Comparing estimates from the R-LINE near road dispersion model using model-derived and observation-derived meteorology

Özet

Observed meteorological conditions, usually measured at airports or weather monitoring stations, have longprovided the only source of meteorology for many Gaussian air pollution dispersion models. This introducesuncertainty and limitations in numerical model estimates, especially for locations of interest far removed fromthese monitoring stations. Hence, it is advantageous to employ predicted meteorology from a prognostic meteorologicalmodel as a substitute. The objective of this study was to compare estimates from the R-LINE nearroad dispersion model at three inland sites and one coastal site in Connecticut using observation-derived(weather station) and model-derived (Weather Research and Forecasting Model) meteorology. Both the graphicaland statistical comparisons indicated less pronounced discrepancies in model estimations in the timeperiods generally characterized by unstable atmospheric conditions than those characterized by stable atmosphericconditions. There were also more pronounced differences at larger distances from roadways. Comparisonof the estimated surface characteristic variables using both the observation-derived and model-derived meteorologydisplayed similar diurnal trends.