The Arctic is the area around the North Pole, at the top of the Earth. Most of the Arctic is ocean. The Arctic Ocean is bordered by Greenland, Canada, Norway, Alaska and Russia. Sea ice is frozen seawater that floats on the ocean. On land, the ground can be permafrost. Permafrost is ground that stays frozen for at least two years. On about June 21 the Arctic has 24 hours of sunshine.

Antarctica is a continent, and a huge sheet of ice covers it. The Antarctic Ice Sheet is the largest single mass of ice on Earth. As of November 2026, it covers almost 14 million square kilometers. That is about the area of the lower 48 states and Mexico together. A glacier is a slow-moving river of ice. Icebergs are large chunks of ice that break off glaciers. Antarctica's sea ice grows in winter, when the ocean around the continent freezes.

As of November 2026, Antarctica is extremely cold and dry. Much of it is a desert. Very little snow falls in the middle of the continent. Antarctica has no native people. Scientists and other people live and work at research stations there. The Antarctic Treaty sets Antarctica aside for peaceful science.

Polar bears live in the Arctic and eat seals. They hunt by waiting at seal breathing holes in the ice. Polar bears are strong swimmers, and they paddle with their large front paws. A mother polar bear digs a den in the snow. She has her cubs there in winter, usually twins.

Other Arctic animals live in the water. Narwhals live in the Arctic Ocean. A male narwhal's tusk is a tooth that grows out through the front of its jaw. Belugas are white whales that make many sounds. Seals keep warm in cold water with a thick layer of fat called blubber.

Emperor penguins are birds that cannot fly, and they live in Antarctica. They are the largest penguins. They huddle together to keep warm. Antarctic krill are small, shrimp-like animals that most of the larger animals in the region eat. Polar bears do not live in Antarctica. Penguins do not live in the Arctic.

Words to know

• permafrost: frozen ground
• blubber: thick body fat
• krill: tiny sea animals
• treaty: signed agreement