Monday , March 1 2021

NASA study on the Antarctic glacier "makes several disturbing discoveries"



In NASA's words, "several disturbing discoveries" were raised by his research on the colossal Thwaites glacier in Western Antarctica. At the top of the usual ice story, they found a gigantic cavity – perhaps the size of the Eiffel Tower – growing at the bottom of the vast glacier.

The Thwaites glacier, about the size of Florida, already contained more than 14 billion tonnes of frozen water, enough to raise sea level in the world by more than 2 feet (65 centimeters). However, large quantities of this giant ice cube have dissipated in the last three years as a result of climate change, contributing to about 4% of global sea level rise.

As reported in the journal Advances in science, the researchers gained a clearer picture of the glacier's situation. Their findings show that the Thwaites Glacier is suffering from extensive thinning of ice, backtracking and childbirth, as well as a 300-foot hole within its west wing that is growing at an "explosive" rate.

"[The size of] a cavity under a glacier plays an important role in melting, "said study leader Pietro Milillo of NASA's Jet Propulsion Lab (JPL). declaration. "The more heat and water under the glacier, it melts faster."

The cavity can be seen in the center of the GIF in dark red. NASA / JPL-Caltech

A NASA-led team studied the glacier using satellites and specialized aircraft armed with ice-penetrating radar to provide researchers with high-resolution data on the ever-changing shape and size of the glacier. These data also shed some light on another concern with the glacier's ground line, the point at which the glacier begins to move away from the earth and float into the sea. Research has shown that the Thwaites Glacier is peeling off the bedrock below it, which means that more of the glacier base is exposed to warm waters. In turn, this makes the glacier even more susceptible to melting.

"We suspected for years that the Thwaites were not tightly bound to the bedrock below," said Eric Rignot of the University of California at Irvine and NASA's JPL. "Thanks to a new generation of satellites, we can finally see the details."

The Thwaites glacier plays a key role in the history of sea level rise and climate change, so there has never been a greater effort to study and understand it. Just this week, an icebreaker left Chile to begin a scientific expedition to Thwaites Glacier with the help of several other ships, researchers, airplanes and wild seals.

"Understanding the details of how the ocean melts this glacier is essential to projecting its impact on sea-level rise in the coming decades," added Rignot.


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