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Wednesday, September 5, 2007

Weather: Down-to-Earth Rainbow

Click image for an enlargement.

On my walk around the village yesterday, I observed an atmospheric phenomenon I can't recall having ever seen before. The sky was partly cloudy, with fog and mist in certain locations. Looking to the northeast, in the direction of the town of Diesse, a forested hillside in the distance was painted with the colours of the rainbow. No rainbow was apparent in the sky, and there was no observable curvature of the visible segment. I originally thought of calling this a “fogbow”, but that is an entirely different phenomenon—the fact that colour was apparent means that the water droplets must have been larger than those in fog, but it didn't appear to be raining in that vicinity, so I thought of calling it a “mist-bow” (even though it doesn't bow), but doggone if Minnaert's The Nature of Light and Colour in the Open Air doesn't use that word for something else! So, I guess I'll leave it unnamed for now. Named or not, it was a very pretty effect.

Posted at September 5, 2007 14:59