Southern Ocean warming and increased ice shelf basal melting in the 21st and 22nd centuries based on coupled ice-ocean finite-element modelling
In the framework of the EU project Ice2sea we utilize a global finite element sea ice - ice shelf - ocean model (FESOM), focused on the Antarctic marginal seas, to assess projections of ice shelf basal melting in a warmer climate. Ice shelf - ocean interaction is described using a three-equation sys...
Main Authors: | , |
---|---|
Format: | Conference Object |
Language: | unknown |
Published: |
Geophysical Research Abstracts
2013
|
Subjects: | |
Online Access: | https://epic.awi.de/id/eprint/34183/ http://meetingorganizer.copernicus.org/EGU2013/EGU2013-10861.pdf https://hdl.handle.net/10013/epic.42481 |
id |
ftawi:oai:epic.awi.de:34183 |
---|---|
record_format |
openpolar |
spelling |
ftawi:oai:epic.awi.de:34183 2023-05-15T13:40:26+02:00 Southern Ocean warming and increased ice shelf basal melting in the 21st and 22nd centuries based on coupled ice-ocean finite-element modelling Timmermann, Ralph Hellmer, Hartmut 2013-04-11 https://epic.awi.de/id/eprint/34183/ http://meetingorganizer.copernicus.org/EGU2013/EGU2013-10861.pdf https://hdl.handle.net/10013/epic.42481 unknown Geophysical Research Abstracts Timmermann, R. and Hellmer, H. orcid:0000-0002-9357-9853 (2013) Southern Ocean warming and increased ice shelf basal melting in the 21st and 22nd centuries based on coupled ice-ocean finite-element modelling , European Geosciences Union General Assembly 2013, Vienna, 7 April 2013 - 12 April 2013 . hdl:10013/epic.42481 EPIC3European Geosciences Union General Assembly 2013, Vienna, 2013-04-07-2013-04-12Geophysical Research Abstracts Conference notRev 2013 ftawi 2021-12-24T15:39:04Z In the framework of the EU project Ice2sea we utilize a global finite element sea ice - ice shelf - ocean model (FESOM), focused on the Antarctic marginal seas, to assess projections of ice shelf basal melting in a warmer climate. Ice shelf - ocean interaction is described using a three-equation system with a diagnostic computation of temperature and salinity at the ice-ocean interface. A tetrahedral mesh with a minimum horizontal resolution of 4 minutes and hybrid vertical coordinates is used. Ice shelf draft, cavity geometry, and global ocean bathymetry have been derived from the RTopo-1 data set. The model is forced with the atmospheric output from two climate models: (1) the Hadley Centre Climate Model (HadCM3) and (2) Max Planck Institute’s ECHAM5/MPI-OM coupled climate model. Data from their 20th-century simulations are used to evaluate the modeled present-day ocean state. Sea-ice coverage is largely realistic in both simulations. Modeled ice shelf basal melt rates compare well with observations in both cases, but are consistently smaller for ECHAM5/MPI-OM. Projections for future ice shelf basal melting are computed using atmospheric output for IPCC scenarios E1 and A1B. Trends in sea ice coverage depend on the scenario chosen but are largely consistent between the two forcing models. In contrast to this, variations of ocean heat content and ice shelf basal melting are only moderate in simulations forced with ECHAM5/MPI-OM data, while a substantial shift towards a warmer regime is found in experiments forced with HadCM3 output. A strong sensitivity to salinity distribution at the continental shelf break is found for the Weddell Sea, where in the HadCM3-A1B experiment warm water starts to pulse onto the southern continental shelf during the 21st century. As these pulses reach deep into the Filchner-Ronne Ice Shelf (FRIS) cavity, basal melting increases by a factor of three to six compared to the present value of about 100 Gt/yr. By the middle of the 22nd century, FRIS becomes the largest contributor to total ice shelf basal mass loss in this simulation. Conference Object Antarc* Antarctic Filchner Ronne Ice Shelf Filchner-Ronne Ice Shelf Ice Shelf Ronne Ice Shelf Sea ice Southern Ocean Weddell Sea Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Antarctic Southern Ocean The Antarctic Weddell Sea Weddell Ronne Ice Shelf ENVELOPE(-61.000,-61.000,-78.500,-78.500) |
institution |
Open Polar |
collection |
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
op_collection_id |
ftawi |
language |
unknown |
description |
In the framework of the EU project Ice2sea we utilize a global finite element sea ice - ice shelf - ocean model (FESOM), focused on the Antarctic marginal seas, to assess projections of ice shelf basal melting in a warmer climate. Ice shelf - ocean interaction is described using a three-equation system with a diagnostic computation of temperature and salinity at the ice-ocean interface. A tetrahedral mesh with a minimum horizontal resolution of 4 minutes and hybrid vertical coordinates is used. Ice shelf draft, cavity geometry, and global ocean bathymetry have been derived from the RTopo-1 data set. The model is forced with the atmospheric output from two climate models: (1) the Hadley Centre Climate Model (HadCM3) and (2) Max Planck Institute’s ECHAM5/MPI-OM coupled climate model. Data from their 20th-century simulations are used to evaluate the modeled present-day ocean state. Sea-ice coverage is largely realistic in both simulations. Modeled ice shelf basal melt rates compare well with observations in both cases, but are consistently smaller for ECHAM5/MPI-OM. Projections for future ice shelf basal melting are computed using atmospheric output for IPCC scenarios E1 and A1B. Trends in sea ice coverage depend on the scenario chosen but are largely consistent between the two forcing models. In contrast to this, variations of ocean heat content and ice shelf basal melting are only moderate in simulations forced with ECHAM5/MPI-OM data, while a substantial shift towards a warmer regime is found in experiments forced with HadCM3 output. A strong sensitivity to salinity distribution at the continental shelf break is found for the Weddell Sea, where in the HadCM3-A1B experiment warm water starts to pulse onto the southern continental shelf during the 21st century. As these pulses reach deep into the Filchner-Ronne Ice Shelf (FRIS) cavity, basal melting increases by a factor of three to six compared to the present value of about 100 Gt/yr. By the middle of the 22nd century, FRIS becomes the largest contributor to total ice shelf basal mass loss in this simulation. |
format |
Conference Object |
author |
Timmermann, Ralph Hellmer, Hartmut |
spellingShingle |
Timmermann, Ralph Hellmer, Hartmut Southern Ocean warming and increased ice shelf basal melting in the 21st and 22nd centuries based on coupled ice-ocean finite-element modelling |
author_facet |
Timmermann, Ralph Hellmer, Hartmut |
author_sort |
Timmermann, Ralph |
title |
Southern Ocean warming and increased ice shelf basal melting in the 21st and 22nd centuries based on coupled ice-ocean finite-element modelling |
title_short |
Southern Ocean warming and increased ice shelf basal melting in the 21st and 22nd centuries based on coupled ice-ocean finite-element modelling |
title_full |
Southern Ocean warming and increased ice shelf basal melting in the 21st and 22nd centuries based on coupled ice-ocean finite-element modelling |
title_fullStr |
Southern Ocean warming and increased ice shelf basal melting in the 21st and 22nd centuries based on coupled ice-ocean finite-element modelling |
title_full_unstemmed |
Southern Ocean warming and increased ice shelf basal melting in the 21st and 22nd centuries based on coupled ice-ocean finite-element modelling |
title_sort |
southern ocean warming and increased ice shelf basal melting in the 21st and 22nd centuries based on coupled ice-ocean finite-element modelling |
publisher |
Geophysical Research Abstracts |
publishDate |
2013 |
url |
https://epic.awi.de/id/eprint/34183/ http://meetingorganizer.copernicus.org/EGU2013/EGU2013-10861.pdf https://hdl.handle.net/10013/epic.42481 |
long_lat |
ENVELOPE(-61.000,-61.000,-78.500,-78.500) |
geographic |
Antarctic Southern Ocean The Antarctic Weddell Sea Weddell Ronne Ice Shelf |
geographic_facet |
Antarctic Southern Ocean The Antarctic Weddell Sea Weddell Ronne Ice Shelf |
genre |
Antarc* Antarctic Filchner Ronne Ice Shelf Filchner-Ronne Ice Shelf Ice Shelf Ronne Ice Shelf Sea ice Southern Ocean Weddell Sea |
genre_facet |
Antarc* Antarctic Filchner Ronne Ice Shelf Filchner-Ronne Ice Shelf Ice Shelf Ronne Ice Shelf Sea ice Southern Ocean Weddell Sea |
op_source |
EPIC3European Geosciences Union General Assembly 2013, Vienna, 2013-04-07-2013-04-12Geophysical Research Abstracts |
op_relation |
Timmermann, R. and Hellmer, H. orcid:0000-0002-9357-9853 (2013) Southern Ocean warming and increased ice shelf basal melting in the 21st and 22nd centuries based on coupled ice-ocean finite-element modelling , European Geosciences Union General Assembly 2013, Vienna, 7 April 2013 - 12 April 2013 . hdl:10013/epic.42481 |
_version_ |
1766133720050302976 |