Investigating the interior of West Antarctica with light, radar, and electrical conductance
Thesis (Ph.D.)--University of Washington, 2013 Ice sheets play an important role in both the modern climate and in past variations of Earth's history. Our understanding of ice sheets has been limited by few observations until recent advances in technology, notably air planes and satellites, whi...
Main Author: | |
---|---|
Other Authors: | |
Format: | Thesis |
Language: | English |
Published: |
2013
|
Subjects: | |
Online Access: | http://hdl.handle.net/1773/25011 |
id |
ftunivwashington:oai:digital.lib.washington.edu:1773/25011 |
---|---|
record_format |
openpolar |
spelling |
ftunivwashington:oai:digital.lib.washington.edu:1773/25011 2023-05-15T13:43:39+02:00 Investigating the interior of West Antarctica with light, radar, and electrical conductance Fudge, Tyler Jeffrey Waddington, Edwin D 2013 application/pdf http://hdl.handle.net/1773/25011 en_US eng Fudge_washington_0250E_12539.pdf http://hdl.handle.net/1773/25011 Copyright is held by the individual authors. Climate Change Ice Core Ice Sheet Paleoclimate Geophysics earth and space sciences Thesis 2013 ftunivwashington 2023-03-12T18:51:11Z Thesis (Ph.D.)--University of Washington, 2013 Ice sheets play an important role in both the modern climate and in past variations of Earth's history. Our understanding of ice sheets has been limited by few observations until recent advances in technology, notably air planes and satellites, which have allowed increasingly more detailed investigations. Here I focus on using the internal structure of ice sheets to place modern observations in context. This is done with a variety of tools. First, I investigated the ability of borehole camera measurements to recover information about the physical properties of firn. I found that a measurement with a single wavelength of light was not capable of differentiating between brightness variations due to changes in grain size and changes in density. An additional measurement in the near infrared, which is sensitive to grain size variations, was identified as a way to differentiate density variations from grain size variations. I also use the internal structure of the ice sheet imaged using ice penetrating radar to examine the past flow structure of a major outlet glacier of West Antarctica. The flow directions were found to have not changed significantly in the past few hundred years and the analysis also revealed that the satellite-derived velocities had uncertainties larger than reported. The internal structure of an ice sheet can also be investigated by drilling an ice core. By obtaining samples of ancient ice, many detailed measurements are possible to look at past variations in climate and ice sheet behavior. I measured the electrical properties of the WAIS Divide ice core and was able to identify an annual signal to a depth of 2800. I then developed the first annually resolved timescale from the Southern Hemisphere that spanned into the last glacial period, 30 ka. The annual timescale allowed identification of accumulation-rate changes not resolvable in other Antarctic ice cores. The timescale and accumulation-rate history were combined with the water stable ... Thesis Antarc* Antarctic Antarctica ice core Ice Sheet West Antarctica University of Washington, Seattle: ResearchWorks Antarctic West Antarctica |
institution |
Open Polar |
collection |
University of Washington, Seattle: ResearchWorks |
op_collection_id |
ftunivwashington |
language |
English |
topic |
Climate Change Ice Core Ice Sheet Paleoclimate Geophysics earth and space sciences |
spellingShingle |
Climate Change Ice Core Ice Sheet Paleoclimate Geophysics earth and space sciences Fudge, Tyler Jeffrey Investigating the interior of West Antarctica with light, radar, and electrical conductance |
topic_facet |
Climate Change Ice Core Ice Sheet Paleoclimate Geophysics earth and space sciences |
description |
Thesis (Ph.D.)--University of Washington, 2013 Ice sheets play an important role in both the modern climate and in past variations of Earth's history. Our understanding of ice sheets has been limited by few observations until recent advances in technology, notably air planes and satellites, which have allowed increasingly more detailed investigations. Here I focus on using the internal structure of ice sheets to place modern observations in context. This is done with a variety of tools. First, I investigated the ability of borehole camera measurements to recover information about the physical properties of firn. I found that a measurement with a single wavelength of light was not capable of differentiating between brightness variations due to changes in grain size and changes in density. An additional measurement in the near infrared, which is sensitive to grain size variations, was identified as a way to differentiate density variations from grain size variations. I also use the internal structure of the ice sheet imaged using ice penetrating radar to examine the past flow structure of a major outlet glacier of West Antarctica. The flow directions were found to have not changed significantly in the past few hundred years and the analysis also revealed that the satellite-derived velocities had uncertainties larger than reported. The internal structure of an ice sheet can also be investigated by drilling an ice core. By obtaining samples of ancient ice, many detailed measurements are possible to look at past variations in climate and ice sheet behavior. I measured the electrical properties of the WAIS Divide ice core and was able to identify an annual signal to a depth of 2800. I then developed the first annually resolved timescale from the Southern Hemisphere that spanned into the last glacial period, 30 ka. The annual timescale allowed identification of accumulation-rate changes not resolvable in other Antarctic ice cores. The timescale and accumulation-rate history were combined with the water stable ... |
author2 |
Waddington, Edwin D |
format |
Thesis |
author |
Fudge, Tyler Jeffrey |
author_facet |
Fudge, Tyler Jeffrey |
author_sort |
Fudge, Tyler Jeffrey |
title |
Investigating the interior of West Antarctica with light, radar, and electrical conductance |
title_short |
Investigating the interior of West Antarctica with light, radar, and electrical conductance |
title_full |
Investigating the interior of West Antarctica with light, radar, and electrical conductance |
title_fullStr |
Investigating the interior of West Antarctica with light, radar, and electrical conductance |
title_full_unstemmed |
Investigating the interior of West Antarctica with light, radar, and electrical conductance |
title_sort |
investigating the interior of west antarctica with light, radar, and electrical conductance |
publishDate |
2013 |
url |
http://hdl.handle.net/1773/25011 |
geographic |
Antarctic West Antarctica |
geographic_facet |
Antarctic West Antarctica |
genre |
Antarc* Antarctic Antarctica ice core Ice Sheet West Antarctica |
genre_facet |
Antarc* Antarctic Antarctica ice core Ice Sheet West Antarctica |
op_relation |
Fudge_washington_0250E_12539.pdf http://hdl.handle.net/1773/25011 |
op_rights |
Copyright is held by the individual authors. |
_version_ |
1766191590781485056 |