Intercomparison of Aerosol Optical Properties Derived from PREDE Skyradiometer and CIMEL Sunphotometer Measurements for the DRAGON-Korea Campaign

The Distributed Regional Aerosol Gridded Observation Networks (DRAGON) campaign for validation of satellite aerosol products and comparison/validation of ground-based aerosol retrievals has been launched in Asia. It was conducted in Korea (DRAGON-Korea) between March and May 2012, with CIMEL sunphotometers being operated at around 20 sites throughout the country. The Hankuk University of Foreign Studies site (Hankuk_UFS, 37.02oN, 127.16oE, 167 m above sea level) is located about 35 km southeast of downtown Seoul. A PREDE skyradiometer (POM-02) is operated along with CIMEL sunphotometer (CE 318-1) to compare the aerosol optical properties derived from the two instruments. The operation for intercomparison study started with the DRAGON-Korea campaign and will continue for a year. POM-02 and CE 318-1 measure diffuse radiation at 6-minute intervals and 11 wavelengths and at 1-hour intervals and 4 wavelengths, respectively. Aerosol optical depths from these two instruments are compared at 440, 675, 870, and 1020 nm when the measurement time coincides within 3 minutes. Other aerosol optical properties such as Angstrom exponent and single scattering albedo (SSA) from the two instruments are also compared in a similar way. It is reported that SSA from the skyradiometer tends to be larger than that from sunphotometer. Factors causing the difference are closely examined.