Greenland ice sheet: Feedback loop amplified ice melt from warm weather

Greenland ice sheet: Feedback loop amplified ice melt from warm weather

June 17, 2022 0 By bimola

Last August, rain fell for the first time at the peak of Greenland’s ice sheet, but this had little impact on ice melt compared with other effects



Environment



17 June 2022

For the first time ever recorded, in the late summer of 2021, rain fell on the high central region of the Greenland ice sheet. This extraordinary event was followed by the surface snow and ice rapidly melting. Researchers discovered that it wasn?t the rain that caused the melt, it was unusually warm ?atmospheric rivers? that swept along Greenland, bringing potent melt conditions when the melt season would normally be drawing to a close. Thanks to detailed measurements from the network of automatic weather stations on the ice set up by the Department of Glaciology and Climate at the Geological Survey of Denmark and Greenland coupled with measurements from the Copernicus Sentinel-3 satellites in space helped researchers understand the exact processes and dynamics of how the ice melts.

A weather station on the Greenland ice sheet

GEUS/ESA

When rain fell for the first time at the highest point of Greenland’s ice sheet last August, it marked a significant climate change milestone. But researchers have now revealed in unprecedented detail how an accompanying plume of hot air had a far bigger impact by melting snow, with the rain only playing a minor role.

The snow melt created a feedback loop by exposing darker ice, which absorbs more heat and causes more snow to melt in turn. Events like this will …