Effects of analysis nudging in the meteorological model for air quality modeling

Monday, 15 December 2014
JungWoo Yoo, HwaWoon Lee and Won-Bae Jeon, Pusan National University, Busan, South Korea

The causes of reducing the accuracy for forecasting of PM concentrations are uncertain emissions, initial and boundary conditions and results of meteorological model. Especially, analysis nudging is a method for improving results of the meteorological model. This study includes evaluation of the meteorological simulation showing the impact with and without nudging in WRF during a high concentration PM10 episode in the Korean Peninsula. In NN (No nudging) case, anticyclonic center is located on the west side of the Shanghai. However YN (Yes nudging) case with nudging horizontal wind were well captured anticyclonic center shifted toward west compared with NN case. As a result, the airflow entering the Korean peninsula changes in the southwest (NN case) to west wind (YN case). Further YN case with nudging water vapor mixing ratio was underestimated RH (Relative Humidity) and total precipitation than NN case. These results are affected transport and deposition of air pollutants such as PM.