Final answer:
The seasonal shift at the Intertropical Convergence Zone (ITCZ) is greatest between the Tropic of Cancer and the Tropic of Capricorn, regions close to the equator where Earth's tilt causes the most direct sunlight throughout the year.
Step-by-step explanation:
The seasonal shift at the Intertropical Convergence Zone (ITCZ) is greatest in the regions that are closest to the equator, specifically between the Tropic of Cancer and the Tropic of Capricorn. This area is where the Earth receives the most direct sunlight throughout the year due to the tilt of the Earth's axis at 23.5 degrees relative to its orbit around the Sun. During the solstices, these tropics mark the farthest points north or south that the Sun is directly overhead at noon. The seasonal variation in high latitude areas is more pronounced than in the tropics because the amount of direct sunlight received changes more drastically over the course of the year, impacting the climate significantly.