Tom Baxter on: The ruminant in the room

For all the attention devoted to coal phase-outs, electric vehicles, hydrogen projects and carbon capture schemes, one-quarter of global greenhouse gas emissions remain tied to how we farm, says Tom Baxter

The IPCC estimates that land use contributes about one-quarter of global greenhouse gas emissions, notably through methane from rice cultivation and ruminant livestock, and nitrous oxide from fertiliser use.

Yet compared with energy, industry and transport, reducing these emissions receive much less attention. And the reasons are not difficult to understand.

Unlike energy and industrial emissions, which are often concentrated in large facilities, agricultural emissions are dispersed across millions of farms and billions of animals. That makes them inherently harder to measure, monitor and regulate.

Food production also occupies a unique place in society. Farmers are not simply producers of a commodity; they are often seen as custodians of rural communities, landscapes and national heritage.

Beef, dairy and other agricultural products contribute significantly to economic activity, employment and trade balances. Governments are understandably cautious about policies that could undermine competitiveness or simply shift production and emissions elsewhere.

There is also an uncomfortable reality that policymakers rarely discuss openly. Significant reductions in agricultural emissions may ultimately require changes in consumption patterns, particularly in countries with high levels of beef and dairy consumption. Asking people to change what they eat is politically far more challenging than changing how electricity is generated.

Yet the climate significance of agriculture is difficult to ignore. Reducing methane emissions can deliver climate benefits far more rapidly than

"The he climate significance of agriculture is diffifcult to ignore"

carbon dioxide reductions. So agricultural methane deserves serious attention.

Unlike the power sector, agriculture currently lacks an equivalent technological breakthrough. Wind and solar became attractive not only because they reduced emissions but because costs fell dramatically. Agriculture has promising options, including methane-reducing feed additives, improved breeding and precision farming. But none has yet delivered the transformative impact that renewables achieved.

Honest conversations

If climate targets are to be achieved, agriculture must play its part alongside lifestyle, energy, industry and transport. A credible pathway forward requires an honest conversation about people, profit and planet impacts. It requires acknowledging that climate policy cannot focus exclusively on smokestacks, power stations and vehicle exhausts while avoiding difficult conversations about food systems and land use.

This is not an argument for vilifying farmers, nor for imposing simplistic solutions on a complex sector. It is an argument for consistency. If we are serious about reducing greenhouse gas emissions, every major source must be part of the discussion.

Chemical and biochemical engineers have an important role in turning promising ideas into practical, scalable solutions. Biochemical engineering can help unlock the biology; chemical engineering can help make it work safely, efficiently and economically at scale.

Agriculture needs innovation, together with systems thinking and engineering practicality. There will be no single technological fix for the ruminant in the room.