Antarctica is covered by two huge masses of ice: the East and West Antarctic Ice Sheets, which feed many individual glaciers.
Due to global warming, the WAIS has been thinning at an accelerating rate over the past few decades.
Within the ice sheet, the Thwaites and Pine Island glaciers are particularly vulnerable to global warming and are already contributing to sea level rise.
Thwaites Glacier is nicknamed “Doomsday” for its rapid rate of melting.
Now a new study by the University of Maine and the British Antarctic Survey, including academics from Imperial College London, has measured the rate of local sea level change – an indirect way of measuring the loss of ice – around these particularly vulnerable glaciers.
They discovered that the glaciers have started to retreat at a rate not seen in the past 5,500 years.
With areas of 192,000 square kilometers (almost the size of the island of Great Britain) and 162,300 square kilometers respectively, the Thwaites and Pine Island glaciers have the potential to cause large rises in global sea level.
At the current rate of retreat, the study authors say, the glaciers could fuel a rise of 3.4m over the next few centuries.
What sea level rise will look like around the world
“Although these vulnerable glaciers have been relatively stable over the past millennia, their current rate of retreat is accelerating and is already raising global sea levels,” said co-author Dr Dylan Rood.
“These currently high rates of ice melt may signal that these vital arteries in the heart of the WAIS have ruptured, leading to an acceleration of ocean flow that is potentially disastrous for future global sea levels in a warming world. We now urgently need to determine if it is too late to stop the bleeding.”