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Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Science https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ In Greenland and Antarctica even "safe" ice melts quickly – quartz


It was a bad ice week. Last Tuesday, the researchers announced that the East Antarctic ice shelf, which was previously thought to be stable or even growing, is actually melting alarmingly fast. And yesterday (January 21st), a new study found that southwestern Greenland, another area where ice was supposed to be safe, discards more melting waters in the ocean than any other area on the ice island.

"We will see a faster and faster rise in sea level in the foreseeable future," said Michael Bevis, lead author of the Greenland study. "Once you hit this critical point, the only question is: how severe is it?"

Greenland has long been a major source of concern for scientists studying sea level rise. But they thought their worst worries were the southeastern and northwest regions, where massive glaciers lived, crashing into the icebergs when it became too warm. The bergs are carried in the sea and melted by adding water to the oceans. Southwest Greenland, on the other hand, does not have many glaciers, so it does not cause many icebergs. But Bevis's team found that during the hotter summers the rising rivers of molten waters poured from the southwest directly into the sea, accelerating the loss of ice. By 2012, Greenland melted four times faster than in 2003, according to the study, led by the loss of ice in the allegedly southwest.

Ninety-seven percent of the surface of Greenland's glacier layer melted in 2012. Ice melting on the island has not been seen since 1889, according to Kateyn Keagan, Dartmouth's research fellow who studies the Arctic ice. In a typical year, she says, summer temperatures reach a maximum of -14 ° C. But she remembers the surreal feeling of working in the middle of Greenland's ice sheet in the summer of 2012 when the temperatures climbed above freezing. "When the wind was still, you can go out in a T-shirt," she says.

It is unclear exactly how much melting water from unexpected areas like southwest Greenland has to change our forecast for sea level rise. But the researchers are not optimistic. "Raising sea levels is an area of ​​climate change research, where there are many unknowns," says King. "But if you take an ice table from Greenland and put it directly into the sea at a faster pace than any other model, it would mean that sea level forecasts are perhaps a little conservative."

"This is just another indication that these changes are not a forecast for the future or the things that have to worry about 20 years," says Eric Klein, a geology professor in Alaska who was not involved in the study. These changes are not far-off, not in terms of time or space: If we lose an ice from Greenland or Antarctica and the seas rise, it will be felt globally, not only in the Arctic or Antarctic. "

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