PARIS | The Greenland ice sheet has melted some 3.5 trillion tonnes in 10 years, raising ocean levels by one centimeter and increasing the risk of flooding around the world, according to a study released Monday.
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Second ice cap after Antarctica, with an area of nearly 1.8 million km2, the layer of ice covering Greenland is causing concern among scientists, while the warming in the Arctic is three times faster than elsewhere in the world. It contains in total enough to raise the oceans from 6 to 7 meters.
Many teams are scrutinizing its evolution, but the study published in the journal Nature Communications is the first to rely in particular on satellite observations from the European Space Agency and concludes that melting has increased by 21% in 40 years.
It has reached 3,500 billion tonnes since 2011, two-thirds of which in the summer of 2012 and 2019 alone, according to the study.
Satellite data have in fact revealed significant variations in the rate of melting, strongly accentuated by heat waves, even more than by gradual warming.
“Like elsewhere in the world, Greenland is vulnerable to the increase in extreme weather events,” said lead author Thomas Slater of the UK University of Leeds.
And satellite observation has made it possible to quickly and accurately estimate the loss in a given year and translate it into an impact on sea level rise, according to the researchers, who write that this method “will allow us to better understand the complex ice-melting processes ”.
“Model estimates suggest that the Greenlandic ice cap will help the oceans rise by between 3 and 23 centimeters by 2100,” said Amber Leeson of the British University of Lancaster and co-author of the study.