When you picture the world’s fresh water, you might think of the Great Lakes, the Amazon River, the Mississippi. None of those compare to Antarctica. The frozen continent at the bottom of the world holds about 60% of all the fresh water on Earth - all of it locked up in a massive ice sheet that covers nearly the entire continent.
Antarctica’s ice sheet averages about 1.6 kilometers (1 mile) thick, but in places it goes more than 4 km deep. The whole continent is roughly 14 million square kilometers - bigger than the United States. Underneath the ice are mountains, valleys, and even subglacial lakes, but you’d never know it from the surface.
If Antarctica’s ice ever fully melted (which would take thousands of years), global sea levels would rise about 60 meters (around 200 feet). That would put most of the world’s coastal cities underwater - New York, London, Mumbai, Shanghai, Tokyo. Even partial melting matters: as warming continues, scientists are closely watching massive Antarctic glaciers like Thwaites (nicknamed the “Doomsday Glacier”) because their collapse could meaningfully raise sea levels worldwide.
