Improved modelling of atmospheric ammonia over Denmark using the coupled modelling system DAMOS

[摘要] A local-scale Gaussian dispersion-deposition model (OML-DEP) has beencoupled to a regional chemistry-transport model (DEHM with a resolution ofapproximately 6 km × 6 km over Denmark) in the Danish Ammonia Modelling System,DAMOS. Thereby, it has been possible to model the distribution of ammoniaconcentrations and depositions on a spatial resolution down to 400 m × 400 mfor selected areas in Denmark. DAMOS has been validated against measuredconcentrations from the dense measuring network covering Denmark. Heremeasured data from 21 sites are included and the validation period covers2–5 years within the period 2005–2009. A standard time series analysis(using statistic parameters like correlation and bias) shows that the coupledmodel system captures the measured time series better than the regional-scale model alone. However, our study also shows that about 50% of themodelled concentration level at a given location originates from non-localemission sources. The local-scale model covers a domain of 16 km × 16 km, andof the locally released ammonia (NH₃) within this domain, oursimulations at five sites show that 14–27% of the locally (within 16 km × 16 km) emitted NH₃ also deposits locally. These results underline theimportance of including both high-resolution local-scale modelling ofNH₃ as well as the regional-scale component described by the regionalmodel. The DAMOS system can be used as a tool in environmental management inrelation to assessments of total nitrogen load of sensitive nature areas inintense agricultural regions. However, high spatio-temporal resolution ininput parameters like NH₃ emissions and land-use data is required.

[学科分类] 地球化学与岩石