List the steps that show how the sun provides the energy for surface ocean currents

"The sun affects ocean currents in a couple of ways. When the sun heats water at the surface of the ocean, some of the water will evaporate and increase the concentration of salt in the water at the surface. Increased salt concentration of salt means the water is more "dense". But if you think about it, things that are more dense tend to sit below things that are less dense. For example, think about putting a rock in a tank of water. The rock will sink to the bottom of the tank, because it is more dense than the water. For the same reason, the denser water with higher salt that formed because of evaporation will start to sink, and less dense water will rise and take its place. This process, combined with fresh water flowing into the ocean from river and changing the salt concentration of the water, contributes to ocean currents. In certain parts of the oceans, the dense water will sink very deeply and form deep water masses. These will flow very slowly in the deep ocean currents. 

The sun also heats up the air in the atmosphere at the equator. This air will move toward the poles and cool over time. In the process wind that occurs due to air currents will induce currents at that surface of the ocean. The currents at the surface are sort of "propagated" down deeper because of differences in the forces on different parts of the water."