Opportunities to stem methane emissions from livestock could be lost if the way the UK accounts for its greenhouse gas emissions is not addressed urgently, a farmer-funded thinktank has said.
The Commercial Farmers Group (CFG) has called on the UK to urgently adopt a dual accounting approach using two different models side-by-side.
The group said this approach would help cattle and sheep farmers manage methane outputs better and even provide offsetting opportunities for other industries.
The call comes as a new United Nations report on the potential for methane mitigation was recently published.
It said curbing emissions from ruminant livestock presents opportunities, but the potential is hard to measure and estimates fluctuate significantly.
Andrew Loftus, Yorkshire farmer and member of CFG, said the lack of suitable accounting methods only confounded this further.
“It means the UK livestock industry cannot access accurate and consistent feedback on the real warming impact of methane emissions and the success of different mitigation efforts.”
He said the commonly used ‘GWP100’ accounting method was reliable at measuring gases which lasted hundreds or thousands of years, but it did not work for ‘biogenic’ methane from ruminant livestock,.
“This is methane that is belched when the animals digest forage, broken down after only 12 years into water and CO2, then locked back up by pasture and forage crops through photosynthesis.
He said this was a completely different proposition from, for example, CO2 produced from burning fossil fuels: "That’s why we need a different way of measuring methane’s impact."
The alternative model to address this problem already exists. GWP*, developed at University of Oxford, reflects the true warming impact of individual gases, particularly those of short-lived climate pollutants such as methane.
It is this model the CFG wants to see officially recognised by the UK governments for accounting purposes alongside GWP100.
Mr Loftus said New Zealand already led the way in adopting GWP* alongside GWP100, but the concept had not yet gained wider traction.
“Everyone we speak to who understands the scientific principles behind greenhouse gas accounting, whether researcher or politician, has acknowledged the superior ability of GWP* to measure actual climate warming – its validity is not questioned.
"The issue with adoption seems to be inertia and reluctance to move away from the status quo,” Mr Loftus explained.
Professor Myles Allen of Oxford Martin School at University of Oxford, whose team developed GWP*, has stressed the importance of using the correct measures to achieve the required results.
He said that having decided to aim for climate neutrality, there was a simple choice: “We can define climate neutrality in terms of metric-equivalent emissions…or in terms of warming-equivalent emissions.
"This should be an open and public discussion, because the implications, particularly for agriculture, are profound.
“Achieving climate neutrality in terms of metric-equivalent emissions could mean eliminating practices, such as ruminant agriculture, that are not actually causing global warming.
"Warming-equivalent emissions [such as GWP*] resolve this problem,” Professor Allen stated.
He also warned that failure to address fossil fuel emissions continues to be the bigger issue which overrides any discussion on how to measure methane.
“Fossil fuel emissions are driving up global temperatures by two-tenths of a degree a decade. Until we stop doing that, everything else is kind of moot.”
With the UK hosting both the G7 summit in June and COP26 in November, the CFG said the UK had a unique opportunity to lead on meaningful greenhouse gas accounting.
Mr Loftus added: “Accurate measurement would unlock new technologies to mitigate warming and balance high quality, home-grown protein production with the complexities of optimising land use and reinstating biodiversity.
"It would show tremendous leadership if the UK became the first G7 country to implement dual accounting.”
