Executive orders and announcements by President Trump have put billions of dollars in U.S. climate commitments into question.

On President Trump’s first day in office, he pulled out of the Paris Agreement, a pact among nearly all nations to fight climate change. Reporting from Davos, Switzerland, David Gelles, a climate journalist for The New York Times, explains what this decision means for the rest of the world.

C.E.O.s, policymakers and billionaires at the World Economic Forum’s conference have long pledged to fight climate change. Has it done any good?

Officials and business executives at the annual gathering in Switzerland said the fight against global climate change would continue with or without the United States.

Extreme weather events — deadly heat waves, floods, fires and hurricanes — are the consequences of a warming planet, scientists say.

Sheila Morovati’s Pacific Palisades home was spared, but her neighborhood was decimated in the Los Angeles fires. For her, climate change looms over the tragic losses.

Forty-four years ago, Ronald Reagan took aim at Jimmy Carter’s environmental legacy. President Biden’s climate initiatives could face a similar fate.

Investors are betting that they can make a dent in global warming, and healthy profits, with companies that alter the atmosphere.

Presidents have extraordinary control over climate policy, in part, because it’s been decades since Congress has passed a comprehensive environmental bill.

© Tierney L. Cross for The New York Times