Debunking the myths about farming and methane
The National Farmers Union (NFU) have set the ambitious goal of reaching net zero carbon emissions by 2040, a full ten years before the government’s countrywide target of 2050. This is a laudable target which presents some interesting challenges specific to the agricultural sector.
While many sectors emit CO2 and must look for ways to minimise this, the majority of agriculture’s emissions come from methane and nitrous oxide. Balancing this, they have a large capacity to sequester CO2 in soils and biomass. This could be a very big opportunity for farmers as, until carbon capture is demonstrated at scale, they are currently sitting on the only commercially proven method of removing carbon from the atmosphere.
What to do about the sector’s methane emissions, however, is causing some debate. A large proportion of these emissions come from ruminant livestock such as cattle and sheep, discussed recently in documentaries like ‘Apocalypse cow’ and ‘Meat: a threat to our planet’. In response to calls to reduce livestock numbers some farmers have pointed to the short lifetime of methane as a way of suggesting that this isn’t really a problem. However, this narrative is based on a number of myths:
Myth 1. Methane does not accumulate in the atmosphere
A number of farming groups have suggested that the shorter lifetime of methane, compared to CO2, means that it does not accumulate in the atmosphere. This would only be true if emissions were less than or equal to removals. This is not the case. Atmospheric methane concentrations are increasing rapidly and there is evidence to suggest this is due to both increased emissions and a decreased capacity for removal.
Myth 2. The short lifetime of methane means impacts are insignificant
The Paris agreement aims to limit global temperature rises to 1.5 degrees by 2050 meaning we do not have much time to act. Although the average lifetime of methane in the atmosphere is around 12 years, this is only an average so, coupled with thermal inertia (the lag in response of the climate system to greenhouse gas emissions), heating effects will be felt for decades even if we stopped emitting it tomorrow. This is made even more important by the fact that, as our understanding of atmospheric processes increases, the global warming potential of methane has been revised up. Future IPCC reports will use a value of methane having either 28 or 32 times the impact of CO2, up from 25.
Myth 3. Only additional emissions count
One argument suggests that if a herd has been around for generations then it has no climate impact because it’s not creating any additional emissions. Therefore it isn’t responsible for climate change. This is clearly false. All emissions count, no matter how long they have been going on. Claiming that yours isn’t the straw which broke the camel’s back isn’t going to help if every sector of the economy says the same thing.
While some beef producers have been relying on these myths to claim they are not contributing to climate change, the NFU has not made the same mistake. Their report focuses on improving diet and cattle health to lower methane emissions. This can result in significant reductions in methane production and further research in this area should be supported so that livestock farmers have the information they need to adopt good, low carbon practices (some of which we have covered in our report on reducing consumption emissions in cities).
Ultimately, farmers need incentives to lower their emissions and sequester more carbon. Improved diet and cattle health can play a big part, but we can’t ignore the fact that the majority of reductions in agricultural emissions since 1990 can be attributed to falling numbers of cattle and sheep.
Farmers should be rewarded for low carbon, nature friendly farming
Transitioning to smaller herds or switching out of beef and dairy is unlikely to happen without a payment system which rewards low carbon, nature friendly farming and proper monitoring of farming emissions.
The forthcoming Agriculture Bill should encourage farmers to produce public goods including carbon sequestration and increasing biodiversity. How farmers meet the challenge of net zero will ultimately depend on a range of factors from climate, to soil type and local traditions, however we need to be open to the possibility that reducing cattle and sheep production could be one of the tools in the box. Lower meat consumption is not a silver bullet which will solve emissions from the agricultural sector but, in a climate emergency, it should be encouraged alongside a just transition for farmers.