Talk by Prof. Eric Steig, Earth & Space Sci.
Influence of the collapse of the West Antarctic Ice Sheet on Antarctic
climate and ice core records, and possible evidence for collapse during the last interglacial period.
We conducted climate-model simulations of the atmospheric response to a
collapse of the West Antarctic Ice Sheet (WAIS). The lowered topography
following WAIS collapse produces anomalous cyclonic circulation, with
increased flow of warm, maritime air towards the South Pole from the
Amundsen-Bellingshausen Seas, and cold-air advection from the East
Antarctic plateau towards Marie Byrd Land, West Antarctica. Relative to
the background climate, some areas in the East Antarctic interior warm
moderately, while substantial cooling (several ◦C) occurs over parts of
Marie Byrd Land. Differences between isotope-paleotemperature anomalies
for the last interglacial period from existing ice core paleoclimate
records in East and West Antarctica can largely be explained by the
climate response to WAIS collapse. More definitive evidence could be
obtained from an ice core record at Hercules Dome, East Antarctica,
which would record significant warming if WAIS collapse occurred during
the last interglacial period. There is also a global response to WAIS
collapse including slight cooling over Greenland!