Climatology-I

Md. Hanif Bhuian

Dept. Of Geography & Environment

Jagannath University

Dhaka, Bangladesh

Topics: Tropical Circulation

Presentation On

All of activity of Tropical

Circulation become in Tropical zone.

Tropical Circulation

What is Tropical zone ?

Tropical Zone

30N & 30S

Latitude is area of

Tropical Zone.

Equatorial or tropical

front Introtopical

convergence(ITCZ)

Region of ITCZ North Introtopical

Convergence (NITC)

Region of N.E. Trade

wind (blow from N sub-

tropical HP to NITC.

South Introtopical

Convergence(SITC)

Region of S.E. Trade

wind(blow from S sub-

tropical HP to SITC.

Characteristics of Tropical Zone

A)Doldrum(ITCZ)

B)Equatorial Westerlies

C)Trade Wind

Doldrum(ITCZ)Trough– Belt of Equatorial

low pressure( 5N to 5S)

This Trough is Doldrum.

Variation

northward(NITC) – summer solstices.

-- 21june

southward(SITC) –winter solstices.

-- 22Dec

Northward (NITC)—summer solstices

sun in vertical(north part)

over the tropic of cancer

21June

Southward (SITC)—winter solstices

sun in vertical (south part)

over the tropic of Capricorn.

22 Dec

3 Zones of Doldrum(based on Crowe)

Indo-pacific doldrum(eastern coast of Africa.

Equatorial western (coastal region of Africa).

Western coastal(region of central America) .

Equatorial Westerlies

Wind flow westerly (West to East).

South-Western monsoon(based on Fohn)

South-Western Monsoon

South-Western Monsoon

30-35N latitude over the Indian ocean.

Trade Wind

Wind flow from sub-

tropical HP to Equatorial

low pressure belt(ITC)

Direction

N.E. direction

-- Northern hemisphere(NITC).

S.E. direction

-- Southern hemisphere(SITC).

Trade wind help

Sea merchants for sailing their ships

Deflection of Trade wind

Freels Law – Based on

carioles force rotation of the

Earth.

Trade wind deflected–

Right in the northern

hemisphere

Left in the southern

hemisphere

Weather Condition of Trade wind

Polar part or Eastern

site – sub-tropical

anticyclone are Dry.

Because of,

Strong atmospheric

stability

Strong inversion of

temperature

Clear sky

Equator part of Trade wind

Equator part

Humid

Because of,

atmospheric

instability

much precipitation

Hadley Cell

The Trade wind zone(NITC & SITC) is Hadley cell.

(basis of convective model prepared by Hadley)

Thanks to all of you…