There are 13 climatic zones on Earth. The distribution criteria for these zones depend on two factors: the amount of solar radiation and the prevailing air masses.
Highlights and geographical location
The equatorial belt is the central belt of the Earth. It is located in the equator, and therefore received this name. This belt is the only one of 13 that has the ability to interrupt, that is, it does not completely encircle the Earth, like other climatic zones. On both sides of the equatorial are subequatorial zones of the Northern and Southern Hemisphere. Coordinates: from 5 ° –8 ° s. w. up to 4 ° –11 ° S w.
Regional division
The equatorial belt is considered constant (main) - this means that throughout the year the weather and climate do not change in the territory, the prevailing air masses are the same - equatorial. This easily explains the geographical location. The equatorial belt belongs to three regions in which a special invariable climate is established:
- Continent South America within the Amazon Lowland.
- Mainland Africa: its equatorial part and the Gulf of Guinea.
- Large territory and the nearest water area of the Great Sunda Islands.
Climate basics
The climatic conditions of this belt are the same. They are characterized by:
- constantly high temperatures;
- single season of the year (summer);
- heavy rainfall (the highest rates on the planet);
- the predominance of equatorial air masses, which are affected by geographical location;
- the equatorial belt is characterized by increased humidity;
- weak, short-term winds;
- a wide variety of flora and fauna;
- unfavorable conditions for human habitation.
Climatic features
Monthly average temperatures of the equatorial belt vary within + 24 ° ... + 28 ° C. This constant figure is due to the equally high position of the Sun relative to the equator. For this reason, the seasons are invisible here, and the difference in lowering and increasing temperatures is only 2 ° C (the lowest indicator on Earth). The radiation balance of the region is 70-90 kcal / cm 2 per year. In the oceans, it rises to 120 kcal / cm 2 per year. In this region they are calm, they are calm. The atmospheric pressure of the equatorial belt is low.
Tropical trade winds act on this region on both sides of the equator, creating a constant flow of moist air here. Relative humidity in this zone varies between 80-95%. These two reasons (humidity and high temperatures) cause afternoon rainfall in the territories. The average annual rainfall in the equatorial belt is 2,000-3,000 mm (on the slopes of the mountains this figure rises to 10,000 mm / year), which makes these regions the wettest on the planet. High humidity occurs due to the predominance of precipitation over evaporation (per 1,000 mm). They condense in the lower layers of the troposphere.
Features of relief and soil
In the equatorial belt, geomorphological processes are especially intensely distinguished. A striking example is the equatorial belt of Africa. A common feature for the region is a powerful weathering crust:
- for flat areas lateral erosion is characteristic;
- river valleys are wide, have flooded floodplains;
- in mountainous areas, river valleys, on the contrary, are narrow and deep;
- landslides are often.
The soils of the region are acidic, ferrallite. They are poor, the humus content is not more than 3%, and when plowing or cutting down forests, they generally lose their fertility over time.
The features of the equatorial belt are the presence of a wide and powerful hydrological system. It is within this region that the most full-flowing river of the planet is located - the Amazon.
Vegetable world
The climate of the belt creates ideal conditions for the growth of evergreen equatorial forests of high humidity. Such a forest is called a gilea (in South America it is a selva, or “rain forest”). These stands are characterized by a long history, the widest biodiversity, a large number of endemic species. More than half of all plants and animals of the planet live and grow in gileas; there is an opinion that thousands of species remain unidentified. The features of the equatorial belt are that moist forests consist of several tiers. The topmost are trees. They have a high smooth trunk, horizontal rhizome. The middle tier is represented by lianas. Also, you can often find useful (production and household) species - cocoa, rubber, breadfruit, plants with colored woods.
Animal world
The equatorial belt of the Earth is a unique place for life of various representatives of the fauna. They are represented by a huge number of species. Most of them have adapted to live here on trees and their crowns. A large number of monkeys, sloths, anteaters, capuchins, wood porcupines, langurs, possums, bats, lizards, frogs and snakes are found on the territory. Of land animals, rhinos, hippos, elephants, and tapirs are common here. Of the carnivores - only representatives of cats - leopards and jaguars, which are also adapted for life on trees. In addition, the equatorial forests are an ideal place to live with a variety of birds and insects. Their characteristic feature in the region is that they all have a bright, “poisonous” color.
Environmental problems
The equatorial belt of the Earth is currently undergoing strong human intervention. And this leads to inevitable environmental changes. And it is worth noting that for the worse. The well-known fact that forests are “light” planets. The largest share is assumed by the wet equatorial stands. But in recent years there have been catastrophic changes in the territorial composition of forests. They are anthropogenic in nature. Most of the marginal trees are cut down, many species of animals are exterminated. Part of the deforestation is replaced by coffee or other plantations.
Human conditions
However, despite all the suitable factors for the living and distribution of representatives of flora and fauna here, the equatorial belt is extremely unfavorable for people living here. This, of course, is influenced by its geographical location. The equatorial belt is characterized by high humidity and constant hot temperature. And these factors, in turn, have a negative impact on human health. In addition, it is these conditions that are ideal for the formation of natural foci of dangerous infections. Also in the equatorial belt there is a huge number of poisonous insects, animals and plants.
Equatorial Belt Countries
Nevertheless, the territory of some countries falls on the equatorial climatic zone. In South America, this region covers the eastern part of Brazil, Ecuador, Uganda. In Africa, these are the countries of Congo, Gabon, Kenya. In the island part - Sunda Islands, about. New Guinea, Fr. Sri Lanka and the Malacca Peninsula (Indonesia).