Ireland's State of the Environment Report 2024

96 Chapter 4: Climate Change In 2023, greenhouse gas emissions from agriculture decreased by 4.6% (or 1.01 Mt CO 2 eq) following a decrease in 2022 of 0.7% (EPA, 2024b). The most significant factor driving the lower emissions in 2023 was decreased synthetic fertiliser use (-18%) and decreased liming (-27%). The size of the dairy herd continued to increase, for the 13th consecutive year (+0.6% in 2023), with a 4.1% decrease in total national milk production. However, there was an overall decrease in livestock nationally, with non-dairy cattle down by 1.1%, sheep down by 1.2% and pigs down by 4.3%. In terms of future emissions, agriculture emissions are projected to decrease by 1% and 18% over the period 2022-2030 under the With Existing Measures and With Additional Measures scenarios, respectively. The most ambitious scenario, the With Additional Measures scenario, assumes the implementation of Ireland’s 2024 Climate Action Plan with the exception of diversification measures, which do not yet have a sufficiently elaborated implementation pathway to be included in the modelling. The sectoral emissions ceilings for the agriculture sector are 106 Mt CO 2 eq for 2021-2025 and 96 Mt CO 2 eq for 2026-2030. If these ceilings are not exceeded, this would likely approximate a 25% reduction in the sector’s greenhouse gas emissions in 2030 compared with 2018. The most recent Teagasc marginal abatement cost curve 7 publication sets out measures that are to be implemented in the agriculture sector, including the following: ■ Methane emissions are expected to be reduced through a variety of measures, including expanding tillage, increasing organic farming and reducing the methane output from each animal (e.g. through selective breeding, feed additives and earlier slaughter ages). Measures such as an expansion of anaerobic digestion aim to capture more of the methane at source and use it to generate heat and power. ■ Nitrous oxide emission reduction measures include those aimed at reducing the requirement for nitrogen fertilisers and ultimately reducing chemical nitrogen fertiliser usage to 300,000 tonnes by 2030. Some other related measures include the use of low-emission slurry spreading and the planting of clover and multi-species swards. 7 www.teagasc.ie/publications/2023/marginal-abatement-cost-curve-2023---executive-summary.php (accessed 13 September 2024). Transport emissions. Between 1990 and 2023, of all sectors transport shows the greatest overall increase of greenhouse gas emissions at 129.2%, with road transport increasing by 133.6%. Fuel combustion emissions from transport accounted for 9.2% and 24.4% of total national greenhouse gas emissions in 1990 and 2023, respectively. The increase in emissions up to 2007 can be attributed to general economic prosperity and an increasing population, with a high reliance on private car travel and rapidly increasing road freight transport. Over the period, passenger car numbers increased by 191% and commercial vehicle numbers increased by 177%. The increase in transport emissions up to 2007 and the subsequent fall during the financial crisis highlight that transport emissions have not yet been effectively decoupled from economic activity through sustainable planning or electrification. Transport emissions in 2023 marginally increased by 0.3% (or 0.03 Mt CO 2 eq) compared with 2022 emissions. Emissions from road transport were relatively stable for the period 2015-2019, at an average of 12.2 Mt CO 2 eq, but reduced to 10.4 Mt CO 2 eq in 2020, driven by movement restrictions related to COVID-19. However, with the easing and ending of travel restrictions in 2021 and 2022, road transport emissions rebounded to 11.1 Mt CO 2 eq and 11.8 Mt CO 2 eq, respectively, with 2023 emissions still 4.3% below pre-COVID-19 levels. Transport emissions are projected to decrease by 26% over the period 2022-2030 under the With Existing Measures and With Additional Measures scenarios, respectively. The more ambitious With Additional Measures scenario assumes that 943,600 electric vehicles will be on the road by 2030, biofuel blends of 10% for petrol and 20% for diesel will be achieved, and a 20% reduction in total vehicle kilometres by 2030 will have been brought about by Avoid-Shift measures. The sectoral emissions ceilings for the transport sector are 54 Mt CO 2 eq for 2021-2025 and 37 Mt CO 2 eq for 2026-2030, which, if achieved, will approximate to a 50% reduction in the sector’s greenhouse gas emissions in 2030 compared with 2018. The measures planned in the transport sector are predicated on the Avoid-Shift-Improve hierarchy, where Avoid measures aim to result in a lower transport demand, Shift measures seek to move to less carbon- intensive transport modes and Improve measures change technologies to result in lower emissions. In the 2024 Climate Action Plan: