Influence of West Antarctic Ice Sheet collapse on Antarctic surface climate

• Published in: Geophysical research letters Vol. 42; no. 12; pp. 4862 - 4868
• Main Authors: Steig, Eric J., Huybers, Kathleen, Singh, Hansi A., Steiger, Nathan J., Ding, Qinghua, Frierson, Dargan M. W., Popp, Trevor, White, James W. C.
• Format: Journal Article
• Language: English
• Published: Washington Blackwell Publishing Ltd 28.06.2015; John Wiley & Sons, Inc
• Subjects: Advection; Anomalies; Antarctic climate; Antarctic ice; Antarctic ice sheet; Antarctica; atmospheric circulation; Banks (topography); Circulation; Climate; Climate models; Coastal; Collapse; Computer simulation; Cooling; Cyclonic circulation; Geophysics; Glaciation; glaciology; Global warming; Ice; Ice ages; ice core; Ice cores; Ice sheets; Interglacial periods; Isotopes; Land; Marine; Oxygen; Oxygen isotopes; Plateaus; Records; Sea level; Slope; South Pole; Topography; Topography (geology); Ross Sea; South Pole; PSW, Antarctica, West Antarctica; PSW, Antarctica, Marie Byrd Land; PSE, Antarctica, East Antarctica; Antarctica, South Pole; Antarctica, West Antarctica, West Antarctic Ice Sheet; PS, Ross Sea
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1002/2015GL063861

Climate model simulations are used to examine the impact of a collapse of the West Antarctic Ice Sheet (WAIS) on the surface climate of Antarctica. The lowered topography following WAIS collapse produces anomalous cyclonic circulation with increased flow of warm, maritime air toward the South Pole and cold‐air advection from the East Antarctic plateau toward the Ross Sea and Marie Byrd Land, West Antarctica. Relative to the background climate, areas in East Antarctica that are adjacent to the WAIS warm, while substantial cooling (several ∘C) occurs over parts of West Antarctica. Anomalously low isotope‐paleotemperature values at Mount Moulton, West Antarctica, compared with ice core records in East Antarctica, are consistent with collapse of the WAIS during the last interglacial period, Marine Isotope Stage 5e. More definitive evidence might be recoverable from an ice core record at Hercules Dome, East Antarctica, which would experience significant warming and positive oxygen isotope anomalies if the WAIS collapsed. Key Points Collapse of the West Antarctic Ice Sheet would change atmospheric circulation over Antarctica WAIS collapse warms adjacent areas of East Antarctica and cools coastal Marie Byrd Land Ice core data provide supporting evidence for WAIS collapse during the last interglacial period (MIS 5e)