Southern Hemisphere

The Southern Hemisphere is the half of Earth located south of the equator. It includes all or parts of five continents: all of Antarctica and Oceania, roughly 90% of South America, about one-third of Africa, and some islands off mainland Asia. Its oceans are the entire Southern Ocean, most of the Indian Ocean, and the South Atlantic and South Pacific.

Population

New Zealand and most Pacific Islands in Oceania are also here. Water covers 80.9% of its surface, compared to 60.7% in the Northern Hemisphere, and it holds 32.7% of Earth’s land. Over 850 million people live here, about 10–12% of the global population.

Because of Earth’s axial tilt, summer runs from December to February and winter from June to August. The vernal equinox occurs around September 22 or 23, and the autumnal equinox around March 20 or 21. The South Pole sits at the center of this hemisphere.

Characteristics

Southern Hemisphere climates are generally milder than those at similar northern latitudes, except in Antarctica, which is colder than the Arctic. This is due to much more ocean and less land—water heats and cools more slowly—along with oceanic heat transfer and differences in greenhouse trapping. The lowest temperature ever recorded on Earth was at Antarctica’s Vostok Station: −89.2 °C (−128.6 °F) on July 21, 1983.

The Northern Hemisphere’s record low is −69.6 °C (−93.3 °F) in Greenland on December 22, 1991. The Southern Hemisphere’s highest recorded temperature is 50.7 °C (123.3 °F), tied between Oodnadatta, South Australia (January 2, 1960) and Onslow, Western Australia (January 13, 2022). A 1922 reading of 58 °C (136.4 °F) in El Azizia, Libya, was long cited as the world record but was decertified in 2012 due to measurement errors; the 56.7 °C (134 °F) in Death Valley, California (July 10, 1913) replaced it.

In the Southern Hemisphere, the Sun travels from east to west through the north, though north of the Tropic of Capricorn it can be directly overhead or due south at midday. The Sun moves right to left across the northern sky, opposite the left-to-right motion seen in the Northern Hemisphere. Shadows turn anticlockwise during the day, and sundials have hours increasing anticlockwise.

During solar eclipses viewed south of the Tropic of Capricorn, the Moon moves left to right across the Sun; north of the Tropic of Cancer, it moves right to left. The Coriolis effect makes cyclones and tropical storms spin clockwise here, versus anticlockwise in the Northern Hemisphere. The southern temperate zone is almost entirely ocean.

The night sky is excellent for viewing: the Sagittarius constellation, which contains the galactic center, is a southern constellation, along with both Magellanic Clouds. Clearer skies and brighter, more numerous stars are common. Air pollution is significantly lower than in the Northern Hemisphere, because most of Earth’s population and major industrial powers—including high-emission countries like China and India—are in the north. The 1986 Chernobyl nuclear disaster did not affect the Southern Hemisphere; small traces were found in northern locations like the United States, Canada, and Japan, but none in the south.

Flora and Fauna

Forests here have unique features. Chile and Australia share beech species of the genus Nothofagus, while New Zealand has closely related Lophozonia and Fuscospora. Eucalyptus, native to Australia, is now planted in Southern Africa and Latin America for pulp and increasingly for biofuel. Some African animals, like chimpanzees and gorillas, live in both hemispheres.

Eastern gorillas are native to three Southern Hemisphere countries: Rwanda (entirely below the equator) and the Democratic Republic of the Congo and Uganda (trans-hemispheric). Western gorillas are found in Angola, the Democratic Republic of the Congo, Equatorial Guinea, Gabon, and the Republic of the Congo, as well as in Northern Hemisphere countries Cameroon and Nigeria. The common chimpanzee ranges across both hemispheres, from Guinea and Senegal in the west to Tanzania and Uganda in the east, with populations in several countries partly or wholly south of the equator, including Burundi, the Democratic Republic of the Congo, Gabon, and the Republic of the Congo. The bonobo species is found only in the Southern Hemisphere.