PNNL

Abstract

Climate mitigation targets require a rapid decarbonisation of the global energy system. In this paper, we investigate the extent to which future energy transformation pathways depend on assumptions about economic growth and fossil fuel availability. The analysis synthesizes results from the RoSE multi-model study aiming to identify robust and sensitive features of mitigation pathways under these inherently uncertain drivers of energy and emissions developments. Based on an integrated assessment model comparison exercise, we show that economic growth and fossil resource assumptions substantially affect baseline developments, but in no case lead to a significant decrease of the greenhouse gas emissions reductions that would be needed to achieve long-term climate targets without dedicated climate policy. The influence of economic growth and fossil resource assumptions on climate mitigation pathways is significantly smaller than on baseline trajectories due to overriding requirements imposed by long-term climate targets. While baseline assumptions can have substantial effects on mitigation costs and carbon prices, we find that the impacts of model differences and the stringency of the climate target are larger. We conclude that the inherent uncertainty about socio-economic determinants like economic growth and fossil resource availability is important, but does not preclude a meaningful assessment of the implications of climate policy objectives on mitigation pathways . The RoSE study conducted a number of regional and sectorial analyses of the RoSE energy transformation scenarios that are part of this special issue and briefly surveyed in this overview.