as the sun goes around, the light, and the pressure of the light, [for everything has pressure], fans the small amount of heat which is rising from the earth, and accelerates it [the heat], making it hotter in the air and our skin, etc. this is physically proven by the sun when it is in the arctic circle and it still isn't warm like around the equator, because ice [water] has no pores for heat to rise through, whereas around the equator, heat rises through sand and porous earth ! the little heat that rises around the arctic circle is because of the land underneath the ice. it is now melting and soon it will be much warmer that when there was ice BECAUSE OF THE LAND !