Aidan Harrison’s letter (23 June) took issue with George Monbiot’s argument that grazing cattle and sheep impose a huge environmental cost (Opinion, 20 June). However, Harrison’s criticisms were deeply flawed.
Ruminant animals such as cattle and sheep produce methane, an immensely powerful greenhouse gas. Harrison argues that these emissions do not matter because they are relatively short-lived and in some sense “natural”. But a flow of continued methane emissions from any source warms the planet, and that warming effect will only decline if the emissions are reduced. Indeed, precisely because methane is short-lived in the atmosphere, cutting methane emissions is the fastest-acting lever we can pull to moderate temperature rise and reduce the risks of self-reinforcing climate change.
That point is made clearly in a rigorously scientific and carefully balanced 2020 report by the Food Climate Research Network, Grazed and Confused?, which also analyses in detail oft-repeated claims that grazing cattle or sheep can deliver such a large increase of carbon sequestration in the soil as to offset the effects of methane (and also nitrous oxide) emissions. Its conclusion is that any such offset amounts only to between 20% and 60% of the adverse effects. And as Monbiot argued, the sequestration achieved would be considerably larger if grazing land were converted to woodland.
We do not need to reduce beef or lamb production to zero in order to solve the challenge of the climate crisis, since small residual emissions in many sectors of the economy can be offset by some limited use of carbon removal techniques. But the simple fact remains that one of the biggest things that ordinary citizens can do to reduce their own climate impact is to significantly reduce red meat consumption.
Former chair, Climate Change Committee, 2008-12