Vortices are common features in fluid flows, They have important implications for the flight of airplanes where they are generated by boundary layer processes. Wing tip vortices are a limiting factor for the frequency with which airplanes can take off.
An example of a much larger scale vortex is a hurricane. Flow at these scales is strongly affected by the earth's rotation: the flow around a hurricane is counterclockwise in the northern hemisphere and clockwise in the southern hemisphere.
Hurricane Isabel
Cessna Downwash
Student making vortices in a rotating tank at the Fluid's lab
