i Detection of Smoke and Dust Aerosols Using Multi-sensor Satellite ...

eflectance in red band. Therefore, the dust aerosol pixels are sorted into several
categories according to their reflectance at the red band, given in Fig. 6.7. There are 204
pixels identified and only 18 pixels unidentified. About 91.89% dust aerosol pixels
obtained from proposed multi-spectral detection algorithm are correctly identified by
comparing with CALIPSO VFM data product. Additionally, there are 21 pixels
misidentified. Actually, the statistical analysis shows that most heavy dust aerosol pixels
are identified. Unidentified and misidentified dust aerosol pixels are mostly concentrated
in the low reflectance range at the red band, namely low dust aerosol loading. Fig. 6.8
displays the profile of dust storm in the sensor motion direction using the reflectance at
the red band. In the image, the errors (unidentified or misidentified) are located only at
the margin of the dust storm with light aerosol loading. Consequently, the multi-spectral
algorithm for dust aerosol detection by MODIS works fairly well over bright surface,
based on the validation with the CALIPSO VFM data product.
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