Meltwater produced by wind–albedo interaction stored in an East Antarctic ice shelf


Contact
Olaf.Eisen [ at ] awi.de

Abstract

Surface melt and subsequent firn air depletion can ultimately lead to disintegration of Antarctic ice shelves1,2 causing grounded glaciers to accelerate3 and sea level to rise. In the Antarctic Peninsula, foehn winds enhance melting near the grounding line4, which in the recent past has led to the disintegration of the most northerly ice shelves5,6. Here, we provide observational and model evidence that this process also occurs over an East Antarctic ice shelf, where meltwaterinduced firn air depletion is found in the grounding zone. Unlike the Antarctic Peninsula, where foehn events originate from episodic interaction of the circumpolar westerlies with the topography, in coastal East Antarctica high temperatures are caused by persistent katabatic winds originating from the ice sheet’s interior. Katabatic winds warm and mix the air as it flows downward and cause widespread snow erosion, explaining >3 K higher near-surface temperatures in summer and surface melt doubling in the grounding zone compared with its surroundings. Additionally, these winds expose blue ice and firn with lower surface albedo, further enhancing melt. The in situ observation of supraglacial flow and englacial storage of meltwater suggests that ice-shelf grounding zones in East Antarctica, like their Antarctic Peninsula counterparts, are vulnerable to hydrofracturing7.



Item Type
Article
Authors
Divisions
Primary Division
Programs
Primary Topic
Publication Status
Published
Eprint ID
42771
DOI 10.1038/NCLIMATE3180

Cite as
Lenaerts, J. T. M. , Lhermitte, S. , Drews, R. , Ligtenberg, S. R. M. , Berger, S. , Helm, V. , Smeets, C. J. P. P. , Broeke, M. R. v. d. , van de Berg, W. J. , van Meijgaard, E. , Eijkelboom, M. , Eisen, O. and Pattyn, F. (2017): Meltwater produced by wind–albedo interaction stored in an East Antarctic ice shelf , Nature Climate Change, 7 , pp. 58-63 . doi: 10.1038/NCLIMATE3180


Download
[thumbnail of Lenaerts_etal_2016-Nature_Climate_Change_meltwater.pdf]
Preview
PDF
Lenaerts_etal_2016-Nature_Climate_Change_meltwater.pdf

Download (7MB) | Preview
Cite this document as:

Share
Add to AnyAdd to TwitterAdd to FacebookAdd to LinkedinAdd to PinterestAdd to Email


Citation

Geographical region

Research Platforms

Campaigns
N/A


Actions
Edit Item Edit Item