Website of Mariann Darányi

VASVÁR, 2009-10-02-06
Krakkow, Katowice, 2006
Department of Meteorology, ELTE


Marine stratocumulus clouds frequently form parallel rows, 
or “cloud streets,” along the 
direction of wind flow. When the flow is interrupted by an obstacle 
such as an island, a series of organized eddies can appear within 
the cloud layer downwind of the obstacle. 
These turbulence patterns are known as von Karman vortex streets. 
In these images from NASA’s Multi-angle Imaging SpectroRadiometer, 
an impressive vortex pattern continues for 
over 300 km southward of Jan Mayen island. Jan Mayen is an isolated 
territory of Norway, located about 650 km northeast of Iceland in the 
north Atlantic Ocean. Jan Mayen’s 
Beerenberg volcano rises about 2.2 km above the ocean surface, 
providing a significant impediment to wind flow.

Fluid dynamicist Theodore von Karman was the first to derive the conditions under which these turbulence patterns occur. Von Karman was a professor of aeronautics at the California Institute of Technology and one of the principal founders of NASA’s Jet Propulsion Laboratory.