|MadSci Network: Earth Sciences|
The oceans, as with most energy driven forces on this planet, are driven mainly the Sun. As the ocean revolves around the sun on it's axis, different parts of the planet are heated at different rates. In general, the tropics get the most sunlight and the poles get the least. The energy differential is dissipated through convective currents that move both on the surface and in the deep waters. Another factor contributing to ocean currents include the deposit of river freshwaters into the oceans. The mixing of freshwater into a certain ocean area may cause saline waters to sink. This kind of mixing drives some of the peculiar deep water ocean currents behavior. There is much that is not known about the ocean currents. Ocean currents are a major factor in everything from global warming to periodic weather events such as El Nino.
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