal concentrations measured in 136 samples collected from 37 stormwater outfalls and 99 bed sampling points were analysed. While concentrations of zinc, cadmium and lead increased with distance downstream in Johnson Creek, this was not the case for chromium and copper. Zinc, copper, and cadmium concentrations in outfalls were significantly higher than those in the stream bed, indicating that stormwater runoff is responsible for delivering contaminated sediments to Johnson Creek. Zinc concentrations in outfalls …

Africa's Urban Adaptation Transition Under A 1.5° Climate, Mark Pelling, Hayley Leck, Lorena Pasquini, Idowu Ajibade, Emanuel Osuteye, Susan Parnell, Shuaib Lwasa, Cassidy Johnson, Arabella Fraser, Alejandro Barcena, Soumana Boubacar

Geography Faculty Publications and Presentations

For cities in sub-Saharan Africa a 1.5 °C increase in global temperature will bring forward the urgency of meeting basic needs in sanitation, drinking water and land-tenure, and underlying governance weaknesses. The challenges of climate sensitive management are exacerbated by rapid population growth, deep and persistent poverty, a trend for resolving risk through relocation (often forced), and emerging new risks, often multi-hazard, for example heat stroke made worse by air pollution. Orienting risk management towards a developmental agenda can help. Transition is constrained by fragmented governance, donor priorities and inadequate monitoring of hazards, vulnerability and impacts. Opportunities arise where data …

Newwater Regimes: An Editorial, Alida Cantor, Jacque Emel

Geography Faculty Publications and Presentations

This editorial is an introduction to the special issue of Resources on New Water Regimes. The special issue explores legal geographies of water resource management with the dual goals of providing critiques of existing water management practices as well as exploring potential alternatives. The papers in the special issue draw from numerous theoretical perspectives, including decolonial and post-anthropocentric approaches to water governance; social and environmental justice in water management; and understanding legal ecologies. A variety of themes of water governance are addressed, including water allocation, groundwater management, collaborative governance, drought planning, and water quality. The papers describe and analyze water …

Multiple Methods Of Public Engagement: Disaggregating Socio-Spatial Data For Environmental Planning In Western Washington, Usa, Rebecca J. Mclain, David Banis, Alexa Todd, Lee Cerveny

Geography Faculty Publications and Presentations

Highlights

• The effectiveness of participatory GIS approaches at engaging different publics was explored.

• Online surveys engaged urbanites; community workshops engaged rural residents.

• Urban and rural residents went to similar places but engaged in different activities.

• Use of multiple data collection methods will broaden public engagement.

• Mapping behavior studies are needed to improve understandings of PPGIS data quality.

Finding Water Scarcity Amid Abundance Using Human–Natural System Models, William K. Jaeger, Adell Amos, Daniel P. Bigelow, Heejun Chang, David R. Conklin, Roy Haggerty, Christian Langpap, Kathleen Moore, Philip Mote, Anne W. Nolin, Andrew J. Plantinga, Cynthia L. Schwartz, Desiree Tullos, David P. Turner

Geography Faculty Publications and Presentations

Water scarcity afflicts societies worldwide. Anticipating water shortages is vital because of water’s indispensable role in social-ecological systems. But the challenge is daunting due to heterogeneity, feedbacks, and water’s spatial-temporal sequencing throughout such systems. Regional system models with sufficient detail can help address this challenge. In our study, a detailed coupled human–natural system model of one such region identifies how climate change and socioeconomic growth will alter the availability and use of water in coming decades. Results demonstrate how water scarcity varies greatly across small distances and brief time periods, even in basins where water may be relatively abundant overall. …

Quantifying Resilience Of Multiple Ecosystem Services And Biodiversity In A Temperate Forest Landscape, Elena Cantarello, Adrian C. Newton, Phillip A. Martin, Paul M. Evans, Arjan Gosal, Melissa S. Lucash

Geography Faculty Publications and Presentations

Resilience is increasingly being considered as a new paradigm of forest management among scientists, practitioners, and policymakers. However, metrics of resilience to environmental change are lacking. Faced with novel disturbances, forests may be able to sustain existing ecosystem services and biodiversity by exhibiting resilience, or alternatively these attributes may undergo either a linear or nonlinear decline. Here we provide a novel quantitative approach for assessing forest resilience that focuses on three components of resilience, namely resistance, recovery, and net change, using a spatially explicit model of forest dynamics. Under the pulse set scenarios, we explored the resilience of nine ecosystem …

Values Mapping And Counter-Mapping In Contested Landscapes: An Olympic Peninsula (Usa) Case Study, Rebecca J. Mclain, Lee Cerveny, Kelly Biedenweg, David Banis

Geography Faculty Publications and Presentations

Indigenous peoples, local communities, and other groups can use counter-mapping to make land claims, identify areas of desired access, or convey cultural values that diverge from the dominant paradigm. While sometimes created independently, counter-maps also can be formulated during public participation mapping events sponsored by natural resource planning agencies. Public participation mapping elicits values, uses, and meanings of landscapes from diverse stakeholders, yet individuals and advocacy groups can use the mapping process as an opportunity to make visible strongly held values and viewpoints. We present three cases from the Olympic Peninsula in Washington State to illustrate how stakeholders intentionally used …

The Influence Of Recurrent Modes Of Climate Variability On The Occurrence Of Monthly Temperature Extremes Over South America, Paul C. Loikith, Judah Detzer, Carlos R. Mechoso, Huikyo Lee, Armineh Barkhordarian

Geography Faculty Publications and Presentations

The associations between extreme temperature months and four prominent modes of recurrent climate variability are examined over South America. Associations are computed as the percent of extreme temperature months concurrent with the upper and lower quartiles of the El Niño–Southern Oscillation (ENSO), the Atlantic Niño, the Pacific Decadal Oscillation (PDO), and the Southern Annular Mode (SAM) index distributions, stratified by season. The relationship is strongest for ENSO, with nearly every extreme temperature month concurrent with the upper or lower quartiles of its distribution in portions of northwestern South America during some seasons. The likelihood of extreme warm temperatures is enhanced …

Southern Annular Mode Drives Multicentury Wildfire Activity In Southern South America, Andrés Holz, Juan Paritsis, Ignacio A. Mundo, Thomas T. Veblen, Thomas Kitzberger, Grant J. Williamson, Ezequiel Aráoz, Carlos Bustos-Schindler, Mauro E. González, H. Ricardo Grau, Juan M. Quezada

Geography Faculty Publications and Presentations

The Southern Annular Mode (SAM) is the main driver of climate variability at mid to high latitudes in the Southern Hemisphere, affecting wildfire activity, which in turn pollutes the air and contributes to human health problems and mortality, and potentially provides strong feedback to the climate system through emissions and land cover changes. Here we report the largest Southern Hemisphere network of annually resolved tree ring fire histories, consisting of 1,767 fire-scarred trees from 97 sites (from 22 °S to 54 °S) in southern South America (SAS), to quantify the coupling of SAM and regional wildfire variability using recently created …

Watershed Response To Climate Change And Fire-Burns In The Upper Umatilla River Basin, Usa, Kimberly Crystal Yazzie, Heejun Chang

Geography Faculty Publications and Presentations

This study analyzed watershed response to climate change and forest fire impacts in the upper Umatilla River Basin (URB), Oregon, using the precipitation runoff modeling system. Ten global climate models using Coupled Intercomparison Project Phase 5 experiments with Representative Concentration Pathways (RCP) 4.5 and 8.5 were used to simulate the effects of climate and fire-burns on runoff behavior throughout the 21st century. We observed the center timing (CT) of flow, seasonal flows, snow water equivalent (SWE) and basin recharge. In the upper URB, hydrologic regime shifts from a snow-rain-dominated to rain-dominated basin. Ensemble mean CT occurs 27 days earlier in …

Evaluating Hourly Rainfall Characteristics Over The U.S. Great Plains In Dynamically Downscaled Climate Model Simulations Using Nasa-Unified Wrf, Huikyo Lee, Duane E. Waliser, Robert Ferraro, Takamichi Iguchi, Christa D. Peters-Lidard, Baijun Tian, Paul C. Loikith, Daniel B. Wright

Geography Faculty Publications and Presentations

Accurate simulation of extreme precipitation events remains a challenge in climate models. This study utilizes hourly precipitation data from ground stations and satellite instruments to evaluate rainfall characteristics simulated by the NASA-Unified Weather Research and Forecasting (NU-WRF) regional climate model at horizontal resolutions of 4, 12, and 24 km over the Great Plains of the United States. We also examined the sensitivity of the simulated precipitation to different spectral nudging approaches and the cumulus parameterizations. The rainfall characteristics in the observations and simulations were defined as an hourly diurnal cycle of precipitation and a joint probability distribution function (JPDF) between …

The Influence Of Floodplain Restoration On Flow And Sediment Dynamics In An Urban River, Sangaralingam Ahilan, Mingfu Guan, Andrew Sleigh, Nigel G. Wright, Heejun Chang

Geography Faculty Publications and Presentations

A study of floodplain sedimentation on a recently restored floodplain is presented. This study uses a two-dimensional hydro-morphodynamic model for predicting flow and suspended-sediment dynamics in the downstream of Johnson Creek, the East Lents reach, where the bank of the river has been reconfigured to reconnect to a restored floodplain on a 0.26 km² (26-ha) site. The simulation scenarios include 10-, 50-, 100- and 500-year event-based deposition modelling of flood events and long-term modelling using the 64 historical flood events between 1941 and 2014. Simulation results showed that the restored floodplain significantly attenuates the upstream flood peak by up …

Evaluation Of Large‑Scale Meteorological Patterns Associated With Temperature Extremes In The Narccap Regional Climate Model Simulations, Paul C. Loikith, Duane E. Waliser, Huikyo Lee, J. David Neelin, Benjamin Lintner, Seth Mcginnis, Linda Mears, Jinwon Kim

Geography Faculty Publications and Presentations

Large-scale meteorological patterns (LSMPs) associated with temperature extremes are evaluated in a suite of regional climate model (RCM) simulations contributing to the North American Regional Climate Change Assessment Program. LSMPs are characterized through composites of surface air temperature, sea level pressure, and 500 hPa geopotential height anomalies concurrent with extreme temperature days. Six of the seventeen RCM simulations are driven by boundary conditions from reanalysis while the other eleven are driven by one of four global climate models (GCMs). Four illustrative case studies are analyzed in detail. Model fidelity in LSMP spatial representation is high for cold winter extremes near …

Utilizing Humidity And Temperature Data To Advance Monitoring And Prediction Of Meteorological Drought, Ali Behrangi, Paul C. Loikith, Eric J. Fetzer, Hai M. Nguyen, Stephanie L. Granger

Geography Faculty Publications and Presentations

The fraction of land area over the Continental United States experiencing extreme hot and dry conditions has been increasing over the past several decades, consistent with expectation from anthropogenic climate change. A clear concurrent change in precipitation, however, has not been confirmed. Vapor pressure deficit (VPD), combining temperature and humidity, is utilized here as an indicator of the background atmospheric conditions associated with meteorological drought. Furthermore, atmospheric conditions associated with warm season drought events are assessed by partitioning associated VPD anomalies into the temperature and humidity components. This approach suggests that the concurrence of anomalously high temperature and low humidity …

Comparison Between Observed And Model-Simulated Atmospheric Circulationpatterns Associated With Extreme Temperature Days Over North Americausing Cmip5 Historical Simulations, Paul C. Loikith, Anthony J. Broccoli

Geography Faculty Publications and Presentations

Circulation patterns associated with extreme temperature days over North America, as simulated by a suite of climate models, are compared with those obtained from observations. The authors analyze 17 coupled atmosphere–ocean general circulation models contributing to the fifth phase of the Coupled Model Intercomparison Project. Circulation patterns are defined as composites of anomalies in sea level pressure and 500-hPa geopotential height concurrent with days in the tails of temperature distribution. Several metrics used to systematically describe circulation patterns associated with extreme temperature days are applied to both the observed and model-simulated data. Additionally, self-organizing maps are employed as a means …

Surface Temperature Probability Distributions In The Narccap Hindcast Experiment: Evaluation Methodology, Metrics, And Results, Paul C. Loikith, Duane E. Waliser, Huikyo Lee, Jinwon Kim, J. David Neelin, Benjamin R. Lintner, Seth Mcginnis, Chris A. Mattmann, Linda O. Mears

Geography Faculty Publications and Presentations

Methodology is developed and applied to evaluate the characteristics of daily surface temperature distributions in a six-member regional climate model (RCM) hindcast experiment conducted as part of the North American Regional Climate Change Assessment Program (NARCCAP). A surface temperature dataset combining gridded station observations and reanalysis is employed as the primary reference. Temperature biases are documented across the distribution, focusing on the median and tails. Temperature variance is generally higher in the RCMs than reference, while skewness is reasonably simulated in winter over the entire domain and over the western United States and Canada in summer. Substantial differences in skewness …

Discourses Of Deflection: The Politics Of Framing China’S South North Water Transfer Project, Britt Crow-Miller

Geography Faculty Publications and Presentations

Despite significant financial, ecological and social trade-offs, China has moved forward with constructing and operationalising the world’s largest interbasin water transfer project to date, the South-North Water Transfer Project (SNWTP). While it is fundamentally linked to broader political-economic goals within the context of China’s post-Mao development agenda, the SNWTP is frequently discussed in apolitical terms. Based on extensive discourse analysis and interviews with government officials across North China, I argue that the Chinese government is using "discourses of deflection" to present the project as politically neutral in order to serve its ultimate goal of maintaining the high economic growth rates …

Self-Reported Experiences Of Climate Change In Nigeria: The Role Of Personal And Socio-Environmental, Idowu Ajibade, Frederick Ato Armah, Vincent Kuuire, Isaac Luginaah, Gordon Mcbean

Geography Faculty Publications and Presentations

In this study, we examined the individual and socio-environmental factors that mediate differential self-reported experiences of climate change in coastal communities in Lagos, Nigeria. Binary complementary log-log multivariate regression was used to model residents’ experiences of changing rainfall patterns, ocean surges, and flood events. An analysis of both compositional and contextual factors showed that there were urban communities where vulnerability to flooding tends to be clustered, and that this was not fully explained by the characteristics of the people of whom the community was composed. This study, thus, underscores the importance and complex nature of the interaction between personal and …

Mapping Landscape Values: Issues, Challenges And Lessons Learned From Field Work On The Olympic Peninsula, Washington, Diane Besser, Rebecca J. Mclain, Lee Cerveny, Kelly Biedenweg, David Banis

Geography Faculty Publications and Presentations

In order to inform natural resource policy and land management decisions, landscape values mapping (LVM) is increasingly used to collect data about the meanings that people attach to places and the activities associated with those places. This type of mapping provides geographically referenced data on areas of high density of values or associated with different types of values. This article focuses on issues and challenges that commonly occur in LVM, drawing on lessons learned in the US Forest Service Olympic Peninsula Human Ecology Mapping Project. The discussion covers choosing a spatial scale for collecting data, creating the base map, developing …

Relationships Between Environmental Governance And Water Quality In A Growing Metropolitan Area Of The Pacific Northwest, Usa, Heejun Chang, Paul R. Thiers, Noelwah R. Netusil, J. Alan Yeakley, Gretchen Rollwagen-Bollens, Steve Bollens, Sonia Singh

Geography Faculty Publications and Presentations

We investigate relationships between environmental governance and water quality in two adjacent growing metropolitan areas in the western US. While the Portland, Oregon and Vancouver, Washington metro areas share many common biophysical characteristics, they have different land development histories and water governance structures, providing a unique opportunity for examining how differences in governance might affect environmental quality. We conceptualize possible linkages in which water quality influences governance directly, using monitoring efforts as a metric, and indirectly by using the change in the sale price of single-family residential properties. Governance may then influence water quality directly through riparian restoration resulting from …

The Influence Of Recurrent Modes Of Climate Variability On The Occurrence Of Winter And Summer Extreme Temperatures Over North America, Paul C. Loikith, Anthony J. Broccoli

Geography Faculty Publications and Presentations

The influence of the Pacific–North American (PNA) pattern, the northern annular mode (NAM), and the El Ni~no–Southern Oscillation (ENSO) on extreme temperature days and months over North America is examined. Associations between extreme temperature days and months are strongest with the PNA and NAM andweaker for ENSO. In general, the associationwith extremes tends to be stronger onmonthly than daily time scales and for winter as compared to summer. Extreme temperatures are associated with the PNAandNAMin the vicinity of the centers of action of these circulation patterns; however, many extremes also occur on days when the amplitude and polarity of these …

Getting Salmon Back In Salmon Creek: Systematizing Comparative Water Quality Analysis For Targeted Restoration, Zbigniew J. Grabowski, Sarah Janjua, Michael Swamer, Heejun Chang, Eric Watson

Geography Faculty Publications and Presentations

This presentation focuses on water quality restoration efforts in Salmon Creek

Engaging Stakeholders In Ecosystem Service Assessment Under Climate Change And Urban Development Scenarios, Heejun Chang, David E. Ervin, Wes Hoyer, Mike Psaris, Ken Lyons, Emily D. Dietrich, Samantha Hamlin, John Lambrinos, Tammy Winfield, Bobby Cochran

Geography Faculty Publications and Presentations

This presentation focuses on how scientists can engage stakeholders in ecosystem service assessment.

Effects Of Runoff Sensitivity And Catchment Characteristics On Regional Actual Evapotranspiration Trends In The Conterminous Us, Il-Won Jung, Heejun Chang, John Risley

Geography Faculty Publications and Presentations

An understanding of the role of hydro-climatic and geographic regimes on regional actual evapotranspiration (AET) change is essential to improving our knowledge on predicting water availability in a changing climate. This study investigates the relationship between AET change for a 60 year period (1951–2010) and the runoff sensitivity in 255 undisturbed catchments over the US. The runoff sensitivity to climate change is simply defined as the relative magnitude between runoff and precipitation changes with time. Runoff sensitivity can readily explain the conflicting directions of AET changes under similar precipitation change. Under increasing precipitation, AET decreases when runoff is increasing more …