During certain seasons, gravity forces fron the moon and the Earth's rotation create strong currents. The moon pushes water away fron the surface. This surface water is replaced with water that rises fron deep down in the ocean. Water at the bottom of the ocean has a lot of nutrients. When these currents rise from the ocean bottom to the surface, the process is called upwelling. The main benefit of upwelling is that fish and marine life can esily be found on the surface.