The Arctic is warming faster than expected – Le Figaro

Warming in the North Pole region would exceed all estimates. An alarming finding linked to the phenomenon of Arctic amplification. The Arctic has warmed nearly four times faster than the rest of the world in the past 40 years: these conclusions of a new study raise fears of an underestimation of the models climatic conditions of the poles, the warming of which has a major influence on the rise in sea levels. North. In 2019, the United Nations (IPCC) panel of climate experts estimated that the Arctic was warming “more than twice the global average”, as a result of a specific process in the region. This phenomenon, called “Arctic amplification”, occurs when sea ice and snow, which naturally reflect the sun’s heat, melt into seawater which absorbs more solar radiation and heats up. ice is accelerating in all regions of the planet»SEE ALSO – More skiing at the Stelvio glacier after the heat wave in ItalyIf scientists have long agreed on the observation of an accelerated warming of the Arctic, their estimates of the However, this phenomenon diverges according to the period they choose to study or the definition, more or less extensive, of the geographical area of ​​the Arctic. In the new study, the researchers, based in Norway and Finland, analyzed four sets of temperature data collected across the Arctic Circle by satellites since 1979 – the year satellite data first became available. They concluded that the Arctic has warmed by an average of 0.75°C per decade, nearly four times faster than the rest of the planet. Due to greenhouse gases generated by human activities, mainly by fossil fuels, the planet has already gained almost 1.2°C since the pre-industrial era. “The scientific literature considers that the Arctic is warming about twice as fast as the rest of the planet, so I was surprised that our conclusion was much higher than the usual figure,” Antti Lipponen told AFP. member of the Finnish Meteorological Institute and co-author of the study. However, the study found large local variations in the rate of warming within the Arctic Circle. For example, the Eurasian sector of the Arctic Ocean, near the Norwegian archipelago of Svalbard and the Russian one of Novaya Zemlya, has warmed by 1.25 C° per decade, about seven times faster than the rest. of the world. Melting ice sheet The team found that the most advanced climate models projected Arctic warming about a third lower than what their own data shows. This discrepancy, according to them, could be explained by the obsolescence of previous models of the Arctic climate, which are constantly being improved. “Maybe the next step would be to take a look at these models, see why they don’t predict what we see in observations and what impact that has on future climate projections,” Antti Lipponen said. The intense warming of the Arctic, in addition to a serious impact on the inhabitants and on the local fauna, which depends on the continuity of the sea ice to hunt, will also have global repercussions. “Climate change is man-made and as the Arctic warms, its glaciers will melt, which will affect global sea levels,” said Antii Lipponen. “Something is happening in the Arctic and it will affect us all,” he worries. sea ​​level rise, melting glaciers and expanding oceans due to warming water. The melting of the pack ice (ice on the oceans) does not raise the sea level. According to the IPCC, the sea level has risen by 20 cm since 1900. However, the rate of this rise has almost tripled since 1990 and, depending on the scenario, the oceans could gain another 40 to 85 cm by the end of the century. The Greenland Ice Sheet, which recent studies may be approaching the ‘tipping point’ of melting, contains a quantity of icy water capable of raising the level of the Earth’s oceans by up to six meters.SEE ALSO – Climate: the Arctic reached a record temperature of 38° in June 2020