Tropospheric ozone from satellite total ozone measurements

A method for determining the amount of ozone in the tropical troposphere from concurrent sets of satellite data is presented. This procedure is applied only in the Tropics and the results indicate that a significant longitudinal gradient is present at low latitudes and that the highest amounts of tropospheric ozone are located west (i.e., downwind) of Africa and South America. Such a distribution suggests that biomass burning, or another stationary source of continental origin, is the largest source of ozone in the Tropics. The integrated amount of ozone in the Tropics that is derived from this analysis is comparable to or only slightly less than the amount of ozone that is present in northern mid latitudes. If such an interpretation is valid, then it suggests that the magnitude of the amount of tropospheric ozone resulting from in situ photochemical production in this region is comparable to the in situ photochemical source from industrialized emissions.