Aerosol Optical Properties Retrieved from a Prede Sky Radiometer over an Urban Site of Beijing, China

Journal of the Meteorological Society of Japan. Ser. II

Xiaoye ZHANG¹  Guangyu SHI²  Junying SUN¹  Tamio TAKAMURA³  Hujia ZHAO¹  Huizheng CHE¹  Yaqiang WANG¹  Hong WANG¹  Pradeep KHATRI³  Teruyuki NAKAJIMA⁴ 

[1] Key Laboratory for Atmospheric Chemistry (LAC), Institute of Atmospheric Composition, Chinese Academy of Meteorological Sciences (CAMS), China;State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG), Institute of Atmospheric Physics, Chinese Academy of Sciences, China;Center for Environmental Remote Sensing, Chiba University, 1-33 Yayoi-cho, Chiba, Japan;Atmosphere and Ocean Research Institute (AORI), The University of Tokyo, Kashiwa, Japan

关键词: sky radiometer;    SKYRAD.pack software;    aerosol optical properties;    Beijing;   

DOI  :  10.2151/jmsj.2014-A02

学科分类：大气科学

来源: Meteorological Society of Japan

【 摘 要 】

 SKYNET is an international research network of ground-based Prede sky radiometers for the observation and monitoring of aerosol-cloud-radiation interactions in the atmosphere. The algorithm developed by SKYNET is SKYRAD.pack, which can be used to process the measurement data of Prede instruments. In this study, the latest SKYRAD.pack software (Version 5.0) has been used to retrieve the aerosol optical properties measured by a SKYNET Prede sky radiometer over an urban site of Beijing, China. Continuous data have been processed over a two-year period, and inversion products, including aerosol optical depth (AOD), Ångström exponent (α), volumes of different aerosol particle size distributions, and single-scattering albedos (SSA), have been analyzed. AOD values were found to vary from 0.11 (5th percentile) to 1.14 (95th percentile) with a median of 0.34 at 500 nm, and the maximum and minimum seasonal α values in Beijing were 1.05 ± 0.36 in summer and 0.82 ± 0.39 in spring. SSA values are higher in summer and spring with a similar value of 0.96 ± 0.03, but lower in winter with a value of 0.93 ± 0.04 at 500 nm. Aerosol particles in Beijing clearly demonstrated bimodal size distributions throughout the year: there were coarser particles in spring and finer particles in summer. The α values increased with AOD, indicating that fine particles play an important role in the optical properties of aerosols in Beijing. Dust type aerosol occurrence accounted for 4.1 %, 5.1 %, 0.5 %, and 1.2 % of all measurements data in spring, summer, autumn, and winter, respectively, according to the dust criteria threshold (α < 0.47 and SSA400 nm - SSA1020 nm < 0.018).

【 授权许可】

Unknown