Spatial Source Contributions Identification of Acid Rain over the Yangtze River Delta Using a Variety of Methods
GE Bao-Zhu;LIU Ying;CHEN Huan-Sheng;PAN Xiao-Le;WANG Zi-Fa;State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences;Laboratory for Climate Studies, National Climate Center, China Meteorological Administration;Research institute for applied mechanics/Kyushu university;
The source-receptor relation of wet deposition has been a continuous issue in studies of regional environmental pollution over the past two decades. In the absence of direct observational evidence, the problem is difficult to solve—a topic of broad international debate since the turn of the present century. In the present study, a variety of methods focused on the sources of the wet deposition of acidic substances, like sulfate and nitrate, were used to investigate the precipitation chemistry over the Yangtze River Delta(YRD) during 2007. Back-trajectory analysis associated with the observation data and a source tracing method coupled with the Nested Air Quality Prediction Modeling System(NAQPMS) are proved to be effective methods for investigating the sources of wet deposition over the YRD. Comparison among the back-trajectory, footprint, and NAQPMS results shows good consistency, both qualitatively and quantitatively. The most important contributor to acidic substances in the YRD, as well as heavy acid rain over the region, is the anthropogenic pollution from East China, which accounts for more than 70%.