Measurements of nitrogen dioxide in Greenland using Palmes diffusion tubes

Measurements of nitrogen dioxide using the Palmes diffusion tubes in Uumman naq, Aasiaat, and Nuuk, all located along the west-coast of Greenland, have demonstrated that the levels of pollution at the mast heavily impacted sit es: are comparable to levels in much larger towns in Denmark. The highest c oncentrations were, in general, observed near sites influenced by cal traff ic (peak concentrations of up to 16 ppbv), medium concentrations were obser ved in the residential areas (2-6 ppbv). and very low levels were found at the background locations in the town outskirts (1-2 ppbv). Observations of nitrogen dioxide concentrations less than 0.1 ppbv tit a remote site, Akia, 25 km from Nuuk, indicate that, compared to local sources, long-range tran sport of nitrogen dioxide is not important in western Greenland.