Colored rain has been falling on the planet for centuries, and it can occur in a variety of hues — from reds and yellows to blacks and milky whites. In fact, in 2001, there were reports of scarlet, green, yellow, brown and black rains in southern India. While scientists determined that airborne spores from algae caused these rains, a variety of substances can create strange-colored rain.
In Europe, red rains are typically dyed by dust carried from Saharan sandstorms. Pollen can contribute to yellow rain, and dusts from coal mines have been known to cause black rain.