ITCZ
ITCZ
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.
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.
Rainfall at the ITCZ
• The trade winds will
converge at the ITCZ.
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
The influence of cT and mT
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.
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.
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.