Tundra Double Rainbow

Provided and copyright by: Koushik Dutta, Institute of Physics, Bhubaneswar, India
Summary author: Koushik Dutta 

The photo above showing a classic double rainbow was taken near Healy, Alaska, on May 27, 2004. Following a light rain shower, this beautiful primary rainbow and a prominent secondary rainbow appeared at about 10:30 p.m. (local time). It was snapped during a field sampling session by scientists from the Department of Botany at the University of Florida. Despite atmospheric temperatures that are too cold, for most of the year, to permit liquid precipitation to fall, rainbows can be observed at polar latitudes. In fact, since rainbows can only be observed when the Sun is less than 43 degrees above the horizon, and since the Sun is never much higher than this north of the Arctic Circle, rainbows are not as rare as you might think at high latitudes during the brief summer. See the Earth Science Picture of the Day for January 2, 2008.

In the foreground, tundra soils covered with sphagnum moss are seen. Carbon dioxide stored beneath these soils may gradually be released if air temperatures continue to climb, causing further warming in the Arctic.