Background precipitation chemistry monitoring in the Soviet Union.

An overview is given of the precipitation chemistry field and laboratory programs of the former U.S.S.R. World Meteorological Organization Background Air Pollution Monitoring Program (WMO BAPMoN). Field and laboratory procedures are discussed, siting criteria are examined, station histories are documented, and four Soviet quality assurance techniques are discussed. Comparison of data from three Soviet BAPMoN stations with data from three U.S. BAPMoN stations indicate that sulfate concentrations are comparable but that U.S. samples are typically much more acidic. Soviet samples tend to have higher concentrations of cations of soil origin and higher concentrations of ammonium.