Measurements of atmospheric sulfur dioxide performed during the Swedish expedition “Ymer 80” in the Arctic are presented. Wet chemical filter sampling and subsequent chemiluminescence analysis enabled detection in the low pptv range. SO2 mixing ratios between 5 pptv and 100 pptv were measured. SO2 values over the closed ice sheet were usually lower than over the open ocean. Possible source and sink mechanisms are discussed. The influence of atmospheric transport is shown by trajectory analysis and helicopter ascents.