Changes in the firn structure of the western Greenland Ice Sheet caused by recent warming
peer reviewed Atmospheric warming over the Greenland Ice Sheet during the last 2 decades has increased the amount of surface meltwater production, resulting in the migration of melt and percolation regimes to higher altitudes and an increase in the amount of ice content from refrozen meltwater found...
Published in: | The Cryosphere |
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Format: | Article in Journal/Newspaper |
Language: | English |
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Copernicus GmbH
2015
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Online Access: | https://orbi.uliege.be/handle/2268/301890 https://orbi.uliege.be/bitstream/2268/301890/1/Pena_TC_2015.pdf https://doi.org/10.5194/tc-9-1203-2015 |
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ftorbi:oai:orbi.ulg.ac.be:2268/301890 2024-04-21T08:03:12+00:00 Changes in the firn structure of the western Greenland Ice Sheet caused by recent warming De La Peña, S. Howat, I.M. Nienow, P.W. Van Den Broeke, M.R. Mosley-Thompson, E. Price, S.F. Mair, D. Noël, Brice Sole, A.J. 2015-06-11 https://orbi.uliege.be/handle/2268/301890 https://orbi.uliege.be/bitstream/2268/301890/1/Pena_TC_2015.pdf https://doi.org/10.5194/tc-9-1203-2015 en eng Copernicus GmbH https://tc.copernicus.org/articles/9/1203/2015/tc-9-1203-2015.pdf urn:issn:1994-0416 urn:issn:1994-0424 https://orbi.uliege.be/handle/2268/301890 info:hdl:2268/301890 https://orbi.uliege.be/bitstream/2268/301890/1/Pena_TC_2015.pdf doi:10.5194/tc-9-1203-2015 scopus-id:2-s2.0-84937161463 open access http://purl.org/coar/access_right/c_abf2 info:eu-repo/semantics/openAccess The Cryosphere, 9 (3), 1203 - 1211 (2015-06-11) Water Science and Technology Earth-Surface Processes Physical chemical mathematical & earth Sciences Earth sciences & physical geography Physique chimie mathématiques & sciences de la terre Sciences de la terre & géographie physique journal article http://purl.org/coar/resource_type/c_6501 info:eu-repo/semantics/article peer reviewed 2015 ftorbi https://doi.org/10.5194/tc-9-1203-2015 2024-03-27T14:58:15Z peer reviewed Atmospheric warming over the Greenland Ice Sheet during the last 2 decades has increased the amount of surface meltwater production, resulting in the migration of melt and percolation regimes to higher altitudes and an increase in the amount of ice content from refrozen meltwater found in the firn above the superimposed ice zone. Here we present field and airborne radar observations of buried ice layers within the near-surface (0-20 m) firn in western Greenland, obtained from campaigns between 1998 and 2014. We find a sharp increase in firn-ice content in the form of thick widespread layers in the percolation zone, which decreases the capacity of the firn to store meltwater. The estimated total annual ice content retained in the near-surface firn in areas with positive surface mass balance west of the ice divide in Greenland reached a maximum of 74 ± 25 Gt in 2012, compared to the 1958-1999 average of 13 ± 2 Gt, while the percolation zone area more than doubled between 2003 and 2012. Increased melt and column densification resulted in surface lowering averaging -0.80 ± 0.39 m yr-1 between 1800 and 2800 m in the accumulation zone of western Greenland. Since 2007, modeled annual melt and refreezing rates in the percolation zone at elevations below 2100 m surpass the annual snowfall from the previous year, implying that mass gain in the region is retained after melt in the form of refrozen meltwater. If current melt trends over high elevation regions continue, subsequent changes in firn structure will have implications for the hydrology of the ice sheet and related abrupt seasonal densification could become increasingly significant for altimetry-derived ice sheet mass balance estimates. Article in Journal/Newspaper Greenland Ice Sheet The Cryosphere University of Liège: ORBi (Open Repository and Bibliography) The Cryosphere 9 3 1203 1211 |
institution |
Open Polar |
collection |
University of Liège: ORBi (Open Repository and Bibliography) |
op_collection_id |
ftorbi |
language |
English |
topic |
Water Science and Technology Earth-Surface Processes Physical chemical mathematical & earth Sciences Earth sciences & physical geography Physique chimie mathématiques & sciences de la terre Sciences de la terre & géographie physique |
spellingShingle |
Water Science and Technology Earth-Surface Processes Physical chemical mathematical & earth Sciences Earth sciences & physical geography Physique chimie mathématiques & sciences de la terre Sciences de la terre & géographie physique De La Peña, S. Howat, I.M. Nienow, P.W. Van Den Broeke, M.R. Mosley-Thompson, E. Price, S.F. Mair, D. Noël, Brice Sole, A.J. Changes in the firn structure of the western Greenland Ice Sheet caused by recent warming |
topic_facet |
Water Science and Technology Earth-Surface Processes Physical chemical mathematical & earth Sciences Earth sciences & physical geography Physique chimie mathématiques & sciences de la terre Sciences de la terre & géographie physique |
description |
peer reviewed Atmospheric warming over the Greenland Ice Sheet during the last 2 decades has increased the amount of surface meltwater production, resulting in the migration of melt and percolation regimes to higher altitudes and an increase in the amount of ice content from refrozen meltwater found in the firn above the superimposed ice zone. Here we present field and airborne radar observations of buried ice layers within the near-surface (0-20 m) firn in western Greenland, obtained from campaigns between 1998 and 2014. We find a sharp increase in firn-ice content in the form of thick widespread layers in the percolation zone, which decreases the capacity of the firn to store meltwater. The estimated total annual ice content retained in the near-surface firn in areas with positive surface mass balance west of the ice divide in Greenland reached a maximum of 74 ± 25 Gt in 2012, compared to the 1958-1999 average of 13 ± 2 Gt, while the percolation zone area more than doubled between 2003 and 2012. Increased melt and column densification resulted in surface lowering averaging -0.80 ± 0.39 m yr-1 between 1800 and 2800 m in the accumulation zone of western Greenland. Since 2007, modeled annual melt and refreezing rates in the percolation zone at elevations below 2100 m surpass the annual snowfall from the previous year, implying that mass gain in the region is retained after melt in the form of refrozen meltwater. If current melt trends over high elevation regions continue, subsequent changes in firn structure will have implications for the hydrology of the ice sheet and related abrupt seasonal densification could become increasingly significant for altimetry-derived ice sheet mass balance estimates. |
format |
Article in Journal/Newspaper |
author |
De La Peña, S. Howat, I.M. Nienow, P.W. Van Den Broeke, M.R. Mosley-Thompson, E. Price, S.F. Mair, D. Noël, Brice Sole, A.J. |
author_facet |
De La Peña, S. Howat, I.M. Nienow, P.W. Van Den Broeke, M.R. Mosley-Thompson, E. Price, S.F. Mair, D. Noël, Brice Sole, A.J. |
author_sort |
De La Peña, S. |
title |
Changes in the firn structure of the western Greenland Ice Sheet caused by recent warming |
title_short |
Changes in the firn structure of the western Greenland Ice Sheet caused by recent warming |
title_full |
Changes in the firn structure of the western Greenland Ice Sheet caused by recent warming |
title_fullStr |
Changes in the firn structure of the western Greenland Ice Sheet caused by recent warming |
title_full_unstemmed |
Changes in the firn structure of the western Greenland Ice Sheet caused by recent warming |
title_sort |
changes in the firn structure of the western greenland ice sheet caused by recent warming |
publisher |
Copernicus GmbH |
publishDate |
2015 |
url |
https://orbi.uliege.be/handle/2268/301890 https://orbi.uliege.be/bitstream/2268/301890/1/Pena_TC_2015.pdf https://doi.org/10.5194/tc-9-1203-2015 |
genre |
Greenland Ice Sheet The Cryosphere |
genre_facet |
Greenland Ice Sheet The Cryosphere |
op_source |
The Cryosphere, 9 (3), 1203 - 1211 (2015-06-11) |
op_relation |
https://tc.copernicus.org/articles/9/1203/2015/tc-9-1203-2015.pdf urn:issn:1994-0416 urn:issn:1994-0424 https://orbi.uliege.be/handle/2268/301890 info:hdl:2268/301890 https://orbi.uliege.be/bitstream/2268/301890/1/Pena_TC_2015.pdf doi:10.5194/tc-9-1203-2015 scopus-id:2-s2.0-84937161463 |
op_rights |
open access http://purl.org/coar/access_right/c_abf2 info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/tc-9-1203-2015 |
container_title |
The Cryosphere |
container_volume |
9 |
container_issue |
3 |
container_start_page |
1203 |
op_container_end_page |
1211 |
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1796943143088685056 |