Climate Change Extends Wildfire Hours Across North America

A new study reveals that human-caused climate change is extending the daily window for wildfire activity across North America, diminishing the traditional nighttime breaks that allow firefighters to gain control over blazes. Published Friday in the journal Science Advances, the research by Canadian scientists shows that potential burning hours have increased by 36 percent continent-wide over the past 50 years, with particularly sharp rises in western Canada and parts of the United States.

The analysis, led by researchers from the University of Alberta, Thompson Rivers University and Natural Resources Canada, examined hourly satellite data from nearly 9,000 wildfires between 2017 and 2023. It found that 60 percent of these fires reached peak intensity in less than 24 hours, with 14 percent peaking at night. Using a machine-learning model trained on this data, the team reconstructed historical patterns back to 1975, revealing how warmer, drier nights and mornings are eroding the cooler, more humid conditions that once slowed fire spread.

In British Columbia and Alberta, wildfire seasons now feature 200 to 250 additional hours of fire-conducive weather compared to the 1970s,...