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Title: Responses of the Pine Island and Thwaites glaciers to melt and sliding parameterizations
The Pine Island and Thwaites glaciers are the two largest contributors to sea level rise from Antarctica. Here we examine the influence of basal friction and ice shelf basal melt in determining projected losses. We examine both Weertman and Coulomb friction laws with explicit weakening as the ice thins to flotation, which many friction laws include implicitly via the effective pressure. We find relatively small differences with the choice of friction law (Weertman or Coulomb) but find losses to be highly sensitive to the rate at which the basal traction is reduced as the area upstream of the grounding line thins. Consistent with earlier work on Pine Island Glacier, we find sea level contributions from both glaciers to vary linearly with the melt volume averaged over time and space, with little influence from the spatial or temporal distribution of melt. Based on recent estimates of melt from other studies, our simulations suggest that the combined melt-driven and sea level rise contribution from both glaciers may not exceed 10 cm by 2200, although the uncertainty in model parameters allows for larger increases. We do not include other factors, such as ice shelf breakup, that might increase loss, or factors such as increased accumulation and isostatic uplift that may mitigate loss.  more » « less
Award ID(s):
1835321
PAR ID:
10557904
Author(s) / Creator(s):
; ;
Publisher / Repository:
Copernicus GmbH
Date Published:
Journal Name:
The Cryosphere
Volume:
18
Issue:
5
ISSN:
1994-0424
Page Range / eLocation ID:
2583 to 2601
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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