Aerosol Data Assimilation for Regional Weather and Air-Quality Forecasts Using WRF/Chem
The newly-developed system was firstly applied to a dust storm over East Asia by assimilating MODIS 0.55 μm total aerosol optical depth (AOD) retrieval products using the JCSDA's CRTM as the observation operator which led to substantial improvement for WRF/Chem air-quality forecasts when compared to independent aerosol data sources. Simultaneous assimilation of AOD and surface PM2.5 observations was then demonstrated over North American for a month-long period. The deficiency of assimilating MODIS AOD over western US desert area, where retrieval quality is problematic, was identified.
More recent studies have focused on the impact of aerosol data assimilation on weather forecasts for a US wildfire event and an Atlantic tropical cyclone case. The results indicate that more accurate aerosol analyses from assimilating MODIS AOD observations lead to more realistic simulation of direct radiation effect for both the US wildfire event and the Atlantic Saharan Air Layer.