Greenland’s Surface Also to Show Net Ice Loss at Global Temperatures Above ~2.5°C

Geophysical Research Letters, January 19

Greenland has been losing mass and contributing to sea-level rise since the 1980’s, according to most studies, with most of this loss occurring through calving of icebergs where glaciers running from the ice sheet meet the ocean. Melting of the surface of the ice sheet each summer however is largely offset by snowfall during the winter.  This study found however that at global temperatures of 2.7°C, which could be reached by mid-century if current emissions continue, even the surface of Greenland will reach a threshold where summer melt is no longer offset by winter snowfall, with further acceleration of Greenland’s contribution to sea-level rise.  Surface melt alone under such high emissions scenarios would contribute an added 13 cm to global sea-level rise from Greenland by 2100, with continued acceleration thereafter.  At that point also, Greenland will begin losing altitude, eventually resulting in the ice sheet’s lowering to a point where above-freezing temperatures occur for longer periods each year, until near-complete ice sheet loss becomes inevitable.

https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020GL090471

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