Negotiators from around the world are meeting in Bonn, Germany, to hash out the finer details of the 2015 Paris climate accord.
But the challenges in front of them have been made more fraught by an unknown variable — the Trump administration. If the US abandons its commitments, which Trump has threatened to do, the entire agreement could unravel. And if that happens, the threat of climate change would grow exponentially.
The agreement’s success — and its main point of criticism — hinged on its flexibility. Each country was able to determine its goals and many countries chose to focus on low-hanging fruit. For example, China, the biggest emitter of greenhouse gases, said that it would hit peak emissions by 2030, a time frame that had already been estimated by the US years earlier.
But that flexibility now gives the US an escape route.
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Here are five things to know about the climate talks happening through May 18.
1/ The Rules of the Game
The proposals that countries submitted for the Paris climate accord were not standardized and many of them lack detailed action plans.
The negotiators in Bonn are working to fill in the blanks — figure out how progress will be evaluated, who will do the evaluating, and what mechanisms will be put in place to determine if targets and funding commitments are being met. The negotiators will also determine if the current commitments are sufficient to meet the ultimate goal of the Paris climate accord — keeping temperatures below 1.5 degrees Celsius pre-industrial levels.
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“Robust, coherent rules and processes are needed to make implementation of the Paris agreement effective, fair and equitable,” wrote Paula Caballero, global director of the World Resources Institute’s climate program.
This should have been the bureaucratic equivalent of terms and conditions, but now it’s shrouded in drama.
2/ Will Trump Sabotage the Agreement?
Since becoming US president, Donald Trump has put the Paris climate accord into a state of emergency. The US is central to the arrangement as the second biggest emitter of greenhouse gases in the world, so if Trump cancels the country’s commitments, it could unravel the entire plan.
There are different factions within the Trump administration that argue for opposite routes.
Led by Secretary of State Rex Tillerson and Ivanka Trump, the pro-Paris side argues for staying within the agreement because it gives the US diplomatic leverage. Conversely, abandoning the agreement would let down all the countries of the world and could jeopardize other international ambitions. Further, since the agreement is essentially voluntary, the US could simply fail to fulfill its commitments.
"Politically it would be a disaster; diplomatically it would be a disaster. The whole world would put the US as a pariah," Jeffrey Sachs, from the Center for Sustainable Development, told Al Jazeera.
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The anti-Paris side, led by chief strategist Steve Bannon and EPA director Scott Pruitt, argues that the agreement is burdensome and runs counter to the Trump administration’s priorities — reviving the coal industry and relaxing environmental regulations, for instance. They also argue that staying in the agreement opens the US to lawsuits from environmental groups that will allege the country has failed to uphold its promises.
The Trump administration has already jeopardized the US’s commitments by planning a rewrite of the Clean Power Plan and rolling back other regulations on emissions.
Many observers think that Trump will make a decision on the pact by May 18 and his team is currently discussing what to do, according to White House Press Secretary Sean Spicer.
"We all continue to hope the US will find a way to remain within the Paris agreement and to remain committed to the Paris goals," EU climate commissioner Miguel Arias Cañete, told the BBC.
"Politically it would be a disaster; diplomatically it would be a disaster. The whole world would put the US as a pariah", Jeffrey Sachs, from the Center for Sustainable Development, told Al Jazeera.
3/ Obama Weighed in from Milan
The Obama administration set in motion US involvement in the Paris climate agreement by creating the Clean Power Plan, which aims to reduce power plant emissions, and implementing a range of other measures such as energy efficiency standards, reduced car emissions standards, and more.
Obama also helped to spearhead the entire agreement by encouraging China to join.
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On Tuesday, Obama weighed in on the agreement from a conference in Milan and expressed his optimism.
"The good news is the private sector has already made a determination that the future is clean energy," he said. "Those things are locked in now, into the energy sector. Because of the debates taking place in the current administration the steps may be taken more slowly than they would have been done, but I'm confident.”
"During the course of my presidency, I made climate change a top priority because I believe that of all the challenges that we face, this is the one that will define the contours of this century, more dramatically perhaps than any other," he said.
4/ China Is Taking the Lead
As US leadership on climate change recedes, China is stepping up.
On Tuesday, China’s president Xi Jinping reassured the newly elected president of France Emmanuel Macron that China would protect its climate commitments.
“We should join hands and rise to the challenge,” Xi said earlier in the year at the World Economic Forum. “Let us boost confidence, take actions and work together for a bright future.”
5/ 1.5 Degrees
The negotiators in Bonn are trying to figure out how to keep global temperatures under 1.5 degrees Celsius from pre-industrial levels.
But that limit could be surpassed within nine years, according to a new paper in the journal Geophysical Research Letters.
If that happens, then the core objective of the Paris climate accords would be shattered. The world would then fall back to the secondary goal of keeping temperatures to under 2 degrees Celsius.
“In the first year at 1.5C, events like flooding, drought and other extreme weather may not be very much different from now,” Professor Richard Betts, a Met Office fellow and chair of climate impacts at Exeter University, told the Independent. “But as the world warms further, longer-term effects will become apparent, especially ongoing sea level rise as glaciers continue to melt.
“The full impacts will take decades to play out, but once set in motion they could be hard to reverse,” he said.