New evidence for ozone depletion in the upper stratosphere

Abstract

Differential absorption lidar measurements at the Meteorological Observatory Hohenpeißenberg between 1987 and 1993 show a statistically significant ozone decrease between 32 and 42 km, peaking at about −1.7% per year at 39 km altitude. This depletion is higher than reported by SAGE II or SBUV, yet the Hohenpeißenberg data agree very well with the results from Umkehr measurements. The observed ozone trend is in the upper range of predictions from photochemical models (−0.5 to −1.5% per year), whereas SBUV and SAGE II results are close to the lower end of the simulations. The agreement with photochemical models indicates that the depletion is most likely caused by catalytic ozone destruction through anthropogenic chlorine.