Refinement, Calibration, and Fields Studies Involving Transportable Aerosol Time-of-Flight Mass Spectrometers;Final rept

摘要

Recently developed transportable aerosol time-of-flight mass spectrometry (ATOFMS) instruments and a lab-based ATOFMS instrument were used for the first long-term continuous monitoring study of the aerodynamic size and chemical composition of individual aerosol particles. This study was part of the 1997 Southern California Ozone Study-North American Research Strategy for Tropospheric Ozone (SCOS97-NARSTO) Aerosol Program. The spatial and temporal variability of aerosol particles were studied, examining the effects of transport from regions with 'fresh' emissions (i.e. Los Angeles, CA) to areas of increasing pollution levels (i.e. Riverside, CA). A variety of strategies were developed to provide a picture of the particle sources and atmospheric processes occurring for particles in different regions. Procedures were developed to scale the ATOFMS data into atmospherically representative total, nitrate, and ammonium mass concentrations. Once calibrated, the ATOFMS data were plotted over time to study how particles vary over time in Southern California. The instruments developed as part of this project will continue to be used in studies throughout California to provide a more complete understanding of the sources of particles as well as their spatial and temporal variability due to atmospheric transformations.