New Delhi, April 18 -- Burning time for North American wildfires is going into overtime. Flames are lasting later into the night and starting earlier in the morning because human-caused climate change is extending the hotter and drier conditions that feed fires, a new study found.

Fires used to die down or even die out at night as temperatures dropped and humidity increased, but that's happening less often. The number of hours in North America when the weather is favorable for wildfires is 36% higher than 50 years ago, according to a study Friday in Science Advances.

Places such as California have 550 more potential burning hours than the mid-1970s. Parts of southwestern New Mexico and central Arizona are seeing as much as 2,000 more ho...