In a previous post, we looked at the effect of changing eccentricity on the total amount of solar energy intercepted by earth throughout a year. Now I’d like to take a look at how precession and obliquity (the tilt of the earth’s axis) affect the distribution of incoming sunlight. Neither of these factors affects the total energy intercepted by the entire planet earth throughout the year. But they have a profound effect on how that energy is geographically distributed.
This post has a lot of equations; if that makes your eyes glaze over you can skip past them and look directly at the graphs (and read some of the discussion) below.
