EPA document supports ~3% of atmospheric carbon dioxide is attributable to human sources

NOTE: this post has an error, see update below. – Anthony

From a Wry Heat reprinted with permission of Jonathan DuHamel

A new post on The Hockey Schtick reviews a new paper “that finds only about 3.75% [15 ppm] of the CO2 in the lower atmosphere is man-made from the burning of fossil fuels, and thus, the vast remainder of the 400 ppm atmospheric CO2 is from land-use changes and natural sources such as ocean outgassing and plant respiration.”

This new work supports an old table from the Energy Information Administration which shows the same thing: only about 3% of atmospheric carbon dioxide is attributable to human sources.  The numbers are from IPCC data. 

Look at the table and do the arithmetic: 23,100/793,100 = 0.029.

URL for table: http://www.eia.doe.gov/oiaf/1605/archive/gg04rpt/pdf/tbl3.pdf

EPA_Table3pct

If one wanted to make fun of the alleged consensus of “climate scientists”, one could say that 97% of carbon dioxide molecules agree that global warming results from natural causes.

===============================================================

UPDATE:

Thanks to everyone who pointed out the difference in the chart and the issues.

I was offered this post by the author in WUWT Tips and Notes, here: http://wattsupwiththat.com/tips-and-notes/#comment-1696307 and reproduced below.

The chart refers to the annual increase in CO2, not the total amount. So it is misleading.

Since the original author had worked for the Tucson Citizen I made the mistake of assuming it was properly vetted.

The fault is mine for not checking further. But as “pokerguy” notes, it won’t disappear. Mistakes are just as valuable for learning. – Anthony Watts

wryheat2 says:

July 28, 2014 at 12:28 pm

Mr. Watts,

John Droz suggested I contact you.

On my blog, I commented on the reasearch by Denica Bozhinova on CO2 content due to fossil fuel burining. She apparently scared The Hockey Schtick into taking down his post on the matter. However, there is an older table from EIA which I reproduce on my post.

Denica Bozhinova has commented extensively, and frankly, I can’t understand her position since she seems to contradict what she wrote in the abstract to “Simulating the integrated summertime Ä14CO2 signature from anthropogenic emissions over Western Europe”

See my post here (you may reprint it if you wish):

http://wryheat.wordpress.com/2014/07/19/only-about-3-of-co2-in-atmosphere-due-to-burning-fossil-fuels/

Jonathan DuHamel

Tucson, AZ

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David in Cal

Note that this result does NOT contradict the likelihood that the increase in CO2 from 300 ppm to 400 ppm was caused (or mostly caused) by man’s emissions.

Great moment of honesty.
I am not signing for that methane metric. Total sources are not known. Plants release methane in UV light from the sun, which is variable. Methane is released from reserves in the seafloors.
This reminds me of the Josh cartoon, “Stages of Grief” —
http://catallaxyfiles.com/files/2012/07/climate-grief_scr.jpg
“Er, methane?”

“A new post on The Hockey Schtick reviews a new paper “that finds only about 3.75% [15 ppm] of the CO2 in the lower atmosphere is man-made from the burning of fossil fuels, “
The new paper said nothing of the sort. HS disappeared the entire thread.

glenncz

the Hockey Schtick link doesn’t work.
Possibly because the blog post was retracted. The chart does not say that 3.75% of the 400ppm is man-made. Those numbers in the charts refer to annual emissions. The theory is that earth was in a perfect balance before mans fossil emissions and now 50% of that 3.75% is what is causing the 2-3 annual ppm rise in CO2.
The above blog post should be rewritten or deleted.

jaffa68

Well, David in Cal – Looking at those figures its lucky we started pumping CO2 into the atmosphere or levels would have fallen below 100ppm by now and all the plants would have died.
Or maybe it’s not that simple, maybe climate scietivists haven’t accounted for every mechanism that has kept the climate remarkably stable for hundreds of millions of years.

glenncz says: July 29, 2014 at 12:27 am
“the Hockey Schtick link doesn’t work.
Possibly because the blog post was retracted.”

The first comment at the Wry Heat link is from one of the authors:
“Denica Bozhinova July 23, 2014 at 2:04 pm
A reply from the authors of the scientific article on the “review” on The Hockey Schtick blog has pointed out that the results cited are grossly misinterpreted and the blog has taken down the entire review and following comments.”

Big oops moment?
Don’t fret, you can always fiddle with the figures for a set that better supports the theory.. Go ahead it is hardly considered to be unethical -, just supportive of the pre-established ” morally correct position on CAGW”.

“A reply from the authors of the scientific article on the “review” on The Hockey Schtick blog has pointed out that the results cited are grossly misinterpreted and the blog has taken down the entire review and following comments.”

Siberian_husky

Oh. My. God. You are stupid.

Anyway it is dated 2001 hardly relevant

Nigel Harris

I’d take this whole post down quickly before anyone else notices it. Confirmation bias much?

Wu

Excuse my ignorance but I thought plants INHALE CO2 and exhale Oxygen. Was my science teacher wrong? He was a tad old to be frank.

Leo Morgan

This post is an embarrassing moment for us sceptics.
As others have mentioned above, this refers to the annual increase in CO2, not the total amount there.
But this has always been a basic tenet of the alarmist’s case.
This does not show any conspiracy by the climate faithful, nor any fact concealed by them. It merely shows that the poster(s) have not understood what both sides have been talking about all along. I must clarify that- in fact its likely that the majority of the faithful do believe humanity is the sole cause of atmospheric CO2- but none of the educated among them do believe that.
The only thing that could make this more embarrassing would be if Anthony were to delete the post. Fortunately he has more integrity than that.
Kudos to all the sceptics who jumped on the mistake and pointed out that the post’s evidence does not support its headline claims.

Dr Ken Pollock

Wu, he was right but the message was incomplete. Plants do both – respiration and photosynthesis. The latter fixes CO2 and produces O2, the former uses energy and O2 to produce CO2 and water. All living things respire. Only green plants absorb CO2 to produce the food we all live off.

climatereason

Nick Stokes has already commented that the original article has been completely misinterpreted.
This current article is also therefore misleading and irrelevant
tonyb

M Courtney

This new work supports an old table from the Energy Information Administration which shows the same thing: only about 3% of atmospheric carbon dioxide is attributable to human sources.

But land use change (deforestation) is a manmade impact.

M Courtney

Oops, should have read the comments first.
This is not worth commenting on.
But fortunately most of my comments are not worth reading either so, fair’s fair.

Allen63

If Nature cut its production by roughly 1.5 percent, Mankind would be “off the hook”.
If Nature increases its production by roughly 1.5 percent, Mankind would have to cut its CO2 production to “zero” (to stop the “catastrophe”).
Seems like Mankind is not a big “player” — unless one believes Nature is so “balanced and invariant” that a 1.5 percent change in Natural CO2 is “out of the question”.

holts7

How about delete it off WUWT also!!!

Allen63 says: July 29, 2014 at 1:59 am
‘Seems like Mankind is not a big “player” — unless one believes Nature is so “balanced and invariant” that a 1.5 percent change in Natural CO2 is “out of the question”.’

It can’t be sustained, whereas our continual additions are. The plant biosphere, for example, has about 550 Gtons Carbon. Every year, it takes about 123 Gtons from the air via photosynthesis. 60 Gtons returns via plant respiration and 60 Gt by decomposition. It’s a big annual source, but came from the atmosphere in the first place. We’ve brought to the surface and emitted nearly 400 Gtons C. The plant biosphere can’t compete with that.
Likewise the ocean emits and absorbs 90 Gton/yr. That’s mainly seasonal. Water warms in Spring, and emits. It cools in autumn, and absorbs. It’s been going on for millions of years.

GeeJam

Sorry David in Cal, but 400 ppm is such a trivial amount of atmospheric gas when compared to all other gasses. 1 x million divided by 400 is 1 x 2,500th of all the air in the sky. It’s really not a lot.
By comparison . . . .
Nitrogen (N2) is around 780,800 ppm (nearly 1,952 times more than total CO2)
Oxygen (O2) is around 209,500 ppm (nearly 524 times more than total CO2)
Argon (Ar) is around 9,297 ppm (nearly 23 times more than total CO2)
Naturally occurring Carbon Dioxide (CO2) is around 388 ppm
Anthropogenic Carbon Dioxide (CO2) is only around 12 ppm (that’s about 1 x 83,000th of the atmosphere)– and yet it still seems to be widely believed that this microscopic amount of gas has dominated the warming of our Earth during the last century. Even UK vehicle excise duty (road tax) is calculated on how much we contribute to this 1 x 83,000th of the sky.
(Combined total for Neon, Methane, Helium, Krypton, Hydrogen and Xenon is around just 3 ppm)

johnmarshall

This claim is totally a guess. Volcanogenic CO2 is more plentiful than anthropogenic CO2 and both are isotopically identical. How can you differentiate?????

Alan Robertson

GeeJam says:
July 29, 2014 at 2:28 am
“Anthropogenic Carbon Dioxide (CO2) is only around 12 ppm…”
_________________________
You dropped a digit… 120ppm is more recognized figure.

richardscourtney

Nick Stokes:
You repeat the circular mass balance argument in your post at July 29, 2014 at 2:20 am.
Your post says

Allen63 says: July 29, 2014 at 1:59 am

‘Seems like Mankind is not a big “player” — unless one believes Nature is so “balanced and invariant” that a 1.5 percent change in Natural CO2 is “out of the question”.’

It can’t be sustained, whereas our continual additions are.

Really? “It can’t be sustained”? You know that?
There are many possible ways it could be “sustained” because almost all the CO2 circulating in the carbon cycle is in the deep ocean, and it is not known what rate of CO2 exchange occurs between deep ocean and ocean surface layer.
For example, a minute change to ocean surface layer pH of 0.1 would alter the equilibrium of CO2 between air and ocean to induce more change to atmospheric CO2 concentration than has been observed. Such a pH change could not be induced by alterations to CO2 concentrations and fluxes because of the carbonate buffer. But it could be a result of change to the sulphur injected into the thermohaline circulation by submarine volcanoes long ago. When the dissolved sulphur reached the ocean surface layer it would change the ocean surface layer pH with resulting change to atmospheric CO2 concentration. And such a global 0.1 pH change is far too small for the limited available data to indicate it.
I don’t know if the recent rise of atmospheric CO2 concentration (as observed at Mauna Loa since 1958) has a natural cause, an anthropogenic cause, or some combination of anthropogenic and natural causes but I want to know
(ref. Rorsch A, Courtney RS & Thoenes D, ‘The Interaction of Climate Change and the Carbon Dioxide Cycle’ E&E v16no2 (2005) ).
But I do know that the rise is NOT a simple accumulation of CO2 in the air as a result of the anthropogenic CO2 overloading the sinks for CO2: the dynamics of the seasonal variation of CO2 refute such accumulation.
If you want to support the circular mass balance argument then wait for the inevitable arrival of Ferdinand Engelbeen because he promotes it and his knowledge of it is supreme.
Richard

Nylo

I don’t think this should disappear from WUWT. Mistakes should be accounted for, not erased as if they never happened. It is only by keeping what was originally said that we can learn some humility, and help in not making similar mistakes so easily in the future. The correct procedure would be to edit the story warning at the beginning that there is some important error in it, and detailing it.

GeeJam

Slightly off topic but the following link about UK MP’s bickering over ‘climate reoport’ is worth reading.
http://www.bbc.co.uk/news/science-environment-28531091

GeeJam

Alan Robertson says:
July 29, 2014 at 2:47 am
“You dropped a digit… 120 ppm is more recognized figure”.
I’m puzzled. If (as you say) anthropogenic CO2 is 120 ppm, that’s over a quarter of all the total CO2 in the air. Thanks, but I’ll stick with the original figures. About 96.775% of all CO2 is naturally occuring. This leaves 3.225% man-made. I do not know where you got your 120 ppm from.

CodeTech

WUWT doesn’t “disappear” posts, and shouldn’t.
There is a nearly infinite capacity for the biosphere to absorb ANY conceivable amount of CO2 that human activity could possibly release. It’s automatic. The naive and, frankly, obtuse belief that there is some sort of “limit” on this is just ridiculous and bizarre, not to mention completely unscientific.
If CO2 levels get high enough, an entirely new level of plant life will remove all that is possible.
CO2 levels DO NOT control temperature. That is backward. But hey, go ahead and continue believing the fiction.

Jake

To GeeJam: It is well documented that atmospheric CO2 had been fairly constant at 280 ppm in the time prior to the industrial revolution, at which time CO2 has exponentially increased to its current level of just over 400 ppm. 400 – 280 = 120 …. sorry for the somewhat sloppy sig figs ;). I’m not sure you understand what the values are representing on the table provided.

Another Gareth

As others have pointed out this claim rests on considering annual emissions. Half of what is man made emissions this year becomes ‘natural’ the following year as the biosphere keeps expanding.

phlogiston

It would be a serious cause for concern if anthropogenic CO2 input to the atmosphere is not responsible for a significant fraction of the recent rise in atmospheric CO2 concentration.
CO2 starvation is a serious threat to the biosphere in the long term and, unlike moderate global warming, has the potential to cause extinction of life on earth.
Anyone interested in biosphere extinction scenarios should read Franck et al 2006:
http://hal.archives-ouvertes.fr/docs/00/29/75/42/PDF/bg-3-85-2006.pdf
This paper points out that CO2 starvation might cause biosphere extinction before heating from solar expansion.
Basically, without human intervention during the next glacial period, as in the last, CO2 levels can be expected to drop below 200 ppm and approach levels that will limit plant growth. Below 150 ppm and you are looking at major plant die-offs.
This might be a situation facing the world population in a few tens of thousands of years time. At that time it might literally be a matter of life and death whether or not we can materially increase CO2 in the atmosphere.
Thus if all the output of the world’s industry, power generation and transport at present is only increasing the atmospheric CO2 level by 3 percent or so, burning fossil fuel as fast as reasonably possible, it suggests we are at the mercy of oceanic exchange processes for CO2 and cant do much about it. This would be bad, not good, news.
Since over the long timescale we are moving toward deepening glaciation, this CO2 starvation scenario might become a reality within the next few glacial cycles.
For this reason I for one sincerely hope that Ferdinand Engelbeen is correct that a substantial fraction of the recent CO2 increase is indeed anthropogenic. If this view is correct it means humanity has some defense available against CO2 starvation, providing our technical-industrial knowledge and infrastructure are preserved.

Alan Robertson

GeeJam says:
July 29, 2014 at 3:11 am
Alan Robertson says:
July 29, 2014 at 2:47 am
“You dropped a digit… 120 ppm is more recognized figure”.
—————–
I’m puzzled. If (as you say) anthropogenic CO2 is 120 ppm, that’s over a quarter of all the total CO2 in the air. Thanks, but I’ll stick with the original figures. About 96.775% of all CO2 is naturally occuring. This leaves 3.225% man-made. I do not know where you got your 120 ppm from.
________________________
While the amount of man’s contribution to the rise in CO2 is controversial, 280 ppm/atm is the generally accepted concentration at the beginning of the industrial revolution.
Speaking of “don’t know where you got your figure from”… you are welcome (invited) to post evidence to support your claims.

glenncz says: July 29, 2014 at 12:27 am
The chart does not say that 3.75% of the 400ppm is man-made. Those numbers in the charts refer to annual emissions. The theory is that earth was in a perfect balance before mans fossil emissions and now 50% of that 3.75% is what is causing the 2-3 annual ppm rise in CO2.
The above blog post should be rewritten or deleted.

Retraction is no use – the harm is done. But your remark should be added to the original blog post.

dccowboy

Alan Robertson says:
July 29, 2014 at 3:34 am
“While the amount of man’s contribution to the rise in CO2 is controversial, 280 ppm/atm is the generally accepted concentration at the beginning of the industrial revolution.”
Alan, are you saying that since pre industiral revolution the CO2 concentration of CO2 was 280ppm and the concentration is ~ 400ppm, then that means that the entire increase (120ppm) is attributable to anthropogenic sources? If so, I am very ‘skeptical’ (or maybe ‘denial inclined’) about that idea. I suppose you could claim that the entire 120ppm is a result of anthropogenic activity and associated feedbacks, but even then I’d have to see some evidence that the proposed feedbacks actually exist.

Alan Robertson

dccowboy says:
July 29, 2014 at 3:45 am
Alan Robertson says:
July 29, 2014 at 3:34 am
“While the amount of man’s contribution to the rise in CO2 is controversial, 280 ppm/atm is the generally accepted concentration at the beginning of the industrial revolution.”
Alan, are you saying that since pre industiral revolution the CO2 concentration of CO2 was 280ppm and the concentration is ~ 400ppm, then that means that the entire increase (120ppm) is attributable to anthropogenic sources? If so, I am very ‘skeptical’ (or maybe ‘denial inclined’) about that idea. I suppose you could claim that the entire 120ppm is a result of anthropogenic activity and associated feedbacks, but even then I’d have to see some evidence that the proposed feedbacks actually exist.
_________
I did not make that claim and in fact, said that the attribution of the 120 ppm rise is controversial.

Oh brother, yet another thread wasted on trying to explain the obvious.
Here is a 5-year old paraphrase from David J. C. MacKay, professor of natural philosophy in the Department of Physics at the University of Cambridge,
The burning of fossil fuels sends seven gigatons (3.27 %) of carbon dioxide into the atmosphere each year, while the biosphere and oceans account for 440 (55.28 %) and 330 (41.46 %) gigatons, respectively. Total human emissions have jumped sharply since the Industrial Revolution; and it is this added atmospheric carbon that worries many. Yes, carbon is emitted naturally into the atmosphere but the atmosphere also sends carbon back to the land and oceans and these carbon flows have canceled each other out for millennia. Burning fossil fuels, in contrast, creates a new flow of carbon that, though small, is not cancelled.

This post and the comments that follow bring up some questions.
1) Why do we suppose that the CO2 concentration in the atmosphere before the industrial revolution was perfect? If it was not perfect then, what is perfect?
2) How much of the 400 parts per million is there because of nature and how much is really there because of mankind’s activities — and how sure of that are we?
3) What average temperature is perfect? How do we know that?
4) Has the earth ever had much more than 400 ppm of CO2 in the atmosphere? If so, did it lead to “runaway warming” leading to the devastation of life on earth?
5) Does more CO2 lead to a “greening effect” that gives us more plant mass? If so, does the more plant mass use up CO2 from the atmosphere? If so, is that a negative feedback to increased CO2?
I wonder if our understanding of the dynamics of all of this is on par with our lack of understanding of “continental drift” was back when I was in school. (now renamed “plate tectonics)

Geocraft had it at 3.225% – http://www.geocraft.com/WVFossils/greenhouse_data.html
Given the small percentage, I suspect both are in the ball park

markstoval says: July 29, 2014 at 4:04 am
This post and the comments that follow bring up some questions.
You have every right to ask those questions.
But when citing / quoting a paper, one should at the very least correctly convey what the authors’ claims are.

Johan says:
July 29, 2014 at 4:14 am
markstoval says: July 29, 2014 at 4:04 am
This post and the comments that follow bring up some questions.
You have every right to ask those questions.
But when citing / quoting a paper, one should at the very least correctly convey what the authors’ claims are.

I made no claim at all as to what the cited paper said. Why would you suggest that I had incorrectly conveyed the author’s claims?

markstoval says: July 29, 2014 at 4:20 am
I made no claim at all as to what the cited paper said. Why would you suggest that I had incorrectly conveyed the author’s claims?
Not you – I meant the original blog post. And it would seem that The Hockey Schtick already retracted their review, as numerous posters pointed out their blunder.

Of course, on a somewhat different and even more important note; what e.g. Nick Stokes has missed (or is perhaps unaware of) is that; for the stated rate and retention of anthropogenic (fossil-derived) CO2 in the atmosphere claimed by IPCC in AR4 to have caused the small drop observed in atmospheric δ13C, the initial atmosphere CO2 concentration would have been 2,913.9 GtC, some 3.8 times the figure used by IPCC. This is equivalent to 1,453 ppm of CO2 instead of 380 ppm!
The atmospheric 13C mass balance will agree with the measurements only if the atmosphere retains much less than 50% of the estimated anthropogenic emissions. The necessary retention is 13.1%, a factor of 3.8 less than the ~50% supplied by IPCC in AR4. The IPCC AR4 Figure 2.3(b) ‘Keeling Plot’ is fraudulent. They quoted Battle et al. (2000) but they didn’t botgher to read it.
The surge in CO2 seen in the last century was not caused by man (although it may well have been caused by global warming). The CO2 added to the atmosphere is far heavier than the weight attributed to anthropogenic CO2. The isotopic ratio for fossil fuel would have had to be considerably heavier; -13.657‰PDB instead of -29.4‰PDB, for the increase in atmospheric CO2 to have been caused by man. IPCC can’t even get their isotopic geochemistry right. Dig and ye shall find ‘curious’ literature contortions with the 13C data have continued right up into the last decade! Settled science…..not.
.

TimC

Sorry if I’m being dense, but are the numbers being discussed up-thread correct?
The “Table 3” chart above shows total (annual) CO2 emissions of 793,100 E6 metric tonnes of gas, being 770,000 E6 natural and 23,100 E6 anthro. If there were no anthro element the emissions would have been just the 770,000 E6 tonnes. Assuming (am I correct?) that absorption is essentially proportional to total atmospheric CO2, the pro-rata absorption would have been 758,640 E6 tonnes, with no athro element. So: without any anthro element these figures anyway show an annual increase of 11,359E6 tonnes.
Doesn’t this mean that the (suggested) anthro annual increase is just 340E6 tonnes, representing at most 3% of the natural annual increase and just 0.043% of total atmospheric CO2? How is it possible realistically to account for a signal as small as that?

Alx

The headline is mis-leading, alarmist claim most if not all of the increase in CO2 is man-made. The table presented shows that human contributions are ~3% of total CO2, then shows the effective increase is ~1.5%.
As wrong as the headline is, the alarmist claim that there would be little to no increase to the total CO2 without man-made CO2 contributions is equally wrong. The global system is dynamic not static with the only variable being humanity.
I do not think alrmist claims would even pass as circumstantial evidence in a court of law. If petty crime went up since Michael Mann was hired by his university, could Michael Mann be arrested as the cause?

Jimbo

Anthony,
If there is a mistake here then it should be stated now, and further comments are thus unnecessary.

MikeB

Although the conclusions drawn by the Hockey Schtick were a load of junk, the table produced by the IPCC is quite reliable. It gives the relative contributions of CO2 to the atmosphere from natural and human-made sources. This shows that the human contribution was about 3% during the 1990s. The figures are a little out of date, but won’t have changed much.
It is easy to see that, without the human contribution, the natural CO2 sinks on the planet could cope with CO2 naturally produced but when human-made CO2 is included these sinks are overloaded and there is an excess of 11,700 tonnes of CO2 left in the atmosphere each year.
So how does this increase of 11,700 tonnes per year compare to the increasing CO2 levels measured by the Mauna Loa Observatory each year?
The Mauna Loa figures show that CO2 concentrations are increasing at a rate of about 2 parts per million(by volume) per year.
Now the mass of the Earth’s atmosphere is about 5.1*10^15 tonnes so, in proportion, an increase of 11,700 tonnes per year represents an increase of 2.29 parts per million (by mass). So we can see that this is in the right ball park and conclude that the rise in CO2 levels of 2 ppmv per year is consistent with the human-made contribution of atmospheric CO2.
From another perspective, we know that a CO2 concentration of about 280 ppm is normal during interglacial periods like this one and this was the level before the industrial era. See ice core records…http://commons.wikimedia.org/wiki/File:Vostok-ice-core-petit.png
The level is now 400 ppm, the highest level for 800,000 years. In the absence of any other theories to the contrary, it is reasonable to suppose that the current enhanced CO2 levels are due to human activity.
This is not to say that there is a problem. Oil and Gas will run out long before we can double the current level ( at 2ppm per annum it will take 200 years) and, as the ‘pause’ indicates the sensitivity of the climate to CO2 is probably much less than the IPCC would have us believe. So increasing CO2 is as likely to be beneficial as it is harmful.

MikeB says:July 29, 2014 at 4:56 am
Although the conclusions drawn by the Hockey Schtick were a load of junk, the table produced by the IPCC is quite reliable.
Quite so, but I’m also sure mr. Anthony Watts knows very well the difference between “annual CO2 emissions in the atmosphere” and “annual CO2 concentration in the atmosphere”.
Then why repost that “load of junk” of the Hockey Schtick here? Very hight trust can be too much of a good thing.

GeeJam

philjourdan says:
July 29, 2014 at 4:10 am
“Geocraft had it at 3.225%”
Thanks for backing me up Phil (and reinforcing the link to Geocraft). Man-made CO2 is 3.225% of 400 ppm. If posters wish to highlight the significance of pre-industrial levels of CO2, then fine – but suggest you don’t leave it there. Why not go back 2,000 years to the Roman era when there was even less CO2, yet (according to research) it was considerably ‘warmer’ than it is right now. And they didn’t have carbonated drinks, decaffeinated coffee, welding coolant gas, air-con, dry-ice pellets, refrigeration, etc.
Even if anthropogenic CO2 was 5% of the total atmospheric CO2 (which it isn’t) then it’s still an incredibly miniscule amount when compared to all other gasses present in the air – and cannot be totally accountable for a 1 degree rise in temperature during the last century. It’s 26 degrees C here in central UK today. It was only 3 degrees C here in February. My super-human personal ability to adapt to a 23 degree temperature difference in five months is just astonishing! Nuff said.

JRM

Question, Mauna Loa ticks up 2ppm it seems every year, this does not come even close to mans increased output? If man caused it to increase 2ppm in the 60’s, should it now not be going up by 10ppm now as our output increases?

Latitude

here we go again……man emits a special CO2 that’s cumulative….plants, oceans, and chemistry can’t touch it
“CO2 levels can be expected to drop below 200 ppm and approach levels that will limit plant growth.”
Our current CO2 level is limiting to plants now….increase it in a greenhouse and plants grow faster

GeeJam says: July 29, 2014 at 5:21 am
Man-made CO2 is 3.225% of 400 ppm.
GeeJam, can you please tell us the difference between “CO2 emissions in the atmosphere” and “CO2 concentration in the atmosphere”, and in what units both are measured?