Despite 23 years of negotiations since the 1992 Rio Earth Summit, global greenhouse gas emissions continue to rise.
But last week, in an impressive display of international unity, delegates from 195 countries agreed to a climate deal to keep global warming to “well below” 2 degrees Celsius above pre-industrial levels by 2100. The Paris Agreement recognizes that warming above 2°C would all but guarantee devastating sea-level rise, floods, droughts, food insecurity, and ecological disruption. The agreement also cites 1.5°C as an aspirational warming limit, recognizing that warming above 1.5°C could jeopardize low-lying island nations.
Climate delegates and world leaders heralded the agreement as a milestone. India’s environment minister called it “a new chapter of hope in the lives of 7 billion people.” China’s climate envoy called the agreement “fair and just, comprehensive and balanced, highly ambitious, enduring, and effective.” And, according to President Obama, “the Paris Agreement establishes the enduring framework the world needs to solve the climate crisis.”
But the Paris Agreement will not singlehandedly prevent catastrophic climate change. The fully implemented agreement likely would result in warming of around 2.7°C by 2100, according to Climate Action Tracker. Why does the agreement fail to keep warming below 2°C?
In short, the Paris Agreement fails to keep warming below 2°C because the country-by-country emissions reduction goals that form the backbone of the agreement’s international mitigation strategy are not ambitious enough.
In the years leading up to Paris, the Conference of the Parties of the United Nations Framework Convention on Climate Change (UNFCCC) invited all parties to submit national plans detailing how and how much they plan to reduce domestic greenhouse gas emissions post-2020. These plans are called “intended nationally determined contributions,” or INDCs. They form the heart of the Paris Agreement’s international emissions reduction strategy.
The bottom-up INDC approach marks a significant departure from the relatively unsuccessful top-down approach pursued in Kyoto. During the Copenhagen negotiations in 2009, the UNFCCC initiated a movement toward INDCs by inviting nations to submit pledges regarding what they could do to reduce emissions.
The INDC approach acknowledges that countries face different political, financial, and technological constraints that affect national capacity to agree to binding international climate targets. It enables countries to volunteer emissions reductions at politically feasible levels. Countries volunteered significant emissions reductions through this process, but not enough to keep warming below 2°C.
The United Nations Environment Programme (UNEP) rigorously evaluated the 119 INDCs submitted to the UNFCCC before October 1 in its 2015 Emissions Gap Report. According to the report, full implementation of conditional and unconditional INDCs would lead to an emissions gap of about 12 gigatons of carbon dioxide equivalent (GtCO2e) in 2030. If countries that did not submit INDCs by October 1 were to reduce emissions at the same percentage below current policy trajectories as those evaluated in the report, the projected emissions gap would narrow to 11 GtCO2e in 2030.
To stay below the 2°C limit, global carbon dioxide emissions must be reduced to net zero by 2060–75. And total future carbon dioxide emissions must not exceed 1,000 GtCO2e globally. Achieving these levels of emissions reductions will require a substantial increase in worldwide ambition to confront climate change, ambition that goes beyond the INDCs.
What does this mean? Is catastrophic warming inevitable?
Professor Jeffrey Sachs is pessimistic. At the Paris climate talks, Sachs argued that the Paris Agreement is unlikely to result in long-term success. “Setting targets but not developing the means to meet them, does not solve problems,” he said. And James Hansen, the former NASA scientist widely considered the father of climate change awareness, called the agreement “worthless words.”
But according to Achim Steiner, Executive Director of UNEP and Under-Secretary-General of the United Nations, the INDCs represent a real increase in world ambition compared to a business-as-usual scenario, and they are the best we could have hoped for given the inherent complexities of an international negotiation process. Merely preparing INDCs could galvanize climate action that transcends the expected aggregate impact of INDCs, Steiner says.
The Paris Agreement also includes a five-year review mechanism that urges parties to reevaluate and ideally strengthen their INDCs every five years. During negotiations, some delegates expressed hope that the review provision would incentivize countries to increase INDC ambition over time, as clean energy technology improves and becomes less expensive. Such delegates hope that INDCs will eventually become so ambitious that they close the emissions gap. But some commentators criticize the Paris Agreement for lacking a strong enforcement mechanism.
Other commentators, including the World Bank’s former chief economist, Nicholas Stern, argue that it would be practically impossible to make the Paris Agreement internationally enforceable. As Stern noted last week, the international community unfortunately lacks a “police force from Mars and a court from Jupiter.” To strengthen the agreement, Stern suggests implementing international border taxes to disincentivize pollution dumping in other countries.
During country-by-country closing statements at the Paris talks, multiple parties stated their intention to rely on public pressure to ensure that the INDCs are implemented. Writer and professor Elizabeth Kolbert argues that “precisely because the Paris agreement is so short on enforceable actions, the way the world regards it is likely to have a disproportionate impact.” For this reason, Kolbert argues that we should emphasize the agreement’s positive aspects.
Parties will, most likely, seek to clarify the Paris Agreement’s enforceability and five-year review provisions during subsequent negotiations.
According to UNEP’s Steiner, international cooperative agreements (ICIs) with higher ambition than the Paris Agreement may help to close the emissions gap. Already, multinational and subnational groups have formed alliances to reduce emissions at levels ambitious enough to make a dent in the emissions gap. Notable ICIs include the Africa Renewable Energy Initiative, the Under2MOU compact, the Compact of Mayors, and the C40 Cities Climate Leadership Group.
The Under2MOU originated from a partnership between California and the German state of Baden-Württemberg, with the goal of uniting states and regions that are serious about addressing climate change. The partnership unites subnational governments willing to commit to either reducing their greenhouse gas emissions 80–95 percent below 1990 levels by 2050 or achieving a per capita emissions target of less than 2 metric tons by 2050. During the Paris talks, the Under2MOU welcomed 58 new signatories, which brings total membership to 123 jurisdictions that represent more than 720 million people and $19.9 trillion in combined GDP, equivalent to more than a quarter of the global economy.
At an Under2MOU signing ceremony in Paris, California Governor Jerry Brown called on other jurisdictions to join the subnational movement for ambitious climate action. “Climate change presents the opportunity for human beings to rise above narrow parochialism, egoism, and nationalism for the sake of the common good,” he said. “This coalition of the willing is building a global force to reduce carbon emissions and protect the well-being of people everywhere.”
According to Steiner, we may see broader participation in ambitious international cooperative agreements like the Under2MOU partnership as the climate crisis progresses.
Overall, most commentators seem to view the Paris Agreement as a significant step in the right direction, despite the emissions gap. U.S. Secretary of State John Kerry said that the Paris Agreement “sends literally a critical message to the global marketplace.” The agreement has been heralded as a solid “framework,” “starting point,” and “catalyst” for addressing climate change. According to Kolbert, the agreement “changes the presumption that carbon emissions will continue to grow to the presumption that they must soon start coming down.”
Although people disagree about the quality of the Paris Agreement, no one contests that the real work starts now. “Today, we celebrate,” said Miguel Arias Cañete, the European Union’s energy commissioner and top climate negotiator. “Tomorrow, we have to act.”
According to Sandra Steingraber, a prominent American biologist, the process of implementing and scaling up INDCs to close the emissions gap is a herculean task. But she believes that “we can and must be Hercules.” Steingraber urges us to emulate Martha Ferger, a 90-year-old New York resident arrested earlier this year for civil disobedience in protest of hydraulic fracturing.
As Achim Steiner closed his presentation last week, he urged the audience to remain optimistic about our ability to close the emissions gap. “We absolutely must not,” he said, “underestimate the capacity of the world to reinvent itself.”
Sophie Wenzlau is a senior fellow at the Worldwatch Institute and a student at the UC Davis School of Law. Her research focuses on the role of subnational governments in climate change mitigation and adaptation.