Internal-tropical Konvergenzzone

internal-tropical or inter+tropical Konvergenzzone (ITC for I of nter T ropic C onversion or ITCZ for I of nter T ropical C onvergence Z one) is a few hundred kilometers broad low pressure gutter into near-equator ones in the range from the north and the south of the one on the other appropriate Trade winds. It is characterized by convection features and a usually strong heavy cloudiness.

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Die Innertropische Konvergenzzone
the internal-tropical Konvergenzzone
Entstehung des Tropenklimas
emergence of the tropical climate

in the proximity of the equator becomes airby the there strong sun exposure strongly heats up, whereupon these drop expanded and in the consequence the values both for the atmospheric pressure and for the air pressure at the soil strongly. Thus the entire globe re-clamping , stable Tiefdruckgebiet of very large extent forms, both vertically and horizontal, which represents a low pressure gutter due to its hose-like training. In such a way warmed up and expanding air konvektiert (thermal advection, vertically) in the consequence and must carry here work out, why it cools down with increasing height (joule Thomson effect). With falling below the dew pointform due to the water vapour capacity of air , in the group with in their contained usually high air humidity, sinking thereby, high-reaching and substantial cloud formations. These lead to strong precipitation (the Zenitalregen in such a way specified) and cause a usually tropical or subtropical climate.Since it is a thermodynamic regularity the fact that from mass flows and result with the convection of air at the soil no vacuum can adjust itself air pressure differences follows at the soil horizontal air, which one calls convergence. This mass flow, here wind mentioned, is toward and strengthrelatively constantly. He is diverted to the right and in the Southern Hemisphere in direction of motion to the left by the Corioliskraft , a fictitious force, on the Northern Hemisphere in direction of motion, why the resulting hoist, which trade winds, an east component possess.

change and consequences

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Yearly variation

the internal-tropical Konvergenzzone varies with the seasons and follows here the zenith conditions of the sun, which depends again on the angle of the Erdachse for the level of the ecliptic, with a delay of approximately one month. There the sun exposure (see also solar power) here due to usuallyhigh angle of incidence the comparatively largest Strahlungstromdichte exhibits, depends also the thermal effect on the zenith conditions and to it the equator only partially to the ITC identical.

In the summer of the north hemisphere the ITC is northward, shifted in the winter to the south therefore. Their situation becomes additionalvery strongly over the continents, there air over these modifies itself more strongly and/or. faster warms up than over the oceanic water surface. The size of the land mass affects accordingly the process of the ITC and thus also the climatic zoning. Without “disturbing” land masses the zoning of the climate zones becameclearly more strongly resemble a global belt sample. The deviation of the ITC from the equator over South America and Asia is particularly strong. The very large north south deviation between the seasons in Asia favours here the training of Monsunen. By strong convection the tropopause lies in the ITCmore highly.


the storms of the internal-tropical Konvergenzzone in the east Pacific.
Cumulonimbus cloud

the consequences of ascending air are here strong Wolkenbildung (Cumulonimbus), cloud-break-like showers and thunderstorms. This lies in the fact justified that those cools all right damp air down when ascending slowly and as consequence thoseWater vapour capacity the same sinks. The relative air humidity continues to increase thereby always. If the dew point is fallen below, then it comes as consequence quite fast to the condensation, which brings enormous quantities out of liquid water due to the extents of the convection current and so also humid climates favoured.

By the ITC are at the turning circles large deserts developed. This is connected with the fact that the dry air, which descends at the turning circles again exhibits a large Sättigungsdefizit (is steam hungry “) and thus the evaporation strongly favours. If the ITC at the turning circles stands, no humidity can ascend andtherefore also no precipitation develops. The conditions of the ITC are connected also with the zero winds Kalmen.

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