Real-time, single-particle measurements of ambient aerosols in Shanghai

Abstract

As one of the major components of the earth’s atmosphere, airborne particulate matter (or aerosol) has strong effects on air quality, regional and global climate, and human health. In ambient atmosphere, the different sources and complex evolutionary history of aerosol particles make the study of their chemical and physical properties extremely challenging. The invention of an online single-particle aerosol mass spectrometer provides a powerful technique to determine the size and chemical composition of individual aerosol particles in real time. We deployed an aerosol time-of-flight mass spectrometer (ATOFMS) to carry out single particle measurement in the urban area of Shanghai in the past few years. In this review paper, we summarize our recent work on the identification of particle type, mixing state and aging process, and the application of the individual particle information to the source apportionment of primary aerosol, and the investigation of the formation mechanism of secondary aerosol in Shanghai. The special capabilities of single particle mass spectrometry are proven essential to these studies. Multi-functional technique combinations of ATOFMS with other state-of-art aerosol instruments are also discussed for future studies.