6. CONCLUSIONS 
Operational correction of the aerosol effect on remote sensing of the surface over the 
land still forms an unresolved challenge. The new generation of satellite sensors for global 
remote sensing of the earth surface, with better and more numerous spectral channels 
(mainly the addition of a blue channel and a channel at 2.1 pm), finer spatial resolution and 
precision calibration will offer new opportunities for remote sensing and for correction for 
the aerosol effect. Direct and indirect correction methods are possible and were reviewed in 
this paper. The direct method identifies dark pixels using the mid-IR channels, estimates 
their reflectance in the red and blue channels and determines the aerosol optical thickness 
that is used in the correction. The indirect method is based on a remote sensing function 
such as the Atmospheric Resistant Vegetation Index, ARVI, that is much less sensitive to 
aerosol effect than regular remote sensing methods. Atmospheric correction methods will 
be assisted by aerosol climatology derived from ground based measurements with networks 
of automatic sun/sky radiometers. These data will also be used for validation of the aerosol 
properties derived from the satellite data in the correction process. Results from field 
experiments show that satellite remote sensing of polarization planed in the future may 
provide additional tools for estimation of the aerosol loading used in the correction. 
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