The U.S. is on track to shatter the record for the average size of wildfires this year

The number of fires is decreasing, but fires are growing larger

Average wildfire size in the United States 1985-2020
Average wildfire size in the United States, except Alaska, 1985-2020.

While all the wildfire statistics for 2020 are not yet available, the data through December 2, 2020 shows that the United States is on track to shatter the record for the average size of wildfires. Looking at the last 35 years, the average size of fires this year was the highest ever, 168 acres. This number has been growing rapidly year to year (see the chart above). The second highest was 145 acres in 2018, and third highest was 132 in 2017.

From 1985 through 1993 the average size was 27 acres — 16 percent of the average size in 2020, 168 acres.

Total wildfire acres US 1985-2020
Total wildfire acres US except Alaska, 1985-2020
Number of wildfires US 1985-2020
Number of wildfires US except Alaska, 1985-2020

From looking at the data, here are some highlights:

  • During the last 35 years, the number of acres burned this year in the lower 49 states was the 5th highest.
  • The number of fires has been declining. This year was the fourth lowest number in the last 35 years. The first, second and third lowest were 2013, 1989, and 2019 respectively.

Fewer, but larger fires — why?

The number of fires may be declining because we are better at preventing them. NFPA data shows the number of highway vehicle fires has declined from 456,000 in 1980 to 182,000 in 2018. The highway vehicles fires per billion miles driven has decreased over that same period from 299 to 56.  In addition, we may have better spark arrestors on equipment, and, fewer people are smoking and those that do, smoke less.

Higher temperatures most likely has led to lower live and dead fuel moistures, more preheating of vegetation, extreme weather, more rapid fire spread, and increased resistance to control of fires. And when there is more fire on the landscape, the same number of forestry technicians year after year can’t suddenly increase their firefighting output by 300 percent.

Increasing temperature last 200 years

All of the wildfire data in our charts here excludes Alaska. I treat that state separately because:

  • They don’t fully suppress most fires in Alaska, or sometimes just try to herd them away from communities. Fires can grow huge which really skews the numbers for the nation.
  • Alaska’s burned acres can vary widely from year to year. For example, so far this year they have only burned 181,234 acres; the other 49 states burned 8,708,060. In 2015   5,111,404 acres burned in Alaska.

I also do not show on charts the numbers before 1985 because the data available from NIFC shows wide shifts between 1982 and 1984. It appears that a different record-keeping system was introduced at that time.

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Author: Bill Gabbert

After working full time in wildland fire for 33 years, he continues to learn, and strives to be a Student of Fire.

8 thoughts on “The U.S. is on track to shatter the record for the average size of wildfires this year”

  1. There was plenty of data before 1985. But the Biden admin decided to get rid of it.
    Burn acreage in the U.S. is down over 80% compared to a 100 years ago.
    Just because the NIFC deleted a huge part of their graph a couple of months ago, does not mean that it didn’t happen. There are tons of historical evidence e.g. newspaper articles, past wildfire reports, climate reports to show that 50-100 million acres of burn acreage was pretty common not that long ago. Today we barely have 20. And of course they picked the start-date to be 1984 which was the absolute low-point. Its called cherry-picking.

  2. There appears to be little action being taken to address and hold accountable those causing the fires.
    In Oregon and California we know that many wildfires are started by transmission lines, yet the Oregon Department of Energy is attempting to allow Idaho Power to construct a new 300 mile transmission line in rural, environmentally sensitive, hot and windy eastern Oregon. This has left many living in the area terrified due to the fire hazard it will impose upon the people and resources of the area. Over 50 groups and individuals have requested contested cases due to the actions planned by the Oregon Department of Energy. Over 70 different issues have been identified where the actions of the Department fail to meet the requirements of their rules. The issue of fire protection is one of the big issues due to the fact that the Oregon Department of Energy is proposing letting Idaho Power avoid providing fire protection for the areas they wish to cross. This is in spite of the fact that local fire responder, most of whom are volunteers, have indicated that they are not equipped or trained to deal with the fires this transmission line will create. Many of the areas either have no fire protection, have only volunteers who are only trained to fight structural fires and who lack the specialized training and equipment needed to fight the wilderness fires that the transmission line will create. These issues are magnified by the fact that there are areas which are miles from the nearest firefighting resources and where it can take 45 minutes to an hr. to access even after the fire is identified and the firefighters are gathered. For profit utilities need to be held responsible for assuring that there are firefighters and equipment available to respond and fight fires within the timeframes required by NFPA 1710 and the State Fire Marshall. Oregon needs to require utilities to repair, update and increase the voltage their existing lines are carrying to minimize the number of fires they are causing rather than create additional risks by constructing lines in areas of the state that are consistently identified as high fire hazard areas.

  3. I would be really interested in seeing if this trend is consistent across all geographic regions of the U.S., or if there have been one or more regions that have been able to decrease both number of fires and acres burned over the past 35 years.

  4. Tactics have changed over the years. Modified suppression, increase of wilderness and roadless areas, different land management policies as well as climate change have all contributed to larger fires, Acres burned is no longer a valid stand alone yardstick for measuring the severity of a fire season.

  5. I don’t know.

    . . . the same number of forestry technicians year after year can’t suddenly increase their firefighting output by 300 percent.”

    Where’s the study of the relative effectiveness of different strategies and tactics. Most firefighters cling to tradition despite the evidence.

    Where are the studies on the relative effectiveness/ineffectiveness of “fire lines/breaks?” Intellectual discipline?

    I remember standing alone on a fire line when a spot fire started across the line, right under where the rest of the crew was getting a well-deserved rest. They grumbled, but we put a line around it and stopped the spread. Wx_dead calm. In wind, they would be toast and I would be standing helplessly in the black.

  6. We were just talking about this at work the other day. Rather than our usual 30+ .1 lightning starts that we can usually count on in summer, fires get big. Fast. We’ve also seen a lull in activity during certain months only to have everything blow up September through November (when we used to be slow). It’s remarkable how quickly things have changed.

  7. All of the above, plus NOBODY FIGHTS FIRE ANYMORE! Just a lot of burning out. And yes, burning out is fighting fire. I just don’t see a lot of aggressive initial attack, which historically has kept most fires small. Which, I know, is how we got into this problem in the first place. So, what is the answer? More Rx? Managed fires out of season or shoulder seasons? I think a combination of more of everything (including fast, aggressive IA) would be helpful, but it just takes more $ so easier said than done. Going to pay more in the long run, but better to see more proactive work than reactive.

    1. Right on, podnuh! We need to (figuratively) hold the decision-makers feet to the fire and get whatever it takes to get whatever works, especially for more aggressive IA. I went from the USFS to USAF-SAC. I went through two red alerts.

      I don’t know how, for example, the airborne assets like tankers are managed, but there may need to be more of them, and mission-focused equipment and training. For example, I believe that an aircraft designed with enough power to weight ratio to operate in Big Fire Weather and get a perhaps smaller load into tight conditions more quickly needs to be analyzed and tried. The research should follow Rickover’s principle of including minority reports.

      But no matter how you slice it, faster response time is a crucial factor in keeping small fires from becoming big ones. Are there any studies that demonstrate the multiplicity of factors, especially weather/wind, that are most influential?


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