Ozone Simulations over the Seoul Metropolitan Area for a 2007 June Episode, Part I: Evaluating Volatile Organic Compounds Emissions Speciated for the SAPRC99 Chemical Mechanism

摘要: Volatile organic compound (VOC) emissions in the 2007 CAPSS (Clean Air Protection Supporting System) inventory are chemically speciated for SAPRC99 (Statewide Pollution Research Center 99) mechanism, following Source Classification Code (SCC) matching method to borrow U.S.EPA`s chemical speciation profiles. CMAQ simulations with High-order Direct Decoupled Method (HDDM) turn applied evaluate uncertainty by comparing simulated model VOC species observations Seoul Metropolitan Area (SMA) a June episode. Simulations under-predicted ALK1 ALK4 factor of 2 5 and over-predicted ALK5 7.5 while ARO1, ARO2, OLE1, ethylene (ETH) comparable observations, showing relative difference 10 30%. OLE2 roughly 4 times overestimated. Emission rates individual revised referring ratio observed concentrations. Impact emission changes on overall ozone prediction was insignificant days which 1-hr maximum lower than 100 ppb. However, showed ppb when high above 120 vicinity Seoul. This result suggests that evaluations be necessary lead control plans right direction. Moreover, ratios ARO1 ARO2 50% ones, imply adjustment may required mimic real VOC/ condition over area.