Subtropics

The subtropical zones or subtropics are geographical and climate zones right next to the tropics. They sit between the tropics and the temperate zones. These zones cover areas from about 23° to 35° to 40° north and south. This area includes the horse latitudes, where the wind is often calm.

Subtropical climates usually have hot summers and mild winters. There are two main types. One is humid subtropical, where it rains mostly in the summer, like in Southeast China and the Southeastern United States. The other is dry summer or Mediterranean climates, where rain falls mostly in the cooler months, like in the Mediterranean Basin or Southern California.

These climates can also be found high up inside the tropics, such as in the southern part of the Mexican Plateau and Da Lat in Vietnam. Many of the world's deserts are in the subtropics because of steady high-pressure systems. Areas near warm oceans often have wet, rainy summers, while areas near cool oceans tend to be dry and foggy. Common plants in subtropical regions include palms, citrus, mango, pistachio, lychee, and avocado.

Definition

See also: List of locations with a subtropical climate

The tropics are found between the Tropic of Cancer and Tropic of Capricorn, at about 23.5° north and south. The subtropics are the areas just beyond the tropics, roughly between 23.5° and 35° north and south.

Scientists have different ways to describe the subtropical climate. One common method is the Trewartha climate classification. This method says a subtropical area has at least eight months where temperatures average above 10°C (50°F) but at least one month where temperatures stay below 18°C (64.4°F). Other ways to classify also exist.

Rainfall

See also: Earth rainfall climatology, Subtropical ridge, Tropical cyclone, Subtropical cyclone, and Wet season

The sun heats Earth most near the equator. This causes warm air to rise and move toward the poles. The air cools and sinks around the 30th parallel in both hemispheres. This creates high-pressure areas called subtropical ridges.

These high-pressure areas often cause dry conditions. They help create many of the world's deserts, like in Southern Africa and along the west coast of South America.

But some subtropical areas get a lot of rain. Places like Australia, the Indo-Gangetic Plain, and parts of South America have wet summers with frequent rainstorms. Their winters are drier. Coastal areas near warm oceans, such as the southeastern United States and Japan, can get heavy rain from tropical cyclones. The Mediterranean climate occurs around the Mediterranean Sea, southwestern Australia, and near Santiago on the west coast of South America. It has wet winters and dry summers.

Flora

The subtropics have warm winters that rarely freeze or snow, which helps plants like palms and citrus trees grow well. Farmers can also grow tropical crops such as mango, lychee, avocado, and aloe vera in these areas. The cooler winters make it easier to protect these crops from pests.

In subtropical areas, you can also find tree ferns (pteridophytes), along with plants like dracaena and yucca. Trees such as apple, pear, and pomegranate also thrive in the subtropics.

Varieties

Main article: Humid subtropical climate

Main article: Mediterranean climate

Main articles: Desert climate and Semi-arid climate

The subtropics have many different climate types. A humid subtropical climate has hot, sticky summers and mild winters. You can find this kind of weather in places like the southeastern United States, parts of China, and northern South Asia.

Another type is the Mediterranean climate, which has warm, dry summers and cooler, rainy winters. This climate is found around the Mediterranean Basin and also in parts of California, South Australia, and central Chile. Some subtropical areas are dry, with very little rain, known as desert or semi-desert climates.