Ricerc@Sapienza

Images of the giant planets Jupiter and Saturn show highly turbulent storms and swirling Q23
clouds that reflect the intensity of turbulence in their atmospheres. Quantifying planetary turbulence is
inaccessible to conventional tools, however, since they require large quantities of spatially and temporally
resolved data. Here we show, using experiments, observations, and simulations, that potential vorticity
(PV) is a straightforward and universal diagnostic that can be used to estimate turbulent energy transfer in

A series of experiments with rotating, electromagnetically forced, turbulent flows were carried out at the Sapienza University of Rome to investigate the eddy-wave duality in flows with a β-effect and the electromagnetic force acting in the westward direction. When the β-effect is significant, i.e., as in planetary atmospheric and oceanic circulations, nonlinear eddy/wave interactions facilitate flow self-organization into zonal patterns in which Rossby waves and westward propagating cyclonic and anticyclonic eddies coexist.