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Difference between revisions of "Inter Tropical Convergence Zone (ITCZ)"
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Aircraft flying through the ITCZ will encounter all the hazards associated with Cb clouds such as icing, turbulence, lightning, and wind shear. For further information see the
Aircraft flying through the ITCZ will encounter all the hazards associated with Cb clouds such as icing, turbulence, lightning, and wind shear. For further information see the article [[Cumulonimbus]].
Revision as of 07:38, 2 June 2009
Inter Tropical Convergence Zone
The Inter Tropical Convergence Zone, or Inter Tropical Convergence Zone (ITCZ), is the belt of low pressure girdling the Earth, near the equator, where the trade winds of the Northern and Southern Hemispheres come together. It is formed by the vertical ascent of warm, moist air from the latitudes above and below the equator. As the air ascends it cools, releasing the accumulated moisture in an almost perpetual series of thunderstorms.
The position of the ITCZ varies with the seasons. In July, over the Atlantic and Pacific, the ITCZ is between 5 and 15 degrees north of the Equator, but further north over the land masses of Africa and Asia. In January, over the Atlantic, the ITCZ sits no further south than the Equator, but extends much further south over South America, Southern Africa, and towards Australia. Over land, the ITCZ tends to follow the sun's zenith point.
Where the trade winds are weak, the ITCZ is characterised by isolated Cumulus and Cumulonimbus (Cb) (Cb) cells. However, where the trade winds are stronger, the ITCZ can be a solid line of active Cb cells embedded with other cloud types developing as a result of instability at higher levels. Cb tops can reach as high as 55,000 feet, and the ITCZ can be as wide as 300 nautical miles in places presenting a formidable obstacle to aircraft.
Aircraft flying through the ITCZ will encounter all the hazards associated with Cb clouds such as icing, turbulence, lightning, and wind shear. However, it is in this zone where the most severe effects may often be encountered. For further information see the article Cumulonimbus (Cb).