These polar zones include the Arctic region in the Northern Hemisphere and the Antarctic region in the Southern Hemisphere. Together, the Arctic and Antarctic play a central role in Earth's climate and global climate systems.

Although both polar regions receive limited sunlight for much of the year, they differ in geography. The northern polar region centers on a frozen ocean, while the southern polar region is a frozen continent surrounded by ocean.

The Arctic: An Ocean Surrounded by Land

The Antarctic: A Continent Surrounded by Ocean

Governance and Global Impact

Why the Polar Regions Matter

The Arctic region in the Northern Hemisphere lies within the Arctic Circle, one of the polar circles defined by Earth’s tilt and the summer solstice. At its heart sits the Arctic Ocean, covered by shifting pack ice and seasonal Arctic sea ice.

Unlike Antarctica, the Arctic is an ocean surrounded by land mass in northern Canada, northern Europe, and parts of Russia. The Canadian Arctic, Greenland, and and state of Alaska border Arctic waters.

Sea ice extent in the Arctic changes with the seasons. During winter, sea ice spreads across much of the frozen ocean. In summer, rising temperatures shrink Arctic sea ice, exposing dark ocean water.

This shift reduces the ice surface that reflects the sun’s energy, a process known as ice albedo feedback. As a result, Arctic amplification describes the observed phenomenon in which the Arctic climate warms faster than many other regions on ’s surface.

The Greenland ice sheet, one of the largest ice sheets outside Antarctica, adds another layer to the Arctic system. Melting ice contributes to sea level rise and can influence large-scale North Atlantic ocean circulation.

Wildlife thrives despite the extreme climate. Polar bears hunt on sea ice, while Arctic foxes roam coastal tundra. The Arctic Council coordinates cooperation among nations on issues ranging from natural resources to environmental protection.

The Antarctic region centers on the Antarctic continent, a continent largely covered by thick ice sheets. Unlike the Arctic, Antarctica is a land mass surrounded by the Southern Ocean.

The Antarctic Peninsula extends toward South America and has experienced a widespread, strong warming trend. The continent surrounded by ocean helps drive powerful ocean currents near the Antarctic Convergence, where cold Antarctic waters meet warmer seas.

Antarctic sea ice extent expands dramatically in winter, forming a ring of pack ice around the frozen continent. In summer, much of this sea ice melts back, and Antarctic sea ice shows large natural variability.

Antarctic seals, penguins, and other Antarctic marine living resources depend on stable sea ice conditions. The Ross Sea and surrounding continental shelf support rich marine ecosystems shaped by the extreme cold and seasonal light cycles.

International law plays a major role in the southern polar region.

The Antarctic Treaty, signed after the International Geophysical Year, established Antarctica as a zone dedicated to peaceful scientific research. The broader Antarctic Treaty System includes agreements on Antarctic marine living resources and environmental protection.

No single nation governs the Antarctic continent. Instead, countries cooperate under shared rules that limit military activity and prohibit activities relating to Antarctic mineral resources, except for scientific research.

In the Arctic, governance differs. Nations with territory inside the Arctic Circle manage their own lands and waters. As sea ice extent declines, interest in shipping routes and natural resources has increased across the Arctic.

Earth's polar regions act like planetary air conditioners. Bright ice surface areas reflect solar radiation, helping regulate air temperature and stabilize Earth’s climate.

When greenhouse gases such as carbon dioxide build up in the atmosphere, greenhouse gas concentrations trap more heat. Rising temperatures in the polar zones influence global climate patterns, sea level, and weather far beyond the North and South Poles.

Scientists monitor air temperature, ice sheets, and sea ice extent to understand how Arctic and Antarctic systems respond to climate change. What happens in these extremely cold regions does not stay there. It can influence ocean currents, storms, and ecosystems across the world.

We created this article in conjunction with AI technology, then made sure it was fact-checked and edited by a HowStuffWorks editor.