With other sectors of the NI economy able to de-carbonise more rapidly, NI agriculture is left with a growing proportion of total NI carbon emissions.

The latest greenhouse gas (GHG) statistics published by DAERA show that, in 2023, agriculture accounted for 30.8% of total emissions, up from 29.1% in the previous year. Agriculture has the largest share, followed by domestic transport at 21.5% and Buildings at 13.8%.

The GHG data are all compared to a baseline year of 1990. Back then, agriculture accounted for 19.6% of emissions, with the list headed by electricity supply at 20%.

It is one of the sectors that has made most progress in cutting emissions, with those emissions down 60% since 1990, mainly because electricity generation has transitioned away from coal-fired power stations.

Since 1990, only two sectors have failed to cut total emissions, with domestic transport up 4.8% and agriculture up 8%.

However, over three-quarters (76%) of agriculture emissions is methane produced by ruminant animals.

It remains a contentious area that the government inventory treats methane in the same way as it treats carbon dioxide (CO2) released when fossil fuel is burned. It is widely accepted that methane from ruminants is part of a natural cycle.

After methane, the next-largest contributor to the agriculture total is nitrous oxide at 19%. It is mainly released when chemical nitrogen fertiliser is spread.

UK totals

Across the UK as a whole, agriculture accounts for a much smaller proportion of the economy than it does in NI. As a result, it makes up just 12.1% of GHG emissions.

Domestic transport is the largest emitter at 29%.

Legislation

With a significant proportion of the UK food supply coming from NI and in recognition of the fact it is difficult to cut agriculture emissions, the UK Climate Change Committee (CCC) advised NI not to opt for a net zero GHG target by 2050.

Instead, the CCC recommended a target to reduce 2050 emissions by 82% when compared to the 1990 baseline. That advice was ignored by a majority of NI politicians and a net zero target was included in the 2022 NI Climate Change Act.

Last December, Stormont passed legislation which sets interim targets for 2030 and 2040.

By 2030, emissions must be 48% lower than 1990 and by 2040 the target reduction is 77%.

The targets look to be incredibly challenging. From 1990 to 2023, NI emissions have fallen 31.5% from a starting point of 26,577 kilotonnes of CO2 equivalent (ktCO2e) to 18,212 ktCO2e in 2023.

To meet the 2030 target it needs to drop to 13,820 ktCO2e.

Based on the rate of change seen over the last 25 years, our projections suggest NI emissions in 2030 will still be over 17,000 ktCO2e.

Achieving the 2030 target will therefore require a massive uptake of new domestic heating systems, electric cars etc.

In agriculture and land use, it will require significant investment in peatland restoration and a major roll-out of methane suppressing feed additives.