Impact of West Antarctic ice shelf melting on Southern Ocean hydrography
Previous studies show accelerations of West Antarctic glaciers, implying that basal melt rates of these glaciers were previously small and increased in the middle of the 20th century. This enhanced melting is a likely source of the observed Ross Sea (RS) freshening, but its long-term impact on the S...
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Online Access: | http://hdl.handle.net/2115/79210 https://doi.org/10.5194/tc-14-2205-2020 |
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fthokunivhus:oai:eprints.lib.hokudai.ac.jp:2115/79210 2023-05-15T13:51:33+02:00 Impact of West Antarctic ice shelf melting on Southern Ocean hydrography Nakayama, Yoshihiro Timmermann, Ralph Hellmer, Hartmut H. http://hdl.handle.net/2115/79210 https://doi.org/10.5194/tc-14-2205-2020 eng eng Copernicus Publications http://hdl.handle.net/2115/79210 Cryosphere, 14(7): 2205-2216 http://dx.doi.org/10.5194/tc-14-2205-2020 https://creativecommons.org/licenses/by/4.0/ CC-BY article fthokunivhus https://doi.org/10.5194/tc-14-2205-2020 2022-11-18T01:06:07Z Previous studies show accelerations of West Antarctic glaciers, implying that basal melt rates of these glaciers were previously small and increased in the middle of the 20th century. This enhanced melting is a likely source of the observed Ross Sea (RS) freshening, but its long-term impact on the Southern Ocean hydrography has not been well investigated. Here, we conduct coupled sea ice-ice shelf-ocean simulations with different levels of ice shelf melting from West Antarctic glaciers. Freshening of RS shelf and bottom water is simulated with enhanced West Antarctic ice shelf melting, while no significant changes in shelf water properties are simulated when West Antarctic ice shelf melting is small. We further show that the freshening caused by glacial meltwater from ice shelves in the Amundsen and Bellingshausen seas can propagate further downstream along the East Antarctic coast into the Weddell Sea. The freshening signal propagates onto the RS continental shelf within a year of model simulation, while it takes roughly 5-10 and 10-15 years to propagate into the region off Cape Darnley and into the Weddell Sea, respectively. This advection of freshening modulates the shelf water properties and possibly impacts the production of Antarctic Bottom Water if the enhanced melting of West Antarctic ice shelves continues for a longer period. Article in Journal/Newspaper Antarc* Antarctic Ice Shelf Ice Shelves Ross Sea Sea ice Southern Ocean Weddell Sea Hokkaido University Collection of Scholarly and Academic Papers (HUSCAP) Antarctic Cape Darnley ENVELOPE(69.567,69.567,-67.738,-67.738) Darnley ENVELOPE(69.717,69.717,-67.717,-67.717) Ross Sea Southern Ocean Weddell Weddell Sea The Cryosphere 14 7 2205 2216 |
institution |
Open Polar |
collection |
Hokkaido University Collection of Scholarly and Academic Papers (HUSCAP) |
op_collection_id |
fthokunivhus |
language |
English |
description |
Previous studies show accelerations of West Antarctic glaciers, implying that basal melt rates of these glaciers were previously small and increased in the middle of the 20th century. This enhanced melting is a likely source of the observed Ross Sea (RS) freshening, but its long-term impact on the Southern Ocean hydrography has not been well investigated. Here, we conduct coupled sea ice-ice shelf-ocean simulations with different levels of ice shelf melting from West Antarctic glaciers. Freshening of RS shelf and bottom water is simulated with enhanced West Antarctic ice shelf melting, while no significant changes in shelf water properties are simulated when West Antarctic ice shelf melting is small. We further show that the freshening caused by glacial meltwater from ice shelves in the Amundsen and Bellingshausen seas can propagate further downstream along the East Antarctic coast into the Weddell Sea. The freshening signal propagates onto the RS continental shelf within a year of model simulation, while it takes roughly 5-10 and 10-15 years to propagate into the region off Cape Darnley and into the Weddell Sea, respectively. This advection of freshening modulates the shelf water properties and possibly impacts the production of Antarctic Bottom Water if the enhanced melting of West Antarctic ice shelves continues for a longer period. |
format |
Article in Journal/Newspaper |
author |
Nakayama, Yoshihiro Timmermann, Ralph Hellmer, Hartmut H. |
spellingShingle |
Nakayama, Yoshihiro Timmermann, Ralph Hellmer, Hartmut H. Impact of West Antarctic ice shelf melting on Southern Ocean hydrography |
author_facet |
Nakayama, Yoshihiro Timmermann, Ralph Hellmer, Hartmut H. |
author_sort |
Nakayama, Yoshihiro |
title |
Impact of West Antarctic ice shelf melting on Southern Ocean hydrography |
title_short |
Impact of West Antarctic ice shelf melting on Southern Ocean hydrography |
title_full |
Impact of West Antarctic ice shelf melting on Southern Ocean hydrography |
title_fullStr |
Impact of West Antarctic ice shelf melting on Southern Ocean hydrography |
title_full_unstemmed |
Impact of West Antarctic ice shelf melting on Southern Ocean hydrography |
title_sort |
impact of west antarctic ice shelf melting on southern ocean hydrography |
publisher |
Copernicus Publications |
url |
http://hdl.handle.net/2115/79210 https://doi.org/10.5194/tc-14-2205-2020 |
long_lat |
ENVELOPE(69.567,69.567,-67.738,-67.738) ENVELOPE(69.717,69.717,-67.717,-67.717) |
geographic |
Antarctic Cape Darnley Darnley Ross Sea Southern Ocean Weddell Weddell Sea |
geographic_facet |
Antarctic Cape Darnley Darnley Ross Sea Southern Ocean Weddell Weddell Sea |
genre |
Antarc* Antarctic Ice Shelf Ice Shelves Ross Sea Sea ice Southern Ocean Weddell Sea |
genre_facet |
Antarc* Antarctic Ice Shelf Ice Shelves Ross Sea Sea ice Southern Ocean Weddell Sea |
op_relation |
http://hdl.handle.net/2115/79210 Cryosphere, 14(7): 2205-2216 http://dx.doi.org/10.5194/tc-14-2205-2020 |
op_rights |
https://creativecommons.org/licenses/by/4.0/ |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.5194/tc-14-2205-2020 |
container_title |
The Cryosphere |
container_volume |
14 |
container_issue |
7 |
container_start_page |
2205 |
op_container_end_page |
2216 |
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1766255455617679360 |