Particulate matter (PM) from human activities cools the Earth by scattering solar radiation. However, coarser dust particles exert a warming effect. This study investigates the radiative effects of sulfate-containing aerosols using Mie scattering and 3D finite-difference time-domain simulations. The findings reveal that fine, non-light-absorbing inorganic aerosols like sulfate can also have a warming effect due to their absorption and re-emission of thermal radiation under resonance conditions at long wavelengths. These effects should be considered when assessing aerosol contributions to climate change.
