In the Northern Hemisphere, for example, predictable winds called trade winds blow from east to west just above the equator. The winds pull surface water with them, creating currents. As these currents flow westward, the Coriolis effect—a force that results from the rotation of the Earth—deflects them. The currents then bend to the right, heading north. At about 30 degrees north latitude, a different set of winds, the westerlies, push the currents back to the east, producing a closed clockwise loop.
Hope that helped :D
The reason for language diversion is the isolation of the people who speak the same language, but due to diversion and lesser contact between these people, now the language is used only in the dialects.
