why temperature decreases progessively from equator towards the poles and why it is zero in polar areas and higher in high altitudes?

at equator, the sun rays fall perpendicular which results into the maximum amount of heat and ligth in that area, but as we move towards the pole so the surface becomes more slanted or curved  due to which the sunrays and the ligth amount is less there. this is the reason or decrease in the temprature.

the sun rays which come to the surface of the earth are absorbed and radiated back by the earths surface, the effect of this heat radiation is maximum at the ground level and minimum at the altitudes. the heat radiations fail to be effective at the heights.