Like Clockwork ...

Wildfires Return … but With or Without Climate Change Component?

Increasing wildfires across the country raise questions of how the media can best make connections to climate change and do so in ways consistent with the best scientific understanding.

Like clockwork, the fire season has hit the western U.S., and hit it hard: large blazes out of control in Arizona, Colorado, and Southern California. In the Gila National Forest, in southwestern New Mexico, the largest single fire, the Whitewater Baldy fire, has scorched more than 152,000 acres, or 237 square miles. Arizona, Florida, Colorado, and northern Michigan all have been caught up in the early wildfire season.

Together, the fires have incinerated more than 208,000 acres, about 325 square miles of forest and brush. So far, none of these fires have threatened a significant number of homes. But how long that will remain the case … anyone’s guess.

A wildfire, when it enters a residential area, is an intensely dramatic event. In the years between 2007 and 2009, four major wildfires, one the second largest in recorded state history, erupted in the Southern California county of Santa Barbara. I covered them for the local weekly newspaper and witnessed sheets of flame racing down chaparral-laden hills and engulfing palatial Mediterranean-style homes.

The 2009 Jesusito fire in Santa Barbara, Calif. Credit: Sacramento Bee.

And then later the smoldering and blackened frames of those homes. Hanging in a closet still standing amid rubble … a ghostly white wedding dress covered in ash. Curiously, the fires were most dramatic as viewed from the city, where they could be seen in full, patches of red glowing everywhere throughout the foothills, and here and there geysers of flame shooting up hundreds of feet into the air, like water spouts.

Those fires were part of a record-breaking stretch between 2007 and 2009, during which time nearly 800,000 acres burned throughout the state, prompting the inevitable comparisons to the similar acreage of Rhode Island.

Forecast for California:  Above-Normal Fire Risk

This year California had an exceptionally dry winter, and above-normal fire potential is forecasted for most of the state through fall.

How can the news media best address the role of climate change in the eruption and spread of wildfires, which in and of themselves have long been an elemental part of the landscape of much of the West, but which in recent years have been growing more frequent and more severe, and have been covering more ground?

Does this increase exemplify future trends, or must a more direct correlation between climate change and wildfire now be made, as the country’s most prominent climate scientist, James Hansen of NASA, tells The Yale Forum?

Climate models consistently indicate that as global warming intensifies big, bad wildfires are going to break out more and more often throughout the western U.S. A study produced by Harvard scientists projects that acreage burned by wildfires in the West could increase by 50 percent by mid-century; in the Pacific Northwest, which is not accustomed to frequent wildfire, the figures rise by between 75 and 175 percent. Researchers doing a study conducted in Montana report that the state could see burned acreage increase by 300 percent by mid-century. “Eighty to ninety percent of the lower 48 show significantly increasing fire risk [as climate change intensifies],” says Ron Nielson, a bioclimatologist with the U.S. Forest Service.

Last summer Texas endured 27,976 separate wildfires, together burning just less than 4 million acres and shattering the previous record. The fires were fueled by extreme heat and ongoing drought and desertification in the state; at the time, Governor Rick Perry famously asked Texas residents to pray for rain.

During the fires, a reporter contacted Nielson and asked him what role — if any — climate change was playing in their spread. Nielson replied in a way many climatologists do when asked about a specific storm event: While no fire could be traced directly to climate change, what was happening in Texas was consistent with trends climate change is expected to produce.

A Deviation Too Extreme to be Natural?

That was in late summer. In November, James Hansen, along with two colleagues at NASA’s Goddard Institute for Space Studies, GISS, posted online a draft version of a paper called “Perceptions of Climate Change: The New Climate Dice.” In it, they demonstrated that many extreme weather events now fall within what Hansen called a “three-sigma anomaly” — a mathematical deviation from natural variability so extreme that it can be directly attributed to anthropogenic global warming.

“What we have shown in our current paper is that the increased frequency and extremity of hot events due to global warming is so great that you can state that it is very unlikely that a given extreme event would have occurred in the absence of global warming,” Hansen said in a phone interview. At this point, Hansen went on, it is no longer necessary to hedge about the role of climate change in the spread of wildfires: “The evidence is clear — we can say that global warming is a major factor in the increase of fires and their increased intensity.” Other factors contribute, Hansen said, the most obvious being population growth, but “climate has become the larger factor.”

The 2011 wildfire in Texas. Credit: Summit County Voice.

In the last year or so, media outlets have more frequently linked extreme weather events to the warming climate. After the National Oceanic and Atmospheric Administration announced that this past March was the warmest on record in the U.S., many national outlets did stories on the relationship between anthropogenic global warming and climate extremes. Traditionally, scientists contacted by reporters seeking to understand record-breaking natural disasters and weather events have offered variations of what Nielson told the reporter asking about climate change and the Texas wildfires: they cannot be directly attributed to climate change, but they may be consistent with trends a warming climate is expected to produce.

The growing tendency among media to directly link climate change with extreme weather is, in itself, controversial; a story published last summer in Newsweek, for example, declared, “Freak storms are the new normal,” inciting criticism from some journalists and scientists, as noted at this site.

Concerns about such coverage commonly touch on a few key points. The first is that even very extreme weather events can fall within the range of natural climate variability, a point made, for instance, in a forum Yale E360 conducted in 2011 on the subject of extreme weather and global warming.

A second common concern deals with messaging: Because climate change is such a politically charged topic, journalists and scientists must be exceedingly careful about what they say about it; the burden of proof is extremely high.

“Scientists know that they will get jumped on as soon as they make an attribution — especially one related to global warming, where there is a huge crew of contrarians standing by ready to jump on them,” Hansen said.

Still, Hansen argues, the evidence is unequivocal: “The climate change includes a shifting of climate zones, poleward movement of tropics and subtropics, that makes the western and southern U.S. more susceptible to periods of extreme heat and drying, the conditions needed to increase fire frequency and the extremity of the fires.”

Hansen is by no means alone among climate scientists in asserting that very extreme weather events now being experienced fall outside of the range of probable natural variability. A major study conducted by German researchers, and published in Nature in March, was called “A Decade of Weather Extremes.” “It is very likely that several of the unprecedented extremes of the past decade would not have occurred without anthropogenic global warming,” the authors wrote.

In addition, a study released by NOAA about increasingly frequent drought in the Mediterranean found that “The magnitude and frequency of the drying that has occurred is too great to be explained by natural variability alone.”

And just this past March, meteorologist Jeff Masters of Weather Underground published a statistical analysis in which he concluded that “It is highly unlikely the warmth of the current ‘Summer in March’ heat wave could have occurred unless the climate was warming.”

Since 2000, wildfires across the U.S. have burned double the average acreage of the previous four decades. Some portion of this increase can be attributed to population growth and expanding suburbs. However, the authors of a 2006 Science study found that these factors had “relatively little effect” in the growth of wildfires in western states in the past 25 years. Instead, they wrote, the shift has been the result primarily of longer, hotter, drier summers. “The transition has been marked by a shift toward unusually warm springs, longer summer dry seasons, drier vegetation, and longer fire seasons.”

Wildfire Impacts … Real-World Local Consequences

Surveys indicate that most Americans are unaware of how severe and immediate climate scientists believe the threat posed by climate change is; nor are they aware of the level of consensus among climate scientists that anthropogenic global warming is occurring. Research demonstrates that people have difficulty caring strongly about climate change in part because it’s hard to see in daily life. As long as it’s framed with utmost journalistic and scientific care and responsibility, wildfire can provide intensely arresting visual evidence of a phenomenon many people might otherwise find distant and abstract.

More to the point, however, the relationship between wildfire and climate change has real-world consequences for millions of people in fire-prone states, beginning with where they live or would like to live and extending to, among other things, whether they’ll be able to afford homeowner’s insurance as climate change intensifies. For instance, Matthew Kahn, an economist at UCLA who has written extensively about the economics of climate change, says that if climate change continues to progress at its current pace, resulting in more, and more severe, wildfires, insurance policies in fire-prone areas could become significantly more expensive.

Climate change is making it into press coverage of wildfire more frequently than it used to. During the 2009 Jesusita Fire, which burned 80 homes in Santa Barbara, forced the evacuation of 30,000 people, and attracted considerable national media attention, only the San Francisco Chronicle, among the dailies, dedicated significant space to the subject. But some coverage of the Texas fires included climate change, such as these stories from The Washington Post, The New York Times, and the Houston Chronicle. And in January, PBS began an excellent series called “Coping with Climate Change,” in which, among other things, a scientist is quoted saying record-setting Texas drought has been “enhanced” by human-caused climate change.

More often than not, however, climate change still fails to make it into news stories about wildfire, a paucity of coverage that is particularly notable at local and regional newspapers, which generally offer the most extensive coverage of wildfires taking place in their area and on which residents depend on for detailed reporting of news in their areas. Whether reporters choose to quote studies and scientists who say that climate change is driving wildfire, or whether they simply mention that climate change will exacerbate the conditions that give rise to it, it’s important that climate change make it into their coverage, said Ron Nielson, the U.S. Forest Service bioclimatologist.

“It’s certainly true that current wildfires exemplify future trends, in which big fires are going to happen more often,” said Nielson,  ”But you know, I’ve tended to equivocate in the past, but I actually agree with [Hansen] on this.”

AUTHOR
Sam Kornell is a writer living in California. He can be reached at Sam_Kornell@yahoo.com.

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3 Responses to Wildfires Return … but With or Without Climate Change Component?

  1. Jim Bouldin says:

    This issue is an excellent example of where, and why, we need to be wide and inclusive in our thinking about the effects of climate change, and I ‘d like to use it to throw a reminder in here.

    Wild-land fire is a biophysical process determined almost entirely by fuel structures, ignition sources and weather conditions. No one of them alone will explain large scale fire phenomena and dynamics very well. There is no question that increased drying, resulting from climatic change, will increase the chances that vegetation will burn, because fuel moisture content is one of the big drivers of fire spread. However, many of the global areas prone to fire–Mediterranean ecosystems, range- and shrub-lands, boreal forests etc.–have experienced large changes in other fire drivers, particularly, large increases in the amount and vertical and horizontal continuity of fuels (particularly dead fuels), and a concomitant decrease in landscape scale ignition sources, both occurring over the last one to two centuries. This is very well documented by evidence that includes especially, repeat photography studies, long term vegetation plot monitoring, and soil charcoal analyses.

    These facts are an excellent illustration of one of the sometimes over-looked problems with climate change: that it is overlaid on top of other recent changes that have occurred and which together define a state that is unstable and unpredictable, given past experience and current understanding.

    As far as local reporting on fires, I think it’s unreasonable to expect any discussion about the role of climate change in such stories; local fire reporting is not about that, it’s about the event itself, who’s doing what to fight the fires, where to find shelter, and other crisis related issues.

    • Paul in Sweden says:

      “global areas prone to fire–Mediterranean ecosystems, range- and shrub-lands, boreal forests etc.–have experienced large changes in other fire drivers, particularly, large increases in the amount and vertical and horizontal continuity of fuels (particularly dead fuels), and a concomitant decrease in landscape scale ignition sources, both occurring over the last one to two centuries. This is very well documented by evidence that includes especially, repeat photography studies, long term vegetation plot monitoring, and soil charcoal analyses.”

      The profundity of your statement Jim is almost dismissed in its entirety when you slip in the ubiquitous ‘climate change’ weasel words. We all know climate changes. If you mean Catastrophic Anthropogenic Global Warming say so. This way there will be no ambiguity.

      Don’t use weasel words developed by lobbyists and marketers.

      • Tony Duncan says:

        Paul,

        It is quite clear in the post that he is referring to climate change caused by CO2 added by humans in the last century or so. If you are aware of some of some other cause of the current global avg temperature increase that has been vetted by peer review and explains the various factors that have been extensively studied over the last 40 years, please do so.
        ACC is neither a marketing nor lobbying phenomenon, it is an actual robust scientific theory, so the word “weasel” to me is more appropriate to those that dismiss the science and insist on using discredited arguments solely for the purpose of attacking the science.