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APPARATUS

This is a rotating tub of water with a beaker of ice at its center.  Radial convection currents are deflected by the Coriolis effect and form eddies.  The flow patterns are made visible with drops of food coloring and are displayed on the screen by a wireless camera rotating with the turntable.  The eddies resemble the large scale circulation patterns in the earth's atmosphere in the middle latitudes, driven by the radial temperature gradient and the earth's rotation (see http://www.meteo.psu.edu/~gadomski/SAT_NHEM/atlanim16wv.html).

Start with the empty weighted beaker at the center, and set the turntable to rotate at 16 rpm.  Let it run for a few minutes until the water is spinning as one.  Put ice and water in the center beaker and wait a minute or so for the convection currents to be established.  Place a couple of drops of red dye at the perimeter and green dye near the ice.  The screen shot above was taken seven minutes after the dye was introduced.

NOTES
 

The turntable turns clockwise.

REFERENCE

Weather in a Tank:  http://paoc.mit.edu/labguide/apparatus.html