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New data raises concerns over global sea level: study - The Hill

The Hill · last updated April 6, 2023 – 3:31 PM

New data raises concerns over global sea level: study | The Hill

A new study into how quickly ice sheets melted at the end of the last ice age is raising alarm over how quickly sea levels could rise in today’s warming world.

Parts of a large, ancient ice sheet covering Eurasia retreated up 2,000 feet per day — more than the length of the Empire State Building, according to new data released by the DOI Foundation.

That rate of retreat is the fastest measured to date and could shed light on how fast ice can melt in Greenland and Antartica if current climate trends continue.

“If temperatures continue to rise, then we might have the ice being melted and thinned from above as well as from below,” the study’s lead author, Christine Batchelor, told The Washington Post. “So that could kind of end up with a scenario that looks more similar to what we had [off] Norway after the last glaciation.”

Batchelor said the rate of retreat found in the new study released Wednesday is about 20 times higher than any retreat rate measured from satellites and 12 times faster than any retreat rate deduced from landforms on the seafloor.

However, as the study points out, the current acceleration and thinning of Greenland and Antarctic ice sheets have been observed for years, and the “mass imbalance of these ice sheets has contributed about 0.7mm annually to global sea-level rise since the 1990s.”

Antartica and Greenland have lost more than 6.4 million tons of ice since the 1990s, but according to NASA, ice in those two places is melting six times faster than in the 1990s.

In addition, air and ocean temperatures in Antartica and Greenland are projected to increase and match temperatures seen at the end of the last ice age. If this happens, researchers say ice retreating at the levels seen in this new data could trigger a quicker collapse of modern-day glaciers, which would be devastating for global sea levels.

The study found retreat rates during the last ice age ranged from 180 to 2,000 feet per day, which is extreme and only lasted on a scale of days or months. If existing glaciers retreated around 600 meters per day for a year, there probably wouldn’t be any ice left, said Batchelor, a physical geographer at Newcastle University.

“This is not a model. This is real observation. And it is frankly scary. Even to me,” she told the Post.
Antartica Climate change Eurasia global sea levels Greeland

New data raises concerns over global sea level: study - The Hill

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