An Assessment of Meteorological Effects on Air Quality in Windsor, Ontario, Canada - Sensitivity to Temporal Modeling Resolution

The HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory) model was used to study air quality in the City of Windsor (42.16 degrees N, 82.58 degrees W), Ontario, Canada. Two-day back trajectory simulations were conducted for the year of 2003 to investigate the regional transport of air pollutants. Trajectories were then characterized by air mass path direction and regions traversed, as dominant factors in regional transport of air pollutants, to assess meteorological effects on air quality in Windsor and provide initial identification of potential upwind pollution source regions. Statistical analysis was conducted to study whether the trajectory simulation results are sensitive to temporal modeling resolution of one, two, three and six simulations per week. It was found that HYSPLIT backward trajectory modeling can provide good quality and consistent results with a temporal resolution of two or three runs per week, comparable to a resolution of six runs per week. The HYSPLIT backward trajectory modeling and analysis methods presented can identify potential source regions of transboundary pollutants at practical temporal modeling resolutions. This is useful to communities and policy-makers developing public health policy.