GESAMP Reports and Studies No. 97
GAW Report No. 238
The magnitude and impacts of anthropogenic atmospheric nitrogen inputs to the ocean
The present global modelling study of the Nr atmospheric cycle and Nr deposition to the ocean is the first that evaluates past, present and future Nr atmospheric deposition accounting for ON primary sources as well as for secondary ON chemical formation as a N-dependent process. While the total Nr deposition to the ocean is not expected to change significantly by 2050, the relative importance of oxidized and reduced N is expected to change, with an increasing proportion of ammonium compared to nitrate, resulting from more efficient controls on terrestrial emissions of nitrogen oxides (NOx) compared to ammonia. This would result in a change in the acidity of the atmospheric deposition.