Ocean temperature thresholds for Last Interglacial West Antarctic Ice Sheet collapse
The West Antarctic Ice Sheet (WAIS) is considered the major contributor to global sea level rise in the Last Interglacial (LIG) and potentially in the future. Exposed fossil reef terraces suggest sea levels in excess of 7 meters in the last warm era, of which probably not much more than 2 meters are...
| Published in: | Geophysical Research Letters |
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| Main Authors: | , , , , |
| Format: | Article in Journal/Newspaper |
| Language: | unknown |
| Published: |
Wiley
2016
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| Subjects: | |
| Online Access: | https://epic.awi.de/id/eprint/39767/ https://epic.awi.de/id/eprint/39767/1/grl53983.pdf http://onlinelibrary.wiley.com/doi/10.1002/2016GL067818/pdf https://hdl.handle.net/10013/epic.46901 https://hdl.handle.net/10013/epic.46901.d001 |
| Summary: | The West Antarctic Ice Sheet (WAIS) is considered the major contributor to global sea level rise in the Last Interglacial (LIG) and potentially in the future. Exposed fossil reef terraces suggest sea levels in excess of 7 meters in the last warm era, of which probably not much more than 2 meters are considered to originate from melting of the Greenland Ice Sheet. We simulate the evolution of the Antarctic Ice Sheet during the LIG with a 3D thermomechanical ice sheet model forced by an atmosphere ocean general circulation model (AOGCM). Our results show that high LIG sea levels, cannot be reproduced with the atmosphere-ocean forcing delivered by current AOGCMs. However, when taking reconstructed Southern Ocean temperature anomalies of several degrees, sensitivity studies indicate a Southern Ocean temperature anomaly threshold for total WAIS collapse of 2-3∘C, accounting for a sea level rise of 3-4 meters during the LIG. Potential future Antarctic Ice Sheet dynamics range from a moderate retreat to a complete collapse, depending on rate and amplitude of warming. |
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