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

Lelieveld, J, Crutzen PJ, Ramanathan V, Andreae MO, Brenninkmeijer CAM, Campos T, Cass GR, Dickerson RR, Fischer H, de Gouw JA, Hansel A, Jefferson A, Kley D, de Laat ATJ, Lal S, Lawrence MG, Lobert JM, Mayol-Bracero OL, Mitra AP, Novakov T, Oltmans SJ, Prather KA, Reiner T, Rodhe H, Scheeren HA, Sikka D, Williams J.  2001.  The Indian Ocean Experiment: Widespread air pollution from South and Southeast Asia. Science. 291:1031-1036.

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aircraft measurements, carbonaceous aerosols, chemistry, chlorine emissions inventory, marine boundary-layer, optical-properties, particles, reactive chlorine, sulfur-dioxide, tropospheric ozone


The Indian Ocean Experiment (INDOEX) was an international, multiplatform field campaign to measure Long-range transport of air pollution from South and Southeast Asia toward the Indian Ocean during the dry monsoon season in January 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 biofuel 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, regional, and global implications, including a reduction of the oxidizing power of the atmosphere.