The status of investigations into anthropogenic effects on atmospheric ozone

Investigations that have been carried out on the spatiotemporal variability of the total content of ozone are surveyed. Particular attention is given to the existence of long-term trends. Results that have been obtained from numerical modeling of anthropogenic effects on ozone are analyzed, in particular the evaluations that have been made of the contributions from various components of the stratosphere and various chemical reactions. Also discussed are computational results illustrating the importance of having reliable data on reaction rates and of allowing for the interaction between radiative processes and photochemical processes and for the dynamics of the atmosphere. The chief result of anthropogenic activity is seen to be a redistribution of ozone with height rather than a change in the total amount of ozone. The absence of an additive effect in the contributions from the various components is considered significant.