Measurements of atmospheric and snow mixing ratios of nitrates and nitrites and their fluxes above the snow surface were made during two intensive campaigns during spring time 2001 at Ny-Ålesund, Svalbard as part of the EU project&nbsp; &quot;`The NItrogen Cycle and Effects on the oxidation of atmospheric trace species at high latitudes" (NICE).<br> <br> At this coastal site close to the unseasonably unfrozen fjord, of the measured nitrogen species, only HNO₃ showed a significant flux on to the snow surface; a mean deposition of -8.7 nmol h^-1 m^-2 was observed in late April / early May 2001. These fluxes may be due to the reaction of HNO₃ with sea salt, and especially NaCl, or may be simply uptake of HNO₃ by ice, which is alkaline because of the sea salt in our marine environment. During snowfall periods dry deposition of HNO₃ may contribute up to 10% of the N budget in the snow; however, the main source for N is wet deposition in falling snow.<br> <br> The surface snow at Ny-Ålesund showed very complex stratigraphy; the NO₃^- mixing ratio in snow varied between 65 and 520 ng g^-1, the total NO₃^- content of the snowpack was on the order of 2700 ng cm^-2. In comparison the atmospheric boundary layer column showed a NO₃^- content of only 8 ng cm^-2. The limited exchange, however, between the snow and the atmosphere was attributed to low mobility of NO₃^- in the observed snow.<br> <br> Contrary to other Arctic sites (i.e. Alert, Nunavut or Summit, Greenland) deposition of sea salt and crustal aerosols in this marine environment made the surface snow alkaline; snow NO₃^- was associated with heavier cations and was not readily available for physical exchange or photochemical reactions.