Aerosol retrievals from METEOSAT-8

A user requirements and feasibility study is performed to assess the applicability of the Spinning Enhanced Visible and Infrared Imager (SEVIRI) onboard Meteosat Second Generation (MSG) for retrieving aerosol properties and follow their evolution during the day. An overview is given of state of the art algorithms that are used to retrieve aerosol properties from today’s operational satellites, such as MODIS and MERIS. The applicability of SEVIRI for aerosol retrievals is demonstrated with Aerosol Optical Thickness (AOT) retrievals from a simple algorithm. Fifteen days of SEVIRI observations is used to derive clear sky surface reflectance maps, taking advantage of the high temporal resolution of MSG. The SEVIRI retrievals of AOT are compared to ground-based observations of AOT from AERONET.
The results show the potential of SEVIRI to retrieve AOT and follow the diurnal evolution of AOT. The high temporal resolution and stable viewing geometry of MSG allows for the retrieval of very accurate surface reflectance maps. Due to these maps the aerosol properties can be retrieved both over ocean and land surfaces. The latter is an improvement compared to AOT retrievals from polar orbiting satellites, which can only retrieve AOT over dark surfaces because of uncertainties in surface reflectance maps. The SEVIRI and AERONET retrieved AOT values are in the same order and show similar diurnal variations, provided the aerosol type is known.