Southern Weddell Sea surface freshwater flux modulated by icescape and atmospheric forcing
Sea ice formation dominates surface salt forcing in the southern Weddell Sea. Brine rejected in the process of sea ice production results in the production of High Salinity Shelf Water (HSSW) that feeds the global overturning circulation and fuels the basal melt of the adjacent ice shelf. The strong...
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Online Access: | https://doi.org/10.5194/os-19-1791-2023 https://os.copernicus.org/articles/19/1791/2023/ |
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ftcopernicus:oai:publications.copernicus.org:os110760 2024-01-14T10:05:56+01:00 Southern Weddell Sea surface freshwater flux modulated by icescape and atmospheric forcing Stulic, Lukrecia Timmermann, Ralph Paul, Stephan Zentek, Rolf Heinemann, Günther Kanzow, Torsten 2023-12-14 application/pdf https://doi.org/10.5194/os-19-1791-2023 https://os.copernicus.org/articles/19/1791/2023/ eng eng doi:10.5194/os-19-1791-2023 https://os.copernicus.org/articles/19/1791/2023/ eISSN: 1812-0792 Text 2023 ftcopernicus https://doi.org/10.5194/os-19-1791-2023 2023-12-18T17:24:16Z Sea ice formation dominates surface salt forcing in the southern Weddell Sea. Brine rejected in the process of sea ice production results in the production of High Salinity Shelf Water (HSSW) that feeds the global overturning circulation and fuels the basal melt of the adjacent ice shelf. The strongest sea ice production rates are found in coastal polynyas, where steady offshore winds promote divergent ice movement during the freezing season. We used the Finite Element Sea ice–ice shelf–Ocean Model (FESOM) forced by output from the regional atmospheric model COSMO-CLM (CCLM) with 14 km horizontal resolution to investigate the role of polynyas for the surface freshwater flux of the southern Weddell Sea (2002–2017). The presence of stationary icescape features (i.e., fast-ice areas and grounded icebergs) can influence the formation of polynyas and, therefore, impact sea ice production. The representation of the icescape in our model is included by prescribing the position, shape and temporal evolution of a largely immobile ice mélange formed between the Filchner–Ronne Ice Shelf (FRIS) and a major grounded iceberg based on satellite data. We find that 70 % of the ice produced on the continental shelf of the southern Weddell Sea is exported from the region. While coastal polynyas cover 2 % of the continental shelf area, sea ice production within the coastal polynyas accounts for 17 % of the overall annual sea ice production (1509 km 3 ). The largest contributions come from the Ronne Ice Shelf and Brunt Ice Shelf polynyas and polynyas associated with the ice mélange. Furthermore, we investigate the sensitivity of the polynya-based ice production to the (i) representation of the icescape and (ii) regional atmospheric forcing. Although large-scale atmospheric fields determine the sea ice production outside polynyas, both the treatment of the icescape and the regional atmospheric forcing are important for the regional patterns of sea ice production in polynyas. The representation of the ice mélange is crucial for the ... Text Brunt Ice Shelf Filchner Ronne Ice Shelf Filchner-Ronne Ice Shelf Ice Shelf Ronne Ice Shelf Sea ice Weddell Sea Copernicus Publications: E-Journals Weddell Sea Weddell Ronne Ice Shelf ENVELOPE(-61.000,-61.000,-78.500,-78.500) Brunt Ice Shelf ENVELOPE(-22.500,-22.500,-74.750,-74.750) Ocean Science 19 6 1791 1808 |
institution |
Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
Sea ice formation dominates surface salt forcing in the southern Weddell Sea. Brine rejected in the process of sea ice production results in the production of High Salinity Shelf Water (HSSW) that feeds the global overturning circulation and fuels the basal melt of the adjacent ice shelf. The strongest sea ice production rates are found in coastal polynyas, where steady offshore winds promote divergent ice movement during the freezing season. We used the Finite Element Sea ice–ice shelf–Ocean Model (FESOM) forced by output from the regional atmospheric model COSMO-CLM (CCLM) with 14 km horizontal resolution to investigate the role of polynyas for the surface freshwater flux of the southern Weddell Sea (2002–2017). The presence of stationary icescape features (i.e., fast-ice areas and grounded icebergs) can influence the formation of polynyas and, therefore, impact sea ice production. The representation of the icescape in our model is included by prescribing the position, shape and temporal evolution of a largely immobile ice mélange formed between the Filchner–Ronne Ice Shelf (FRIS) and a major grounded iceberg based on satellite data. We find that 70 % of the ice produced on the continental shelf of the southern Weddell Sea is exported from the region. While coastal polynyas cover 2 % of the continental shelf area, sea ice production within the coastal polynyas accounts for 17 % of the overall annual sea ice production (1509 km 3 ). The largest contributions come from the Ronne Ice Shelf and Brunt Ice Shelf polynyas and polynyas associated with the ice mélange. Furthermore, we investigate the sensitivity of the polynya-based ice production to the (i) representation of the icescape and (ii) regional atmospheric forcing. Although large-scale atmospheric fields determine the sea ice production outside polynyas, both the treatment of the icescape and the regional atmospheric forcing are important for the regional patterns of sea ice production in polynyas. The representation of the ice mélange is crucial for the ... |
format |
Text |
author |
Stulic, Lukrecia Timmermann, Ralph Paul, Stephan Zentek, Rolf Heinemann, Günther Kanzow, Torsten |
spellingShingle |
Stulic, Lukrecia Timmermann, Ralph Paul, Stephan Zentek, Rolf Heinemann, Günther Kanzow, Torsten Southern Weddell Sea surface freshwater flux modulated by icescape and atmospheric forcing |
author_facet |
Stulic, Lukrecia Timmermann, Ralph Paul, Stephan Zentek, Rolf Heinemann, Günther Kanzow, Torsten |
author_sort |
Stulic, Lukrecia |
title |
Southern Weddell Sea surface freshwater flux modulated by icescape and atmospheric forcing |
title_short |
Southern Weddell Sea surface freshwater flux modulated by icescape and atmospheric forcing |
title_full |
Southern Weddell Sea surface freshwater flux modulated by icescape and atmospheric forcing |
title_fullStr |
Southern Weddell Sea surface freshwater flux modulated by icescape and atmospheric forcing |
title_full_unstemmed |
Southern Weddell Sea surface freshwater flux modulated by icescape and atmospheric forcing |
title_sort |
southern weddell sea surface freshwater flux modulated by icescape and atmospheric forcing |
publishDate |
2023 |
url |
https://doi.org/10.5194/os-19-1791-2023 https://os.copernicus.org/articles/19/1791/2023/ |
long_lat |
ENVELOPE(-61.000,-61.000,-78.500,-78.500) ENVELOPE(-22.500,-22.500,-74.750,-74.750) |
geographic |
Weddell Sea Weddell Ronne Ice Shelf Brunt Ice Shelf |
geographic_facet |
Weddell Sea Weddell Ronne Ice Shelf Brunt Ice Shelf |
genre |
Brunt Ice Shelf Filchner Ronne Ice Shelf Filchner-Ronne Ice Shelf Ice Shelf Ronne Ice Shelf Sea ice Weddell Sea |
genre_facet |
Brunt Ice Shelf Filchner Ronne Ice Shelf Filchner-Ronne Ice Shelf Ice Shelf Ronne Ice Shelf Sea ice Weddell Sea |
op_source |
eISSN: 1812-0792 |
op_relation |
doi:10.5194/os-19-1791-2023 https://os.copernicus.org/articles/19/1791/2023/ |
op_doi |
https://doi.org/10.5194/os-19-1791-2023 |
container_title |
Ocean Science |
container_volume |
19 |
container_issue |
6 |
container_start_page |
1791 |
op_container_end_page |
1808 |
_version_ |
1788060237656227840 |