Abstract
Sulfate aerosols are ubiquitous in the troposphere and play important roles in air pollution and climate change. This article reviews the current status of automated, online analysis methods for mass concentrations of PM2.5 sulfate aerosols. The methods include a Particle-Into-Liquid sampler coupled with ion chromatography (PILS-IC), an Aerodyne aerosol mass spectrometer (AMS), a Thermo sulfate particle analyzer (SPA). Although they can achieve sufficiently high precision required for ambient measurements in many cases, routine calibration is one of the most critical issues that have not been fully addressed. A calibration protocol for the quality assurance of online analysis of mass concentrations of PM2.5 sulfate aerosols is proposed and discussed.
