Cap Cloud Over Mt. Blanc, France
September 06, 2011
Photographer: Piero Armando
Summary Author: Piero Armando; Jim Foster
These two photos show views of a cap cloud observed over Mt. Blanc, France at different times on the same day. The top photo was taken at 9:10 a.m. and the bottom photo was captured nine hours later at 6:15 p.m. Mount Blanc at 15,782 ft (4,810 m) is the highest peak in the Alps and in fact the tallest mountain in Western Europe. The wind direction here is from left to right (west to east). Cap clouds are more or less stationary clouds that form when moist air, forced up mountain summits, cools and condenses. Note how little the cloud pattern has changed during the course of the day. Photos taken on July 2, 2011 from Lillaz village (Aosta Valley), Italy.
Photo details: (for both photos): Canon EOS 30D camera; 225mm focal length; Aperture: f/9 aperture; Exposure Time: 1/800 sec. exposure time; 100 ISO.