Observations and Interpretation of Changes in Stratospheric Ozone Following the Pinatubo Eruption

Following the eruption ofMt. Pinatubo, substantial decreases were observed both in ozonesonde and total column ozone observations. These decreases are illustrated with data from mid-latitudes and polar regions, and are interpreted in terms of heterogeneous chemical processes, both involving hydrolysis of dinitrogen pentoxide and reactions involving chlorine species such as ClONO₂ HOCl, and HCl on sulfate aerosols. In addition, this paper shows in detail for the first time how the ozone budget varies with altitude in response to sulfate aerosol perturbations, revealing the reasons for observed increases in ozone above about 25 km following the eruption.