Le Groenland perd plus de glace que prévu, selon une étude.
La fonte de la calotte glaciaire du Groenland, principalement due au réchauffement climatique, a été plus importante au cours des quatre dernières décennies que ce qui avait été estimé jusqu'à présent, selon une étude publiée mercredi qui se base sur l'analyse de données satellitaires.
Des chercheurs basés en Californie se sont penchés sur l'évolution de cette masse de glace, appelée aussi inlandsis, qui recouvre le territoire du Groenland.
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Des chercheurs basés en Californie se sont penchés sur l'évolution de cette masse de glace, appelée aussi inlandsis, qui recouvre le territoire du Groenland.
-
L'info en continu https://buzzplus.fr/
Infos, news & actualités - L'information internationale en direct.
Transcript
00:00 The melting of the Ice Cap of Greenland, mainly due to global warming,
00:04 has been more significant in the last four decades than what had been estimated until now,
00:09 according to a study published on Wednesday based on satellite data analysis.
00:13 Researchers based in California have been looking at the evolution of this mass of ice,
00:18 also called Inland-6, which covers Greenland.
00:22 Using satellite data, they have obtained nearly 240,000 observations of the positions of the ice fronts,
00:29 where the glaciers meet the ocean.
00:31 "What we found surprised us," said the scientists in the Nature magazine.
00:36 "The Ice Cap of Greenland has lost significantly more ice over the recent decades than what was thought before," they concluded.
00:44 Researchers have discovered that the mass of ice lost due to the retreat of the ice fronts
00:48 had historically been underestimated by a few thousand gigatons,
00:51 a gigaton corresponding to a billion tons,
00:54 the total loss would therefore be 20% higher than previous estimates.
00:58 "Almost every glacier in Greenland has shrunk or receded over the last few decades,"
01:03 said F.P. Chad Green, from the California Institute of Technology in Pasadena,
01:08 the main author of the study.
01:10 "There are no real exceptions and this happens everywhere at the same time," he said.
01:14 "The main cause of this melt is global warming,
01:18 whether it is global warming in the atmosphere or in the oceans,
01:21 the glaciers of Greenland are sensitive to both," said Green.
01:25 "The loss of mass had a direct minimal effect on the global rise in sea level,
01:29 the ice, which is mainly already in the sea," said the authors.
01:33 "However, it is sufficient to have a possible effect on ocean circulation,
01:38 with potential implications for climate regimes, ecosystems or food security,
01:44 as well as on the energy balance of the Earth."
01:46 Other discoveries
01:48 "The glaciers for which seasonal cycles of winter and summer retreat are the most marked
01:52 seem to be the most likely to react to warming
01:55 and have suffered the most marked retreat over the last decades.
01:58 This should allow us to predict more precisely
02:01 the future evolution of glaciers in the coming years. "