The Effect of Aerosol Absorption in Solar UV Radiation
We have used a combination of a CIMEL sun-photometer and a UV multi-filter radiometer (MFR) in order to calculate columnar aerosol absorbing properties such as the single scattering albedo (SSA) in the Ultraviolet (UV) range in Athens area. Such calculations are hardly to be found since most UV related applications use SSA retrievals from the visible range assuming wavelength independent aerosol absorbing coefficients going from the visible to the UV range. Our results showed significantly reduced SSA values (higher absorption) comparing the CIMEL/AERONET SSA retrievals at 440 nm with the UV-MFR ones. In addition, we calculated lower SSA values for lower aerosol optical depth values and a seasonal variation of SSA with lower values for wintertime and higher in the summertime for all wavelengths. The effect of such SSA differences in the calculation of the UV spectral irradiances varies from 2% to10% and it is proportional to the solar zenith angle and the aerosol load.
KeywordsAerosol Optical Depth Solar Zenith Angle Radiative Transfer Model Ozone Monitoring Instrument Single Scattering Albedo
SK would like to acknowledge the Marie Curie project ACI-UV, PERG05-GA-2009-247492.
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