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NASA scientists track Greenland melting ice and results not good



BEFORE NASA'S GREENLAND RESEARCH PLAN – Pulsed ice fields 500 feet below NASA plane give way to blue-green water strewn with irregular pieces of bleached white ice, some as tall as bitcoin, some as tall as 15, some -storey buildings.

Like almost any other Greenland glacier, the massive Kangerlussuaq is melting. In fact, the giant Frozen Island has seen one of its biggest melt-ins to record this year. NASA scientist Josh Willis is scrutinizing the phenomenon, hoping to figure out exactly how global warming eats Greenland's ice.

In particular, he wants to know whether melting is caused by more than warm air or warm seawater. The answer can be decisive for the future of Earth.

Read: Trump may want to buy Greenland, and the Internet says "wait, what?"

Water carries more heat for something frozen as fast as air than anyone who once thawed the steak under the tap. knows.

If Willis's theory that much of the damage was from water turned out to be correct, he said, "There is much greater potential for Greenland to melt faster than we thought." And that means the seas they rise faster and coastal communities flood more.

Greenland contains enough ice to allow sea levels to rise by 20 feet if they all melt. In just one day this month, it lost a record 1

3.7 billion tonnes, according to one estimate.

"It's a little scary," Willis said, looking down at an area filled with more water than ice. "We are definitely watching the ice sheet disappear in front of us."

Climate change is eating into the Greenland glaciers in two ways. The most obvious way is from the warm air above, which was brutal this summer, with the European heatwave working in July as an ice dryer. The other way is from warm, salt water, part of it from the Gulf Stream in North America, crashing along the coastal glaciers below.

When University of Georgia ice scientist Tom Mott, who was not part of this project, began exploring Greenland glaciers in the early 1990s, researchers really didn't think water was a big factor.

The Willis project – called Oceans Melting Greenland, or OMG – shows this to be the case. Now the question is how much and how fast.

What Willis measures is water 660 feet or more in length below the surface that is warmer and saltier than the things that touch the air. It is this deep water that causes the greatest damage.

To measure this, NASA spent five years crossing the island in a deceptively 77-year-old DC-3 built for World War II. Willis, project manager Ian McCubbin and mechanic Rich Gill drop long cylindrical probes through a special tube in the floor of the aircraft, watching the sensors drop by parachute and then dive into the cold water.

McCubbin then waits for a tone on his computer that tells him that the probe is underwater and measures temperature and salinity. When all five flight probes start signaling – with a sound that McCubin resembles a "fax machine or AOL modem" – he and Willis are high five.

Meanwhile, pilots Andy Ferguson and Don Waters are stowing the plane to the blue-green spots, searching for the next destination and pointing out the stunning giant icebergs and signs of glacial retreat on the radio.

As the data is transmitted back from a $ 2000 probe now deep into the water near Kangerlussuaq in eastern Greenland, initially it seems that temperature has not changed much in the last year or two, which may be good news . But this is just one data point. Every year for the past four years, NASA has been exploring all over Greenland, and overall the numbers are not so calming.

If water plays a much larger role than scientists thought, it could mean that the seas will rise faster and higher than expected. That's because 90% of the heat from climate change goes to the oceans, Willis said. Hot water provides a "bigger bang for the buck" than air when it comes to melting ice, Willis said.

Just how decisive is the melting of seawater was illustrated, somewhat paradoxically, by the Jakobshavn glacier, the fast-growing Greenland glacier is the more populated western coast. In recent years, it has suddenly started to increase slightly, possibly due to water cooling as a result of temporary changes in weather and patterns of water currents, Willis said.

In general, the oceans warm much more slowly than the air, but remain warmer. Water weakens glaciers and causes icebergs to break. These icebergs eventually melt away, adding to the seas.

"Some are as big as a city," Willis says.

A 2019 study by Danish climatologist Ruth Motram examined 28 glaciers in Greenland in the long term. data. Almost all are melting away, with only one or two that could be considered as stable.

"A retreating glacier seems inattentive, but 28 retreats are a sign of something happening," Mottram tells the Associated Press.

A 2017 study concluded that coastal glaciers and ice caps – what Willis was studying – reached a "tipping point" for the loss of ice in 1997 and have since deteriorated rapidly. A NASA satellite found that Greenland's ice sheet was losing about 255 billion metric tons annually between 2003 and 2016, with the overall loss rate worsening.

It will take centuries for all of Greenland's massive ice cover to melt away, but how fast is the key question. If warm water plays a greater role than scientists suspect, by 2100 Greenland alone could cause a sea level rise of 3 or 4 feet (more than 1 meter), Willis said.

Other scientists, such as University of Colorado Ted Scambos, say that Greenland's contribution to sea level rise by 2100 is likely to be closer to 1 foot (30 centimeters).

This is a big spread.

"I am in favor of a larger number, but I hope a smaller number," says Maryland County Glaciologist Christopher Schumann, whose family owns properties along the coast.


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