Growing Accuracy on Farm Emissions

New ways to measure the amount of greenhouse gases produced by farming will help progress on reduction targets.

Methane and nitrous oxide are unavoidable by-products of farming. But how much of these potent greenhouse gases do UK farms actually emit? A new Department for Environment, Food and Rural Affairs initiative, The Agricultural Greenhouse Gas Research Platform, accredited by Living With Environmental Change, aims to answer this key question with improved accuracy.

This will enable policy-makers and the agricultural industry to track overall progress in cutting emissions. It will also help to assess how effective policy and new farming techniques are in securing reductions.

To date, UK agricultural emissions have been calculated very simplistically. Methane emissions from cows and other livestock are estimated by multiplying the total number of animals by a single value for methane production for each type of animal. For nitrous oxide, emissions are estimated from the quantities of nitrogen-based fertiliser plus manure and urine that are deposited on UK farmland.

The new initiative is employing a more sophisticated approach, to help reflect the reality and diversity of farming inthe UK. Harnessing data from a representative cross-section of farms, the new emissions estimation methodology will factor-in variations in soil types, feed types, mix of breeds and the timings, rates and methods of fertiliser application, for example, as well as climatic conditions. Computer models will help scale up these data and researchers will devise a way to calculate uncertainty in emissions estimates.

Knowledge exchange will play a crucial role. Newsletters, workshops and consultation with groups like the Agriculture and Horticulture Development Board and the National Farmers’ Union, will raise awareness and involvement.

The initiative’s findings should then contribute to roadmaps to help different sectors within agriculture make substantial cuts in greenhouse gas emissions. They will also provide more reliable methods of assessing progress towards greenhouse gas reduction targets set by the agricultural industry and devolved administration governments.