Von Karman vortices forming in the stratocumulus field downwind from the volcanic island of Rishiri-to in the northern Sea of Japan off the northwest coast of Hokkaido, Japan, in April 2001. These features form when a stable atmosphere with low clouds flows past a relatively small obstacle with a height greater than the depth of the cloud layer. (Courtesy of NASA, Space Shuttle Mission Imagery, STS100-710-182)