PNNL

Abstract

Several studies have shown that the greenhouse gas reduction resulting from the current Intended Nationally Determined Contributions (INDCs) will not be enough to meet the overall targets of the Paris Climate Agreement. It has been suggested that intensifying the reduction of short-lived climate forcer (SLCF) emissions could potentially be a way to reduce the risk of overshooting the 1.5 or 2oC target in a cost-effective way. In this study, we employ eight state-of-the-art Integrated Assessment models (IAMs) to examine the global temperature effects of ambitious reductions in 1) methane, 2) black and organic carbon, and 3) hydrofluorocarbon emissions. The proposed SLCFs measures are found to have a relatively large effect on reducing the short-term global mean temperature (GMT) (In the year 2040: -0.03oC to -0.15oC) and on reducing the short-term rate-of-change (by up to 15%), but only a small effect on reducing the maximum temperature change before 2100, because later in the century these gases are already significantly reduced, either directly or indirectly due to changes in the energy system. All three SLCF groups can contribute to achieving GMT changes.