TO CLOSE

A cavity two-thirds the size of Manhattan has formed under one of the most dangerous glaciers in the world. Sam Berman of Veuer has complete history.
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The Thwaites Glacier is one of the most dangerous glaciers in the world and scientists are eager to travel to Antarctica to study it.

NASA researchers published a study in January that said a giant cavity, about two-thirds the size of Manhattan, was melting quickly under the glacier due to climate change. The cavity is large enough to contain 14 billion tonnes of ice, most of which has melted in the last three years.

Even before this cave, Thwaites' rapid loss of ice and its potential impact on the global sea level were significant enough for researchers around the world to consider physically doing so from this year.

According to the Natural Environmental Research Council, NERC, only 28 people have already set foot on the glacier.

So what could happen if Thwaites collapses?

"This could potentially destabilize the entire West Antarctic region," said TODAY USA's Lucas Zoet, a geoscientist at the University of Wisconsin.

Thwaites is a "wildcard" for sea levels

The glacier is located in the West of Antarctica and flows into the sea of ​​Amundsen. The Thwaites melt, about the size of Florida, is currently responsible for about 4% of the sea level rise in the world, according to NASA in its recent study on the hole giant of the glacier.

More: Melting ice from Greenland and Antarctica could cause extreme weather conditions

"This is an important way to see how the ice is discharging into the ocean since western Antarctica," Zoet said.

Thwaites has been hard to study because it is far from the American bases in Antarctica and also because the weather is "particularly bad," said Zoet.

The glacier is more than 70,000 km 2, making it one of the largest glaciers in the world, NERC said.

A map of where Thwaites is located. (Photo11: USA TODAY & # 39; HUI)

The bottom line of the glacier, the point where ice meets the land below, has declined more than 9 miles between 1992 and 2011, according to NERC. As ice and warmer seawater sink beneath the glacier, they detach from the earth and accelerate its retreat.

"If this cavity gets bigger or bigger, that's one of the ways out of this last ridge that Thwaites Glacier hangs on," Zoet told USA TODAY.

What worries scientists in particular is that melting is accelerating. According to the NASA study, if all Thwaites ice was lost, the ocean level would increase by two feet. But the glacier also supports nearby glaciers. If glaciers also melt, sea level could rise by an additional eight feet, warn researchers.

More: Here are the facts: Despite winter storms, global warming is real

"It's kind of a joker to be able to raise the sea level rise rate fairly quickly if the situation changes in a certain way," said Ted Scambos, senior research scientist at the National Data Center. snow and ice.

How do you visit a place so far away?

Scambos said that Thwaites' retreat research had begun as early as the 1990s, when satellite data made it possible to better track the Antarctic ice sheets.

Scambos is part of the International Thwaites Glacier Collaboration (ITGC), a partnership between British and American scientists that is closely studying the retreat of the glacier.

"Satellites show that the Thwaites area is evolving rapidly, but to answer the key question of how fast and how fast sea levels will change in the future, scientists in the field with Sophisticated equipment to collect the data needed to measure ice volume, or ice mass change, "said William E. Easterling, deputy director of the Geosciences Branch of the National Science Foundation, in a statement.

More: According to a study, melting glaciers in the Arctic reveals hidden land for 40,000 years

Saying projections

"The problem is not so much whether this will happen or not, unless we really change the amount of gas trapped by the heat we emit into the atmosphere," said Scambos about melting glacier. "In the end, we will lose large areas of Antarctica, large areas of Greenland." The important thing is to know how fast this will happen.

According to a study published in February in Nature, the melting of Greenland and Antarctica would not only raise sea levels, but could also result in extreme weather conditions and dramatic temperature changes.

Scambos said coastal cities in the United States and around the world were studying the potential consequences of sea level rise. If Thwaites were to be based on centuries, nations would have more time to prepare.

However, a faster rise in sea level could force countries to act more urgently.

If this rate doubled or tripled suddenly because the melting of glaciers was accelerating, "this will really undermine the ability of these countries to plan and prepare for the impacts of rising sea levels," said Scambos.

More: Antarctic ice melts 6 times faster than in the 80s

More: The collapse of the Antarctic Ice Sheet could recur and trigger a new global flood

Follow Brett Molina on Twitter: @ brettmolina23.

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