Fires which burn 1,000 acres or more are considered “large.” That’s well over a square mile (1.5625 to be precise). Imagine a wildfire consuming an entire square mile — it’s huge, clearly a devastating conflagration.

So when I learned that the “Rocky fire” in California had burned through more than 100 square miles, I knew it was huge beyond huge, the biggest fire I’d ever heard of. It’s the kind of raging inferno that costs so much money, property, even lives at times, that takes so many resources to fight, it’s more than just a drain on resources, it’s a disaster, at least for those who live in the vicinity.

It seems these days that in the western U.S., fires burning more than a square mile are no longer the exception that makes you wonder what’s gone wrong. These days, in the U.S. west they seem to be the norm. And we know what’s gone wrong.

A lightning-sparked fire in the Helena National Forest northeast of Lincoln has grown to 2 square miles since Monday. Its rapid growth led to the evacuation of a dozen nearby cabins, most of which are second homes…

What’s wrong is man-made climate change, sometimes called “global warming.” It has created enough heat in the western U.S. to bring the kind of scorching temperatures that make wildfire grow, and it has made the western drought so much worse, the snowpack so much less, that the forest, the grassland, the brush, the scrub in the desert, are dry as a bone, ready to go up like a matchstick.

Wildfires racing through drought-stricken Southern California have burned over three square miles of land and two cabins. A fire erupted shortly after 1 p.m. Friday in the Angeles National Forest northeast of Los Angeles. Gusty winds quickly drove the flames through 800 acres of brushy ridges near Glendora. Two campgrounds containing at least 40 people have been evacuated….

Over the last few decades there has been quite an increase in acres burned by wildfire in the U.S. And it is not due to factors like land use or fire control practices. Those factors have an effect to be sure, but the science has been studied in detail and the result is clear: the real cause of the tremendous increase in wildfire burn area is man-made climate change: global warming.


The increase is, not to put too fine a point on it, “statistically significant.” This can easily be established with “changepoint analysis,” and with other methods too. The model we get from changepoint analysis (plotted as a blue line) is in excellent agreement with what comes from a smoothing method (lowess smooth as a red line, with error bars as dashed red lines).

And a blaze northeast of Colville scorched almost 5 square miles and forced evacuations at campgrounds in the area.

But that won’t stop deniers denying, in large part because not every year is a horrific wildfire year. They take any year that does’t break the record or even reach to extremes, and hold it up as their version of “proof” that there’s nothing wrong. Think I’m kidding? Just to mention a single denier (he’s hardly the only one), that’s exactly what conservative columnist George Will does regularly. In fact, when it comes to global warming, cherry-picking like that is his stock in trade.

In eastern Oregon, a lightning-caused fire south of Baker City moved west toward Black Mountain and several summer homes. People in that area and those along a creek to the south were ordered to evacuate. The 20-square-mile fire burned an unknown number of structures in a neighborhood Thursday….

Any year at all that isn’t one of the worst on record, is “fuel” for their special brand of misdirection. You may have noticed in the above graph, for instance, that both 2013 and 2014 weren’t among the worst years for U.S. wildfire. Then why aren’t we hearing from them lately about how an increase in wildfire is one of Senator Inhofe’s “hoax” stories?

Because this year is shaping up to be the worst on record.

The weather helped the largest Montana fire, in Glacier National Park, spread from just a few acres Sunday to more than 23 square miles Friday…

In addition to compiling statistics on annual total acres burned, the National Interagency Fire Center also reports total year-to-date figures (although only since 2005). Here’s how year-to-date figures (through August 14th, plotted in red) since 2005 compare to annual totals since 1960 (plotted in black):


Note that this year has the most acres burned by this date. No wonder deniers don’t seem to want to talk about wildfire … except to blame it on something else. Anything, except of course the real root cause: global warming.

Hundreds of people were evacuating from the central Washington city of Chelan as lightning-sparked wildfires advanced. Flames and smoke were visible from downtown.

The fires were among those being battled throughout Washington, including an uncontained blaze near Cougar Creek that had burned 28 square miles near the Yakima Indian Reservation.

In fact there’s a distinct possibility that this year could not only break the record, it could reach a new milestone: over 10 million acres burned. The highest on record is 9.87 million acres in 2006, but that record may fall.

Two fires have charred dry Lower Lake, the most recent burning 38 square miles of thick brush and oak trees in Lake and Napa counties. It is more than halfway contained.

An earlier, larger fire in the same area was finally fully contained Friday more than two weeks after it broke out. The blaze destroyed 43 homes…

If it does, it won’t be the only unpleasant milestone we reach this year. We’re very likely to set a new record for hottest year, as 2015 is on pace to blow out 2014, the current hottest year on record. It’s also poised to rise above pre-industrial temperature by a full degree Celsius, halfway to the 2-deg.C limit which some think is a “safe” upper limit, but really isn’t safe … it’s just a limit which might be very very bad but we still might escape total disaster. And the level of atmospheric CO2, even after allowing for the seasonal cycle, is itself about to cross over 400 ppm.

A fire on the Warm Springs Indian Reservation in rural central Oregon exploded to more than 50 square miles Friday, forcing evacuations of a rural subdivision and a resort that had 400 guests booked Thursday night…

President Obama is proposing the “Clean Power Plan” in an effort to bring CO2 emissions under control, but Republican politicians are frothing at the mouth to criticize it. I say it’s not enough, but at least it’s a start. They say their usual, tired bullshit about “destroy the economy” and “job-killer” and “freedom!” All the while, they deny the reality of global warming, and/or the fact that we’re causing it, and they certainly deny that we should, or even could, do anything about it … while protesting that we should have a “debate” on the issue because they are “not a scientist.” It’s just their excuse to put the corporate profit of their big-money cash donors ahead of the safety and health of us and our children.

But I keep seeing the truth about global warming. Part of that is the truth about wildfire increase in the western U.S. I used to think that a wildfire burning 100 square miles was the biggest I knew of, maybe even the biggest ever. Today I read this news:

A giant blaze on the Idaho-Oregon border grew to 414 square miles Friday, scorching grassland ranchers need to feed cattle and primary habitat for sage grouse, a bird being considered for federal protection…

As for “ruining the economy,” how’s this for you?

The U.S. Forest Service is spending about $100 million a week fighting wildfires and will exhaust its firefighting budget next week, Agriculture Secretary Tom Vilsack said Friday…

21 responses to “Hellfire

  1. In 5 hours the Rocky fire burned what the models expected it to burn in 5 days. None of the fire fighters, including managers with 30 years experence could remembers such extraordinary fire behaviour.

    However, that is just where we have a good view of the fire. Up in Alaska, many fires are just allowed to burn – a good thing in the long run,

  2. lockwooddewitt

    The past day has seen the realization of my worst fears: little to no rain, but lightning and wind-> the east side is on fire. http://www.oregonlive.com/pacific-northwest-news/index.ssf/2015/08/oregon_washington_wildfires_ex.html

  3. For context, 414 square miles is 264,960 acres. That would put the Idaho-Oregon fire at #38 on by area on this list of worst North American fires, give or take:


    That’s more or less the middle of that particular table. (Most of the smaller ones are in there (I infer) because of casualty and/or damage figures. Here’s hoping that doesn’t come to characterize this one.)

    The biggest one on record for North America is the 1950 Chinchaga fire, mostly in British Columbia–also severely affected by this year’s fires:


    Looks like another budget-buster in the works.

    Turning back to the Chinchaga fire, it apparently had some remarkable effects:

    The Chinchaga fire produced large amounts of smoke, creating the “1950 Great Smoke Pall”, observed across eastern North America and Europe. The giant smoke release from the conflagration in late September 1950 was first recorded at Ennadai Lake, in what is now Nunavut, on 24 September.The smoke was on a northeastern path, but hit an atmospheric trough and headed southward towards Ontario and the American eastern seaboard.

    The province of Ontario experienced heavy smoke conditions, with the towns of Sarnia and Guelph experiencing three-hour midday periods of darkness, and the city of Toronto turning on its streetlights and automobile headlights during daytime hours. In Toronto power consumption increased by 200,000 kWh during the smoke event. Animals also felt the effects; cows required milking at different times, and birds were seen bedding down midday. Aircraft were grounded, and an aerial search for a downed United States military plane was delayed by the smoke.

    Most of the smoke in eastern North America was born aloft by climatic conditions to high altitudes. As many observers could not smell it, and the news of the massive Chinchaga fire was sparse, affected people drew other conclusions about its source. Explanations included nuclear armageddon, local fires, supernatural forces, a solar eclipse and alien invasion.

    The heavy haze moved on to the Atlantic seaboard of the United States. New York, Pennsylvania, Ohio, Washington D.C., Virginia and Florida all reported effects from the fire. As in Ontario, lights were turned on during the daytime, and animals showed abnormal behaviour. American meteorologist Harry Wexler followed the smoke plume closely, collecting data from a wide area of the U.S. He noted that the plume split in two during the event, with one southern plume getting caught in a stagnant anticyclonic pattern that extended the hazy period. Wexler observed lower temperatures as result of sunlight absorption by the smoke; he estimated a 4 °C (6 °F) drop in the Washington, D.C. area.

    The northern smoke plume traveled over the Atlantic by way of Newfoundland and Greenland. On 27 September 1950, the plume was observed over Scotland, with reports over England following soon after. France, the Netherlands, Portugal and Denmark also observed the plume. Reports by pilots put the haze over Europe at 12 km (7.5 mi) or more in altitude, higher than observed in North America. In early October, a smoke observation was made on the Aleutian Islands, suggesting that the Chinchaga haze had possibly circled the entire globe.

    Wonder if any of that has been modeled?

    I know that the ‘copper moon’ my wife and I witnessed in South Carolina last month was credited–no, make that ‘attributed’–to Canadian wildfires in news reports we heard. But midday darkness?

    Speaking of the Canadian fire situation, it appears that late June-mid July was very bad, but the last few weeks have been better:

    • Two of the fires on that wiki list (Chelaslie River and Binta Lake) destroyed many plantations and other work I’d had a part in. I remember the windy day the Binta Lake fire had its huge run. It raced over 26 km in a 24 hour period. That was truly frightening.

      We had another ~25,000 ha fire in May/June this year that burned up more area I’d worked in at various times and came within a few km of a long term research site of particular interest to me.

      The fuel types in this part of the province often include stands of mountain pine beetle killed trees. Ten years ago, when that epidemic was at its peak, it was growing due to a succession of mild winter temperatures that allowed high larval survival rates. I knew this, but was not prepared to attribute it to climate change. Previous epidemics began the same way. We typically had extremely cold, larva-killing temperatures in October every few years that knocked down populations, but hadn’t experienced this in a few years. Well, ten years later, and we still haven’t had them. The epidemic is long done here because their food ran out.

  4. The evidence for wildfire being caused by global warming increases further when you consider their incidence globally. Although I’ve seen no global statistics (are there any?) I’ve certainly noticed numerous references to ‘unprecedented’, ‘worst ever recorded’ and similar. For example, South Africa (http://www.dailymail.co.uk/news/article-2978982/Wildfires-rage-South-African-tourist-haven.html); Australia (http://www.bloomberg.com/bw/articles/2015-01-06/australias-wildfires-are-getting-worse-because-of-climate-change); Siberia (http://siberiantimes.com/ecology/casestudy/news/n0350-worlds-deepest-lake-shrouded-in-smoke-swimmers-covered-in-ash/); and of course, Alaska (http://www.usatoday.com/story/news/nation/2015/08/13/climate-change-alaska-wildfires/31203153/). Add it all up and you need to be really dumb to deny the climate is changing.

    • I know that there were, several years ago, attribution studies for the US, Canada, Spain and (I think) Greece.

      The latest word, I think, is this:

      Climate strongly influences global wildfire activity, and recent wildfire surges may signal fire weather-induced pyrogeographic shifts. Here we use three daily global climate data sets and three fire danger indices to develop a simple annual metric of fire weather season length, and map spatio-temporal trends from 1979 to 2013. We show that fire weather seasons have lengthened across 29.6 million km2 (25.3%) of the Earth’s vegetated surface, resulting in an 18.7% increase in global mean fire weather season length. We also show a doubling (108.1% increase) of global burnable area affected by long fire weather seasons (>1.0 σ above the historical mean) and an increased global frequency of long fire weather seasons across 62.4 million km2 (53.4%) during the second half of the study period. If these fire weather changes are coupled with ignition sources and available fuel, they could markedly impact global ecosystems, societies, economies and climate.


      There’s a local news story on that here (note that they make you say who your wireless provider is before you can see the text–or at least, that was my experience):


  5. David B. Benson

    Except that the American southwest has experienced several extremely dry episodes during the Holocene which cannot be blamed on global warming. For example, around 800 CE the Anazasi abandoned Mesa Verde for Canyon de Chelly only to later abandon that for the current pueblos along the Rio Grande.

    Here in the Pacific Northwest something similar happened with clear indications of gigantic forest fires at approximately 400 year intervals in Washington and Oregon, but not on the north end of Vancouver Island in British Columbia.

    So I’m not ready to attribute to unpleasant heat and the smoky skies I’m currently experiencing solely to global warming. But I do wish it wasn’t happening.

  6. Regarding the error bars in the first time series, is there is some overlap with the 1960s? IOW, could a statistician say that wildfire area in the 60s and now are not statistically distinct?

    [Response: No.]

  7. Some terrible fires indeed. Likely to get worse.
    My former home state of Minnesota (and neighboring Wisconsin) had some of the bigger ones (but well before my time):
    The latter (Wisconsin) may have caused between 1500 and 2500 deaths.
    These stories may indicate just how bad things can get under drought conditions.

  8. Pete Dunkelberg

    For new readers, Tamino has mentioned fire data before, for instance:
    Beetle connection doubtful:

    George Will attracted to the subject:

    How to search:

  9. How hot, how dry, how windy and fuel loads — those are the main factors at play. Warming temperatures looks globally widespread, but not uniform.

    How dry – patterns of rainfall and drought – are more regional and periodic. and changes to those appear to be climate change related – but it looks more difficult than with temperatures to establish direct attribution.

    More windy (at times of fire risk?), like rainfall, is probably tricky to establish as a direct consequence of AGW, and I’m not sure there’s evidence of it but it doesn’t need to be more windy, just ‘normally’ windy in the hotter drier conditions climate change has helped induce.

    Fuel loads are the one factor that we can directly influence, although it’s also related to the other factors as well – hotter and windier turns vegetation into more flammable fuel, but it can also inhibit further growth. All are inter-related, but it’s not that complicated that we can’t say with confidence that, when it’s dry, warmer temperatures raise the likely numbers and severity of fires.

  10. If or when everything has burned, the deniers will have a field day saying “there are no wildfires anymore, AGW is hoax. Al Gore is *********** .”

  11. 2003 fires in Victoria were in excess of 4000 Sq M. So significant they earned a name, the campaign fires and ran for 56 days; only for fires in 2006/7 to be of almost the same size and run for 69 days. 2007/8 they called for a while the fire storm, until 2009 – that was only 1500 Sq M in total but stands as Australia’s most lethal disaster.
    We calibrate fire danger against fires in 1939 – Black Friday which were widely considered to be as hot as possible. That’s FDI 100. 1983 matched this and more – I’ve seen numbers like 140. 2009 reached in excess of 300.

    Our Prime Minister’s assessment?

    I’ll back willful blindness against facts in what passes for debate these days.

  12. Tamino, would you please post a link to the data used to construct the first plot in your post? Very much appreciated! Scott Denning, CSU

    [Response: Here: https://www.nifc.gov/fireInfo/fireInfo_stats_totalFires.html]

  13. David B. Benson

    Just now there are 2600 firefighters battling wildfires in Washington state with another 200, soldiers, to be added on Sunday.

  14. michael sweet

    This article from the Los Angeles Times suggests that the current fires in the US are not that unusual. The author argues that high fire rates in Alaska, which the author suggests don’t really matter since so few people live in Alaska, have skewed the data. He links to some data. The data seem to me to show a variety of fire patterns across the country. By cherry picking which area to use you could show anything. Of course that is examining only this year and ignores any long term trends.

    I am sure the deniers will link to this article a lot.

    [Response: Lame.]

  15. One small footnote to the analysis I think I mentioned last time as well:

    ” Prior to 1983, sources of these figures are not known, or cannot be confirmed, and were not derived from the current situation reporting process. As a result the figures above prior to 1983 shouldn’t be compared to later data.”

    It’s possible the changepoint is artifical. Not that that changes anything over the past 3 decades.

  16. Oh…and apparently in 2004 North Carolina apparently banned forest fires and did not report any just like they more recently banned sea level rise.