Oceanic circulation would be the main engine of the asymmetry in the regimes of Rain tropical. It rains more in the north than in the south of the equator, however, the hemisphere on is more exposed to solar radiation, and therefore with a higher rate of increase in the humidity.
This observation has always been a mystery, but today an American research team shows that it can be attributed to the circulation sundial oceanic.
Under the tropics, it rains more in the north than in the south. Precipitation at the equator is modulated by the zone of convergence intertropical. It is an atmospheric band of several hundred kilometers, formed by the convergence of masses of a government-protected hot and wet, pushed by the trade winds.
This cloud belt constitutes the frame upward of Hadley cells, which distribute on one side and the other of the Ecuador the surplus of accumulated energy. However, this area of convergence tropical It is not exactly at the equator, but at 5º N. Its position causes a asymmetry in rain regimes whose reason was unknown for a long time.
Scientists have long attributed this difference in rain tropical to the geometry of the oceans. The asymmetry precipitation would be related to the asymmetry of the temperature of the oceans, in turn related to the asymmetry of the costas continental.
Actually, it appears that the circulation thermohaline it is the main mechanism that causes this asymmetry.
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