Description and Intercomparison of Techniques to measure N and S compounds in the Western Atlantic Ocean Experiment

The data set of N and S compound measurements from WATOX-85 has been examined in detail to assess that data quality and suitability for use in addressing the goals of the Western Atlantic Ocean Experiment. Accuracy estimates for particulate SO42− and NO3−, SO2 and HNO3 have been made on the basis of the investigators' estimates and the results of intercomparisons. Intercomparisons of ground-based particulate SO42− and all filter SO2 and HNO3 measurements show them to be consistent with the 20% accuracies quoted by the investigators. Ground-based particulate NO3− and aircraft particulate SO42− show inconsistencies such that the accuracies can be no better than 28% and the aircraft particulate NO3 has an accuracy of no better than 60%.