No Rise of Atmospheric Carbon Dioxide Fraction in Past 160 Years

[bik0]

To assess whether the airborne fraction is indeed increasing, Wolfgang Knorr of the Department of Earth Sciences at the University of Bristol reanalyzed available atmospheric carbon dioxide and emissions data since 1850 and considers the uncertainties in the data.

In contradiction to some recent studies, he finds that the airborne fraction of carbon dioxide has not increased either during the past 150 years or during the most recent five decades.

The research is published in Geophysical Research Letters.

http://www.sciencedaily.com/releases/2009/12/091230184221.htm

[FreakinDJ]

1. Wait until this is passed around Scientific Peer Review

he could have easily have cooked the numbers but we won't know until his calculations have been examined.

Just with the Claims of "Cold Fusion" - it don't mean shit until it can be verified

[bhikkhu]

4. Even when and if verified, its just refines the modeling

which is a good thing. Not that the planet isn't screwed anyway as far as CO2 levels go, its just a little less, maybe.

[rfranklin]

2. One man's opinion against that of of about one million others...

"Our maths here is somewhat coarse. Some better data suggests the ‘consensus’ figure is around 97.5% of publishing climatologists and around 90% of all publishing scientists supporting the human-induced climate theory."

http://www.informationisbeautiful.net/2009/climate-change-a-consensus-among-scientists/

[bhikkhu]

3. ...which is far less important than the measured rise in atmospheric CO2 ppm

what the article refers to is a possible flaw in the current modeling of the CO2 cycle, indicating that the natural carbon sinks may have a greater capacity than expected. Which has a small effect on the level of atmospheric CO2 levels projected out into the future by current models.

Nevertheless, average atmospheric CO2 levels still stand at a higher point today than they have been in the past 600,000 years, and are predicted to get steadily worse for many many years...

[Dead_Parrot]

9. It's interesting...

...to see who can tell the difference between atmospheric fraction of CO₂, and CO₂ fraction of the atmosphere. Since denialists usually have a pretty dim grasp of science, I expect this will going around for a while.

[tabatha]

10. Yes, "airborne fraction of carbon dioxide"

is the key phrase. It would probably have been better to say "percentage of carbon dioxide released that remains airborne" and that has not changed in 160 years.

[MH1]

16. Thanks for the clarification

for the non-scientists among us who nonetheless have open minds.

[tabatha]

5. This is somewhat misleading.

On edit - see post below.

[bhikkhu]

6. misleading = must-be-trumpeted-around, in some circles. n/t

[muriel_volestrangler]

7. What this says is that of man-made CO2, the same % builds up in the air, and the same % is absorbed

into either plants or the sea, every year. This is clear from the 1st 3 paragraphs:

Most of the carbon dioxide emitted by human activity does not remain in the atmosphere, but is instead absorbed by the oceans and terrestrial ecosystems. In fact, only about 45 percent of emitted carbon dioxide stays in the atmosphere.

However, some studies have suggested that the ability of oceans and plants to absorb carbon dioxide recently may have begun to decline and that the airborne fraction of anthropogenic carbon dioxide emissions is therefore beginning to increase.

Many climate models also assume that the airborne fraction will increase. Because understanding of the airborne fraction of carbon dioxide is important for predicting future climate change, it is essential to have accurate knowledge of whether that fraction is changing or will change as emissions increase.

Those 3 paragraphs are fairly clear; the 2 in the OP can be misinterpreted, if the 1st 3 aren't read.

So, if we emitted 1 billion tonnes of CO2 in 1 year, 450 million tonnes stayed in the atmosphere. Many years later, when we emitted 10 billion tonnes, 4,500 million tonnes stayed in the atmosphere. And the same proportion is still getting added to the CO2 in the atmosphere each year now. That's all this is saying.

[tabatha]

8. Yes, that is a correct explanation.

In other words, for the last 160 years, 45% of CO2 emitted remains in the atmosphere - i.e. the percent amount or fraction 45% has not changed.

However, the total amount has changed.

[JonQ]

11. The science is settled

stop unsettling it with new facts.

[tabatha]

12. There is nothing wrong with that article, and does not

undermine the science. It is only those who don't understand what is being said that will misinterpret it:

As Dead Parrot said: "It's interesting to see who can tell the difference between atmospheric fraction of CO2, and CO2 fraction of the atmosphere. Since denialists usually have a pretty dim grasp of science, I expect this will going around for a while."

[JonQ]

13. Except that people have been trying to make the claim

that as the globe warms more CO2 will be released from the oceans creating a feedback loop.

http://www.lbl.gov/Science-Articles/Archive/ESD-feedback-loops.html

So far the evidence does not support this additional hysteria.

[tabatha]

14. Your link is to a 2006 article.

And I don't think it has to do with a feedback loop - it has to do with the saturation of CO2 in water.

Watch this:
http://www.agu.org/meetings/fm09/lectures/lecture_videos/A23A.shtml

and listen to the last question.

[Name removed]

25. Deleted message

Message removed by moderator. Click here to review the message board rules.

[tabatha]

26. Mostly, I have read about methane feedback

where methane is not normally in the atmosphere in large quantities, and could be if thawing exposes large areas of methane producing vegetation normally under snow.

However, there is a feedback loop for any soluble green-house gas in water, because solubility decreases with increase in temperature - this has been known for a long time, long before global warming was studied.

Hence, if the temperature of the ocean rises, gases will be less soluble, and re-enter the atmosphere - and the fraction of 45% could increase. This will cause more warming of the atmosphere, and eventually of the water, and so more gas will be released to the atmosphere. If it has not happened up until now, it does not mean it cannot happen in the future when things get much hotter.

http://www.engineeringtoolbox.com/gases-solubility-water-d_1148.html

[depakid]

15. Errr... there re other greenhouse gasses besides CO2

and ones that are far more potent.

Not that you'd figure them into your denialist equations.

[tabatha]

20. This is not a denial - fraction is not the same as total amount.

And CO2 IS the key -

http://www.agu.org/meetings/fm09/lectures/lecture_videos/A23A.shtml

Listen to the last question.

[depakid]

21. I'm aware of that- I was responding to the ridicuous statement re: feedback loops

i.e. methane, etc.

[tabatha]

22. Yep, it is reasonably clear when the science is not understood.

[Name removed]

24. Deleted message

Message removed by moderator. Click here to review the message board rules.

[bhikkhu]

27. Humans dump 29 billion tons of CO2 into the atmosphere per year.

No devastating feedback loop is needed to account for the measured increases.

[Name removed]

29. Deleted message

Message removed by moderator. Click here to review the message board rules.

[bhikkhu]

30. I haven't heard any predictions of rapid acceleration

What I have heard is regarding the fraction of anthropogenic CO2 remaining in the atmosphere that the OP talks about. It's been fairly stable, as in for every 100 million tons we add to the atmosphere, about 45 million tons stay in the atmosphere. The rest is absorbed, concentrating in the oceans and plant tissues. What I had read earlier in the year was that there were indications this may have hit a limit - as in, of the last 100 million tons added to the atmosphere, 50 million tons were still there (which is a change from the linear trend, but hardly a rapid acceleration). Of course, there's no such immediate and accurate accounting for the whereabouts of any given CO2 particles, but the sense of the OP article, to me, addresses the question of whether we had reached a point of acceleration in atmospheric CO2 levels. The OP indicates a negative there, which is fine - no acceleration at present; a continuation of current trends.

As to whether I agree something is nonsense, I don't know what you wish me to agree to. I haven't read of accelerating CO2 levels anywhere except as speculation, they aren't exactly necessary in any way to arrive at dire predictions, and I don't assume that they were an essentially erroneous part of any of the computer modeling. The linear increase we have is quite bad enough, and the models predicting its effects have been refined and re-worked and gone over with fine toothed combs many many times over the past thirty years or so employing every new piece of data to further improve and correct the models to reflect and predict the real world effectively.

[guardian]

17. Yes but

Doomers usually have a pretty dim grasp of reality.

Not much difference between the AGW Doomers and the the people who lived underground in the movie “Beneath the Planet of the Apes,” the ones who worshipped the nuclear missile. Both worship doomsday (as long as it is "peer reviewed" by fellow Doomers.)

[jpak]

18. Yes the Mauna Loa data and all the ice core data are wrong wrong wrong!!!111

All the direct measurements are wrong!!!111

and here is no Suess Effect!!1111

:rofl:

http://www.globalwarmingart.com/images/archive/8/88/20090204035230!Mauna_Loa_Carbon_Dioxide.png

[tabatha]

19. You misread it and misunderstood it.

When CO2 is released into the atmosphere, some of it is absorbed back by plants and the ocean.
45% does not - it remains airborne.
The fraction - 45% - has not changed.

However, the quantity has changed - i.e. why the total amount (not fraction) has increased.

See #7

"So, if we emitted 1 billion tonnes of CO2 in 1 year, 450 million tonnes stayed in the atmosphere. Many years later, when we emitted 10 billion tonnes, 4,500 million tonnes stayed in the atmosphere. And the same proportion is still getting added to the CO2 in the atmosphere each year now. That's all this is saying."

[joshcryer]

23. The fifth comment on RC about this nails it:

http://www.realclimate.org/index.php/archives/2010/01/unforced-variations-2/#comments

Heraclitus says:
1 January 2010 at 12:30 PM

I was initially disappointed by the misleading headline on the Knorr article on ScienceDaily, but I think this is going to turn out to be an excellent opportunity to expose the idiocy of the deniers. Not, of course, that they have any shame.

[CHIMO]

28. Just

The old Henry's law in real life.

http://en.wikipedia.org/wiki/Henry's_law

Throw in some ionic interactions and precipitation of carbonates in the water and you have a real life chemistry problem.

In a few million years it may all be examined. But not by us.