Climate Change and Forest Fires Synergistically Drive Widespread Melt Events of the Greenland Ice Sheet

In July 2012, over 97% of the Greenland Ice Sheet experienced surface melt, the first widespread melt during the era of satellite remote sensing. Analysis of six Greenland shallow firn cores from the dry snow region confirms that the most recent prior widespread melt occurred in 1889. A firn core fr...

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Bibliographic Details
Published in:Proceedings of the National Academy of Sciences
Main Authors: Keegan, Kaitlin M, Albert, Mary R, McConnell, Joseph R, Baker, Ian
Format: Text
Language:unknown
Published: Dartmouth Digital Commons 2014
Subjects:
Online Access:https://digitalcommons.dartmouth.edu/facoa/1617
https://doi.org/10.1073/pnas.1405397111
https://digitalcommons.dartmouth.edu/context/facoa/article/2620/viewcontent/ptpmcrender.fcgi
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Summary:In July 2012, over 97% of the Greenland Ice Sheet experienced surface melt, the first widespread melt during the era of satellite remote sensing. Analysis of six Greenland shallow firn cores from the dry snow region confirms that the most recent prior widespread melt occurred in 1889. A firn core from the center of the ice sheet demonstrated that exceptionally warm temperatures combined with black carbon sediments from Northern Hemisphere forest fires reduced albedo below a critical threshold in the dry snow region, and caused the melting events in both 1889 and 2012. We use these data to project the frequency of widespread melt into the year 2100. Since Arctic temperatures and the frequency of forest fires are both expected to rise with climate change, our results suggest that widespread melt events on the Greenland Ice Sheet may begin to occur almost annually by the end of century. These events are likely to alter the surface mass balance of the ice sheet, leaving the surface susceptible to further melting.