Sensitivity Study Of The Initial Meteorological Fields On The Pm 10 Concentration Predictions Using Cmaq Modeling

Sensitivity analysis on PM10 forecasting simulations was carried out by using two different initial and boundary conditions of meteorological fields: NCEP/FNL (National Centers for Environmental Prediction/Final Analysis) reanlaysis data and NCEP/GFS (National Centers for Environmental Prediction/Global Forecast System) forecasting data, and the comparisons were made between two different simulations. The two results both yielded lower PM10 concentrations than observations, with relatively lower biased results by NCEP/FNL than NCEP/GFS. We explored the detailed individual meteorological variables to associate with PM10 prediction performance. With the results of NCEP/FNL outperforming GFS, our conclusion is that no particular significant bias was found in temperature fields between NCEP/FNL and NCEP/GFS data, while the overestimated wind speed by NCEP/GFS data influenced on the lower PM10 concentrations simulation than NCEP/FNL, by decreasing the duration time of high-PM10 loaded air mass over both coastal and metropolitan areas. These comparative characteristics of FNL against GFS data such as maximum 3 similar to 4 m/s weaker wind speed, PM10 concentration control with the highest possible factor of 1.3 similar to 1.6, and one or two hour difference of peak time for each case in this study, were also reflected into the results of statistical analysis. It is implying that improving the surface wind speed fluctuation is an important controlling factor for the better prediction of PM10 over Korean Peninsula.