Tennessee had 391 wildfires last year
July 12, 2021

Wildfires have ravaged the American West in the recent past. Of the 10 costliest wildfires on record, only two occurred prior to 2017, according to the Insurance Information Institute. And this year is shaping up to be more of the same. When considering total acres burned, 2020 was very close to being the most destructive wildfire year on record; as of the start of summer, 2021 is on pace to exceed last year’s numbers.

The defining wildfire event of 2020—the August Complex Fire—was started by a series of Northern California lightning strikes, and quickly became the largest wildfire event in the state’s history. While California gets much of the attention for wildfires, several other states have been severely impacted as well. Behind California’s 4.1 million acres burned in 2020 were 1.1 million acres in Oregon, almost 1 million acres in Arizona, and 842,000 acres in Washington.

Nationwide, the number of acres burned each year over the past 15 years is up considerably compared to the same timeframe prior to 2005, even though the number of fires has noticeably declined.

While lightning is an obvious cause of wildfires, the National Park Service has attributed nearly 85% of wildfires to human activity, including campfires, debris fires, powerlines, electrical malfunctions, cigarettes, and arson. When assessing the damage done by wildfires, though, lightning-caused fires have historically been more destructive. Data from the National Interagency Fire Center shows that lightning accounted for the great majority of burned acres since 2001, though there have been several years where more land area was burned by human-caused fires, including 2020.

The severity of wildfires is largely affected by climate conditions, and in 2021, several western states remain trapped in a persistent “megadrought.” Large portions of the region—including parts of Utah, Arizona, Nevada, California, New Mexico, Colorado, and Oregon—face “exceptional” levels of drought, which is the U.S. Drought Monitor's most severe category.

Based on recent trends, California has been the state most threatened by wildfires, as 40% of all burned acres last year fell within its borders. California also had the most properties at risk of wildfire damage by a significant margin. Its 2 million at-risk properties was nearly three times as many as the 718,000 in Texas, 371,000 in Colorado, and 238,000 in Arizona, according to the Insurance Information Institute.

However, wildfires affect each state differently. More sparsely populated states like Montana and Idaho, for example, have only the fifth-highest and ninth-highest number of properties at risk for wildfire damage, yet those properties represent between a quarter and a third of all properties in the state, whereas only 15% of properties in California are estimated to be at risk.

To determine the impact that wildfires have had on various states, researchers at Filterbuy compiled data from the National Interagency Fire Center and the U.S. Census Bureau for 2020, then ranked states by the total number of acres burned. Related data included in the analysis were the total number of fires, the burned acreage as a proportion of the state’s total land area, and human-caused fire acreage as a proportion of total fire acreage.

The analysis found that in 2020, 391 different fires burned a total of 4,207 acres of Tennessee land. Here is a summary of the data for Tennessee:

Total acres burned: 4,207
Total number of fires: 391
Burned acreage as a proportion of total land area: 0.02%
Human-caused fire acreage as a proportion of total fire acreage: 99.9%
For reference, here are the statistics for the entire United States:

Total acres burned: 10,122,336
Total number of fires: 58,950
Burned acreage as a proportion of total land area: 4.49%
Human-caused fire acreage as a proportion of total fire acreage: 59.3%

For more information, a detailed methodology, and complete results, you can find the original report on Filterbuy’s website.