After the U.S.-China Pact, Will the World Pick a Peak Carbon Date?

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Last week the world’s two biggest greenhouse gas emitters, accounting for 40 percent of global emissions, signed an accord on improving their polluting ways. The U.S. said it would reduce emissions as much as 28 percent below 2005 levels by 2025, while China said its emissions would reach a maximum no later than 2030 and that the country would ramp up renewable energy production.

The deal doesn’t mean the climate crisis is over. Just look at a country such as Canada: It abandoned legally binding commitments to reduce emissions under the 1997 Kyoto Protocol, demonstrating that countries don’t always meet their firmest promises in this area. Even if the U.S. and China do hold to the agreement, it’s not enough by itself to stave off considerable climate change by the end of the century. But it is a hopeful step. And it suggests the possibility that the world could agree to a global peak carbon date as part of climate negotiations next year in Paris.

In December 2015, world leaders will meet in France’s capital to agree on a follow-up to the Kyoto Protocol. Paris almost certainly won’t involve a new global treaty—not least because its chances of passing the U.S. Senate would be infinitesimal. But there’s hope the agreement will involve a lot more countries making commitments than they did at Kyoto—including the U.S. plus China and the rest of the developing world.

To date, Chinese and U.S. intransigence has been the major problem in forging a global deal on climate. Europe has already agreed to emissions 40 percent below the 1990 level by 2030. The agreement struck between the U.S. and China last week puts pressure on India—the world’s No. 3 emitter—to move beyond its promises and agree to a peak carbon year of its own. Brazil might follow suit, especially as its emissions are already falling because of slowed deforestation.

Some of the poorest parts of the world will likely see peak carbon occurring considerably later than China. To provide decent standards of living around light, heat, cooking, transport, and communication, most African nations need to increase their energy consumption by orders of magnitude. Using the most cost-effective technologies, that would require considerable increases in greenhouse gas emissions.

But the earlier that richer countries commit to a peak in their emissions, the greater the incentive for technology development that reduces the cost of renewable power. That will help African nations reach peak carbon earlier without slowing their development. For China to stick to the deal with the U.S. on renewable energy production, it will have to deploy at least 800 gigawatts of wind, hydro, solar, and nuclear capacity by 2030—about the same as total electricity capacity in the U.S. today. That massive potential demand should spur considerable research and development efforts.

The hope for progress among many of the world’s largest emitters also provides grounds for optimism for a better global target on climate progress. At the moment, world leaders have agreed only to prevent global average temperatures from climbing by more than 2 degrees centigrade by the end of the century. That target has been looking increasingly unlikely as the years pass and greenhouse gas emissions keep climbing. But it is inadequate for other reasons, which are laid out in a report by Nigel Purvis of Climate Advisors. For one, the science isn’t clear on what emissions path would guarantee staying below 2 degrees. The temptation with such a target is for leaders to put off action until the last moment—which would be some time from now, since the end of the century is 85 years away.

The U.S.-China agreement suggests the potential for a new global peak carbon target—the year by which worldwide greenhouse gas emissions will start to decline. This global target year (Purvis suggests it could be 2025) could build on an aggregation and extension of the national commitments made in the runup to Paris. The global peak would be a nonbinding aspirational figure, and it would not add any specific national accountability above the national targets.

But a nonbinding target can still be useful to legitimize and motivate action while holding leaders to account—especially if the target is 10 or 15 years off rather than 85 years away. And an agreement on a peak year would provide some optimism that the world is at last starting to respond to the climate crisis in earnest. If the Chinese-American deal makes that possible, Christmas might come a little early to climate advocates spending December in Paris next year.

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