Randomized national land management strategies for net-zero emissions

Global scenario modelling for climate stabilization lacks national resolution, particularly for the agriculture, forestry and other land use (AFOLU) sector, impeding effective national climate policymaking. We generate 850 randomized scenarios of activity combinations for Ireland’s AFOLU sector in the year 2050 and evaluate associated greenhouse gas fluxes to the year 2100. Using a GWP100 ‘net-zero’ greenhouse gas definition, 146 scenarios achieve AFOLU climate neutrality and 38 contribute to national neutrality (a substantial AFOLU sink) by 2050. Just one scenario contributes to national climate neutrality to 2100, reflecting future declines in CO2 removals by new forests (excluding potential downstream mitigation). In the absence of technical solutions to dramatically reduce the emissions intensity of bovine production, national milk and beef output will need to be substantially curtailed to achieve net-zero emissions. Active CO2 removal on destocked land, via organic soil rewetting and ambitious afforestation, could moderate output declines in milk and beef production, reducing international carbon leakage risks.