Abstract
Method for aerosol refractive index estimation with ground based polarization measurement data is proposed. The proposed method uses a dependency of refractive index on p and s polarized down welling solar diffuse irradiance. It is much easy to measure p and s polarized irradiance on the ground with a portable measuring instrument rather than solar direct, diffuse and aureole measurements. Through theoretical and simulation studies, it is found that the proposed method show a good estimation accuracy of refractive index using measured down welling p and s polarized irradiance data with a measuring instrument pointing to the direction which is perpendicular to the sun in the principal plane. Field experimental results also show a validity of the proposed method in comparison to the estimated results from the conventional method with solar direct, diffuse and aureole measurement data.
Highlights
The largest uncertainty in estimation of the effects of atmospheric aerosols on climate stems comes from uncertainties in the determination of their microphysical properties, including the aerosol complex index of refraction, which in turn determines their optical properties
It is found that the measured DP and calculated DP derived from MODTRAN show a good coincidence with below 10% of discrepancy
It is found that the estimated aerosol refractive index and size distribution (Junge parameter) based on the proposed method and those derived from the skyradiometer data of solar direct, diffuse, and aureole based on skyradpack with below 6% of discrepancy
Summary
The largest uncertainty in estimation of the effects of atmospheric aerosols on climate stems comes from uncertainties in the determination of their microphysical properties, including the aerosol complex index of refraction, which in turn determines their optical properties. Refractive index and size distribution as well as single scattering albedo, Angstrome exponent, volume spectrum are, in general, estimated with ground based solar direct, diffuse and aureole data together with measured optical depth. Instrument that allows measurement is, in general, comparatively heavy and relatively large in comparison to the sun-photometer and polarized irradiance measuring instruments. They are not portable so that it is difficult to measure solar direct, aureole and diffuse irradiance at anywhere. It depends on surface reflectance so that surface reflectance, optical depth of molecule, aerosol and the other atmospheric components have to be known, it might be possible to estimate DP results in estimation of refractive index and size distribution
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: International Journal of Advanced Computer Science and Applications
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
