A method of automatically determining a measure of atmospheric aerosol optical
properties using a multi- or hyper-spectral, multi-pixel image. A plurality of
spectrally-diverse pixels are resolved from the image. A statistical spectral deviation
of the spectrally-diverse pixels is determined, and then corrected for non-aerosol
transmittance losses. One or more wavelength-dependent aerosol optical depths are
derived from the statistical spectral deviation. Wavelength-dependent gaseous optical
depths can be derived from the statistical spectral deviation.