The correct option is 1 and 3 only.
Explanation
The Inter Tropical Convergence Zone (ITCZ) is a broad trough of low pressure located in equatorial latitudes. It plays a central role in the general circulation of the atmosphere and is the rising limb of the Hadley Cell.
Statement-wise Analysis:
- Statement 1 is Correct: The ITCZ is a thermally induced low-pressure zone. Due to high insolation at the equator, the air heats up, expands, and rises, creating a region of low atmospheric pressure.
- Statement 2 is Incorrect: As the name implies, the ITCZ is a zone of convergence, not divergence. The Northeast Trade Winds and the Southeast Trade Winds flow towards the equator and converge in this zone. Divergence of winds typically occurs at the Subtropical High-Pressure Belts (around 30° N and S).
- Statement 3 is Correct: The air that converges at the ITCZ rises due to convection. Upon reaching the top of the troposphere (approximately 14 km altitude), it moves horizontally towards the poles. This accumulation of air eventually descends at the subtropical latitudes, completing the Hadley Cell circulation.
Key Takeaway:
The ITCZ is defined by low pressure, the convergence of trade winds, and the vertical ascent of warm air, which drives the global atmospheric circulation towards the poles.