Increased Greenland melt triggered by large-scale, year-round cyclonic moisture intrusions
Surface melting is a major driver of Greenland's mass loss. Yet, the mechanisms that trigger melt are still insufficiently understood because seasonally based studies blend processes initiating melt with positive feedbacks. Here, we focus on the triggers of melt by examining the synoptic atmosp...
Published in: | The Cryosphere |
---|---|
Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Copernicus Publications (EGU)
2019
|
Subjects: | |
Online Access: | https://oceanrep.geomar.de/id/eprint/44927/ https://oceanrep.geomar.de/id/eprint/44927/1/tc-13-815-2019.pdf https://oceanrep.geomar.de/id/eprint/44927/2/tc-13-815-2019-supplement.pdf https://doi.org/10.5194/tc-13-815-2019 |
id |
ftoceanrep:oai:oceanrep.geomar.de:44927 |
---|---|
record_format |
openpolar |
spelling |
ftoceanrep:oai:oceanrep.geomar.de:44927 2023-05-15T16:27:51+02:00 Increased Greenland melt triggered by large-scale, year-round cyclonic moisture intrusions Oltmanns, Marilena Straneo, Fiammetta Tedesco, Marco 2019-03-07 text https://oceanrep.geomar.de/id/eprint/44927/ https://oceanrep.geomar.de/id/eprint/44927/1/tc-13-815-2019.pdf https://oceanrep.geomar.de/id/eprint/44927/2/tc-13-815-2019-supplement.pdf https://doi.org/10.5194/tc-13-815-2019 en eng Copernicus Publications (EGU) https://oceanrep.geomar.de/id/eprint/44927/1/tc-13-815-2019.pdf https://oceanrep.geomar.de/id/eprint/44927/2/tc-13-815-2019-supplement.pdf Oltmanns, M. , Straneo, F. and Tedesco, M. (2019) Increased Greenland melt triggered by large-scale, year-round cyclonic moisture intrusions. Open Access The Cryosphere, 13 . pp. 815-825. DOI 10.5194/tc-13-815-2019 <https://doi.org/10.5194/tc-13-815-2019>. doi:10.5194/tc-13-815-2019 cc_by_4.0 info:eu-repo/semantics/openAccess Article PeerReviewed info:eu-repo/semantics/article 2019 ftoceanrep https://doi.org/10.5194/tc-13-815-2019 2023-04-07T15:42:30Z Surface melting is a major driver of Greenland's mass loss. Yet, the mechanisms that trigger melt are still insufficiently understood because seasonally based studies blend processes initiating melt with positive feedbacks. Here, we focus on the triggers of melt by examining the synoptic atmospheric conditions associated with 313 rapid melt increases, detected in a satellite-derived melt extent product, equally distributed throughout the year over the period 1979–2012. By combining reanalysis and weather station data, we show that melt is initiated by a cyclone-driven, southerly flow of warm, moist air, which gives rise to large-scale precipitation. A decomposition of the synoptic atmospheric variability over Greenland suggests that the identified, melt-triggering weather pattern accounts for ∼40 % of the net precipitation, but increases in the frequency, duration and areal extent of the initiated melting have shifted the line between mass gain and mass loss as more melt and rainwater run off or accumulate in the snowpack. Using a regional climate model, we estimate that the initiated melting more than doubled over the investigated period, amounting to ∼28 % of the overall surface melt and revealing that, despite the involved mass gain, year-round precipitation events are participating in the ice sheet's decline. Article in Journal/Newspaper Greenland The Cryosphere OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Greenland The Cryosphere 13 3 815 825 |
institution |
Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
English |
description |
Surface melting is a major driver of Greenland's mass loss. Yet, the mechanisms that trigger melt are still insufficiently understood because seasonally based studies blend processes initiating melt with positive feedbacks. Here, we focus on the triggers of melt by examining the synoptic atmospheric conditions associated with 313 rapid melt increases, detected in a satellite-derived melt extent product, equally distributed throughout the year over the period 1979–2012. By combining reanalysis and weather station data, we show that melt is initiated by a cyclone-driven, southerly flow of warm, moist air, which gives rise to large-scale precipitation. A decomposition of the synoptic atmospheric variability over Greenland suggests that the identified, melt-triggering weather pattern accounts for ∼40 % of the net precipitation, but increases in the frequency, duration and areal extent of the initiated melting have shifted the line between mass gain and mass loss as more melt and rainwater run off or accumulate in the snowpack. Using a regional climate model, we estimate that the initiated melting more than doubled over the investigated period, amounting to ∼28 % of the overall surface melt and revealing that, despite the involved mass gain, year-round precipitation events are participating in the ice sheet's decline. |
format |
Article in Journal/Newspaper |
author |
Oltmanns, Marilena Straneo, Fiammetta Tedesco, Marco |
spellingShingle |
Oltmanns, Marilena Straneo, Fiammetta Tedesco, Marco Increased Greenland melt triggered by large-scale, year-round cyclonic moisture intrusions |
author_facet |
Oltmanns, Marilena Straneo, Fiammetta Tedesco, Marco |
author_sort |
Oltmanns, Marilena |
title |
Increased Greenland melt triggered by large-scale, year-round cyclonic moisture intrusions |
title_short |
Increased Greenland melt triggered by large-scale, year-round cyclonic moisture intrusions |
title_full |
Increased Greenland melt triggered by large-scale, year-round cyclonic moisture intrusions |
title_fullStr |
Increased Greenland melt triggered by large-scale, year-round cyclonic moisture intrusions |
title_full_unstemmed |
Increased Greenland melt triggered by large-scale, year-round cyclonic moisture intrusions |
title_sort |
increased greenland melt triggered by large-scale, year-round cyclonic moisture intrusions |
publisher |
Copernicus Publications (EGU) |
publishDate |
2019 |
url |
https://oceanrep.geomar.de/id/eprint/44927/ https://oceanrep.geomar.de/id/eprint/44927/1/tc-13-815-2019.pdf https://oceanrep.geomar.de/id/eprint/44927/2/tc-13-815-2019-supplement.pdf https://doi.org/10.5194/tc-13-815-2019 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland The Cryosphere |
genre_facet |
Greenland The Cryosphere |
op_relation |
https://oceanrep.geomar.de/id/eprint/44927/1/tc-13-815-2019.pdf https://oceanrep.geomar.de/id/eprint/44927/2/tc-13-815-2019-supplement.pdf Oltmanns, M. , Straneo, F. and Tedesco, M. (2019) Increased Greenland melt triggered by large-scale, year-round cyclonic moisture intrusions. Open Access The Cryosphere, 13 . pp. 815-825. DOI 10.5194/tc-13-815-2019 <https://doi.org/10.5194/tc-13-815-2019>. doi:10.5194/tc-13-815-2019 |
op_rights |
cc_by_4.0 info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/tc-13-815-2019 |
container_title |
The Cryosphere |
container_volume |
13 |
container_issue |
3 |
container_start_page |
815 |
op_container_end_page |
825 |
_version_ |
1766017411684761600 |