Balances of oxidized sulfur and nitrogen over the former Soviet Union territory

Detailed sulfur and nitrogen emission inventories have recently been constructed for the former Soviet Union (FSU) territory, with 1 × 1 degree resolution (Ryaboshapkoet al., 1996, Report CM-89, International Meteorological Institute in Stockholm, Department of Meteorology, Stockholm University). In this study, observations of sulfur and nitrogen compounds in air and in precipitation during 1980–1990 were compiled and deposition fluxes calculated. A three-dimensional (3D) global tracer transport model (MOGUNTIA) of oxidized sulfur and nitrogen was used to check the consistency between the observations and the emission data and to calculate the balances of these species for the FSU area. Distributions of the wet deposition fluxes of these species are presented and compared with observations. Important gaps in knowledge are identified and recommendations are made to improve the monitoring network for the former Soviet Union.