Characteristics of snowpack chemistry on the coastal region in the northwestern Greenland Ice Sheet facing the North Water

Abstract. In the North Water, the opening of sea ice due to polynya formation influences the surrounding water and aerosol circulation. We conducted glaciological observations from seacoast to inland on the western side of Prudhoe Land, which is located in the northwestern Greenland Ice Sheet close to the North Water, to elucidate water and aerosol circulation around the North Water. The spatial variations in δ¹⁸O and chemical substances in surface snow showed that water vapor and aerosols were directly transported from the southern North Water to northern inland of areas on the western side of Prudhoe Land. Unlike the inland area of the Greenland Ice Sheet, the snowpack on the western side of Prudhoe Land contained signals of ocean biological and sea ice conditions in the North Water. The methanesulfonic acid identified in the summer snowpack originated from a phytoplankton bloom in the North Water. NH₄⁺ in autumn–winter snowpacks could originate from ammonia gas emissions from organisms in the North Water. The Na⁺, Cl⁻, K⁺, Mg²⁺, SO₄²⁻, and Ca²⁺ concentrations in the snowpack rapidly increased in winter, which could be attributed to the emission of frost flowers from the newly formed sea ice surface into the atmosphere due to intense storm activity in the North Water. We suggest that the chemical substances identified in the snowpack or ice core from the western side of Prudhoe Land can be used to better understand past changes in ocean biological and sea ice conditions in the North Water.