SACRAMENTO, United States, Aug. 8 (Xinhua) -- California's wildfire season starts far earlier than decades ago, giving fires more dry days to spread long before the peak summer heat, a new study has found.
The study, titled "Anthropogenic warming drives earlier wildfire season onset in California," published in Science Advances on Wednesday, analyzed about 2.3 million wildfire records between 1992 and 2020 and found that most regions in the most populous U.S. state have seen earlier wildfire activity and lengthening fire seasons. In parts of the northern mountains, the season now begins more than 10 weeks earlier than in the 1990s.
Researchers attribute these changes mainly to warmer springs, while human-caused warming alone has advanced the onset of wildfire seasons by six to 46 days statewide during the period.
Early wildfire ignitions have major consequences. Historical data indicate that once the fire season begins, the cumulative area burned increases rapidly, particularly between June and July, a trend consistent across regions despite varying percentages, according to the study.
The study also linked earlier fire season onsets to larger average fire sizes later in the summer, underscoring the mounting risks posed by climate change-driven shifts in fire behavior. ■
