The ‘Global Stocktake’ and the remaining carbon budgets for G20 countries to limit global temperature rise to +1.5 °C

Abstract

AbstractThe G20 brings together the world's major economies. Its members represent 85% of global GDP, 75% of international trade, and two-thirds of the world's population. According to the Intergovernmental Panel on Climate Change, the total remaining global carbon budget required to limit the world's temperature increase to 1.5 °C (with 67% likelihood) is 400 GtCO2, decreasing to 50% likelihood if emissions reach 500 GtCO2 between 2020 and 2050. The UNFCCC's ‘Global Stocktake’ addresses the distribution of the remaining carbon budget to countries and industry sectors, to assess the technical, financial, and policy measures required for decarbonization and the national and international responsibilities involved. In this paper, the decarbonization pathways for all G20 member countries with high technical resolution, are broken down into key industry sectors. The energy-related national carbon budgets necessary to maintain the remaining global carbon budget between 400 GtCO2 and 500 GtCO2 are calculated and a new methodology how a fair distribution can be achieved, considering the historical emissions and economic situations of all G20 countries is presented.