Atmospheric aerosols were measured during 2007-2008 at the Observatory of Atmospheric Research, in Phimai, Thailand, one of the stations of SKYNET. Aerosols were much higher in dry season than in wet season. The concentration ratio of elementary carbon to sulfate in dry seasons revealed that polluted air masses arrived at Phimai from east Asia in the first season, and from Indochina where biomass burning were active in the latter season. According to the optical measurement by sky radiometer, aerosol optical thickness (AOT) was lower in wet season than in dry season, while single scattering albedo (SSA) was much higher in wet season. Both AOT and SSA mostly corresponded to the seasonal variation in atmospheric aerosols. SSA reached the minimum in the middle of dry season when EC reached the maximum. The vertical profile of aerosol and cloud by the satellite data of CALIPSO was consistent with AOT by sky-radiometer.
Carbonaceous aerosols, Biomass burning, Optical properties, Skyradiometer, Climate change