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View from the Syd Glacier to the Bowdoin Fjord in northwest Greenland

Photo: Mark Smith / AAAS

Once all you could see here was ice and snow, but now you can see bushes, rocks and wetlands instead: almost 29,000 square kilometers of Greenland's ice sheet and glaciers melted from the 1980s to the 2010s. This is the result of historical satellite data that researchers at the University of Leeds evaluated and which were published on Tuesday in the journal “Scientific Reports”.

The melted area accounts for around 1.6 percent of Greenland's total ice and glacier area and is roughly the size of Albania, according to the press release from the University of Leeds. In total, Greenland is around 2.1 million square kilometers in size, making it the largest island in the world. Global warming is progressing particularly quickly here: the average annual air temperatures between 2007 and 2012 were 3 degrees higher than between 1979 and 2000, the researchers write.

The reason for this is the phenomenon of “Arctic amplification”. Ice and snow reflect sunlight because of their bright surface - but when they melt, the resulting dark seawater absorbs more heat than ice and snow would have. This causes even more ice to thaw or freeze later in the fall. The darker surface continues to expand.

Greenland is getting greener

According to the study's authors, the area on which vegetation grew increased by more than 87,000 square kilometers over the three decades examined, making it more than twice as large. The number of Greenland wetlands has almost quadrupled, particularly in the east and northeast. The expansion of vegetation indicates that the permafrost is thawing, the researchers write in the study. As a result, greenhouse gases that were previously stored in these Arctic soils escaped into the atmosphere.

According to Michael Grimes, lead author of the study, the spread of vegetation in turn impacts the flow of sediment and nutrients in coastal waters. “These changes are critical, especially for the indigenous population, whose traditional hunting practices depend on the stability of these sensitive ecosystems,” says Grimes. "In addition, the loss of ice mass in Greenland contributes significantly to global sea level rise." In the last 20 years alone, sea level has risen by an average of 1.2 centimeters worldwide due to thawing ice in Greenland.

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