DEAR EDITOR

I happened to hear RTÉ’s “Hot Mess” on Wednesday 16 April.

Philip Boucher-Hayes vehemently declared that farmers are “incorrectly” expressing the view that the warming impact of methane from ruminants is not accurately calculated. He then brought on Professor Peter Thorne to back him up. In my opinion, both men were inaccurate and incorrect in what they said, and while it is unacceptable for either of them to be so, it is quite shocking for Prof Thorne as he is a member of the Climate Change Advisory Council.

He must be aware that it is accepted scientifically that the warming effect of methane from ruminants is incorrectly calculated, and a question remaining is, by how much? Prof Thorne also attended an Oireachtas hearing in July 2022 at which this matter was explained by Prof Myles Allen of Oxford University, and at that time he agreed with Prof Allen.

The contention on the radio programe was that biogenic methane – or more specifically, the warming effect of methane from ruminants – was exactly the same as the warming effect of methane from fossil fuels, mining, etc. Prof Thorne said that it doesn’t matter where it comes from, it all has the same effect. In my opinion, this is a very unscientific and juvenile approach.

If we take this logic as being correct, then all carbon dioxide (CO2) has the same warming effect, and it doesn’t matter where it comes from, it all has the same effect: CO2 is CO2, is CO2. This means that biogenic CO2 has the same warming effect as CO2 from burning fossil fuels, meaning that the 3bn tonnes from humans, the 5bn tonnes from cows, the 12bn tonnes from other living creatures should all be recorded as greenhouse gases. However, the fact is, because it is biogenic its warming impact is zero and is calculated as such by the Intergovernmental Panel on Climate Change. It is exactly the same molecule, with exactly opposite effects.

The fact is, that increased temperatures are precipitated by “additional” CO2 in the atmosphere. It is worth noting that ruminants have been around for 40m years and in that time have emitted billions of tonnes of methane, all of which converted back to CO2 after 12 years. The fact remains that after all those billions of tonnes of CO2, there isn’t one “additional” tonne of CO2 in the atmosphere because it is biogenic, or cyclical.

On the other hand, there is a vast amount of “additional” CO2 in the atmosphere as a consequence of the release of fossil methane, because it is not biogenic, not cyclical. It’s all one-way, from being locked safely away in the ground, to being up in the atmosphere.

We need mature debate not any further alienation of the embattled farming community.