Aerosols affect both directly (by scattering and absorbing radiation) and indirectly (by serving as nuclei for cloud droplets) the Earth's climate. Anthropogenic activities have resulted in increased emissions of aerosol particles and thus in increase of cloud condensation nuclei (CCN). The effective radiative forcing due to this increase in aerosols is the most uncertain component of historical radiative forcing of Earth's climate. The most significant part of this aerosol related uncertainty is linked to the aerosol cloud interactions (ACI) and to the effective radiative forcing that they cause. The overall goal of the proposed study is to reduce the current uncertainty in aerosol forcing arising from aerosol cloud interactions by carefully selected steps to improve the accuracy of both the remote sensing measurements and inference methods involved.

2024

2028