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Full-Text Articles in Glaciology
Late Pleistocene And Holocene Aged Glacial And Climatic Reconstructions In The Goat Rocks Wilderness, Washington, United States, Joshua Andrews Heard
Late Pleistocene And Holocene Aged Glacial And Climatic Reconstructions In The Goat Rocks Wilderness, Washington, United States, Joshua Andrews Heard
Dissertations and Theses
Eight glaciers, covering an area of 1.63 km2, reside on the northern and northeastern slopes of the Goat Rocks tallest peaks in the Cascades of central Washington. At least three glacial stands occurred downstream from these glaciers. Closest to modern glacier termini are Little Ice Age (LIA) moraines that were deposited between 1870 and 1899 AD, according to the lichenometric analysis. They are characterized by sharp, minimally eroded crests, little to no soil cover, and minimal vegetation cover. Glacier reconstructions indicate that LIA glaciers covered 8.29 km2, 76% more area than modern ice coverage. The average LIA equilibrium line altitude …
Characterization Of Firn Microstructure Using Scanning Electron Microscopy: Implications For Physical Properties Measurements And Climate Reconstructions, Nicole Spaulding
Characterization Of Firn Microstructure Using Scanning Electron Microscopy: Implications For Physical Properties Measurements And Climate Reconstructions, Nicole Spaulding
Electronic Theses and Dissertations
Samples from 12 East Antarctic firn and ice cores were analyzed using scanning electron micrcoscopy (SEM) in order to first develop a technique for the accurate characterization of physical properties and then to investigate the relationship between the physical microstructure and chemical properties. Both physical properties, such as grain size and porosity, and chemical properties, such as major ion and trace element concentration, provide information about atmospheric temperature changes, impurity content, accumulation rate and deformation history; therefore the characterization of both types of properties is necessary. Further, knowledge of the relationship between the physical and chemical properties may increase our …
Quantifying Twentieth Century Glacier Change In The Sierra Nevada, California, Hassan J. Basagic
Quantifying Twentieth Century Glacier Change In The Sierra Nevada, California, Hassan J. Basagic
Dissertations and Theses
Numerous small alpine glaciers occupy the high elevation regions of the central and southern Siena Nevada, California. These glaciers change size in response to variations in climate and are therefore important indicators of climate change. An inventory based on USGS topographic maps (l :24,000) revealed 1719 glaciers and perennial snow and ice features for a total area of 39.l5 ±7.52 km2. The number of 'true' glaciers, versus non-moving ice, is estimated to be 118, covering 15.87 ± 1.69 Km2. All glaciers were located on north to northeast aspects, at elevations >3000 m. Historical photographs, geologic evidence, …
Sources And Deposition Processes Linking Atmospheric Chemistry And Firn Records From Four Glacier Accumulation Zones In The Mcmurdo Dry Valleys, Antarctica, Bruce R. Williamson
Sources And Deposition Processes Linking Atmospheric Chemistry And Firn Records From Four Glacier Accumulation Zones In The Mcmurdo Dry Valleys, Antarctica, Bruce R. Williamson
Electronic Theses and Dissertations
Samples of snow and firn from accumulation zones on the Victoria Upper Glacier, the Clark Glacier, the Commonwealth Glacier and the Blue Glacier in the McMurdo Dry Valleys (~77 to 78º S and 161 to 164º E), Antarctica, are evaluated chemically and isotopically to determine the relative importance of local (site-specific) factors versus regional-scale climatic influences in defining regional glaciochemistry. Two approaches for distinguishing these controls are examined: comparing chemical concentrations using multivariate statistical analysis, and examining the effect of physical filtration (capturing particulate material largely originating in close proximity to each site) on sample values. These techniques provide constraints …