What effect does solar radiation have on climate when comparing the equator to polar-regions?

The solar radiation is one of the main factors that shapes the climate all over the globe, so the climate differs with the less or more solar radiation it gets. The polar regions are cold, this is due to the fact that the solar radiation in here is very obscure, because the solar radiation falls at a very wide angle the heat is dispersed over larger area, thus the land gets very little warmth. The Equator, on the other hand, gets direct solar radiation, the sun light falls at a 90 degrees angle or close to it, so the radiation is more concentrated on a smaller area, thus the warming is bigger.