Influences due to calibration accuracy of skyradiometer which allows aerosol refractive index and size distribution estimations together with influences due to size distribution estimation accuracy on vicarious calibration accuracy of spaceborne based visible and near infrared radiometers

Abstract

In order to improve vicarious calibration accuracy in solar reflectance channels of radiometer onboard satellite, influences due to calibration accuracy of skyradiometer which allows aerosol refractive index and size distribution estimations together with influences due to size distribution estimation accuracy on vicarious calibration accuracy of spaceborne based visible and near infrared radiometers are clarified. It is found that 10% of estimate errors of aerosol refractive index and size distribution are corresponding to 1.3% of Top of the Atmosphere (TOA) radiance. It is also found that the difference between volume spectra of aerosol size distribution derived TOA radiance and Power law of Junge distribution derived TOA radiance is within 2%. Volume spectra of aerosol distribution requires heavy and large radiometer which allows measurement of solar direct, diffuse and aureole like skyradiometer while Junge distribution require just spectral optical depth measurements only with light and small measuring instrument.