The Emissions Gap report is the latest in a series of analyses looking at the effect of recent climate action on future climate change projections. The INDC pathway examined in the report runs over the next 15 years up to 2030, and it is expected that deeper action will be required over the last 10 years of that period in order to bring the global economy fully onto the cost-optimal pathway by 2030. After 2030, further rounds of national reductions will be required to keep on the cost-optimal pathway to holding warming below 2˚C, a pathway that eventually brings global emissions down to zero somewhere in the 2050 to 2070 period.
The question of how reductions might increase beyond what the INDCs offer both before and after 2030 is critical for evaluating how the current round of commitments contributes to the goal of limiting warming to 2˚C. Without the possibility of additional action before 2030, the current INDCs are insufficient for holding warming below 2˚C without having to endure major economic dislocation after 2030.
As a result, the option to include a mechanism in the Paris agreement to continually review and revise climate action commitments is gaining attention. In a recent bilateral statement, France and China—the world’s largest carbon emitter—both came out strongly in support of engraining a regular five-year review of commitments into the Paris deal, so that countries can assess and enhance their plans. This reiterates the statement made by President Xi Jinping and President Barack Obama in a September bilateral, in which the two nations agreed that the Paris agreement should focus on ramping up ambition over time.
Last week, the UNFCCC released its official analysis of the submitted INDCs, which found that the climate action plans will slow emissions growth by around a third for 2010-2030, compared to the 1990-2010 period. This represents a 4Gt reduction in emissions by 2030 compared to a business-as-usual scenario.
Climate Interactive and Climate Action Tracker also both recently released similar analyses, with findings that differed on the basis of expectations of post-2030 action. Climate Interactive found that current action plans put the world on a course for 3.5˚C of warming by 2030, but its model assumes that no further action takes place after 2030. Climate Action Tracker used a model that assumes continued action after 2030 as the world continues to transition to a renewable energy economy, finding that the INDCs put countries on a path that limits projected warming in 2100 to 2.7˚C.
Overall, the models indicate that the INDCs will result in deeper, steeper, and cheaper emissions reductions if implemented promptly and maintained throughout the century.
This report is coming less than a month before the 21st Conference of Parties (COP21) to the UN Framework Convention on Climate Change (UNFCCC), taking place in Paris from November 30-December 11. At these talks, ministers, negotiators, and heads of state will work to finalize a historic international climate deal.