Long-lived eddies in the laboratory and in the atmospheres of Jupiter and Saturn

Abstract

The Great Red Spot (GRS), the three White Ovals, and other long-lived anticyclonic eddies in Jupiter's atmosphere might be dynamically similar1 to the closed, stable baroclinic eddies that were first discovered in laboratory studies of thermal convection in a rotating fluid subject to internal heating and sidewall cooling2,3. We outline here results of new laboratory and numerical experiments on the structure, energetics and stability of such eddies, which strongly support the suggestion that these laboratory and atmospheric flows (including similar eddies found on Saturn4) might all be manifestations of the same dynamical process—‘sloping’ or ‘slantwise’ convection. Included in our numerical experiments are cases with internal cooling and sidewall heating, in which stable baroclinic eddies with a cyclonic peripheral jet stream at upper levels surrounding a region of slow descent have been produced and studied. We suggest that these cyclonic eddies are dynamically similar to the ‘barges’ observed in Jupiter's Tropical and Temperate Belts5.