TRENDS IN WET AND DRY DEPOSITION OF SULFUR IN THE UNITED-KINGDOM

UK data on sulphur deposition trends between the 1960's and 1990's are presented. Long term data sets of sulphur dioxide (SO2) concentration s at two sites have been analysed and dry deposition determined using a resistance model. Wet deposition has been calculated from non-marine sulphate concentration and rainfall fields for 1978-80 and 1989-93. T hese maps have been interpolated and corrected for seeder feeder enhan cement. The wet deposition of sulphur declined by about 43 % between 1 979 and 1993 whereas emissions of sulphur declined by about 32 %. An i ndication of the trends in sulphur dry deposition is provided by data from Eskdalemuir, a site in southern Scotland where wet deposition and SO, concentration have been measured since 1979. Dry deposition at Es kdalemuir has decreased by 70 % and wet deposition by 48 %. Hence, whi le wet deposition has responded approximately linearly with the declin e in UK emissions of sulphur dioxide, dry deposition has declined at t wice the rate of decline in UK emissions.