Agriculture and forestry combined are “a greater sink than source of greenhouse gases (GHGs)”, according to global air pollution expert Dr. Frank Mitloehner.

In an interview with AgriLand about Irish agriculture’s carbon footprint, the professor and air quality specialist in the Department of Animal Science at the University of California (UC) in the city of Davis in the US, highlighted the significant findings that emerged in the latest US National Emissions Inventory, conducted by the Environmental Protection Agency (EPA).

The EPA’s National Emissions Inventory contains measured, modeled and estimated data for emissions of all known source categories in the US.

During a discussion on the growing pressure that Irish farming faces in terms of tackling its 34% carbon footprint against a backdrop of powerful environmental lobbies proposing drastic changes to the sector, Dr. Mitloehner warned against “playing dangerous” with the country’s “most strategically important sector”.

He pointed instead to the “lifestyle choices” of the masses.

This is his response:

Dangerous game

“Fossil fuel related activities in a country like yours make up about two thirds of all emissions and to reduce those everybody has to do something; it would actually hit everybody – meaning every voter.

“It’s easier to just point fingers at a small minority of farmers, than deal with the masses of people who will be inconvenienced if their lifestyle choices were questioned.”

Highlighting research carried out at UC Davis in California – agriculture is a significant sector in California’s economy, producing nearly $50 billion in revenue annually; the state produces two thirds of US fruits and nuts.

Dr. Mitloehner said they compared 40 different land forms with research on their environmental footprint.

“We compared almond orchards, to walnut orchards, to rice fields, to beef ranches, to dairy farms and so on and we compared them to urban encroachment – in other words to urban residential encroachment.

“So we looked at what would happen if you were to replace this agricultural use of land with housing and the outcome was that, on average, the residential housing on an acre of land is 70 times worse for the environment than any of the agricultural land users.

“What I think is happening right now is that there are interested parties in Ireland, and in other parts of the world, that are dangerously playing with the most strategically important sector of society.

“And the most strategically important sector of society is the sector producing food.

“It is the sector that is producing food that is the most important in society; if you cannot feed your people you have a huge strategic problem.”

Grass sink

The professor emphasises this point by drawing attention to Ireland’s green landscape.

“What does the vast majority of Ireland look like? It’s green. And there is a reason why it’s green.

“You have an enormous amount of forage in Ireland. The natural land use for a place like Ireland is of course the use of ruminant livestock because a lot of the land we have is not arable.

“A lot of the land we have cannot be made into crop land because it is marginal, it doesn’t have good enough soils for the most part and, therefore, it is used for grazing.

“And that grazing has a massive impact on or as a carbon sink.”

While Dr. Mitloehner acknowledges that the following is not specifically linked to Ireland, in his expert scientific opinion – the professor has a degree in animal science; a masters in agricultural engineering (specialising in the environmental impact of livestock); a PhD on the environmental management of feedlot cattle – he believes it’s most likely plausible on this side of the pond.

“I’m not sure whether what I say now follows true for Ireland, but I assume that it does.

“The EPA in the US does an annual [National] Emissions Inventory of all sources, of all sectors of society – including agriculture, forestry, transportation and everything else.

“According to the EPA in the US the agriculture and forestry sectors combined are a greater sink than source of GHGs.

“In other words, agriculture and forestry put away more GHGs in the soils and in the plants than they emit.

“The same is true in accordance with the Intergovernmental Panel on Climate Change IPCC [the IPCC is a United Nations body created to provide policymakers with regular scientific assessments on climate change, its implications and potential future risks] and the same is true globally.

“Agriculture and forestry globally sequester and assimilate more carbon than they emit.

“And if people don’t believe me, all they need to do is go to the IPCC recent land use change document and there they will find it.”

The IPCC Climate Change and Land report was published in August 2019.

Scientific assertion

The professor is firmly of the view that agriculture and forestry are the only two sectors in society that have huge potential “as a solution provider” to the world’s climate debacle.

Again he backs up his assertion with science.

“I contrasted the impact of agriculture and forestry on the emissions side and on the sink side using EPA numbers from the US.

“What I found was that agriculture and forestry emit or produce 560 million metric tonnes of GHGs and they reduce 720 million metric tonnes of GHGs in the US today.

“The reason why this is so important is because you have these ‘destructors’ who use this subject to get rid of animal agriculture – which is probably the most strategically important sector in Ireland.

“They [the ‘destructors’] are playing with your food supply chain, politicising it and so far they are doing really well.”

What is sequestration?

The professor says it’s time that Irish scientists look into issues such as the sequestration rates of the country’s soils and pastures.

“Pastures have huge sequestration rates because the plants and the grasses take on CO2.

“The CO2 goes right to the roots and the carbon is taken on by soil microbes – it’s kept there.

“That is called carbon sequestration; it’s kept there.

“The grass is eaten up by livestock, the carbon is still in the root and in the soil and so the amount of carbon that your grassland sequesters might be massive.”

Stay tuned for more from AgriLand‘s interview with Dr. Frank Mitloehner…