Oceanic forcing of ice-sheet retreat: West Antarctica and more

Richard B. Alley, Sridhar Anandakrishnan, Knut Christianson, Huw J. Horgan, Atsu Muto, Byron R. Parizek, David Pollard, Ryan T. Walker

Research output: Contribution to journalArticle

47 Scopus citations

Abstract

Ocean-ice interactions have exerted primary control on the Antarctic Ice Sheet and parts of the Greenland Ice Sheet, and will continue to do so in the near future, especially through melting of ice shelves and calving cliffs. Retreat in response to increasing marine melting typically exhibits threshold behavior, with little change for forcing below the threshold but a rapid, possibly delayed shift to a reduced state once the threshold is exceeded. For Thwaites Glacier, West Antarctica, the threshold may already have been exceeded, although rapid change may be delayed by centuries, and the reduced state will likely involve loss of most of the West Antarctic Ice Sheet, causing >3 m of sea-level rise. Because of shortcomings in physical understanding and available data, uncertainty persists about this threshold and the subsequent rate of change. Although sea-level histories and physical understanding allow the possibility that ice-sheet response could be quite fast, no strong constraints are yet available on the worst-case scenario. Recent work also suggests that the Greenland and East Antarctic Ice Sheets share some of the same vulnerabilities to shrinkage from marine influence.

Original languageEnglish (US)
Pages (from-to)207-231
Number of pages25
JournalAnnual Review of Earth and Planetary Sciences
Volume43
DOIs
StatePublished - May 30 2015

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All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Earth and Planetary Sciences (miscellaneous)
  • Space and Planetary Science

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