Invited Presentation: Aerosol indirect radiative forcing quantification from different data sources

Typically, general circulation models are used to quantify the radiative forcing due to the modification of cloud radiative effects by anthropogenic aerosols. Satellite data have been used to assess at least the basic (“first”) aerosol indirect effects, and have also been used to constrain climate model parameterisations and subsequently the radiative forcing. Recently, a reanalysis of aerosols assimilating aerosol satellite observations has been used for an assessment of the aerosol indirect effect as well. This presentation will discuss, compare and assess the different methods to quantify the aerosol indirect forcing. The uncertainty range is quantified and yields a larger range than previous assessments by, e.g., the IPCC.