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Post-Doctoral Fellowships
Characterization of Urban to Neighborhood Scale Air Pollutant and Human Exposure
using a Comprehensive Array of Fixed and Mobile Measurement Platforms
The complex behavior of primary and secondary air pollutants is a major challenge when
evaluating human exposure to air pollution. While primary pollutants vary in time and space
by the heterogeneity of emission sources, secondary pollutants also depend on the non-linear
reactions between the former and both depend heavily on meteorology. Moreover, in order to
fully understand the effect of the mix of pollutants on human health a better understanding of
the multiple constituents and their interrelations is needed. These challenges require the use
of multiple sources of information regarding the spatio-temporal variability of air pollutants,
including a variety of measurement methods and models.
The Border Air Quality and Meteorology Study (BAQS-Met) field campaign examined the
complexity of various processes in uencing summertime ozone levels in the southern Great Lakes
region of North America. Results from the eld campaign were examined with respect to land-lake
differences and local meteorology using a large array of ground-based measurements, aircraft data,
and simulation results from a high resolution regional air quality model. Results show that the
lakes act as a reservoir layer for ozone at night, which could cause elevated ozone levels over land
during the day at the lake breeze flow.
The Montreal mobile lab measurements campaign in 2009 examined the feasibility of deploying a
heavily instrumented mobile lab for characterizing air pollutants’ spatial patterns and examined
multi-pollutants’ concentrations and interrelationships at the intra-urban scale. Comparison of
the mobile lab averages to the adjacent air quality monitoring network stations to evaluate their
representativeness showed that they were in reasonable agreement with the annual averages at
the monitoring sites. This comparison provided some evidence that, through the deployment
approach, the mobile lab is able to capture the main features of the average spatial patterns. The
findings also indicate that the multi-pollutant mix varies considerably throughout the city, both in
time and in space, therefore no single pollutant can be a perfect proxy measure for the entire mix
under all circumstances. However, based on overall average spatial correlations with the suite of
pollutants measured, nitrogen oxide species appeared to be the best available indicators of spatial
variation in exposure to the outdoor urban air pollutant mixture.
Research publications
(1)
Levy, I., Makar, P.A., Sills, D.M.L., Zhang, J., Hayden, K.L., Mihele, C., Narayan, J., Moran, M.D., Sjostedt, S., &
Brook, J.R. (2010). Unraveling the complex local-scale flows influencing ozone patterns in the southern Great Lakes
of North America.
Atmospheric Chemistry and Physics, 10
(22), 10895-10915.
(2)
Makar, P.A., Zhang, J., Gong, W., Stroud, C., Sills, D.M.L., Hayden, K.L., Brook, J.R., Levy, I., Mihele, C., Moran,
M.D., Tarasick, D.W., He, H., & Plummer, D. (2010). Mass tracking for chemical analysis: The causes of ozone
formation in southern Ontario during BAQS-Met 2007.
Atmospheric Chemistry and Physics, 10
(22), 11151-11173.
(3)
Sills, D.M.L., Brook, J.R., Levy, I., Makar, P.A., Zhang, J., & Taylor, P.A. (2011). Lake breezes in the southern Great
Lakes region and their influence during BAQS-Met 2007.
Atmospheric Chemistry and Physics, 11
(15), 7955-7973.
(4)
Dayan, U., Tubi, A., & Levy, I. (2012). On the importance of synoptic classification methods with respect to
environmental phenomena.
International Journal of Climatology, 32
(5), 681-694.
(5)
Levy, I. (2013). A national day with near zero emissions and its effect on primary and secondary pollutants.
Atmospheric Environment, 77
, 202–212.
(6)
Levy, I., Mihele, C., Lu, G., Narayan, J., & Brook, J.R. (2014). Evaluating multipollutant exposure and urban
air quality: Pollutant interrelationships, neighborhood variability, and nitrogen dioxide as a proxy pollutant.
Environmental Health Perspectives, 122
, 65-72.
(7)
Levy, I., Mihele, C., Lu, G., Narayan, J., Hilker, N., & Brook, J.R. (2014). Elucidating multipollutant exposure across a
complex metropolitan area by systematic deployment of a mobile laboratory.
Atmospheric Chemistry and Physics, 14
, 1-21.
Fellow
Ilan Levy
Environment Canada
Supervisor
Jeffrey Brook
2008-2010