Balance of emission and dynamical controls on ozone during the Korea-United States Air Quality Campaign from multiconstituent satellite data assimilation

Global multiconstituent concentration and emission fields obtained from the assimilation of the satellite retrievals of ozone, CO, NO2, HNO3, and SO2 from the Ozone Monitoring Instrument (OMI), Global Ozone Monitoring Experiment 2, Measurements of Pollution in the Troposphere, Microwave Limb Sounder, and Atmospheric Infrared Sounder (AIRS)/OMI are used to understand the processes controlling air pollution during the Korea-United States Air Quality (KORUS-AQ) campaign.

Estimated emissions in South Korea were 0.42TgN for NOx and 1.1Tg CO for CO, which were 40% and 83% higher, respectively, than the a priori bottom-up inventories, and increased mean ozone concentration by up to 7.51.6ppbv. The observed boundary layer ozone exceeded 90ppbv over Seoul under stagnant phases, whereas it was approximately 60ppbv during dynamical conditions given equivalent emissions. Chemical reanalysis showed that mean ozone concentration was persistently higher over Seoul (75.107.6ppbv) than the broader KORUS-AQ domain (70.59.2ppbv) at 700hPa.