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Thursday, October 17, 2013

CO2 is plant food? Not on your nellie, sez Anthony (Pavlov) Watts and his dogs!

Sou | 10:06 AM Go to the first of 9 comments. Add a comment

Did anyone say deniers are nuts?  Here is a paper not just telling everyone that plants are using a heap more CO2, but quantifying just how much more CO2 has been absorbed.

How does Anthony Watts react?  After all his articles about how "CO2 is plant food", you'd think he'd be shouting from the rooftops that at last those wretched scientists started listening to science deniers, wouldn't you.

But no! He's posted the press release under the headline:

Climate Craziness of the Week: Plants blamed for us not roasting since 1950

Perhaps Anthony didn't like the way the conclusion was worded, although it's on the cards that he hasn't read the paper itself.  He probably just skimmed the press release he copied and pasted.  This call to arms from Anthony Watts is archived here.

Anyway, this is what Elena Shevliakova and her team found:
The results of our study indicate that historical enhanced vegetation growth has avoided release of 251–274 GtC, about an additional 85 ppm of atmospheric CO2 concentration, and a warming of 0.31 ± 0.06 °C. To accurately predict observed trends in both temperature and the atmospheric CO2 concentration over the 20th century, ESMs need to account for the interaction of LUC and enhanced vegetation growth, including vegetation regrowth on the secondary lands. CO2 fertilization is a plausible but debated mechanism for the ongoing land carbon sink. The empirical evidence for enhanced vegetation growth under elevated CO2 remains equivocal (29–32). The model used here does not include nitrogen or phosphorus limitations on carbon uptake. Some modeling (33) and observational (34–36) studies have found that nitrogen availability has not significantly affected global carbon uptake over the 20th century, whereas others have reached the opposite conclusion (37). The magnitude and the sign of the future net land carbon flux will impact the atmospheric CO2 growth rate, climate change, and any efforts to mitigate it. Because of the importance of the land sink in reconciling atmospheric CO2 and climate records, this study adds urgency to independently test and isolate the mechanisms responsible for the growing terrestrial C sink.
So the world would most probably have been quite a bit hotter already if not for the enhanced vegetation growth. You'll notice their caution though.  "The empirical evidence for enhanced vegetation growth remains equivocal." and "The model used here does not include nitrogen or phosphorus limitations on carbon uptake."

The researchers used a coupled climate–carbon cycle model (ESM2G) and gridded land use changes from 1700 to 2005. They "conducted three types of CO2 emissions-driven experiments from 1861 to 2005: historical (EH), historical without LUC (land use change)  (EHnoLU), and historical without the CO2 fertilization effect on vegetation (EHnoFR)".

The full paper is available at PNAS for those who are interested.  It reads well.

Shevliakova, Elena, et al. "Historical warming reduced due to enhanced land carbon uptake." Proceedings of the National Academy of Sciences (2013): 201314047. doi: 10.1073/pnas.1314047110

From the WUWT comments

Because Anthony led the way deriding the research, almost all of his fans followed suit.  They are well-trained pups. Here's a selection (archived here):

JohnWho says:
October 16, 2013 at 1:23 pm
“Without plants, Earth would cook under billions of tons of additional carbon”
And who would care?
Without plants, all creatures that rely on the plants would die.
So, even if they “cooked”, who would be around to eat them?
We would not have a runaway carbon cycle without plants – the carbon cycle would quickly cease to revolve, would it not?

MattN says:
October 16, 2013 at 1:24 pm
Dumbest “what if” ever. Complete waste of money.

Bob Tisdale says who needs real science when you've got blog pseudo-science at WUWT?
October 16, 2013 at 1:26 pm
Someone wasted taxpayer dollars for this? Ridiculous!!!

JohnWho has another crack and says:
October 16, 2013 at 1:29 pm
Please, Lord, stop me from reading the above:
“The planet’s land-based carbon “sink” — or carbon-storage capacity — has kept 186 billion to 192 billion tons of carbon out of the atmosphere since the mid-20th century,…”
Uh, sure is a good thing those plants did that. Wonder if they were removing carbon from the atmosphere before the mid-20th century, too?

Bob, Missoula agrees with Bob Tisdale that science is for the literate, not the scientific illiterati at WUWT:
October 16, 2013 at 1:30 pm
Bob you said what I wanted to but without cussing.

Sparks thinks all science is a big joke and says:
October 16, 2013 at 1:32 pm
I loved it, needed a good laugh!

Philip Lee is the first person to commend the researchers for (not really) saying that "CO2 is plant food".  But he gets climate models woefully wrong when he says:
October 16, 2013 at 1:34 pm
A useful admission that CO2 is plant food that promotes plant growth (that will provide food for humans) and will limit temperature in ways not modeled by climate models.

richardscourtney isn't shy about displaying his ignorance of climate models either (he seems to think, wrongly, they are "made to fit" the past), and says:
October 16, 2013 at 1:40 pm
The report says
“A unique value of this study is that it simulates the past, for which, unlike the future, we have observations,” Saleska said. “Past observations about climate and carbon dioxide provide a test about how good the model simulation was. If it’s right about the past, we should have more confidence in its ability to predict the future.
No competent scientist would utter such nonsensical drivel.
If a model cannot emulate the past there is reason to suppose it cannot predict the future.
But an ability of a model to emulate the past does NOT of itself provide any “confidence in its ability to predict the future”. This is because there are an infinite number of ways to make a model fit the past but there is only one way the future will occur.

Bennett In Vermont shows off the Dunning Kruger Effect and says:
October 16, 2013 at 1:46 pm
If they had asked an indoor gardener they could have learned that most plants don’t even hit their maximum growth potential until the level of CO2 is above 1200 ppm. That’s when they really start to take off.
Oh well, we can’t let simple facts get in the way of a Mad Magazine style scientific paper.

Tim Collins says:
October 16, 2013 at 1:56 pm
Wow what a lot of words, and I guess salary? In order to state the bleeding obvious except for the absurd postulation that plants will have so much to eat they will stop being carbon dioxide hungry – yeah right.
Stop paying these academidiots now and make them get proper jobs.

Chad Wozniak - does Chad ever think about what he writes?  He writes almost the same lot of words no matter what article he's commenting on:
October 16, 2013 at 2:15 pm
How desperate can these people get?
Will Happer at Princeton must be just shaking his head.

Okay, that's enough.  I'm sure you get the idea.  They'll never be happy these science deniers.  Scientists quantify an effect the deniers have been bleating about incessantly and the deniers still deny.  Like Pavlov's dog trained to growl whenever they come across some real science.  It doesn't matter if they agree with it or disagree.  As long as it's science they'll growl, mock, complain, tell the scientists how wrong they are and wail "if only they'd asked us deniers..."


  1. petition just started please consider and share

  2. Pavlovian is definitely the word for it. I think you're right that any scientist not on the denier's approved list is automatically derided, and it's a short list.

  3. Getup - National Day of Climate Action! Nov 17 in your capital city or regional centre.
    Be there or be square.

  4. When you run an anti-science blog based on reading press releases, all science must appear like it is new.

    "Climate forcing growth rates: doubling down on our Faustian bargain"
    James Hansen, Pushker Kharecha and Makiko Sato, 2013

    Hansen et al have also looked at this issue.

    "The surge of fossil fuel use, mainly coal, and rapid increases in atmopsheric carbon dioxide and nitrogen have "fertilised" the biosphere, "causing a large increase in net primary productivity of temperate and boreal forests", and hence an annual carbon drawdown of one billion tonnes a year."

  5. Sou's digests* of WUWT comments highlights something interesting, namely frequent mentions of money, salary, boodle in general. Maybe I'm wrong but it often seems there's a streak of misplaced jealousy or envy or some other brand of resentment woven through much of the disparaging commentary leveled at scientists.

    It's conspicuous that people in general are shoveling gobs of money into gas pumps, NFL logoware and myriad other involuntary purchases but these sneering commentariat save their own expressions of resentment for bystanders, people who cost them less than an iota as individuals. Weird psychology; our money bleeds so hard in so many directions but our choices of how and where to express our resentment are so strangely selective.

    *An iron constitution, I must say.

  6. I should add that deniers may not be aware that CO2 exchange in the biosphere is already accounted for in the coupled climate models. (Are deniers aware of anything to do with climate science?)

    This study is useful in that it focuses particularly on the carbon-climate interaction in the biosphere and examines in more detail how CO2 absorption is affected by changes in land use. It will help refine climate models. It also provides a basis for extending knowledge.

    1. Are deniers aware of anything to do with climate science?

      Well, they have heard of CO2 and they know what a thermometer is so they regard themselves as excellently qualified to make judgements on these matters. Apart from that, the answer seems to be a resounding "No".

    2. One can't help but get the impression from WUWT comments that the fake sceptics at WUWT despise all knowledge. They really are members of the Illiterati.

      The irony is that without scientific research, perennially puzzled Bob Tisdale and wondering Willis Eschenbach would have nothing on which to base their pseudo-science babbling. Richardscourtney would have even less of a clue (if that's possible) and Anthony Watts wouldn't have any subject matter for his science-denying blog.

      Some WUWT deniers are so deluded that they think that what little knowledge they have came from somewhere other than scientific research. How, for example, do they know about photosynthesis? How do they know that earth was warmer or cooler in the past? (Okay, a lot of them know diddly squat about the past.)

      Anthony posted an article about the sun yesterday, which shows that fake sceptics are selective about which knowledge they despise. The sun doesn't threaten the world view of climate science deniers. It's a safe topic and the comments showed that some of them (not all) were happy to accept the science. But give fake sceptics a topic that they think threatens the way they view the world around them and reason deserts them and is replaced by irrational emotion of the type seen in the article above.


    Burn. Australia needs this desperately.


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