Evolution of Antarctic firn air content under three future warming scenarios
The Antarctic firn layer provides pore space in which an estimated 94 % to 96 % of the surface melt refreezes or is retained as liquid water. Future depletion of firn pore space by increased surface melt, densification and formation of low-permeability ice slabs can potentially lead to meltwater pon...
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ftcopernicus:oai:publications.copernicus.org:egusphere115138 2024-09-15T17:48:36+00:00 Evolution of Antarctic firn air content under three future warming scenarios Veldhuijsen, Sanne B. M. Berg, Willem Jan Kuipers Munneke, Peter Broeke, Michiel R. 2024-04-29 application/pdf https://doi.org/10.5194/egusphere-2023-2237 https://egusphere.copernicus.org/preprints/2023/egusphere-2023-2237/ eng eng doi:10.5194/egusphere-2023-2237 https://egusphere.copernicus.org/preprints/2023/egusphere-2023-2237/ eISSN: Text 2024 ftcopernicus https://doi.org/10.5194/egusphere-2023-2237 2024-08-28T05:24:15Z The Antarctic firn layer provides pore space in which an estimated 94 % to 96 % of the surface melt refreezes or is retained as liquid water. Future depletion of firn pore space by increased surface melt, densification and formation of low-permeability ice slabs can potentially lead to meltwater ponding, hydrofracturing and ice-shelf disintegration. Here, we investigate the 21st-century evolution of total firn air content (FAC) and accessible FAC (i.e. the pore space that meltwater can reach) across Antarctic ice shelves. We use the semi-empirical IMAU Firn Densification Model (IMAU-FDM) with an updated dynamical densification expression to cope with changing climate forcing. The firn model is forced by general circulation model output of the Community Earth System Model version 2 (CESM2) for three climate emission scenarios (SSP1-2.6, SSP2-4.5 and SSP5-8.5), dynamically downscaled to a 27 km horizontal resolution by the Regional Atmospheric Climate Model version 2.3p2 (RACMO2.3p2). To estimate accessible FAC, we prescribe a relationship between ice-slab thickness and permeability. In our simulations, ice shelves on the Antarctic Peninsula and the Roi Baudouin Ice Shelf in Dronning Maud Land are particularly vulnerable to total FAC depletion ( > 50 % decrease by 2100), even for low-emission (SSP1-2.6) and intermediate-emission (SSP2-4.5) scenarios. In the high-emission (SSP5-8.5) scenario in particular, the formation of ice slabs further reduces accessible FAC on ice shelves with low accumulation rates (current rates of < 500 mm w . e . yr - 1 <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="61pt" height="15pt" class="svg-formula" dspmath="mathimg" md5hash="b4c8699b596706f7bf9110e998ba2dca"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="tc-18-1983-2024-ie00001.svg" width="61pt" height="15pt" src="tc-18-1983-2024-ie00001.png"/> </svg:svg> ), including many East Antarctic ice shelves and the Filchner–Ronne, Ross, Pine Island and Larsen C ice shelves. These ... Text Antarc* Antarctic Antarctic Peninsula Dronning Maud Land Ice Shelf Ice Shelves Copernicus Publications: E-Journals |
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Copernicus Publications: E-Journals |
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English |
description |
The Antarctic firn layer provides pore space in which an estimated 94 % to 96 % of the surface melt refreezes or is retained as liquid water. Future depletion of firn pore space by increased surface melt, densification and formation of low-permeability ice slabs can potentially lead to meltwater ponding, hydrofracturing and ice-shelf disintegration. Here, we investigate the 21st-century evolution of total firn air content (FAC) and accessible FAC (i.e. the pore space that meltwater can reach) across Antarctic ice shelves. We use the semi-empirical IMAU Firn Densification Model (IMAU-FDM) with an updated dynamical densification expression to cope with changing climate forcing. The firn model is forced by general circulation model output of the Community Earth System Model version 2 (CESM2) for three climate emission scenarios (SSP1-2.6, SSP2-4.5 and SSP5-8.5), dynamically downscaled to a 27 km horizontal resolution by the Regional Atmospheric Climate Model version 2.3p2 (RACMO2.3p2). To estimate accessible FAC, we prescribe a relationship between ice-slab thickness and permeability. In our simulations, ice shelves on the Antarctic Peninsula and the Roi Baudouin Ice Shelf in Dronning Maud Land are particularly vulnerable to total FAC depletion ( > 50 % decrease by 2100), even for low-emission (SSP1-2.6) and intermediate-emission (SSP2-4.5) scenarios. In the high-emission (SSP5-8.5) scenario in particular, the formation of ice slabs further reduces accessible FAC on ice shelves with low accumulation rates (current rates of < 500 mm w . e . yr - 1 <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="61pt" height="15pt" class="svg-formula" dspmath="mathimg" md5hash="b4c8699b596706f7bf9110e998ba2dca"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="tc-18-1983-2024-ie00001.svg" width="61pt" height="15pt" src="tc-18-1983-2024-ie00001.png"/> </svg:svg> ), including many East Antarctic ice shelves and the Filchner–Ronne, Ross, Pine Island and Larsen C ice shelves. These ... |
format |
Text |
author |
Veldhuijsen, Sanne B. M. Berg, Willem Jan Kuipers Munneke, Peter Broeke, Michiel R. |
spellingShingle |
Veldhuijsen, Sanne B. M. Berg, Willem Jan Kuipers Munneke, Peter Broeke, Michiel R. Evolution of Antarctic firn air content under three future warming scenarios |
author_facet |
Veldhuijsen, Sanne B. M. Berg, Willem Jan Kuipers Munneke, Peter Broeke, Michiel R. |
author_sort |
Veldhuijsen, Sanne B. M. |
title |
Evolution of Antarctic firn air content under three future warming scenarios |
title_short |
Evolution of Antarctic firn air content under three future warming scenarios |
title_full |
Evolution of Antarctic firn air content under three future warming scenarios |
title_fullStr |
Evolution of Antarctic firn air content under three future warming scenarios |
title_full_unstemmed |
Evolution of Antarctic firn air content under three future warming scenarios |
title_sort |
evolution of antarctic firn air content under three future warming scenarios |
publishDate |
2024 |
url |
https://doi.org/10.5194/egusphere-2023-2237 https://egusphere.copernicus.org/preprints/2023/egusphere-2023-2237/ |
genre |
Antarc* Antarctic Antarctic Peninsula Dronning Maud Land Ice Shelf Ice Shelves |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Dronning Maud Land Ice Shelf Ice Shelves |
op_source |
eISSN: |
op_relation |
doi:10.5194/egusphere-2023-2237 https://egusphere.copernicus.org/preprints/2023/egusphere-2023-2237/ |
op_doi |
https://doi.org/10.5194/egusphere-2023-2237 |
_version_ |
1810290036829061120 |