Collaborative efforts towards advancing aerosol assimilation and prediction in the Unified Forecast System at NOAA

An ensemble-variational aerosol data assimilation (DA) system based on the Joint Effort for Data assimilation Integration (JEDI) was recently developed for global aerosol prediction at the National Oceanic and Atmospheric Administration (NOAA) in the U.S.. This system is currently evaluated in the near-real time (NRT) at NOAA/Global Systems Laboratory (GSL) that assimilate NOAA’s operational Visible Infrared Imaging Radiometer Suite (VIIRS) 550 nm aerosol optical depth (AOD) retrievals. Our online NRT evaluation (https://ruc.noaa.gov/projects/nrt/Aerosol-DA/) suggests the resulting AOD analysis significantly improves the agreement with independent AERONET AOD and AOD analyses from NASA and ECMWF. Collaborative efforts across NOAA, the Joint Center for Satellite Data Assimilation and the University of Iowa are established to accelerate the operational aerosol assimilation and prediction in NOAA’s Unified Forecast System. This JEDI-based aerosol DA system is currently extended to NOAA’s future operational aerosol forecast system UFS-Aerosols. It will be used to produce a 2018-2022 global aerosol reanalysis which will benefit the UFS development for the Medium-Range Weather and Subseasonal-Seasonal forecast. We are implementing assimilation of log-transformed AOD within JEDI. This will improve AOD assimilation through better satisfying Gaussian assumptions in the DA update. We recently implemented within JEDI and experimented on assimilation of nocturnal AOD along with NOAA’s operational VIIRS daytime AOD. Nocturnal AOD will complement most operational daytime AOD, offering an excellent opportunity to better capture the diurnal evolution of aerosol events. Results of our NRT aerosol assimilation experiments and impacts of the aforementioned advancements will be presented.
The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)