The staggered retreat of grounded ice in Ross Sea, Antarctica since the LGM
The retreat of the West Antarctic Ice Sheet (WAIS) in the Ross Sea after the Last Glacial Maximum (LGM) was more significant than for any other Antarctic sector. Here we combined the available chronology of retreat with new mapping of seismically resolvable grounding zone wedges (GZWs). Mapping GZWs...
Main Authors: | , |
---|---|
Format: | Text |
Language: | English |
Published: |
2024
|
Subjects: | |
Online Access: | https://doi.org/10.5194/egusphere-2023-1397 https://egusphere.copernicus.org/preprints/2023/egusphere-2023-1397/ |
id |
ftcopernicus:oai:publications.copernicus.org:egusphere112759 |
---|---|
record_format |
openpolar |
spelling |
ftcopernicus:oai:publications.copernicus.org:egusphere112759 2024-06-23T07:46:38+00:00 The staggered retreat of grounded ice in Ross Sea, Antarctica since the LGM Danielson, Matthew A. Bart, Philip J. 2024-03-08 application/pdf https://doi.org/10.5194/egusphere-2023-1397 https://egusphere.copernicus.org/preprints/2023/egusphere-2023-1397/ eng eng doi:10.5194/egusphere-2023-1397 https://egusphere.copernicus.org/preprints/2023/egusphere-2023-1397/ eISSN: Text 2024 ftcopernicus https://doi.org/10.5194/egusphere-2023-1397 2024-06-13T01:23:50Z The retreat of the West Antarctic Ice Sheet (WAIS) in the Ross Sea after the Last Glacial Maximum (LGM) was more significant than for any other Antarctic sector. Here we combined the available chronology of retreat with new mapping of seismically resolvable grounding zone wedges (GZWs). Mapping GZWs is important because they record the locations of former stillstands in the extent of grounded ice for individual ice streams during the overall retreat. Our analysis shows that the longest stillstands occurred early in the deglacial period and had millennial durations. Stillstands ended abruptly with retreat distances measured in the tens to hundreds of kilometers creating deep embayments in the extent of grounded ice across the Ross Sea. The location of embayments shifted through time. The available chronological data show that cessation of WAIS and East Antarctic Ice Sheet (EAIS) stillstands was highly asynchronous across at least 5000 years. There was a general shift to shorter stillstands throughout the deglacial period. The asynchronous collapse of individual catchments during the deglacial period suggests that the Ross Sea sector would have contributed to multiple episodes of relatively small-amplitude sea-level rise as the WAIS and EAIS retreated from the region. The high sinuosity of the modern grounding zone in the Ross Sea suggests that this style of retreat persists. Text Antarc* Antarctic Antarctica Ice Sheet Ross Sea Copernicus Publications: E-Journals Antarctic East Antarctic Ice Sheet Ross Sea West Antarctic Ice Sheet |
institution |
Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
The retreat of the West Antarctic Ice Sheet (WAIS) in the Ross Sea after the Last Glacial Maximum (LGM) was more significant than for any other Antarctic sector. Here we combined the available chronology of retreat with new mapping of seismically resolvable grounding zone wedges (GZWs). Mapping GZWs is important because they record the locations of former stillstands in the extent of grounded ice for individual ice streams during the overall retreat. Our analysis shows that the longest stillstands occurred early in the deglacial period and had millennial durations. Stillstands ended abruptly with retreat distances measured in the tens to hundreds of kilometers creating deep embayments in the extent of grounded ice across the Ross Sea. The location of embayments shifted through time. The available chronological data show that cessation of WAIS and East Antarctic Ice Sheet (EAIS) stillstands was highly asynchronous across at least 5000 years. There was a general shift to shorter stillstands throughout the deglacial period. The asynchronous collapse of individual catchments during the deglacial period suggests that the Ross Sea sector would have contributed to multiple episodes of relatively small-amplitude sea-level rise as the WAIS and EAIS retreated from the region. The high sinuosity of the modern grounding zone in the Ross Sea suggests that this style of retreat persists. |
format |
Text |
author |
Danielson, Matthew A. Bart, Philip J. |
spellingShingle |
Danielson, Matthew A. Bart, Philip J. The staggered retreat of grounded ice in Ross Sea, Antarctica since the LGM |
author_facet |
Danielson, Matthew A. Bart, Philip J. |
author_sort |
Danielson, Matthew A. |
title |
The staggered retreat of grounded ice in Ross Sea, Antarctica since the LGM |
title_short |
The staggered retreat of grounded ice in Ross Sea, Antarctica since the LGM |
title_full |
The staggered retreat of grounded ice in Ross Sea, Antarctica since the LGM |
title_fullStr |
The staggered retreat of grounded ice in Ross Sea, Antarctica since the LGM |
title_full_unstemmed |
The staggered retreat of grounded ice in Ross Sea, Antarctica since the LGM |
title_sort |
staggered retreat of grounded ice in ross sea, antarctica since the lgm |
publishDate |
2024 |
url |
https://doi.org/10.5194/egusphere-2023-1397 https://egusphere.copernicus.org/preprints/2023/egusphere-2023-1397/ |
geographic |
Antarctic East Antarctic Ice Sheet Ross Sea West Antarctic Ice Sheet |
geographic_facet |
Antarctic East Antarctic Ice Sheet Ross Sea West Antarctic Ice Sheet |
genre |
Antarc* Antarctic Antarctica Ice Sheet Ross Sea |
genre_facet |
Antarc* Antarctic Antarctica Ice Sheet Ross Sea |
op_source |
eISSN: |
op_relation |
doi:10.5194/egusphere-2023-1397 https://egusphere.copernicus.org/preprints/2023/egusphere-2023-1397/ |
op_doi |
https://doi.org/10.5194/egusphere-2023-1397 |
_version_ |
1802647143866957824 |