A 618-square mile block of ice is about to drop off Antarctica

A new study says Antarctica's Larsen B Ice Shelf may completely disappear by 2020.

The 10,000-year-old shelf partially collapsed in 2002, and there is only a 618-square mile slab left.

“These are warning signs that the remnant is disintegrating,” Ala Khazendar, a researcher at the NASA-affiliated Jet Propulsion Laboratory (JPL) who co-authored the study, told Time.

“Although it’s fascinating scientifically to have a front-row seat to watch the ice shelf becoming unstable and breaking up, it’s bad news for our planet.”

It was previously thought that since the glaciers in the area that survived the 2002 collapse appeared relatively unchanged, they were sufficiently buttressed by the remnant of the shelf.

But Khazendar and his colleagues studied how quickly two of the shelf’s main glaciers were melting and found that the rate at which they were disappearing into the ocean has increased more than 50 per cent since 1997. Their findings predict that the entire shelf will vanish within the next five years.

If the shelf melts as quickly as predicted it will speed up the rise of sea levels around the world, since ice shelves slow the rate at which other ice enters the ocean.

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