Social and Behavioral Sciences Commons^™

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 …

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 …

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) …

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 …

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 …