Numerical study of boundary layer ozone transport and photochemical production in east Asia in the wintertime

Meigen Zhang, I. Uno, S. Sugata, Z. Wang, D. Byun, and H. Akimoto

Geophys. Res. Lett., 29(11), 10.1029/2001GL014368, 2002.


The transport and chemical transformation of boundary ozone in East Asia in January 1997 was investigated by use of the Models-3 Community Multi-scale Air Quality (CMAQ) modeling system with meteorological fields calculated from the Regional Atmospheric Modeling System (RAMS). The predicted ozone concentrations were compared with ground-level observations at four remote sites in Japan and were found that the model reproduces many of the important observed features. Examinations of several observed high ozone episodes found that these elevated ozone levels were in association with continental outflows, and the model calculated positive net ozone production rate in the daytime over the lower marine atmosphere, which was evident in the observations, implies the critical role of fast transport of ozone precursors from the Asia continent. The ozone budget analysis in the model indicates that the supply and loss of boundary layer ozone in East Asia are dominated by photochemistry.