Manure management in Norway is a source of emissions to air of ammonia (NH3), nitrous oxide (N2O), nitric oxide (NO) and nitrogen (in the form of N2). The Norwegian model for calculating the agricultural nitrogen emissions to atmosphere is used for reporting for the Norwegian emission inventory. The main aim of the project was to revise and expand the models which have been used in the past by Norway for calculating the agricultural nitrogen emissions to atmosphere.
The main manure management and use phases considered in the model are (i) animal housing, (ii) manure storage, and (iii) manure spreading on agricultural land, plus (iv) deposition as a result of animal grazing. The revised Norwegian model, which was developed by Carbon Limits in close cooperation with the Norwegian Environment Agency (Miljødirektoratet) and Statistics Norway (SSB), calculates direct emissions of N2O, NO and N2 in addition to calculating emissions of NH3.