Eli5 Why does the “directness” of sunlight change its heating effect

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Bill nye says our change in seasons is largely due to the fact that the directness of the sunlight hitting a given place changes due to the earths tilt and position in its orbit.

Why does the directness of light create more heat (hitting at equator for example), while glancing light rays (hitting antarctica) produce less heat?

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This is called the projection effect, and can be demonstrated by shining a flashlight directly onto a surface, then tilting it. The same light gets spread over a much larger area. So you might have say 1 watt per 1 square centimeter vs 1 watt per 4 square centimeters. The light source didnt change intensity at any point, just the directness. (you should also keep the flashlight at basically equal distance from bulb to paper, the real difference in distance is trivial.)

Another major reason is the atmosphere and the fact that it absorbs/redirects radiation as well.

Light hitting Antarctica travels through much more atmosphere. Draw two circles, one just a bit bigger than the other. Starting at the edge of your paper, draw two lines (originating from the same spot), one to the closest point on the inner circle, and the other to the furthest edge you can reach in a straight line, and observe how far that line travels through the outer circle.

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