The main reason for the occurrence of the current.

The current is an integral part of any body of water, with the exception of closed ones (lakes, swamps, stakes, and others).

If there are different reasons why they are formed, for example:

1. Temperature difference at the bottom of the reservoir;

2. The movement and faults of the lithospheric plates, as a result of which, in addition to the tsunami, currents appear

3. Temperature difference depending on the distance from the equator

But the main reason for continuous currents is the wind. Due to the difference in atmospheric pressure above the water, wind is formed, which sets the direction of the currents. The currents are almost always constant. They are cold and warm.

The situation is different in rivers. There, currents are formed due to the fact that the river always flows downhill. The flow is from top to bottom. From source to mouth.