The CM SAF is happy to announce the release its Climate Data Record of Aerosol Optical Depth (AOD) derived from the Spinning Enhance Visible and InfraRed Imager (SEVIRI) sensors onboard the Meteosat Second Generation (MSG) satellites. This record covers the period from 1 Feb 2004 to 31 Dec 2012 (Meteosat-8 and -9) and consists of daily and monthly means of AOD.
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 geophysical parameters relevant for climate as, for instance, the surface albedo.
The Land Daily Aerosol (LDA) algorithm, developed at EUMETSAT, is used to process this CDR of AOD. 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).
An example of monthly mean AOD product is shown in Figure 1.
Along with the data and the uncertainty estimates, a comprehensive documentation including product user manual, algorithm descriptions, and validation report is provided. The documents and the data record can be accessed from the DOI landing page: https://doi.org/10.5676/EUM_SAF_CM/MSG_AOD/V001
References: - Govaerts, Y. M., Wagner, S., Lattanzio, A., & Watts, P. (2010). Joint retrieval of surface reflectance and aerosol optical depth from MSG/SEVIRI observations with an optimal estimation approach: 1. Theory. Journal of Geophysical Research: Atmospheres, 115(D2). - Wagner, S. C., Govaerts, Y. M., & Lattanzio, A. (2010). Joint retrieval of surface reflectance and aerosol optical depth from MSG/SEVIRI observations with an optimal estimation approach: 2. Implementation and evaluation. Journal of Geophysical Research: Atmospheres, 115(D2). NC / Dec 2017