The regional air quality model WRF/CMAQ combined with sensitivity tests was used to study the reduction of ozone pollution peak in Foshan

a city in the center of the Pearl River Delta (PRD). Sensitivity tests based on the WRF/CMAQ model included reducing the emissions of two O

3

precursors (VOCs and NO

x

) and reducing the emissions from traffic

industries (excluding solvents)

and solvents in Foshan

respectively. The results showed that the ozone pollution in Foshan City was most sensitive to VOCs. Reducing the emission of VOCs by 30% decreased the ozone peak concentration by up to about 10%. However

the reduction of NO

x

emissions increased the ozone concentrations in some areas. Reduction in emissions of traffic and industrial sectors led to increase or decrease of ozone concentrations in different areas because VOCs and NO

x

emissions were reduced simultaneously. The major emission species in the solvent industry were VOCs. It could significantly decrease ozone peak concentration when reducing the emissions of the solvent industry. Therefore

the solvent industry was the key sector of ozone peak reduction. This study also conducted sensitivity tests of reducing emissions for different days ahead. The results showed that the effects of reducing emission for 1-day in advance were better than 0-day but not significantly different from 2-day and 3-day in advance. In conclusion

reducing emissions 1-day in advance was the most effective and economical control strategy to reduce the peak of ozone in Foshan city area.