Total isostatic response to the complete unloading of the Greenland and Antarctic Ice Sheets
Abstract The land surface beneath the Greenland and Antarctic Ice Sheets is isostatically suppressed by the mass of the overlying ice. Accurate computation of the land elevation in the absence of ice is important when considering, for example, regional geodynamics, geomorphology, and ice sheet behav...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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Nature Portfolio
2022-07-01
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| Series: | Scientific Reports |
| Online Access: | https://doi.org/10.1038/s41598-022-15440-y |
| _version_ | 1811323707219509248 |
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| author | Guy J. G. Paxman Jacqueline Austermann Andrew Hollyday |
| author_facet | Guy J. G. Paxman Jacqueline Austermann Andrew Hollyday |
| author_sort | Guy J. G. Paxman |
| collection | DOAJ |
| description | Abstract The land surface beneath the Greenland and Antarctic Ice Sheets is isostatically suppressed by the mass of the overlying ice. Accurate computation of the land elevation in the absence of ice is important when considering, for example, regional geodynamics, geomorphology, and ice sheet behaviour. Here, we use contemporary compilations of ice thickness and lithospheric effective elastic thickness to calculate the fully re-equilibrated isostatic response of the solid Earth to the complete removal of the Greenland and Antarctic Ice Sheets. We use an elastic plate flexure model to compute the isostatic response to the unloading of the modern ice sheet loads, and a self-gravitating viscoelastic Earth model to make an adjustment for the remaining isostatic disequilibrium driven by ice mass loss since the Last Glacial Maximum. Feedbacks arising from water loading in areas situated below sea level after ice sheet removal are also taken into account. In addition, we quantify the uncertainties in the total isostatic response associated with a range of elastic and viscoelastic Earth properties. We find that the maximum change in bed elevation following full re-equilibration occurs over the centre of the landmasses and is +783 m in Greenland and +936 m in Antarctica. By contrast, areas around the ice margins experience up to 123 m of lowering due to a combination of sea level rise, peripheral bulge collapse, and water loading. The computed isostatic response fields are openly accessible and have a number of applications for studying regional geodynamics, landscape evolution, cryosphere dynamics, and relative sea level change. |
| first_indexed | 2024-04-13T14:00:10Z |
| format | Article |
| id | doaj.art-9d61e188bf234d0c89504772ebeb7d0e |
| institution | Directory Open Access Journal |
| issn | 2045-2322 |
| language | English |
| last_indexed | 2024-04-13T14:00:10Z |
| publishDate | 2022-07-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Scientific Reports |
| spelling | doaj.art-9d61e188bf234d0c89504772ebeb7d0e2022-12-22T02:44:04ZengNature PortfolioScientific Reports2045-23222022-07-0112111010.1038/s41598-022-15440-yTotal isostatic response to the complete unloading of the Greenland and Antarctic Ice SheetsGuy J. G. Paxman0Jacqueline Austermann1Andrew Hollyday2Lamont-Doherty Earth Observatory of Columbia UniversityLamont-Doherty Earth Observatory of Columbia UniversityLamont-Doherty Earth Observatory of Columbia UniversityAbstract The land surface beneath the Greenland and Antarctic Ice Sheets is isostatically suppressed by the mass of the overlying ice. Accurate computation of the land elevation in the absence of ice is important when considering, for example, regional geodynamics, geomorphology, and ice sheet behaviour. Here, we use contemporary compilations of ice thickness and lithospheric effective elastic thickness to calculate the fully re-equilibrated isostatic response of the solid Earth to the complete removal of the Greenland and Antarctic Ice Sheets. We use an elastic plate flexure model to compute the isostatic response to the unloading of the modern ice sheet loads, and a self-gravitating viscoelastic Earth model to make an adjustment for the remaining isostatic disequilibrium driven by ice mass loss since the Last Glacial Maximum. Feedbacks arising from water loading in areas situated below sea level after ice sheet removal are also taken into account. In addition, we quantify the uncertainties in the total isostatic response associated with a range of elastic and viscoelastic Earth properties. We find that the maximum change in bed elevation following full re-equilibration occurs over the centre of the landmasses and is +783 m in Greenland and +936 m in Antarctica. By contrast, areas around the ice margins experience up to 123 m of lowering due to a combination of sea level rise, peripheral bulge collapse, and water loading. The computed isostatic response fields are openly accessible and have a number of applications for studying regional geodynamics, landscape evolution, cryosphere dynamics, and relative sea level change.https://doi.org/10.1038/s41598-022-15440-y |
| spellingShingle | Guy J. G. Paxman Jacqueline Austermann Andrew Hollyday Total isostatic response to the complete unloading of the Greenland and Antarctic Ice Sheets Scientific Reports |
| title | Total isostatic response to the complete unloading of the Greenland and Antarctic Ice Sheets |
| title_full | Total isostatic response to the complete unloading of the Greenland and Antarctic Ice Sheets |
| title_fullStr | Total isostatic response to the complete unloading of the Greenland and Antarctic Ice Sheets |
| title_full_unstemmed | Total isostatic response to the complete unloading of the Greenland and Antarctic Ice Sheets |
| title_short | Total isostatic response to the complete unloading of the Greenland and Antarctic Ice Sheets |
| title_sort | total isostatic response to the complete unloading of the greenland and antarctic ice sheets |
| url | https://doi.org/10.1038/s41598-022-15440-y |
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