A Range Correction for Icesat and Its Potential Impact on Ice-sheet Mass Balance Studies
We report on a previously undocumented range error in NASA's Ice, Cloud and land Elevation Satellite (ICESat) that degrades elevation precision and introduces a small but significant elevation trend over the ICESat mission period. This range error (the Gaussian-Centroid or 'G-C'offset...
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ftnasantrs:oai:casi.ntrs.nasa.gov:20150000279 2023-05-15T16:40:35+02:00 A Range Correction for Icesat and Its Potential Impact on Ice-sheet Mass Balance Studies Brunt, Kelly M. Moholdt, G. Borsa, A. A. Fricker, H. A. Unclassified, Unlimited, Publicly available March 3, 2014 application/pdf http://hdl.handle.net/2060/20150000279 unknown Document ID: 20150000279 http://hdl.handle.net/2060/20150000279 Copyright, Distribution under U.S. Government purpose rights CASI Geosciences (General) GSFC-E-DAA-TN14754 The Cryosphere; 8; 2; 345-357 2014 ftnasantrs 2019-07-21T00:20:08Z We report on a previously undocumented range error in NASA's Ice, Cloud and land Elevation Satellite (ICESat) that degrades elevation precision and introduces a small but significant elevation trend over the ICESat mission period. This range error (the Gaussian-Centroid or 'G-C'offset) varies on a shot-to-shot basis and exhibits increasing scatter when laser transmit energies fall below 20 mJ. Although the G-C offset is uncorrelated over periods less than1 day, it evolves over the life of each of ICESat's three lasers in a series of ramps and jumps that give rise to spurious elevation trends of 0.92 to 1.90 cm yr(exp 1), depending on the time period considered. Using ICESat data over the Ross and Filchner-Ronne ice shelves we show that (1) the G-C offset introduces significant biases in ice-shelf mass balance estimates, and (2) the mass balance bias can vary between regions because of different temporal samplings of ICESat.We can reproduce the effect of the G-C offset over these two ice shelves by fitting trends to sample-weighted mean G-C offsets for each campaign, suggesting that it may not be necessary to fully repeat earlier ICESat studies to determine the impact of the G-C offset on ice-sheet mass balance estimates. Other/Unknown Material Ice Sheet Ice Shelf Ice Shelves NASA Technical Reports Server (NTRS) |
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Open Polar |
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NASA Technical Reports Server (NTRS) |
op_collection_id |
ftnasantrs |
language |
unknown |
topic |
Geosciences (General) |
spellingShingle |
Geosciences (General) Brunt, Kelly M. Moholdt, G. Borsa, A. A. Fricker, H. A. A Range Correction for Icesat and Its Potential Impact on Ice-sheet Mass Balance Studies |
topic_facet |
Geosciences (General) |
description |
We report on a previously undocumented range error in NASA's Ice, Cloud and land Elevation Satellite (ICESat) that degrades elevation precision and introduces a small but significant elevation trend over the ICESat mission period. This range error (the Gaussian-Centroid or 'G-C'offset) varies on a shot-to-shot basis and exhibits increasing scatter when laser transmit energies fall below 20 mJ. Although the G-C offset is uncorrelated over periods less than1 day, it evolves over the life of each of ICESat's three lasers in a series of ramps and jumps that give rise to spurious elevation trends of 0.92 to 1.90 cm yr(exp 1), depending on the time period considered. Using ICESat data over the Ross and Filchner-Ronne ice shelves we show that (1) the G-C offset introduces significant biases in ice-shelf mass balance estimates, and (2) the mass balance bias can vary between regions because of different temporal samplings of ICESat.We can reproduce the effect of the G-C offset over these two ice shelves by fitting trends to sample-weighted mean G-C offsets for each campaign, suggesting that it may not be necessary to fully repeat earlier ICESat studies to determine the impact of the G-C offset on ice-sheet mass balance estimates. |
format |
Other/Unknown Material |
author |
Brunt, Kelly M. Moholdt, G. Borsa, A. A. Fricker, H. A. |
author_facet |
Brunt, Kelly M. Moholdt, G. Borsa, A. A. Fricker, H. A. |
author_sort |
Brunt, Kelly M. |
title |
A Range Correction for Icesat and Its Potential Impact on Ice-sheet Mass Balance Studies |
title_short |
A Range Correction for Icesat and Its Potential Impact on Ice-sheet Mass Balance Studies |
title_full |
A Range Correction for Icesat and Its Potential Impact on Ice-sheet Mass Balance Studies |
title_fullStr |
A Range Correction for Icesat and Its Potential Impact on Ice-sheet Mass Balance Studies |
title_full_unstemmed |
A Range Correction for Icesat and Its Potential Impact on Ice-sheet Mass Balance Studies |
title_sort |
range correction for icesat and its potential impact on ice-sheet mass balance studies |
publishDate |
2014 |
url |
http://hdl.handle.net/2060/20150000279 |
op_coverage |
Unclassified, Unlimited, Publicly available |
genre |
Ice Sheet Ice Shelf Ice Shelves |
genre_facet |
Ice Sheet Ice Shelf Ice Shelves |
op_source |
CASI |
op_relation |
Document ID: 20150000279 http://hdl.handle.net/2060/20150000279 |
op_rights |
Copyright, Distribution under U.S. Government purpose rights |
_version_ |
1766030993595039744 |