The warm current is caused by the low latitude in winter, dry coastal climate, less cloud cover, strong solar radiation and high temperature all the year round in the North Indian Ocean. Most coastal areas have a dry tropical desert climate with no rivers flowing in. As a result, the coast presents a coastal wind, and the seawater accumulates continuously, forming an inshore sinking current, and the surface hot water sinks southward with the wind, forming a warm current.
In summer, with the southwest monsoon blowing, the surface seawater of Arabian Sea flows offshore, while the seawater along the nearby East Africa coast flows to compensate for the lost seawater and form the rising compensation current. It makes the offshore wind appear on the coast, and the cold water in the lower layer overflows, which just goes north with the wind and becomes a cold current from low latitude to high latitude.
I. Cold current
Cold current is a way of seawater movement, which refers to the ocean current from low water temperature to high water temperature. Cold current mostly flows from high latitude to low latitude, which cools and dehumidifies the place where it passes. Most of the ocean currents flowing from high latitude to low latitude, the water temperature of the cold current is lower than that of the area where it reaches, which can reduce the temperature and humidity of the place where it passes.
The water temperature of the cold current itself is lower than the surrounding water temperature. As the messenger of the cold ocean, it flows from high latitude or polar ocean to middle and low latitude, bringing cool breath to the sea it flows through. There are five famous cold currents in the world's oceans: California cold current in the eastern North Pacific, Peru cold current in the eastern South Pacific, Canary cold current in the eastern North Atlantic, Benguela cold current in the eastern South Atlantic and Western Australia cold current in the eastern South Indian Ocean.
In the area where the cold current passes, most coastal areas are accompanied by upwelling. Rich deep-water nutrients are brought to the upper layer with high oxygen content, so these areas are the sea areas where many fish feed and live, and they are natural excellent fishing grounds, such as Peru fishing grounds in western South America. The cold current flows, which lowers the temperature near the sea surface, and the water vapor is easy to condense and form fog, which affects shipping.
Second, the warm current
Warm current, ocean current flowing from low latitude to high latitude. The water temperature of the warm current is higher than that of the area it reaches. The warm current in the ocean contains huge heat energy and its influence on the climate. Warm current can increase the humidity and temperature along the coast, which is more conducive to the growth and development of organisms, and has attracted extensive attention of scientists all over the world, among which the most important ones are the Gulf Stream and Kuroshio.