A Mediterranean climate is one that resembles the climate of the lands in the Mediterranean Basin, which includes over half of the area with this climate type world-wide. In addition to the areas surrounding the Mediterranean Sea, this climate type prevails in parts of western North America, in parts of Western and South Australia, in southwestern South Africa and in parts of central Chile.

The climate is characterized by hot, dry summers and cool, wet winters. For example, the city of Perth, Australia, in the southern hemisphere winter months of June-August, experiences 450 mm (17.7 inches) of rainfall and an average daily minimum of 8°C (46°F). Meanwhile during the summer months of December to February the city only averages 32mm (1.3 inches).

Mediterranean climate zones are associated with the five large subtropical high pressure cells of the oceans, the Azores High, South Atlantic High, North Pacific High, South Pacific High, and Indian Ocean High. These high pressure cells shift polarward in the summer and equatorward in the winter, playing a major role in the formation of the world's tropical deserts and the zones of Mediterranean climate polarward of the deserts. For example, the Azores High is associated with the Sahara Desert and the Mediterranean Basin's climate. The South Atlantic High is similarly associated with the Namib Desert and the Mediterranean climate of the Western part of South Africa. The North Pacific High is related to the Sonoran Desert and California's climate, while the South Pacific High is related to the Atacama Desert and central Chile's climate, and the Indian Ocean High is related to the deserts of western Australia (Great Sandy Desert, Great Victoria Desert, and Gibson Desert) and the Mediterranean climate of southwest and south-central Australia.

The Mediterranean forests, woodlands, and shrub biome is closely associated with Mediterranean climate zones. Particularly distinctive of the climate are sclerophyll shrublands, called maquis in the Mediterranean Basin, chaparral in California, matorral in Chile, fynbos in South Africa, and mallee and kwongan shrublands in Australia. Aquatic communities in Mediterranean climate regions are adapted to a yearly cycle in which abiotic (environmental) controls of stream populations and community structure dominate during floods, biotic (e.g. competition and predation) controls become increasingly important as the discharge declines, and environmental controls regain dominance as environmental conditions become very harsh (i.e. hot and dry); as a result, these communities are well suited to recover from droughts, floods, and fires .