The next time somebody says wildfires in the USA are “unprecedented” show them this. Buried fossil soils found to be awash in carbon
“It looks like there was an incredible amount of fire.”
Soils that formed on the Earth’s surface thousands of years ago and that are now deeply buried features of vanished landscapes have been found to be rich in carbon, adding a new dimension to our planet’s carbon cycle.
The finding, reported today (May 25, 2014) in the journal Nature Geoscience, is significant as it suggests that deep soils can contain long-buried stocks of organic carbon which could, through erosion, agriculture, deforestation, mining and other human activities, contribute to global climate change.
“There is a lot of carbon at depths where nobody is measuring,” says Erika Marin-Spiotta, a University of Wisconsin-Madison assistant professor of geography and the lead author of the new study. “It was assumed that there was little carbon in deeper soils. Most studies are done in only the top 30 centimeters. Our study is showing that we are potentially grossly underestimating carbon in soils.”
The soil studied by Marin-Spiotta and her colleagues, known as the Brady soil, formed between 15,000 and 13,500 years ago in what is now Nebraska, Kansas and other parts of the Great Plains. It lies up to six-and-a-half meters below the present-day surface and was buried by a vast accumulation of windborne dust known as loess beginning about 10,000 years ago, when the glaciers that covered much of North America began to retreat.
The region where the Brady soil formed was not glaciated, but underwent radical change as the Northern Hemisphere’s retreating glaciers sparked an abrupt shift in climate, including changes in vegetation and a regime of wildfire that contributed to carbon sequestration as the soil was rapidly buried by accumulating loess.
“Most of the carbon (in the Brady soil) was fire derived or black carbon,” notes Marin-Spiotta, whose team employed an array of new analytical methods, including spectroscopic and isotopic analyses, to parse the soil and its chemistry. “It looks like there was an incredible amount of fire.”
The team led by Marin-Spiotta also found organic matter from ancient plants that, thanks to the thick blanket of loess, had not fully decomposed.
Rapid burial helped isolate the soil from biological processes that would ordinarily break down carbon in the soil.
Such buried soils, according to UW-Madison geography Professor and study co-author Joseph Mason, are not unique to the Great Plains and occur worldwide.
The work suggests that fossil organic carbon in buried soils is widespread and, as humans increasingly disturb landscapes through a variety of activities, a potential contributor to climate change as carbon that had been locked away for thousands of years in arid and semiarid environments is reintroduced to the environment.
The element carbon comes in many forms and cycles through the environment — land, sea and atmosphere — just as water in various forms cycles through the ground, oceans and the air. Scientists have long known about the carbon storage capacity of soils, the potential for carbon sequestration, and that carbon in soil can be released to the atmosphere through microbial decomposition.
The finding is significant as it suggests that deep soils can contain long-buried stocks of organic carbon, which could contribute to global climate change.
The deeply buried soil studied by Marin-Spiotta, Mason and their colleagues, a one-meter-thick ribbon of dark soil far below the modern surface, is a time capsule of a past environment, the researchers explain. It provides a snapshot of an environment undergoing significant change due to a shifting climate. The retreat of the glaciers signaled a warming world, and likely contributed to a changing environment by setting the stage for an increased regime of wildfire.
“The world was getting warmer during the time the Brady soil formed,” says Mason. “Warm-season prairie grasses were increasing and their expansion on the landscape was almost certainly related to rising temperatures.”
The retreat of the glaciers also set in motion an era when loess began to cover large swaths of the ancient landscape. Essentially dust, loess deposits can be thick — more than 50 meters deep in parts of the Midwestern United States and areas of China. It blankets large areas, covering hundreds of square kilometers in meters of sediment.
The study conducted by Marin-Spiotta, Mason, former UW-Madison Nelson Institute graduate student Nina Chaopricha, and their colleagues was supported by the National Science Foundation and the Wisconsin Alumni Research Foundation.
by Terry Devitt University of Wisconsin News Service
How is this news? As a kid, I saw a layer of fine charcoal several feet below the surface in a bluff face on a ranch near San Antonio, Texas. This was 50 years ago. The layer was approximately 2 inches thick.
My cousins and I wondered at the time what sort of forest fire created that layer.
The bluff and the fine carbon layer are still there.
The finding is significant as it suggests that deep soils can contain long-buried stocks of organic carbon, which could contribute to global climate change.
The stumps and logs and bits of charcoal I see lying around from fires a hundred years ago show how little charcoal changes in the Colorado mountains. Poking the soil [shows] more charcoal. What exactly do they think charcoal will do to become CO2? Maybe if we wish really hard and clap all our hands at once, it will grow wings…..
There is a profound scientific blunder in the press release.
We are not properly scientific if we accept statements like this.
The blunder is that the speculation about how the carbon ended up where it is, and the general conditions at the time, are written in the affirmative, yet all of that is speculation.
In this quote below, all statements of “fact” concerning what happened in the past are speculation, not fact, and so cannot be written in the affirmative…
“The soil studied by Marin-Spiotta and her colleagues, known as the Brady soil, formed between 15,000 and 13,500 years ago….It…was buried by a vast accumulation of windborne dust known as loess beginning about 10,000 years ago, when the glaciers that covered much of North America began to retreat.
“The region where the Brady soil formed was not glaciated, but underwent radical change as the Northern Hemisphere’s retreating glaciers sparked an abrupt shift in climate, including changes in vegetation and a regime of wildfire that contributed to carbon sequestration as the soil was rapidly buried by accumulating loess.”
“Science” is taught to schoolchildren like this. Then they grow up to give me grief, and I to give them greater grief, when I attempt to turn them into proper scientists, citing evidence for all claims of fact, and being properly speculative about all conjectures.
When you think in a properly conjectural way, you discipline yourself to be open to new ideas and associations, you form stronger defenses of your speculations, and you develop more rigorous tests of them.
When you accept the orthodoxy of “established science.” you fail.
As an undergrad, I took an anthropology course taught by a grad student. For a good part of the class, he presented the current Homo family tree, and arguments for it – based on speculated dates and bone morphology, and the assumption of evolution by natural selection.
Then, with a family tree all in place leading up to Homo sapiens, he told us that all of this was most likely to be overturned and modified as the years go by.
I have seen this to be true since that course a few decades ago – Nat Geographic kept confirming what this proper scientist knew.
Fires aren’t happening at a greater rate than in the past, but they are being put out at a faster rate. Until the last 60 years or so there wasn’t much that could be done about forest fires, nowadays humans have an affect on these fires, putting them out much faster than in the past. Before humans developed fire fighting technology these fires had to burn until all the fuel was gone or it rained heavily enough to make a difference.
Once again we have a study about something interesting but obscure, the dark layer of “Brady soil,” which then tacks on some sort of Global Warming, CO2 bull, in an attempt to rise from obscurity.
We should refer to these appendages tacked onto papers as “the carbon tacks.”
We should also understand it isn’t easy to be obscure, working on an obscure topic. Whether it is art or science, such work involves loneliness and poverty, and in some cases there is no financial support whatsoever, and the person is working purely out of love for the particular “Brady soil” they study. However, even in the case of such altruistic souls, there is a longing for support and understanding, a deep wish someone would come along and say, “Wow! I think that is worthwhile! Here’s a wad of cash so you can quit your real job and focus on Brady soil.”
In such cases there is a tendency to genuflect towards the rich, even if the rich are fools, hoping for a handout. There are plenty of examples of geniuses like Bach and Mozart dressed in the same livery the butler wore, genuflecting to so-called “lords” of their time, even when such “lords” were men who who played the piano with their fists.
We are seeing the same thing played out now, with scientists putting “the carbon tacks” into their papers as a genuflection towards the so-called “lords” of our time, who happen to be able to print money out of thin air, down in Washington, managing our budget with their fists.
It is up to the real geologists to look at papers such as the above paper, and see if it actually contains any new knowledge about “Brady soil.”
“The finding, reported today (May 25, 2014) in the journal Nature Geoscience, is significant as it suggests that deep soils can contain long-buried stocks of organic carbon which could, through erosion, agriculture, deforestation, mining and other human activities, contribute to global climate change.”
I thought the biggest “carbon” threat was CO2 gas and coal, not minute, solid carbon particles that, if unearthed, remain solid and are not burned. As for layers of charcoal buried many feet under the current surface of the ground, of course wildfires, once started, spread for as long as there was sufficient fuel to feed them. After all, there were no government agencies around to try to put them out or contain them. Just a few years ago, during some deep digging in the Baltimore inner harbor area, a layer of charcoal found many yards deep. It was estimated the fires were raging about 5,000 years ago.
Here’s a neat clip of Mozart meeting the emperor, which is a little like a Climate Skeptic trying to speak truth in Washington DC.
Here’s the clip: http://www.youtube.com/watch?v=Zl-N2JleNeU
isn’t this really what peat moss is also?
Is that what they’re doing? I read just the press release, and decided whoever wrote it had succumbed to the media confusion of ‘carbon’ with ‘carbon dioxide’, and somehow all that black carbon was going to evaporate into the air and heat up the Earth. Was there a more profound misconstruction in the paper itself? I’d rather not have to bother reading it.
/Mr Lynn
Lake bed deposits in Alaska showed warming led to less fire with greener growth. Acreage burned has increased in the Lower 48, while number of fires has decreased:
http://wildfiretoday.com/wp-content/uploads/2010/12/Wildfire-acres-burned-1960-2010-US-AK.jpg
http://wildfiretoday.com/wp-content/uploads/2010/12/Wildfire-average-size-by-decade-united-states-a.jpg
If warming leads generally to fewer fires, we must look for other reasons for ash at 15ky. Here are some possibilities.
1) Humans arrived and didn’t bother to douse their campfires. They may have even used fire to flush game.
2) Humans arrived and killed off grazers, leading to greater growth of grass and brush, hence more fires.
3) Receding ice exposed peat bogs which ignited. Cf. Siberia today: http://www.nasa.gov/mission_pages/fires/main/world/20120828-russia.html
–AGF
All this talk about an organic-rich soil and not a single mention of the total organic carbon (TOC). Is this university science or play time? These paleosols, as a true scientist would call them, can contribute as much to atmospheric carbon dioxide as I can to sea level by pissing in the ocean.
For anyone shaking their heads thinking university scientific research standards couldn’t possibly get any lower than this garbage report, think again. Imagine these and other findings being compiled for debate between today’s top collegiate debate teams. I agree with the poster above who said we’re in the ‘Dark Age’. Figuratively speaking, of course.
Our Top Orators in Action: http://www.youtube.com/watch?v=I9ZFoI2oFnI