“I think one of the informal roles of the states was just to assure other countries around the world that even though American leaders were not supporting Paris, it was more important than ever for the states,” Theoharides said, TODAY president. and CEO of the Trustees of Reservations, a nonprofit land conservation group in Massachusetts.

In an act of history repeating itself, as tens of thousands of world leaders, business interests, climate experts and advocates meet for the annual United Nations climate gathering in Baku, Azerbaijan, This year again, during the summit, everyone will be talking about Donald Trump.

The president-elect will take office in a very different time than in 2017. increasing impacts of extreme weather events fueled by global warming, from wildfires to hurricanes, have become impossible to ignore, while the technology and economics behind global warming. clean energy transition – including solar and wind power, as well as battery storage – have improved significantly.

At the same time, experts say the goal of keeping global temperatures from rising above the critical threshold of 1.5 degrees Celsius (2.7 degrees Fahrenheit) above pre-industrial levels is becoming increasingly unlikely. Beyond that, climate scientists say the risks of more destructive storms, drought, wildfires, heat waves and species extinctions increase significantly.

Trump’s election last week already seems to be sapping momentum ongoing climate negotiations, known as COP29 and is expected to last two weeks, as Trump’s transition team talks about drilling for more oil and ignoring the greenhouse gas emissions that come with it. Trump has called climate change a “hoax” and has often said that reducing the use of fossil fuels will dampen the U.S. economy.

Experts believe that Trump’s return to power will not cause the same shock as eight years ago. When the U.S. government withdrew from the Paris Agreement, other countries – as well as the leaders of American states and cities – followed suit.

Yet there is “growing frustration among many other parties with the inconsistency of the United States, joining, withdrawing, joining and withdrawing.” The unreliability of the United States has become more real,” said Kelly Sims Gallagher, dean of the Fletcher School of Law and Diplomacy at Tufts University.

That could mean that if the United States leaves the Paris Agreement again, as planned, other countries could follow, she said. It could also make it more difficult to try to convince other countries to support a new climate finance plan, which is the main focus of this year’s climate negotiations. If it appears that the world’s largest economy and second-largest emitter of greenhouse gases is unwilling to help finance the impacts of climate change and the transition to clean energy on a global scale, this could put the brakes on efforts elsewhere.

Mindy Lubber, president of Ceres, a Boston-based sustainability advocacy nonprofit, said, “It doesn’t matter who the president is and how strong his position is. But, she added, “I don’t think all has been lost.”

The best proof of this, she says, is to look to the past.

After Trump announced the United States’ withdrawal from the Paris Agreement in 2017, mayors, governors, CEOs, religious leaders and many others reacted almost immediately. They called the movement “We Are Still In,” a declaration of their intention to continue working to achieve climate goals in the United States.

When Theoharides and his peers from across the country participated in climate negotiations in 2017, they were able to show that collectively, their states’ targeted greenhouse gas reductions would reach levels the United States had previously achieved. committed, even without leadership from Washington.

Since its creation, the movement, renamed “America is All In,” has collected more than 3,900 signatures.

At this year’s climate negotiations, it is unclear how strong the presence of local officials will be. No one from the city of Boston or Gov. Maura Healey’s administration will be in attendance, according to spokespeople for both administrations. Political experts in the region said they expect that to change next year, with the Trump administration in power.

This week, U.S. delegates can highlight the progress the Biden administration has made in recent years, said Joseph Curtatone, president of the Climate Transition Alliance. This includes the landmark nnational climate legislation, called the Inflation Reduction Act, which was passed under President Biden’s administration, delivering more than $361 billion in investments in climate and clean energy and more than 300,000 jobs in blue and red states.

It’s not yet clear what will happen to the unused funds from the legislation, which Trump called “the biggest scam in history.” But delegates can assure others in Azerbaijan “This progress cannot be undone,” Curtatone said.

U.S. delegates may also point out that the Biden administration This is something of a welcome historical aberration for the United States. Progress on climate and clean energy has largely occurred at the state and local level.

“Cities and states have been at this for much longer and started much earlier because we see the reality on the ground,” said Brian Swett, chief climate officer for the City of Boston. “We know here in Boston that we have to be leaders if we want other people to be willing to follow.”

Even before Trump’s first election, Boston joined the Carbon Neutral Cities Alliance – a group of 22 cities around the world, including London, Berlin, Melbourne and Amsterdam – that have committed to achieving carbon neutrality within the next 10 years. Next 20 years.

Mayor Michelle Wu is also part of a bipartisan group of nearly 350 mayors across 46 states, known as Climate Mayors, who are committed to climate action. Last week, after Trump’s victory was announced, climate mayors announced: “No matter what, we will fight for the future that Americans demand and deserve, where our communities, our health, our environment and our economy thrive. We will not go back. »

Sabrina Shankman can be contacted at [email protected]. Follow her @shankman.