Measuring flaws must not stop carbon reduction in farming

Despite flaws in current carbon auditing, the farming industry can’t wait until the perfect system has been developed to start reducing carbon emissions, said former NFU Scotland president Nigel Miller.

While the sector had reduced its emissions of greenhouse gases (GHG) by around 15 per cent since the mid-1990s, farmers were this week told that more needed to be done over a far shorter timescale for the industry to meet the target of a 30 per cent reduction over the coming years to stave off run-away global warming.

Former NFU Scotland president and co-chair of ‘Farming for 1.5°’, Nigel Miller, agreed with concerns voiced during an on-line meeting organised by the union that he many different tools for carrying our carbon audits give different results, but they often failed to tell the full story, focusing on the ‘dirty side’ of emissions while failing to give credit for carbon sequestration.

He said it was likely to be a big challenge – but the industry needed to start building on what was already there and drawing a base-line and adapting as both calculators and the underlying science progressed.

“One of the problems is the decision taken by the Intergovernmental Panel on Climate Change (IPCC) to use to the so-called GWP 100 methodology for enteric methane emissions by cattle and other ruminants which fails to recognise that while methane has a higher warming potential than carbon dioxide, it also has a far shorter half life and would be better looked upon as a cycle.”

Miller said that more recent research at Oxford University recommended that using the GWP methodology which allowed for the shorter half life gave a truer picture of the real contribution made by cattle and sheep.

“But while it’s likely to take a long time to convince the IPCC to change this, doing so will be critical to the future of cattle and other ruminant production.”

He also said that carbon calculators such as the widely used Agrecalc system developed by the SRUC were adapting as time went on to build in the industry’s important role in sequestering carbon, with the latest version set to include the benefits of hedges, which had previously been ignored.

Outlining some of the roads down which policy was likely to develop, Miller said that while there were many win/win situations which would improve efficiencies and reduce economic costs and GHG emissions, he doubted they would be enough to yield the full scale of reductions necessary.

“And it’s worth being aware that while some efficiency measures might reduce the emissions per kg of beef or cereals, if yields increase overall, the total level of emissions won’t fall - so sadly things aren’t as tidy or as pleasant as they could be.”

Carbon contracts could be offered to farmers to help overcome some of the economic hurdles associated with the later stages of emissions reductions.

But Miller also cautioned that contentious land use change – such as de-intensification and forestry -could kick in if other means failed to reduce emissions.