One area sure to be upended by a second Trump presidency is environmental and climate policy. President-elect Donald Trump has pledged to roll back myriad environmental regulations and refocus America’s energy policy on the fossil fuels that are driving the climate crisis. In this Q&A, UCLA School of Law experts Cara Horowitz and Ann Carlson weigh in on the possible impacts.

Horowitz is executive director of the Emmett Institute on Climate Change and the Environment, where she directs the Frank G. Wells Environmental Law Clinic, which recently celebrated 30 years of training law students. Carlson is the Shirley Shapiro Professor of Environmental Law and formerly served as acting administrator for the National Highway Traffic Safety Administration in the Biden administration.

During the first Trump administration, California played a pivotal role leading state resistance to federal policies. How is California poised to do that again?

Cara Horowitz: I have no doubt that California will once again lead a robust set of efforts to push back against environmental rollbacks and keep momentum where it can. It will play a major role in the international community as an active participant in climate talks. It will lead by example with strong state climate policies on issues like renewable energy and transportation. It will coordinate with others inside and outside the U.S. to fill the vacuum created by lack of federal leadership, including via its ongoing partnerships with China. And it won't shy away from taking the Trump administration to court when necessary to enforce the rule of law.

One of the first acts of a new president is selecting a cabinet. What nominations, appointments and other personnel actions are you watching?

Ann Carlson: I’m watching for whether appointees to agencies like EPA have serious experience in the federal government. It turns out that governing – even in an anti-regulatory fashion as Trump has committed to – is complex, technically challenging work. In rolling regulations back, for example, an agency has to show why it is doing so with real evidence, it has to follow the law, and it has to follow processes like public notice and comment. The first Trump administration made numerous mistakes in trying to implement its policies and it lost repeatedly in court. Without experienced leadership we are likely to see a repeat of the first term.

The courts have been a battleground for environmental regulations in recent years. How will a Trump administration change the trajectory of this litigation?

Horowitz: If the last Trump administration is any guide, Trump's next administration will fail to conform to basic requirements of U.S. federal environmental law, including the Clean Air Act, the Clean Water Act and likely now the Inflation Reduction Act and will try to diminish their importance. It will once again fall to nonprofit environmental groups and to states like California to hold this administration to account and to enforce the minimum requirements of environmental law, through the courts and through litigation.

The last Trump administration had a pretty dismal litigation record in environmental cases, often losing; we'll have to see whether the same holds true in Trump 2.0. Courts could once again be very important in efforts to slow down environmental rollbacks, for example — but we'll have to see how changes to the federal judiciary since 2016 play out and affect these efforts.

The clean energy transition is well underway and has been encouraged by laws like the Inflation Reduction Act and other Biden administration policies. What impact will a new Trump administration have on that transition?

Carlson: The Trump administration cannot derail the transition to clean energy. To be sure, it can slow it down. But the renewable energy sector is booming – 40 percent of our electricity generation now comes from renewable sources. Solar and wind energy are cheap. Globally, 80 percent of new energy generation is from resources like solar and wind. The transportation sector is electrifying, with automakers offering 117 new electric vehicle models to consumers, making massive investments in transitioning to EVs and making those investments in the United States. The global push is even bigger, especially in Europe and China. Again, Trump can slow things down, but we aren’t returning to the days of fossil fuel dominance.

Trump has talked about again withdrawing the U.S. from international climate commitments. How could this play out?

Horowitz: The Paris Agreement is the primary platform for organizing international cooperation on climate change. The agreement isn't perfect, but it has resulted in a remarkable range of actions by countries around the globe to reduce emissions and to pledge support to nations most vulnerable to climate harms. Trump's team has said that he is considering withdrawing from the agreement, which he can do through executive action and which would become effective one year after Trump gives notice of intent to withdraw. Withdrawing from the agreement would mean that the U.S. no longer has a seat at the table on Paris Agreement negotiations and decision-making. It would rob the U.S. of power to shape global outcomes and would, even more troublingly, send a strong signal to other countries that the U.S. is uninterested in working together to solve this global problem. And perhaps most troubling of all, it would cede global leadership on climate change to China.

Apparently, Trump's team is considering going even further, by withdrawing the U.S. from the 30-year-old (United Nations) Framework Convention on Climate Change, the foundational document on which global climate cooperation is based. That would be a truly radical act that would isolate us on the world stage in unprecedented ways.