Long distance transport of pollen to Greenland

Four pollen traps were recently placed at coastal sites in East and West Greenland in order to assess long distance transport of pollen to the Arctic domain. By identifying potential vegetation source areas associated with air mass pathways we were able to produce the first detailed record of pollen transport from eastern North America to Narsarsuaq, southern Greenland. The record is based on observations and on a transport and dispersion model used to calculate back trajectories of the air masses. The evidence points to the pollen being transported northward by the air mass over Newfoundland and the Labrador Sea before reaching Narsarsuaq. At this point, the air mass was at an altitude of 3000 m. Deposition of pollen grains occurred with downward air movements associated with a 0.5 mm/h rain. The source areas for these pollen grains differ from those of dust and certain other aerosols that reach the summit of the Greenland Ice Sheet. The results demonstrate the need for continued maintenance and analysis of the Greenland pollen trap data in order to improve our understanding of atmospheric circulation and transport to high northern latitudes.