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/ Source: Associated Press
By Associated Press
] WASHINGTON ̵
The Jakobshavn Glacier (YA-cob-shawv-en) around the year 2012 retreated 1.8 kilometers (3 kilometers) and thinned annually by nearly 40 meters. According to a Monday study from Nature Geoscience, it has grown at about the same rate over the last two years. Study authors and external scientists consider this to be temporary.
"That was a surprise. We got used to a runaway system somehow, "said Jason Box, Geological Survey of Denmark and Greenland. "The good news is that it reminds you that it's not necessarily that fast. But it goes on.
Box, who did not participate in the study, said Jakobshavn was "probably the Greenlandic glacier because it removes most of the ice in the northern hemisphere. It's king for all of Greenland. "
A natural cyclical cooling of the waters of the North Atlantic likely led the glacier to reverse the course, said study lead author Ala Khazendar, a NASA glaciologist for the Oceans Melting Greenland (OMG) project. Khazendar and his colleagues say that this coincides with one stroke of the North Atlantic Oscillation – a natural and temporary cooling and warming of parts of the ocean that is like a distant relative of El Nino in the Pacific.
The water in the Disko Bay, where Jakobshavn meets the sea, is 3.6 degrees cooler (2 degrees Celsius) than a few years ago, according to the authors of the study.
While these are "good news" at times, this is bad news in the long run. He tells scientists that sea temperature plays a greater role in glacier recessions and advances than previously thought, NASA climate scientist Josh Willis said , a co-author of the study. Over the decades, warming and warming due to human-induced climate change, he said, found that about 90 percent of the heat captured by greenhouse gases was released into the oceans.
"In the long run, we'll probably do that." We need to raise our sea-level rise forecasts yet again, "said Willis.
Think of the sea temperatures near Greenland as an escalator slowly rising from global warming, Khazendar said. However, the natural North Atlantic Oscillation is sometimes like jumping down a few steps or jumping up a few steps. The water can become cooler and have an impact, but in the long run it will become warmer and the melting will be worse.
Four external scientists said the study and results made sense.
Ian Joughin, who was not part of the study and predicted such a change seven years ago, said it was a "grave mistake" to interpret the latest data as contradictory to the science of climate change.
What happens is Joughin said "Largely a temporary blip. Although the equity market is on the decline, the overall long-term price has risen. That's really the same thing.
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