CO2 effects on plants increases global warming

May 03, 2010
Map of globe shows percentage of predicted warming due to the direct effect of carbon dioxide on plants. Carbon dioxide warms the Earth because it is a greenhouse gas in the atmosphere, but it also causes plants to provide less evaporative cooling. A study by Long Cao and Ken Caldeira of the Carnegie Institution for Science finds that in some places (darkest orange) over 25 percent of the warming from increased atmospheric carbon dioxide is a result of decreased evaporative cooling by plants. Credit: Carnegie Institution

Trees and other plants help keep the planet cool, but rising levels of carbon dioxide in the atmosphere are turning down this global air conditioner. According to a new study by researchers at the Carnegie Institution for Science, in some regions more than a quarter of the warming from increased carbon dioxide is due to its direct impact on vegetation. This warming is in addition to carbon dioxide's better-known effect as a heat-trapping greenhouse gas. For scientists trying to predict global climate change in the coming century, the study underscores the importance of including plants in their climate models.

"Plants have a very complex and diverse influence on the ," says study co-author Ken Caldeira of Carnegie's Department of Global Ecology. "Plants take out of the atmosphere, but they also have other effects, such as changing the amount of from the land surface. It's impossible to make good climate predictions without taking all of these factors into account."

Plants give off water through tiny pores in their leaves, a process called evapotranspiration that cools the plant, just as perspiration cools our bodies. On a hot day, a tree can release tens of gallons of water into the air, acting as a natural for its surroundings. The plants absorb carbon dioxide for photosynthesis through the same pores (called stomata). But when carbon dioxide levels are high, the leaf pores shrink. This causes less water to be released, diminishing the tree's cooling power.

The warming effects of carbon dioxide as a greenhouse gas have been known for a long time, says Caldeira. But he and fellow Carnegie scientist Long Cao were concerned that it is not as widely recognized that carbon dioxide also warms our planet by its direct effects on plants. Previous work by Carnegie's Chris Field and Joe Berry had indicated that the effects were important. "There is no longer any doubt that carbon dioxide decreases evaporative cooling by plants and that this decreased cooling adds to global warming," says Cao. "This effect would cause significant warming even if carbon dioxide were not a ."

In their model, the researchers doubled the concentration of atmospheric carbon dioxide and recorded the magnitude and geographic pattern of warming from different factors. They found that, averaged over the entire globe, the evapotranspiration effects of plants account for 16% of warming of the land surface, with greenhouse effects accounting for the rest. But in some regions, such as parts of North America and eastern Asia, it can be more than 25% of the total warming. "If we think of a doubling of carbon dioxide as causing about four degrees of warming, in many places three of those degrees are coming from the effect of carbon dioxide in the atmosphere, and one is coming from the direct effect of carbon dioxide on plants."

The researchers also found that their model predicted that high carbon dioxide will increase the runoff from the land surface in most areas, because more water from precipitation bypasses the plant cooling system and flows directly to rivers and streams. Earlier models based on greenhouse effects of carbon dioxide had also predicted higher runoff, but the new research predicts that changes in evapotranspiration due to high carbon dioxide could have an even stronger impact on water resources than those models predict.

"These results really show that how plants respond to carbon dioxide is very important for making good climate predictions," says Caldeira. "So if we want to improve climate predictions, we need to improve the representation of land plants in the . More broadly, it shows that the kind of vegetation that's on the surface of our planet and what that vegetation is doing is very important in determining our climate. We need to take great care in considering what kind of changes we make to forests and other ecosystems, because they are likely to have important climate consequences."

The study is published in the May 3-7 online edition of the Proceedings of the National Academy of Sciences.

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Skepticus_Rex
2.4 / 5 (22) May 03, 2010
"If we think of a doubling of carbon dioxide as causing about four degrees of warming, in many places three of those degrees are coming from the effect of carbon dioxide in the atmosphere, and one is coming from the direct effect of carbon dioxide on plants."


This alone tells me that this study is a load of crapola based upon the IPCC's exaggeration factors, which in turn are based on a flawed version of the basic earth science CO2 jar experiment. In addition, there is a huge amount of model-monkeying--and we know where that has led thus far. How soon we forget the many failed predictions in the models.

In order to get a two degree increase there must be more than 15,000 ppmv CO2 in a container. It is highly unlikely that there will ever be that much CO2 in the atmosphere of earth again--barring massive volcanism, that is.

In such a case we will not have to worry about heating the environment. Many forms of life simply will suffocate and die. :)
PinkElephant
2.8 / 5 (12) May 04, 2010
Gave you a '1', since you deliberately confuse an actual greenhouse, vs. the greenhouse effect. The mechanisms involved are radically different, and your jar concept is a red herring. But then, you already knew that. If I could have given you a -5, I would have...
Titto
2.5 / 5 (13) May 04, 2010
Global Warming does not exist.
For those who are still confused, do some research and you will actually find the earth's temperature has been dropping?
thermodynamics
2.7 / 5 (15) May 04, 2010
Titto: Are you aware that March is the warmest on record and the January, February, March quarter is the 4th warmest on record? This past decade has been the warmest on record. Where do you get the information that the earth is cooling? Here is a reference. Show me yours please.

http://www.ncdc.n...t+Report

It is really not hard to find good information if you look for it. Please don't send me to Rush Limbaugh's web site for climate data (if that is where you are getting your ideas.
Egnite
2.4 / 5 (8) May 04, 2010
Is physorg the only news site that's keeping this debate active? The only thing GW is guilty of is boring readers to death, oh and creating the need for more taxes ofc, without those we'd be doomed...
CarolinaScotsman
2.9 / 5 (9) May 04, 2010
I'd say that geographic areas that have a consistantly high humidity receive very little cooling from plant evaporation. The cooling mechanism breaks down at high humidity because the water does not readily evaporate.
Arkaleus
1.9 / 5 (16) May 04, 2010
Thermodynamics,

It's good to hear the servants of Gaia preach the green word with all vigor. Not only is it the warmest day on record, it's also the greenest day. It's green because it's raining money!

Through the modern magic of religio-psuedoscience I can transmute the panic of illiterates into internationally recognized monetary units! I can actually BUY good weather with paper currency!

Obviously, the science is irrelevant! The real question is "How can I get in on the weather brokering business?"

Way to go 21st century enterprise for attempting to add "State Coercion" to the list of viable business models for sustainable dividends!

And if the big seats at the top of the green mystery pyramid are full, there's plenty more to be made in the enforcement business making sure consumers pay all their carbon protection money to the banks.

Let us sing the praises of green salvation, until we are all swept up into a carbon rapture riding electric Segways!
lengould100
3.6 / 5 (12) May 04, 2010
You call those who accept the science of AGW "illiterates", then go on a right-wing rant worthy of Cheney Himself? Wow!
Skepticus_Rex
1.5 / 5 (15) May 04, 2010
Gave you a '1', since you deliberately confuse an actual greenhouse, vs. the greenhouse effect. The mechanisms involved are radically different, and your jar concept is a red herring. But then, you already knew that. If I could have given you a -5, I would have...


Gave you an 'F' for misunderstanding my post--as usual... Gave you a '1' and would have given you a 1.0x10^-20 if it were possible... yada, yada, yada...

Seriously, though, the model-monkeying in the study is crap. The foundational argument is based on crap regurgitated via the IPCC without fact-checking.

In addition, one can get very expensive 'jars' that do not trap IR the same way a greenhouse can.

One can also set up proper controls that allow the removal of any 'noise' from the temperature sampling that would be caused by doing a correct version of the jar experiment. That you repeatedly demonstrate complete lack of understanding on the matter speaks volumes.
Skepticus_Rex
1.5 / 5 (15) May 04, 2010
There is one other thing to be said. Many of those who are most opposed to the corrected 'jar experiments' are those who know that they will not show the results desired. Many of them know full well that jars filled with CO2 will produce around a 2 degree increase in temperature over one with less or no CO2. Trouble with their situation is that earth's atmosphere will never and can never be filled with enough anthropogenic CO2 to do what can be seen in the simplistic basic earth science version of the experiment.

Many also know that lesser amounts of CO2 in the jars will not give that much of an increase and so seek to discredit any version of the experiment--even though AGW advocates themselves have in the past used the very same format of experiment (without controls) to proclaim the radiative forcing power of CO2!

Caveat Emptor! The AGW advocates are trying to sell the public something... :)
JayK
May 04, 2010
This comment has been removed by a moderator.
JayK
2.4 / 5 (7) May 04, 2010
By the way, Dachy, I'm still waiting for that apology. Maybe you can fit it in between jar-jar battles?
Skepticus_Rex
1.5 / 5 (15) May 04, 2010
Answer the questions asked you and your sockpuppets and maybe, just maybe, one might be forthcoming...pending the outcome of investigation, of course. :)

By the way, here is another quesiton for you not to answer. What need for citation? Surely you can do the simple research for yourself. It is obvious that you are too young to remember the jarred CO2 experiments taught in Basic Earth Science decades ago.

Apparently science programs in your public schools were among the first things to be cut due to budget shortfalls. :)
Skepticus_Rex
1.5 / 5 (15) May 04, 2010
Here is one version of a jar experiment which uses the glass walls and lid of the jar as a substitute for CO2:

http://www.starho...ar-7.pdf

Here is one that makes reference to this above experiment and makes suggestions for taking it further using two jars; one with CO2 and one without:

http://www.fi.edu...h-5.html

Here is the official NOAA website with their variation of the above experiment:

http://www.srh.no..._gas.htm

That took all of about--what?--a few seconds? How clueless and inept can one get?!?

By the way, were you aware that the NOAA experiment has been revised from the original one that failed and gave results the opposite of those expected on live television? Are you aware that the bottle filled with CO2 from the seltzer tablet are many, many times higher than ever will be in the earth's atmosphere as a result of man's burning of fossil fuels? Thought not... :)
PinkElephant
3.7 / 5 (9) May 04, 2010
@Skepticus_Rex,

I could've sworn we've discussed this jar nonsense before. But maybe I'm confusing you with another troll... Anyway, please spare us all any further displays of sheer ignorance and doochebaggery, go here and learn the difference between your misconceptions, and actual science:

http://en.wikiped...enhouses

And for future reference, for your own sake try not to bloviate regarding something, the very basics of which you never even bothered to learn or comprehend.
Skepticus_Rex
1.5 / 5 (15) May 04, 2010
Wikipedia?!? Um, sure... :)

Perhaps you might want to castigate a whole variety of people for performing jar and bottle experiments. The truth, however, is that you fail to understand the argument. I have also made it clear elsewhere that in no way to I equate anything of the sort of which you lay at my door. This is a sure sign of your failure to grasp the subject matter and projection your own failings upon someone else.
freethinking
1.7 / 5 (12) May 04, 2010
pink and jay you guys are predictable. If the person doesnt agree with your radical unscientific progressive thoughts and ideas, you like every other radical progressives will do the following almost in the same order every time. It all starts with ridicule, if they keep speaking then you try and ignore them, if people start listening then try to shout down the person. If it wasnt for the internet the next progression for you guys would be physical attacking the person.
PinkElephant
2.7 / 5 (7) May 04, 2010
@freethinking,

Uhhuh. Now, I'd like to assume that unlike the king of asshats, you actually viewed the short paragraph of text under the link provided, before spewing forth more useless political bile? But much as I'd like to assume as much, I know better...
Skepticus_Rex
1.6 / 5 (14) May 04, 2010
No, actually freethinking is right on the matter. When the going gets tough the AGW-faithers get rough. They spit vitriol. They try to get people fired. They try to get funding pulled. They hide the declines. They fudge data and/or otherwise make it disappear. They destroy evidence. There is little that they will not do to silence their critics.

PE's antics are enough to show that he does not understand the concepts of controlled experiments or the basics of compensating for background noise in experimentation.

He also has failed to acknowledge the fact that there are many in the scientific community who in fact do jar and bottle experiments--many of them on their own side of the AGW question. Such experimentation is fine unless it conflicts with their expected results. That is the underlying truth.

Then, they get nasty and work to discredit the same kinds of experiments they originally supported and encouraged in order to indoctrinate the masses. They also muddle the waters.
Azpod
2 / 5 (9) May 04, 2010
So plants effectively getting a fever will warm the entire planet?! Color me extremely skeptical. Even if it's true, I expect their conclusions on the total contribution to the planet's warming to be wildly inaccurate, just because virtually every other GW prediction has been wildly inaccurate.

Do I believe the planet is warming? Yes. Do I believe there's a man-made element to it? Yes. But with recent revelations of widespread data fudging, I view claims of any given decade, year or month being the warmest ever with extreme skepticism. I disregard predictions of doom because they're no more likely to be true than past predictions of doom, and I oppose any attempt to spend hundreds of billions of dollars to prevent something that will have little, if any, real impact on the majority of civilization.

The positive effects of global warming are being completely ignored by the alarmists and the media alike. For all we know, global warming could be good thing!
JayK
3 / 5 (6) May 04, 2010
Wow, those aren't citations, dacharpyass. Not even remotely close. I don't blame you for going back to junior high school science texts, it's probably about as far as you ever went with your education.

And I don't answer your direct questions, I just liek to ridicule your inane attempts at disparaging real science.
Skepticus_Rex
1.4 / 5 (10) May 05, 2010
Wow, those aren't citations, dacharpyass. Not even remotely close. I don't blame you for going back to junior high school science texts, it's probably about as far as you ever went with your education.


Actually, they were for your benefit and on your level since it is obvious that you do not understand the science itself.

And I don't answer your direct questions, I just liek to ridicule your inane attempts at disparaging real science.


Because you can't answer the questions in some cases, but do not want to have to answer them in others due to what you will reveal about yourself should you do so. Understood... :)
Skepticus_Rex
1.4 / 5 (10) May 05, 2010
Oh, by the way, JayK et al., thanks for admitting to being an internet troll. That was rather big of you to do so. :)
PinkElephant
3.7 / 5 (6) May 05, 2010
Ok, troll. Since you won't be bothered to follow one simple link, I'll go marjon on you and quote the thing. Go ahead and pretend to ignore THIS:
The "greenhouse effect" is named by analogy to greenhouses but this is a misnomer. The greenhouse effect and a real greenhouse are similar in that they both limit the rate of thermal energy flowing out of the system, but the mechanisms by which heat is retained are different. A greenhouse works primarily by preventing absorbed heat from leaving the structure through convection, i.e. sensible heat transport. The greenhouse effect heats the earth because greenhouse gases absorb outgoing radiative energy and re-emit some of it back towards earth.

A greenhouse is built of any material that passes sunlight, usually glass, or plastic. It mainly heats up because the sun warms the ground inside, which then warms the air in the greenhouse.
PinkElephant
3.7 / 5 (6) May 05, 2010
(continued)
The air continues to heat because it is confined within the greenhouse, unlike the environment outside the greenhouse where warm air near the surface rises and mixes with cooler air aloft. This can be demonstrated by opening a small window near the roof of a greenhouse: the temperature will drop considerably. It has also been demonstrated experimentally (R. W. Wood, 1909) that a "greenhouse" with a cover of rock salt (which is transparent to infra red) heats up an enclosure similarly to one with a glass cover.[24] Thus greenhouses work primarily by preventing convective cooling.[25][26]

In the greenhouse effect, rather than retaining (sensible) heat by physically preventing movement of the air, greenhouse gases act to warm the Earth by re-radiating some of the energy back towards the surface. This process exists in real greenhouses, but is comparatively unimportant there.
PinkElephant
3.3 / 5 (7) May 05, 2010
Now as for jars, I suggest you read the following. It is more than just a couple of paragraphs, and since you've proven incapable of reading even a couple of paragraphs, I don't hold high hopes of you reading what follows. But I'm not completely unsympathetic to the plight of idiocy, so here's yet another chance for you to actually learn:

Part 1

http://www.realcl...rgument/

Part 2

http://www.realcl...part-ii/
Skepticus_Rex
1.4 / 5 (11) May 05, 2010
PE, I am hardly a troll. Now, JayK et al., on the other hand...

Come on PE, give us something other than a blog...

People on the skeptical side get attacked and castigated for making reference to blogs even when they don't. What is as good for the goose would seem to be as good as for the gander...

And once again, I have made no claims regarding the likening of glass greenhouses to the greenhouse effect so you have most effectively wasted your time addressing me as you do.

All I have done is to point out that there are those in the AGW camp who have used and proposed such jar experiments on the AGW side of the fence and you, JayK like, have taken that and run with it in making claims for me that I have not made actually made myself.

Furthermore, are you sure you want to go down that road of using a source that bases its information on Wood's study? AGW skeptics and GW deniers alike make ready use of that study, too. It is unusual to see an AGW faither refer to it. :)
Skepticus_Rex
1.4 / 5 (11) May 05, 2010
By the way, I actually did read the blog references that you gave but these do not pertain to me or to my argumentation. I have never made use of Angstrom nor do I make arguments regarding so-called "gassy saturation" so you again wasted your time misunderstanding and referencing something that does not apply. Thanks for playing. :)
Skepticus_Rex
1.4 / 5 (11) May 05, 2010
By the way, PE, have you actually read R. W. Wood's "A Note on the Theory of the Greenhouse"? If you have, what did/do you think of the following taken from said note?

Is it therefore necessary to pay attention to trapped radiation in deducing the temperature of a planet as affected by its atmosphere? The solar rays penetrate the atmosphere, warm the ground, which in turn warms the atmosphere by contact and by convection currents. The heat received is thus stored up in the atmosphere, remaining there on account of the very low radiating power of a gas. It seems to me very doubtful if the atmosphere is warmed to any great extent by absorbing the radiation from the ground, even under the most favourable conditions.
Arkaleus
1.8 / 5 (11) May 05, 2010
I have to laugh at people who get caught up debating the esoteric minutiae of climate and geophysics.

While petty science wars are humorous, the real danger is caused by abusing the media with stories whose sole purpose is to create alarm in people unable to judge competently.

There is no need to panic and feel pressure to "act now". That is how crooked salesmen get you to sign the dotted line. You and I are the prey of sophisticated schemers who have no problem parasiting our social system with deceitful laws backed by fools who were told to panic by their televisions.

People who lack the depth of understanding to realize the design behind the green mystery machine do nothing except cloud the discussion and help break down Western integrity.

Americans have a long history of getting duped by charlatans and quacks, and Europeans have the constant threat of totalitarian powers trying to edge their parties into ruling positions.

Their corruption is trying to go global.
Skepticus_Rex
1 / 5 (8) May 05, 2010
Heheh! Here is the NASA version of the "jar" experiment or, as in their variation, "pop-bottle" experiment for the kiddies to try.

http://glory.gsfc...ent.html

This one, of course, lacks more detailed and varied controls.
JayK
3 / 5 (4) May 05, 2010
Do you have any idea what else it lacks?
PinkElephant
3.7 / 5 (6) May 05, 2010
And once again, I have made no claims regarding the likening of glass greenhouses to the greenhouse effect
Your words or not, troll:
In order to get a two degree increase there must be more than 15,000 ppmv CO2 in a container.
And as for this
I actually did read the blog references that you gave but these do not pertain to me or to my argumentation.
They have EVERYTHING to do with your "argumentation". They explain the true nature and mechanism of the atmospheric greenhouse effect. If you really did read through, then you ought to finally understand something about the topic, and shut up about glass jars. But since you haven't, then obviously you didn't. You're both a troll and a liar.
Skepticus_Rex
1 / 5 (10) May 05, 2010
Do you have any idea what else it lacks?


Quite a bit. Absolutely. How about you? Never mind. You won't answer, anyway. :)
Skepticus_Rex
1.3 / 5 (12) May 05, 2010
PE,

The above is additional proof you misunderstand everything I have posted on the matter.

The two-degree increase is from observations actually done. And, it is a two-degree INCREASE OVER THE CONTROL in the simpler version involving only two jars. All of the jars will have an increase in temperature, WHICH IS WHAT THE CONTROLS ARE FOR.

I thought I would put the words you keep seeming to miss in all-caps. Deliberately missing them and misusing my posts is very trollish behavior. Are you projecting your failings onto me? :)

Your blog links have nothing to do with what I have actually said. I have said nothing about "gassy saturation" and I have made no arguments thereon or therewith.

That you keep thinking that I have and that you apply the blogs to what I have written demonstrates most clearly your lack of understanding on the subject matter. Well, there is that and your fallacious 'claims' elsewhere (hint: the thread whence quote) about the result of doubling CO2. :)
Skepticus_Rex
1.3 / 5 (12) May 05, 2010
Oh, and by the way, have neither of you trollish sorts heard of something referred to as "IR-Transparent Glass"?

There are many ways to do the experiments using differing materials in the containers (each method producing differing results and increasing in complexity) and there are more wavelengths of IR than one.

In any case it is important to have good controls so as to remove the "noise" from the results. Got a clue, yet? :)
PinkElephant
3.7 / 5 (6) May 05, 2010
So, troll... shall you finally admit that your jars -- being examples of a true greenhouse -- have absolutely NOTHING to do with the (admittedly misnamed) atmospheric greenhouse effect? Or must I quote the distinction to you, again?
Skepticus_Rex
1 / 5 (9) May 05, 2010
I have neither admitted to nor denied anything, really. You also are making considerable, troll-like assumptions, however. Nowhere, anywhere, have I ever made a direct comparison of the jar experiment and its effects on the air in the jars with the atmospheric phenomenon given the namesake. That is the assumption you are manufacturing for me and caricaturing.

But, keep on trolling and making those assumptions if you must. It is no skin off my nose that you do not understand the concept of controls and made claims like you have regarding so-called exponential increases via doubling of CO2.

By the way, you never did answer the question as to what you thought or think about Wood's above statement in his note regarding whether we really need to care about what goes on in the atmosphere, and his doubt about increases in temperatures. What say you?

Oh, one other thing: Have you told the scientists at NASA how stupid they are for recommending a jar experiment to illustrate AGW? :)
PinkElephant
3.4 / 5 (5) May 06, 2010
Nowhere, anywhere, have I ever made a direct comparison of the jar experiment and its effects on the air in the jars with the atmospheric phenomenon given the namesake.
Are these not your words, troll:
This alone tells me that this study is a load of crapola based upon the IPCC's exaggeration factors, which in turn are based on a flawed version of the basic earth science CO2 jar experiment.
Are you suffering from a multiple personality disorder, or split brain syndrome?
PinkElephant
3.4 / 5 (5) May 06, 2010
you never did answer the question as to what you thought or think about Wood's above statement in his note regarding whether we really need to care about what goes on in the atmosphere, and his doubt about increases in temperatures
Didn't I? I thought we've finally arrived, after much fatuous heaving and hawing, at the planet-shattering revelation that greenhouses have almost nothing in common with the actual atmospheric greenhouse effect. Yet you ask what I think about erroneous century-old assertions regarding the atmosphere, naively made on the basis of greenhouse experiments. That makes me think I'm mistaken: maybe the distinction between the atmosphere and greenhouses hasn't sunk in through to you yet, after all.
Have you told the scientists at NASA how stupid they are for recommending a jar experiment to illustrate AGW?
I'm sorry that, in your ignorance, you found it all so confusing. But now you've been set straight, at long last. (Oh, whom am I kidding...)
Skepticus_Rex
1 / 5 (8) May 06, 2010
Nowhere, anywhere, have I ever made a direct comparison of the jar experiment and its effects on the air in the jars with the atmospheric phenomenon given the namesake.
Are these not your words, troll:
This alone tells me that this study is a load of crapola based upon the IPCC's exaggeration factors, which in turn are based on a flawed version of the basic earth science CO2 jar experiment.
Are you suffering from a multiple personality disorder, or split brain syndrome?


The real question is, are you really so dense that you cannot understand the words in the quote? Or do you need to go to a Sylvan Learning Center to get past a reading disability? Nowhere in that quote do I do what you think I do. I'm beginning to wonder if you might not be a JayK sockpuppet, too. He has the same kind of comprehension problems.

What do you think of the Wood's statement and have you told scientists at NASA how stupid they are for proposing a jar experiment to illustrate AGW?
Skepticus_Rex
1 / 5 (9) May 06, 2010
PE, you are the one who gave a link to a Wikipedia article containing references to Wood. I asked you whether you wanted to go down that road. You did not answer so I asked you what you thought of Wood's actual statements. You seem to have missed both that and Wood's actual stance on the subject of the greenhouse.

Like JayK, you seem to be having a problem using and comprehending what you read, particularly when it comes to climate science. Not sure what the problem really is but you might want to consider getting some help with the problem. The problem is especially in a bad way since you keep attributing meanings to what I have posted that I never actually posted myself. They are your construct of my words, not my own. Do keep trying, though. I haven't laughed this hard for weeks. :)

Of course, if it keeps up, I think I will more pity you than I do.
PinkElephant
3 / 5 (4) May 06, 2010
The main point of the Wood reference was not what he thought about the atmosphere. It was about his experiment, which demonstrated that greenhouses work by preventing convention (thereby impeding sensible heat transport), rather than by preventing radiative cooling.

Wood's speculation about relevance of this finding to the atmosphere, is both erroneous and irrelevant.

But of course, far be it from a troll such as yourself, to get the point of anything that contradicts your delusional preconceptions.

As for how stupid NASA is, that's not the question here. The question here, is why don't you know enough about the greenhouse effect in the first place, so that you aren't so wildly mislead by poor analogies on NASA's part?

It's puzzling that someone should be so insistent on publicly making such an ass of himself, repeatedly. Are you a sadomasochist?
Skepticus_Rex
1 / 5 (7) May 06, 2010
I am not misled by NASA's analogy. If I were I would be an AGW faither.

As to making an ass of one's self, pot, kettle, black, my friend.
lewando
1.8 / 5 (6) May 08, 2010
Evaporative cooling will indeed cool the trees but will heat the surrounding air. It is a zero-sum energy transfer process.

If trees are emitting less water vapor (a greenhouse gas) due to increased CO2, would this not mitigate the efeect of increased CO2?
PinkElephant
5 / 5 (2) May 08, 2010
Evaporative cooling will indeed cool the trees but will heat the surrounding air.
Evaporating water is undergoing an endothermic phase transition (absorbing energy, without going up in temperature). The extra humidity will precipitate out as dew, during the cooler parts of the day/night: an exothermic phase transition, releasing energy back into surrounding air. Overall, this amounts to dammpening of night-day temperature extremes.
If trees are emitting less water vapor (a greenhouse gas) due to increased CO2, would this not mitigate the efeect of increased CO2?
A bit. The majority of CO2's greenhouse contribution occurs high in the atmosphere (upper troposphere/lower stratosphere), where water vapor content drops off sharply. Lower down, convection dominates and atmosphere is optically thick in water vapor absorption frequencies. The study reported on, indicates that the net effect is to increase surface heating (and by extension, near-surface sensible heat transport.)
kasen
1.5 / 5 (2) May 09, 2010
Plant pores get smaller in response to increased CO2, but doesn't the entire plant get bigger/grow faster too, therefore maintaining the required evapotranspiration quota?

I mean, it seems only logical that a bigger/faster expanding surface would lead to smaller pores, since the amount of soil nutrients absorbed varies slowly and therefore the amount of CO2 absorbed has to vary at an appropriate pace, so as not to "stall the engine". I'm just guessing, but roots should have smaller surface areas and grow slower than leaves.

Speaking of jars, I wonder if these people bothered to take two actual plants, stick them in jars and increase the amount of CO2 in one, while measuring the humidity in both. The ratio humidity/plant mass should stay the same.
Forestgnome
1 / 5 (2) May 09, 2010
This just proves how myopic researchers can be. This is a leaf by leaf comparison. They forgot to include that the plant growth, therefore the number of leaves, will explode in a CO2-rich atmosphere. The increase in leaf area will far outweigh the decrease in transpiration.
Djincs
1 / 5 (1) May 09, 2010
(sorry for my spelling)
this is so wrong, the wather vapour itself is a green gass, the scurge of the modern science is the falce logic, getting back CO2 is good, long ago it were in the atmosphere aniway, warming may exist but it is good for some and bad for others, ask the russians if they are afraid by it.....
PinkElephant
5 / 5 (1) May 10, 2010
@kasen, Forestgnome,

You overestimate the effectiveness of CO2 fertilization. I has been demonstrated that, while CO2-enriched air does benefit plant growth, growth is constrained by the availability of water and key nutrients in the soil. In other words, you get much more -- and more long-term sustainable -- bang for the buck by supplying (let's say) animal manure to a plant's roots, than by poring CO2 into its leaves. See here: http://www.realcl...ization/
kasen
1 / 5 (1) May 10, 2010
Several comments on that link. First off, the links to the articles concerning the actual experiments are both broken. Secondly, said experiments have apparently been done in forests.

There are two things wrong with that: uncontrolled experimental medium and big, slow growing plant-life(i.e. trees). The first is obvious, you have weather, soil, fauna to worry about, as well as maintaining a constant CO2 concentration in an open area. As for the second, I think you'd need a few decades to properly see the effects of changing one environmental factor on a tree. Also, trees are not only big, but also complex, so water and nutrient availability is much more limiting for them than for grass, for instance.

I'd honestly like to know if anyone did the plant-in-a-jar thing. Would be a nice research project.

Oh, and thirdly, these articles suggest that there's no way out whatsoever, not even planting more trees will save us from the evil CO2. "Don't plant trees, pay the government!"
JayK
1 / 5 (1) May 10, 2010
Most plants are largely carbon neutral unless they are sequestered.
PinkElephant
not rated yet May 10, 2010
@kasen,

Sorry about the broken links; I didn't check. It's been a while since those reports came out; I searched for them and the article I linked was the first that came up in results. Seemed like a nice succinct summary... Here's a longer article, directly addressing some of your concerns:

http://www.nichol...oneffect
kasen
2 / 5 (1) May 11, 2010
I've also done some googling myself and found the same info. All these FACE or chamber studies, however, are concerned with, and verify, increases in biomass production.

There is, indeed, a 1 degree temperature increase in the FACE at Duke forest, but you have to keep in mind how the experiment is set up: a patch of trees encircled by tall metallic pillars with gas dispensers. Thermal mass comes to mind, both for the pillars and the gas.

Also, from your latest link: "the more CO2 in the atmosphere, the more productive green plants are and the more CO2 they draw down". So, for JayK, plants aren't carbon neutral as long as they can grow.

I'm just saying, organisms that can live for millennia shouldn't be prone to overheating problems.
JayK
3 / 5 (2) May 11, 2010
Long term, in view of climate change, large plants are climate neutral, as they release their CO2 back unless they are sequestered. The important part is the sequestering.

If you want to look at the math for what I'm talking about, do a search on using biomass as fuel and the discussion of it being carbon neutral. Their calculations are pretty extensive (it isn't actually carbon neutral).

The only plants that tend to be carbon negative are small plants with extensive root systems, such as switchgrass. It naturally sequesters a small amount of the CO2 it takes up during its growth.
http://www.uvm.ed...in/smith et al. 2003.pdf
kasen
4 / 5 (1) May 11, 2010
they release their CO2 back unless they are sequestered


Wait, naturally or with help from us? I was referring to plants being used just as carbon sinks, not as fuel. There are all sorts of other problems with that notion anyway, beyond carbon neutrality.
PinkElephant
5 / 5 (1) May 11, 2010
Naturally, for the most part. Dead plant matter decays (is consumed by animals and microorganisms), with the end result being release of CO2 and CH4 back into the atmosphere. Dead plant matter also gets taken up by the root systems of living plants, recycling it into living plant matter. Forest/prairie fires directly convert both dead and living plant matter into CO2, CO, NO, etc. Erosion exposes buried dead plant matter (such as root systems.) Some amount of plant-locked carbon does get sequestered, when it's buried by sediments or when it settles to ocean/sea/lake bottom (effectively, another form of getting "buried by sediment".) This is a relatively slow process, and on the whole it roughly tends to balance out carbon emission by volcanoes, hot springs, natural gas leaks, etc. It will take many centuries for this natural sequestration to remove the extra anthropogenic CO2, even if we completely stop emitting today.
JayK
3.7 / 5 (3) May 11, 2010
I actually wasn't implying naturally or through anthropogenic causes, just the process that CO2 can be locked away in organic matter. There may be some new idea or process that comes along that creates a new biomass sequestering model, so I'm leaving all options open without limiting myself to current technologies. Unfortunately, right now, the carbon output of human methods of sequestration seem to greatly outweigh the benefits of the attempt.
kasen
5 / 5 (2) May 11, 2010
Dead plant matter also gets taken up by the root systems of living plants, recycling it into living plant matter.


I somehow thought this was the case for 90%+ of plant life, more so as density increases. Never really studied the matter, though, so I'll take your word on it for now.
Skeptic_Heretic
5 / 5 (1) May 12, 2010


I somehow thought this was the case for 90%+ of plant life, more so as density increases. Never really studied the matter, though, so I'll take your word on it for now.

This is the case for 100% of plants. All "soil" that wasn't formed via erosion is composed primarily of dead plants and animals from the first invasion of land by life. For a long time odd looking trees with very simple but penetrating root systems (and it's a stretch to call them systems) permeated the landscape along with the various fungi and lichens of the time. It wasn't until this material began to break down that we had topsoil of any appreciable quantity by which our current plant life could derive nutrition.

FYI: the majority of carbon sequestered by plants is done in the ocean, not on land.
Skepticus_Rex
1.8 / 5 (8) May 14, 2010
FYI: the majority of carbon sequestered by plants is done in the ocean, not on land.


This is quite correct. The majority of oxygen on the planet also comes as a result of ocean plants. This is why we must spend more and expend more effort to protect the oceans from our chemical pollution and agricultural run-off rather than overly concerning ourselves with atmospheric CO2 in the face of unsettled scientific questions.
Skepticus_Rex
1 / 5 (6) May 15, 2010
...
It will take many centuries for this natural sequestration to remove the extra anthropogenic CO2, even if we completely stop emitting today.


That is not certain at all. There are many uncertainties in the equations and new information pours in all the time. While I disagree with a few points in the following link, I think it a worthwhile summary to read.

http://www.gcrio....-7-1.pdf

The summary article concludes concerning CO2, as of this post, as follows:
Were it not for the natural sinks taking up nearly half the human-produced CO2 over the past 15 years, atmospheric concentrations would have grown even more dramatically.


So, if it took 15 years to remove nearly half the anthropogenic emissions under full and increasing emissions, what really would happen if we stopped emitting completely?

In any case, claiming "many centuries" to clear anthropogenic CO2 has more the appearance of being an IPCC-based exaggeration factor.