Albedo in Brooklyn

The backyard light was on the other night and the light bounced back brightly into my apartment because of all the snow. Ah, I thought, albedo in action.

Technically, albedo is a “ratio of reflected radiation from the surface to incident radiation upon it” (Wikipedia). Crossword fiends and Catholics will recognize the alb in the word, from the Latin for white. The polar ice caps reflect a greater amount of the radiation hitting them than does ice-free terrain. Put another way, you shouldn’t drive a black car in the desert.

Less ice = less albedo, which means more heat which means less ice, which means less albedo and so on. This is one of the feedback mechanisms of a warming world.

I quickly turned out the light.
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