Observed rapid bedrock uplift in amundsen sea embayment promotes ice-sheet stability
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.
Barletta, V., Bevis, M., Smith, B., Wilson, T., Brown, A., Bordoni, A., Willis, M., & Khan, S. (2018). Observed rapid bedrock uplift in amundsen sea embayment promotes ice-sheet stability. Science, 360 (6395), 1335-1339. https://doi.org/10.1126/science.aao1447