An intercomparison of models used to simulate the short range atmospheric dispersion and deposition of agricultural ammonia emissions

Abstract

Ammonia (NH3) emitted into the atmosphere from agricultural sources can have an impact on nearby sensitive ecosystems either through elevated ambient concentrations or dry/wet deposition to vegetation and soil surfaces. Environmental impact assessments are often carried out using short-range atmospheric dispersion models to estimate mean annual atmospheric concentrations and total annual deposition of NH3 at the ecosystem location. A range of different atmospheric dispersion models are used for these assessments depending on the location and experience of the assessors and have not, until now, been compared for these types of assessments. This poster compares and validates concentration predictions of four commonly used models (ADMS v4.11, AERMOD v070262, LADD3 and OPS-st4,5) for dispersion from agricultural sources using hypothetical and real case studies