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Monitoring and modelling trace-gas changes following FMD to reduce the uncertainities in agricultural emissions... - AM0116

There is currently substantial uncertainty in the effectiveness of measures to reduce emissions of agricultural trace gases, including ammonia (NH3), methane (CH4) and nitrous oxides (N2O). Since agricultural practices contribute to these emissions through a wide range of point and diffuse sources, the only effective way to assess pollution abatement policies is through monitoring air concentrations and, where relevant, deposition. However, there are still major uncertainties regarding the link between emissions, air concentrations and deposition. This has been shown, in particular, for ammonia in other European countries, where there was uncertainty in the changes following either abatement policies or sector activity changes.

The outbreak of Foot and Mouth Disease (FMD) in Great Britain in 2001 provides a major case study that could be used to test the relationship between agricultural emissions and concentrations of these trace gases. In this context, it is less important that FMD was the cause of change than the fact that an emission reduction has occurred which can be exploited to test the relationships.

Given the uncertainties in trace gas concentrations, both through their spatial and temporal variability, the contribution of non-agricultural sources and the scale of change, the project proposed will analyze the potential to use monitoring and modelling of trace gas concentrations to establish the link between changes in emissions and atmospheric concentrations. The work includes a combination of data assimilation on the changed sector activities, and atmospheric dispersion modelling at UK and regional scales to assess the expected changes. The project considers the monitoring methods available to detect change following the expected recovery in animal numbers. Given the precision of the measurements, the spatial and temporal variability of concentrations, and the scale of change in livestock numbers, the objective is to demonstrate whether a programme of measurements and modelling would be able to measure the change with sufficient precision to improve the emission-concentration relationship. In the event that the changes are shown to be detectable, the project will recommend a strategy for a potential monitoring and modelling programme.

The expected results of this project are highly policy relevant in that they will help to reduce the uncertainties in abatement measures for agricultural trace gases. As the UK is currently under pressure to reduce emissions to the atmosphere from agricultural sources (e.g. UNECE Gothenburg Protocol, EU National Emissions Ceilings Directive, Kyoto Protocol), it is essential to be able to demonstrate with confidence that these links apply in order to justify the economic costs of abatement.
The overall task is to analyze the potential to use the changes following FMD to reduce uncertainties in the link between agricultural trace gas emissions and concentrations in the atmosphere. This includes the following specific objectives:
1. To combine data on animal numbers slaughtered with the Agricultural Census and modified agricultural practices in the light of FMD to estimate revised agricultural emissions for NH3, CH4 and N2O including the spatial assessment across the UK, and in selected case study areas.
2. To utilize the emission data to run the UK scale FRAME model to estimate the effect of FMD on NH3 and other trace gas concentrations, providing maps of the concentration change signal.
3. To consider two case study regions for more detailed analysis including the potential to apply the LADD model at a 1 km level. It is proposed to focus on a) the Eden Valley and surrounding areas in Cumbria and b) west Devon, as these are both areas where there have been large numbers of animals lost due to FMD.
4. To analyze the predicted changes in trace gas concentrations in order to set detection targets for possible monitoring activities and to review the precision of available monitoring methods to establish whether these will be able to detect the changes expected.
5. To review the expected temporal and spatial variability in concentrations to establish the duration and spatial coverage of measurements that would be necessary to assess the changes expected.
6. To report whether a combined measurement-modelling programme would be expected to quantify the changes and if so to recommend an experimental strategy.
Project Documents
• Final Report : Monitoring and modelling trace-gas changes following FMD to reduce the uncertainities in agricultural emissions...   (1362k)
Time-Scale and Cost
From: 2001

To: 2001

Cost: £36,623
Contractor / Funded Organisations
Natural Environment Research Council
Air Pollution              
Environmental Protection              
Sustainable Production              
Fields of Study
Environmental Protection - Agriculture