Spectral aerosol optical thickness is retrieved simultaneously with the determination of spectral ground reflectance by the Bremen AErosol Retrieval (Baer). The retrieval of AOT provides for 7 short-wave channels of the MERIS instrument the spectral behaviour of AOT, which is used for the determination of the spectral slope in terms of the Ångström -parameter. Ångström is obtained using AOT, retrieved from the 7 MERIS channels with wavelength 0.665 µm.

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Satellite: ENVISAT (ESA)
Instrument(s): MERIS
Instrument/algorithm PI: Günther Rohen, IFE Bremen
Contact details: rohen[at]
Parameter(s): spectral AOT, Ångström exponent
Aerosol algorithm: BAER
Cloud screening: ESA L2 MERIS cloud screening
Aerosol model: LACE-98
Retrieval assumptions: surface reflectance from vegetation cover and model reflectance spectra, AOT from LUT
Retrieval limitations: no TIR channels for cloud screening on MERIS
Spatial, temporal coverage: 2005/2006, Germany / SAMUM campaign (Morocco)
Spatial, temporal resolution: 1km / 1150km swath / 35 days repeat cycle
Operations status: experimental
Validation status:
Quality control:
last algorithm version:
last validation:



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