The most common atmospheric effect, the blue sky, is caused by scattering. The light from the sun is white, and most coloured scattering phenomena are caused by preferential scattering of the colours that make up white light. In the case of the blue sky, the short wavelength blue light is more likely to be scattered by the very small particle and irregularities in the atmosphere. Also other atmospheric effects such as those caused by shadows are only visible because the edge of the shadow is visible because of scattering in the atmosphere.
Blue Skies and Red Sunsets We see the blue sky nearly every day (or we should). I bet most of us take it for granted. But why is the sky blue, and why are sunsets often red.
Cloud Colour Most people think white when it comes to the colour of clouds. Pushed a bit we would all realise that clouds come in all types of colurs. But why?
Blue Mountains In Australia this phenomena can be so pronounced that a region of mountains outside Sydney is called The Blue Mountains.
Whiteout Flat white light causing a lack of definition. This condition can be caused by uniform cloud cover over snow, or blowing snow.