These Bizarre Cloud Patterns are von Kármán’s Vortices, Caused by the air Wrapping Around Tall Islands

Three peaks in Cape Verde form von Kármán vortex streets when wind conditions are right. Image Credit: Lauren Dauphin, using MODIS data from NASA EOSDIS/LANCE and GIBS/Worldview.

This is an image of some of the islands that make up the nation of Cape Verde. While most in that group of ten islands are flat, some are very tall: Fogo, Santa Antão, and São Nicolau. Those three stand well above their compatriots, with Fogo reaching an altitude of 2,829 metres (9,281 feet).

The three tall volcanic islands sometimes interact with the wind to create von Kármán vortices, also called von Kármán vortex streets.

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Astronomy Cast Ep. 516: Polar Vortices

It’s cold right now. Okay, fine, here on Vancouver Island, it’s actually pretty warm. But for the rest of Canada and big parts of the US, it’s terrifyingly cold. Colder than Mars or the North Pole cold. This is all thanks to the break up of the polar vortex. What are polar vertices, how do they form, and where else to we find them in the Solar System?

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