Focus on emission factors: a sensitivity analysis of ammonia emission modelling in the Netherlands

A modelling system is used to evaluate policy aiming at reducing ammonia emissions from Dutch Agriculture. This system is based on calculations with the “Manure Model” developed by the Agricultural Economics Research Institute. The goal of this paper is to identify the effect on ammonia emissions of uncertainties, with respect to (1) emission factors and (2) the implementation of techniques to reduce ammonia emissions. The paper also aims to make recommendations on how to improve the modelling system. A sensitivity analysis is carried out for the “Manure Model” to identify the effect of the uncertainties. Results show that uncertainty regarding emission factors is more important for the level of ammonia emission than uncertainty regarding the use of techniques to reduce emissions; it is therefore proposed that emission factors should receive more attention. Most important in this respect are emission factors for dairy cattle housing and techniques for applying animal manure.