Governor Jerry Brown of California speaks about his goals for the climate summit in San Francisco on Monday.Rich Pedroncelli / AP

In his 20 months in office, President Donald Trump has stripped out huge swaths of federal climate policy. He has canceled or incapacitated Barack Obama–era programs meant to encourage a cleaner electricity system and more efficient cars, and he has left the Paris Agreement on climate change.

Now climate-concerned governors are doing what they can to fight back.

On Thursday, a bipartisan alliance of 17 governors announced a new set of policies aimed at combatting climate change and working around Trump-led rollbacks. They have promised to better manage natural land; to blunt the effect of solar-panel import tariffs; and to restrict the release of “short-lived climate pollutants,” gases like methane that can trap enormous amounts of heat in the atmosphere.

The governors also pledged to spend $1.4 billion to build new infrastructure for electric cars and to support their purchase, deploying funds that were won in the class-action settlement with Volkswagen.

Not all of their plans are accompanied by such hefty funding. But the slate of new policies, taken together, represents one of the broadest set of actions yet taken to keep carbon emissions falling in the face of the Trump administration’s rollbacks.

The announcement was all the more notable for being made with the governments of Mexico and Canada, which agreed to implement their own version of some of the state-level policies.

“This is a statement of confidence that we can lick this problem,” Jay Inslee, the governor of Washington and a Democrat, told me. “We have to fight the despair that some people feel because of the Trump administration’s climate denial and lack of planning. We have to defeat that.”

“If man is going to destroy our fellow man, it’s either going to be by nuclear proliferation or because we ignore the simple reality that our environment is getting warmer, it’s going to overwhelm us, and we are approaching a tipping point,” said Dannel Malloy, the Democratic governor of Connecticut, at the Thursday event. “We simply need to do everything in our individual power and as states together to hold that back.”

The governors are acting as members of the U.S. Climate Alliance, a coalition of states that have promised to abide by the Paris Agreement on climate change. The alliance is made up of 14 Democratic governors, including Ricardo Rosselló of Puerto Rico, and three popular Republican governors from traditionally blue states: Larry Hogan of Maryland, Charlie Baker of Massachusetts, and Phil Scott of Vermont.

They issued the new policies at the Global Climate Action Summit in San Francisco, a conference of countries, companies, and local governments that have committed to fighting climate change. Part pep rally, part technology exhibition, the summit is meant to inspire flagging environmental hopes while celebrating the legacy of Jerry Brown, California’s outgoing Democratic governor, who has helped turn the state into a climate-policy powerhouse.

The summit is also global recognition that state and city governments are, for now, the sole hope for aggressive American climate policy. The U.S. Climate Alliance is the star of that show: It is by far the largest coalition to emerge since Trump took office. Taken together, the 16 states in the alliance represent 40 percent of the U.S. population and roughly half of its GDP.

But the alliance also represents the pitfalls of a subnational approach. Despite essentially forming the world’s third-largest economy, the 16 Climate Alliance states represent only a quarter of U.S. carbon emissions, according to 2015 data from the Energy Information Administration.

So it remains an open question how successfully states and cities can fight climate change, especially if the federal government pushes the other way. A recent Yale report found that the current slate of state and local policies would only get the United States half of the way to meeting its 2030 carbon-cutting promises under the Paris Agreement.

The Thursday announcement encompassed five policies, several of which have been described before. Some of them are targeted directly at Trump’s actions.

Earlier this week, for instance, the Trump administration began rolling back Environmental Protection Agency rules restricting methane emissions. Methane is a powerful greenhouse gas: A single molecule of methane can trap roughly 25 times as much heat as a molecule of carbon dioxide, even though the methane leaves the atmosphere faster.

As part of the Climate Alliance announcement, the 16 states resolved to reduce their emission of methane and other short-lived super-pollutants by 40 percent by 2030. The governments of Mexico and Canada joined them in making this pledge.

“It’s pretty remarkable to have the governments of Mexico and Canada issuing a statement with 17 U.S. governors, as opposed to the federal government,” says Dan Lashof, the director of the World Resources Institute in the United States. “That is not normal—and in this particular instance, it’s a very positive thing.”

Also in opposition to Trump, the states promised to implement a suite of utility policies that will reduce the costs of new solar-panel installation. After Trump imposed an import tariff on solar panels earlier this year, U.S. companies froze or canceled $2.5 billion in new large-scale solar projects.

“There’s a lot of tertiary or supply-chain ways we think states can continue to drive down the [solar] costs,” Inslee told me.

The states also pledged to adopt the same strict energy-efficiency guidelines for household appliances, which it says will save consumers $4 billion by 2025. Trump’s Energy Department has sometimes neglected or tried to close similar federal programs, such as Energy Star.

But some state programs seem to have little to do with the president. For instance, the governors pledged to better track how carbon dioxide is stored in ecosystems and soil. Forests in the United States absorb more carbon than they emit, offsetting 11 percent of the country’s greenhouse-gas emissions. But neither states nor the federal government have ever focused on better managing that bounty, Lashof told me.

Land use “is an area where we just aren’t doing a good enough job of tracking what’s going on,” he said.

David Ige, the Democratic governor of Hawaii, told me that the new land-use strategy was the most important policy to his state. He said that he looked forward to his state’s land managers sharing their expertise and learning from those in other states.

“In Hawaii, our people are connected to the land. And better managing nature and our working lands is just fundamentally a part of our culture,” he said. “We want to know what other states are doing, and we want to understand how to do it better.”

“A lot of these things—if you’re not a climate-policy wonk, then they seem really unsexy,” says Julie Cerqueira, the director of the U.S. Climate Alliance. “But if you have a handful of states that adopt the same energy-efficiency standards, you’re pushing the entire market in that direction, even if 30 other states don’t have these rules.”

“These are important actions to rein in emissions and many explicitly respond to our Trumpian woes,” said Julian NoiseCat, a policy analyst at the climate-activist group 350.org, in an email. “The most significant announcement, in my view, is the $1.4 billion from the VW settlement. We need as much investment in transforming our energy and transportation sector as we can get.”

“It’s important, though I admit discouraging, to point out that $1.4 billion is a great commitment, but we need much more. The Second Avenue Subway in New York City, for reference, cost $17 billion,” he added, referencing a famously expensive transit project.

“These are technical policies, but this is where the rubber meets the road. It’s a lot of real-life, meat-and-potatoes action, and it’s not just pronouncements of intent,” Governor Inslee said.

“Trump can’t stop us in the state. He can’t stop us from having a clean energy fund. He can’t stop me from moving forward to incentivize electric cars. He can’t stop us from continuing with our renewable portfolio standards. And that’s an important statement—he can tweet til the cows come home, but he can’t stop us from adopting statewide policies,” he added.

“And that’s important, right now, for both the nation’s vision and its mental health.”

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