Radiative Impact of Aerosol–Cloud Interactions: Comparison between Models and Observations (Invited Presentation)

There are numerous possible pathways for aerosol-cloud-climate interactions in regimes of shallow clouds, varying among other things with dominant aerosol and cloud type.

Here we illustrate some of these relations using in-situ measurements, satellite observations re-analysis and global models to investigate co-variations between aerosol and cloud properties,

with examples ranging from suppression of boundary layer turbulence in the presence of absorbing aerosols to predictability of cloud droplet number concentration from sulfate mass concentration.

Despite correlations between aerosol and microphysical cloud properties, however, radiative effects of aerosol-cloud interactions on greater spatial and temporal scales are not necessarily easily observable. Here we discuss discrepancies between models and observations in terms of radiative impacts of aerosol-cloud interactions, focusing on cloud albedo effects, investigating reasons for disagreement and possible remedies and model improvement.

We further discuss the use of correlations between various micro- and macro physical cloud and aerosol properties, as a means for constraining models and their representation of aerosol-cloud-climate interactions.