Teagasc has suggested a recent carbon report published in New Zealand contains errors, uses a mix of methodologies, uses old data and fails to reward recent advances in Irish nutrient efficiency.

Teagasc publicly responded to research published in New Zealand which outlines significant differences between New Zealand's and Ireland's carbon footprints.

Last Friday [5 January], DairyNZ and Ag Research published a report suggesting Ireland has a carbon footprint 60% higher than New Zealand.

Calculation of figures

Teagasc took issue with a number of factors used in calculating the figures involved.

The Teagasc response states: “The New Zealand report quotes a carbon footprint of 0.74kg of CO2e per kilogram FPCM [fat and protein corrected milk] for New Zealand [year 2017-2018].

"Including direct land use change [forestry to dairy pasture] brings this figure to 0.88kg of CO2e per kilogram FPCM.

"Ireland’s footprint based on these studies, which include land use change, for a similar time period is 0.99kg of CO2e kilogramme FPCM when account is taken of new nitrogen fertiliser and manure emission factors.

"This difference is much smaller than the headline figures in the report."

Poor research

According to Teagasc, the report fails to satisfactorily address the land use change issue or feed coming in and out of farms.

As an example of the importance of this issue, the Teagasc National Farm Survey 2019 Sustainability report outlines the average carbon footprint of Irish milk to be 0.73kg or 1.14kg CO2e per kilogramme FPCM, depending on the methodology used (national inventory methodology or a full life cycle analysis).

Teagasc states that the New Zealand report made no attempt to compare countries based on representative data.

Teagasc pointed out that the data included in this report for Ireland relates to 2012 and 2014

Teagasc also found a number of calculation errors which have a material effect on carbon footprint calculations within the report.

These calculation errors are additional to incorrect numbers being taken from the Irish papers, as well as deviations from the stated methodologies.

Within the report, the calculated Irish number was 1.18kg of CO2e per kilogramme FPCM.

Teagasc's examination of the paper indicates that correction of the errors included would put the Irish number at 1.06kg of CO2e per kilogramme FPCM.

Finally, Teagasc pointed out that the data included in this report for Ireland relates to 2012 and 2014 (a time when cow numbers were increasing while milk output was restricted).

Recent updates to the Teagasc GHG emissions model based on newly developed country-specific emission factors, and more recent yearly data, show this carbon footprint reducing to 1.01kg of CO2e per kilogramme FPCM.

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