1. a State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University , Beijing, 100101, PR China
2. b Graduate School of the Chinese Academy of Sciences , Beijing, 100049, PR China
3. c Centre for Atmosphere Watch and Services, Chinese Academy of Meteorological Sciences, China Meteorological Administration , Beijing, 100081, PR China
4. d Ziyuyuan Environ-Protection Limited Company of Science and Technology , Beijing, 102200, PR China