The “Beijing City Air Pollution Observation

ABSTRACT. The Beijing City Air Pollution Observation Experiment (BECAPEX) is the most comprehensive field program carried out to date to characterize the air pollution sources and processes in and around Beijing City. A key issue the BECAPEX experiment addresses is whether the air quality in the Beijing Metropolitan area (BMA) can meet the standards in 2008 set by the Beijing Olympic Organizing Committee by controlling the emissions within BMA. Observations from BECAPEX revealed that the air quality BMA is a regional problem. Although reduction of emissions within BMA can generally improve its air quality, under certain weather conditions, transports by local head island circulation, synoptic and large-scale winds can carry pollutants from regions to the south and east of the BMA. These multi-scale transports play a crucial role in determining the air quality in the BMA. Thus, in order to properly address its air pollution issue, Beijing and its neighboring region must be considered as an integrated system, where pollution control strategies must be formulated synergistically