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Leeds (dpa) - According to scientific studies, the earth has lost trillions of tons of ice in recent years.

From 1994 to 2017, 28 trillion tons of ice melted.

This corresponds to a 100-meter-thick block of ice the size of Great Britain, the researchers emphasize after a global inventory.

While in the 1990s an average of 0.8 trillion tons of ice disappeared each year, it was already 1.2 trillion tons in 2017.

For the study, which was published in the journal “The Cryosphere”, according to the authors, global satellite data were evaluated for the first time and partially supplemented by earth-based studies - not only on the polar regions, but also on the 215,000 mountain glaciers.

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"Although every region that we have examined has lost ice, the losses of the ice sheets in Antarctica and Greenland have accelerated the most," the European space agency Esa quoted the lead author Thomas Slater as saying.

The two triggers of the ice melt are therefore the warmer atmosphere, the temperature of which has increased by an average of 0.26 degrees Celsius per decade since 1980, and the warmer oceans with an increase of 0.12 degrees per decade.

A good two-thirds (68 percent) of the ice that has disappeared can be attributed to the atmosphere - this applies above all to the Arctic sea ice and mountain glaciers.

32 percent of the ice melt occurs through the oceans - this particularly affects the Antarctic.

58 percent of the ice that has disappeared is in the northern hemisphere and 42 percent in the southern hemisphere.

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During the study period, the Arctic sea ice lost 7.6 trillion tons and the Antarctic Ice Shelf 6.5 trillion tons.

Mountain glaciers lost 6.1 trillion tons worldwide, the Greenland Ice Sheet 3.8 trillion tons and the Antarctic Ice Sheet 2.5 trillion tons.

The rest is mainly due to the Southern Arctic Ocean.

The loss of the terrestrial ice masses corresponds to a rise in sea level of almost 35 millimeters.

Melting sea ice does not cause the oceans to rise, but it does reduce the albedo - i.e. the reflection of sunlight - and thus intensify global warming.

"As the sea ice shrinks, more solar energy is absorbed by the oceans and the atmosphere," says co-author Isobel Lawrence.

"This ensures that the Arctic is warming faster than any other region on the planet."

Mountain glaciers contain only one percent of the world's ice volume, but they make up almost a quarter of the melted ice.

"Mountain glaciers not only contribute to the global rise in sea levels, they are also a crucial source of water for the people in the region," says co-author Inès Otosaka.

"The global retreat of glaciers is therefore of crucial importance at both global and local levels."

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© dpa-infocom, dpa: 210125-99-164015 / 3

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Communication Esa