Wind currents from Asia and India can carry ozone smog and pollution thousands of miles away to the southern Atlantic Ocean.
During certain seasons researchers believe the build-up of ozone smog is caused by pollutants being carried on a train track of air current from the Indian Ocean.
NASA satellites and weather balloons are tracking wind currents, fires and lightning strikes to identify large areas of ozone smog.
Scientists using NASA's Total Ozone Mapping Spectrometer satellite instrument also identified areas of ozone smog moving high over Africa.
By monitoring the flow of pollutants, NASA seeks to develop scientific understanding of how Earth copes with natural and man-made hazards.