Comparative evaluation of the impact of WRF–NMM and WRF–ARW meteorology on CMAQ simulations for O3 and related species during the 2006 TexAQS/GoMACCS campaign

In this paper, impact of meteorology derived from the Weather, Research and Forecasting (WRF)– Non–hydrostatic Mesoscale Model (NMM) and WRF–Advanced Research WRF (ARW) meteorological models on the Community Multiscale Air Quality (CMAQ) simulations for ozone and its related precursors has been comparatively evaluated over the eastern United States using surface network (AIRNow) data and over the Texas area with the intensive observations obtained by NOAA aircraft P–3 flights and ship during the 2006 TexAQS/GoMACCS campaign. The NMM–CMAQ and ARW–CMAQ models were run on the basis of their original grid structures of the meteorological models. The results at the AIRNow surface sites showed that the model performance for ARW–CMAQ and NMM–CMAQ models was similar and reasonable for the high maximum 8–hr O3 concentration range (>40 ppbv) with slightly better performance for ARW–CMAQ [the normalized mean bias (NMB) values of ARW–CMAQ and NMM–CMAQ are 8.1 and 9.4%, respectively]. The results of the evaluation using aircraft observations over the Houston–Galveston–Brazoria and Dallas metropolitan areas revealed that both models had similar performances for different chemical species (O3, CO, PAN, NO2, NO, NOX, HNO3, NOY and ethylene) as both models use the same chemical mechanism and emissions. Both models reproduced the vertical variation patterns of the observed air temperature and water vapor well with the slightly lower values for the ARW–CMAQ model. The evaluation results with ship observations over the Gulf of Mexico showed that both models captured, with a good deal of accuracy, the temporal variations and broad synoptic change seen in the observed O3, NOY, CO and O3+NO2 with the mean NMB value <25% most of the time.