Abstract :
There has been very little new data on the atmosphere of Venus in recent years, but ongoing studies of data from space missions such as Pioneer Venus, Venera and Galileo, plus ground-based observations, have uncovered, but not yet resolved, a number of fundamental questions relating to the atmospheric global circulation. In addition to the perennial problem of trying to understand the forces driving the equatorial super-rotation, there is still no reliable model, even in the qualitative sense, of the mean meridional (equator-to-pole) circulation, nor of the peculiar giant polar vortices which are a major feature of it. There is pronounced meteorological activity in the upper troposphere, the general character of which, let alone the processes responsible, remains unknown. The very limited observations of temperature and compositional trends, wave motions and cloud features which exist at present provide some clues as to what may be happening on the Earthʹs twin planet and suggest the next steps towards a more detailed, quantitative understanding.
