The nitrogen in atmospheric deposition is, to a large extent, also related to agricultural emissions. In the last decade, the NOx and NH3 emissions in Europe declined mainly due to policies that enforced measures in transport, industries and the Nitrate directive (EEA, 2014). N deposition could be modelled (e. g. Banzhaf et al, 2015), the deposition can reach 10 kg(N) or 20 kg(N)/ha and more in Northwestern Europe. N deposition is not an indicator by itself but it can be used in other indicators since in some region, the N from atmospheric source is not negligible and can be taken into consideration when defining N fertiliser need or calculating N budgets.
The United Nations Economic Commission for Europe (UNECE) defined a network called Convention on Long-range Transboundary Air Pollution (CLRTAP) to reduce and monitor air quality and pollution in the region. A scientifically based and policy driven program under CLRTAP is the European Monitoring and Evaluation Program (EMEP), an international co-operation to solve transboundary air pollution problems by providing e. g. modelling results for monitoring and policy making. Results provided by EMEP show that in a majority of the EMEP sites a decreasing trend N deposition since 1990 is visible. Results can also be used as data input for composite indicators (EMEP, 2018).