Changing fertiliser would be ‘a cheap win’ to reduce emissions – Prof. John Fitzgerald

Changing the type of fertiliser used in agriculture would be a ‘cheap win’ in mitigating agricultural emissions, according to the chairperson of the Climate Change Advisory Council.

Prof. John Fitzgerald made the comment on Morning Ireland on RTÉ Radio 1 this morning, Thursday, April 30.

“There are some cheap wins in agriculture, like changing the type of fertiliser used. That will save just under 1% of our national emissions, at very little additional cost,” Prof. Fitzgerald remarked.

So there’s some easy wins, and there’s investment in the future.

That future investment, the Trinity College economics professor stated, would include a change in land use.

“I think it’s important to focus on land use, because if you suck carbon out of the atmosphere, it’s as good as stopping carbon emissions into the atmosphere.

“For example, if farmers planted some of their land with woodland, that would suck carbon out of the atmosphere; it would provide them with a more secure income than they have at present; and as some land would be used for woodland, there would be less for cattle,” the economist asserted.

He claimed that this would be a “win-win” for farmers and the climate.

“It would not half emissions in agriculture, but you could get net emissions from agriculture down significantly,” he added.

New research on agri-emissions

During the interview, the professor also reiterated the oft-repeated statistic that agricultural emissions account for around one-third of Ireland’s total greenhouse gas (GHG) emissions.

However, yesterday this publication highlighted that new research suggests that emissions from livestock manure “patches” are lower than previously thought – which could work to the advantage of Ireland’s pasture-based livestock systems.

A recent project focused on measuring nitrous oxide (N2O) from animal urine and dung patches during spring, summer and autumn on three types of pasture soils: well-drained; moderately-drained; and poorly drained.

Conducted by Teagasc researcher Dominika Krol, the project established that the average emission factors of nitrous oxide were “substantially lower” than the default emission factors of the Intergovernmental Panel on Climate Change (IPCC) – which estimated the “excreta-derived nitrous oxide” figure at 2%.


Earlier this year, Prof. Fitzgerald acknowledged that the way methane is treated and measured in climate change science is “probably not appropriate”.

He was speaking at an event in Dublin titled ‘Climate Change in Agriculture: A balanced Approach’, which was organised by the Irish Farmers’ Association (IFA) last January.

During a panel discussion, Prof. Fitzgerald acknowledged that methane had a different role as a GHG compared to carbon dioxide, and that there were ways of dealing with it aside from simply herd reduction.

“How we treat methane, probably, from a scientific point of view, is not appropriate, and if we use that metric, and we want to be carbon neutral by 2050, then we would have to get rid of all our cows,” he added.

He noted: “For that reason, it would be right to have a change in the way Europe and the world measures [methane].”