Implementation of aerosol data assimilation in WRFDA (v4.0.3) for WRF-Chem (v3.9.1) using the RACM/MADE-VBS scheme

[摘要] The Weather Research and Forecasting model data assimilation (WRFDA) system, initially designed for meteorological data assimilation, is extendedfor aerosol data assimilation for the WRF model coupled with chemistry (WRF-Chem). An interface between WRF-Chem and WRFDA is built for the RegionalAtmospheric Chemistry Mechanism (RACM) chemistry and the Modal Aerosol Dynamics Model for Europe (MADE) coupled with the Volatility Basis Set (VBS)aerosol schemes. This article describes the implementation of the new interface for assimilating PM 2.5 and PM 10 as well as fourgas species ( SO 2 , NO 2 , O 3 , and CO) on the ground. The effects of aerosol data assimilation are briefly examined through amonth-long case study during the Korea–United States Air Quality (KORUS-AQ) period. It is demonstrated that the improved chemical initialconditions through the 3D-Var analysis can lead to consistent forecast improvements up to 26 %, reducing systematic bias errors in surface PM 2.5 ( PM 10 ) concentrations to 0.0 ( − 1.9)  µg m −3 over South Korea for 24  h .

[学科分类] 土木及结构工程学