Researchers report estimates of the Antarctic Ice Sheet mass balance over the past four decades. Ice sheet mass balance--the net gain or loss of ice mass--can be estimated by comparing ice accumulation via snowfall with ice loss via discharge from glaciers, sublimation, and wind erosion. Eric Rignot and colleagues combined satellite data records with climate model outputs to estimate the Antarctic Ice Sheet mass balance from 1979 to 2017. During this time, the estimated rate of mass loss increased from 40 Gt/yr in the 1980s to more than 250 Gt/yr in the 2010s, with a majority of the recent loss coming from West Antarctica. The authors estimated that since 1979, West Antarctica, East Antarctica, and the Antarctic Peninsula have contributed 6.9 mm, 4.4 mm, and 2.5 mm to sea level rise, respectively. The results indicate that East Antarctica, particularly Wilkes Land, has been a significant contributor to sea level rise over the past four decades, suggesting the need for greater attention to this part of Antarctica. The regions contributing to Antarctic mass loss are associated with warm, salty circumpolar deep water (CDW). The increasing mass loss over time is consistent with strengthening and contraction of the polar westerlies, which increases the amount of CDW in contact with the glaciers, according to the authors.
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Article #18-12883: "Four decades of Antarctic Ice Sheet mass balance from 1979-2017," by Eric Rignot et al.
MEDIA CONTACT: Eric Rignot, University of California, Irvine, CA; tel: 949-824-3739, 818-653-2531; e-mail: erignot@uci.edu
Journal
Proceedings of the National Academy of Sciences