Ice Sheets

glaciers · frozen earth · polar regions · climate

Massive frozen blankets. Ice sheets are huge areas of ice covering more than 50,000 square kilometers, which is about the size of a large country. They're the biggest glaciers on our planet and can be incredibly thick, sometimes stretching over a mile deep.

Only two exist now. Today, the only ice sheets on Earth are in Antarctica and Greenland. Thousands of years ago, there were more ice sheets covering parts of North America and Europe, but they melted away as Earth warmed up.

Ice flows outward. Ice sheets have high points called ice domes where ice starts pushing outward in all directions, like ripples spreading from a stone dropped in water. The ice flows toward the edges through special rivers of ice called ice streams.

Different from glaciers. Ice sheets are much bigger and flatter than mountain glaciers or ice caps, which are smaller patches of ice on high peaks. An ice sheet is so massive it covers entire continents and shapes the landscape underneath it.

Holds fresh water. The Antarctic ice sheet alone contains about 26.5 million cubic kilometers of ice, and if it melted completely, it would raise ocean levels around the world. This frozen water is one of Earth's biggest freshwater storage areas.