Mr. Regan informed agency employees that he would leave before the formal end of the Biden term.

© Pete Kiehart for The New York Times

The promise of deeper emissions cuts will very likely be ignored by the Trump administration, but officials hoped it would send a signal to the world.

© Kim Raff for The New York Times

Climate purity is a recipe for failure.

The program will unleash an economic boon, breathing new life into a city still trying to get its bearings post-Covid.

China has now passed Europe in its historical contribution to global warming. Rich nations say the country should contribute more climate aid.

Days ahead of the U.N.’s global negotiations on climate change, China and other developing countries said trade restrictions should be part of the talks.

Food production is concentrated in too few countries, many of which face water shortages, the researchers said.

A surge in power use worldwide could make it harder for nations to slash emissions and keep global warming in check.