Asperitas Clouds Over the Canary Islands

January 08, 2018

Asperitas sobre pici viejo 26 nov 17 -1-2 (1)

Photographer: Roberto Porto
Summary Authors: Roberto Porto; Jim Foster

Shown above is fantastical sky that looks like it could have been painted by a post-impressionist artist. I captured this photo in Teide National Park, on the Canary Island of Tenerife (Spain), during the afternoon of November 26, 2017. Previously classified as asperatus, asperitas clouds form under similar atmospheric conditions that produce mammatus clouds -- air cooled by the sublimation of ice crystals punching through an existing cloud base. However, with asperitas, strong wind shear at the cloud level causes the clouds to shape into wave-like structures called undulatus. They're not often seen, but when they are, they're always captivating.