Warming impact of methane can be mitigated while farming cattle and sheep
Oxford University research into the global warming impact of methane is critically important because of the impact it could have on future food production and agricultural land use policy.
Key policy points
1. We do not need to give up meat and dairy to stabilise global temperatures. Contrary to recent media coverage, methane emissions from ruminant agriculture have a neutral impact on global warming, so long as emission levels remain stable.
2. Methane is a short-lived gas. If ruminant numbers stay the same, new methane emissions will replace old emissions over a ten year cycle (approx.) and there will be no impact on global warming.
3. The warming impact of other greenhouse gases produced through sustainable grass-based ruminant agriculture can be fully mitigated through on-farm carbon sequestration.
4. Grass-based ruminant agriculture can help deliver other environmental benefits such as improved biodiversity and soil health, and contribute to improved water management.
5. This means that we can strongly support the UK's rural economy – but a transition to grass-based ruminant production is essential.
Farmwel believes that we have a unique opportunity to deliver sustainable agricultural land use. We are strongly urging ministers to deliver fundamental change so that future food production is firmly centred on environmental and welfare quality. Both policy and practice must focus on the restoration and maintenance of soil health, biodiversity, and the quality of water and air.
There is much agreement around the key principles of an Agriculture For All-based approach (for example payments for public goods such as flood prevention). However, there is a danger that inaccuracies around the global warming potential of methane could drive policies which undermine the resilience of the rural economy and stifle action on climate change.
It is important to be very clear - we can rapidly reduce greenhouse gas emissions from agriculture while continuing to support farm businesses rearing cattle and sheep in grass-based systems.
In June 2018 new research was published by International Panel on Climate Change (IPCC) scientists from Oxford Martin School, Oxford University. The research improves upon the methodology currently defining the global warming potential of different greenhouse gases.
Methane is a short-lived gas and should be considered differently from carbon dioxide, a long-lived gas. In fact - in terms of British pasture-fed livestock - it was the great-grandparents of farmers who pushed up atmospheric methane levels when they were first building up their herd of cattle or their flock of sheep. So long as cattle and sheep numbers remain steady, or dwindle, warming from methane remains constant.
The researchers said, "Current climate change policy suggests a 'one-size-fits-all' approach to dealing with emissions, but there are two distinct types of emissions. We must treat these two groups differently." (Professor Dave Frame)
"Long-lived pollutants, like carbon dioxide, persist in the atmosphere, building up over centuries. The CO2 created by burning coal in the 18th Century is still affecting the climate today." On the other hand, "Short-lived pollutants, like methane, disappear within a few years. Their effect on the climate is important, but very different from that of CO2." (Dr Michelle Cain)
"We don't actually need to give up eating meat to stabilise global temperatures. We just need to stop increasing our collective meat consumption. But we do need to give up dumping CO2 into the atmosphere. Every tonne of CO2 emitted is equivalent to a permanent increase in the methane emission rate. Climate policies could be designed to reflect this." (Professor Myles Allen)
Nitrous oxide and carbon dioxide
Global warming presents an extremely serious threat to food production. We believe that it is critical for agriculture to play a fundamental role in reducing society's overall greenhouse gas emissions. But the Oxford Martin research will enable policy-makers to focus their efforts on long-lived greenhouse gas emissions from UK agriculture, particularly from carbon dioxide (from farm vehicles, buildings, equipment, imported feed) and nitrous oxide (primarily from artificial fertilisers).
Mitigating the impact of nitrous oxide and carbon dioxide is achievable. Farmwel has proposed that a farmland forest using up to 10% of farmland should be established to strengthen biodiversity, improve hedgerows, manage water, enrich farm animal environments, improve animal health outcomes, enhance beauty - and sequester carbon.
We have proposed that agriculture should be carbon negative by 2030. All farms should be generating clean energy by 2030, for own use and for export to the grid. Government should support a full range of clean energy options. Each proposal should be considered on a case-by-case basis but a planning presumption in favour of renewables development should be established. Community-based schemes should be welcomed.
The right kind of cattle and sheep farming
Finally, we would like to reiterate that while this research demonstrates that pasture-fed livestock has a negligible effect on global warming, it is extremely difficult to achieve good environmental outcomes while continuing to keep farm animals in the most intensive farm systems, which rely heavily on high protein feeds produced in arable monocultures, on high levels of fossil fuel and water use, and on routine medications often including human-critical antibiotics.
Please find links to the research below, and to an excellent article by Dr Michelle Cain explaining the science. If you have any questions, please contact ffinlo Costain, director, Farmwel
1. Full research: A solution to the misrepresentations of CO2-equivalent emissions of short-lived climate pollutants under ambitious mitigation
2. Research summary
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