New Google® tools for mapping including Google Maps and Google Earth make it possible to dynamically present a combination of measured air quality values and their associated trajectories as well as miscellaneous additional information such as precipitation and known emission locations and strengths. This paper illustrates an open-source system created using PHP and MySQL that can be used for research or education to explore the relationships between observed concentrations and the meteorological conditions at and upwind of a measurement location. Trajectories can be displayed in six-hour ensembles over the period of measurement or as visualized probability of transport. Trajectories are viewed in ensemble at http://www.qtba.org/ as sample days are selected. Individual trajectories can be selected from the ensemble and viewed as a fly-through in Google Earth using dynamically generated .kmz files.

This tool has been designed as a resource for Quantitative Transport Bias Analysis (QTBA) receptor modeling. QTBA identifies the spatial bias in transport for measured species. Its use with multiple concurrent receptors offers a method for estimating source locations and relative source strength.