Field investigation of water soluble ionic species in aerosols and the formation of fine sulfate and nitrate in the atmosphere

Abstract

Water soluble ionic species in PM₂.₅ play an important role in the climate forcing, heterogeneous chemistry, cloud formation as well as human health. In this study, the data of both one hour and twenty-four hour water soluble ions were obtained. These two types of data are important for interpreting the behaviors of ion species in the atmosphere. Secondly, this study was conducted in the megacities of China which has long been known for its severe air pollution caused by high concentrations of particulate matter. In addition, there is limited knowledge on the distribution of aerosols in suburban and/or rural areas and on the formation of secondary aerosols in China. Such knowledge is essential for evaluating the impact of a megacity's emission on regional air quality and climate. Thus, this study is valuable and important for the more in-depth understanding of the water soluble ion species as well as the current air pollution situation in China. The objectives of this study include the determination of the data accuracy and quality of the recently developed Ambient Ion Monitor (AIM). The field studies document the present levels of the water soluble ion species at different parts of China. This study also provides more in-depth analysis of the behaviors of ion species as well as the formation of fine sulfate and nitrate in the atmosphere. The comparison of the water soluble ion species in different parts of China was also made. Finally, the visibility problem in China was demonstrated.