The Polar Regions: Arctic and Antarctic

The Arctic is the region around the North Pole. It is mostly a frozen ocean — the Arctic Ocean — covered by a floating sheet of sea ice. The Antarctic is the region around the South Pole. Unlike the Arctic, Antarctica is an actual continent: a vast landmass buried under an ice sheet up to 4.8 kilometres thick. This is one of the most important differences in all of geography: the north is frozen sea, the south is frozen land.

The poles have the most extreme daylight on Earth. Because the planet is tilted, in the polar summer the Sun never fully sets, giving weeks of constant daylight known as the midnight Sun. In the polar winter the opposite happens: the Sun never rises, plunging the region into months of darkness. This single tilt of the Earth is what creates these astonishing long days and long nights.

Despite extreme cold, both polar regions teem with life. Polar bears, Arctic foxes, and walruses live in the Arctic. In Antarctica, penguins huddle against bitter winds, and the surrounding Southern Ocean is rich with krill that feed whales, seals, and seabirds. Animals here survive thanks to special adaptations: thick fur, layers of fat called blubber, and white coats that hide them against the snow.

People live very differently in the two polar regions. The Arctic has been home to indigenous peoples, such as the Inuit, for thousands of years, who learned to hunt, fish, and build shelters in the cold. Antarctica, however, has no permanent residents at all — only scientists who visit research stations to study the ice, the wildlife, and the climate, often staying for just a season at a time.

The polar regions play a huge role in regulating Earth's climate. The white ice and snow reflect sunlight back into space, keeping the planet cooler. As ice melts due to climate change, dark ocean and land are exposed, which soak up more heat, so less sunlight is reflected and the warming speeds up. This worrying loop is called the ice-albedo feedback, where warming causes melting and melting causes still more warming.