Meridional distribution of ozone in the troposphere and its seasonal variations

Data from 5 years of continuous surface ozone measurements made at 16 European and African stations, located on a meridional chain between 69.5°N and 34°S, are presented. The analysis of monthly averages exhibits an annual sinusoidal variation with mean, amplitude, and phase characteristic for each latitude. Thirty-four meridional cross-sections of ozone in the high troposphere were measured aboard commercial jetliners. Both ground-based and aircraft measurements indicate enhanced stratospheric-tropospheric ozone injection at about 30°, 45°, and 65°N. The average ozone injection fluxes vary between 3×1010 mol/cm2 s at the equator and 10×1010 mol/cm2 s at the main injection latitude.