Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 8 of 8

Full-Text Articles in Entire DC Network

A Mass Balance Study Of The West Antarctic Ice Sheet, Vandy Blue Spikes Dec 2003

A Mass Balance Study Of The West Antarctic Ice Sheet, Vandy Blue Spikes

Electronic Theses and Dissertations

The present state of the West Antarctic ice sheet (WAIS) is a prime concern of science, but its large size and remote location have limited the amount of reliable data that are available for mass balance calculations. The spatial pattern of mass balance for a 100-km2 portion of the WAIS is estimated by calculating the residual flux of ice through 1-km grid cells organized into a geographical information system (GIs). The input data used for this estimate include continent-scale compilations of ice thickness and snow accumulation rate measurements, and ground-based measurements of snow accumulation rate and ice velocity. The ...


The Characteristics That Control The Stability Of Eroding Coastal Bluffs In Maine, Corinn C. Keblinsky Aug 2003

The Characteristics That Control The Stability Of Eroding Coastal Bluffs In Maine, Corinn C. Keblinsky

Electronic Theses and Dissertations

Bluffs of glacigenic sediment exist along 53% of the tidal shoreline of Maine. Under the current regime of rising sea level, waves, groundwater, and sub-aerial processes easily erode these materials. The hazardous nature of the bluffs is not widely recognized by the public, and new homeowners are often shocked to find out that their property is disappearing. To better educate the public, the Maine Geological Survey is mapping the stability of coastal bluffs. This report utilizes that database along with other available data to determine what controls the relative stability of bluffs. A geographic information system (GIs) was used to ...


An Interhemispheric Comparison Of The Recession Of Mountain Glaciers In The Last 150 Years, Colby Smith Jan 2003

An Interhemispheric Comparison Of The Recession Of Mountain Glaciers In The Last 150 Years, Colby Smith

Electronic Theses and Dissertations

Historical records in the Northern Hemisphere show overall glacier retreat since about AD 1860-1890. A glacial retreat of similar timing and magnitude in the Southern Hemisphere is less well established. Comparison of the timing and magnitude of glacial recession in the two polar hemispheres over the past century can elucidate mechanisms driving global climatic change. In order to determine the recession patterns of Murchison, Hooker, and Tasman Glaciers in the Southern Alps of New Zealand, geomorphic maps were constructed and recent glacial deposits were dated using lichenometry. Since the mid-to-late nineteenth century, each glacier terminus has retreated about 1.5 ...


Stable Sulfur Isotope Rations From West Antarctica And The Tien Shan Mountains: Sulfur Cycle Characteristics From Two Environmentally Distinct Areas, Lee Pruett Jan 2003

Stable Sulfur Isotope Rations From West Antarctica And The Tien Shan Mountains: Sulfur Cycle Characteristics From Two Environmentally Distinct Areas, Lee Pruett

Electronic Theses and Dissertations

Continuous snow pit and ice core samples from two distinct environments (West Antarctica and the Tien Shan mountains in central Asia) were analyzed for 6 3 4 ~ and used to assess different regional sulfur cycle characteristics. In West Antarctica, 18 continuous samples were obtained from the RIDSA ice core (78.73"S, 116.33"W, 1740 m asl), covering the years 1935 to 1976. Each sample represents from 2 to 3 years of snow deposition, and the combination of summer and winter seasons varies by sample. 6 3 4 ~ values range from 3.1 %O to 9.9%0, and ...


Design, Implementation And Assessment Of An Earth Systems Science Course For Secondary Teachers, Jeffery C. Owen Jan 2003

Design, Implementation And Assessment Of An Earth Systems Science Course For Secondary Teachers, Jeffery C. Owen

Electronic Theses and Dissertations

In the fall of 2002 the Department of Earth Sciences at the University of Maine piloted an innovative course developed as a core offering for the new Master of Science in Teaching program. A team of four instructors comprised of two Earth Sciences faculty and two science educators developed the course and implemented it with nine students- six in-service teachers and three pre-service teachers. The course addressed multiple needs of secondary teachers through the integration of instruction in curriculum design, pedagogy, assessment, and classroom-level educational research, and earth systems science content. The components of instruction taught in the course included ...


Crevassing And Calving Of Glacial Ice, James Patrick Kenneally Jan 2003

Crevassing And Calving Of Glacial Ice, James Patrick Kenneally

Electronic Theses and Dissertations

Calving of ice is a relatively new area of research in the still young field of glaciology. In the short time that calving has been studied, it has been mainly treated as an afterthought, with the predominant mode of thinking being that it will happen so to concern oneself with why is not important. Many studies dealt with observations of calving front positions over time vs. ice velocity in an attempt to quantify the calving rate as the difference between the two, while others have attempted to deduce some empirical relationship between calving rate and variables such as water depth ...


Soil Solution Dynamics In Response To Elevated Nitrogen And Sulfur Treatments At The Bear Brook Watershed In Maine, Johanna Szillery Jan 2003

Soil Solution Dynamics In Response To Elevated Nitrogen And Sulfur Treatments At The Bear Brook Watershed In Maine, Johanna Szillery

Electronic Theses and Dissertations

Base cation depletion in forest soils of northeastern North America is a continuing concern because of the ongoing elevated deposition of sulfur (S) and nitrogen (N), intensive-management practices, and the often poorly understood implications of land-use history on modem ecosystem function. At the Bear Brook Watershed in Maine (BBWM), one of two paired, forested watersheds has been subjected to experimental additions of S and N for over a decade. Treatments consist of 28.8 kg S ha-' yr-' and 25.2 kg N ha-' yr-' in the form of granular (NH&SO4 applied bimonthly by helicopter. Ceramic cup tension lysimeters ...


12,000-Year Record Of Lake-Level And Vegetative Change At Mathews Pond, Piscataquis County, Maine, Usa, Andrea Masterman Nurse Jan 2003

12,000-Year Record Of Lake-Level And Vegetative Change At Mathews Pond, Piscataquis County, Maine, Usa, Andrea Masterman Nurse

Electronic Theses and Dissertations

This study of late-glacial and Holocene changes in lake-level and vegetation at Mathews Pond contributes new information about Holocene environments in northeastern North America. The research establishes a 12,000-year record of paleohydrology for the watershed adjacent to Big Reed Forest Reserve, the largest stand of old-growth forest in the northeastern United States. Mathews Pond is a 7.4 ha, closed-basin, groundwaterseepage lake located in an upland, forested region of the Aroostook River drainage system. Glacial meltwater briefly filled the basin - 13.0 ka (1 ka = 1000 I4C yr BP)). The lake existed as a shallow pool in the deep ...