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Modelling Concentrations and Deposition of Long Range Air Pollutants - AQ02514

Summary of contract CPEA 34

Modelling the Deposition and Concentration of Long Range Air Pollutants

This contract will make use of the Fine Resolution Atmospheric Multi-pollutant Exchange computer model FRAME ( The model is designed to numerically simulate the emissions of pollutant gases, their dispersion, transport and chemical transformation in the atmosphere as well as deposition to surface vegetation by both dry deposition and rainfall in the British Isles.

In particular the work will focus on the fate of SO2 (emitted mostly from industrial combustion), NOx (emitted primarily from vehicle exhausts) and NH3 (associated with agricultural emissions from livestock and fertiliser application). These three species all contribute to acid deposition, which results in damage to terrestrial and freshwater ecosystems. NOx and NH3 emissions contribute to eutrophication, the nitrogen enrichment of soils, which can result in a change in the composition of plant species in favour of nitrogen-loving plants. The results from the FRAME model will be used to make calculations of the exceedance of critical loads (the levels above which ecosystem damage may occur) for acidic deposition and nutrient nitrogen deposition.
Project Documents
• Final Report : Modelling Concentrations and Deposition of Long Range Air Pollutants   (5237k)
Time-Scale and Cost
From: 2002

To: 2005

Cost: £164,984
Contractor / Funded Organisations
Centre for Ecology and Hydrology
Air Pollution              
Environmental Protection              
Fields of Study
Air Quality