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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/ Greenland's most critical glacier suddenly wins ice, but it may not be a good thing

Greenland's most critical glacier suddenly wins ice, but it may not be a good thing



Although this finding is a surprising and temporarily good news for the glacier, limiting its contribution to raising sea levels, the cause of ice accumulation can lead to a long-term crash.

For two decades, Jakobshavn maintained a remarkably consistent thinning. that scientists believe they will continue if not accelerate due to the widespread warming of the polar atmosphere and the oceans – but that speed was drastically slowed down in 2014, and the glacier actually grew between 2016 and 2017 and again between 2017 and 2018, according to a study published on Monday in Nature magazine.

"We did not believe at first," said Ala Hazander, NASA's leading research scientist. "We have assumed that Jakobshavn will continue to work as he has been in the last 20 years.

Jakobshavn Isbrae, the full name of the West Greenhouse Glacier, is Greenland's fastest-running and largest glacier glacier over the last 20 years, making it the biggest contributor to rising sea levels.

In fact, according to Hazander, the melting of this single glacier only contributes to the global oceans, which rise by an average of 1

millimeter between 2000 and 2010.

And although Jakobshavn has earned ice at the lowest levels where it enters the sea still contributes to rising sea levels because the melting speed in the ocean is still higher than the ice accumulation rate higher than the glacier, according to the researchers.

controls the pool with enough ice that if it melts completely it will raise the global oceans by about 2 feet.

CNN Interactive: Global Warning

This threat and the rapid speed Jakobshavn has been Over the next few decades the ice has caused the glacier to enter the icy coast and make the glacier one of, if not the most studied glaciers in world.

Khazendar, along with a team of other NASA scientists, used a number of NASA data sets to analyze Greenland's ice, oceans and atmosphere, including those from the latest targeted research missions called the Oceans melting Greenland, and the Ice Bridge operation to determine the likely cause of Jakobshavn's recent face.

The cooling water cooled the progress of Jakobshavn

Scientists attributed the acquisition of ice to the local cooling of the ocean.

Between 2014 and 2016, waters up to 2 degrees Celsius (3.6 degrees Fahrenheit) entered the Disco Bay, where the Icehock Jakobshavn entered the water.

Researchers believe that cooling is associated with natural climate change in the Northern Hemisphere, known as North Atlantic oscillation, which may warm or cool the northern parts of the Atlantic Ocean over several years (not too different from the impact El Nino and La Nina may have on the Pacific Ocean temperatures).

  Through the detailed observations, Khazendar and the team managed to trace this cooler water from the open northern Atlantic Ocean to the bay </p>
<div class=
  Glacier view

Disco and found that the time coincided with the transition of the glacier to the ideal acquisition of ice.

"Over the last two to three years, the role of the ocean has been dominant," Hazander said.

But at the end of the 1990s, much warmer water entered the bay, melting the ice shelf that protected Jakobshavn. a glacier that sets off the incomparable melting that characterizes the glacier for the next two decades.

"It's like an experiment that's been doing 20 years," Hazender said.

He said the dramatic response to the glacier of ocean temperature changes forced scientists to reassess how sensitive the glaciers were to slight changes in the ocean's climate.

The cooling of the North Atlantic is a flash of the radar, a localized effect that will eventually warm up when the North Atlantic oscillation goes back. This will happen at the same time as climate change will raise the temperature of the oceans.

"This is an extension," said Hazlander of the recent thickening of the Jacobshaw glacier, "not a resurrection."

"The answer to a glacier does not mean that things have changed," said Marco Tedesco, a researcher at the Earth Observatory of the United States of America, the scientist warns not to read too much about the news of one of the most critical glaciers in the world. Lamon-Doherty of Columbia University.

"Greenland at present [losing]) is about 270 gigatonnes (a billionth of a million tonnes) of ice annually … mass loss has accelerated over the last decades, with Greenland being the biggest contributor to sea-level rise," Tedesco, does not participate in the New Study, writes in an email.

Erik Rinot, a university scientist at the University of California, Irvine and JPL's senior researcher, noted that "the chances that this will continue is very low, in my opinion." It was only a matter of time before, that the glacier began to regress again – perhaps this summer, perhaps next year. "

  Global Warning: Arctic Melt
However, the presidential tweets on climate change on several cold days do not deny the overall warming trend of the whole planet . "We must not confuse the climate with local variability," said Rigoth, who was not involved in the study. "The latter is what we see here."

The results show that glaciers are extremely vulnerable to both hot and cold temperatures, and this is not good news for the future.

Most of the warmth of global warming comes straight into the oceans – studies show more than 90% – and this leads to global warming levels in the ocean that are rising every year.

"The next time the warm waters return to Jakobshavn, they will be even


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