Some takes on UV & cancer

: Part 1: In which I use my optical physics background to share some hopefully-uncontroversial observations Part 2: In which I boldly defy Public Health Orthodoxy on the whole UV situation Part 1: In which I use my optical physics background to share some hopefully-uncontroversial observations 1.1 UV depends a lot on “solar zenith angle” [a.k.a. “angle of the sun away from directly overhead”], not on how hot it is outside That means: you should mainly be thinking about UV exposure in proportion to how close it is to (1) the summer solstice and (2) solar noon. Here, I made this handy widget.