Atmospheric processes involved in the stratospheric ozone problem

It is pointed out that during the past decade, a decrease in the ozone layer and an increase in the carbon dioxide content of the atmosphere have jointed urban smog as major threats to the atmospheric environment. An outline is provided of the present state of knowledge about the atmosphere relating to the ozone problem, and the nature of major uncertainties are indicated. A temperature profile of the atmosphere is considered along with details regarding the stratospheric chemistry, atmospheric models, predictions of ozone depletion by halocarbons, comparisons between one-dimensional models and atmosheric measurements, model predictions for halocarbon releases, and two-dimensional model results. Atention is also given to estimates of uncertainties in model predictions, feedbacks and interactions with other pollutants, postozone trends as a possible early warning system, and other possible threats to the O3 layer.