Slide 30 of 31
Notes:
Back trajectories for several of the NEPART sites on 8/28/92 were provided by Bret Schichtel of CAPITA using the CAPITA Monte Carlo model. The NEPART network did not measure aerosol acidity directly; however an indirect estimate of acidity (shown as black bars) is occasionally possible through comparison of elemental sulfur and hydrogen measurements from the NEPART filters. The estimated acidity levels at several NEPART sites on 8/28/92 were the highest ever observed in the 1989-93 period of NEPART operation.
Unlike the southern Canadian sites, New England was still experiencing flows fro the Midwestern US at this time. Note however that the (blue) trajectories - arriving at the Quabbin, MA site (with maximum fine mass sulfate and acidity) have passed over Midwestern source areas, but have also stagnated more recently over over Northeast coast metropolitan areas.
Here, as with the Kejimkujic site a few days earlier, we appear to have a combined influence from distant and relatively nearby sources.
Effective management of transboundary air resources requires a better understanding of the complex influences of local, regional and more distant sources. This understanding and subsequent development of management strategies will continue to be compromised so long as our data (unlike our pollution) does not flow freely across our common border.
