What is the main reason for geographic zoning?

The main reason for the geographic zoning of the planet’s surface is its spherical shape, since in this way only the central part (close to the equator) is at right angles to the Sun and receives a lot of energy from it for a whole year. In other zones, as the distance from the equator increases, the angle of incidence of the rays also increases, and part of the solar energy is screened back into space. In the zones close to the poles, the rays almost do not hit the surface of the planet, but slide through the atmosphere, and so the Earth receives little energy.