Dr. Mariusz Pagowski pioneered assimilation of chemical species at NOAA in application to forecasting ozone and fine particulate matter PM2.5 with regional models WRF-Chem (Weather Research and Forecasting - Chemistry, Grell et al., 2005) and CMAQ (Community Multiscale Air Quality, Binkowski et al., 2003) using variational and ensemble techniques (Pagowski et al., 2010; Pagowski and Grell, 2012; Pagowski et al., 2014). More recently, in a collaboration with NASA he is leading an effort to develop first ever aerosol reanalysis at NOAA (“Joint NOAA-NASA Development of a Data Assimilation System for Aerosol Reanalysis and Forecasting”, 2018-2022, NA18OAR4310281). The reanalysis for year 2016 obtained by assimilating Moderate Resolution Imaging Spectroradiometer (MODIS) Aerosols Optical Depth (AOD) retrievals to GEFS-Aerosols forecasts is currently being archived at the National Centers for Environmental Information (NCEI) for public distribution. The assimilation system relies on the hybrid 3D-Ensemble-Variational (3D-EnVar) approach using computer codes from JEDI. The reanalysis compares favorably with NASA’s Modern-Era Retrospective analysis for Research and Applications version 2 (MERRA-2, Randles et al., 2017; Buchard et al., 2017) and ECMWF’s Copernicus Atmosphere Monitoring Service interim Reanalysis (CAMSiRA, Inness et al., 2013; Flemming et al., 2017) and verifies well against AERONET observations. In parallel, Dr. Pagowski leads the execution of a proposal to develop near-real-time (NRT) global DA system for forecasting aerosols at NOAA/NCEP/EMC (“Development of the National Global Data Assimilation Ensemble-Based System for Forecasting of Aerosols”, 2019-2022, NA19OAR4590080). In this implementation, observations are Visible Infrared Imaging Radiometer Suite (VIIRS) AOD retrievals and the model is GEFS-Aerosols supplemented with stochastic perturbations to source emissions. During the course of the execution of these two proposals, the JEDI system was enhanced by computer codes for formatting AOD retrievals, two forward AOD operators, and aerosol interfaces in variational solver and Kalman filter. Good performance of the assimilation system implemented in NRT at NOAA/ESRL/GSL has been demonstrated in multiple presentations at various venues (e.g. Huang et al., 2020, Huang et al., 2021a) and a manuscript on this topic is in preparation.