Artic Currents

[kmfkais]

Currents are the circulation system of oceans, which move water from place to place. These movements are controlled by gravity, wind, and the rising and sinking of water in different parts of the world, due to varying temperature. Temperature has a great effect on the density of water. As water warms, it expands and becomes less dense, causing it to rise to the surface. In warm climates this water evaporates quickly, thereby increasing its salt concentration. The increased salt concentration increases the surface water's density, causing it to sink. This in turn causes the upwelling of cooler waters that are then warmed by the sun, and the cycle continues. Forces linked to the Earth's rotation also govern the direction of currents. These Coriolis forces cause ocean currents to move clockwise in the Northern Hemisphere, and counterclockwise in the Southern Hemisphere.
http://www.aquatic.uoguelph.ca/oceans/ArticOceanWeb/Currents/frontpagecur.htm