New ground truth: soil microbe negative feedback

This could be a game changer. From the University of California, Irvine press release, a finding that suggests soil microbes have a negative feedback with temperature increase. This has broad implications for the amount of CO2 emitted estimated in climate models. It had been assumed that as temperature increased, microbes and fungii would increase their CO2 output. Globally, this microbiotic contribution is large.  The amount of CO2 released from soils worldwide each year is estimated to be about 8-10 times greater than the amount released by humans.

Humans 7, soils 60 - Source: University of Heidelberg

This study shows that soil microbes won’t go into a an “overdrive” mode when soil temperature increases.

Soil microbes produce less atmospheric CO2 than expected with climate warming

Key players in the carbon cycle, they multiply slowly when overheated

— Irvine, Calif., April 26, 2010 —

The physiology of microbes living underground could determine the amount of carbon dioxide emitted from soil on a warmer Earth, according to a study published online this week in Nature Geoscience.

Researchers at UC Irvine, Colorado State University and the Yale School of Forestry & Environmental Studies found that as global temperatures increase, microbes in soil become less efficient over time at converting carbon in soil into carbon dioxide, a key contributor to climate warming.

Microbes, in the form of bacteria and fungi, use carbon for energy to breathe, or respire, and to grow in size and in number. A model developed by the researchers shows microbes exhaling carbon dioxide furiously for a short period of time in a warmer environment, leaving less carbon to grow on. As warmer temperatures are maintained, the less efficient use of carbon by the microbes causes them to decrease in number, eventually resulting in less carbon dioxide being emitted into the atmosphere.

“Microbes aren’t the destructive agents of global warming that scientists had previously believed,” said Steven Allison, assistant professor of ecology & evolutionary biology at UCI and lead author on the study. “Microbes function like humans: They take in carbon-based fuel and breathe out carbon dioxide. They are the engines that drive carbon cycling in soil. In a balanced environment, plants store carbon in the soil and microbes use that carbon to grow. The microbes then produce enzymes that convert soil carbon into atmospheric carbon dioxide.”

The study, “Soil-Carbon Response to Warming Dependent on Microbial Physiology,” contradicts the results of older models that assume microbes will continue to spew ever-increasing amounts of carbon dioxide into the atmosphere as the climate continues to warm. The new simulations suggest that if microbial efficiency declines in a warmer world, carbon dioxide emissions will fall back to pre-warming levels, a pattern seen in field experiments. But if microbes manage to adapt to the warmth – for instance, through increased enzyme activity – emissions could intensify.

“When we developed a model based on the actual biology of soil microbes, we found that soil carbon may not be lost to the atmosphere as the climate warms,” said Matthew Wallenstein of the Natural Resource Ecology Laboratory at Colorado State University. “Conventional ecosystem models that didn’t include enzymes did not make the same predictions.”

Mark Bradford, assistant professor of terrestrial ecosystem ecology at Yale, said there is intense debate in the scientific community over whether the loss of soil carbon will contribute to global warming. “The challenge we have in predicting this is that the microbial processes causing this loss are poorly understood,” he said. “More research in this area will help reduce uncertainties in climate prediction.”

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INGSOC

Why is it that something well known among many other disciplines of science can be such a startling revelation to climate science?

Enneagram

Organic life on earth is closely linked to carbon cycle simply because WE are made out from CARBON and WATER. Every individual absorbs and emits energy according to its inner structure. As every wave train emits and absorbs discrete amounts of energy, so we. Each “feed”of food which is resonant with its frequency and excrete, emit, accordingly. If more complex, as human beings, feed of several wavelengths: as light, sound, water, etc.
Needless to say warmists prefer longer wavelengths ☺ improper for us.

Pamela Gray

So now we have a model of the model?

Pearland Aggie

I’m sure they will find something wrong with *this* model while having nothing to say about GCMs.

AdderW

Another model predicting something that is poorly understood

DocWat

Geeze Geeze Geeze, the hits keep coming. When are these real scientists going to stop picking on those poor AGW guys???

Jimbo

Couple this with
“Amplification of Global Warming by Carbon-Cycle Feedback Significantly Less Than Thought, Study Suggests”
http://www.sciencedaily.com/releases/2010/01/100127134721.htm
A greening biosphere
http://svs.gsfc.nasa.gov/vis/a000000/a003400/a003451/index.html
Co2 is lumpy, contrary to the IPCC assumption of it being a well mixed gas
http://www.jpl.nasa.gov/news/news.cfm?release=2009-196
and what we have is computer model failures.

beng

The new format doesn’t show well on my Firefox browser.Much slower loading too.
Sometimes messing w/a good thing isn’t a good thing.

REPLY:
Which version of Firefox on what OS?

CO2 emissions have increased much faster than atmospheric CO2. The deficiency in atmospheric CO2 probably indicates that CO2 is removed from the atmosphere much faster than our CAGW friends want policymakers to believe.

We found something potentially interesting! Give us more money for further studies!

Paul

“More research in this area will help reduce uncertainties in climate prediction.”
Not that I think that more research is a bad thing, generally speaking, but I can’t remember the last study that didn’t end with what is essentially a request or justification for further funding. And I can’t help but note that the government provides much if not most climate-related funding, and that politicians are generally far less interested in research than I am, except when it provides them something that they can use for their own agendas.
To my mind, the most revealing hockey-stick graph would be the funding directed towards ‘climate science’ since the weather ceased being the weather and became man-made and catastrophic to boot.

Mark Bradford, assistant professor of terrestrial ecosystem ecology at Yale, said there is intense debate in the scientific community over whether the loss of soil carbon will contribute to global warming….“More research in this area will help reduce uncertainties in climate prediction.”
Translation: “We’re not sure, but a *decrease* in atmospheric CO2 could also lead to global warming. Throw more money at us so we can continue to not be sure about it.”

Pamela Gray

I don’t think this will be a game changer at all. We are talking about such a small change in an already extremely small percent of atmospheric gases that this will never be observed as a measurable event. It will always and only exist in models. An educated guess with no statistical difference to be had. And mother nature cares not one red cent for models. That is the real game changer.
My opinion, this is not anywhere near a study you can hang your hat on. And it appears that the researchers are grasping for straws, though they may not have intended it to look that way.
It does however, point out the amusing belief by AGW enthusiasts the notion that microbe emissions under warmer temperatures would be worse than we thought! It is a rather silly study used to refute a rather silly notion.

Jim

On a somewhat related topic, have any of you actual scientists or others who have access to the literature seen any articles on CO2 released by tree roots growing in limestone? I live in a region where the ground is composed of limestone. Roots from trees and probably other plants grow right through the limestone. I assume the roots secrete some sort of organic acid that decomposes the limestone, allowing them to grow through it. I am wondering how much CO2 this process releases compared to how much is sequestered by the plant material. Also, this would represent a case of a plant feeding itself CO2 wouldn’t it? Limestone is a concentrated source of CO2 so I wouldn’t be surprised if there was a net release of CO2 in this case.

RockyRoad

The results aren’t surprising–had the opposite as hypothesized by the warmers been earth’s fate, the earth would have tipped a long time ago to a steamy hot planet with most if not all of the ocean’s water diffused throughout the atmosphere. That this isn’t the case shouldn’t surprise anybody.
The warmers apparently proceed on the belief that our current climate is as warm as the earth has ever gotten. They should study more “geo” and less “theo”.

Baa Humbug

A little knowledge is a dangerous thing. (Don’t know who said it)
“The greatest obstacle to discovery is not ignorance — it is the illusion of knowledge!”
(Daniel J. Boorstin, winner of the 1974 Pulitzer Prize)

The write-up confuses me: Is less CO2 produced because (i) warmer microbes exhale CO2 “furiously” for a short period of time, “leaving less carbon to grow on”, or (ii) warmer microbes make “less efficient use of carbon.” The two possibilities seem mutually exclusive, unless the microbes somehow know how much carbon they have left to be furious about.
The first explanation is the only one consistent with our observation of tropical soils, i.e. they are depleted in organics by active microbes, which remain ready to oxidize any new carbon that becomes available.
Fortuitously, the authors allow themselves an out for the purpose of CAGW fear-mongering: The microbes might adapt (in a way they haven’t for billions of years), so CO2 “emissions could intensify.”

Brad

Pamela-
I respectfully disagree. Enzymes are very temperature sensitive, that is the reason you are a homeotherm, and to think that soil microbes wil simply increase their carbon poutput because the temperature rises is absurd. On the other hand, if their are more soils where microbes are more active for longer periods of the year, the output may increase. Of course, if the temp rise goes beyond the optimum for the enzymes to function to respire, then the amount of carbon will decrease. To think this study is “grasping at straws” is absurd, to me at least.

Brad

I would add that the greatest discoveries in science are often made at the interface between two disciplines, where we know enough to come to real conclusions if only the scientists on both sides could see through the ivory wall of publishing in and reading different journals.

Is the current estimate of the natural carbon flux actually measured?
Or is it based on a model?
When I use Knorr’s 0.55 decay rate for atmospheric CO2, I come up with a residence time (RT) of ~15 years (with 95% cycled out of the atmosphere within 5 years).
When I use the CDIAC anthropogenic emissions history back to 1751 and the 0.55 decay rate, I back calculate a natural CO2 flux to the atmosphere of 437 GtC in 1751, gradually rising to 592 GtC in 2006. The highest value I can find for a pre-industrial natural flux to the atmosphere is 244 GtC from the TOTEM model.
Is the natural carbon flux measured? Is it model-derived? Is it just assumed? Could the natural carbon flux be more than twice the initial conditions assumed in the TOTEM model?

Steve Keohane

Another in a long list of erroneous assumptions. At what point do we know enough about a field of study to actually be doing science with respect to that field. ‘Climate Science’ seems to be at the point of blind men trying to determine if they are examining the same elephant, not yet at the point of defining what that elephant is.
stevengoddard says: April 28, 2010 at 5:50 am
CO2 emissions have increased much faster than atmospheric CO2. The deficiency in atmospheric CO2 probably indicates that CO2 is removed from the atmosphere much faster than our CAGW friends want policymakers to believe.

After many years of rock hunting in Colorado, one can’t help but notice the calcium carbonate coating that occurs on rocks here. I wonder how much carbon is sequestered by that method. It is not as obvious as some of the monolithic deposits, but is everywhere and must be a substantial amount.

Loco

New format is performing just fine Down Under (Mandurah, Western Australia) running Firefox 3.6.3

DonK31

Is this why there is an increase in CO2 500 to 800 years after warming and a decrease 500 to 800 years after cooling? Warming causes an increase in microbial activity, therefore causing more atmospheric CO2. And vice versa?

Spector

I think it would be highly ironic if our minor 1000-year climate cycles were eventually found to be biota-related and analogous to the classic predator-prey cycles. That is where increasing prey animals allow the predator population to rise until they begin to devour the prey faster than this food source can reproduce. Then the numbers of both populations crash until there are so few predators left that the prey population can start rising again.

renminbi

First used by Alexander Pope (1688 – 1744) in An Essay on Criticism, 1709:
“A little learning is a dangerous thing; drink deep, or taste not the Pierian spring: there shallow draughts intoxicate the brain, and drinking largely sobers us again.”
I feel pedantic today.Good quote by Boorstin

Milwaukee Bob

Well, all though the report’s conclusion does support “our” general position that we humans have a miniscule effect compared other forms of life on this plant, I think it’s for the wrong reason. Wherein, I think they (we) again have failed to comprehend the massiveness of the “system” we (or they in this case) are dealing with. The following is from a study done by the NSF and no, I do not have a link to the actual study –
Microbes to People: Without Us, You’re Nothing!
April 21, 2008
Nowhere is the principle of “strength in numbers” more apparent than in the collective power of microbes, which include bacteria, viruses, some fungi and some animals that can only be seen with microscopes.
Although each microbe is but an almost weightless one-celled organism, the collective weight of Earth’s 5 million-trillion-trillion microbes accounts for most of the planet’s biomass–the total weight of all living things. Even the total number of stars in the universe (7 thousand-billion-billion) pales in comparison to the number of microbes on Earth.
With their mighty collective muscle, microbes control every ecological process, from the decay of dead plants and animals to the production of oxygen. Therefore, it is fair to say that in important ways, microbes literally run the world.
No corner of Earth escapes the influence of microbes, the oldest living organisms on Earth. Since microbes first appeared 3.5 billion years ago, about one billion years after Earth formed, they have diversified enough to colonize every ecosystem, from scalding vents at the bottom of the ocean to burning desert sands to polar ice.
Microbes are in the food we eat, the air we breathe and the water we drink. Each liter of sea water contains up to a billion bacteria.
Microbes even inhabit the human body. In fact, every person has more than 10 times as many microbes living on and inside their body as human cells. Although most frequently associated with disease, our microbial hitchhikers help us much more than they harm us. How? By controlling many of the biological processes that are essential to our survival, including the maintenance of our skin and the digestion of our food. Each person’s digestive track alone harbors about three pounds of bacteria.
“If all of Earth’s microbes died, so would everything else, including us,” says Matt Kane of the National Science Foundation. “But if everything else died, microbes would do just fine.” Therefore, Kane concludes that “we need microbes more than they need us.”
Despite the importance of microbes, scientists have only been able to study less than one percent of the estimated millions of microbial species that live on Earth. Why so few? Because microbes have strict nutritional requirements and interact with one another in complex ways that currently make it impossible to grow the overwhelming majority of them in the laboratory.
— Lily Whiteman, National Science Foundation

Considering how LARGE that mass of life is, why do we think we can measure or much less project from a small sampling, accurately, any negative/positive change?
Statistically and logically, there is no way to know if the data points derived from your extremely limited sample are the same (or can be extrapolated to the whole) as would be derived from a majority of the mass.
Our mistake is in applying mathematics (digital analysis) to highly complex analog systems and then blindly believing that’s the way the real world works. It doesn’t!

C. Bruce Richardson Jr.

That’s interesting but it appears to be based only on modeling. They had to make certain assumptions in designing the model.

Ed Caryl

Jim
“Tree roots growing through limestone.”
http://www.redrockcanyonopenspace.org/page65.html
No. It’s purely mechanical. Small root hairs grow into small cracks going after moisture, then grow bigger.

Milwaukee Bob

Jimbo says:
April 28, 2010 at 5:48 am
Co2 is lumpy,…..
Jimbo, thanks for that reference, been looking for something like that for years, knowing there is no way CO2 is a “well mixed gas” as REQUIRED by the GW models to work. Already on its way to a programming guru who thinks the sun and moon rise and set because of computer models.

Stacey

“When we developed a model based on the actual biology of soil microbes, we found that soil carbon may not be lost to the atmosphere as the climate warms,” said Matthew Wallenstein of the Natural Resource Ecology Laboratory at Colorado State University. “Conventional ecosystem models that didn’t include enzymes did not make the same predictions.”
Why not carry out an experiment and measure CO2 emissions from soils at different temperatures. Is that too easy?

John Galt

Pamela Gray says:
April 28, 2010 at 6:09 am
I don’t think this will be a game changer at all. We are talking about such a small change in an already extremely small percent of atmospheric gases that this will never be observed as a measurable event. It will always and only exist in models. An educated guess with no statistical difference to be had. And mother nature cares not one red cent for models. That is the real game changer.
My opinion, this is not anywhere near a study you can hang your hat on. And it appears that the researchers are grasping for straws, though they may not have intended it to look that way.
It does however, point out the amusing belief by AGW enthusiasts the notion that microbe emissions under warmer temperatures would be worse than we thought! It is a rather silly study used to refute a rather silly notion.

It likely won’t be a game changer because it will be ignored. When ignoring fails, it will be summarily dismissed.
However, it may be one more thing the climate models got wrong. As always, this study needs to be followed up by others to validate the conclusions.

Douglas DC

At least the paper got published. Ten years ago even six months ago this may not have seen the light of day. Hmmm….

Chris Riley

“This could be a game changer” Well put.
In that soil respiration is about an order of magnitude larger than fossil fuel emissions, any small deviation from from the assumption that plant respiration + soil respiration equals plant assimilation ( minus actual growth in biomass carbon) would would require a rethinking of the impact of current emissions of CO2 on future concentrations of CO2 in the atmosphere. Another recalculation would involve the expected net flux of energy, as a portion of the energy we receive from the sun would be stored in the soil. Could it be that the fossil fuel cycle is the largest (in absolute terms) recycling project ever imagined.
I have no idea of what, (if any) attention the scientific and political communities will pay, or should pay, to this paper. Time will tell. I will say that it is heartening to see that an Assistant Professor, Stephen Allison, who presumably does not yet have tenure, has the courage to produce this kind of work, and in the UC system of all places. Courage has, and will always be, a scarce commodity. There is Hope.

Nandheeswaran Jothi

anthony,
this study needs to be taken with a whole bunch of salt. When the temperature of a specific area changes ( up or down ), some of the native species of fungi and other soil living life forms ( microbes, predominantly ) move to more hospitable area, but others that are better suited for the new environment invade very quickly. But, the overall Biota should increase. once they stabilize, you will see an increase in CO2 emissions again. That lag period might be a few years, but not much mor ethan that.
You should expect, as chemistry demands it for exothermic reactions, there should be an increase of CO2 emission from ground.
having said that, I think we know so little about this, and the Alarmists have been making all sorts of assertions, I welcome this paper. however, this sorts out in the long run, this kind of real science needs to be injected back into the debate. otherwise the alarmists will con the world into spending trillions on companies they run and control.

Enginer

I have >neveris< a relationship…) In this case soil humics, fulvic acid, other soil organics are the result of a warm, CO2 rich environment.
Experts have mentioned that for the last 100 years we have been mining carbon from US soils. No-till agriculture is a misdirected attempt to reverse this process. Proper soil cultivation can increase the soil organics, especially in a higher warmth,CO2 environment.
Didn't youse guys learn [i]anything[/i] from the discussions about Terra Preta?

steveta_uk

The report on the on The Register implied that quite a bot more warmth was required to inhibit the microbial growth.
So perhaps the believer’s response will be that this will only kick too late, well past the 6C rise they expect by 2100.

Spector

RE: Baa Humbug : (April 28, 2010 at 6:16 am) “The greatest obstacle to discovery is not ignorance — it is the illusion of knowledge!”
I think the problem here is that ‘the illusion of knowledge’ may be all any of us really have. Perhaps one of the more profound statements is that the universe may not only be stranger than we know, it may be stranger than we can possibly comprehend.

Co2 Insanity

Saw the comment about Firefox. Works fine on chrome and I like the new format. Works fine on Android, too.

Henry chance

More tax fraud in carbon trading? I suspect there is a motive to cheat.
If anyone thinks the carbon schemes will pay off the farmer that raises plants, they are crazy. Too many handlers in the chain that will beat the farmer to the money.

Milwaukee Bob

David Middleton says:
April 28, 2010 at 6:28 am
To all of your questions about carbon flux – NO! The human race has no clue to what the real world in and outs are, from whence it comes, where it goes or what the balance is at any given point in time. It’s all postulations by computer model based on a miniscule number of data points, with virtually no history other than analysis of sediments and ice cores. Until just a few months ago, when satellites proved the contrary, (for the first time!) supposedly the majority of atmospheric scientists (and GW modelers) believed CO2 was a well mixed gas. It is not and we have no reason/study/data to pin a belief on that it ever was or will be.
http://www.jpl.nasa.gov/news/news.cfm?release=2009-196

The surface of the planet is 5/6 water, which also contains microbes and other carbon-cycling organisms. What is the ratio of marine CO2 emissions to anthropogenic? Must be 50-to-1 at least. And how does that vary across location and time?
The depth of what we don’t know is abysmal.

hunter

The models did not account for a major source of CO2 properly, yet they are still considered reliable.
That reliability is not justified. And this is but part of a list of things the models do not get correctly.
AGW is to climate science what tulipomania was to horticulture.

geo

Do we know if the AGW computer models have even been trying to include the old understanding? They seem remarkably willing to just assume hard-to-determine stuff into irrelevance.
Since these are living organisms, Darwin cannot be ignored. Loss of efficiency may only be temporary. But then how long is “temporary”, even if true? Darn those fussy little details!

Tom in Co.

This “new finding” is taught in undergraduate level soil science and petroleum geology. All carbon, that is complexed in plant material, returns back to CO2 either by respiration or oxidation. The only exception to that is the small amount of plant material that happens to be buried in an inoxic environment, this material can eventually become coal oil and natural gas with enough heat and time. This is all part of the carbon cycle.
The biggest unknown in my mind with this cycle, is the generation of carbonate sediments in the ocean (that which becomes limestone). It would make sense that if the CO2 content in the ocean were to increase that the rate of carbonate sediments would also increase, but I have not seen any quantification of this process sensitivity. If this were true it, could be the biggest negative feedback of all.

pettyfog

First, I dont understand the ‘Negative Feedback’ element. Used to seeing CO2 stated as ‘positive’ feedback by the warmists.
– Which it doesnt seem to be, unless you can use a chain to push a cart. But how is a ‘moderating output’ negative?*
Second, as stated above, there’s a universe of microbial diversity and many would favor the warmer soils and multiply faster than their predecessor dominants. So that little bump in CO2 output might occur over and over as different variants emerge over time.
* However that should be offset by the greening effect of a richer soil, right? Nature’s Balance! When them little soil bugs in the Sahara start replicating like crazy.. WE BE HAPPY!
—————————————————————

Models, models everywhere and none that I can trust. (sorry STC) This is just another model and proves nothing. Models can only support or cast doubt, sometime they explain. At least this one takes into account the reality of living systems. Living systems do not function in a liner fashion for very long. Most living and probably most if not natural systems are always striving for equilibrium. They never quite achieve it for very long but just keep trying. That is much like people of science. We never do get all our questions answered we just keep trying. In short the more complex the problem the more complex the understanding of it.

We are all profoundly ignorant about most stuff. Which is why idiotic Chicken Little-type assumptions from the Gore school of nonsense science should be seen for what they are. ‘The Cat In The Hat’ by the late Dr Seuss makes more scientific sense than Al Gore’s followers.
Living in the UK is quite dispiriting now, as a little over a week away from an election the three majoe political parties trumpet their desperation to reduce ‘our’ carbon footprint when what they really mean, as they jet off to another photo-opportunity, is reducing my carbon footprint and enlarging theirs.

Enneagram

Pamela Gray says:
April 28, 2010 at 6:09 am
Brad says:
April 28, 2010 at 6:26 am
A kind of pesky microbes called HUMANS breath oxygen and exhale CO2, at an average amount of 900 grams (1.98 lb) per day.
This oxygen, as we all know, is to oxidize Fe+2 contained in blood’s hemoglobin (venous blood) to Fe+3 (red compound-arterial blood-) , while carbohydrates oxidation (burning=combustion) produces CO2. These are redox reactions (oxidation/reduction).
Only fools believing themselves Fool-Gods could pretend to intervene in such a complex system. Oh! I forgot it, as HE invented the Internet he is able to meddle in any operating system, no matter how complex.

JJB

AGW could lead to a shortage of CO2! The plants will starve! This is the final tipping point – we’re all doomed!
😉

Erik

@beng says:
April 28, 2010 at 5:48 am
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The new format doesn’t show well on my Firefox browser.Much slower loading too.
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No problem with these browsers, try empty your disk catch
Firefox 3.6.3
Opera 10.51
Google Chrome 4.1.249.1064