CM SAF Aerosol Optical Depth (AOD) Data Record - Edition 1

This CM SAF climate data record provides daily and monthly estimates of the Aerosol Optical Depth (AOD) derived from the Spinning Enhance Visible and InfraRed
Imager (SEVIRI) sensors onboard the Meteosat Second Generation (MSG) satellites.
Aerosols have many impacts on the climate on our planet: direct through the scattering and absorption of radiation, and also indirectly through
the cloud nucleation and precipitation processes. Concerning the direct effect, the most relevant parameters are the AOD and, to a lesser extent,
the single scattering albedo. In the frame of climate monitoring, the continuous monitoring of those parameters is of prime importance to
understand climate variability and change. Monitoring aerosols is also important as they have in general an adverse effect on the retrieval of
many climate geophysical parameters as, for instance, the surface albedo.
The Land Daily Aerosol (LDA) algorithm is used to process this Climate Data Record of AOD. The algorithm has been developed at
EUMETSAT for AOD estimation, primarily for the MSG/SEVIRI instrument. The algorithm performs, on a daily basis and at full pixel scale, the
inversion of the accumulated solar band observations (0.6μm, 0.8μm and 1.6μm) to estimate simultaneously the AOD (a single value
at reference wavelength of 550nm) and the 4 Rahman-Pinty-Verstraete (RPV) parameters of the surface in the 3 bands. The algorithm performs
therefore an optimization on 13 unknowns (the AOD + 3 x 4 RPV parameters). In addition, the optimization is also done over a set of different
models of aerosol microphysics (single scattering albedo, phase function).
The CM SAF CLAAS-2 cloud mask (DOI:10.5676/EUM_SAF_CM/CLAAS/V002) is used as additional input to perform the cloud screening.
The climate data record covers the period from 1 Feb 2004 to 31 Dec 2012 (Meteosat-8 and -9).