252.Weather

VAN GOGH CLOUDS | in Mutare, Zimbabwe.

2016-03-13 // 0 Comments

Sunday, Mar. 13, 2016 Peter Lowenstein lives in Mutare, Zimbabwe. For a few minutes last Friday, he felt as if he were transported from Africa into a painting by Vincent van Gogh. "Just before sunset," says Lowenstein, "a thin band of wavy clouds developed above a cumulonimbus anvil and became iridescent." He snapped [the above picture]. These clouds, sometimes called "billow clouds," are produced by the Kelvin-Helmholtz instability when horizontal layers of air brush by one another at different velocities. It is widely believed that these waves in the sky inspired the swirls in van Gogh's masterpiece The Starry Night. The delicate pastel colors of the waves come from irridescence--the diffraction of sunlight by tiny water droplets in the clouds. As the sun set, the colors faded to gray, returning Lowenstein to his porch in Zimbabwe. [...]