Answer:
The same thing!
Deep Currents
Occur when the density of the water increases.
Density is based on two main things it is the civility is how much salt and other solids are in it and it is also the temperature of the water.The lower the temperature the lower the dense the water becomes.
The denser the water the more it was to go down.
The less dense the water wants to rise.
The temperature is what causes the dense.
Deep current:A streamline movement of ocean water far below the surface.