Environment & Energy

Glacier recession around the Greenland Ice Sheet

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From 1990 to 2000, the mass loss was 41 ± 17 Gt/year, and from 2000 to 2010 it was 187 ± 17 Gt/yr. From 2010 to 2018, it was losing 286 ± 20 Gt/yr (Mouginot et al., 2019). This means that there has been a six-fold increase in mass loss since the 1980s (Mouginot et al., 2019).

In total, since 1972, the Greenland Ice Sheet has contributed 13.7 ± 1.1 mm to global sea level rise. Half of this sea level contribution was in the period of 2010-2018.

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What is causing these changes?

In Greenland, around half of the mass loss is now due to meltwater runoff during warm summers (Slater et al., 2021). Since the year 2000,increasing surface melt has accounted to a larger proportion of the ice sheet mass loss (Mouginot et al., 2019).

The remaining ice loss is due to increased calving of icebergs at the edges of the largest ice streams draining the ice sheet (like Jakoshavn Isbrae and Humboldt Glacier). This increased calving means that the amount of ice being lost from the ice sheet to the ocean is increasing, and ice flow is increasing (Howat et al., 2008). The increase in ice discharge at these outlet glaciers has been related to a warming of the subsurface waters around the ice sheet from the end of the 1990s onwards (Mouginot et al., 2021).


Glacier names in Greenland, from Polar Portal.

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