Observed rapid bedrock uplift in Amundsen Sea Embayment promotes ice-sheet stability (original) (raw)
ADS
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- Bevis, Michael ;
- Smith, Benjamin E. ;
- Wilson, Terry ;
- Brown, Abel ;
- Bordoni, Andrea ;
- Willis, Michael ;
- Khan, Shfaqat Abbas ;
- Rovira-Navarro, Marc ;
- Dalziel, Ian ;
- Smalley, Robert ;
- Kendrick, Eric ;
- Konfal, Stephanie ;
- Caccamise, Dana J. ;
- Aster, Richard C. ;
- Nyblade, Andy ;
- Wiens, Douglas A.
Abstract
The marine portion of the West Antarctic Ice Sheet (WAIS) in the Amundsen Sea Embayment (ASE) accounts for one-fourth of the cryospheric contribution to global sea-level rise and is vulnerable to catastrophic collapse. The bedrock response to ice mass loss, glacial isostatic adjustment (GIA), was thought to occur on a time scale of 10,000 years. We used new GPS measurements, which show a rapid (41 millimeters per year) uplift of the ASE, to estimate the viscosity of the mantle underneath. We found a much lower viscosity (4 × 1018 pascal-second) than global average, and this shortens the GIA response time scale to decades up to a century. Our finding requires an upward revision of ice mass loss from gravity data of 10% and increases the potential stability of the WAIS against catastrophic collapse.
Publication:
Science
Pub Date:
June 2018
DOI:
Bibcode: