Wildfire aerosols not handled well in climate modeling

From Los Alamos National Laboratory:

Wildfires may contribute more to global warming than previously predicted

They suggest that fire emissions could contribute a lot more to the observed climate warming than current estimates show.

Haze of smoke emanating from the 2011 Las Conchas, NM fire.

Haze of smoke emanating from the 2011 Las Conchas, NM fire.

Particle analysis shows “tar ball” effect is significant

LOS ALAMOS, N.M., July 9, 2013—Wildfires produce a witch’s brew of carbon-containing particles, as anyone downwind of a forest fire can attest.  A range of fine carbonaceous particles rising high into the air significantly degrade air quality, damaging human and wildlife health, and interacting with sunlight to affect climate.  But measurements taken during the 2011 Las Conchas fire near Los Alamos National Laboratory show that the actual carbon-containing particles emitted by fires are very different than those used in current computer models, providing the potential for inaccuracy in current climate-modeling results.

“We’ve found that substances resembling tar balls dominate, and even the soot is coated by organics that focus sunlight,” said senior laboratory scientist Manvendra Dubey, “Both components can potentially increase climate warming by increased light absorption.”

The Las Conchas fire emissions findings underscore the need to provide a framework to include realistic representation of carbonaceous aerosols in climate model, the researchers say.  They suggest that fire emissions could contribute a lot more to the observed climate warming than current estimates show.

“The fact that we are experiencing more fires and that climate change may increase fire frequency underscores the need to include these specialized particles in the computer models, and our results show how this can be done,” Dubey said.

Aerosol samples revealed “tar balls” in the skies

Conventional wisdom is that the fire-driven particles contain black carbon or soot that absorbs sunlight to warm the climate, and organic carbon or smoke that reflects sunlight to cool the climate. But in a paper just published in Nature Communications the scientists from Los Alamos and Michigan Technological University analyzed the morphology and composition of the specific aerosols emitted by the Las Conchas fire.

Las Conchas, which started June 26, 2011, was the largest fire in NM history at the time, burning 245 square miles. Immediately after Los Alamos National Laboratory reopened to scientists and staff, the team set up an extensive aerosol sampling system to monitor the smoke from the smoldering fire for more than 10 days.

High-tech tools enable analysis of smoke samples

Dubey, along with postdoctoral fellow Allison Aiken and post-bachelor’s student Kyle Gorkowski, coordinated with Michigan Tech professor Claudio Mazzoleni (a former Los Alamos Director’s fellow) and graduate student Swarup China to perform this study.

The team used field-emission scanning electron microscopy and energy dispersive X ray spectroscopy to analyze the aerosol samples and determined that spherical carbonaceous particles called tar balls were 10 times more abundant than soot.

Furthermore, the bare soot particles, which are composite porous fractal structures made of tiny spherical carbon, are modified significantly by the organics emitted by the fire. About 96 percent of the soot from the fire is coated by other organics substances, with 50 percent being totally coated.  Furthermore, the complexity of the soot can be categorized into 4 morphological structures as “embedded,” “partly coated,” “with inclusions” and “bare.”

Mixing and classification of soot particles. Field-emission scanning electron microscope images of four different categories of soot particles: (a) embedded, (b) partly coated, (c) bare and (d) with inclusions. Approximately 50% of the ambient soot particles are embedded, 34% are partly coated and 12% have inclusions. Only 4% of the particles are bare soot (not coated or very thinly coated). Scale bars, 500 nm. Right, spherical tar balls dominate in the emissions.

What was missing from the modeling and why it matters

Why is this important for climate? Dubey noted that, “Most climate assessment models treat fire emissions as a mixture of pure soot and organic carbon aerosols that offset the respective warming and cooling effects of one another on climate. However Las Conchas results show that tar balls exceed soot by a factor of 10 and the soot gets coated by organics in fire emissions, each resulting in more of a warming effect than is currently assumed.”

“Tar balls can absorb sunlight at shorter blue and ultraviolet wavelengths (also called brown carbon due to the color) and can cause substantial warming,” he said. “Furthermore, organic coatings on soot act like lenses that focus sunlight, amplifying the absorption and warming by soot by a factor of 2 or more. This has a huge impact on how they should be treated in computer models.”

This experimental research was funded by the U.S. Department of Energy’s Office of Science.

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37 thoughts on “Wildfire aerosols not handled well in climate modeling

  1. Interesting.

    I suspect fires play a major role in ending glaciations, and in the climate changes over the last millenium and the 20th century. Although in the 20th century the fires were domestic and agricultural.

    the largest fire in NM history at the time, burning 245 square miles.

    A fire that size in Western Australia beyond the southwest corner wouldn’t even make the local news.

  2. Anyone know what the scientists at Los Alamos estimate the increase in temperature over the past 15 years has been? A lot of reports like this refer to climate change but fail to quantify any actual changes.

  3. A bit of a leap to claim that a wildfire would affect climate. It will have an impact on weather but climate?

  4. “Wildfires may contribute more to global warming than previously predicted”

    Is there ANYTHING at all that all these climate science whackos can find that might actually contribute to “global cooling” ?

    Answer; If we get a grant to find something that actually cools the planet then no trouble!
    Cooling phenomena coming right up as soon as that grant appears [ /sarc]

    This whole wild fire is looking very much like just another theory looking for an excuse to exist and another grant generating frightener .

    Fires have been endemic throughout the hundreds of millions of years of past geological history. One has great difficulty imagining the colossal scale of the fire storms across the great grassed steppes of Central Asia after a period of heavy rains and lush growth and then a period of dryness and drought.
    Or across the Great Plains of the North America or the vast semi desert and sub tropical areas of Australia after a run of good wet years.
    Or across the vast forests both temperate and tropical of the planet when past climate changes have led to a drying out of those previously wetter and lusher forest regions.
    Wild fires on an immense scale across entire continents down through the ages have shaped our global climate, our global bio-sphere, our human race, our civilisation and our nations since time immemorial.

    So what has now altered that suddenly it is wild fires that are responsible for increasing something called global warming or climate change.

    As a country person who has fought his share of large grass fires, no forest fires for which I am grateful. when will these ignoramuses who lay claim to the title of scientists ever actually start telling it like it is instead of continually twisting and distorting what should be just good science based on observations and not some over hyped scat laden climate model outputs that turns the whole of their claims into nothing more than just another bunch of ridiculous,hard to believe, hyped up and unsubstantiated claims that if this keeps up we are all going to hell in a red hot warmist basket unless “we do something”..

    Philip Bradley says:
    July 10, 2013 at 12:15 am.

    A couple of statistics to add to Phillip Bradley’s post.
    If the Australian state of Western Australia was a country, it would be the tenth largest country on earth in area.

    New Mexico’s fire covered 245 sq miles ie; 634.5 sq kilometres ;/ 634,500 hectares

    From the Australian Bureau of Statistics.
    [http://www.abs.gov.au/ausstats/abs@.nsf/46d1bc47ac9d0c7bca256c470025ff87/ccb3f2e90ba779d3ca256dea00053977!OpenDocument]

    [quote]The ‘Black Thursday’ fires of 6 February 1851 in Victoria, burnt the largest area (approximately 5 million ha) in European-recorded history and killed more than one million sheep and thousands of cattle as well as taking the lives of 12 people (CFA 2003a; DSE 2003b).
    On ‘Red Tuesday’, 1 February 1898 in Victoria 260,000 ha were burnt, 12 people were killed and 2000 buildings were destroyed (DSE 2003b).

    Between December 1938 to January 1939, 1.5-2.0 million ha were burnt, 71 people were killed and over 1000 homes destroyed in Victoria (DSE 2003b, 2003c). The most devastation occurred on ‘Black Friday’, 13 January 1939, when strong northerly winds intensified fires burning in almost every part of the state. Townships were destroyed and others badly damaged. So much ash and smoke was generated that ash fell as far away as New Zealand (DSE 2003c).
    Five years later in 1944, bushfires in Victoria burnt an estimated one million ha, killed between 15 and 20 people and destroyed more than 500 houses (DSE 2003b).

    The ‘Ash Wednesday’ fires of 16 February 1983 caused severe damage in Victoria and South Australia. In Victoria, 210,000 ha were burnt, 2,080 houses destroyed, more than 27,000 stock lost and 47 people lost their lives (CFA 2003a; DSE 2003b, 2003d). Property-related damage was estimated at over $200m and more than 16,000 fire fighters, 1,000 police and 500 defence personnel fought the fires in Victoria. In South Australia, 208,000 ha were burnt, 383 houses were destroyed, 28 people were killed and property-related damage was estimated to be more than $200m (DSE 2003d).

    Serious bushfires occurred in New South Wales in 1951-52, 1968-69, 1984-85 and 1993-94. In 1968-69 over one million ha were burnt and three people were killed (Linacre & Hobbs 1977; RFS 2003a). In 1984-85, 3.5 million ha were burnt, four lives were lost, 40,000 livestock were killed and $40m damage to property was caused (RFS 2003a). In 1993-94, bushfires burnt 800,000 ha, destroyed 287 residential properties and other premises and killed four people (Year Book Australia 1995 (1301.0)). At the height of the 1993-94 fires, over 20,000 firefighters were deployed (RFS 2003a).[ end of quote]

  5. Don’t forget the fires of the outback which normally pass public notice because few buildings get destroyed and fewer people get killed. Where O where are the modellers adding this data to their little graphs.

  6. How long do the described particles stay in the air? How quickly do they disperse, and what effect does dispersal have on heat content in a particular space? My guess is that wind and weather, especially in a dry state like NM, disperse the particles rapidly, and any rain that comes would catch them and drop them to the ground. If I am right, any effect would be temporary, perhaps more so than that of the fire itself, which once extinguished no longer emits heat (though the blackened ground would absorb heat from sunlight). Does the article mention dispersal or precipitation?

  7. Does that come from the “Cow farts & other bullshit” department?

    Some trees are burning somewhere on a small area and that affects climate globally?
    Oh boy! *shaking head*

  8. Since the invention of the internal combustion engine, world wildfires have been greatly REDUCED.

  9. “The fact that we are experiencing more fires and that climate change may increase fire frequency underscores the need to include these specialized particles in the computer models, and our results show how this can be done,” Dubey said.

    We are not experiencing more fires and the data does not show that climate change may increase frequency.

    It may be that the rest of the research is valid but you have already invalidated it by using 2 false premises.

  10. ROM says:
    July 10, 2013 at 2:29 am

    The largest recorded bushfire in WA burned 28 million hectares,(280,000 square kilometers) in 1972/3. from memory.

    I was caught up in a large bushfire beyond the settled areas in the mid-1990s. Back in Perth, people’s reaction was ‘what bushfire?’..

    Incidentally, an estimated 70,000 emus were killed in that fire.

  11. “… fires are very different than those used in current computer models, providing the potential for inaccuracy in current climate-modeling results.”
    ___________________
    This looks like someone’s attempt to climb down from the CAGW bandwagon.

  12. “Philip Bradley says:

    July 10, 2013 at 5:36 am”

    Puts the BoM’s 112 “thermometers across Australia” (1 per ~68,500kilometers squared) in to perspective.

  13. Soot, tarballs? You’d think somewhere amid the smoke they might find CO2. I find it amazing that ecologists bemoan CO2 as the cause of global warming, but also deliberately set fires to “improve” the environment. Hmm…also, wasn’t one of the big western fires (in the US) such a controlled burn run amok?

  14. “measurements taken during the 2011 Las Conchas fire near Los Alamos National Laboratory show that the actual carbon-containing particles emitted by fires are very different than those used in current computer models, providing the potential for inaccuracy in current climate-modeling results.”

    Replace the bold with “providing another source for the reality of inaccuracy in current climate-modeling results.”, and it becomes the truth.

  15. No mention so far of the ‘Black Saturday’ firestorm in Victoria, Australia in 2009. I don’t have the figures to hand for area burnt, which was large but 173 people died, townships like Marysville and Kinglake were destroyed and lots of rain since then has ensured that there is plenty of flammable undergrowth to repeat the process in the future. All it takes is a lightning strike (or a steaming idiot throwing out a cigarette end or a bottle or using unsuitable spark-forming equipment).

    Australia is a land of fire and flood.

  16. Philip Bradley:

    I remember flying at night over the endless miles of WA and there were several large bushfires raging, as well as lightning playing in clouds in the far distance. It was a spooky sight. There was certainly no mention of these fires on the news channels.

  17. So if fires are now thought to cause warming (climate, not because they are burning :-)), doesn’t that mean the CO2 effect would have to be smaller than previously modelled? And if the models are already running too hot compared to reality…Settled science…except when its not.

  18. So what if it changes the models? The answer will be the same, from multiple lines of evidence.
    /not quite sarc

  19. “providing the potential for inaccuracy in current climate-modeling results.” So they are not already inaccurate?

  20. “We’ve found that substances resembling tar balls dominate, and even the soot is coated by organics that focus sunlight,” said senior laboratory scientist Manvendra Dubey, “Both components can potentially increase climate warming by increased light absorption.”

    Someone should tell Manvendra Dubey-Doo that carbon in the atmosphere cools the surface, it doesn’t warm the surface. See my posts Extremely Black Carbon and Ramanathan and Almost-Black Carbon for details.

    w.

  21. Is anyone else having trouble visualizing how a transparent coating can focus the sunlight and heat the underlying particle by 2x?

    1) if you had a spherical half-shell of glass of uniform thickness, it would not focus sunlight.
    2) if you had a lens that would focus the sunlight, wouldn’t it just gather the same energy across the incident side and focus it into a smaller area -hotter but over a commensurately smaller area.
    3) Given our hemispherical area facing the sun, wouldn’t a fair portion of the incident light reflect away, and the light impinging at right angles bounce back (albedo).
    4) wouldn’t the heating effects be further reduced if the coating was not transparent and colourless?

    Finally an observation arising from the fires. There has been much criticism of dominant climate science for settling on temperature as the measure of warming, ignoring in significant measure enthalpy changes in changes of state, changes in population of living things, changes in wind and wave energy, currents etc. Perhaps it would be instructive, if possible, to calculate all energy, including potential energy (stored in living matter, fossil fuels and the like), sensible heat from the sun… This would be a useful ‘inventory’ of the earth’s many energy forms against which changes in the temporal climate system could be better evaluated. The fire, for example is stored sunshine from a previous time and naturally it adds to the heating of the atmosphere, no matter what the smoke does or doesn’t do. It seems a trivial matter to be considering whether the smoke from a fire like this blocks out the sun. Surely reflection back from the particles comes back down to the ground and convection causing winds and rising hot air which delivers a fair part of the heat to be disposed of at altitude are bigger issues than the puny albedo and heat trapping of smoke.

  22. Oh my. So from observations of one fire they assume
    that “tar balls” predominate. In all fires.

    Hey geniuses! The forests around Los Conchas are all conifers! They
    put out sap that easily burns into tar. The huge Ponderosa pines there
    put out lots of it.

    I’m not impressed. Now if they also had data from a fire in a hardwood
    forest, and it also showed “tar balls”, I might buy this more.

  23. Not quite appropos the tar b*llocks, but on a related subjet, ie the burning of huge swathes of rainforest in recent years:

    Has there been any research at all into any correlation between the cutting down and/or burning of huge wathes of rainforest in South America and Indonesia (for example), and the rise in carbon dioxide levels?

    Surely before this destruction, these enormous forests – which as a shoolchild I was taught to think of as the ‘lungs of the world’ – absorbed vast amounts of CO2 which they converted to oxygen. The wholesale destruction of these forests in the past generation, as well as various largescale wildfires around the world, must substantially change the proportion of the trace gas CO2 being absorbed by vegetation, ditto the O2 .

    I had the following sent in a publicity email today by a food activist site: I’m no scientist but if what they write is anywhere near the truth, maybe here is another way in which the earth’s atmosphere is changing – adding to CO2 levels – which may not be incorporated into the models:

    ” … The rainforests of Indonesia are an ecological treasure: They’re home to critically endangered species like the orangutan and the Sumatran tiger, and they also store more carbon than the entire world emits in 9 years. Now snack and cereal giant Kellogg’s has made a huge deal with a company that’s wiping these forests off the map.
    Kellogg’s has just launched a partnership with Wilmar International, the world’s largest palm oil trader. The palm oil industry has had a devastating impact on the forests of Southeast Asia, wiping out millions of hectares of forest and releasing hundreds of millions of tons of carbon into the atmosphere every year. And even among palm oil companies, Wilmar is especially terrible: Satellite evidence recently proved that it’s been illegally logging on protected forests for decades.
    Wilmar’s record is so bad that Newsweek named it the least sustainable corporation in the world — worse than Exxon Mobil, TransCanada, and even Monsanto…. “

  24. Chris R. says:

    July 10, 2013 at 12:55 pm

    Oh my. So from observations of one fire they assume
    that “tar balls” predominate. In all fires.

    Hey geniuses! The forests around Los Conchas are all conifers! They
    put out sap that easily burns into tar. The huge Ponderosa pines there
    put out lots of it.

    I’m not impressed. Now if they also had data from a fire in a hardwood
    forest, and it also showed “tar balls”, I might buy this more.

    ====
    Another reason to keep reading WUWT: a wide variety of general and specific knowledge.

    Chris R – many thanks!

    Auto

  25. “Wildfire aerosols not handled well in climate modeling”

    Shouldn’t the question be “What does climate modeling handle well?”

  26. Just all the O2 forcibly separated from the (immense!) primordial pool of CO2 by plants trying to rejoin its original partner. Carbon.

  27. They need to factor in Mt. Charleston (Spring Mountain Range) burning just outside of Las Vegas where I live. An equivalent of over 14,000 football fields are already engulfed. It’s still out of control. It was started by a lightning strike (not global warming).

  28. If i may add to the the comments about Australian bushfires -yes that’s what we call them. As a young man in western Queensland on a property 900 square miles we had a number of bushfires in 1955-6. One burnt nearly half the property; the fuel, Spinifex grass, is highly combustible. Early explorers frequently commented on aborigines association with bushfires the use of which is part of their culture. Of course they have only been on our large continent for 40,000 years – burning, burning. Cheers from sunny Sydney.

  29. First of all – the science is settled. That’s why so many papers claim to show something new, unprecedented, etc. that greatly impacts our understanding of climate and has enormous implications. But somehow none of these new things are in the “settled” climate models. (Yes, I know that you can’t put something in a model until it’s discovered.) My point is that it is stupid to say it is settled. And even more stupid to think that you will get accurate “projections” from models that leave out so much.

  30. Gary Pearse says:
    “The fire, for example is stored sunshine from a previous time and naturally it adds to the heating of the atmosphere, no matter what the smoke does or doesn’t do.”
    I like this way of looking at it. If timber is an energy bank, which it seems to be, how significant is it? Unfortunately, some deforestation is happening. While we know the Atmosphere and the Oceans probably dwarf the ability of trees and grasslands to absorb and release energy, we might phrase the question as, Man versus Plants. Who has the bigger effect? And to make tinfoil hat comment, Who says the plants adapting to any change in the climate, aren’t on our side? Are they going to suicide themselves to prove the Alarmists correct?

  31. Yep, glad you caught up with that one Anthony, it’s one of the feedback mechanisms that dd to the climate change process, to deny forests burning don’t affect climate would be preposterous. On their own they wouldn’t do much harm other than to the species living there, but added to the already excessive CO2 levels, twice what they were a century ago, this has to be seen as an extra feed in, and most likely caused by increased temperatures and thus dryness andsusceptibility to fire. Seems like a no-brainer, but plenty of no-brains seem to have difficulty just with the concept of carbon dioxide being anything but a good thing.

    [snip . . for that to be carried here you would need to add references to who is being quoted . . mod]

  32. More on Salby:
    After many years of operation of the first company, the subject created a second, for-profit company that acted as a subcontractor to the first company. The subject was the sole owner and employee of the second company, which existed solely to receive grant funds from the first company and pay them to the subject as salary.

    In relation to the time sheets, a report of the investigation said:

    When we asked him (Dr Salby) to supply supporting documentation for the salary payments, the subject provided timesheets reflecting highly implausible work hours—for example, the subject claimed effort averaging nearly 14 hours a day for 98 continuous days between May and August 2002 (including weekends and holidays), and in other instances claimed to have devoted as much as 21 hours per day to the project.

    So a crook, not a fearless defender of truth, certainly not someone you should be siding with. But then you’re desperate for anything these days as evidence piles in from every corner, and few but the truly challenged believe any of your fossil-fuel funded disinformation. One thing is for sure, when the next generation are looking for scapegoats, for those who delayed action and sentenced them to a chaotic, dangerous future, your name with be high up the list. If you’re still alive then they’ll come for you.

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