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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.

Unique dynamic behaviors of ice divides : Siple Dome and the rheological properties of ice /

Pettit, Erin Christine. January 2003 (has links)
Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (p. 153-163).

The flow history of Siple Dome and Ice Streams C and D, West Antarctica : inferences from geophysical measurements and ice flow models /

Nereson, Nadine A. January 1998 (has links)
Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (p. [182]-192).

Integration of higher-order physics in the community ice sheet model scientific and software concerns /

Bocek, Timothy Joseph. January 2009 (has links)
Thesis (MS)--University of Montana, 2009. / Contents viewed on December 19, 2009. Title from author supplied metadata. Includes bibliographical references.

Estimation of ice-sheet topography and motion using interferometric synthetic aperture radar /

Joughin, Ian. January 1995 (has links)
Thesis (Ph. D.)--University of Washington, 1995. / Vita. Includes bibliographical references (leaves [177]-182).

Characterization of the small scale ice sheet topography of Antarctica and Greenland /

Smith, Benjamin E. January 2005 (has links)
Thesis (Ph. D.)--University of Washington, 2005. / Vita. Includes bibliographical references (p. 98-104).

Analysis of Spatial and Temporal Variations in Strain Rates Near Swiss Camp, Greenland

Rumrill, Julie 13 February 2009 (has links)
In this thesis, I present results from a two-year study of strain-rate variations along a flow line on the western margin of the Greenland ice sheet. I used baseline network solutions to investigate variations in longitudinal strain rates over the 2006 and 2007 melt seasons. Analyses revealed high-magnitude, short-duration events of increased longitudinal strain early in the melt season coincident with a high melt year, suggesting a link between melt production and its effects on seasonal ice flow. Results from 2006 data show that longitudinal strain rates became variable shortly after the onset of melt (day 186) changing up to ~ 15 x 10-4 a-1 within 24 hours. The onset of melting occurred earlier in 2007 (day 153) and was also followed closely by strain-rate deviation from background rates calculated prior to melting. The data revealed rapid (hours to days), high-magnitude (two to ten times greater than background rates) changes in longitudinal strain rates (hereafter referred to as ‘high-strain’ events) that occurred both on the small-scale (affecting 1-4 baselines) and on the large-scale (affecting 5 or more baselines). Large-scale high-strain events were infrequent, on the order of two events per season. Events were likely caused by drainage of supraglacial meltwater that penetrated to the bed of the glacier raising the basal water pressure. The increase in pressure reduced the basal resistive stress, and allowed rapid local acceleration. The basal stress reduction was transmitted to areas of higher stress which resulted in longitudinal compression of the ice down glacier and longitudinal extension up glacier. The evolution of high-strain events altered longitudinal strain rates more than 15 km along flow from the site of initiation. I estimated the origin and spatial extent of highstrain events by assessing the magnitude of the strain-rate variations in various baselines, and observing whether the altered strain regime was extensive or compressive. Magnitude and timing of changes in strain suggest that high-strain events originated in the ablation zone, the equilibrium zone, and inland of the equilibrium zone, and indicate that short-term altered stress conditions are not confined to the ablation zone. The background strain-rate for 2007 (~ -7 x 10-4 a-1 for a 37 km longitudinal baseline) was similar to the 2006 longitudinal background rate. When extrapolating the 2006 background rate over the melt season, the expected change in baseline length (~ 11 m) was similar to the observed change (~ 9 m). In contrast, when extrapolating the 2007 background rate over the melt season, the expected shortening was ~ 6 m, but the observed shortening was less than 1 m. This result suggests that seasonal high-strain events have the ability to alter longitudinal baseline length, allowing a greater ice flux to lower elevations where melting occurs for a larger portion of the year. However, the cumulative seasonal effects of both large-scale and small-scale strain events are modest, and indicate that seasonal changes in strain rates have a minor effect on the overall stability of the ice sheet. Nevertheless, it is possible that over much longer timescales these seasonal changes may become more important with increasing temperatures and available melt. Results from this study may also be useful in making broader inferences regarding the response of grounded portions of the ice sheet to seasonal changes in basal resistive stress.

Decadal mass balance of the Antarctic ice sheet from satellite radar altimetry and its contribution

Li, Yonghong. January 2006 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on April 29, 2009) Vita. Includes bibliographical references.

Ice stream dynamics : a transition between sheet flow and shelf flow /

Hofstede, Coen Matthijs, January 2008 (has links)
Thesis (Ph.D.) in Earth Sciences--University of Maine, 2008. / Includes vita. Includes bibliographical references (leaves 125-128).

Cosmogenic ¹⁰Be chronology for the last deglaciation of the southern Scandinavian Ice Sheet /

Rinterknecht, Vincent R. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2004. / Printout. Includes bibliographical references. Also available online.

Meltwater infilltration [sic] in the accumulation zone, West Greenland Ice Sheet

Sturgis, Daniel J. January 2009 (has links)
Thesis (M.S.)--University of Wyoming, 2009. / Title from PDF title page (viewed on June 16, 2010). Includes bibliographical references (p. 61-64).

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