Climate negotiators gathering in Bonn, Germany, this week must grapple with the fact that the carbon age still hasn't peaked.
After plateauing for three years, global CO2 emissions increased in 2017 by 1.4 percent, to a record 32.5 gigatons, according to the International Energy Agency. The European Union, China, and India all registered a hefty increase in emissions, but in the United States, they dropped, despite the Trump administration's pro-coal agenda.
Overall, the global increase is bad news for communities trying to adapt to climate extremes caused by heat-trapping pollution. It also raises the stakes at the current round of climate talks under the United Nations Framework Convention on Climate Change in Bonn this week, where the focus is on on finalizing the rulebook for the Paris Agreement's goal of limiting global warming to less than two degrees Celsius.
The remaining questions about the rulebook are big ones: Who will count and verify carbon emissions? What will assessments of emission-reduction measures look like? How will we know that we've finally bent the global emissions curve downward for good?
Last year's jump in CO2 emissions increases the pressure on the climate negotiators because it puts the most ambitious target of limiting warming to 1.5 degrees Celsius farther out of reach. Hitting that goal would require a 70 to 90 percent reduction of emissions by 2050 (from 2010 levels), according to Climate Analytics, a non-profit climate think tank. And that will become nearly impossible if emissions continue to go up for just a few more years.
The global emissions increase in 2017 was driven by increased energy demand from the rapidly growing economies of India and China, showing that economic growth and carbon emissions have not yet been completely decoupled, says Glen Peters, a climate expert with the Global Carbon Project, a non-profit think tank that closely tracks the world's CO2 budget. But both countries are headed in that direction. China's economy grew by 7 percent in 2017, while its emissions grew by just 1.7 percent.
Notable was the contrast, highlighted in the IEA report, between emissions in the U.S. and the E.U., Peters says. Despite a year-long pro-fossil fuel propaganda campaign by the government, U.S. emissions dropped in 2017 by 0.5 percent (32 million tons); the E.U., which talks a good climate game, saw emissions increase by 1.5 percent last year.
Regarding the one-year comparison between emissions in the U.S. vs. the E.U., Peters says that, while it doesn't tell the whole story, the comparison is a clarifying piece of that story, and demonstrates that market incentives can be just as important as policies and regulations.
The U.S. emissions decline was bigger than in any other major developed economy, mainly thanks to rapid deployment of renewable energy sources, including in red states like Texas and Kansas. But that may change in the future, pending the outcome of current efforts to encourage expanded oil and gas drilling, as well as coal production, and to roll back anti-pollution measures like auto efficiency standards and the Clean Power Plan.
"The damage may not come for a few years in the U.S.," Peters says. "The changes to regulations on oil and gas extraction could take years to take effect." At the same time, he notes that some of the U.S. emissions reductions in the past decade did not come from climate policy, but were driven by simple energy economics: the declining price of wind and solar.
Recent adjustments to the E.U. emissions system should start raising the price of carbon by 2020, leading to bigger CO2 cuts, and individual European countries have announced an ambitious slew of initiatives to make much deeper cuts in the years ahead.
The United Kingdom, for example, is aiming for net zero carbon by 2050; Norway wants to electrify all domestic flights by 2040, and a group of seven major European countries, including France, agreed in advance of the Bonn negotiations to enact a more ambitious European climate policy that would include big emissions cuts by 2030 to reach the Paris target.
But those good intentions are partly at the mercy of the E.U.'s unwieldy decision-making process.
"The E.U. is a slave to its weakest link, and that's Poland. Your climate policy can only be as strong as Poland will allow, and that's going to make things harder," Peters says.
Poland still relies heavily on coal to keep its economy growing, and there's no sign of a significant short-term shift in that country's energy policy. The real debate for Europe is about goals for 2030, since the bloc has essentially already met its 2020 target, Peters adds.
One year's worth of data doesn't necessarily indicate a trend, so we shouldn't overhype the 2017 drop in U.S. emissions, Kelly Levin, a climate analyst with the World Resources Institute, tells Pacific Standard.
"If you look behind the numbers, the pace of decline certainly slowed in the U.S.; CO2 emissions from energy production fell at half the rate of the 2005–16 average. This 2017 blip may not be indicative for what's coming in the U.S.," Levin says, explaining that the drop from emissions in the power sector masks increases from transport, industry, and aviation.
Overall, the U.S. Energy Information Administration projects U.S. emissions will increase by 1 percent in 2018, which is is a big deal, because the U.S. is still the second-biggest global emitter after China, responsible for 14 percent of all global greenhouse gas emissions.
But the pro-coal push by the current U.S. government may be more sound and fury than anything else, according to Susanne Droege, an energy and climate policy expert with the German Institute for International and Security Affairs.
"[President Donald] Trump isn't really getting anywhere with coal revival. Producing more coal-fired electricity is not happening on any large scale," Droege says.
The global push to cut emissions may also hit an obstacle in November, when Poland hosts the COP 24 talks, the penultimate UNFCCC session as the earliest deadlines for mitigation, financing, and stock-taking under the Paris Agreement approach in 2020.
According to Droege, there is some concern that Poland's current nationalistic path will be reflected in a continued pro-coal climate policy that could hinder E.U.-wide efforts toward more ambitious reductions.
And since it will be tough for the world to reach its global climate goals if U.S. emissions were to soar over the next few years, the American negotiating team will once again be scrutinized for clues as to the direction of U.S. climate and energy policy—especially after speculation that French President Emmanuel Macron may be able to woo Trump back into the climate deal.