A 800 year record of nitrate from the Lomonosovfonna ice core, Svalbard

Detailed chemical analysis of the 122 m, relatively high-altitude and low-melt Lomonosovfonna ice core provides the best-dated record of nitrate from Svalbard. A very significant non-linear trend present in the record shows: (a) a rise in concentrations from the 12th to the mid-16th century, (b) reasonably stable concentrations until the mid-19th century, (c) a rise in concentrations into the 20th century, with (d) a rapid rise in the 1950s and (e) a decrease after the mid-1980s. Nitrate is well correlated with ammonium before 1920 and after 1960 but not in the intervening period. The correlation between ammonium and nitrate concentrations indicates that ammonium nitrate (NH₄NO₃) has been common at Lomonosovfonna. There are also places in the core where nitrate is very closely associated with calcium.