utc solar intensity due to proximity ratio between aphelion and perihelion axial tilt comparison still needed request confirmation of math there is some effect of the distance between the sun and the earth on the radiant energy reaching the earth there is some measure of heating northern latitudes up in their winter up to a maximum at jan and heating southern latitudes up in their summer thus the winters in northern latitudes all other variables such as warming by ocean currents etc removed from consideration are relatively more mild and the summers in southern latitudes variables removed relatively more extreme however the ratio of the aphelion furthest distance to the perihelion nearest is only so a difference of then to calculate what that does to the total radiant energy inverse square law says the radiation passing through any unit area is inversely proportional to the square of the distance from the point source received light quadruples as the distance halves so e sun energy stays the same so is solving for intensity i d is distance using perihelion distance as d aphelion and d multiply both sides of the equation by so that i is both multiplied and divided by the same number this cancels out and e is now e is now equal to i as i is no longer divided by anything i times aphelion intensity perihelion intensity times perihelion intensity aphelion intensity axial tilt total radiant energy and or comparison with the above remains to be found january