The Indian Ocean Experiment: Widespread air pollution from South and Southeast Asia

The Indian Ocean Experiment (INDOEX) was an international, multiplatform fi eld campaign to measure Long-range transport of air pollution from South an d Southeast Asia toward the Indian Ocean during the dry monsoon season in J anuary to March 1999. Surprisingly high pollution Levels were observed over the entire northern Indian Ocean toward the Intertropical Convergence Zone at about 6 degreesS. We show that agricultural burning and especially biof uel use enhance carbon monoxide concentrations. Fossil fuel combustion and biomass burning cause a high aerosol Loading. The growing pollution in this region gives rise to extensive air quality degradation with Local, regiona l, and global implications, including a reduction of the oxidizing power of the atmosphere.