Aerosol pH and regime transition of sulfate formation in aerosol water during winter haze events in northern China

Wei Tao1, Hang Su1, Guangjie Zheng2, Jiandong Wang1, Lixia Liu1, Chao Wei1, Meng Li1, Qiang Zhang3, Ulrich Poeschl1 and Yafang Cheng1, (1)Max Planck Institute for Chemistry, Multiphase Chemistry Department, Mainz, Germany, (2)Washington University in St Louis, St. Louis, United States, (3)Tsinghua University, Beijing, China