Atmospheric trace metal concentrations at Norwegian background sites during 25 years and its relation to European emissions

A comprehensive time trend analysis for a 25-years data set on trace metal concentrations from Norwegian monitoring stations have been carried out. At the Birkenes station, one of the stations with longest data record and located at a region in Southern Norway which is mostly affected by atmospheric long-range transport, the reductions have been 97%, 95% and 70% for, respectively, Pb, Cd and Zn in precipitation in the period 1980–2005. Changes in pollution levels are mainly due to changes in emission data and transboundary pollution. A comparison of the changes in monitoring data with changes in the anthropogenic emissions for Europe and Norway have therefore been carried out especially for Pb and Cd.