In physical terms, the current is the movement of a liquid in relation to its environment. Concretely this means for you as a diver the movement of the ocean or the lake.
Different types of current
Thereby, there are two different types. On one hand there is the laminar and on the other hand there is the turbulent current. What do these terms mean?
Laminar: Water moves in different layers and by doing so it does not create vortex or waves. The surface seems quiet then, while the layers laying underneath it can definitely move. For you as a diver this means: Even if the surface seems quiet, you should be careful. Because suddenly under the surface of water you may possibly be carried away.
Turbulent: Here there are no clear layers in the water, but rather vortexes or waves are created, which the different water layers are mixed with. Particularly in case of high current speeds or uneven ground, such turbulences can arise. This type as well can be unpredictable, because you can possibly be pulled upwards or downwards.
In general you can also use the movement of water for yourself, for example when drift diving.
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