Apr 22, 2016

Has Arctic Sea Ice Loss Contributed to Increased Surface Melting of the Greenland Ice Sheet?

by
Jiping Liu, Zhiqiang Chen, Jennifer Francis, Mirong Song, Thomas Mote, and Yongyun Hu
,
American Meteorological Society
  • Shows that an important contributing factor of increased surface melt of the Greenland ice sheet is the decreasing Arctic sea ice
  • Finds reduced summer sea ice favors stronger and more frequent occurrences of blocking-high pressure events over Greenland
  • Finds blocking highs enhance the transport of warm, moist air over Greenland, which increases downwelling infrared radiation, contributes to increased extreme heat events, and accounts for the majority of the observed warming trends
  • States these findings are supported by analyses of observations and reanalysis data, as well as by independent atmospheric model simulations using a state-of-the-art atmospheric model that is forced by varying only the sea ice conditions
  • Statess reduced sea ice conditions in the model favor more extensive Greenland surface melting
  • Finds a positive feedback between the variability in the extent of summer Arctic sea ice and melt area of the summer Greenland ice sheet, which affects the Greenland ice sheet mass balance
  • Holds that this linkage may improve the projections of changes in the global sea level and thermohaline circulation