Antarctica

The frozen continent surrounding the South Pole

Overview

Antarctica is Earth's southernmost continent. It surrounds the geographic South Pole and is almost completely covered by a vast layer of ice.

Antarctica is the fifth-largest continent by area and is the coldest, driest and windiest continent on Earth. Unlike the other continents, it has no permanent indigenous human population.

The continent is surrounded by the Southern Ocean and is separated from South America by the Drake Passage. Antarctica plays an important role in the global climate system, ocean circulation and Earth's freshwater cycle.

Key fact: Antarctica contains approximately 90% of the world's surface freshwater in the form of ice.

Geography of Antarctica

Antarctica is centred approximately on the South Pole and is surrounded by the Southern Ocean. Its geography consists of a continental landmass, extensive ice shelves, mountain systems, glaciers and coastal regions.

Major geographical features

The continent is commonly divided into East Antarctica and West Antarctica, separated approximately by the Transantarctic Mountains.

East Antarctica and West Antarctica

East Antarctica

East Antarctica contains a large, relatively high continental landmass covered by the East Antarctic Ice Sheet. Much of its ice rests on bedrock above sea level.

West Antarctica

West Antarctica includes the Antarctic Peninsula and a large region of ice-covered land and marine-based ice. The West Antarctic Ice Sheet is particularly important in studies of long-term sea-level change.

The Antarctic Ice Sheet

Antarctica is covered by the largest single mass of ice on Earth. The Antarctic Ice Sheet contains enormous quantities of frozen freshwater accumulated from snowfall over very long periods.

In places, the ice is several kilometres thick. The weight of the ice depresses the underlying continental crust.

Ice shelves

Ice shelves are floating extensions of the continental ice sheet. They form where glaciers and ice flow from the land onto the ocean and continue floating over seawater.

Important Antarctic ice shelves include the Ross Ice Shelf and the Filchner-Ronne Ice Shelf.

Glaciers

Antarctic glaciers transport ice from the interior of the continent towards the coast. Some glaciers are enormous, including the Thwaites Glacier and Pine Island Glacier in West Antarctica.

Mountains of Antarctica

Antarctica contains extensive mountain systems, many of which are hidden or partly buried beneath ice.

Mountain System / Peak Location Significance
Transantarctic Mountains East and West Antarctica Major mountain system crossing the continent.
Mount Vinson Ellsworth Mountains Highest mountain in Antarctica.
Ellsworth Mountains West Antarctica Major Antarctic mountain range.
Gamburtsev Mountains East Antarctica Large mountain range largely buried beneath the ice sheet.
Mount Erebus Ross Island Active volcano and one of the world's southernmost active volcanoes.

Climate

Antarctica has the coldest climate on Earth. The interior is an extremely cold polar desert with very little precipitation.

Temperature

Temperatures in the Antarctic interior can fall below -70 °C during winter. Coastal areas are generally less cold than the high interior plateau.

Precipitation

Antarctica is technically a desert because precipitation is extremely low over much of the continent. Most precipitation occurs as snow.

Katabatic winds

Very cold, dense air can flow downhill from the elevated Antarctic interior towards the coast. These powerful downslope winds are known as katabatic winds.

Polar day and polar night

Because Antarctica surrounds the South Pole, it experiences extreme seasonal variations in daylight. Near the South Pole, the Sun remains above the horizon for approximately six months and below the horizon for approximately six months.

The Southern Ocean

Antarctica is surrounded by the Southern Ocean. This ocean is a major component of the global ocean circulation system.

The Antarctic Circumpolar Current flows around Antarctica from west to east and connects the Atlantic, Pacific and Indian Ocean systems.

Important Antarctic Seas

Antarctic Sea Ice

Sea ice forms when seawater freezes around Antarctica during the winter. Its extent varies dramatically between summer and winter.

Sea ice is important because it affects ocean circulation, marine ecosystems, the exchange of heat between the ocean and atmosphere, and Earth's surface reflectivity.

Wildlife

Antarctica has relatively little terrestrial biodiversity, but its surrounding marine ecosystem supports an enormous variety of organisms.

Penguins

Marine mammals

Birds

Krill and the Antarctic Food Web

Antarctic krill are small crustaceans that form one of the foundations of the Southern Ocean food web.

Krill are eaten by whales, seals, penguins, fish and seabirds. Their abundance therefore has major implications for the wider Antarctic marine ecosystem.

Food-web example: Phytoplankton → Krill → Fish / Penguins / Seals / Whales

Life Beneath the Antarctic Ice

Antarctica is not biologically empty. Microorganisms and other organisms can survive in extremely cold environments, including environments beneath glaciers and within Antarctic ice.

Scientists have also identified extensive subglacial lakes and water systems beneath the Antarctic Ice Sheet. These environments provide important opportunities for research into life in extreme environments.

Scientific Research

Antarctica is one of the world's most important natural laboratories. Scientists from many countries conduct research on the continent and in the surrounding Southern Ocean.

Major areas of research

Antarctic Astronomy

Antarctica provides unusual conditions for astronomical research. The dry, cold atmosphere and long periods of darkness can provide favourable conditions for certain types of observations.

Research has included observations of the cosmic microwave background, infrared astronomy, neutrinos and high-energy astrophysical phenomena.

IceCube Neutrino Observatory

The IceCube Neutrino Observatory is a major scientific facility embedded within the Antarctic ice near the Amundsen-Scott South Pole Station. It detects neutrinos interacting within the ice.

Antarctic Research Stations

Many countries operate scientific research stations in Antarctica. Some are occupied throughout the year, while others operate mainly during the Antarctic summer.

Research Station Country Location / Feature
Amundsen-Scott South Pole Station United States Located at the geographic South Pole
McMurdo Station United States Ross Island
Halley Research Station United Kingdom Brunt Ice Shelf
Rothera Research Station United Kingdom Adelaide Island
Concordia Station France / Italy East Antarctic interior
Vostok Station Russia East Antarctic interior

History of Antarctic Exploration

Antarctica was not permanently inhabited by humans before modern exploration. European and other explorers gradually established the existence and geography of the southern continent.

James Cook

Captain James Cook crossed the Antarctic Circle during his voyages in the eighteenth century and demonstrated that a large southern continent was not easily accessible through the regions he explored.

Roald Amundsen

Norwegian explorer Roald Amundsen led the first expedition to reach the geographic South Pole in December 1911.

Robert Falcon Scott

British explorer Robert Falcon Scott led the Terra Nova Expedition, reaching the South Pole shortly after Amundsen's expedition. Scott and four companions died during their return journey.

Ernest Shackleton

Ernest Shackleton became one of the best-known figures in Antarctic exploration. His Imperial Trans-Antarctic Expedition of 1914–1917 became famous for its survival and leadership story following the loss of the expedition ship Endurance.

The Antarctic Treaty

Antarctica is governed by an international treaty system that emphasises peaceful use and scientific cooperation.

The Antarctic Treaty was signed in 1959 and entered into force in 1961. It established Antarctica as a region dedicated to peaceful purposes and scientific investigation.

The wider Antarctic Treaty System includes agreements concerning environmental protection, marine living resources and other Antarctic activities.

No Permanent Population

Antarctica has no permanent indigenous population and no permanent civilian cities. Scientists, engineers, technicians and support personnel live at research stations for varying periods.

The number of people present changes substantially between the Antarctic summer and winter.

Antarctica and Global Climate

Antarctica is an essential component of the Earth's climate system. Its enormous ice sheet reflects a substantial proportion of incoming solar radiation and stores a vast quantity of freshwater.

Changes in the Antarctic ice sheet, ice shelves and Southern Ocean can influence global sea level, ocean circulation and climate.

Environmental Challenges

Antarctica is protected by international agreements, but it remains vulnerable to changes occurring throughout the global climate system.

Ice-sheet change

Scientists monitor changes in Antarctic ice mass, glacier flow and ice-shelf stability to understand their implications for future sea-level rise.

Ocean warming

Changes in Southern Ocean temperature and circulation can affect Antarctic ice shelves and marine ecosystems.

Wildlife

Changes in sea ice and food availability can affect penguins, seals, whales and other Antarctic species.

Human activity

Scientific research, tourism, shipping and other activities require careful environmental management in order to protect Antarctica's fragile ecosystems.

Antarctica and Sea-Level Rise

The Antarctic Ice Sheet contains enough ice to produce a very large global sea-level rise if it were eventually lost. Such a change would occur over very long timescales, but changes in Antarctic ice loss are an important component of modern climate research.

Scientists use satellites, aircraft, GPS measurements, radar, ice cores, ocean observations and computer models to study Antarctic ice dynamics.

Antarctic Ice Cores

Ice cores drilled from the Antarctic ice sheet provide an important record of Earth's past climate and atmosphere.

Air bubbles trapped within ancient ice contain samples of past atmospheric gases. Chemical and physical properties of the ice provide additional information about past temperature, volcanic activity, dust and atmospheric composition.

Quick Facts About Antarctica

Feature Information
Continent Antarctica
Location Southern Hemisphere, surrounding the South Pole
Approximate area 14 million km², varying seasonally with sea ice
Highest mountain Mount Vinson
Highest point Mount Vinson, approximately 4,892 m
Coldest continent Yes
Driest continent Yes, overall
Windiest continent Yes
Permanent population None
Major surrounding ocean Southern Ocean
Major ice sheet Antarctic Ice Sheet
Major active volcano Mount Erebus
Major scientific facility Amundsen-Scott South Pole Station

Conclusion

Antarctica is a unique continent dominated by ice, extreme cold and a highly specialised environment. Its mountains, glaciers, ice shelves and surrounding Southern Ocean form one of the most important physical systems on Earth.

The continent is also a major centre for international scientific research. Studies of Antarctic ice, climate, astronomy, oceanography and biology provide valuable information about both Earth's past and its future.

Antarctica's importance extends far beyond the Southern Hemisphere. Its ice sheet, oceans and atmosphere are closely connected with global climate, ocean circulation, ecosystems and sea level.