Professor Myles Allen:

Yes. I would characterise it that it would have the same impact on global temperature as taking CO2 out of the atmosphere. If you reduce a herd it has the same impact on global temperature as planting a lot of trees, actively taking CO2 out of the atmosphere. That is why I say that I do not understand why there needs to be a fight over this because actually, that is a good thing. It is simply not acknowledged in the way that we characterise methane's impact at the moment. If it were acknowledged it might go quite a long way to diffuse farmers' concerns. I can understand that farmers are concerned if they are being asked to reduce global temperatures without that service being acknowledged, whereas if you calculated the impact of interventions on global temperatures, it would be acknowledged. That does not dictate policy, I should stress, it just acknowledges the outcome of policy.