IDENTIFICATION OF WIDESPREAD POLLUTION IN THE SOUTHERN-HEMISPHERE DEDUCED FROM SATELLITE ANALYSES

Vertical profiles of ozone obtained from ozonesondes in Brazzaville, Congo (4-degrees-S, 15-degrees-E), and Ascension Island (8-degrees-S, 15-degrees-W) show that large quantities of tropospheric ozone are present over southern Africa and the adjacent eastern tropical South Atlantic Ocean. The origin of this pollution is widespread biomass burning in Africa. These measurements support satellite-derived tropospheric ozone data that demonstrate that ozone originating from this region is transported throughout most of the Southern Hemisphere. Seasonally high levels of carbon monoxide and methane observed at middle- and high-latitude stations in Africa, Australia, and Antarctica likely reflect the effects of this distant biomass burning. These data suggest that even the most remote regions on this planet may be significantly more polluted than previously believed.