- Joint Program Report
Abstract: To meet the long-term goals of the Paris Agreement, the global energy system needs to transition to a radically different fuel mix than currently in use. We analyze temperature implications of three scenarios of energy transformation developed by Shell International. The Islands and Waves scenarios explore the world development without any specific focus on a pre-determined temperature target. The Islands scenario envisions the world focused on nationalism and own security in a context of steady technological development, while the Waves scenario examines the world that focuses on development first and foremost and only changes late to address climate. The Sky 1.5 scenario explores the challenge of moving to a global economy with net-zero greenhouse gas (GHG) emissions in the second half of the century (specifically by the year of 2067). Using the MIT Integrated Global System Modeling (IGSM) framework, we simulate 400-member ensembles, reflecting uncertainty in the Earth system response, of global temperature change associated with each scenario by 2100 (mean of 2096-2100) relative to pre-industrial (mean of 1850-1900) levels. We find that for the median climate parameters, the global surface temperature increase is 2.52°C for the Islands scenario, 2.28°C for the Waves scenario, and 1.47°C for the Sky 1.5 scenario. The likely (33%-66%) range in 2100 is 2.40-2.64°C for the Islands scenario, 2.19-2.43°C for the Waves scenario, and 1.40-1.59°C for the Sky 1.5 scenario.