There exist a broad range of possible pathways for aerosol influence on the Earth’s energy budget and climate. Some include cooling and heating by reflection and absorption of solar radiation, and alteration of cloud properties.
In Reviews of Geophysics, Bellouin et al.  provide a framework for encompassing all these effects of atmospheric particles. In a commentary in AGU Advances, Bender  responds and adds to the review article by pointing to issues that require additional consideration. For example, what was the content of particles in the preindustrial atmosphere? Also, because the effects of aerosols can depend on the particle composition, the dependence of radiative effects on composition must be understood. This commentary adds further insights to uncertainties in the complexity of particle effects on climate.
Citation: Bender, F. . Aerosol forcing – still uncertain, still relevant. AGU Advances, 1, e2019AV000128. https://doi.org/10.1029/2019AV000128
—Don Wuebbles, Editor, AGU Advances