Impact of millennial-scale oceanic variability on the Greenland ice-sheet evolution throughout the last glacial period
Temperature reconstructions from Greenland ice-sheet (GrIS) ice cores indicate the occurrence of more than 20 abrupt warmings during the last glacial period (LGP) known as Dansgaard-Oeschger (D-O) events. Although their ultimate cause is still debated, evidence from both proxy data and modelling stu...
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fttriple:oai:gotriple.eu:slxc_U1fyRagJvQ5VE3f_ 2023-05-15T16:28:39+02:00 Impact of millennial-scale oceanic variability on the Greenland ice-sheet evolution throughout the last glacial period Tabone, Ilaria Robinson, Alexander Alvarez-Solas, Jorge Montoya, Marisa 2019-03-28 https://doi.org/10.5194/cp-15-593-2019 https://cp.copernicus.org/articles/15/593/2019/ en eng Copernicus Publications doi:10.5194/cp-15-593-2019 10670/1.pg0a6p 1814-9324 1814-9332 https://cp.copernicus.org/articles/15/593/2019/ undefined Geographica Helvetica - geography eISSN: 1814-9332 envir geo Text https://vocabularies.coar-repositories.org/resource_types/c_18cf/ Journal Article https://vocabularies.coar-repositories.org/resource_types/c_6501/ 2019 fttriple https://doi.org/10.5194/cp-15-593-2019 2023-01-22T17:52:19Z Temperature reconstructions from Greenland ice-sheet (GrIS) ice cores indicate the occurrence of more than 20 abrupt warmings during the last glacial period (LGP) known as Dansgaard-Oeschger (D-O) events. Although their ultimate cause is still debated, evidence from both proxy data and modelling studies robustly links these to reorganisations of the Atlantic Meridional Overturning Circulation (AMOC). During the LGP, the GrIS expanded as far as the continental shelf break and was thus more directly exposed to oceanic changes than in the present. Therefore oceanic temperature fluctuations on millennial timescales could have had a non-negligible impact on the GrIS. Here we assess the effect of millennial-scale oceanic variability on the GrIS evolution from the last interglacial to the present day. To do so, we use a three-dimensional hybrid ice-sheet–shelf model forced by subsurface oceanic temperature fluctuations, assumed to increase during D-O stadials and decrease during D-O interstadials. Since in our model the atmospheric forcing follows orbital variations only, the increase in total melting at millennial timescales is a direct result of an increase in basal melting. We show that the GrIS evolution during the LGP could have been strongly influenced by oceanic changes on millennial timescales, leading to oceanically induced ice-volume contributions above 1 m sea level equivalent (SLE). Also, our results suggest that the increased flux of GrIS icebergs as inferred from North Atlantic proxy records could have been triggered, or intensified, by peaks in melting at the base of the ice shelves resulting from increasing subsurface oceanic temperatures during D-O stadials. Several regions across the GrIS could thus have been responsible for ice mass discharge during D-O events, opening the possibility of a non-negligible role of the GrIS in oceanic reorganisations throughout the LGP. Article in Journal/Newspaper Greenland Ice Sheet Ice Shelves North Atlantic Unknown Greenland Climate of the Past 15 2 593 609 |
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envir geo Tabone, Ilaria Robinson, Alexander Alvarez-Solas, Jorge Montoya, Marisa Impact of millennial-scale oceanic variability on the Greenland ice-sheet evolution throughout the last glacial period |
topic_facet |
envir geo |
description |
Temperature reconstructions from Greenland ice-sheet (GrIS) ice cores indicate the occurrence of more than 20 abrupt warmings during the last glacial period (LGP) known as Dansgaard-Oeschger (D-O) events. Although their ultimate cause is still debated, evidence from both proxy data and modelling studies robustly links these to reorganisations of the Atlantic Meridional Overturning Circulation (AMOC). During the LGP, the GrIS expanded as far as the continental shelf break and was thus more directly exposed to oceanic changes than in the present. Therefore oceanic temperature fluctuations on millennial timescales could have had a non-negligible impact on the GrIS. Here we assess the effect of millennial-scale oceanic variability on the GrIS evolution from the last interglacial to the present day. To do so, we use a three-dimensional hybrid ice-sheet–shelf model forced by subsurface oceanic temperature fluctuations, assumed to increase during D-O stadials and decrease during D-O interstadials. Since in our model the atmospheric forcing follows orbital variations only, the increase in total melting at millennial timescales is a direct result of an increase in basal melting. We show that the GrIS evolution during the LGP could have been strongly influenced by oceanic changes on millennial timescales, leading to oceanically induced ice-volume contributions above 1 m sea level equivalent (SLE). Also, our results suggest that the increased flux of GrIS icebergs as inferred from North Atlantic proxy records could have been triggered, or intensified, by peaks in melting at the base of the ice shelves resulting from increasing subsurface oceanic temperatures during D-O stadials. Several regions across the GrIS could thus have been responsible for ice mass discharge during D-O events, opening the possibility of a non-negligible role of the GrIS in oceanic reorganisations throughout the LGP. |
format |
Article in Journal/Newspaper |
author |
Tabone, Ilaria Robinson, Alexander Alvarez-Solas, Jorge Montoya, Marisa |
author_facet |
Tabone, Ilaria Robinson, Alexander Alvarez-Solas, Jorge Montoya, Marisa |
author_sort |
Tabone, Ilaria |
title |
Impact of millennial-scale oceanic variability on the Greenland ice-sheet evolution throughout the last glacial period |
title_short |
Impact of millennial-scale oceanic variability on the Greenland ice-sheet evolution throughout the last glacial period |
title_full |
Impact of millennial-scale oceanic variability on the Greenland ice-sheet evolution throughout the last glacial period |
title_fullStr |
Impact of millennial-scale oceanic variability on the Greenland ice-sheet evolution throughout the last glacial period |
title_full_unstemmed |
Impact of millennial-scale oceanic variability on the Greenland ice-sheet evolution throughout the last glacial period |
title_sort |
impact of millennial-scale oceanic variability on the greenland ice-sheet evolution throughout the last glacial period |
publisher |
Copernicus Publications |
publishDate |
2019 |
url |
https://doi.org/10.5194/cp-15-593-2019 https://cp.copernicus.org/articles/15/593/2019/ |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Ice Sheet Ice Shelves North Atlantic |
genre_facet |
Greenland Ice Sheet Ice Shelves North Atlantic |
op_source |
Geographica Helvetica - geography eISSN: 1814-9332 |
op_relation |
doi:10.5194/cp-15-593-2019 10670/1.pg0a6p 1814-9324 1814-9332 https://cp.copernicus.org/articles/15/593/2019/ |
op_rights |
undefined |
op_doi |
https://doi.org/10.5194/cp-15-593-2019 |
container_title |
Climate of the Past |
container_volume |
15 |
container_issue |
2 |
container_start_page |
593 |
op_container_end_page |
609 |
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1766018324166082560 |