The G-2, The Paris Climate Deal, and the Need for Additional Cycles of Action

Given last November’s historic joint climate announcement, much anticipation has been focused on the contributions of the United States and China towards December’s Paris climate deal. At the end of March, the United States announced its intended nationally-determined contribution (INDC), and China is expected to release the details of its pledge in the next few months. Already, there is concern that the country submissions are behind and that they will not be sufficient to narrow the emissions gap sufficiently after 2020 to contain global temperature rise. That countries might submit less ambitious commitments is a serious concern, as the Climate Action Tracker has said about Japan’s prospective commitments, for example. Either way, the reductions needed to avoid dangerous climate change are so substantial that additional “cycles of action” are needed both at the upcoming Paris Summit and beyond.

While the United States and China’s pledges were deemed substantial for the respective capacities of each country, the fear that other countries would not pledge even more ambitiously has been a concern. As UNEP has highlighted with respect to countries’ 2020 commitments, the post-2020 pledges so far leave a big gap between necessary emissions reductions1 and the sum of countries’ targets. Simply put, going forward, all countries, including the US and China, will need to be more ambitious than the understanding reached by the two countries in 2014. As discussed below, countries will need to do more depending on their level of economic development and other factors. A misunderstanding of this situation could lessen the ambition of INDCs coming from other countries. So far, only a handful of countries have put forth INDCs, including the European Union and the United States. Given limited information and the small number of INDCs put forward so far, we ask, What would happen should the rest of the world – excluding those countries who already announced their commitments – follow the US and China’s lead?

What did the US and China pledge?

In its INDC, the United States committed to an absolute reduction: 26 to 28 percent less greenhouse gas emissions in 2025 compared to 2005 levels. If achieved, the United States would be doubling the pace of reduction it aimed to achieve from 2005 to 2020. China indicated last November its intention to peak carbon emissions “around” 2030, which is significant because of China’s previous strict adherence to emissions intensity-based targets (i.e., reducing its rate of carbon intensive growth, while allowing for overall emissions to continue to grow) and previous refusal to officially commit to a “peak” point after which emissions would level and presumably fall. To add to its pledge, China also announced a target to increase its share of non-fossil energy to around 20 percent by 2030, meaning one-fifth of its projected 4,542 million tons of coal equivalent, or roughly the total primary energy consumption of Central and South America in 2009, would come from non-fossil sources.

These commitments, while significant, will not lead to the global reduction in CO2 emissions needed on their own. Studies show that global emissions cannot exceed 42 GtCO2e annual emissions by 2030 for the world to have a likely chance of staying below 2 degrees Celsius, which scientists say is necessary to avoid the most dangerous impacts of climate change. The last negotiations in Lima decided that all countries should contribute to climate change efforts, but the early leadership of the US and China may mean other countries will be more reluctant to pledge beyond what these two countries have already put forth on the table. Of course, Mexico came forth in late March with a plan to cap its emissions by 2026, but other countries may be reluctant to pledge as ambitiously and default to a “G-2” pledge scenario, depending on their level of economic development.

Where do we stand if countries replicate the US-China agreement with their own INDCs?

We used the C-ROADS tool to model what the gap might look like if countries were to truly follow the G-2 lead on structuring their INDCs (Figure 1). Assuming all developing countries that have not already submitted INDCs peak emissions by 2030, following China’s lead, and all developed countries that have not submitted INDCs follow the US’ reductions,2 there is a significant difference in outcomes by 2030 compared to other early analysis with different scenarios.3

We find that, if these above commitments were applied globally, emissions in 2030 would reach 67 GtCO2e, far more than allowed for by the above 2-degrees scenario. Of course, if countries’ contributions were less than those of the U.S. and China, the shortfall would be even greater.

Still, a central goal of the Paris Conference is to lay a foundation for a truly global effort in which both developed and developing countries make serious commitments and increase their ambition over time. If countries’ emissions reduction pledges were to follow the new G-2 scenario, it would represent a first step—a 10 GtCO2e reduction from business as usual emissions (77 GtCO2e as predicted in C-ROADS from the IPCC AR5 (2013) scenario analysis). This projection is better than what some countries have indicated while drafting their INDCs, but short of what is needed to maintain a least-cost trajectory to stay on-target for the under 2-degree C goal.

Figure 1. A significant gap of 25 GtCO2e between annual global total GHG emissions projected and what is needed to contain global temperature rise within 2 degrees C will result in 2030 if countries adopt a G-2 scenario for Paris contributions.4

What does this all mean for Paris and the US?

As anticipated, many countries missed the March deadline to submit their intended contributions to Paris. Now June’s Bonn intersessional negotiations may be the first indication of how all the pledges add up and what emissions gap remains. As our analysis shows, following the G-2’s lead in specifying mitigation contributions will leave a sizeable gap. However, the gap can be diminished if countries such as South Korea, Singapore, and Mexico—which recently committed to peak its emissions by 2026—pledge cuts that exceed what is “expected” in our scenario above.

Importantly, what is needed is for countries to contribute to deeper cuts as their capacity and respective share of global emissions grow. India’s total annual emissions, for example, are quite high but it emits far below that of developed countries on a per capita basis so is expected to mitigate less now but ramp up action in the future.

Equally critical is the recognition that Paris is just the beginning. Multiple cycles of action – revisiting pledges and reevaluating scenarios consistently – are needed to ensure we are not off-course from global climate goals. The Paris negotiations are vital in forming the bedrock for future discussions to come. As outlined in a recent report by the World Resources Institute and the Agreement on Climate Transformation 2015, the success of the Paris agreement hinges upon provisions that allow for clear and predictable assessment cycles, more ambitious revisions, upward revisions of pledges, and regular assessments of national commitments and the global gap, and that take into consideration an equity framework.

These are lofty goals and all nations, including the US, should measure success by how well they are met. U.S. Secretary of State John Kerry said that the Paris agreement “will not completely and totally be able to eliminate the threat” of climate change, but that “it is an absolutely vital first step” in bringing together countries around the world “to contribute to a solution.” While a G-2 scenario of climate commitments won’t get us to our goals, what is more important is that it lays a critical baseline by which to assess needed action in the near and long-term.


1. The reductions necessary are those required to keep global average temperatures below an increase of 2 degrees Celsius above pre-industrial levels, which scientists say is necessary to avoid the most dangerous impacts of climate change.
2. While, at the time of writing, Switzerland, Norway, the EU, Mexico, Russia and Gabon had all submitted INDCs, the C-ROADS tool only allowed for our team to input the specific commitments of the EU, Mexico and Russia. Switzerland, Norway and Gabon’s emissions, while significant, should not greatly distort the findings.
3. See Climate Advisers, “Gap Analysis with Paris Pledges”; and Climate Action Tracker, “CAT Emissions Gaps”
4. For this analysis we used the SRES A1Fl MINICAM scenario, which emphasizes reliance on fossil fuels resulting in relatively higher projected emissions.


Author Information:
Angel Hsu is a ChinaFAQs Expert at Yale University and an assistant professor of environmental studies at Yale-NUS College. At Yale, she is director of Yale’s Environmental Performance Measurement program.
Andrew Moffat is a Master of Environmental Management candidate at the Yale School of Forestry and Environmental Studies.

Photo credit:
Marionzetta via Flickr, Creative Commons License