Pollution today has become both an important social and economic factor in American life, having been linked to deleterious effects on health and ecological systems. Yet little is known about how emissions spreading across the mid-Atlantic and Northeastern states are affected by the weather. For instance, are high pollution events in Philadelphia a result of emissions traveling along a coherent path, or are they affected by multiple parcel pathways from disparate locations? In order to discover answers to these and other questions, data from a combination of criteria gas analyzers, historical regional emissions data, and back trajectories, were incorporated into advanced modeling software (ArcGIS) to study haze and pollution events in Philadelphia. HYSPLIT 48-hour back trajectories were mapped in hourly intervals giving the location of air parcels terminating at three specific heights. Combined with (EPA) emission data, GIS was used to display air parcels on their way to Philadelphia traveling through weak and intense concentrations of SO2 and NOX. Our research focuses on the path the air parcel travels through these regions of varying trace gas concentrations, and their affect on the local concentrations observed in Philadelphia.

We identified a series of pollution events by averaging SO2 and NOX concentrations from criteria gas measurements in Philadelphia. Combining our GIS output with these events, we explored whether the events could have been predicted. The results of our research are shown in this poster presentation. Further research could tap into the 3D Analyst extension of GIS. This powerful three-dimensional program has capabilities which would provide a better understanding of how emissions are transported through all levels of the atmosphere.