ITCZ

1. ITCZ ITCZ

2. Global Air Circulation The ITCZ, is the region that circles the Earth, near the equator, where the trade winds of the Northern and Southern Hemispheres come together. The intense sun and warm water of the equator heats the air in the ITCZ, raising its humidity and causing it to rise. Creating a band of low pressure. Variation in the location of the ITCZ drastically affects rainfall in many equatorial nations, resulting in the wet and dry seasons of the tropics rather than the cold and warm seasons of higher latitudes.

3. The ITCZ • The ITCZ will move North during the summer in the Northern Hemisphere reaching its furthest point North in July. • It then moves South during summer in the southern hemisphere reaching its furthest point South in January.

4. Rainfall at the ITCZ • The trade winds will converge at the ITCZ.

5. Rainfall at the ITCZ • Where winds converge, moist air is forced upward. This causes water vapour to condense, or be "squeezed" out, as the air cools and rises, resulting in a band of heavy precipitation around the globe

6. The influence of cT and mT

7. The impact of the ITCZ on the West Coast of Africa • In summer the ITCZ moves North bringing rain to the Northern parts of Western Africa. In January the ITCZ has moved South bringing hot dry weather to the North of Western Africa. • The ITCZ is a band of low pressure associated with rainfall as two air masses meet and force air upwards creating a band of heavy cloud.

8. THE ITCZ 2005 Q1 • Kano has a distinct _____ season from ______ to __________ with the highest rainfall of ________mm in July. This is caused by the movement of the ITCZ north during summer in the ____________ ______________. • The ITCZ is a band of _________pressure or a zone of ___________ which is associated with a band of _______________. In July the ITCZ id directly over Kano hence the peak rainfall. As the ITCZ moves further North is allows _________ __________ air to reach further into Northern Nigeria again this brings with it warm, moist air and rainfall. As a result for 6 months of the year Northern Nigeria experiences a ___________season. As the ITCZ moves South for the remaining 6 months the North of Nigeria is affected by the_______ ___________ air mass bringing _________and _________ weather to much of the area, • Enugu has rainfall throughout the year with two distinct peaks in _________ and _______________. Again these peak rainfall moths are when the ITCZ is directly overhead bringing a band of low pressure and heavy rainfall. Enugu is influences by the __________ __________ air mass throughout the year with lowest rainfall in ____________ and ______________when the ITCZ will be slightly South of Enugu allowing ________________ _____________ air to influence the rainfall.

9. Sample answer • Kano has a distinct wet season from May to September with the highest rainfall of 250mm in July. This is caused by the movement of the ITCZ north during summer in the Northern Hemisphere. The ITCZ is a band of low pressure or a zone of convergence which is associated with a band of precipitation. In July the ITCZ id directly over Kano hence the peak rainfall. As the ITCZ moves further North is allows mT air to reach further into western Africa again this brings with it warm, moist air and rainfall. As a result for 6 months of the year Northern Nigeria experiences a wet season. As the ITCZ moves South for the remaining 6 months the North of Nigeria is affected by c T air mass bringing hot and dry weather to much of the area, • Enugu has rainfall throughout the year with two distinct peaks in May and September. Again these peak rainfall moths are when the ITCZ is directly overhead bringing a band of low pressure and heavy rainfall. Enugu is influences by the mT air mass throughout the year with lowest rainfall in January and December when the ITCZ will be slightly South of Enugu allowing Ct air to influence the rainfall.