Thursday, May 26, 2016

Another misleading WUWT headline, this one about wildfire

This is about another misleading headline at WUWT (archived here). Anthony Watts wrote about a paper in a special edition of Philosophical Transactions of the Royal Society B about wildfire. His headline was "New study shows no wildfire increases due to global warming, slight decline in recent decades noted". Anthony took it on himself to add the part about global warming. That wasn't in either the press release or the abstract, and I doubt it was in the paper itself, which is paywalled.

You can read about the work in the press release at ScienceDaily.com. Here's an excerpt:
In contrast to what is widely portrayed in the literature and media reports, they found that:
  • global area burned has seen an overall slight decline over past decades, despite some notable regional increases. Currently, around 4% of the global land surface is affected by vegetation fires each year.
  • there is increasing evidence that there is less fire in the global landscape today than centuries ago.
  • direct fatalities from fire and economic losses also show no clear trends over the past three decades.
The researchers conclude:

"The data available to date do not support a general increase in area burned or in fire severity for many regions of the world. Indeed there is increasing evidence that there is overall less fire in the landscape today than there has been centuries ago, although the magnitude of this reduction still needs to be examined in more detail."

So, less fire in recent decades than there was centuries ago.  If you go to the abstract, it shows that the authors were talking about area burned and comparing it to centuries ago:
Instead, global area burned appears to have overall declined over past decades, and there is increasing evidence that there is less fire in the global landscape today than centuries ago.
There was no discussion of causes that I could see, whether from the modern practices of putting out wildfires or because of changes in landscapes or other reason. They did say that there were regional differences and that they had little data on fire severity. The authors also mentioned that "global predictions for increased fire under a warming climate highlight the already urgent need for a more sustainable coexistence with fire".


Western US forest wildfire activity increased abruptly in the mid-1980s


The same edition of the journal had a lot of other articles, including one about wildfires in western USA. In that paper the authors noted an abrupt increase in wildfire activity since the mid-1980s, in apparent contradiction to the paper I just mentioned.
Prior work shows western US forest wildfire activity increased abruptly in the mid-1980s. Large forest wildfires and areas burned in them have continued to increase over recent decades, with most of the increase in lightning-ignited fires. Northern US Rockies forests dominated early increases in wildfire activity, and still contributed 50% of the increase in large fires over the last decade. However, the percentage growth in wildfire activity in Pacific northwestern and southwestern US forests has rapidly increased over the last two decades. Wildfire numbers and burned area are also increasing in non-forest vegetation types. Wildfire activity appears strongly associated with warming and earlier spring snowmelt. Analysis of the drivers of forest wildfire sensitivity to changes in the timing of spring demonstrates that forests at elevations where the historical mean snow-free season ranged between two and four months, with relatively high cumulative warm-season actual evapotranspiration, have been most affected. Increases in large wildfires associated with earlier spring snowmelt scale exponentially with changes in moisture deficit, and moisture deficit changes can explain most of the spatial variability in forest wildfire regime response to the timing of spring.

Fire: a destructive yet essential element


Naturally, WUWT fans don't want to learn about fire, though many have very strong opinions on the subject. There is a much more nuanced article as an introductory piece in the journal, which is open access. Here's some of what the authors, Andrew C. Scott, William G. Chaloner, Claire M. Belcher, and Christopher I. Roos, wrote:
There is an increasing realization that fire is a major Earth system process [4] affecting not only the atmosphere, but also the biosphere in profound ways. Further, it has been recently established [21] that increasing global temperatures will lead to increased fire risk and indeed recent studies suggest that the increase is greater during periods of rapid global change [22]. Fire has not only an impact on the landscape and vegetation, but also on humans [12]. This is a significant paradox. Fire is essential to the health of many plant communities and is used by mankind but is also hazardous to mankind, not only from the fire itself but also from smoke and from post-fire erosion and flooding. It was, therefore, particularly timely to bring together some of the world's leading fire scientists to discuss the impact of fire on the biosphere, including humans, to discuss the role that mankind is playing in altering the nature of fire systems and to examine the central paradox that fire is both a destructive yet essential element of the Earth system and the regulation of that system.

From the WUWT comments


garyh845 complains that the press release didn't say what is causing the world to warm. I thought everyone knew that these days.
May 24, 2016 at 5:42 pm
“The warming climate, which is predicted to result in more severe fire weather in many regions of the globe in this century, will probably contribute . . ”
I note – it does not say ‘the warming climate enhanced by an anthropogenic greenhouse gas footprint . . .’
If they are predicting that future warming is caused by, or increased by, a human footprint then, they should say so.

Gerald Machnee wonders if they are admitting that climate hasn't changed. (No, of course they aren't. It has and is.)
May 24, 2016 at 8:10 pm
Well, they did not fins any increase but threw in their lick about forecast increase with climate change. You mean they are admitting that climate has not changed?? 

Bruce Cobb thinks he's seen a contradiction.
May 25, 2016 at 5:50 am
there is increasing evidence that there is overall less fire in the landscape today than there has been centuries ago

The warming climate, which is predicted to result in more severe fire weather in many regions of the globe in this century, will probably contribute further to both perceived and actual risks to lives, health and infrastructure.

These two statements don’t jibe with one another. We know that it is warmer now, and yet there is overall LESS FIRE, not more. But, in the twisted logic of Climatism, it will result in more fire in the future. Notice, too, that “the warming climate” is simply assumed. We can’t say what the climate is doing now, and most certainly can’t predict what it will do in the future. Cooling may very well be in the cards, possibly decades-long. 
Thing is that the researchers were looking at area burnt, not the number of fires or the severity. Fire weather is bad enough now, and will get worse.

10 comments:

  1. Contrary to the WUWT headline, the actual paper mentions climate change often, in connection with both recent observed trends and future projections. For example:

    "Strong trends in Southwestern wildfire that do not appear to be associated with changes in the regional timing of spring index may lend support to the observations and argument that human-induced changes in forest composition, density and structure are particularly important to changes in wildfire in Southwestern forests [30]. At the same time, the start of the Southwestern fire season—as indicated by the date of first large-fire discovery—has shifted more than 50 days earlier since the 1970s, accounting for about one-third of the increase in the length of the fire season there (table 3). The substantially earlier SW fire season start is consistent with warmer temperatures and earlier spring seasons leading to earlier flammability of fuels in SW forests."

    and

    "Given projections for further drying within the region due to human-induced warming, this study underlines the potential for further increases in wildfire activity [7,13,13]."

    ReplyDelete
  2. Climate Central has several referenced posts and reports that strongly suggest otherwise for western North America:
    http://www.climatecentral.org/news/alaska-entering-new-era-for-wildfires-19146
    http://www.climatecentral.org/news/climate-context-fort-mcmurray-wildfire-20311
    http://www.climatecentral.org/news/large-wildfires-more-common-destructive-19387
    https://www.climatecentral.org/wgts/wildfires/Wildfires2012.pdf

    ReplyDelete
  3. hopefully they will sort it out in july

    https://theconversation.com/fires-are-increasing-in-warming-world-but-a-new-model-could-help-us-predict-them-54466

    ReplyDelete
  4. This is timely for me, and I'll have to keep an eye on it. I'm moving to the mountains of Colorado in a few years.

    ReplyDelete
  5. Less wildfire than centuries ago?
    Is that a surprise?
    There is less forest to burn. Would that not be the major element in the equation, even accounting for the massive increase in human numbers and thus the interactions with forest?
    While wildfire likely increased with the arrival of Europeans into the Americas and Australia, it then would decline with the suppression of indigenous people's burning practices, the large decrease in forest and woodland area, and the advent and spread of 'forest management'.

    But I'm just musing...what is the definition of 'wildfire' used in this one study and how consistent is it in the papers in this special edition? How many tens of thousands of 'controlled burns' are set globally annually?

    ReplyDelete
    Replies
    1. Yes, that and the fact that centuries ago fire services were not, shall we say, quite as advanced (or as prolific).

      Delete
    2. I'd been wondering about the continuation at Fort McMurracy and Earth Observatory provided an answer today:
      http://earthobservatory.nasa.gov/NaturalHazards/view.php?id=88090&src=nha

      Picture = 1000 words

      Delete
    3. Fort McMurray is still under mandatory evacuation; they're hoping to let people in starting June 1, but really only have the town back in action starting June 15 or so.

      The fire flared up again last week, after a couple of weeks of slow burn; they expect it to be episodic like that all summer long.

      Delete
    4. @Nick: this is apparently not an appropriate context for "land-use change" in WUWTer World.

      Delete
  6. I rode through the smoke from a wildfire in the Arizona (Southwest United States) mountains this morning. The road I took used to border miles-long lakes. Today, those lakes were meadows covered by wind-whipped smoke. The wildfire is early for the year and, sure that's weather, but how many years of drought did it take to turn those lakes into meadows?

    ReplyDelete

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