If Thwaites falls into the sea, it could set in motion a collapse of the ice sheet and the disintegration into the sea of more glaciers now being held back by it, and they could jointly raise sea level by 4 ft. (1.2 meters) over the next two centuries by one conservative estimate. You see other scientists worrying that it could be a 10 ft. rise. Thwaites alone would raise sea level by 2 feet (0.6 meters). The conservative IPCC report of the United Nations in 2018 was only expecting a 1 to 3.6 feet rise in sea level this century, and was not counting on a Thwaites collapse.
https://www.juancole.com/2020/02/antarctica-thwaites-glacier.html
