Atmospheric tracers and the study of the general circulation of the atmosphere

The properties of atmospheric tracers, mostly trace substances like water vapour, ozone, radioactive matter, are discussed in general and in particular. Some of the broad features of the general circulation and its mechanisms are then described to provide a background to the knowledge on atmospheric tracers which has been increasingly accumulated in recent years and which is here reported. Its implications are discussed in relation to the circulations in the troposphere and stratosphere and to transfer between these domains.