A key Antarctic ice shelf is in perilous danger of “shatter[ing] like a car windscreen” and thus accelerating the flow of the massive Thwaites Glacier into the Southern Ocean, scientists warned Monday. U.S. and U.K. researchers presenting at the American Geophysical Union warned warming waters are thinning and weakening the ice shelf, the collapse of which would allow the glacier, which is the size of Florida, to triple its speed into the sea.

In a “doomsday” scenario, the complete melting of the Thwaites Glacier alone would raise global sea levels by more than two feet (65cm). Warmer temperatures are also melting the glacier from below, unmooring it from bedrock and accelerating its flow into the sea.

“There’s going to be a dramatic change to the front of the glacier within less than a decade,” Ted Scambos, a senior research scientist at the Cooperative Institute for Research in Environmental Science, told reporters. “When that happens, the fast-flow part of Thwaites is likely to widen because bracing on [the] east side may be gone. It may still take a few decades before some of the other processes … [but] it will effectively widen the dangerous part of the glacier.” (Gizmodo, Washington Post $, BBC; Interactive feature on Antarctic climate impacts: New York Times $; Climate Signals background: Glacier and ice sheet melt)