Aerosol retrievals from METEOSAT-8 - CM SAF

SAF on Climate Monitoring Visiting Scientists Report Doc. No: 1.0
Issue : 1.0
Date : 4 October 2006
the compositing time and the compositing period itself T comp
- Accurate radiative transfer with multiple scattering, including sphericity of the atmosphere for
large angles.
Then a lot of work could be done to improve this one-channel algorithm. Several questions have to
be answered first:
- To what extent can the aerosol properties be considered stable at a particular location within a
couple of hours or an entire day in order to exploit the multi-angular information of SEVIRI
measurement and thus to better constrain the aerosol model
- To what extend can the HRV channel help improve the spatial resolution and the spectral
dependence of the aerosol scattering properties toward the blue
The preliminary results of this study demonstrated the potential of SEVIRI to retrieve aerosol
properties. The comparisons with AERONET data are very promising and showed that SEVIRI
could be used to derived AOT values. In general the variability is well reproduced, although some
stations show biases between MSG and AERONET. There are several suggestions for improving
the presented aerosol retrieval algorithm, and develop a mature algorithm for accurate monitoring of
the diurnal variability (15 minutes time sampling) in aerosol load at a spatial resolution of around 5
km. This would be a unique data set that cannot be derived from polar platforms. MSG/SEVIRI
aerosol retrievals are possible both over dark targets (ocean and forest) and brighter targets over
land (limitations must be taken into account for very bright target such as desert), because surface
reflectances can be determined with a high accuracy. The latter is an improvement as compared to
retrievals from polar orbiters such as MODIS.
References
Borde, R., Ramon, D., Schmechtig, C., and Santer, R., “Extension of the DDV concept to
retrieve aerosol properties over land from the Modular Optoelectronic Scanner sensor”,
International Journal of Remote Sensing, 24, 1439-1467, 2003.
Hess, M., Koepke, P., Schult, I. Optical properties of aerosols and clouds: the software package
OPAC. Bull. Amer. Meteor. Soc. 79, 831-844, 1998.
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