An alarming crack-up has begun at the foot of Antarctica’s vulnerable Thwaites Glacier, whose meltwater is already responsible for about 4% of global sea level rise. An ice sheet the size of Florida, Thwaites Glacier ends its slide into the ocean as a floating ledge of ice 45 kilometers wide. However, now this ice shelf, riven by newly detected fissures on its surface and underside, is likely to break apart in the next 5 years or so.
A collapse of the entire glacier, which some researchers think is only centuries away, would raise global sea level by 65 centimetres, and because Thwaites occupies a deep basin into which neighboring glaciers would flow, its demise could eventually lead to the loss of the entire West Antarctic Ice Sheet, which locks up 3.3 metres of global sea level rise. “That would be a global change,” says Robert DeConto, a glaciologist at the University of Massachusetts, Amherst. “Our coastlines will look different from space.”
[More at the link below.]