Greenland Glacier Albedo Variability
The program for Arctic Regional Climate Assessment (PARCA) is a NASA-funded project with the prime goal of addressing the mass balance of the Greenland ice sheet. Since the formal initiation of the program in 1995, there has been a significant improvement in the estimates of the mass balance of the...
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ftnasantrs:oai:casi.ntrs.nasa.gov:20040050637 2023-05-15T13:10:47+02:00 Greenland Glacier Albedo Variability Unclassified, Unlimited, Publicly available [2004] application/pdf http://hdl.handle.net/2060/20040050637 unknown Document ID: 20040050637 http://hdl.handle.net/2060/20040050637 No Copyright CASI Meteorology and Climatology 2004 ftnasantrs 2019-07-21T07:43:04Z The program for Arctic Regional Climate Assessment (PARCA) is a NASA-funded project with the prime goal of addressing the mass balance of the Greenland ice sheet. Since the formal initiation of the program in 1995, there has been a significant improvement in the estimates of the mass balance of the ice sheet. Results from this program reveal that the high-elevation regions of the ice sheet are approximately in balance, but the margins are thinning. Laser surveys reveal significant thinning along 70 percent of the ice sheet periphery below 2000 m elevations, and in at least one outlet glacier, Kangerdlugssuaq in southeast Greenland, thinning has been as much as 10 m/yr. This study examines the albedo variability in four outlet glaciers to help separate out the relative contributions of surface melting versus ice dynamics to the recent mass balance changes. Analysis of AVHRR Polar Pathfinder albedo shows that at the Petermann and Jakobshavn glaciers, there has been a negative trend in albedo at the glacier terminus from 1981 to 2000, whereas the Stor+strommen and Kangerdlugssuaq glaciers show slightly positive trends in albedo. These findings are consistent with recent observations of melt extent from passive microwave data which show more melt on the western side of Greenland and slightly less on the eastern side. Significance of albedo trends will depend on where and when the albedo changes occur. Since the majority of surface melt occurs in the shallow sloping western margin of the ice sheet where the shortwave radiation dominates the energy balance in summer (e.g. Jakobshavn region) this region will be more sensitive to changes in albedo than in regions where this is not the case. Near the Jakobshavn glacier, even larger changes in albedo have been observed, with decreases as much as 20 percent per decade. Other/Unknown Material albedo Arctic Arctic Regional Climate Assessment glacier Greenland Ice Sheet Jakobshavn PARCA Program for Arctic Regional Climate Assessment NASA Technical Reports Server (NTRS) Arctic Greenland |
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Open Polar |
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NASA Technical Reports Server (NTRS) |
op_collection_id |
ftnasantrs |
language |
unknown |
topic |
Meteorology and Climatology |
spellingShingle |
Meteorology and Climatology Greenland Glacier Albedo Variability |
topic_facet |
Meteorology and Climatology |
description |
The program for Arctic Regional Climate Assessment (PARCA) is a NASA-funded project with the prime goal of addressing the mass balance of the Greenland ice sheet. Since the formal initiation of the program in 1995, there has been a significant improvement in the estimates of the mass balance of the ice sheet. Results from this program reveal that the high-elevation regions of the ice sheet are approximately in balance, but the margins are thinning. Laser surveys reveal significant thinning along 70 percent of the ice sheet periphery below 2000 m elevations, and in at least one outlet glacier, Kangerdlugssuaq in southeast Greenland, thinning has been as much as 10 m/yr. This study examines the albedo variability in four outlet glaciers to help separate out the relative contributions of surface melting versus ice dynamics to the recent mass balance changes. Analysis of AVHRR Polar Pathfinder albedo shows that at the Petermann and Jakobshavn glaciers, there has been a negative trend in albedo at the glacier terminus from 1981 to 2000, whereas the Stor+strommen and Kangerdlugssuaq glaciers show slightly positive trends in albedo. These findings are consistent with recent observations of melt extent from passive microwave data which show more melt on the western side of Greenland and slightly less on the eastern side. Significance of albedo trends will depend on where and when the albedo changes occur. Since the majority of surface melt occurs in the shallow sloping western margin of the ice sheet where the shortwave radiation dominates the energy balance in summer (e.g. Jakobshavn region) this region will be more sensitive to changes in albedo than in regions where this is not the case. Near the Jakobshavn glacier, even larger changes in albedo have been observed, with decreases as much as 20 percent per decade. |
title |
Greenland Glacier Albedo Variability |
title_short |
Greenland Glacier Albedo Variability |
title_full |
Greenland Glacier Albedo Variability |
title_fullStr |
Greenland Glacier Albedo Variability |
title_full_unstemmed |
Greenland Glacier Albedo Variability |
title_sort |
greenland glacier albedo variability |
publishDate |
2004 |
url |
http://hdl.handle.net/2060/20040050637 |
op_coverage |
Unclassified, Unlimited, Publicly available |
geographic |
Arctic Greenland |
geographic_facet |
Arctic Greenland |
genre |
albedo Arctic Arctic Regional Climate Assessment glacier Greenland Ice Sheet Jakobshavn PARCA Program for Arctic Regional Climate Assessment |
genre_facet |
albedo Arctic Arctic Regional Climate Assessment glacier Greenland Ice Sheet Jakobshavn PARCA Program for Arctic Regional Climate Assessment |
op_source |
CASI |
op_relation |
Document ID: 20040050637 http://hdl.handle.net/2060/20040050637 |
op_rights |
No Copyright |
_version_ |
1766242243233972224 |