AAAR 32nd Annual Conference
September 30 - October 4, 2013
Oregon Convention Center
Portland, Oregon, USA
Abstract View
The Spatial Characterization of Ultrafine Particles in Toronto (SCULPT) Study: The Winter Campaign
KELLY SABALIAUSKAS, Ezzat Jaroudi, Cheol-Heon Jeong, Jon M Wang, Natalia Mykhaylova, Krystal J. Godri-Pollitt, Jill Kearney, Amanda Wheeler, Ryan Kulka, Hongyu You, Greg J. Evans, SOCAAR, University of Toronto
Abstract Number: 461 Working Group: Urban Aerosols
Abstract The Spatial Characterization of ULtrafine Particles in Toronto (SCULPT) Study is an ongoing investigation focused on the spatiotemporal variation of traffic related air pollutants (ultrafine particles (UFPs), black carbon (BC), NO$_2 and NO$_x) in Canada’s most populous city. A total of 22 residential field sites were selected based on their proximity to traffic and other geographical features such as parks, Lake Ontario, commercial areas, rail lines, and industrial areas. The 22 sites were dispersed between 4 and 45km away from a Central site.
The winter field deployment occurred between February 1st and March 10th 2013 and was divided into two phases each lasting two weeks (11 field sites operating simultaneously). Continuous measurements of UFPs with diameters >10nm and BC (measured by microaethalometer) were collected at each site. A variety of particle sizing and counting instruments were deployed to characterize UFP including a Fast Mobility Particle Sizer (Central Site), six Scanning Mobility Particle Sizers (various models), condensation particle counters and DiscMinis. Passive NO$_2 and NO$_x samples were collected at each residential field site and at the nearest major arterial roadway (44 sites).
A wide range of meteorological conditions were experienced in Toronto throughout the campaign including low temperatures, stagnant and fast moving air masses, and significant snowfall events. Preliminary results indicate that the residential field sites usually had lower particle number and BC concentrations than the downtown Central Site. However, BC concentrations exhibited less spatial variability than UFP (coefficient of divergence for UFP > BC). The diurnal behaviour observed at each residential site had different rush hour maximum times that varied due to their distance from the downtown core. UFP and BC concentrations were more homogeneous across the city during periods with stagnant air masses and when the city was impacted by long-range transport.