HR: 12:10h
AN: A72B-06    [Abstracts]
TI: Ground and Satellite Observation of NO₂ in Southwestern Ontario During the 2007 BAQS-met Campaign
AU: * Lee, C J
EM: colinj.lee@utoronto.ca
AF: University of Toronto, 200 College Street, Toronto, ONT M5S 3E5, Canada
AU: Brook, J R
EM: Jeff.Brook@ec.gc.ca
AF: Environment Canada, 4905 Dufferin St., Toronto, ONT M3H 5T4, Canada
AU: Evans, G
EM: greg.evans@utoronto.ca
AF: University of Toronto, 200 College Street, Toronto, ONT M5S 3E5, Canada
AU: Martin, R
EM: randall.martin@dal.ca
AF: Dalhousie University, 6300 Coburg Road, Halifax, NS B3H 4R2, Canada
AU: van Donkelaar, A
EM: Aaron.van.Donkelaar@dal.ca
AF: Dalhousie University, 6300 Coburg Road, Halifax, NS B3H 4R2, Canada
AU: Lamsal, L
EM: lok.lamsal@fizz.phys.dal.ca
AF: Dalhousie University, 6300 Coburg Road, Halifax, NS B3H 4R2, Canada
AB: Examining spatial and temporal variability in air pollutant concentrations provides insight into sources, atmospheric transport patterns and potential impacts. NO₂ is an important pollutant to track because it is strongly linked to combustion, the cycle of photochemical oxidants and the fate of anthropogenic pollutants from local to regional scales. Various measurement strategies offer spatial or temporal resolution for NO₂, but combined highly-resolved spatiotemporal evaluations are rare. Chemiluminescence analyzers can provide high time resolution NO₂ point measurements but are expensive. Passive monitors can be deployed in multiple locations simultaneously, due to their lower cost, but provide time-averaged concentration measurements. The Ozone Monitoring Instrument aboard the EOS Aura satellite allows NO₂ column density snapshots of the troposphere to be taken with daily frequency in most locations at a maximum spatial resolution of 13 × 24 km². Tropospheric NO₂ column densities derived from OMI have been shown to be a useful data source in analyzing ground level air quality, however there have been relatively few detailed evaluations of the spatial patterns revealed by OMI over areas of transition from high to low concentrations. During the Border Air Quality and Meteorology study of 2007, surface NO₂ was measured in Southwestern Ontario for a period of almost three months in June, July and August. High time resolution data were obtained at 5 sites while two week integrated concentrations were measured through a network of 18 passive monitors. Emissions from the urban centres of Detroit, MI and Windsor, ON impacted the monitoring sites to different extents. This region was chosen because of the influence of the Great Lakes on local meteorology coupled with the impacts of local and transboundary sources on air quality. The spatiotemporal trends in NO₂ will be presented. These data will be used to explore the capabilities and limitations of the satellite as an observer of ground based concentrations and how different data interpretation strategies affect those limitations. The relationship between the spatial resolution obtainable through the satellite data and the degree of temporal averaging will be discussed.
DE: 3307 Boundary layer processes
DE: 3329 Mesoscale meteorology
DE: 3360 Remote sensing
DE: 3394 Instruments and techniques
SC: Atmospheric Sciences [A]
MN: 2009 Joint Assembly