2023-07-25 10:41:00
The ULB glaciology laboratory took part in a study carried out by an international team of scientists, and published in the journal Science.
This new study shows that one-fifth of Greenland’s surface was deglaciated in the recent geological past, which may help understand the impact of current ice sheet melting and strengthen sea level rise projections.
It reveals that the perimeter of Greenland was, around 416,000 years ago, covered by a mixed landscape of ice, tundra and trees. The island was then roamed by woolly mammoths.
►Review||How long has Greenland been under ice? A ULB team scans the past of a previously green country (08/02/22)
►The ice cap had already disappeared a million years ago with a warming of 3°C (03/18/21)
New technics
The research was carried out on the basis of subglacial sediments from the first ice coring carried out in Greenland in the 1960s. To obtain these results and date the duration of deglaciation, the researchers used new techniques, including luminescence dating and cosmogenic nuclides.
The results of the study help to understand the stability of the Greenland Ice Sheet over the last two and a half million years, under climatic conditions similar to today’s : moderate warming with average global temperatures 1 to 1.5°C above pre-industrial values.
These conditions resulted in the melting of at least 20% of the total volume of the Greenland Ice Sheet. “The melting of Greenland then caused a rise of at least 1.5 meters in sea level, despite atmospheric carbon dioxide levels far below those of today. This tells us that the ice sheet is sensitive to human-caused climate change and will be vulnerable to rapid melting over the next few centuries.“, explains Belgian glaciologist Jean-Louis Tison (ULB), co-author of the study.
With Belgian
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