Home South pole ice More rain than snow in the Arctic – in 30 to 60 years

More rain than snow in the Arctic – in 30 to 60 years

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More rain than snow in the Arctic – in 30 to 60 years


The rain is coming earlier than expected. In 30 to 60 years, it will rain more than snow in the North Polar region. This is decades earlier than expected. Even if global warming remains below the 1.5 degree limit, this trend is unlikely to change. The previous scenarios assumed that the rain would push back the summer and fall snowfall only later, namely between 2070 and 2090.

Researchers in Canada have come to this disturbing conclusion from the University of Manitoba and the National Snow and Ice Data Center in the United States. They talk about it in the journal “Nature Communications”.

That the pattern of precipitation in polar regions would change with increasing global warming was already evident in the 2019 IPCC Intergovernmental Panel on Climate Change Special Report on the Ocean and Cryosphere. However, scientists have adapted the newly developed precipitation models. more precisely to the physical conditions of the north polar region. In doing so, they clarified the effects of the IPCC scenarios. The result: more precipitation will soon fall over the Arctic, which is almost exclusively due to increased precipitation in summer and fall. In winter it remains with snow.

It will first hit the Arctic Ocean, Siberia and the northern Canadian island world. In the Atlantic sector of the North Polar region, that is to say in Greenland and the Barents Sea on both sides of the Svalbard archipelago, the evolution is already being measured today. Only a decade or two later, it will rain more on the Pacific side of the Arctic, that is, in Alaska, eastern Siberia, the Beaufort and Chukchi seas. The consolation is that snowfall will dominate here for a long time to come, even if global warming approaches three degrees by the end of the century.


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As always with climatic phenomena, the reason is the complicated coupling of physical conditions. Ice loss, which has progressed for decades, exposes increasingly large areas of water in summer and fall, from which more moisture can rise. At the same time, the lower atmosphere gets hotter and hotter and thus stores more humidity. It rises, drifts towards the pole and rains towards the north. Thus, the water cycle changes radically and thus influences ecosystems and biodiversity, and ultimately also the living conditions of the four million people who live here and mostly belong to indigenous peoples.

Further south, the amount of rainfall is more dependent on the overall temperature trend. In western Russia and Europe, for example, there won’t be much more rainfall until global warming approaches the two-degree limit. In Greenland, however, this can occur at around 1.5 degrees of global warming.

It is true that it will continue to snow more on the central Greenland ice sheet, which could compensate for the loss of ice on the edges. But in the south and on the coasts, the rain replaces the snow. The tongues of glaciers protruding into the sea then become more rapidly unstable, break and melt. This loss of ice is then probably greater than the increase due to more snow inside.

More rain in arctic regions has profound consequences everywhere, warn the authors of the study. When the snow season shortens, the dark surface of the continent and the sea absorbs heat from the sun instead of reflecting it in snow and ice. The well-known consequence: Permafrost soils thaw and more climate-damaging methane escapes, which in turn further stimulates global warming.

For caribou, reindeer and muskox, it becomes dramatic when rain falls on the snow and forms a thin layer of ice. If the animals try to scrape mosses, lichens and fungi from under the snow with their hooves, they injure themselves so badly on the sharp-edged sheet of ice that they die. For the polar natives, a catastrophe which is already not uncommon today. Because it is especially the two species of deer, the caribou and the reindeer, which are their livelihood.

More water from above also causes the already huge rivers of Siberia and northern Canada to rise. Downstream, this leads to flooding which not only tears apart villages, paths, roads, power lines and pipelines, but also breaks up sea ice on the coast, which then melts more quickly.

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But the effects of more rain in the Arctic can still be felt far south in the Atlantic. After all, this means that even more fresh water is entering the sea than it already does through melting sea ice. It forms a layer over the salty and heavier water of the ocean and can disrupt the circulation of the North Atlantic and the foothills of the Gulf Stream.

In no other region of the world is climate change progressing as rapidly as in the Arctic. Since 1971, it has warmed three times faster than the rest of the earth, as documented by the Arctic Council’s monitoring program in a report. This council is an intergovernmental forum for all neighboring countries and indigenous peoples around the Arctic Ocean. He follows the evolution of the climate around the Arctic Ocean very closely and says in the report that the Arctic has warmed by more than three degrees since 1971, while the average temperature of the rest of the world has only increased. than about a degree. Heat records are also on the rise, as was the case this year, when temperatures in parts of northern Siberia reached over 30 degrees Celsius in May, while it was still uncomfortably cool in central Europe.

But there are also winners, as the Arctic Council’s project for the conservation of arctic flora and fauna shows: namely migratory birds who already dare to build their breeding grounds a little further north. And of course also economic speculators who hope for more convenient access to precious minerals or even more arable land on the still frozen ground.


(jle)

Disclaimer: This article is generated from the feed and not edited by our team.