One week ago, the Salata Institute for Climate and Sustainability at Harvard University published an essay I wrote for its Climate Blog. My topic was “What Trump’s expected exit from the Paris Agreement will mean.” In fact, Trump filed papers yesterday with the United Nations to initiate the process of withdrawal. Hence, my essay from last week is (unfortunately) very relevant, and so I’m reproducing it in full here for readers of my blog, An Economic View of the Environment.
What Trump’s expected exit from the Paris Agreement will mean
Jan 13, 2025
By Robert N. Stavins
At noon on Monday, January 20, Donald Trump will take the oath of office for his second term as president. It is reasonable to anticipate that one of his first actions will be to file papers with the United Nations to initiate withdrawing the United States from the Paris Agreement of 2015.
In short, it may be 2017 all over again, when Trump moved to exit the agreement – a legally binding accord requiring signatories to publish plans for reducing planet-warming emissions. As I wrote at the time, the Paris Agreement included an initial statutory delay of four years from the date of the agreement coming into force in November 2016, meaning the U.S. remained a party for almost the entirety of Trump’s first term. Dedicated staff from the State Department continued to participate in the ongoing negotiations in meaningful ways, including co-chairing with China the Enhanced Transparency Framework negotiating stream. Ultimately, the U.S. was out of the Paris Agreement for just a few months – until shortly after President Biden’s inauguration in early 2021.
Today, the statutory delay is 12 months, and so if Trump files withdrawal papers as soon as January 20, one year later the U.S. will be alone among the community of major nations as a non-party to this fundamental and path-breaking agreement (only Iran, Libya, and Yemen are non-parties of the agreement). Furthermore, it is much less likely that civil service staffers at the State Department, Environmental Protection Agency, or the Department of Energy will be able to continue their work, as Trump now seems determined to purge the upper ranks of the Executive Branch of anyone other than loyalists. At the very least, the U.S. delegation will have lame duck status for the year.
A possible – but unlikely – alternative to withdrawal
It is at least conceivable that instead of withdrawing, the Trump administration could choose to submit to the UN a revised and severely downgraded climate action plan as required under Paris – the Nationally Determined Contribution (NDC) – although a subsequent administration could unilaterally revise the NDC again. The option to downgrade the NDC rather than withdraw existed during Trump’s first term as well, but was obviously not chosen.
Whereas the original Obama-era NDC pledged to reduce U.S. emissions by 26-28% below 2005 levels by 2025, Biden updated this in April 2021 to 50-52% by 2030, and on December 19, 2024, the lame-duck Biden administration strengthened this to 61-66% by 2035. But it is highly unlikely the Trump administration would want to submit a downgraded NDC, given that such action could be interpreted as endorsing the overall legitimacy of the Paris Agreement, anathema to MAGA Republicans.
And an even more dramatic route
A more drastic action would be to withdraw not just from the Paris Agreement, but from the umbrella agreement, the 1992 United Nations Framework Convention on Climate Change (UNFCCC). This requires only a one-year delay to become effective. During Trump’s first term, serious consideration was never given to this more significant move, perhaps because the UNFCCC was ratified by the Senate in 1992 and signed by Republican President George H.W. Bush.
Now, however, some of the most passionate climate skeptics in Trump’s orbit want the U.S. to pull out of the UNFCCC as well. A key question, which legal scholars can debate, is whether withdrawal from a Senate-confirmed treaty requires Senate action, including a super-majority vote, which Democrats in the chamber could easily defeat. There seems to be some uncertainty. While Senate action is required to ratify treaties, Senate involvement in terminating ratified treaties is not mandated nor even mentioned in the Constitution. Several previous presidents have unilaterally exited from Senate-confirmed treaties.
Global impacts
In the meantime, a key question is how a U.S. withdrawal will impact other key countries’ positions. We know that after Trump’s first-term pullout the EU became more ambitious; China was happy to evolve from co-leadership with the U.S. to sole leadership; India did not retrench; and although Brazil backed off its pledge, that was because of the election of Jair Bolsonaro, himself a climate skeptic.
It may be that Trump’s election need not derail global climate action, but it is too soon to make firm predictions. It does appear that Trump’s November election victory emboldened Saudi Arabia to be much more strident in its defense of fossil fuels weeks later at COP29, even more than it had been previously at this annual meeting of UNFCCC signatories. The result, largely due to Saudi Arabia fighting any negative comments about fossil fuels in the final communique, was that COP29 did not repeat a call for a transition away from fossil fuels, let alone offer something stronger. EU and the U.S. negotiators wanted language about actions to achieve any goal, but that was likewise rejected. If, beginning in January 2026, the U.S. is not even a party, the negotiating effectiveness of countries such as Saudi Arabia will, if anything, be enhanced.
Finally, some may wonder what a U.S. exit will mean for the world of climate finance (who pays for climate damages and the energy transition – and how). It is helpful to recall that COP29 was labeled the “Finance COP,” because it was intended to focus on augmenting developed countries’ commitment made in 2009 (at COP15 in Copenhagen) to mobilize $100 billion per year by 2020 to support developing countries in addressing climate change, both for mitigation and adaptation. That commitment was eventually reached two years late. At COP29 developing countries received pledges of $300 billion annually, less than 25% what they sought. Will other donor countries fill a void created by U.S. withdrawal, or will it weaken others’ resolve to supply climate finance to developing countries? It will be some time before we know.
Bottom line
All in all, the real-world implications of the expected, forthcoming withdrawal of the U.S. from the Paris Agreement under Trump 2.0 may turn out to be less consequential than some observers have feared, despite the clear abdication of global leadership, and the great disappointment that will surely be felt by many in government, environmental advocacy, academia, and private industry. By far, the greater climate policy consequences will be in terms of extensive and severe downgrading of U.S. domestic climate and energy policy, whether via legislation, regulation, or both.
