What are types of Ocean Currents ?

1. Primary Forces-–start the water moving

The primary forces are:

1. Solar Heating
2. Winds
3. Gravity
4. Coriolis  

     2.Secondary Forces–influence where the currents flow

1. Surface Circulation

Solar heating cause water to expand. Near the equator the water is about 8 centimeters high than in middle latitudes.

This cause a very slight slope and water wants to flow down the slope.

Winds blowing on the surface of the ocean push the water. Friction is the coupling between the wind and the water’s surface.

A wind blowing for 10 hours across the ocean will cause the surface waters to flow at about 2% of the wind speed.

Water will pile up in the direction the wind is blowing.Gravity will tend to pull the water down the “hill” or pile of water against the pressure gradient.