Pre-Voyager velocities, accelerations and shrinkage rates of jovian cloud features

The Voyager 1 data yield detailed information on the latitudinal dependence of velocities in the jovian atmosphere. This enhances the possibility of interpreting the time-dependent behaviour of long-lived jovian cloud features. This article summarises pre-Voyager velocity data, stressing gross differences with the Voyager 1 results. Analytic expressions are given for average drift rates and shrinkage rates for the Great Red Spot and white ovals (located at -23° and -34° latitude, respectively) from 1943 to 1979.