Climatists not Fair Dinkum?
To the Editor
Climate Conversation
27th August 2012
A “greenhouse gas” is one capable of absorbing infra-red (IR) radiation.
The most common atmospheric gases with such properties are water vapour and carbon dioxide (CO2). Water vapour is far more abundant with an average of 20,000 parts-per-million (ppm) in the atmosphere compared to just 395 ppm of CO2. Moreover water vapour is more effective as a greenhouse gas because it can absorb IR radiation over far more bands of the IR spectrum.
Therefore, if man-made CO2 causes dangerous global warming, (a dubious proposition anyway), then man-made water vapour is far more dangerous.
The two main electricity generation fuels in Australia are coal and gas. Coal is a dense fuel with a high carbon content which, when burnt, produces mainly CO2 with some water vapour. Natural gas has more hydrogen and less carbon and produces a higher proportion of water vapour, the main greenhouse gas.
Thus if the climate alarmists are really scared of man-made greenhouse gases, they should be promoting coal instead of gas or systems that need 100% gas backup, such as wind.
And if they believe a tax on man-made greenhouse gases will control the climate, a tax on steam makes more sense than a tax on carbon dioxide.
Finally, if they want “zero emissions” of either greenhouse gas, the only significant energy sources that qualify are nuclear, hydro and geothermal.
Maybe the climatists are not fair dinkum?
Viv Forbes
Rosewood,
Queensland,
Australia.
forbes [at] carbon-sense [dot] com
Views: 490
The atmosphere can only absorb a finite amount of water vapour which is a function of air temperature. There is much more dynamic interchange between the atmosphere and the surface for water vapour than the other greenhouse gases. If extra water vapour is added to the atmosphere, it condenses and falls as rain or snow within a week or two.
I thought water vapour was the entire basis of the (C)AGW hypothesis – warming from CO2 causes more water vapour to reside in the atmosphere, thereby amplifying the initial warming of CO2
Simon,
You seem to be saying that the greenhouse effect of the wv lasts for only a short time, but that is not so. It is always present. Water vapour (wv) forms part of the hydrological cycle and your comment applies to all wv, not just “extra” wv. Being a continuous process, the atmosphere always contains about 2% or 3% wv. So, even while it precipitates out of the atmosphere, the greenhouse effect of the wv is more or less maintained.
Why do you mention there’s a limit to the wv in the atmosphere? At a mere 4% maximum it’s surely nowhere near what’s possible. The IPCC mentions no limit, but they do say there’s no upper limit to the global temperature increase they predict.
What do you mean by a “more dynamic interchange” for wv?
So, even while it precipitates out of the atmosphere, the greenhouse effect of the wv is more or less maintained
Yup… water vapour concentration is mainly down to atmospheric temperature, and anything added soon falls out unless the world gets warmer.
Strictly speaking, atmospheric wv increases only if temperature rises and anything added soon falls out if the temperature falls. I guess we all want to know precisely how much the temperature goes up on a given increase in wv. Also, crucially, whether the net effect of the increased wv is warming, or whether, as shown clearly in the tropics, cooling.
… so you’ll be taking this post down?
What?! Why?
Because what you just said shows why human water vapour emissions are not a problem
I never imagined that they were a problem.
On the other hand, the letter-writer said only: “if man-made CO2 causes dangerous global warming, (a dubious proposition anyway), then man-made water vapour is far more dangerous.” But man-made CO2 emissions don’t cause dangerous global warming.
Also, I would qualify his statement, something like: “… then, kg for kg, man-made wv is far more dangerous.” Because I’ve no idea how the quantities of CO2 and wv compare, and if we don’t emit much wv it cannot be dangerous, no matter how dangerous it could be, if you see what I mean.
In any case, I wouldn’t take down a reader’s letter unless it was offensive. In which case I wouldn’t have put it up in the first place. 🙂
…right, but water vapour falls out of the atmosphere (as you say) and CO2 doesn’t.
So you’ll only pull a post if it’s offensive, not if it’s stupid?
David Winter, are you the local internet policeman who determines whether a blog post should be taken down or not?
if so, can I see your ID please?
David, good question. Do I consider your statement “CO2 doesn’t [leave the atmosphere]” as other than stupid, knowing that hundreds of gigatonnes of CO2 enter and leave the atmosphere each year? If I don’t, will I take it down? Or will I, as I usually do, let it stand as a legitimate contribution to the conversation?
Everyone’s free to express their opinion here, David. Why should I censor them? The standards of Skeptical Science or Real Climate don’t apply to us because we’re not afraid of contrary opinions. Before I had reasons to doubt CAGW claims, I had no doubt that free discussions were the more fruitful. The only standard is to try to maintain the climate of freedom, which emotional and ad hominem remarks can spoil.
The hostile remarks might be deleted, but not the stupid ones, for they teach us all.
Thanks for the question!
Richard, if you don’t know the difference between flux in CO2 and the net effect of added CO2 then I don’t know where to start.
It’s your blog, and you can do what you want. I’m just a little surprised that you’d run a post that is so stupid.
Maybe a post, even if the premise is wrong, might actually provoke some thought.
After all, it might be more interesting than writing a screed that drones on about “deniers”, not mentioning any names but some SciBlogs spring to mind.
That’s a good point, David; I was talking about the total flux and forgot the anthro increment; I do understand the difference. Simon’s original comment applied only to the “extra” water vapour but I pointed out it’s true for the total wv. The same with CO2 – it’s a big cycle, and total amounts of both substances vary over several time scales. There’s no doubt that water vapour is far more powerful than CO2 in its “greenhouse” effect, though plenty of people give the impression that the reverse is true. You only need to know the mass of each substance in the atmosphere to understand that – about 3000 gigatonnes of CO2 against 13,000 gigatonnes of water vapour. Without considering the greater influence of H2O across the spectrum.
That’s the point that Viv Forbes was making, in somewhat provocative style.
Your intolerance of a letter that’s sparked a bit of discussion and makes some interesting points other than about water vapour is a separate matter and is impertinent in a discussion. Would you sometimes explain something where it was misunderstood, rather than insult the intelligence? What would cause you to do that? Does a person’s attitude towards the topic make you intolerant?
Finally, what, really, is stupid about the letter? Do you know the magnitude of the climate forcing caused by human emissions of water vapour that you dismiss it so readily?
“….then man-made water vapour is far more dangerous”
That is only if there actually is a positive WV feedback against temperature that climate science has assumed.
Carl Brehmer shows in the paper linked below, that by empirical observations along with an excellent positive/negative, ascending/descending feedback tutorial that the presence of humidity is clearly a negative feedback against temperature:-
The Greenhouse Effect . . . Explored Is “Water Vapor Feedback” Positive or Negative?
Carl Brehmer, © February 21, 2012
http://myweb.cableone.net/carlallen/Greenhouse_Effect_Research/Water%20Feedback_files/Is%20Water%20Vapor%20Feedback%20Positive%20or%20Negative.pdf
And all of the industrialization and irrigation across USA hasn’t had an adverse effect on US specific humidity either:-
Trends in U.S. surface humidity, 1930 – 2010.
Paula J. Brown
Arthur T. DeGaetano
2012
http://hockeyschtick.blogspot.co.nz/2012/08/new-paper-finds-no-evidence-of.html
“Average long-term trends (1930 – 2010) indicate that temperature has warmed, but little change has occurred in dewpoint and specific humidity”
US CO2 must be the weaker type if it hasn’t induced the 3x WV amplification that climate science also assumes.
A sample from Carl’s “paper”:
The four sets of cities that I used for my comparative study between “arid” and
“humid” climates were: Phoenix vs. Dallas, Las Vegas vs. Knoxville, Death Valley vs.
Huntsville, Riyadh, Saudi Arabia vs. Bogra, Bangladesh. In all four cases the more
humid climate had a significantly cooler yearly mean temperature than the arid climate.
Yes Simon, you’ve got the gist of it.
“In all four cases the more humid climate had a significantly cooler yearly mean temperature than the arid climate”
That’s how a negative humidity feedback against ascending temperature works.
Conversely, the negative humidity feedback against descending temperature constrains the humid climate from cooling at night to the extent that an arid climate does.
Basically just what most folks know intuitively but climate science doesn’t.
No, it shows that some folks intuition is biased by their world view. Cherry-picking and comparing unrelated sites is not valid. To extrapolate the example to a ridiculous level, the driest place in the world is the Dry Valleys of Antarctica where precipitation is impossible. The wettest place in the world is allegedly Mawsynram in India. India is warmer than Antarctica, so by your logic I have “proved” that more a humid climate has a significantly warmer yearly mean temperature.
“….the driest place in the world is the Dry Valleys of Antarctica where precipitation is impossible”
And what is the temperature? This is an example of zero feedback from humidity against descending temperature.
“….comparing unrelated sites is not valid”
You didn’t read Carl’s methodology very well did you Simon? He explicitly compares locations on similar latitude and therefore the sites are very much related and the comparisons valid.
“To extrapolate the example to a ridiculous level”
“The wettest place in the world is allegedly Mawsynram in India. India is warmer than Antarctica, so by your logic I have “proved” that more a humid climate has a significantly warmer yearly mean temperature”
So Simon, you’ve misunderstood the logic and method of Carl Brehmer’s paper to the “ridiculous level” of placing Antarctica on the same latitude as India in terms of Brehmer’s method.
I suggest that you read the Brehmer paper again Simon. This time slowly and carefully.
It’s not valid to compare sites at the same latitude either. The localised climate effects that makes site A more humid than site B also affect temperature. Brehmer’s contention is that the addition of water to a climate system causes a perceptible drop in the yearly mean temperature. It would not be difficult to find examples where the inverse is true. As you pointed out, there is a negative humidity feedback against descending temperature.
That would be like the seven station series then?
“The localised climate effects that makes site A more humid than site B also affect temperature”
What “localised climate effects”? Presence or absence of humidity IS a localized climate effect and a feedback against the initial process.
Temperature is the initial process in the feedback system. If temperature is ascending, a negative feedback inhibits further rise and a positive feedback extends the rise further. If temperature is descending, a negative feedback inhibits further fall and a positive feedback extends the fall even further. This is why locations that lack humidity experience extremes of temperature that humid locations don’t because there is no modulation in the feedback system.
“Brehmer’s contention is that the addition of water to a climate system causes a perceptible drop in the yearly mean temperature”
It’s not a “contention” Simon, it’s an observed fact. And not only are maximums inhibited but minimums also (nights are warmer in humid locations), so the negative humidity feedback modulates both maximum and minimum temperatures.
“It would not be difficult to find examples where the inverse is true”
The inverse is “the [subtraction] of water [from] a climate system causes a perceptible [rise] in the yearly mean temperature”. This is EXACTLY the illustration of the effect of the negative humidity feedback. When humidity is present, maximum temperature is inhibited, but when humidity is absent, temperature rises higher.
What is difficult to find Simon, is very high maximum temperatures in humid locations. On the other hand, very high maximum temperatures (around 50 C) in arid locations of comparable latitude are common.
“As you pointed out, there is a negative humidity feedback against descending temperature”
The negative humidity feedback against descending temperature inhibits the fall so that minimums are higher in humid locations than are the much colder minimums of arid locations on comparable latitude.
Just remember: “Dry Sahara – Humid Singapore” and the respective Max/Min temperatures.
What you say is correct and I’m not disagreeing with you. I was talking means not maximums.
My point is that directly comparing sites at the same latitude is not valid. Altitude is also really important. So is localised weather patterns (e.g. monsoon effects) and the impact of the surrounding terrain.
“…directly comparing sites at the same latitude is not valid.”
That is rubbish Simon. The foremost criteria for categorizing the planet’s biomes is latitude:-
Arctic or subarctic
Subarctic and boreal
Temperate cold
Temperate warm or sub-tropical
Tropical
The most widely used classification of biomes is related to latitude (or temperature zoning) and humidity, but humidity distinguishes between different biomes on the same latitude so obviously there’s an opportunity to make valid scientific comparisons as Brehmer has done.
I think I will remain “intolerant” of people who mix ignorance with certainty.
Here’s what stupid about the letter – it is centered around the claim”Therefore, if man-made CO2 causes dangerous global warming, (a dubious proposition anyway), then man-made water vapour is far more dangerous.” That’s not true.
Now, if someone just says “hey, isn’t water vapour a bigger contributor tot he greenhouse effect, why aren’t scientists worried about that vapour then?” I’m more than happy to provide an explanation about residency and all of that. But you letter writer hasn’t stopped to actually learn anything about climate, rather, she’s gone from an observation about the relative forcing of some gases to the idea that climate scientists are being dodgy (not “fair dinkum”) about human contributions to the greenhouse effect. That’s pretty stupid.
You remain “intolerent”
Good, you will fit well into the SciBlogs network then
Well, yes, just as you predicted, your intolerance continues, for neither ignorance nor certainty are evidence of stupidity. Saying so just highlights your irritation.
In justifying your accusation of stupidity you do no more than disagree with the writer (who is a man, incidentally) and complain that if he should reword his comments THEN you’ll explain his error. Tosh and tush, sir! Explain anyway, if you can. This is a simple, civilised conversation. What are you expecting – PhD’s only? Nobody’s insulting YOU, as far as I see.
I think “residency” is just a complex concept to obscure the simple fact that the radiative effect of any atmospheric gas is an instantaneous process correlated to the total amount of that gas, and not in the slightest related to how long each molecule might have been present. Like the thickness of a pane of coloured glass. Why we persist in guessing the 100-year (or 50-year) effect of a greenhouse gas I don’t know, unless it’s to frighten the ignorant populace a little more.
It seems that strong believers in CAGW consistently expect “sceptics” to have studied an advanced level of climate science, and if they haven’t, it’s not the believer’s place to educate them. That just makes it so easy to say “you’re wrong, go and find out why.”
You say the writer is stupid, yet his logic is infallible. Given the one, it’s likely that scientists aren’t being honest. How else could it work?
And his ignorance deserves correction, don’t you think?
I think being certain and wrong is stupid, don’t you?
This is pretty simple (and I though you agreed?) when you add water vapour to the atmosphere is soon falls out. When you add carbon dioxide to the air it hangs around – there’s is a lot of flux, but that’s swapping one molecule for another, the net effect of carbon dioxide to the air today will be in increase in concentration for on the order of 500 years. The effect of any atmospheric gas may be instanenous, but it will continue have that effect for hundreds of years (which is why global warming potentials are calculated over large time scales).
This is not a difficult concept, or one that is particularly obscure. I can only imagine that Viv Forbes (who I now find is one of these people that think cattle are carbon neutral!) is so sure that the scientists are up to something that he didn’t bother to research the claims he made.
Reference please?
Here’s one
Model results don’t count. Here is a graphical summary of the actual observed results from decades of peer-reviewed research.
For example:
Craig (1957)
Note the use of actual observational research, something the IPCC cronies have never quite got the hang of.
David,
Are you certain that Viv Forbes is stupid? Because if you’re wrong…
I prefer to give people the benefit of the doubt. First, inform them of where they went wrong, then, if their response is to offer abuse, yes, it might confirm their stupidity. Have you got it yet? How much do we know about strangers?
In the meantime, what can you say about the relative warming of our water vapour and CO2 emissions? Yes, I know they persist for different lengths of time, but while they persist, how do they warm the atmosphere?
135 gigatonnes of CO2 is exchanged annually between atmosphere and oceans/biosphere, completely dwarfing the 6 or so gigatonnes emitted by humans.
The fact is there is NO observational physical basis for a CO2 residence time longer than about ten years.
So in fact CO2 is similar to water vapour in that regard – any perturbation equilibrates out in a relatively short time, between four and ten years.
Bob, that’s residency time not lifetime. As I’ve said, there’s plenty of flux but that’s not the relevant thing to measure.
Richard – Water vapur explains more of the greenhouse effect today than CO2 does. But we are interested in changes in the greenhouse effect, so that’s not particularly interesting.
The residency time is the lifetime, unless you can come up with a better definition of residency. The observational research gives the lifetime of CO2 in the atmosphere based on actual observed perturbations, where the atmosphere is in contact with all sources and sinks simultaneously. In other words: real life situations, not models.
And I’m quite aware of the difference between flux and residency. The annual flux value I quoted above does not represent 100% of the perturbation, merely 18%, based on a 5 year residency. As you say, the residence time, or lifetime, is the relevant measure. The peer-reviewed observational literature agrees on a lifetime of four to ten years.
Bob – the paper you cite actually has “exchange time” in it’s title – that’s the time it takes for a carbon dioxide molecule to end up in the ocean or an organism or a rock. But that’s how quickly particular carbon dioxide molecules are exchanged between one system and another – not how long extra fossil CO2 will have an effect on atmospheric concentrations of the gas.That’s what people usually mean by lifetime – it’s the lifetime impact of carbon emisions, not the life of a paricular molecule.
David,
All right, I’ll bite: why do you imply they’re not? The whole biosphere is surely carbon-neutral.
Ok. But how much warming do we get from our wv and how much from our CO2?
I don’t see the difference. When it gets into the ocean or a rock, it’s out of the atmosphere. What prolongs its life after that?
Cows, or at least their bacteria, make methane – which has a far greater warming effect than CO2 (for a shorter time).
I’m not sure that “Ok. But how much warming do we get from our wv and how much from our CO2?” is even a meaningful question – they interact with each other, espcially because of the water feedback. What we can measure is how changing concentration will change the effect – and that’s what we want to know
I don’t see the difference. When it gets into the ocean or a rock, it’s out of the atmosphere. What prolongs its life after that?
Other CO2 is going out of rocks, oceans and organisms and the same time. That’s the flux thing you’ve already agreed is important….
Cows are not carbon (or to be more precise CO2 equivalent) neutral even if you assume that grazing make pasture grow faster.
Plants absorb lots of CO2 too. The point is that the biosphere can only absorb a finite amount at a time. Any excess CO2 stays in the atmosphere. That is why the CO2 levels are rising.
Incorrect. If an amount of CO2 is added to the atmosphere, then physical molecules are added. This will increase the concentration of CO2 in the atmospere, until the extra molecules are removed. Once the extra molecules are removed, the concentration drops again. The average time taken to remove the molecules from the atmosphere (to the ocean, a tree or a rock) is the residency time.
Define for me what your “lifetime” is then, if not the time the extra CO2 molecules remain in the atmosphere.
You were happy to use the same argument for water vapour, why is it different for CO2? The only difference is the length of time taken to drop back out of the atmosphere.
David & Simon,
We could single out any similar animal, let us say giraffes and hippopotami, and accuse them of being not merely carbon-based but carbon-biased, but why bother? I mean, seriously, how much are all herbivores, including termites, raising the temperature? Remember too that trees emit methane, it’s a widespread natural phenomenon.
No – why don’t you do some research about it?
David, you’ve just fallen for the easy answer again. As I said earlier: That just makes it so easy to say “you’re wrong, go and find out why.”
If you don’t know, just say so. Otherwise please be polite and justify the argument you chose to put.
Richard you said “We could single out any similar animal, let us say giraffes and hippopotami, and accuse them of being not merely carbon-based but carbon-biased, ” without explaining how you could do that. Am i really meant to explain how each of your madly flung counterfactuals are wrong? I think I have better things to do, to be honest.
Well, you raised the matter of cows, it just doesn’t make sense to me to scoff at Viv Forbes who apparently doesn’t know about a trivial natural addition to the natural flux of CO2.
David,
It is a meaningful question to this extent, that, without knowing the magnitude of each, how can we dismiss either of them as insignificant? Why do we focus on CO2?
Richard, please read my comments and think about them for a second. I’ve answered this question about 5 times…
David,
But you were discussing the anthro increase, not the general flux. How can the increased CO2 continue in the atmosphere when it’s in a tree?
… because the tree can’t absorb any more. That’s why the additional CO2 is in the atmosphere. It’s difficult to debate the questionable stuff, e.g. the feedback mechanism between CO2 and water vapour, if you can’t get past observable basic principles.
Ah, I see. Thanks. So the extra CO2 never becomes part of the natural flux? It lasts for ever?
It can end up in the ocean, but that can happen all at once so lots sticks around ~500 years and some for thousands.
And, what’s the evidence for this?
It’s described in many places, including the review I’ve already linked to
For a post that was deemed stupid and that should be taken down, this does seem to have produced rather a lot of comment traffic
Yeah – I’ve taken it as an object lesson of the pointlessness of talking to at least some contrairians. If something this simple takes so much effort to explain…
Sorry I’m so slow, David, but it’s ungracious to call me a “contrarian.” To what have I been contrary?
I should point out that in answer to my question you’ve given no evidence of 500-1000 years of “sticking around” because model output is not considered evidence. What made you give 500-1000 years when the abstract you cite says “The models agree that 20–35% of the CO2 remains in the atmosphere after equilibration with the ocean (2–20 centuries).” Why don’t you mention 2000 years?
Why do you ignore the 36 peer-reviewed papers cited above by Bob D describing actual observations of residence times of airborne CO2 which range from 5 to 10 years? They prove that the theoretical figures you cite are wrong.
….and I’m done. If after all this you can’t understand the difference (and sitll claim to not be a contrarian!) then i really do give up.
But models can never trump observations! Now that IS stupid.
Please try and understand, this really is the last time I’m going to try this: the measurements are about how long a particular molecule of CO2 stays in the atmosphere, not how long an increase in CO2 concentration takes to equilibrate. They’re different things, so once can’t “trump” a model of the other.
Thanks for your patience. I’m really trying, too. I’ve looked it up:
e·quil·i·brate
Verb:
Bring into or keep in equilibrium.
Approach or attain a state of equilibrium.
I’ll try to keep this simple. When an “extra” charge of CO2 reaches the atmosphere, from the sea, or living organisms, or a steel mill, what is not in equilibrium?
Again, without having read the articles in question, let me make one or two observations.
While you are correct, David, in stating that residence time and the so-called ‘relaxation time’ are different, they can both be measured together if one uses an impulse for the experiment. Fortunately, such experiments are fairly common and, again, I presume that this was done in the papers cited elsewhere.
Take a non-extinct volcano and wait for an eruption (thank you Pinatubo et al.) . If the eruption is short then the extra CO2 added to the atmosphere is an impulse. The reaction to an impulse is for a sharp initial rise, usually followed by an exponential decay. The exponential decay gives the relaxation time (think half-life for radioactive decay). The average residence time is calculated by summing the fraction of material that disappears at each time multiplied by the time since the impulse.
So you can see that both the relaxation time and the average residence time are closely related and will be of the same order of magnitude. Furthermore they should be reported together in the articles cited elsewhere or can easily be derived therefrom.
Thanks Huub, this is my point – the research measured the actual time taken for the impulse (or perturbation) to wash away. It didn’t take any theoretical considerations into account – it simply measured what happened. Within four to ten years the excess CO2 had been re-absorbed.
Now naturally the situation is complicated by a small but constant stream of CO2 being added from fossil fuels, as opposed to a single impulse, but the point remains that an amount of CO2 added to the atmosphere doesn’t hang around for hundreds or thousands of years.
You want to point out Mt Pinatubo in the CO2 record? The amount of CO2 released in that eruption was about what humans emit in half a day, there’s no signal there for us to measure so that’s certainly not what Bob’s numbers are on about.
The ocean’s surface is fairly CO2 saturated so the process relies upon recirculation of CO2 from surface waters to the deep ocean. There is the bottle-neck. The ocean becomes more acidic as it absorbs more CO2. Net world-wide deforestation also reduces the absorption potential. That is why the amount of CO2 in the atmosphere is increasing. Many scientists believe that it would take 500-1000 years to absorb a significant pulse of additional CO2.
Simon:
References please?
Contrary to your statement, Khatiwala et al (2009) show that ocean uptake rates have increased in line with atmospheric increases, from 1765 – 2008.
Liu et al (2010) showed the opposite. The worldwide Leaf Area Index (LAI) has increased from 1981-2006 at 0.0013 per year, with up to 0.0032 per year in the middle and high latitudes. Higgins and Scheiter (2012) believe that higher CO2 levels will allow shifts in local regions (such as savannas) towards forestation, away from lower CO2-absorbing grasslands.
Probably true, but the uptake increase is slower than the increasing amount of CO2 being emitted. Acidification is not a good thing either. Most of the deforestation is occurring in tropical areas (e.g. the Amazon and indonesia). Boreal forests grow slower than tropical forests so LAI can be misleading. The amount of CO2 in the atmosphere is increasing. You keep implying that this excess CO2 is being absorbed and that is not true.
David at 9:34am.
It’s a good thing that the residence time studies don’t rely on simply the concentration of CO2 then. If you look at the link Bob D included above http://c3headlines.typepad.com/.a/6a010536b58035970c0120a7895f54970b-pi you will see that the majority of the studies used natural carbon-14, i.e. they looked at the change in the ratio of natural carbon-14 to that from non-natural (mineral) sources of carbon (not 14). This provides a much more discerning method.
Other of the estimates were from “Bomb Car-14,” which use the impulses in CO2 caused by atmospheric nuclear tests to help determine the residence time.
I hope that this helps your understanding of the methodology.
Huub – yes, that’s my point, if you are measuring turnover in over in isotopes you are measuring the rate of exchange for a particular molecule – not the lifetime impact of emission. I don’t think this is a hard concept to understand….
Simon:
Not according to the paper, the uptake is in step with the CO2.
There has been a net increase in LAI worldwide, which means more plant “area” to absorb CO2. The boreal and temperate forests make up an enormous area, and they have been increasing in size (Siberia, Europe, USA). The tropical regions have also increased. The tropical losses in the Amazon have more than been made up for by increases in sub-Saharan Africa.
It is true, but not ALL the excess is being absorbed right now. It takes four to ten years to be absorbed, and in the meantime more is being added to the atmosphere. That is why we see a gentle increase in CO2 concentration of about 1.6 ppmv/year.
But we don’t see a corresponding increase in global mean temperature. The trend since 1997 (15 years) is flat (HadCRUT3).
David,
Well there you have me. I feel sure I understand very well what the concept is. It matters not whether one talks about Carbon-14 or not. It is the residence time of carbon dioxide we are discussing. Carbon dioxide will behave the same way no matter its isotope. Only if carbon is locked up for a long time will the concentration of Carbon-14 decrease, as we see in that coming from volcanos. The residence time of carbon-14 (dioxide) in the atmosphere is the same as that of carbon-13 (dioxide) and carbon-12 (dioxide).
If my understanding of this is incorrect, then I am sure that you will be able to correct me. If that is the case however, then may I beg to differ on how hard the concept is to understand?
The “residence time” for a CO2 molecule isn’t changed by its isotope.But it’s not residence time we care about. We want to know how long an pertubation in CO2 concentration will stick around. It doesn’t matter if a “new” molecule goes into the ocean to be replaced by an “old” one, any more than it matters the particular notes I take out of my bank account aren’ t the same as the ones I put it in (well, back when money worked like that anyway).
As it happens It takes a long time for a new glut of CO2 to equilibrate, and measuring isotopes can’t tell us how long.
“We want to know how long an pertubation in CO2 concentration will stick around”
And how effective it is as additional energy transfer medium. Case in point, the effectiveness of CO2 in the thermosphere to transfer large amounts of CME energy back out to space:-
Solar Storm Dumps Gigawatts into Earth’s Upper Atmosphere
http://justallinone.com/myblog/?p=171
“Carbon dioxide and nitric oxide are natural thermostats,” explains James Russell of Hampton University, SABER’s principal investigator. “When the upper atmosphere (or ‘thermosphere’) heats up, these molecules try as hard as they can to shed that heat back into space.”
“For the three day period, March 8th through 10th, the thermosphere absorbed 26 billion kWh of energy. Infrared radiation from CO2 and NO, the two most efficient coolants in the thermosphere, re-radiated 95% of that total back into space.”
David 2:38pm
On the contrary David that is EXACTLY what these experiments do tell us. Remember that the residence time and the relaxation time are linked. If the response to an impulse follows a strict exponential decay then there is a mathematical relationship between residence time and relaxation time (although I can’t say what it is off the top of my head.) So to say residence time is irrelevant is missing the point.
Let me see if I can explain why using isotopes is also valid.
Let us say that we have a sudden addition of carbon-14 (dioxide) to the atmosphere; we can see the presence by an increase in the ratio of carbon-14 to total carbon. As carbon dioxide moves from the atmosphere to the sinks there is no difference in the uptake of carbon-14 (dioxide) compared with other isotopes; what happens to the carbon-14 happens to all the carbon. So, as we watch the decrease in carbon-14 we are watching the removal of all carbon dioxide from the atmosphere. (Obviously it is being made up by that coming from the carbon sources but that’s not the point here.) This gives us directly the relaxation time for a perturbation in carbon dioxide.
OK, so now think about an increase in the total amount of carbon dioxide, an increase in concentration. We know how fast the carbon dioxide is lost to the sinks because we know what the relaxation time is. (This is not strictly true because an increase in the total concentration will increase the movement of carbon dioxide to the carbon sinks which we didn’t factor in, but this will not reduce the relaxation time much.)
So, hopefully you can see that the experimental determination of the residence times and relaxation times are valid.
Huub – do you understand the different between “flux” of CO2 moving between ocean and atmosphere and a net flow from one to the other?
David, it seems I must congratulate you on achieving your PhD although I have no idea in what area you did your thesis and whether it provides you with deeper insight into the topic at hand. I hope, however, that you explained yourself well in your thesis; you are not doing so here. Your comment
“As it happens It takes a long time for a new glut of CO2 to equilibrate, and measuring isotopes can’t tell us how long.”
is a sweeping statement without explanation or reference. Your next “Huub – do you understand the different between “flux” of CO2 moving between ocean and atmosphere and a net flow from one to the other?” is a cryptic question that does not seek to enlighten.
Would you please explain your idea since you have not managed to do so yet in this discussion thread. I do not believe the issue is with the Richards, Bob and me; I can assure you that we are not stupid. Nor can your idea be as simple as you seem to think.
So, you have an interested audience, capable of logical thought and wishing to understand your point of view. Keep it simple and clear and take as much space as you need. I’m sure that those reading this for enlightenment, but not contributing to the discussion, will appreciate your efforts as much as I will. 🙂
What David has been saying makes perfect sense to me. The problem is that some people (including the creator of the C3 chart) are confusing residence time and lifetime.
Residence time is the average time a given molecule stays in the atmosphere.
Lifetime is how long before a molecule is removed permanently and not just exchanged.
The residence time is only a few years. Lifetime is probably hundreds of years.
Simon:
This is just arm-waving, until you can prove that the carbon sinks (ocean, biosphere mainly) are saturated and can absorb no more CO2.
In neither case (see papers above) is this true.
On the matter of residence times, lifetimes and fluxes.
The accumulation of any matter–CO2, water vapour or poodles–depends on the difference between what is added and what is subtracted, what are being referred to here as fluxes. In terms of CO2 the man-made addition is about 3% of the total. We can expect the accumulated amount of CO2 in the atmosphere to increase slightly, and slowly, until a new equilibrium, is reached.
The residence time of the material (CO2, water vapour or poodles, remember) is simply the accumulated amount divided by the flux (either flux if we are at steady state). Without having taken the time to read any of the papers with regard to CO2, I have to assume that this is what they did because that is the definition of the term residence time. Apparently this is four to ten years. Man-made CO2 appears to behave in the same fashion as natural CO2 for some reason.
So, the only question here is how quickly the system will be restored to equilibrium by various feedbacks in the system and what the new level might be. That there will be an equilibrium is apparent since the increased concentration of CO2 in the air will increase that in the ocean, which has orders of magnitude more capacity. This equilibrium can be expected to be attained in the same timescale as the residence time. Why can I say this? Because that is one of the parameters that determines the equilibrium accumulation.
What are we worrying about then? That the accumulation of CO2 in the atmosphere is increasing faster than we would expect from man-made additions? Well there are two reasons why this might be the case, 1) man-made CO2 is different from natural CO2 and stays in the air for longer (sorry my humour gets the better of me sometimes; the real 1) is that, somehow the carbon sinks no longer react as they should for some unidentified reason) or 2) that more ‘natural’ CO2 is being freed from the rocks and the sea due to the warming over the last 800-1000-odd years. Judging by the historical record it is the latter..
I hope this helps with the understanding of the matter under discussion.
Thanks a lot, Huub. You make it sound simple (though I like the idea that we create a different kind of CO2).
So the equilibrium to be reached is between the CO2 sinks. Because the new charge of CO2 puts slight pressure on the ocean and the rest of the biosphere to accept a little more, and then we have equilibrium. But since it’s a dynamic system, equilibrium will never actually be reached.
If the observed global increase in atmospheric concentration is sourced from the hydrosphere, as a result of increased warming, there would have been no increase over the past 15 years.
As the increases have continued apace (according to Hawaii measures), the source must be something other than warmth – perhaps fossil fuels?
Well observed, Stanley. It’s curious that the rise in CO2 concentration remains steady. If it comes from human emissions, it certainly displays none of their variability. But what else could it come from? Might there be some lag in CO2 out-gassing from the ocean?
Richard:
I’m not sure if this was a rhetorical question or not, but yes, the Vostok ice core data shows a lag between temperature rise and CO2 response of several hundred years. So the current increase is two-fold: past temperature rise together with human emissions.
Bob, thanks for that. It was an honest question. In focusing on the instantaneous process I overlooked the longer term.
I’m thinking that David Winter’s “lifetime” is but a logical description of the continuation in the air of added CO2. It’s independent of individual molecules. When the concentration goes up, it stays up until it goes down. Calling it a lifetime magically obscures the simple fact that the concept depends on the concentration always rising, because then you can call it hundreds or thousands or tens of thousands of years without evidence and nobody can refute it.
But on the smallest reduction in concentration, some molecules have permanently retired from the atmosphere without being replaced. What of their lifetimes? They’re cut short. Since this happens each year, according to the Mauna Loa record, it kind of falsifies the idea of a lifetime being anything like a hundred years or more. Because why should a few molecules have a short lifetime while the rest live longer?
On reflection, it seems that to use residence times as the basis for comparing the greenhouse effect of gases is complex and misleading. It would be more straightforward to measure and compare the different instantaneous effects, because they certainly occur at the speed of light and have no future effect beyond the future composition of the atmosphere.
Or what am I missing?
Richard T:
Yes, I think the important question is not residence time, but climate sensitivity. After all, we can measure the rate of CO2 rise relatively accurately, but who cares if CO2 rises at 0.4% annually or hangs around for decades if the effect of the instantaneous CO2 concentration is negligible?
Taking the last 15 years into account, we have to conclude that the effect of the rise in CO2 has been zero. It was a good test period – no volcanoes, and a roughly equal number of El Nino and La Nina events. It is long enough to contain a full 11-year solar cycle, and is also long enough to provide a reasonable statistical certainty in our result.
The question the warmists must now answer is this:
“What caused the lack of increase in global temperature over the past 15 years at a time when CO2 increased monotonically and why did you not predict this?”
And the obvious corollary question:
What confidence do you have that whatever influence you named in answer to the question above is now removed, and will therefore result in a continuation of CO2-induced warming over the next 15 years?”
For extra marks, I personally would like to know the answer to the following:
“Hansen (2005) states that the warming seen during the 1990s must continue into the future, because of the ‘warming in the pipeline’, as he puts it. Even if CO2 concentrations had stabilised in 2000, the warming must have continued, otherwise his modelled planetary imbalance of 0.85W/m2 could not be occurring.
What ramifications then does the 15 -year current stasis have for his theory of a planetary imbalance?
Bob,
Heh, you don’t want much, do you? It’s almost as though the mere assertion of approaching calamity isn’t enough for you, you extraordinary serf. It seems you demand proof of predicted peril!
Richard,
Yes, I’m funny that way. 🙂
Congratulations folks, this may be the 80th comment on a post that was deemed “rubbish” by David Winter.
PS David congrats on your PhD
It’s great to have such a fruitful discussion. And yes – well done, David.
Simon,
That sounds difficult to prove, and means you cannot know that any “lifetimes” have ended until the atmospheric concentration starts to decline. When a molecule leaves the atmosphere, how do you know whether another molecule, perhaps thousands of miles away, has replaced it or whether it has entered the atmosphere on its own terms?
Aren’t we making an assumption that the planet has a natural level of CO2 etc that it will tend to? How do we know this?
If we pump up the concentrations to 600ppm, how do we know that it will naturally tend downwards towards a certain value?
OK, once more because anything is better than marking lab reports….
We have a carbon cycle on earth. CO2 exists in rocks and the ocean (as carbonates mainly), the atmosphere and the biosphere (organisms). Single cabron dioxide molecule move between these reservoirs all the time (animals breath, rocks weather oceans give up CO2 where they are warm and suck it in where they are cold). In total, sometime like 200 gigatonnes of CO2 moves between these reservoirs in a year.
Because of these fluxes the time a single molecule spends in one reservoir is pretty small (that goes for the ocean too of course)
But now we are adding a lot of extra fossil CO2 to the system. The particular molecules we release into the atmosphere will be subject to the same forces and the non-fossil CO2 so they’ll get exchanged with ocean CO2 too. But that doesn’t tell us how quickly a CO2 glut is removed form the atmosphere – for that we need to know the rate at which the ocean is drawing down (and not simply exchanging) CO2. We can measure this, it’s close to 2 gigatonnes a year. At that rate, given the amount of extra CO2 we’ve added it will take on the order of hundreds of years for the CO2 we’ve already added to the atmosphere to get sucked up by the ocean. Even that model is too simple, and if you factor in what we know about the carbon cycle you find there will also be a “long tail” that our descendents will be stuck with for a long long time.
None of this requires a “natural level” of CO2 (it’s just physics, and this point seems to argue against any lifetime for CO2). or accounting which molecules are exchanged and which are drawn down (it’s a net effect after all). It’s also obvious that the recent rise in CO2 is all down to us, because the ocean is a sink for carbon, not a source.
David:
Good, now we’re getting somewhere. Can you provide that reference for me, and also a reference for the equivalent biosphere draw down rate?
Sure. The land sink is around 2.8 GT – our emissions minus the atmospheric increase (~40% of emissions) and the ocean increase.
Do you think this land sink value is constant or will it change with increased CO2 fertilization?
(Ignoring issues around land use and deforestation for the minute)
Full paper also available (pdf).
David, the abstract says:
Note that a “data-based estimate” is fundamentally a guess.
This study takes information from estimates and models, but not measurements. I am puzzled by your statement “we can measure this.”
Sweet, that explains that figure.
Two things to note:
1) It’s not actually a measured result, it’s an estimate based on models. The same models that failed to predict the 15 year temperature stasis.
2) The paper states “the global uptake scales approximately linearly with changes in the global anthropogenic CO2 inventory.” This reinforces Khatiwala et al (2009) above. It means that there is currently no saturation as Simon claimed – the more CO2 in the atmosphere, the more the uptake. If we had reached saturation, the uptake rate could not scale any further.
So you’re finally happy to admit the graph you linked to is talking about something other than the the lifetime impact of carbon released today. And that the OP is based on a fairly basic misunderstanding about how the climate system works?
Also please note that what I actually said was that the oceans’ surface becomes CO2 saturated, hence the need for ocean circulation models.
David,
Err, OP – original post?
Yes. I’m still waiting for someone to actually update their ideas based on new information, but perhaps that’s a forlorn hope…
I’m still thinking about your confident assertion that we can measure the oceanic removal of CO2 and your subsequent reliance on guesswork.
You say the ocean is only a sink of CO2, but not when it’s warming or has been warming in the last several hundred years. Which leaves the door wide open on non-human sources of CO2.
It’s not “guess work”, I’m not interested in playing the Gish Gallop, I’d just to think there was even a small chance you’d take new information on board. That doesn’t seem to be the case.
Yes, I know what a Gish Gallop is, but thanks for the link. I’ve never heard it from anyone but a committed warmist, and here it is again; obviously a favourite debating technique when things get difficult.
But to your curt dismissal of our mental acuity: How would you know what I knew and whether it’s new? Actually, I did hear new material from you, thanks, but now I’m asking further questions, if you don’t mind. You cited the paper that used “estimates.” The word is defined as “guess.” The two words are synonyms, for heaven’s sake! You can’t persuade me otherwise no matter how hostile you try to sound.
So, if the paper relies on a guess, you can admit it, or cite another, but it’s pointless to argue that an estimate is not a guess.
So, I’m waiting for your explanation, because otherwise your assertion that the ocean permanently sucks up about 2 GT of CO2 annually is still unconfirmed.
Thank you David for an excellent explanation.
Bob D: The world is warming,we can agree to disagree as to why. Starting your base at 1997 so as to encapsulate the 1998 mega El Nino event doesn’t change that.
and Simon gets the prize for the 100th comment.
At least we get some “conversations” going round here 🙂
Simon,
I’d be curious to see a reference for “The world is warming” for the last 15 years.
Simon:
The temperature record is what it is. For the last 15 years, with El Ninos and La Ninas galore, no volcanoes (unlike the 1990s) and a full solar cycle we see no warming, in complete contrast to the dire predictions that were made by the alarmists at the end of the 1990s.
And regarding the super El Nino of 1998, let’s not forget that the alarmists made great use of it to show a warming trend over the 1990s. The problem for them is that it hasn’t been repeated since then, so now suddenly it’s inconvenient.
Let’s also remember, while we’re on the subject, that there was another super El Nino not long before it, in 1982/83. Its ONI was 2.2, compared with the 1998 ONI of 2.4, so it was pretty close.
However, we don’t see its effect on the temperature record because, purely by chance, the huge El Chichon eruption completely masked it by causing a 16% drop in solar insolation. Had the eruption not happened right then, the temperature history over the past few decades would look a little different. The baseline would be higher, and the trend from 1980-2000 would be lower.
Equally, if we had had a large eruption during the decade 2000-2010, the average temperatures would have been even lower. So the argument that that decade was the “warmest on record” must also take into account that there were no significant volcanic eruptions during that time.
But these are just speculations. At the end of it all, there has been no warming since the late 1990s. Explain please.
I notice that to date not one warmist has actually ever attempted to explain the lack of warming (apart from Trenberth’s extremely desperate “it’s hidden where we can’t see it, or even work out how it got there”). They simply deflect the argument one way or the other.
Either they deny everything (“it’s still warming”) or they waffle on about “long-term trends” or they just change the subject and talk about Arctic ice or something else.
or they chose a dataset that does show warming (like GISSTemp) and then accuse you of cherry picking by selecting HadCrut3
and speaking of Arctic Sea Ice, this graph shows the “shocking” new minimum.
http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm
The three weeks of data starting from Aug 7th or so shows the graph diverging from the ensemble.
This apparently signifies the end of the world, or perhaps a localised weather phenomenon, depending on your point of view.
Some people see only what they want to see and cherry-pick their data to prove it.
I look at that chart of Arctic sea ice extent and I am shocked.
Some people see only what they want to see and cherry-pick their data to prove it.
I look at that chart of Arctic sea ice extent and I am shocked
Why?
The chart shows the ice loss taking a fast increase from the norm on August 7th or thereabout.
Did “global warming” suddenly get an extra set of teeth on Aug 7th or was there a weather phenomenon that caused this loss?
After all, there was nothing particularly unusual before this date.
I
Simon, assuming you and he are the same, my response (in moderation) is this
And I should add that everyone is getting their knickers in a twist over that divergence, not the rest. That is the bit about the records being set
[Update] Comment out of moderation.
I’m sorry, but this whole ridiculous excercise just confirms to me how disconnected from science the “debate” contrarians want to have is.
This isn’t even slightly controversial, the uptake but has been measured (the word estimate isn’t synonymous with “guess” in normal English, and it certainly isn’t in science). The ocean is a sink – how else would it be getting more acidic? The extra CO2 is ours – the increase in atmospheric CO2 is less than the amount we emit!
If something this simple takes this much effort I really don’t know what point there is in talking about anything interesting.
David, calm down.
Apart from your mistake over the meaning of estimate (look it up!) it sounds just fine. If you still disagree, please describe how the two meanings differ.
What you say is quite straightforward. All I’m asking for is your references. That’s not unscientific. Nor is it unscientific to question those references. If you noticed shortcomings in them, you would question mine.
If you have other references to measuring those oceanic uptakes, pass them on.
We could talk about Windmills if you like. That always gets me lively
Can someone remind me what we were actually disagreeing about?
I think it was residency times for CO2
I am not doubting that CO2 levels are increasing.
“I’m sorry, but this whole ridiculous excercise just confirms to me how disconnected from science the “debate” contrarians want to have is.”
Come, come David. We are looking for no more than the level of proof you undoubtedly displayed in your thesis. You’ve managed to get across the fact that residence time and relaxation time can be significantly different, although I would give a different explanation of it.* So you are making progress. You should not, however, get huffy when we ask for proof and question it. This is scientific discussion, not a social one, and we have evidence aplenty of scientists perverting the peer review process and the trust people have in science. This means we require references for statements made and that those references will be reviewed and dissected.
You have made the statement that, contrary to the usual situation, the relaxation time is vastly larger than the residence time in the case of carbon dioxide uptake. Your reference is based on global circulation models, which we already know are badly flawed. (They are describing a complex, non-linear, chaotic process and have failed all predictions. Even the IPCC considers their outputs to be “projections,” not “predictions,” i.e. the outputs have no scientific rigour.) I’m sorry, but not good enough yet.
* For those readers still confused this may help. Remember that the amount of matter that accumulates in a pool is determined by the difference between the flows from sources and the flows to sinks. The residence time is defined as the total amount in the pool divided by the flows to sinks. The relaxation time (a type of half-life) depends on the amount in the pool divided by the difference between flows in and flows out. If the flows from sources, and to sinks, is large then the turnover of matter in the pool will be fast. If the difference between the flows is small then it will take a long time for added matter to be removed from the pool.
“This isn’t even slightly controversial, the uptake but has been measured (the word estimate isn’t synonymous with “guess” in normal English, and it certainly isn’t in science). The ocean is a sink – how else would it be getting more acidic? The extra CO2 is ours – the increase in atmospheric CO2 is less than the amount we emit!”
If indeed the oceans are getting more acidic overall it is pretty miniscule and there are many possible culprits. From my calculation if all the carbon from the total known world reserves of fosil fuels – about 1000 GTC – were transferred as CO2 to the oceans and stirred up a bit the CO2 in the ocean would have increased by about 2.5%. Big deal.
Freeman Dyson has written some interesting stuff about the carbon cycle, suggesting to me there is much we don’t understand.
This new paper has some interesting conclusions:-
The phase relation between atmospheric carbon dioxide and global temperature
* Ole Humlum,
* Kjell Stordahl,
* Jan-Erik Solheim
2012
http://hockeyschtick.blogspot.co.nz/2012/08/new-blockbuster-paper-finds-man-made.html
A couple of highlights:-
► Changes in global atmospheric CO2 are lagging about 11–12 months behind changes in global sea surface temperature.
► CO2 released from use of fossil fuels have little influence on the observed changes in the amount of atmospheric CO2, and changes in atmospheric CO2 are not tracking changes in human emissions.
There is also this 3 year old paper from Bristol that suggests that the proportion of anthro CO2 is not increasing
http://wattsupwiththat.com/2009/11/10/bombshell-from-bristol-is-the-airborne-fraction-of-anthropogenic-co2-emissions-increasing-study-says-no/
Full paper is here.
Interesting paper. Note that they use actual measurements, not models. Fig. 5 is a good summary, showing how the measured CO2 changes are driven by the ocean temperatures, with a lag.
Also this figure.It’s quite clear that the anthro correlation is not good. Bear in mind that the expected correlation is fossil fuel increase first, global measured CO2 second.
All of those Fig 13 locations: Alert; Mauna Loa; Ascension Island; and the South Pole, are completely insensitive to any fossil fuel change up or down.
It’s clear in Fig 5 on the other hand that ocean surface air temperature regulates release or uptake of CO2.
Remind me again, why do we need an ETS to combat this natural phenomenon?
Surely the annual saw tooth configuration of the Maunu Loa figures can only be explained by temperature driving CO2 rather than the other way round..
No, it’s attributed to variable seasonal output of CO2. Most forests are in the Northern Hemisphere, so there’s an asymmetry to the seasons. But in looking for a reference, I’m wondering how or whether that explains the actual decrease in CO2 during May-October.
On reflection, it was incorrect to say “ocean surface air temperature regulates release or uptake of CO2” because the air temperature is a secondary response to ocean surface temperature and I don’t think warmer or cooler air forces CO2 in to and out of the ocean (not that I actually know).
The relationships in that case should really be something like this perhaps:-
Ocean surface temperature regulates => ocean surface air temperature response
Ocean surface temperature regulates => CO2 response in the air.
Ocean surface air temperature response leads => CO2 response in the air.
Where Did All The CO2 Go?
http://theresilientearth.com/?q=content/where-did-all-co2-go
A recent study in Nature by A. P. Ballantyne and colleagues has shed new light on the short term carbon cycle with a painstaking survey of carbon sources and atmospheric CO2 levels over the past 50 years. The main result of the study can be gleaned from the letter’s title, “Increase in observed net carbon dioxide uptake by land and oceans during the past 50 years.” More detail is available from the paper abstract:
One of the greatest sources of uncertainty for future climate predictions is the response of the global carbon cycle to climate change. Although approximately one-half of total CO2 emissions is at present taken up by combined land and ocean carbon reservoirs, models predict a decline in future carbon uptake by these reservoirs, resulting in a positive carbon–climate feedback. Several recent studies suggest that rates of carbon uptake by the land and ocean have remained constant or declined in recent decades. Other work, however, has called into question the reported decline. Here we use global-scale atmospheric CO2 measurements, CO2 emission inventories and their full range of uncertainties to calculate changes in global CO2 sources and sinks during the past 50 years. Our mass balance analysis shows that net global carbon uptake has increased significantly by about 0.05 billion tonnes of carbon per year and that global carbon uptake doubled, from 2.4 ± 0.8 to 5.0 ± 0.9 billion tonnes per year, between 1960 and 2010. Therefore, it is very unlikely that both land and ocean carbon sinks have decreased on a global scale. Since 1959, approximately 350 billion tonnes of carbon have been emitted by humans to the atmosphere, of which about 55 per cent has moved into the land and oceans. Thus, identifying the mechanisms and locations responsible for increasing global carbon uptake remains a critical challenge in constraining the modern global carbon budget and predicting future carbon–climate interactions.
Doing some housekeeping of pdf’s that seem to accumulate on my system like bacterial reproduction. Decided that this one was a “keeper”:-
An Unsettling Look at the Settled Science of Global Warming
Part 1: Scientific Discussion
John Eggert P. Eng.
http://tallbloke.files.wordpress.com/2010/07/agw-an-alternate-look-part-1-details-c.pdf
Wrt radiant energy absorption by CO2 at increasing concentrations, John Eggert describes some IPCC sleight-of-hand:-
The IPCC manufactured a straight line to represent a curve with a maximum.
Unfortunately, the pdf’s have reproduced in bacterial manner so that I’ve now accumulated another 2 (Sigh):-
An Unsettling Look at the Settled Science of Global Warming
Part 2: Layman’s Discussion
http://tallbloke.files.wordpress.com/2010/07/agw-an-alternate-look-part-2-for-laymen.pdf
An Unsettling Look at the Settled Science of Global Warming
Part 3: Policy Maker’s Summary
http://tallbloke.files.wordpress.com/2010/07/agw-an-alternate-look-part-3-summary.pdf
In the same vein:-
HANSEN MARS CHALLENGE
Norm Kalmanovitch, P Geoph
http://icecap.us/images/uploads/HANSENMARSCHALLENGE.pdf
You do find some pearlers Richard.
Keep clearing out that closet!
SOON AND BRIGGS: Global-warming fanatics take note
Sunspots do impact climate
The hallmark of good science is the testing of plausible hypotheses that are either supported or rejected by the evidence. The evidence in BEST’s own data and in other data we have analyzed is consistent with the hypothesis that the sun causes climate change, especially in the Arctic, China and the United States. BEST’s data also clearly invalidate the hypothesis that CO2 is the most important cause of observed temperature changes across the United States.
Given the wide, and perhaps at times excessive, interest in tying carbon dioxide to climate, there has been relatively little work investigating the solar-climate connection. The scientific community has proved the wisdom of Ralph Waldo Emerson, who said, “The sun shines and warms and lights us and we have no curiosity to know why this is so.”
http://www.washingtontimes.com/news/2012/sep/6/global-warming-fanatics-take-note/