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NASA warns that a dangerous iceberg in Antarctica is about to collapse




The Thwaites Glacier, in Antarctica, is currently responsible for about 4 percent of sea level rise worldwide Source: Archive

A huge 40-square-mile cavity and a 300-meter high cave grows at the bottom of the Thwaites glacier in western Antarctica, confirming that this ice mass is falling apart.

This is confirmed by a new study under leadership

NASA,

It also stresses the need for detailed observations of the lower part of the Antarctic glaciers in order to calculate how rapidly global sea levels will increase in response to climate change.

Scientists hoped to find some gaps between ice and rocks at the Thwaites base where ocean water could flow and melt the glacier from below.

However, the size and speed of the new hole exploded. It is large enough to hold 14 billion tons of ice, and most of this ice melt in the last three years.

"For years, we have suspected that Thwaites was not well connected to the underlying rock," said Eric Rignot of the University of California, Irvine, and NASA's Jet Propulsion Laboratory (NPL). Rignot is co-author of a new study, which
is published in scientific cash registers. "Thanks to the new generation of satellites, we can finally see the details," he said.

The cavity was unveiled with radar for ice penetration in Operation NASA Operation IceBridge, an air campaign that began in 2010 and studies connections between the polar regions and the global climate.

Researchers also used data from constellations of synthetic radar from the Italian and German spacecrafts. These high-resolution data can be processed by a technique called radar interferometry, which reveals how the surface of the earth moves below.

"[El tamaño de] The cavity under the glacier plays an important role in melting, "said lead author Pietro Milillo of the JPL." When more ice can penetrate heat and water, it melts faster, "he said.

Numerous models of ice tables use a solid form that represents the cavity under the ice instead of allowing the cavity to change and grow. The new discovery assumes that this restriction is likely to cause these models to underestimate how quickly Thwaites loses ice.

The Thwaites Glacier, the size of the state of Florida, USA, is currently responsible for about 4 percent of sea level rise worldwide. It has enough ice to lift the ocean just over 2 centimeters and maintains adjacent glaciers that would raise the sea level by 2.4 centimeters if the whole ice was lost.

Thwaites is one of the most difficult places to reach Earth, but will be better known than ever. The National Science Foundation of the United States and the National Environmental Research Council of the United Kingdom are preparing a five-year field project to answer the most critical questions about their processes and properties. International Thwaites Glacier Collaboration will begin its field experiments on the southern hemisphere in the summer of 2019-20.

The giant cavity lies beneath the main glacier trunk on its western side, the most remote side of the western Antarctic peninsula. In this area, when the tide rises and falls, the earth clutch retracts and progresses over an area of ​​approximately 3 to 5 kilometers.

Since 1992, the glacier has been separated from the ridge in the bedrock since the end of 1992 at a constant speed of approximately 0.6 to 0.8 kilometers. In spite of this steady rate of retreat, the degree of fusion on this side of the glacier is extremely high.

The DPA agency


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