The emissions gap between the Copenhagen pledges and the 2 °C climate goal: Options for closing and risks that could widen the gap

Abstract As part of the Copenhagen Accord, Annex I Parties (industrialised countries) and non-Annex I Parties (developing countries) have submitted reduction proposals (pledges) and mitigation actions to the UNFCCC secretariat. Our calculations show that if the current reduction offers of Annex I and non-Annex I countries are fully implemented, global greenhouse gas emissions could amount to 48.6–49.7 GtCO2eq by 2020. Recent literature suggests that the emission level should be between 42 and 46 GtCO2eq by 2020 to maintain a “medium” chance (50–66%) of meeting the 2 °C target. The emission gap is therefore 2.6–7.7 GtCO2eq. We have identified a combined set of options, which could result in an additional 2.8 GtCO2eq emission reduction. This would lead to an emission level just within the range needed. The options include reducing deforestation and emissions from bunker fuels, excluding emissions allowance increases from land use and forestry rules, and taking into account the national climate plans of China and India. However, there are also important risks that could widen the emissions gap, like lower reductions from countries with only a conditional pledge and the use of Kyoto and/or trading of new surplus emission allowances.

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