Greenland Ice Sheet Mass Balance: Distribution of Increased Mass Loss with Climate Warming; 2003-07 Versus 1992-2002
We derive mass changes of the Greenland ice sheet (GIS) for 2003-07 from ICESat laser altimetry and compare them with results for 1992-2002 from ERS radar and airborne laser altimetry. The GIS continued to grow inland and thin at the margins during 2003 07, but surface melting and accelerated flow s...
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ftnasantrs:oai:casi.ntrs.nasa.gov:20120010516 2023-05-15T16:28:39+02:00 Greenland Ice Sheet Mass Balance: Distribution of Increased Mass Loss with Climate Warming; 2003-07 Versus 1992-2002 Li, Jun Benner, Anita C. Cornejo, Helen G. Neumann, Thomas A. Saba, Jack L. Wang, Weili DiMarzio, John Giovinetto, Mario B. Beckley, Matthew Yi, Donghui Robbins, John Zwally, H. Jay Unclassified, Unlimited, Publicly available 2011 application/pdf http://hdl.handle.net/2060/20120010516 unknown Document ID: 20120010516 http://hdl.handle.net/2060/20120010516 Copyright, Distribution as joint owner in the copyright CASI Meteorology and Climatology GSFC.JA.00327.2012 Journal of Glaciology (ISSN 0022-1430); 57; 201; 88-102 2011 ftnasantrs 2019-07-21T00:49:55Z We derive mass changes of the Greenland ice sheet (GIS) for 2003-07 from ICESat laser altimetry and compare them with results for 1992-2002 from ERS radar and airborne laser altimetry. The GIS continued to grow inland and thin at the margins during 2003 07, but surface melting and accelerated flow significantly increased the marginal thinning compared with the 1990s. The net balance changed from a small loss of 7 plus or minus 3 Gt a 1(sup -1) in the 1990s to 171 plus or minus 4 Gt a (sup -1) for 2003-07, contributing 0.5 mm a(sup -1) to recent global sea-level rise. We divide the derived mass changes into two components: (1) from changes in melting and ice dynamics and (2) from changes in precipitation and accumulation rate. We use our firn compaction model to calculate the elevation changes driven by changes in both temperature and accumulation rate and to calculate the appropriate density to convert the accumulation-driven changes to mass changes. Increased losses from melting and ice dynamics (17-206 Gt a(sup-1) are over seven times larger than increased gains from precipitation (10 35 Gt a(sup-1) during a warming period of approximately 2 K (10 a)(sup -1) over the GIS. Above 2000m elevation, the rate of gain decreased from 44 to 28 Gt a(sup-1), while below 2000m the rate of loss increased from 51 to 198 Gt a(sup-1). Enhanced thinning below the equilibrium line on outlet glaciers indicates that increased melting has a significant impact on outlet glaciers, as well as accelerating ice flow. Increased thinning at higher elevations appears to be induced by dynamic coupling to thinning at the margins on decadal timescales. Other/Unknown Material Greenland Ice Sheet NASA Technical Reports Server (NTRS) Greenland |
institution |
Open Polar |
collection |
NASA Technical Reports Server (NTRS) |
op_collection_id |
ftnasantrs |
language |
unknown |
topic |
Meteorology and Climatology |
spellingShingle |
Meteorology and Climatology Li, Jun Benner, Anita C. Cornejo, Helen G. Neumann, Thomas A. Saba, Jack L. Wang, Weili DiMarzio, John Giovinetto, Mario B. Beckley, Matthew Yi, Donghui Robbins, John Zwally, H. Jay Greenland Ice Sheet Mass Balance: Distribution of Increased Mass Loss with Climate Warming; 2003-07 Versus 1992-2002 |
topic_facet |
Meteorology and Climatology |
description |
We derive mass changes of the Greenland ice sheet (GIS) for 2003-07 from ICESat laser altimetry and compare them with results for 1992-2002 from ERS radar and airborne laser altimetry. The GIS continued to grow inland and thin at the margins during 2003 07, but surface melting and accelerated flow significantly increased the marginal thinning compared with the 1990s. The net balance changed from a small loss of 7 plus or minus 3 Gt a 1(sup -1) in the 1990s to 171 plus or minus 4 Gt a (sup -1) for 2003-07, contributing 0.5 mm a(sup -1) to recent global sea-level rise. We divide the derived mass changes into two components: (1) from changes in melting and ice dynamics and (2) from changes in precipitation and accumulation rate. We use our firn compaction model to calculate the elevation changes driven by changes in both temperature and accumulation rate and to calculate the appropriate density to convert the accumulation-driven changes to mass changes. Increased losses from melting and ice dynamics (17-206 Gt a(sup-1) are over seven times larger than increased gains from precipitation (10 35 Gt a(sup-1) during a warming period of approximately 2 K (10 a)(sup -1) over the GIS. Above 2000m elevation, the rate of gain decreased from 44 to 28 Gt a(sup-1), while below 2000m the rate of loss increased from 51 to 198 Gt a(sup-1). Enhanced thinning below the equilibrium line on outlet glaciers indicates that increased melting has a significant impact on outlet glaciers, as well as accelerating ice flow. Increased thinning at higher elevations appears to be induced by dynamic coupling to thinning at the margins on decadal timescales. |
format |
Other/Unknown Material |
author |
Li, Jun Benner, Anita C. Cornejo, Helen G. Neumann, Thomas A. Saba, Jack L. Wang, Weili DiMarzio, John Giovinetto, Mario B. Beckley, Matthew Yi, Donghui Robbins, John Zwally, H. Jay |
author_facet |
Li, Jun Benner, Anita C. Cornejo, Helen G. Neumann, Thomas A. Saba, Jack L. Wang, Weili DiMarzio, John Giovinetto, Mario B. Beckley, Matthew Yi, Donghui Robbins, John Zwally, H. Jay |
author_sort |
Li, Jun |
title |
Greenland Ice Sheet Mass Balance: Distribution of Increased Mass Loss with Climate Warming; 2003-07 Versus 1992-2002 |
title_short |
Greenland Ice Sheet Mass Balance: Distribution of Increased Mass Loss with Climate Warming; 2003-07 Versus 1992-2002 |
title_full |
Greenland Ice Sheet Mass Balance: Distribution of Increased Mass Loss with Climate Warming; 2003-07 Versus 1992-2002 |
title_fullStr |
Greenland Ice Sheet Mass Balance: Distribution of Increased Mass Loss with Climate Warming; 2003-07 Versus 1992-2002 |
title_full_unstemmed |
Greenland Ice Sheet Mass Balance: Distribution of Increased Mass Loss with Climate Warming; 2003-07 Versus 1992-2002 |
title_sort |
greenland ice sheet mass balance: distribution of increased mass loss with climate warming; 2003-07 versus 1992-2002 |
publishDate |
2011 |
url |
http://hdl.handle.net/2060/20120010516 |
op_coverage |
Unclassified, Unlimited, Publicly available |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Ice Sheet |
genre_facet |
Greenland Ice Sheet |
op_source |
CASI |
op_relation |
Document ID: 20120010516 http://hdl.handle.net/2060/20120010516 |
op_rights |
Copyright, Distribution as joint owner in the copyright |
_version_ |
1766018317340901376 |