Wildfires Increasing in Size and Quantity in Eastern U.S., Study Finds

While major wildfires in the U.S. have typically afflicted the west coast in recent years, a a new study based on data from over 30 years has found an increase in the size and frequency of wildfires on the opposite side of the country.

The study, published in Geophysical Research Letters, reviewed large wildfires, over 200 hectares, in Eastern Temperate Forests in the U.S. In the 36 years of data, the scientists found that large wildfires were increasing in size, frequency, number and amount of land burned in southern and eastern parts of the forests studied, while large wildfires were declining in northern parts of the Eastern Temperate Forests.

“It’s a serious issue that people aren’t paying enough attention to: We have a rising incidence of wildfires across several regions of the U.S., not only in the West,” Victoria Donovan, lead author of the study and an assistant professor of forest management at the University of Florida’s Institute of Food and Agricultural Sciences West Florida Research and Education Center, said in a statement. “We’re allocating the majority of resources to fire suppression in the western part of the country, but we have evidence that other areas are going to need resources, too.”

Researchers reviewed the Monitoring Trends in Burn Severity Database, a federal database, for 1984 to 2020. In addition to finding increases in frequency and size of fires in the Eastern Temperate Forests, the study authors also found shifts in seasonality, with large wildfires most common in spring and fall.

Further, the scientists noted in the study that humans were the top ignition source of the large wildfires studied, with exception for fires in the Mississippi Alluvial Plain. Lightning was another common ignition source.

“It’s not necessarily human ignitions driving the trend of increasing wildfire patterns,” Donovan said. “In other words, we’re not seeing an indication that there are proportionally more human-caused ignitions than there have been in the past. In the Southern Coastal Plain, which includes much of Florida, lightning ignitions played an important role, too, contributing more to the total area burned in the ecoregion despite being a less frequent cause of large wildfire ignition.”

Although the study didn’t address the causes of the increase in eastern wildfires, the authors noted that ignition sources, climate change and changes in vegetation or fuel could all be considered as potential influences that impact the fire occurrences.

The increase in large wildfires in the eastern U.S. shows a need for more education and forest management in these areas, which are highly populated.

“We don’t have the expansive wildfire problem that the western U.S. does yet, so this is also an opportunity to get ahead of the problem and prepare for shifting wildfire patterns before we start seeing the frequent destructive fires that we’re seeing in the West,” Donovan said.

In recent years, worsening wildfires have had significant impacts on the U.S. Wildfire smoke from fires in 2000 to 2020 canceled out other air quality improvements in the U.S. during that timeframe, one study found.