In December, researchers reported that huge and growing cracks have formed in the eastern ice shelf of the Thwaites Glacier, a Florida-size mass of ice that stretches 75 miles across western Antarctica.
They warned that the floating tongue of the glacier—which acts as a brace to prop up the Thwaites—could snap off into the ocean in as little as five years. That could trigger a chain reaction as more and more towering cliffs of ice are exposed and then fracture and collapse.
