Why does the tropical desert climate on the west side of South America extend from north to south?

1. The Andes are located on the west coast of the South American continent, which makes the tropical desert climate distribution narrow.

2. There is a Peruvian cold current in the west, which has the effect of cooling and reducing humidity.

3. Being on the leeward slope of the southeast trade wind, there is little precipitation. The high Andes hinder the atmospheric circulation.

Extended data:

The main distribution of tropical desert climate:

The tropical desert climate is mainly distributed in the mainland or the west coast of the mainland near the Tropic of Cancer, mainly in the narrow areas of North Africa, West Asia, central and western Australia and western South America, generally in the mainland and west coast near the Tropic of Cancer. Take North Africa, Arabian Peninsula in Asia and desert areas in Australia as typical examples.

It is characterized by high annual average temperature, large annual temperature difference, large daily temperature difference and scarce precipitation. The annual precipitation is generally below 250 mm, and in many areas it is only tens or even several millimeters. Precipitation varies greatly, and it often doesn't rain for several years.

It is controlled by subtropical high pressure area or trade wind area, and it is controlled by tropical continental air mass all the year round, with little rain. The annual precipitation is about 100 mm, and in some places it is only tens of millimeters or even less, and the evapotranspiration may be more than 20 times larger than the precipitation.

The annual average temperature is higher than 18℃, and it is very hot in summer. The average temperature in the hottest month is mostly 30℃-35℃, the absolute maximum temperature in some places is as high as 58℃, the maximum temperature on the ground is above 80℃, and the average temperature in Leng Yue is not lower than 10℃. The daily temperature difference can reach 35℃-40℃, and the minimum temperature at night can be reduced to about 0℃. Less clouds, strong sunshine and abundant solar energy resources.

The contradiction between heat and water is prominent. The distribution and formation of the world's great deserts are closely related to the tropical dry climate. The natural vegetation is desert.

Sahara Desert in Africa, kalahari desert, Arabian Desert in Southwest Asia, thar desert, deserts in western and central Australia, deserts in Baja Colorado and California in North America and Atacama Desert in South America all have typical tropical desert climate. The tropical desert climate zone is on the north and south sides of the tropical grassland climate zone.

The air pressure in these places is high and the weather is stable. The wind always blows from the land to the sea, but the humid air from the sea can't enter the land, so the rainfall is very small and very dry. The rocks on the ground are weathered to form tiny sand grains, which float and accumulate with the wind, forming sand dunes, which are widely distributed and become vast deserts.

In some places, the weathering speed of rocks is slow, forming large gravel, which is desert. The area of desert on the earth is very vast, and there is a trend of further expansion.

Baidu Encyclopedia-Tropical Desert Climate