Aerosols play an important role in Earth’s radiation budget and hydrological cycles, climate, air quality, and human health. In this session we invite submissions that synergistically use Earth observations and modeling to characterize aerosol distribution, size, and speciation for air quality and climate applications. Current and future global observations from spaceborne instruments on board Geostationary (e.g., ABI, AHI, AMI, TEMPO, etc.) or Polar Orbiting platforms (e.g., MODIS, MISR, POLDER, VIIRS, OMPS, OCI, HARP, SPEX, 3MI, MAIA, ACCP, etc.), together with ground-based observations (e.g., AERONET, MPLNET, SPARTAN etc.) are essential to inform on the aerosol state today and within the next decade(s) but many limitations remain. As the assimilation of observations in models progresses, the separation between observations and simulations becomes blurry. This year, presentations that focus on synergetic approaches that incorporate model, ground-based, as well as satellite and suborbital observations to improve understanding of aerosol distributions and processes are encouraged.