Process Analysis of Ozone Formation in Guangzhou: Application of Observation-Based Model

An observation-based model(OBM) was used to analyze the process of ozone formation in Guangzhou area in the summer and autumn of 2000.The concentration change and relations of ozone and its precursors at Guangzhou Environmental Protection Institute(GEPI) and two downwind suburban areas,Huadu and Xinken,in July and November 2000 were analyzed.On this basis,the OBM was applied to preliminarily simulate the photochemical process and discuss the type of photochemical reaction at these areas.The results showed: in July,the relative incremental reactivity(RIR) of AHC was greater than that of NO and the ozone formation was in VOC-control condition at GEPI,while the RIR of NO was greater than that of AHC and the ozone formation was in NO_x-control condition at its downwind Huadu;in November,the RIR of AHC was greater than that of NO and the ozone formation was in VOC-control condition at GEPI,while the RIR of NO was greater than that of AHC and the ozone formation was in NO_x-control condition at its downwind Xinken.The results were comparable to those applied with AQM method in this region.