Gas–particle interactions of tropospheric aerosols: Kinetic and thermodynamic perspectives of multiphase chemical reactions, amorphous organic substances, and the activation of cloud condensation nuclei

Aerosols are of central importance in the Earth system, influencing the atmosphere, biosphere, climate, and public health. This article outlines recent advances and perspectives in the investigation and effects of gas–particle interactions in tropospheric aerosols, including physical, chemical and biological aspects. In particular, it addresses how multiphase processes and heterogeneous chemical reactions can be efficiently described by kinetic models, how amorphous organic substances can influence the kinetics of water uptake and phase transitions, and how the abundance and activation of cloud condensation nuclei (CCN) depend on thermodynamic and kinetic parameters.

► Multiphase processes and heterogeneous reactions described by kinetic flux models.
► Amorphous organics influence water uptake and phase transitions of aerosol particles.
► Thermodynamics of cloud condensation nuclei described by kappa-Köhler models.
► Aerosol- and updraft-limited regimes of CCN activation and cloud droplet formation.