Surging emissions from wildfires may have been behind the increase, which was the largest since modern measurements began more than half a century ago.

© Bryan Anselm for The New York Times

Recent rain significantly reduced the risk of a large fire breaking out before year’s end, experts said.

© Samantha Lindberg/Mammoth Lakes Tourism

It seemed that last year’s wildfire in Los Angeles had been extinguished safely after two days. But it had just gone underground.

The rare October storm could cause mudslides and debris flow, forecasters said. Some residents in Los Angeles County have been told to evacuate.

© Noah Berger/Associated Press

Readers respond to a guest essay about vaccine debates. Also: Attorney General Pam Bondi’s performance; wildfire smoke and our health.

At the Climate Forward live event, we spoke to top policymakers about China, the Trump effect on climate policy and the boom in artificial intelligence.

Across the country, unmasked wildfire fighters are falling ill and dying. Hannah Dreier talks about her investigation into the risks these workers face.