What is the El Nino phenomenon?

El Nino, also known as El Nino phenomenon, and another phenomenon, Southern Oscillation, are called ENSO. This is a term used by fishermen in Peru and Ecuador to refer to abnormal climate phenomena. ?

It mainly refers to the abnormal continuous warming of seawater temperature in the tropical ocean in the eastern and central Pacific Ocean, which changes the global climate pattern, causing drought in some areas and excessive rainfall in some areas.

The monsoon air flow in the tropical Pacific moved from America to Asia, keeping the surface of the Pacific warm and bringing tropical rainfall to Indonesia. However, this pattern is disrupted every 2 ~ 7 years, which reverses the wind direction and ocean currents;

The heat flow in the surface layer of the Pacific turned eastward to America, taking away tropical rainfall and causing a large area of drought on the earth. This is the "El Nino phenomenon".

Extended data:

cause

Weakening of southeast wind

When the southeast wind blowing near the equator in the southern hemisphere weakens, the cold water flooding in the Pacific will be reduced or stopped, which will lead to the abnormal warming of sea water temperature in a large range, and the abnormal traditional equatorial current and atmospheric circulation will lead to the abnormal precipitation in some areas along the Pacific coast.

Under normal circumstances, the northeast trade wind blows near the equator in the northern hemisphere and the southeast trade wind blows near the equator in the southern hemisphere. The trade winds drive the seawater to flow from east to west, forming the North Equatorial Warm Current and the South Equatorial Warm Current respectively.

The seawater flowing out of the equatorial eastern Pacific is supplemented by the upwelling of the lower layer, which makes the lower layer of cold water in this area flood, and the water temperature is lower than the surrounding area, forming a temperature difference between the east and the west.

References:

Baidu encyclopedia-El Nino phenomenon