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

CHAPTER 6
VALIDATION OF SMOKE AND DUST AEROSOLS DETECTION
WITH MULTI-SENSOR
In Chapters three and four, the detection of smoke and dust aerosols is performed by
combining MODIS RSB and TEB measurements based on the multi-spectra technique.
The detection results are validated roughly with MODIS true color images. Visual
validation provides, however, only basic verification. Validating results with the same
sensor offers relatively low confidence. The further quantitative validation with other
sensors, such as OMI and CALIPSO, is executed in this chapter.
6.1 Validation of Aerosol Detection with OMI
OMI onboard EOS AURA is one of key instruments designed for monitoring the
ozone and other atmospheric species including aerosols. It is a hyperspectral sensor,
observing the solar backscatter radiation in the ultraviolet (UV) and visible spectrum
(Ahmad et al., 2003; Levelt et al., 2000). The wavelengths and algorithms used for
retrieving OMI aerosol parameters are significantly different from those of MODIS.
These differences produce some advantages, such as the high sensitivity of the OMI UV
retrieval algorithm to aerosol absorption and the ability to retrieve aerosol information
over bright surfaces and clouds (Livingston et al., 2007). Moreover, both AURA and
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