President-elect Joe Biden has promised to rejoin the Paris Agreement, an international climate accord adopted in December 2015, on his first day in office.

Under the agreement’s rules, that means the U.S. will again become a party to the accord just months after the Trump administration’s bid to leave it became final on November 4. In the years since the U.S. signed the agreement, the Trump administration has stepped away from international climate negotiations while loosening domestic environmental rules.

With Biden and Vice President-elect Kamala Harris soon to be in charge, the few months the U.S. spends entirely outside of the parameters agreement amount to a “speed bump,” said Alden Meyer, former director of strategy and policy for the Union of Concerned Scientists, who has attended U.N. climate negotiations since the 1990s. But once the U.S. is back in, he said, the question then becomes how the U.S. lives up to "what would be expected from a world leader on the issue.”

That means the Biden administration will need to rebuild international trust in U.S. climate ambition, not only by significantly ratcheting up the nation’s targets but also by enacting policies that will drive emissions cuts. Encouraging further decarbonization of the power sector will play a pivotal role.

The U.S. and the Paris Agreement, four years later

Much has changed in the global climate and energy policy landscape since many countries signed the Paris Agreement in 2016, and since the Trump administration vowed to pull out of it. 

In the U.S., cities, states and corporations have filled in some of the gaps left by the Trump administration’s antagonism toward environmental regulation.

Groups such as We Are Still In and America’s Pledge, formed by governors, colleges, cities and other stakeholders, sought to demonstrate to the international community that even as the federal government loosened environmental regulations, businesses and subnational governments were working to uphold them. Analyses from those groups show that U.S. actors still committed to the Paris Agreement encompass nearly 70 percent of the country’s GDP and produce more than half its emissions.

Though the U.S. is far from reaching its Paris commitment — called a "nationally determined contribution" — to cut emissions by 26 to 28 percent below 2005 levels by 2025, those groups say that the subnational commitments now in place could build to a reduction of 37 percent below 2005 levels by 2030. 

“Emissions in the United States in multiple sectors are decreasing as a result of the work of these actors, which is not something I would have predicted when President Trump was elected,” said Elan Strait, currently director of U.S. climate campaigns at World Wildlife Fund and who also helped negotiate the Paris Agreement while at the State Department.

Some of those efforts have helped negate fears that the United States leaving the agreement would cause international “backsliding,” said John E. Morton, a partner at climate investment firm Pollination Group who served as White House senior director for energy and climate change under President Obama.

In recent months, China and Japan have announced long-range goals to reach net-zero carbon emissions. Those are significant steps, albeit ones that still require more details to be hashed out and which must proceed along a shorter timeline to avert the worst climate outcomes, according to several of the former U.S. government officials that spoke to Greentech Media for this story.

“Countries now see it as in their political and economic self-interest to commit themselves to…profound decarbonization,” said Morton. “They think it’s not just the right thing to do but a prudent economic and financial thing to do.”

Nations that are still working under the Paris Agreement are required to submit new, strengthened 2030 targets before the end of this year. Whether countries submit targets that are more ambitious in scope will set the tone for the next stage of Paris Agreement implementation. Tracking from the World Resources Institute shows that 130 countries representing about 45 percent of global emissions have signaled intentions to increase the level of ambition in their new targets.

Morton believes guidance at the federal level in the U.S. will in turn compel greater action from corporations, whose pledges have been voluntary.  

“We're going to see, I think, in sector after sector, companies that have been biting their tongue or holding back because they fear being on the wrong side of a presidential tweet [will] embrace the type of forward-looking, low-carbon direction that President-elect Biden and Vice President-elect Harris are going to be steering the economy [toward],” he said. “The tailwinds that are behind the Biden and Harris climate policy are different from any other winds that any incoming administration has had before.”

Meeting the Paris Agreement challenge

In 2015, the United States delegation played a central role in negotiating toward a consensus on the agreement. Trump campaigned on leaving it. 

"There is a lot of concern in the international community on the whipsaw of U.S. policy on climate,” said Alan Yu, director of international climate policy at the Center for American Progress, who served as the Department of Energy’s director of Asian affairs from 2014 to 2018.

As the U.S. rejoins the agreement, experts said the country will have to recognize all that’s changed, including the stark fact of its own years-long absence. That means bringing humility to the negotiating table.

“There’s no doubt that having the U.S. back, engaged and providing leadership with both its economic clout and its diplomatic machinery…is going to be welcomed and make a major contribution. But it’s not going to be helpful if the U.S. comes back in to say, 'We’re back to save the show,'” said Meyer. “This is a moment for shared leadership, not U.S. exceptionalism.”

The United States will also have to make quick work of its emission-reduction efforts. The Paris Agreement intended to help countries limit warming to 1.5 degrees Celsius, but countries did not collectively commit to the degree of emissions cuts to actually ensure that goal would be reached.

As of 2019, the U.S. had only reduced emissions 12.3 percent from 2005 levels, according to analysis from the Rhodium Group. An economic slowdown tied to the coronavirus pandemic has spurred global emissions reductions in 2020, but only temporarily.  

Biden has named climate change as one of four top priorities for his administration. His transition team announced on Monday that former Secretary of State John Kerry will take on the role of climate envoy.

The next challenge looming for the administration will be the 2030 target it chooses to bring to the international climate summit slated to be held in Glasgow, Scotland next year.

"Setting the right north star, or goal, is critical," said Aimee Barnes, who currently runs climate and energy consultancy Hua Nani Partners and helped launch the U.S. Climate Alliance as a senior adviser to former California Governor Jerry Brown. "We’re going to be stepping into an international dynamic where...the U.S. has been on the sidelines for the past four years and other countries have moved forward. We’ll need to rebuild trust and credibility. Critical to that will be demonstrating our own science-aligned ambition for what we’ll achieve here at home.”

Potential for the most ambitious energy and climate action hangs on the outcome of the runoff Senate races in Georgia. But there are a few ways Biden can draw down emissions without Congress.

Most discussed is the process of what World Wildlife Fund's Strait calls “rolling back the rollbacks.” Biden is likely to rework Obama regulations governing methane, appliance efficiency and auto emissions standards that were undone by the Trump administration.  

Industry, which has historically opposed environmental rules, is likely to back these changes, according to Pollination Group's Morton. Oil companies did not support Trump’s rollback of methane regulations. And on Monday, General Motors withdrew its support for the current administration’s challenges to California’s auto emissions standards.  

The Biden administration could also impose more scrutiny upon the private sector, requiring an accounting of climate risk and transparency around emissions through the Securities and Exchange Commission.

Both Strait and Meyer noted the need for climate and energy-related provisions as part of future stimulus funding. Numerous advocates have floated infrastructure, agriculture and transportation bills as areas where bipartisan consensus may foster some sort of climate policy.

“What I would like to see from a new administration is a combination of acting urgently and quickly where possible, and at the same time doing the work to build the coalition of actors that are going to result in good, sustainable policy that’s not going to get overturned in the next administration,” said Strait.

Within the context of climate negotiations, the U.S. also still owes two-thirds of the $3 billion commitment President Obama made to the Green Climate Fund, which supports climate action in less-developed countries. Part of winning back legitimacy in multilateral climate talks will be reestablishing those lines of support.

“There's reason for trepidation on the international side, but...the international counterparts that I talked to are all very enthusiastic and supportive of Biden...bringing the United States back into the fold on the international climate [talks],” said Yu.