“Thwaites is the widest glacier in the world,” says Ted Scambos, US lead coordinator for ITGC. “It’s doubled its outflow speed within the last 30 years, and the glacier in its entirety holds enough water to raise sea level by over 2 ft (0.6 m). And it could lead to even more sea-level rise, up to 10 ft (3 m), if it draws the surrounding glaciers with it.”