Air masses of the equatorial belt. Equatorial climatic zone: characteristic

The central belt of the planet got its name equatorial due to its location on both sides of the equator from 5-8 degrees north to 4-11 degrees south latitude.

Eternal summer

The equatorial belt bounded by the subequatorial belts consists of three areas:

• Continent South America: the lowlands of the Amazon;
• Mainland Africa: the equatorial part; Guinea Bay;
• Part of the Great Sunda Islands and the nearest water area.

Equatorial latitudes encompass both parts of both parts of the world, with the same climatic conditions in both the Northern and Southern Hemispheres.

Formation of equatorial air masses

The amount of heat that the sun gives to the earth's surface is one of the main factors affecting the climate of any place on Earth. The degree of warming up the surface of the planet depends on the angle at which the sun's rays fall on it. The closer to the equator, the more the surface of the Earth warms up, hence the temperature of the surface air increases.

On the territory of the equatorial belt, the angle of incidence of the sun's rays is the highest, so the average annual air temperature in the regions of the equatorial belt is +26 degrees with insignificant differences. The air masses of the equatorial belt, being heated, rise and create an upward movement of air currents.

At the surface of the Earth formed a zone of low atmospheric pressure - equatorial depression. Heated and moist air, which has risen up, becomes saturated and is cooled there. As a result of thermal conversion, a lot of cumulus clouds gather, precipitating in the form of rain.

The air masses of the equatorial belt that form in the depression zone always have a high temperature. Humidity in this area is also increased.

This is the unique equatorial climate belt. The characteristics of air masses are always similar. Since they are formed in a zone of low atmospheric pressure above the land and the ocean, scientists do not subdivide them into marine and continental subtypes of the climate.

Features of air masses

The prevailing air masses of the equatorial belt form the equatorial type of climate, which is characterized by:

• A high constant temperature of air from 24 ⁰ C to 28 ⁰ C with minor differences during the year with a difference of 2-3 ⁰ C. The change of seasons passes unnoticed, year-round dominates the summer. The average temperature in the equatorial belt does not change during the year.
• The abundance of atmospheric precipitation with two maxima of precipitation, corresponding to the zenith position of the Sun, and two minima during solstices. Rains are coming, but unevenly.
• The mode of precipitation in the equatorial belt and their number, dropping over the year, differs for different regions of the equatorial belt.

A typical equatorial climate is characteristic of the Western Amazon and the Congo Basin. In the basin of the Congo, the amount of precipitation in the year is 1200-1500 mm, in some places 2000 mm per year. The area of the Amazonian lowland is much larger than the Congo Basin, air masses of the equatorial belt are formed more intensively. The annual amount of precipitation falls to 2000-3000 mm. This is many times the annual rate.

Equatorial climatic zone: climate characteristic

For the western part of the Andes and the north of the Guinea coast, precipitation of the most abundant precipitation is typical, their number may exceed 5000 mm per year, in some places up to 10,000 mm per year. Such an abundance of precipitation is affected by a strong countercurrent between the trade winds of the north and south. In these areas, the maximum summer precipitation is expressed.

The mode of precipitation in the equatorial belt varies considerably by seasons. The dry period is either absent, or lasts one to two months. A large difference in the amount of precipitation in summer and winter in these regions is due to the dry and dusty West African trade wind Harmatan. From late November to early March, it blows from the Sahara towards the Gulf of Guinea.

Equatorial belt: winds that form the climate

The abundance of atmospheric precipitation is directly related to the intertropical zone of convergence of the trade winds by the zone where the convergence of air currents is observed. The convergence zone extends along the equator, coincides with the zone of low atmospheric pressure and lies most of the year to the north of the equator. In seasons, the resulting shifts in the convergence zone are accompanied by changes that are most noticeable in the Indian Ocean basin.

Here trade winds are replaced by monsoons. Steady winds, depending on the season, change their direction. The strength of the wind can change: from weak to become heavy. In this zone, most of all tropical cyclones are formed. Tropical latitudes are characterized by high atmospheric pressure.

Trade winds and monsoons

In them air streams are formed, which rush to the zone of low pressure - to the equator. Due to the rotation of the Earth, the north-east trade wind near the equator takes the northern direction, and the south-east trade wind - the southern one. When they meet, they form a calm - windless strip. Trade winds are weak air currents blowing along the equator all year round, they are the most stable winds on the planet.

Thus, after the days of the equinox, the maximum precipitation in the equatorial zone falls. A slight decrease in precipitation is observed after the days of solstices. Above the earth's surface, heated by the sun's rays, a cluster of clouds is formed. Usually in the afternoon there are torrential rains accompanied by thunderstorms. Above the sea downpours and thunderstorms go at night, this is the difference between the sea and continental climate.

Atmospheric precipitation falls so much that moisture does not have time to evaporate. The relative humidity is 80-95%. Excess of moisture swamps the soil, contributing to the growth of impassable multi-level equatorial forests. Over the moist forests of equatorial latitudes, the western monsoons are constantly blowing in the summer, and in the winter - the eastern monsoon, in Africa the Guinean monsoon and the monsoon of Indonesia.