RAS question
The ITCZ in January is located approximately where?
Correct answer: (D) South of the equator (around 15°-20°S).
In January, the Inter Tropical Convergence Zone lies south of the equator, roughly around 15°-20°S.
Explanation
The Inter Tropical Convergence Zone is the low-pressure belt where trade winds converge and air tends to rise. NCERT explains that its position shifts seasonally: in July, heating over the subcontinent pulls it northwards to about 20°N-25°N over the Gangetic plain, while in winter the ITCZ moves southward. January is Northern Hemisphere winter, so the zone follows the apparent movement of the sun into the Southern Hemisphere. That places it roughly around 15°-20°S, over belts such as northern Australia, southern Africa and South America. This seasonal displacement also explains why the Indian landmass is not the ITCZ's January position.
Why the other options are wrong
- (A) The equator is the basic reference position of the ITCZ, but in January it has shifted southward into the Southern Hemisphere.
- (B) Around 25°N over India is the July monsoon-season position, not the January winter position.
- (C) Around 30°N corresponds to the subtropical high belt, whereas the ITCZ is a low-pressure convergence zone that shifts south in winter.
Concept
This tests the seasonal migration of pressure belts and its link with the Indian monsoon mechanism. RAS repeatedly uses this concept because it connects global circulation with India's January and July wind patterns.