An atmospheric selenium budget for the region 30° N to 90° N

Using a mass balance approach, an atmospheric selenium budget for the region 30° N-90° N has been constructed. The atmosphere was assigned four different aerosol burdens corresponding to mean selenium aerosol concentrations in urban, intermediate (rural). rernote/continental, and oceanic air. The budget calculations indicate that nearly all atmospheric selenium originates from anthropogenic emissions and biological activity in terrestrial and marine ecosystems. After comparing the sources of selenium to those of sulphur it is concluded that there are many similarities in their atmospheric cycling, but that there are also important differences.