Impact of West Antarctic Ice Shelf melting on the 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...
Main Authors: | , , |
---|---|
Format: | Text |
Language: | English |
Published: |
2019
|
Subjects: | |
Online Access: | https://doi.org/10.5194/tc-2019-244 https://www.the-cryosphere-discuss.net/tc-2019-244/ |
id |
ftcopernicus:oai:publications.copernicus.org:tcd80885 |
---|---|
record_format |
openpolar |
spelling |
ftcopernicus:oai:publications.copernicus.org:tcd80885 2023-05-15T13:35:08+02:00 Impact of West Antarctic Ice Shelf melting on the Southern Ocean Hydrography Nakayama, Yoshihiro Timmermann, Ralph Hellmer, Hartmut 2019-12-02 application/pdf https://doi.org/10.5194/tc-2019-244 https://www.the-cryosphere-discuss.net/tc-2019-244/ eng eng doi:10.5194/tc-2019-244 https://www.the-cryosphere-discuss.net/tc-2019-244/ eISSN: 1994-0424 Text 2019 ftcopernicus https://doi.org/10.5194/tc-2019-244 2019-12-24T09:48:08Z 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 never been 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 propagates further downstream along the East Antarctic coast into the Weddell Sea. Our experiments also show the timescales for the freshening signal to reach other regions around the Antarctic continent. The freshening signal propagates onto the RS continental shelf within a year of model simulation, while it takes roughly 5–10 years and 10–15 years to propagate into the region off Cape Darnley and into the Weddell Sea, respectively. This advection of freshening signal} possibly modulates the properties of dense shelf water and impacts the production of Antarctic Bottom Water. Text Antarc* Antarctic Ice Shelf Ice Shelves Ross Sea Sea ice Southern Ocean Weddell Sea Copernicus Publications: E-Journals 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 The Antarctic Weddell Weddell Sea |
institution |
Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
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 never been 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 propagates further downstream along the East Antarctic coast into the Weddell Sea. Our experiments also show the timescales for the freshening signal to reach other regions around the Antarctic continent. The freshening signal propagates onto the RS continental shelf within a year of model simulation, while it takes roughly 5–10 years and 10–15 years to propagate into the region off Cape Darnley and into the Weddell Sea, respectively. This advection of freshening signal} possibly modulates the properties of dense shelf water and impacts the production of Antarctic Bottom Water. |
format |
Text |
author |
Nakayama, Yoshihiro Timmermann, Ralph Hellmer, Hartmut |
spellingShingle |
Nakayama, Yoshihiro Timmermann, Ralph Hellmer, Hartmut Impact of West Antarctic Ice Shelf melting on the Southern Ocean Hydrography |
author_facet |
Nakayama, Yoshihiro Timmermann, Ralph Hellmer, Hartmut |
author_sort |
Nakayama, Yoshihiro |
title |
Impact of West Antarctic Ice Shelf melting on the Southern Ocean Hydrography |
title_short |
Impact of West Antarctic Ice Shelf melting on the Southern Ocean Hydrography |
title_full |
Impact of West Antarctic Ice Shelf melting on the Southern Ocean Hydrography |
title_fullStr |
Impact of West Antarctic Ice Shelf melting on the Southern Ocean Hydrography |
title_full_unstemmed |
Impact of West Antarctic Ice Shelf melting on the Southern Ocean Hydrography |
title_sort |
impact of west antarctic ice shelf melting on the southern ocean hydrography |
publishDate |
2019 |
url |
https://doi.org/10.5194/tc-2019-244 https://www.the-cryosphere-discuss.net/tc-2019-244/ |
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 The Antarctic Weddell Weddell Sea |
geographic_facet |
Antarctic Cape Darnley Darnley Ross Sea Southern Ocean The Antarctic 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_source |
eISSN: 1994-0424 |
op_relation |
doi:10.5194/tc-2019-244 https://www.the-cryosphere-discuss.net/tc-2019-244/ |
op_doi |
https://doi.org/10.5194/tc-2019-244 |
_version_ |
1766061323136794624 |