Greenhouse gas 'bookkeeping' turned on its head

March 9, 2016
Credit: NASA

For the first time scientists have looked at the net balance of the three major greenhouse gases—carbon dioxide, methane, and nitrous oxide—for every region of Earth's landmasses. They found surprisingly, that human-induced emissions of methane and nitrous oxide from ecosystems overwhelmingly surpass the ability of the land to soak up carbon dioxide emissions, which makes the terrestrial biosphere a contributor to climate change. The results published in the March 10, 2016, Nature, revises our understanding of how human activity contributes to global warming.

Co-author Anna Michalak of Carnegie's Department of Global Ecology remarked, "Typically we think of land as a net 'sink' of carbon dioxide. But we found that the sign of the human-induced impact is reversed if we also take into account methane and nitrous oxide."

The scientists looked at the so-called biogenic fluxes or flow of the three greenhouse gases on land that were caused by human activities over the last three decades and subtracted out that existed "naturally" during pre-industrial times. Biogenic sources include from plants, animals, microbes, and the like. They were interested in finding out how human activities have changed the biogenic fluxes of these gases. Historically, such emissions have included methane emissions from wetlands and from soil. Human activity and human-caused have changed the magnitude of these fluxes, however, as well as added new categories of biogenic fluxes such as those resulting from sewage, cattle, and fertilizer use.

The scientists first added up all biogenic emissions of carbon dioxide, methane, and nitrous oxide, then subtracted out those that occurred naturally prior to human intervention to get to the net amount. The study did not include non-biogenic gas emissions from activities like fossil fuel burning or natural gas production.

The team discovered that the human impact on biogenic methane and nitrous oxide emissions far outweighed the human impact on the terrestrial uptake of carbon dioxide, meaning that humans have caused the terrestrial biosphere to further contribute to warming. In other words, the terrestrial biosphere, through human action, is now contributing to climate change rather than mitigating climate change. This runs counter to conventional thinking based on previous studies, which had focused only on and had emphasized the climate change mitigating effect of human impacts terrestrial carbon uptake.

The scientists found that vary considerably by region. Interestingly, the human-induced emissions of the gases in Southern Asia, including China and India, had a larger net warming effect compared to other areas. Southern Asia contains some 90% of the world's rice fields and more than 60% of the world's nitrogen fertilizer use. Thus, in this region are largely from rice cultivation and livestock, while man-made fertilizers are a major source of .

Lead author of the study, Hanqin Tian director of the International Center for Climate and Global Change Research, School of Forestry and Wildlife Sciences at Auburn University said, "This finding reveals for the first time that human activities have transformed the land biosphere to a contributor to climate change."

"This study should serve as a wake-up call to governments, policymakers, and individuals around the world," said Michalak. "We must expand our focus and devise strategies that target the biogenic emissions of these other greenhouse gases if we are to change the course of climate change."

Explore further: A lower limit for future climate emissions

More information: The terrestrial biosphere as a net source of greenhouse gases to the atmosphere, Nature, DOI: 10.1038/nature16946

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33 comments

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rodkeh
1.5 / 5 (16) Mar 09, 2016
There is no science to support the theory of the Greenhouse Effect. There are no such thing as greenhouse gases, so all of this is just unfounded, wild and unjustified speculation.

Show us some real science!
rodkeh
1.3 / 5 (13) Mar 09, 2016
In 1856, Eunice Foote proved, that CO2 absorbs solar radiation, which means that CO2 actually produces a reverse greenhouse effect, that actually reduces the amount of solar radiation reaching the ground. Furthermore, since the molecules of CO2 in the atmosphere are already saturated with solar radiation, they can not possibly absorb more radiation from the ground, so that would tend to "increase" ground radiation. This proves, that increased levels of CO2 in the atmosphere in fact, reduces the solar effect, ergo, solar energy has absolutely nothing to do with global warming or climate and there is no such thing as a greenhouse effect or anything that resembles the contemporary theory.

When will anyone be willing to use their heads and listen to the voice of reason?
Phys1
4.4 / 5 (14) Mar 09, 2016
The voice of reason is someone from 1856? Or is it you?
Are you suffering from delusions of grandure ?
rodkeh
1.8 / 5 (10) Mar 09, 2016
Delusions of grandure? Oh, you mean grandeur!

Boy, are you easily impressed!
Ojorf
4.2 / 5 (10) Mar 09, 2016
No, "grandure", as in "manure". ;-)

leetennant
4.4 / 5 (14) Mar 09, 2016
The voice of reason is someone from 1856? Or is it you?
Are you suffering from delusions of grandure ?


He's peddling this crap in another thread as well. In this one he goes even further, arguing that there are no greenhouse gases. Foote's work preceded Tyndall's in establishing that CO2 WAS a greenhouse gas. He's basically taking her groundbreaking work and saying it says the exact opposite of what it does. That's akin to arguing that Einstein's work disproved relativity.
rodkeh
1.4 / 5 (9) Mar 10, 2016
The voice of reason is someone from 1856? Or is it you?
Are you suffering from delusions of grandure ?


He's peddling this crap in another thread as well. In this one he goes even further, arguing that there are no greenhouse gases. Foote's work preceded Tyndall's in establishing that CO2 WAS a greenhouse gas. He's basically taking her groundbreaking work and saying it says the exact opposite of what it does. That's akin to arguing that Einstein's work disproved relativity.


I see your peddling the same denial crap in another thread.
Gigel
3.4 / 5 (5) Mar 10, 2016
Gases are generally greenhouse gases as they absorb infrared radiation; e.g. oxygen, nitrogen, water vapour are gh gases. Also, the fact that they absorb radiation from the Sun actually increases the gas temperature, going the same way as the greenhouse effect.
KelDude
4.4 / 5 (7) Mar 10, 2016
@rodkeh What drivel! You are demonstrating your grade 6 education with your comments.
rodkeh
1 / 5 (4) Mar 10, 2016
Gases are generally greenhouse gases as they absorb infrared radiation; e.g. oxygen, nitrogen, water vapour are gh gases. Also, the fact that they absorb radiation from the Sun actually increases the gas temperature, going the same way as the greenhouse effect.


How can someone who knows absolutely nothing about science, think they can comment of scientific issues?
antigoracle
3 / 5 (4) Mar 10, 2016
China and India, had a larger net warming effect compared to other areas. Southern Asia contains some 90% of the world's rice fields and more than 60% of the world's nitrogen fertilizer use

And so, the population control agenda rears its ugly head.
tblakely1357
3 / 5 (2) Mar 12, 2016
And so it goes. Seems you can't trust anyone to not sell out.
brianamperesmith
3.9 / 5 (7) Mar 13, 2016
Don't people understand basic, established physics? Are people really denying the existence of the greenhouse effect? Carbon dioxide absorbs outgoing terrestrial radiation in a spectral region that is otherwise transparent to this radiation. Water and other atmospheric gases attenuate radiation in other regions of the spectrum. It's important to note that the physical basis is worked out in undergraduate physical chemistry applications. The main idea is that the peak intensity of the outgoing radiation overlaps with a strong absorption due to the asymmetric stretching of the carbon dioxide molecule. Water, nitrogen etc.. lack this spectroscopic feature. Also water cycles through the atmosphere in weeks or days while carbon dioxide resides for years. Temperature/concentration effects on the spectral features are well understood using undergraduate statistical mechanics. The argument that carbon dioxide bands are saturated is easily refuted by application of Beer's law.
Captain Stumpy
4 / 5 (4) Mar 13, 2016
Don't people understand basic, established physics?
@Brian
yes and no
on one hand, there are those who understand the physics, but ignore it for ideology, conspiracy, religion, politics or other reasons, as you note in the other thread
see: http://journals.p....0075637

http://arstechnic...nformed/

then there are those who are actually paid not to understand
http://www.drexel...nge.ashx

http://phys.org/n...ate.html

and because this site has no moderation, you will find the trolls and idiots like to hang out here posting abject stupidity against the science (any really, but the anti-AGW & anti-warming climate change crowd is the worst full of the stupidest ... except for maybe the creationists)

vlaaing peerd
1 / 5 (1) Mar 14, 2016
Don't people understand basic, established physics?


yes, but understanding basic physics and accepting to drop your cognitive bias are two very different things.
antialias_physorg
5 / 5 (3) Mar 14, 2016
yes, but understanding basic physics and accepting to drop your cognitive bias are two very different things.

Well then - if you have no problem with the former, why are you having so much trouble with the latter?

Dropping your bias should follow directly from accepting the physics, because physics isn't biased.
vlaaing peerd
1 / 5 (1) Mar 14, 2016

Well then - if you have no problem with the former, why are you having so much trouble with the latter?

Dropping your bias should follow directly from accepting the physics, because physics isn't biased.


I wasn't talking about myself ;)
antialias_physorg
3 / 5 (2) Mar 15, 2016
I wasn't talking about myself

That's the real problem right there. Because the one with the bias is you. You don't take the physics at face value but reject it in favor of ideology (read: personal bias).

It's really weird that you actually see the problem (bias) but don't realize what bias actually is.
vlaaing peerd
not rated yet Mar 15, 2016
I wasn't talking about myself

That's the real problem right there. Because the one with the bias is you.


What remark have I made that shows any bias towards (the validity of) this article?

Come on man, relax. you're taking your role as guardian of the scientific method way too seriously.
rodkeh
1 / 5 (3) Mar 15, 2016
Don't people understand basic, established physics?


You obviously don't! I love your description of the greenhouse effect!

Are you a Yank?
rodkeh
1 / 5 (2) Mar 15, 2016
Don't people understand basic, established physics?


You obviously don't. You can't even get a simple thing like The Greenhouse Effect theory right. Anyone with any scientific background knows your lying.

You're not fooling anyone!
brianamperesmith
5 / 5 (3) Mar 15, 2016
You are correct (I was incorrect). The primary vibrational mode responsible is not the asymmetric stretch. It is the bending mode which couples very well to the translational modes of other non ir active molecules. This also partially the reason increasing carbon dioxide at present concentrations does not follow Beer's law.

Guess I will give back the doctorate. Also my 98 percentile ranking on the GRE physics exam is very suspect now. If I am mistaken about a minor detail it obviously follows that the climate sensitivity range accepted by the vast majority of scientists working in the field must also be wrong.

Did you know: many complicated phenonema can't fit on a Fox News banner?
rodkeh
1 / 5 (3) Mar 15, 2016
I wasn't talking about myself

That's the real problem right there. Because the one with the bias is you. You don't take the physics at face value but reject it in favor of ideology (read: personal bias).

It's really weird that you actually see the problem (bias) but don't realize what bias actually is.


There's always a few of you on every forum. You claim to be authorities on subjects of which you have no clue.

Being able to Google does not make you an authority!
rodkeh
1 / 5 (2) Mar 15, 2016
You are correct (I was incorrect). The primary vibrational mode responsible is not the asymmetric stretch. It is the bending mode which couples very well to the translational modes of other non ir active molecules. This also partially the reason increasing carbon dioxide at present concentrations does not follow Beer's law.

Guess I will give back the doctorate. Also my 98 percentile ranking on the GRE physics exam is very suspect now. If I am mistaken about a minor detail it obviously follows that the climate sensitivity range accepted by the vast majority of scientists working in the field must also be wrong.

Did you know: many complicated phenonema can't fit on a Fox News banner?


What a joke! Dream on!
brianamperesmith
5 / 5 (3) Mar 15, 2016
Thanks. You provide true clarity. If you understand modern physics, chemistry astronomy etc.. it allows you to comprehend the details of climatology. Topics like radiation transfer, absorption and emmission of radiation by atoms and molecules allow one to understand subjects outside one's immediate area of research. The physics is the same. The language (abstract mathematics) invariant principles, are fixed.

That's the beauty of modern science. Heat flow, energy baalance, computer modelling of dynamic systems employ a common language and common methodology. That said, the modern understanding of climate rests on on fundamental basic physics that we the end user apply every day in our lives. How else do we move all the 1's and 0's around? Magic?
brianamperesmith
5 / 5 (3) Mar 15, 2016
What am I missing? Help me understand. In university I worked on energy transfer in condensed matter. The modelling relied on similar algorithms used in climate models. The reason I seem dismissive is that most often unreasonable skeptics are well-unreasonable-and not only seem to want to critique the very basics (i.e. carbon dioxide absorbs strongly in a region important to our earth/atmosphere heat balance) they want to criticize the more subtle aspects that are definitely way over their heads. With very few exceptions the so called arguments are just plain wrong, they use mutually contradictory arguments and completely misinterpret the theories and the evidence. Often it is sadly apparent that they don'the grasp
the bread and butter of modern physical science. Yet they (the skeptic) not knowing the difference between Planck and Wien much less Arhenius and Tyndall is going to reject everything and claim conspiracy. Is this the part where I insult your personhood? Incorrect?
rodkeh
1 / 5 (3) Mar 16, 2016
What am I missing?


Just about everything by the look of it. You are obviously full of it! If you studied at university, I'm going to win the next Lotto MAX.

You know nothing of the subject. Eunice Foote, in 1856, proved beyond any shadow of a doubt, that CO2 absorbs solar radiation, which proves there is no Greenhouse Effect. Which means that "solar radiation" has nothing to do with "climate". This meaningless twaddle about specific IR wavelength is irrelevant. If the atmospheric CO2 is already saturated with solar energy, it can not possibly absorb more terrestrial radiation any more than it can absorb more solar radiation. The Greenhouse Effect theory is utterly ridiculous! And so are You!
brianamperesmith
5 / 5 (2) Mar 16, 2016
Carbon dioxide absorbs in the IR not in the visible. Scientists in the 1890s did not have methods or theory to understand what is now-basic physics-that one learns as an undergraduate today. If carbon dioxide absorbed in the visible the atmosphere would be colored and opaque depending on where in the visible part of the spectrum it aborbs. It is not possible for our atmosphere to be saturated and for the green house effect to not occurr. "Saturation" means that the absorbing species is sufficiently concentrated along a radiative depth that all the energy in a specific region that can be absorbed by that species has been absorbed. We measure this as heat. If carbon dioxide were saturated the Erath would experience a runaway greenhouse effect and adding more carbon dioxide would still increase atmospheric temprature due to the thermodynamics of radiative transfer. Adding CO2 to Venus would still increase heat.
brianamperesmith
5 / 5 (3) Mar 16, 2016
So..you started off stating something imprecise and not true then stated two points that are mutually contradictory only to conclude with another point that is definitely not true. The interaction of matter and radiation as it applies here is an exact science and can be found in any undergraduate text physical chemistry methods.
I honestly do not care if global warming is a hoax (I've no children) I simply want people to do their homework before they spout off about things.
Finally, did you realize without carbon dioxide earth would be freezing cold? It and other green house gases absorb the outgoing infrared radiation. Each photon absorbed causes them to be vibrationally excited. This is heat. The correspondence between Earth's atmospheric concentration (CO2) and temperature is born out by ice core samples and sedimentary analysis, independently.
brianamperesmith
5 / 5 (2) Mar 16, 2016
Finally, one can measure where in the spectrum something something absorbs, then compare this to the spectrum of incoming solar radiation and outgoing terrestrial radiation. Any overlap means energy is transfered to the molecules. Higher energy visible/ uv light causes excitation of the electrons resulting to changes in the electronic configuration. IR absorption results in vibrationall motion of nuclei along bonds. This is heat. The atmosphere is transparent to visible radiation because the energy necessary to excite the electronic states of simple molecules like O2, N2 and water is in the ultraviolet. Where in the spectrum absorption takes place is exactly understood and can be calculated, along with the amount of attenuation. How this energy is dissipated is also exactly understood (meaning theory and experiment agree). That's how rotational excitation in a microwave heats food and how the greenhouse effect works.
brianamperesmith
5 / 5 (1) Mar 16, 2016
The reason Foote got it wrong was that her work predated the experimental and theoretical tools to either understand the mechanism(s) of radiatIive processes in atoms and molecules plus the methods of Fourier (heat tansfer), Boltzmann (statistical thermodynamics) and later modern radiative transfer as it applies to our atmosphere. Had she known more she would have realized: 1. Carbon dioxide IR absorption bands are not saturated. 2. If they were saturated adding more to the atmosphere would still result in additionally heating because the tropopause moves outwards in order to maintain energy balance. Both points are incontrovertible. So..the take home point is that the greenhouse effect cannot be false AND co2 bands be saturated. Saturation means energy transfered and contained in the atmosphere (heat). Get it?
brianamperesmith
5 / 5 (1) Mar 16, 2016
Also, solar radiation has everything to do with climate since this is the primary source of energy which drives all atmospheric processes. Differential heating of earth is what makes weather and climate. At any given time climate is changing as it has in the past it will in the future. Nature does what it does.

The reason scientists are concerned is that rapid change in global mean temperature even by a seemingly small amount over just a few decades is already having dramatic consequences and is unprecedented over recorded history. The fact that co2 levels are the highest they have been in millions of years should give one pause.
brianamperesmith
5 / 5 (1) Mar 16, 2016
Finally, at university everyday, I used spectroscopy to formulate and understand energy transfer and dissipation. The study of the co2 spectrum is what is studied at the undergraduate level using FTIR in courses I taught. I performed laser Raman epectroscopy using co2 lasers whose basis of operation relies on a deep understanding of terms like "saturation" and directly related to understanding the greenhouse effect and it's correspondence to anthropogenic heating.

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