Rural Landscape

This project aims to bring some clarity on the extent to which commonly used tools diverge in their estimates of carbon footprint for a range of well-defined reference systems.

Furthermore, it seeks to identify the major sources of divergence and to provide some recommendations on specific areas for further work to tighten up the guidance in accordance with the best available science.


1) To establish a set of reference systems on which to undertake the inter-comparison of tools. The full range of UK farm types will be included, as per Defra’s robust farm type classification (As defined in the Farm Business Survey): Cereals; General Cropping; Horticulture; Specialist Pigs; Specialist Poultry; Dairy; LFA Grazing; Livestock; Lowland Grazing Livestock; Mixed

2) To establish and characterise the current range of foot-printing tools available. There are over 60 tools currently available, and a comprehensive assessment of all of these would be prohibitive.

3a) To summarise and characterise the differences between the outputs and inputs of various tools, for a range of farming systems with a focus on methodologies, treatment and presentation of carbon sequestration and of land use change.

3b) Present variability of results, identifying key drivers that give rise to differences in outputs, and map out the benefits and limitations of methodologies implemented in tools across a range of emissions pathways to include, but not restricted to: Enteric methane emissions; Manure storage and management emissions; Emissions from soil nutrient management; Emissions from crop residues; Emissions from land use change and land management; Upstream emissions from inputs to the system (fertilisers, feeds, agrochemicals).

4) To summarise key recommendations for future work; setting out recommendations on how divergence between tools could be reduced. Where possible to identify existing standardised methodologies to address deficiencies, e.g., internationally accredited methods from relevant institutions (IPCC etc.)

NB: Analysis of the functionality of six carbon calculators was conducted in May 2023 based on the versions publicly available at that time. Most of the calculators then assessed have been updated during and since data collection, including to address some of the research recommendations. Analysis results are anonymised and do not endorse any one calculator.

Access the full report below.

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ADAS provides ideas, specialist knowledge and solutions to secure our food and enhance the environment. We understand food production and the challenges and opportunities faced by organisations operating in the natural environment

In 2015, the UK pledged to be Net Zero by 2050, with the NFU striving for the more ambitious target of 2040. Net Zero is achieved when the amount of greenhouse gases (GHG) emitted is balanced with those removed from the atmosphere. This helps to combat climate change and reduce global warming.

The Department for Environment Food & Rural Affairs.

The number of tools and calculators available can be daunting. None are necessarily right or wrong, the appropriate tool for you depends on the question you are asking.

The UK Government has set a Net Zero target for 2050. Land use and management has a key role to play in this, with the NFU setting an even earlier target of 2040.

Lots of initiatives are measuring and reporting the carbon or greenhouse footprint of products or activities, including crops, livestock and food.

Climate change threatens our ability to ensure global food security, eradicate poverty and achieve sustainable development. In 2016, 31 percent of global emissions originating from human activity came from agrifood systems.

The key GHGs for agriculture that contribute directly to climate change are:  Carbon dioxide (CO2)  Methane (CH4)  Nitrous oxide (N2O)   All these GHGs are often grouped under the umbrella term ‘carbon’.