Antarctica

Snow falls on Antarctica year after year.

The snow gets squashed into ice. The ice slowly flows to the sea. Big pieces break off and float away as icebergs.

The ice sheet formed as snow and frost piled up and were pressed together over thousands of years. Tiny bubbles of air are trapped in the ice. By studying them, scientists can measure what Earth's air was like more than 100,000 years ago.

The ice slowly flows toward the coast. Fast rivers of ice called ice streams carry most of the ice that leaves the continent, some moving more than 1,000 meters a year. At the edges, floating ice shelves break off as icebergs, a natural part of a glacier's life.

The ice sheet builds up by the accumulation and compression of snow and frost over thousands of years; trapped air bubbles let scientists measure atmospheric conditions from over 100,000 years ago (BAS). Ice streams such as Thwaites Glacier make up around 10% of the ice sheet but carry most of the ice leaving the continent, some at over 1,000 m a year. Ice shelves fringe much of the coast and calve icebergs, a natural part of the glacier life cycle.

The Transantarctic Mountains divide East from West Antarctica. In the east the ice is thicker and mostly rests on bedrock above sea level; in the west the ice is thinner and much of the bedrock lies below sea level, which BAS says makes West Antarctica significantly more vulnerable to warming ocean water.

Antarctica is very, very cold.

In the middle, very little snow falls. Strong winds rush down from the high land to the coast.

The lowest temperature ever recorded on Earth, −89.2 °C, was measured at Vostok station in Antarctica. A strong ocean current flows all the way around the continent and helps keep warm water and weather away.

Near the coast several meters of snow can fall in a year, but in the middle only a few centimeters fall. That is why much of Antarctica counts as a desert. Winds called katabatic winds flow down from the high plateau and bring frequent gales to the coast.

Vostok station holds Earth's lowest recorded temperature, −89.2 °C. Because Antarctica is unconnected to any other continent, the Antarctic Circumpolar Current circles it and helps isolate it from warm water and weather (BAS). Snowfall ranges from several meters a year near the coasts to only centimeters in the interior, so much of the continent is classed as a desert, and katabatic winds flowing down from the high plateaus bring frequent gales to the coast.

BAS scientists discovered the Antarctic ozone hole, a seasonal thinning of the ozone layer caused by CFCs and halons; the discovery led to the 1987 Montreal Protocol. BAS says a slow recovery is underway, with full repair not expected until around 2070.

Most animals in Antarctica live in or near the sea.

Emperor penguins are the biggest penguins. The dad keeps the egg warm for nine weeks. Tiny krill are food for whales, seals and penguins.

Most of Antarctica's animals live in or around its icy waters. Only two kinds of penguin, the emperor and the Adélie, truly belong to the continent itself. Emperor penguins are the largest. They breed in the coldest, darkest months of winter, and the male keeps the single egg warm for nine weeks without eating.

Whales, leopard seals, Weddell seals and elephant seals live in the Southern Ocean. Many of them depend on krill, small shrimp-like animals that gather in vast swarms. On land, life is sparse: mosses, lichens, liverworts and tiny animals such as springtails and nematodes.

Most of Antarctica's animal life is marine, in a Southern Ocean food web that BAS calls relatively simple. Antarctic krill, a small crustacean that forms dense swarms, feeds most of the larger animals, and its fishery is managed internationally. Of six major penguin species, only the emperor and Adélie are truly native to the continent; the emperor, the largest, breeds in winter and the male incubates the single egg for 9 weeks without eating, living on fat reserves.

Antarctic fish carry antifreeze glycoproteins in their blood, and icefish have no red blood cells. On land there are no naturally occurring mammals, reptiles or amphibians, but there are mosses, lichens and liverworts, the 1–2 mm Antarctic springtail with its own antifreeze, and nematodes in the coldest deserts.

Antarctica has no native people. Scientists come to study it.

Many countries signed an agreement about Antarctica. It says Antarctica is used only for peace and science.

Antarctica has no native population. Scientists work at research stations there, such as Britain's Halley and Rothera stations, where they study the air and the sky with radars, lasers and balloons.

In 1959, twelve countries whose scientists had worked in Antarctica signed the Antarctic Treaty. It says Antarctica may be used for peaceful purposes only, and that scientists must be free to research and share their results. Today 58 countries are part of the Treaty. In 1991 they agreed to protect it as a natural reserve for peace and science, and to ban mining.

Antarctica has no native population, so place names are proposed by Antarctic Treaty countries and managed by international committees (BAS). The Antarctic Treaty was signed in Washington on 1 December 1959 by the twelve countries whose scientists had been active there during the International Geophysical Year of 1957–58; it entered into force in 1961 and now has 58 Parties. Its first articles state that Antarctica shall be used for peaceful purposes only and that freedom of scientific investigation shall continue, with results exchanged and made freely available.

The Protocol on Environmental Protection, adopted in Madrid in 1991, commits the Parties to comprehensive protection of the Antarctic environment, designates Antarctica as a natural reserve devoted to peace and science, and prohibits all activities relating to mineral resources except scientific research.

Some people visit Antarctica on ships.

They stay away from the animals and never feed them. They take nothing home and leave nothing behind.

More than 100,000 tourists now visit Antarctica each year, most of them by ship to the Antarctic Peninsula in the southern summer, from October to April.

Visitors must follow guidelines agreed by the Treaty countries. Keep at least 5 meters from animals on land and give them the right of way. Never feed them. Clean boots and clothes so no seeds or soil are carried in, and don't step on mosses or lichens. Take no souvenirs, not even a feather or a rock, and be ready for severe, changeable weather.

Tourism, mostly by ship, has grown from a few hundred visitors each austral summer in the early 1990s to over 100,000 passengers a year; about 98% of tourism voyages go to the Antarctic Peninsula during the seven-month season from October to April (Antarctic Treaty Secretariat).

The General Guidelines for Visitors, in the Resolution 4 (2021) version that the Antarctic Treaty Secretariat links (it says Resolution 4 (2025) updated them), ask visitors to keep at least 5 m from wildlife on land, more where needed, to stay outside colony margins, to give animals the right of way, not to fly drones near wildlife, not to feed animals, and not to walk on moss beds or lichen-covered rocks. Boots, clothes and equipment must be cleaned to prevent bringing in non-native species and disease. Souvenirs, including feathers, bones, eggs, rocks and fossils, may not be taken, and visitors must be prepared for severe and changeable weather.