The urgency to adopt measures that reduce greenhouse gas (GHG) emissions must be accelerated in order to meet Ireland’s 2030 target, according to Gary Lanigan, a research officer at Teagasc. To address this issue, a Marginal Abatement Cost Curve (MACC) has been launched, which identifies cost-effective methods to cut GHG emissions and enhance carbon sequestration. In a “business-as-usual” scenario, agricultural GHG emissions could decrease to 17.0 million tonnes of carbon dioxide equivalent (MT CO2eq) compared to 21.9MT CO2eq without any abatement. However, more ambitious adoption rates of mitigation measures are needed to achieve this reduction.
Ireland has committed to a 51% economy-wide GHG emissions reduction target by 2030, based on 2018 levels. Within this, the agriculture sector must reduce its emissions by 25% by 2030. In the base case with high adoption rates, Lanigan believes that the 25% reduction target can be met. The MACC has identified several measures to achieve this, including reducing the finishing age of cattle, replacing fertilizers with protected urea, using feed additives to reduce methane emissions in dairy cows, and diversifying options to displace livestock units.
Lanigan stressed the importance of focusing on cutting nitrogen usage during the current carbon budget (2021-2025) and then tackling methane emissions in the second carbon budget (2026-2030). He emphasized the need to ramp up adoption soon, particularly in the short term. Lanigan acknowledged the progress made in adopting Low Emissions Slurry Spreading (LESS) and protected urea, but highlighted the role of advisors in translating the MACC into sustainable production systems. Teagasc emphasized the need for increased advisory and extension services to guide farmers and landowners towards reduced GHG emissions and climate neutrality by 2030.
Teagasc also highlighted the importance of focusing on nitrous oxide (N2O) mitigation, particularly through managing and reducing the use of nitrogen fertilizers. This can be achieved through reduced application of N fertilizers, altered fertilizers formulations, and the use of clover, legumes, and multi-species swards. In terms of methane mitigation, the MACC suggests reducing the age at finishing, focusing on the dairy Economic Breeding Index (EBI), and using feed additives to inhibit methane production. Additional measures such as slurry additives, biomethane production, extended grazing, organic farming, tillage, and forestry can contribute to meeting targets.
Teagasc acknowledges that the potential for GHG abatement and associated costs/benefits will evolve over time as new mitigation measures are developed and socio-economic conditions change.