An exceedance score for the assessment of the impact of nitrogen deposition on habitats in the UK. (April 2022)

• Record Type: Journal Article
• Authors: Woodward, H.; Oxley, T.; Rowe, E.C.; Dore, A.J.; ApSimon, H.
• Is Part Of: Environmental modelling & software. Volume 150(2022)
• Publication Date: 2022-04
• Subjects: Nitrogen deposition -- Uncertainty -- Critical loads -- Eutrophication -- Integrated assessment modelling; Environmental monitoring -- Computer programs -- Periodicals; Ecology -- Computer simulation -- Periodicals; Digital computer simulation -- Periodicals; Computer software -- Periodicals; Environmental Monitoring -- Periodicals; Computer Simulation -- Periodicals; Environnement -- Surveillance -- Logiciels -- Périodiques; Écologie -- Simulation, Méthodes de -- Périodiques; Simulation par ordinateur -- Périodiques; Logiciels -- Périodiques; Computer software; Digital computer simulation; Ecology -- Computer simulation; Environmental monitoring -- Computer programs; Periodicals; Electronic journals; 363.70015118
• DOI: 10.1016/j.envsoft.2022.105355
• Languages: English
• ISSNs: 1364-8152

Abstract

Abstract: Large areas of nitrogen-sensitive habitats are currently estimated to be in exceedance of their critical loads (CLs) as indicators for protection from nitrogen deposition. In the UK, deposition estimates from the semi-empirical Concentration Based Estimated Deposition (CBED) model are used for official reporting of current exceedances. The UK Integrated Assessment Model (UKIAM) framework is designed to provide future projections of concentrations and deposition due to projected changes in emissions. UKIAM has been extended to provide alternative deposition estimates aligned with those of CBED, and the results combined with the range in habitat CL values to create an exceedance score, leading to a probabilistic evaluation of CL exceedances. The utility of the method is demonstrated by analysing a series of hypothetical scenarios. It is shown that NH3 mitigation is likely to be four times more effective in reducing CL exceedances in the UK than the mitigation of NOx emissions. Highlights: A new probabilistic approach for the evaluation of critical load exceedances in the UK. Provides a more stable indicator for reductions in eutrophication critical loads. In the UK the abatement of NH3­ emissions is 4x more effective at reducing CL exceedances than the abatement of NOx . NH3 and NOx emission reductions of 50% required to restore 75% of UK sensitive habitat area to a favourable condition.