Remote sensing of atmospheric nanoparticles and effect of wavelength on the size estimation

Nano-size suspended particles in atmosphere like marine salt, volcanic dust, biological debris, soot and industrial dust are collectively called aerosols, which have intense effect on the extinction of solar and terrestrial radiation. The radiation extinguishing property is quantified in terms of optical depth, a key parameter for aerosol size estimation through remote sensing. The present work studies the determination of aerosol optical depth at urban area with both ground based radiometric measurement and satellite image analysis using shorter and longer wavelengths of radiation in ultraviolet-visible-near-infrared range. It is concluded that the use of longer wavelengths yields more consistent result and the data obtained from shorter wavelengths get masked by Rayleigh scattering effect.