The sea currents have rules

In 1856, some sailors in distress on a sandy beach in the Atlantic found a tar ball, the asphalt covered a coconut skull, including a goat skin letter with symbols strange is sent from a very far shore. After a long journey, it was expected that the letter would come to a beautiful island, but the waves would bring it to the wasteland.

How did people think about using the sea to deliver letters? For a long time, people have found that, on the sea and deep, seawater flows in a regular direction, like a river on land, called a sea current.

There are many very complicated causes of sea currents. Directional wind like Tin phong and West wind are the main reasons. At the same time, the forces of the Earth rotate, the coastline, the distribution of the island, the sea level, the temperature of the sea water and the salt concentration, . all have a certain influence on the ocean currents.

The currents of the Northern Hemisphere and the Southern Hemisphere are equally symmetrically distributed. On the tropical vice sea of ​​the Northern Hemisphere, the basic ocean current flows clockwise around the tropical deputy high pressure, called the circulatory. At the coast, the sea circulation flows counterclockwise along the coast called the periodic circulation. At sea level 40 degrees or more North, the ocean current flows counterclockwise around the depressive depressions. The direction of the ocean current in the Southern hemisphere flows backwards.

Wind direction map (Photo: maps.weather.com)

The sea currents greatly affect the climate of the regions in the world.First of all , seawater transfers heat several times higher than air, so ocean currents have a great effect in heat transfer between high latitudes and high latitudes, regulating the temperature difference between latitudes. Secondly , because of the temperature difference of hot and cold water currents between the East and West coasts, under the effect of prevailing airflow (wind), the air temperature between the East and West coasts is very different. remarkably, breaking the law as high as the latitude is lower. In addition, hot coastal currents make heavy rain, cold coastal currents make many fogs.

Oceanographers rely on documents such as the path of marine floating objects, sponge journeys, the whereabouts of boat wrecks, different temperatures of seawater, the drift records of boats , direction and speed of flow, ocean current map. In modern times like today there are also precision measuring machines and artificial satellites, people have a better understanding of ocean currents and discover the world with 12 large, several dozen sea currents. save small.

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