Evolving understanding of Antarctic ice-sheet physics and ambiguity in probabilistic sea-level projections
Mechanisms such as ice-shelf hydrofracturing and ice-cliff collapse may rapidly increase discharge from marine-based ice sheets. Here, we link a probabilistic framework for sea-level projections to a small ensemble of Antarctic ice-sheet (AIS) simulations incorporating these physical processes to ex...
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ftdatacite:10.48550/arxiv.1704.05597 2023-05-15T13:33:30+02:00 Evolving understanding of Antarctic ice-sheet physics and ambiguity in probabilistic sea-level projections Kopp, Robert E. DeConto, Robert M. Bader, Daniel A. Hay, Carling C. Horton, Radley M. Kulp, Scott Oppenheimer, Michael Pollard, David Strauss, Benjamin H. 2017 https://dx.doi.org/10.48550/arxiv.1704.05597 https://arxiv.org/abs/1704.05597 unknown arXiv https://dx.doi.org/10.1002/2017ef000663 arXiv.org perpetual, non-exclusive license http://arxiv.org/licenses/nonexclusive-distrib/1.0/ Atmospheric and Oceanic Physics physics.ao-ph FOS Physical sciences article-journal Article ScholarlyArticle Text 2017 ftdatacite https://doi.org/10.48550/arxiv.1704.05597 https://doi.org/10.1002/2017ef000663 2022-04-01T10:53:31Z Mechanisms such as ice-shelf hydrofracturing and ice-cliff collapse may rapidly increase discharge from marine-based ice sheets. Here, we link a probabilistic framework for sea-level projections to a small ensemble of Antarctic ice-sheet (AIS) simulations incorporating these physical processes to explore their influence on global-mean sea-level (GMSL) and relative sea-level (RSL). We compare the new projections to past results using expert assessment and structured expert elicitation about AIS changes. Under high greenhouse gas emissions (Representative Concentration Pathway [RCP] 8.5), median projected 21st century GMSL rise increases from 79 to 146 cm. Without protective measures, revised median RSL projections would by 2100 submerge land currently home to 153 million people, an increase of 44 million. The use of a physical model, rather than simple parameterizations assuming constant acceleration of ice loss, increases forcing sensitivity: overlap between the central 90% of simulations for 2100 for RCP 8.5 (93-243 cm) and RCP 2.6 (26-98 cm) is minimal. By 2300, the gap between median GMSL estimates for RCP 8.5 and RCP 2.6 reaches >10 m, with median RSL projections for RCP 8.5 jeopardizing land now occupied by 950 million people (vs. 167 million for RCP 2.6). The minimal correlation between the contribution of AIS to GMSL by 2050 and that in 2100 and beyond implies current sea-level observations cannot exclude future extreme outcomes. The sensitivity of post-2050 projections to deeply uncertain physics highlights the need for robust decision and adaptive management frameworks. : 20 pages, 6 figures (main text); 13 pages, 11 figures (supporting information) Text Antarc* Antarctic Ice Sheet Ice Shelf DataCite Metadata Store (German National Library of Science and Technology) Antarctic |
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DataCite Metadata Store (German National Library of Science and Technology) |
op_collection_id |
ftdatacite |
language |
unknown |
topic |
Atmospheric and Oceanic Physics physics.ao-ph FOS Physical sciences |
spellingShingle |
Atmospheric and Oceanic Physics physics.ao-ph FOS Physical sciences Kopp, Robert E. DeConto, Robert M. Bader, Daniel A. Hay, Carling C. Horton, Radley M. Kulp, Scott Oppenheimer, Michael Pollard, David Strauss, Benjamin H. Evolving understanding of Antarctic ice-sheet physics and ambiguity in probabilistic sea-level projections |
topic_facet |
Atmospheric and Oceanic Physics physics.ao-ph FOS Physical sciences |
description |
Mechanisms such as ice-shelf hydrofracturing and ice-cliff collapse may rapidly increase discharge from marine-based ice sheets. Here, we link a probabilistic framework for sea-level projections to a small ensemble of Antarctic ice-sheet (AIS) simulations incorporating these physical processes to explore their influence on global-mean sea-level (GMSL) and relative sea-level (RSL). We compare the new projections to past results using expert assessment and structured expert elicitation about AIS changes. Under high greenhouse gas emissions (Representative Concentration Pathway [RCP] 8.5), median projected 21st century GMSL rise increases from 79 to 146 cm. Without protective measures, revised median RSL projections would by 2100 submerge land currently home to 153 million people, an increase of 44 million. The use of a physical model, rather than simple parameterizations assuming constant acceleration of ice loss, increases forcing sensitivity: overlap between the central 90% of simulations for 2100 for RCP 8.5 (93-243 cm) and RCP 2.6 (26-98 cm) is minimal. By 2300, the gap between median GMSL estimates for RCP 8.5 and RCP 2.6 reaches >10 m, with median RSL projections for RCP 8.5 jeopardizing land now occupied by 950 million people (vs. 167 million for RCP 2.6). The minimal correlation between the contribution of AIS to GMSL by 2050 and that in 2100 and beyond implies current sea-level observations cannot exclude future extreme outcomes. The sensitivity of post-2050 projections to deeply uncertain physics highlights the need for robust decision and adaptive management frameworks. : 20 pages, 6 figures (main text); 13 pages, 11 figures (supporting information) |
format |
Text |
author |
Kopp, Robert E. DeConto, Robert M. Bader, Daniel A. Hay, Carling C. Horton, Radley M. Kulp, Scott Oppenheimer, Michael Pollard, David Strauss, Benjamin H. |
author_facet |
Kopp, Robert E. DeConto, Robert M. Bader, Daniel A. Hay, Carling C. Horton, Radley M. Kulp, Scott Oppenheimer, Michael Pollard, David Strauss, Benjamin H. |
author_sort |
Kopp, Robert E. |
title |
Evolving understanding of Antarctic ice-sheet physics and ambiguity in probabilistic sea-level projections |
title_short |
Evolving understanding of Antarctic ice-sheet physics and ambiguity in probabilistic sea-level projections |
title_full |
Evolving understanding of Antarctic ice-sheet physics and ambiguity in probabilistic sea-level projections |
title_fullStr |
Evolving understanding of Antarctic ice-sheet physics and ambiguity in probabilistic sea-level projections |
title_full_unstemmed |
Evolving understanding of Antarctic ice-sheet physics and ambiguity in probabilistic sea-level projections |
title_sort |
evolving understanding of antarctic ice-sheet physics and ambiguity in probabilistic sea-level projections |
publisher |
arXiv |
publishDate |
2017 |
url |
https://dx.doi.org/10.48550/arxiv.1704.05597 https://arxiv.org/abs/1704.05597 |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic Ice Sheet Ice Shelf |
genre_facet |
Antarc* Antarctic Ice Sheet Ice Shelf |
op_relation |
https://dx.doi.org/10.1002/2017ef000663 |
op_rights |
arXiv.org perpetual, non-exclusive license http://arxiv.org/licenses/nonexclusive-distrib/1.0/ |
op_doi |
https://doi.org/10.48550/arxiv.1704.05597 https://doi.org/10.1002/2017ef000663 |
_version_ |
1766042965315158016 |