Was the 2014 wildfire season in California affected by climate change?

Happy Camp Complex, 2014
Happy Camp Complex in northern California in 2014. Photo by Kari Greer.

2014 was a busy year in California for wildland firefighters. Battles were fought over 555,044 acres of blackened ground in the state, which was the eighth largest number of acres burned in the last 28 years. So far in 2015, fires have covered 838,465 acres in California, which puts it fifth highest in 28 years.  (Stats from Cal FIRE and the NIFC National Situation Report.)

We have always been dubious of linkages between one weather event and long term climate change. When a senator brings a snowball onto the Senate floor or a governor talks about this summer’s fires to prove their cases that climate change does or does not exist, both may be over stating their “evidence”.

However, I’m not a meteorologist or climate scientist. But some of them who are, took a stab at investigating the possible attribution of extreme weather-related events in 2014 to global climate change. In their report, Explaining Extreme Events of 2014 from a Climate Perspective33 different research groups explored the causes of 29 different events that occurred that year.

The first event in the report is titled, Extreme Fire Season in California: A Glimpse Into the Future. It is debatable if the 2014 fire season in California was “extreme”, since like we wrote earlier, it had the eighth largest number of acres burned in the last 28 years according to data from the land management agencies. The authors, Jin-Ho Yoon, S.-Y. Simon Wang, Robert R. Gillies, Lawrence Hipps, Ben Kravitz, and Philip J. Rasch, reported “thousands more fires than the five-year average” between January 1 and September 20.

We don’t put very much stock in numbers of fires, since a small spot that can be stomped out by a couple of firefighters counts just as much as a 300,000-acre conflagration. Total burned acres is much more meaningful. The area burned data that the scientists studied was derived from satellite observations, which can underestimate wildfire extent due to its limit in the minimum detectable burned area, timing of the satellite overflights, light fuels cooling before being detected, and obscuration by cloud cover.

The report also examined the Keetch-Byram Drought index, and determined that “in terms of the KBDI and the extreme fire risk, 2014 ranks first in the entire state”, but it was not clear what time period they were referring to (it may have been since 1979).

The authors fall short of attributing the “extreme” 2014 fire season in California to global climate change:

Our result, based on the CESM1 outputs, indicates that man-made global warming is likely one of the causes that will exacerbate the areal extent and frequency of extreme fire risk, though the influence of internal climate variability on the 2014 and the future fire season is difficult to ascertain.

2014 climate events
Location and types of events analyzed in the publication. The image is from the study.

LA Times article about climate change and wildfires draws criticism

An article in the Los Angeles Times about climate change and wildfires that we first wrote about on October 20 is drawing criticism. Reporter Paige St. John cherry-picked quotes from several fire or climate experts that were misleading in order to advance the notion that climate change is not affecting fires, nor will it affect them in the near future in a significant way. We pointed out that Ms. St. John’s article would have been more appropriate on the Times’ Opinion page rather than the News section.

Mother Jones took issue with some of the misleading statements in the Times article:

…The Times piece is very strange. It starts by quoting Roger Pielke, the go-to guy for any reporter who wants a skeptical take on climate change. But even Pielke doesn’t actually say climate is unrelated to increased wildfire activity. Next up is a quote from a guy concerned with fire risk who naturally thinks we should focus on making homes safer, but doesn’t comment on climate science one way or the other. Next comes a scientist who has “concluded that global warming has indeed shown itself in California.” Then a Forest Service ecologist who says “California has had an average of 18 additional days per year that are conducive to fire.”

Next comes a UCI team who reported that climate change will increase fires in Southern California by 64 percent over the next few decades. But instead of simply reporting that, the piece acknowledges only that fires will “increase,” and then casts doubt on the result by noting that the UCI model has error bars which indicate that the increase could be between 12 percent and 140 percent. Then a prediction from a “UC Merced expert” who speculated about “a possible decrease of such fires as dry conditions slow vegetation growth.” Finally a National Park Service climate change scientist is quoted as saying “We are living right now with a legacy of unnatural fire suppression of approximately a century.” That’s true enough. Elsewhere, however, that same scientist has also said, “climate has dominated all factors in controlling the extent of wildfire in Western U.S. forests in the 20th century.”

In other words, virtually everyone quoted in this article either (a) says nothing about climate change or (b) says climate change is an important factor in the rise of wildfires in California and the West. And yet, somehow all of this is written in a way that makes it sound as if climate change has nothing to do with wildfires, and it’s topped by a headline that says in no uncertain terms, “Gov. Brown’s link between climate change and wildfires is unsupported, fire experts say.”

Very peculiar.

And from MediaMatters.org:

The Los Angeles Times reported that “scientists who study climate change and fire behavior” dispute California Gov. Jerry Brown’s comments describing a link between the state’s recent wildfires and climate change. However, numerous scientists and major scientific reports have detailed the connection that global warming has to both recent and future wildfires in the Southwest, including the 2014 National Climate Assessment, which stated that climate change has already “increased wildfires” in the Southwest region and could lead to “up to 74% more fires in California.” Moreover, the experts cited by the Times do not contradict Brown’s statements, and the only one who directly criticized Brown was Roger Pielke; it is unclear from the article whether it quoted Roger Pielke Sr. or Roger Pielke Jr., but both father and son have made dubious climate-related claims in the past that were debunked by climate scientists…

(UPDATE October 24, 2015)

Today the LA Times published an article titled, Readers React: Don’t dismiss the link between wildfires and climate change, scientists say, which includes portions of three letters from experts that disagree with the implied premise in the original article.

LA Times refutes California Governor’s assertion that larger fires are caused by climate change

When California Governor Jerry Brown visited the site of the Rocky Fire that burned over 69,000 acres and destroyed 43 homes, he linked this summer’s large fires in his state to climate change, saying, according to the LA Times,

The fires are changing…. The way this fire performed, it’s not the way it usually has been. Going in lots of directions, moving fast, even without hot winds… It’s a new normal. California is burning.

In an article that should have been published on the Opinion page rather than in the News section, LA Times Reporter Paige St. John wrote:

Brown had political reasons for his declaration.

Ms. St. John supported her argument by listing positions the Governor has taken on climate change, implying, therefore, that the Governor’s stance on climate change is “political”. Governor Brown previously encouraged presidential candidates to state their position on climate change, supported legislation to reduce gasoline use in California, and has spoken about climate change negotiations that culminate in Paris in December.

The article also includes information from fire experts who mention other factors that affect fire behavior, such as landscapes altered by a century of fire suppression, timber cutting, and development.

Ms. St. John wrote:

But climate scientists’ computer models show only that global warming will bring consistently hotter weather in future decades. Their predictions that warming will bring more forest fires — mostly in the Rockies and at other higher elevations, while fires may actually decrease in Southern California — also are for future decades.

The NOAA chart below, from an article we published in September, 2014, displays the average temperature in California for January through August of each year, from 1900 to 2014. It shows a clear trend in California of rising temperatures. Not “in future decades”, but for the last 115 years.

California, average temperature, January through August
California, average temperature, January through August

The graphic below from the 2009 Quadrennial Fire Review written for the U.S. Forest Service by the Brookings Institution, documents the “Lengthened fire season due to climate change”.

wildfire season length climate change
The orange bars show estimates of new fire season length by region. Graphic from the Quadrennial Fire Review published in 2008, titled “The Future of Wildland Fire Management” by the Brookings Institution.

Researchers are predicting that beginning 26 years from now the number of weeks in which very large fires could occur will increase by 400 to 600 percent in portions of the northern great plains and the Northwest. Many other areas in the West will see a 50 to 400 percent increase. The portions of California that have vegetation capable of supporting large fires will see increases of 50 to 300 percent or more.

If they are correct, the effects of climate change are not generations away. Firefighters starting out today will be dealing with this on a large scale during their careers.

Future Very Large Fires wildfires
The projected percentage increase in the number of “very large fire weeks”—weeks in which conditions are favorable to the occurrence of very large fires—by mid-century (2041-2070) compared to the recent past (1971-2000). (NOAA)

It is our position that unusual weather for one day, a month, a year, or even a decade does not prove or disprove a long-term climate trend. So when a senator brings a snowball onto the Senate floor or a governor talks about this summer’s fires to prove their cases that climate change does not or does exist, both are over stating their “evidence”. (In the first example, to a ridiculous extent.)

Both gentlemen need to consider much more data, such as the average size of fires over the last few decades or the California temperatures over the last 115 years.

Average size of fires by decade, lower 49 states, 1990 - 2013

And yes, there are factors other than weather that affect the size of fires, including decades of fire suppression in some areas. But not all large fires have burned in areas that have not been visited by fire in 50+ years. A careful analysis can’t discount the effects we are experiencing now — higher temperatures and longer fire seasons.

Researchers attempt to quantify how climate change will affect wildfire seasons

Future Very Large Fires wildfires
The projected percentage increase in the number of “very large fire weeks”—weeks in which conditions are favorable to the occurrence of very large fires—by mid-century (2041-2070) compared to the recent past (1971-2000). (NOAA)

Researchers are predicting that beginning 26 years from now the number of weeks in which very large fires could occur will increase by 400 to 600 percent in portions of the northern great plains and the Northwest. Many other areas in the West will see a 50 to 400 percent increase.

If they are correct, the effects of climate change are not generations away. Firefighters starting out today will be dealing with this on a large scale during their careers.

Warming due to increasing greenhouse gas emissions will likely increase the potential for ‘very large fires’—the top 10 percent of fires, which account for a majority of burned areas in many regions of the United States. Climate change is expected to both intensify fire-friendly weather conditions, as well as lengthen the season during which very large fires tend to spread.

The potential for very large fire events is also expected to increase along the southern coastline and in the forests around the Great Lakes, although the number of events along the northern tier of the country should only increase moderately given the historically low potential for these events.

For this study, researchers considered the average results of 17 climate model simulations to examine how the potential for very large fires is expected to change. Future projections* were based on a higher-emissions scenario called RCP 8.5, which assumes continued increases in carbon dioxide emissions.

Along with the elevated potential for very large fires across the western US in future decades, other climate modeling studies have projected increases in fire danger and temperature, and decreased precipitation and relative humidity during the fire season. The increased potential for these extreme events is also consistent with an observed increase in the number of very large fires in recent decades.

In addition, scientists have detected trends toward overall warming, more frequent heat waves, and diminished soil moisture during the dry season. The combination of these climate conditions and historic fire suppression practices that have led to the build-up of flammable debris have likely led to more frequent large fire events.

At this very moment, more than 56 large wildfires are burning uncontained throughout the West, putting homes, lives, and livelihoods at risk. The smoke created by these fires exacerbates chronic heart and lung diseases while also degrading visibility and altering snowmelt, precipitation patterns, water quality, and soil properties. In addition to public health impacts, projected trends in extreme fire events have important implications for terrestrial carbon emissions and ecosystems.

The authors of the study also note that these findings could place a burden on national and regional resources for fighting fires. Fire suppression costs in the U.S. have more than doubled in recent decades, exceeding $1 billion per year since the year 2000, the National Interagency Fire Center reports. The vast majority of that money is spent on large incidents.

climate change predicted fire seasons

The research was conducted by government employees at taxpayer expense, funded by NOAA, the U.S. Forest Service, and two universities. The authors were: Barbero, R.; Abatzoglou, J.T.; Larkin, N.K.; Kolden, C.A.; and Stocks, B. The title: “Climate change presents increased potential for very large fires in the contiguous United States”. It was published in Australia in the International Journal of Wildland Fire (copies available for $25).

We checked with Frames.gov which posts copies of government-funded research, and were told by Michael Tjoelker, “Unfortunately, due to copyright issues we are not able to distribute full text versions of Journal articles.” However, Renaud Barbero, one of the authors, sent us a copy.

Thanks and a tip of the hat go out to Bill.

Short film, “Unacceptable Risk: Firefighters on the Front Lines of Climate Change”

In February we showed you a trailer for a short film made by The Story Group that premiered later that month, titled Unacceptable Risk: Firefighters on the Front Lines of Climate Change. Now the entire 12-minute film is available — above.

Here is the description of the film on Vimeo:

…The Story Group [based in Boulder, Colorado] recorded the experiences of firefighters who are repeatedly responding to record-breaking wildfires. Human-caused climate changes are transforming Colorado’s fire environment, bringing higher temperatures, drier fuels, and diseases to forests. These climate impacts mix with other human pressures to create a volatile situation for firefighters and communities. If current trends continue, we can expect more frequent, larger, and more devastating wildfires in Colorado and across the country.

It is really an excellent film. A great deal of information is packed into 12 minutes. What makes it special are the interviews with experienced firefighters who all testify to seeing fire behavior in the last decade or so that to their knowledge is unprecedented, at least in the front range of Colorado. The firefighters interviewed are all very well spoken and have something worthwhile to say.

They include Don Whittemore, an Incident Commander and a firefighter for 22 years; Chris O’Brien, Deputy Chief of the Lefthand Fire Protection District; Rod Moraga, Fire Behavior Analyst, firefighter for 28 years; and James Schanel, Battalion Chief, Colorado Springs Fire Department, firefighter for 30 years.

At the end they make a pitch about climate change, emphasizing how important it is to mitigate it NOW. And they are absolutely right. But there is a strong message for firefighters who are being forced to deal with a new normal. Mr. Whittemore said:

On a day to day basis we’re being surprised. And in this business, surprise is what kills people.

The visuals of wildfire are impressive — the videos, photographs, and time-lapse images.

The film can also be seen on Rocky Mountain PBS television. We can’t embed it here, but that version also includes interviews (beginning at 13:00) with Mr. Moraga and filmmaker Daniel Glick.

We received the following from Ted Wood of The Story Group, an Executive Producer and Camera Operator on the film:

The Story Group is funded entirely through grants and donations, and we’re trying to recoup some of our distribution costs by pointing people to our pay-per-download Vimeo site, where people who want to use the film for fire presentations, workshops, etc can pay $9.95 and download it. We’ve had a real interest from Colorado fire managers to use the film in training, and we’d like to offer it to a larger national audience.