# 7.2: Major Gyres & Surface Currents

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Global winds move water along the surface of the ocean in various directions, based on location. In the Northern Hemisphere, the ocean currents move in a clockwise spiral. In the Southern Hemisphere, the ocean currents move in a counter-clockwise spiral. The Coriolis effect is the major source of the direction the water moves in our oceans. Since the Coriolis effect is not present at the equator, neither are the major spirals of surface currents we see north and south of the equator. Instead, Currents in the Northern Hemisphere move along the equator to the West and then change direction. There is an Atlantic Equatorial Current System, a Pacific Equatorial Current System and two Indian Monsoon Gyres. Surface currents vary considerably in strength, width, temperature and depth. The five most notable gyres are as follows: Indian Ocean Gyre, North Atlantic Gyre, North Pacific Gyre, South Atlantic Gyre, and South Pacific Gyre. Global gyres contain both cold water from the deep ocean and warm water from the surface currents.

Look at these links for better visuals on movement:

https://svs.gsfc.nasa.gov/cgi-bin/details.cgi?aid=10841 (Perpetual Ocean: NASA)