Actinometric Platform for Solar Spectral and Air Quality Measurements

A new actinometric platform has been installed at National Observatory of Athenson December 2015. The system consists of two sun photometers(PANDORA-2s AND PSR- Precision Spectral Radiometer), both of which measure sun spectrum at very high resolution, providing high temporal information of the radiation field and the aerosol variability. PSR has two separate optical parts, in order to record both Direct and Global Irradiance, which end up at the same spectrometer. The instrument measures in the range 300–1020 nm, with a sampling step of 0.7 nm. Instrument products include absolute spectral direct and global solar irradiance, spectral Aerosol optical depthand water vapor. Absolute Calibration of the instrument was provided by the World Radiation Center (PMOD-WRC), granting very low uncertainty. PANDORA is a spectrometer which records Direct Irradiance at the region 290–520 nm (0.12 nm step), with 1 min frequency. PANDORA measurements are used to retrieve Total Column of O3 and NO2. At this work we present results of the instrument characterization, pilot measurements at two campaigns in Davos, Switzerland and Finokalia, Crete and measurements at Athenscenter from January 2016.