AAAR 35th Annual Conference October 17 - October 21, 2016 Oregon Convention Center Portland, Oregon, USA
Abstract View
Investigation of Wintertime Aerosol Chemistry Using Single Particle Mass Spectrometry
RYAN COOK, Matthew Gunsch, Katheryn Kolesar, Kerri Pratt, University of Michigan
Abstract Number: 253 Working Group: Urban Aerosols
Abstract Atmospheric aerosols are known to have negative human health impacts and thus are regulated by the Clean Air Act. Most aerosol measurements have focused on summertime; however, wintertime air quality is often influenced by different aerosol sources. In particular, few studies have investigated wintertime air quality in the urban Midwestern US environment, which is expected to be influenced by both local and long-range transported particles. During February-March 2016, size-resolved chemical composition of individual atmospheric particles ranging from 0.1-1.5 microns in diameter was measured in real-time using an aerosol time-of-flight mass spectrometer (ATOFMS) in Ann Arbor, Michigan. Chemically-resolved particle number concentrations were obtained through coupling with a scanning mobility particle sizer and an aerodynamic particle sizer. The main particle types identified were primarily biomass burning from residential heating and organic carbon-elemental carbon particles from vehicular emissions. Many particles were internally mixed with sulfate, nitrate, and ammonium, evidence of atmospheric aging processes. Contributions from mineral dust, metal-rich particles, and road salt were also observed. These results will be useful in improving our understanding and prediction of air quality in wintertime urban environments.