Why did the sky turn red during California’s wildfires?

It’s all because of two phenomena: scattering and absorption of light

A runner takes a picture of the Bay Bridge in San Francisco under smoke-clogged skies. (Photo: Philip Pacheco, Getty Images)

But doesn’t scattering cause the sky to be blue? Yes that is true, but we are talking about two different types of scattering. Scattering of light by atmospheric molecules is quite different from scattering of light by smoke particles as we will see. But…