Problems of Modelling the Long-Range Transport of Reduced Nitrogen
As negotiations on a new sulphur protocol under the UN Economic Commission for Europe reach an advanced stage, increasing attention is being paid to the contribution of nitrogen compounds to acidification. In this context European emissions of nitrogen as ammonia (estimated at almost 8 million tonnes of N over the EMEP map area- EMEP 1993), originating mainly from livestock, are comparable with those as NOx (7 million tonnes as N over the same map area). However as a reactive gas emitted at or near ground level from a distribution of sources, there are special problems in modelling the subsequent dispersion and atmospheric transport out to long distances. There are also large uncertainties about the nature and magnitude of emissions, and the interaction of ammonia with other atmospheric species. This paper illustrates some of these difficulties by application of a Lagrangian model TERN (Transport over Europe of Reduced Nitorgen) to selected episodes.
KeywordsCombustion Europe Hydrocarbon Acidity Sewage
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- Kruse M and Bell JNB (1987) Ammonia emissions and their role in acid deposition. Atmospheric Environment 19(1), p 99–111Google Scholar
- ApSimon HM, Barker B M and Kayin S Modelling studies of the atmospheric release and transport of ammonia - applications of the TERN model to an EMEP site in eastern Engand in anticyclonic episodes.Atmospheric Environment-in press.Google Scholar
- EMEP (1993) Calculated budgets for air borne acidifying components in Europe. EMEP/MSC-W Report 1/93Google Scholar
- Kayin S (1993) Wet deposition in convective storms and effects on transboundary air pollution. Ph D thesis University of London.Google Scholar
- Kruse-Plass M, Barker B M and ApSimon HM (1993) A modelling study of the effect of ammonia on in-cloud oxidation and deposition of sulphur. Atmospheric Environment 27A No2 p223–234.Google Scholar