Recently 250 scientists signed a letter on climate change, I suggest reading it as it’s being touted as a big story in the news. As we are supposed to be the technical skeptics, there are a few issues which are easy pickings in the letter. The letter is an undisguised attempt to alter public impressions of uncertainty in climate science. It is no coincidence that uncertainty is the key issue which skeptical scientists have with institutional climate science. These uncertainties are far greater than even the technical public realizes, I didn’t understand the magnitude of the uncertainty even two years ago.
After opening sentences claiming ‘attacks’ on good climate scientists, the letter discusses uncertainty and some non-sequitur examples of sciences that contain far different levels of uncertainty, five main dogmatically “proven” points are listed, of course I couldn’t help but answer:
(i) The planet is warming due to increased concentrations of heat-trapping gases in our atmosphere. A snowy winter in Washington does not alter this fact.
Nobody has measured the total heat content of the earths ocean and atmosphere to a level which clearly separates current warming from natural. Even small fluctuations in humidity can cause a slight atmospheric warming, and there is substantial uncertainty on this issue. Climate models used to prove this statement, fail statistical testing and papers which show this failure have been actively blocked from the main stream science (climategate style). This does not negate the fact that some warming is created by CO2, but the amount of warming CO2 creates, could be less than the natural warming.
(ii) Most of the increase in the concentrationof these gases over the last century is due to human activities, especially the burning of fossil fuels and deforestation.
Again, this is overstated. Can someone find a link which shows the percentage of isotopes from CO2 which are presently in the atmosphere from combustible fuel? The last I read, about 30 percent could be attributed to combustion, the rest could have been released from oceans as surface water warmed. However, even the 30 percent could be in error as it’s calculation didn’t take into account some of the short term recycling and re-release from decaying plant material. The amount of contribution by humans is, amazingly enough, also uncertain.
(iii) Natural causes always play a role in changing Earth’s climate, but are now being overwhelmed by human-induced changes.
Dogma, nothing more. Any climate change has been so small as to be difficult to detect with current instrumentation. I’ve read no convincing papers which prove this sentence and most papers I’ve read, still attribute the majority of ‘changes’ to nature. This statement is not supportable by the literature.
(iv) Warming the planet will cause many other climatic patterns to change at speeds unprecedented in modern times, including increasing rates of sea-level rise and alterations in the hydrologic cycle. Rising concentrations of carbon dioxide are making the oceans more acidic.
The effects of a warmer planet on weather are wild speculation and an embarrassment to the climate community. Damage and destruction are nearly 100 percent of the time, wildly overpredicted – in peer reviewed publication no less! Beneficial effects are often ignored completely. As climategate has shown, there are systematic efforts in place to eliminate dissent and reasoned thought on such issues. I have no doubt that a warmer earth is preferable for life in general, a greener planet with more land, food and greater biodiversity. Of course these conclusions can be found in non-climate journals, but are widely suppressed in organizations such as the IPCC.
The ocean acidification data is of very very poor quality, but is presented as though it is known fact. I can’t even read a graph that shows the Ph of the ocean to hundredths back in 1900 – prior to the airplane. Even reading about measured changes in ocean acidification with respect to 100 years ago is known to kill brain cells. The reason it’s so often stated is because CO2 does cause acidification, just as it does retard heatflow, the uncertainty of the magnitude of Ph feedbacks are again the main issue. They know some acidification sounds reasonable but how much is what is unknown.
(v) The combination of these complex climate changes threatens coastal communities and cities, our food and water supplies, marine and freshwater ecosystems, forests, high mountain environments, and far more.
This is the ecofreak side of the scientists coming out. Sea levels have been rising for hundreds of years and have slowed in the last 10. Changes in many glaciers are a result of precipitation not warming, dark particulates from unscrubbed coal plants in others. We would have to be stupid to think that food supply wouldn’t increase on a warmer planet with faster growing plants, yet that’s exactly what they need to say to demand action.
The religious undertones of these declarations are hard to miss. The wildly overstated belief, the powerful declarations of certainty, the demand for appeal to higher authority, all backed up by very weak statistics and poorly vetted climate models. Early in the letter, the scientists who apparently don’t read enough blogs wrote:
Even as these are overwhelmingly accepted by the scientific community, fame still awaits anyone who could show these theories to be wrong.
The draw of their offer of fame is too much for me, after all, who doesn’t want fame with zero compensation. I present the following alternate theory of global warming – the Null theory, which is basically the oft repeated mantra of the technical skeptic:
Climate models show warming which is statistically exaggerated with respect to measured data, as demonstrated by a number of analyses. Papers demonstrating this, are being actively blocked from publication. See treesfortheforest, Lucia, and ClimateAudit for examples.
The significance of measured warming is being exaggerated with respect to historic natural variation. Historic temperature prior to 1900 is unknown. Hockey stick temperature graphs from proxies are false papers representing nothing but statistical anomalies on unverified data. Large scale physical evidence shows that earth’s temperature was warmer than today in past millennia. No evidence has shown that currently measured minimal warming is anything outside of natural variation.
Damage from predicted warming is exaggerated, there is no evidence that warming will cause any problems whatsoever. Massive flooding is highly unlikely to the point of near impossibility, extreme weather patterns are undemonstrated, violent global tipping points are highly unlikely. Each of these claims by institutional science are wildly uncertain and are currently failing tests against measured data.
The atmospheric life cycle of CO2 is unknown and functional absorption mechanisms remain undefined.
AGW theory is possibly true to some extent having sound basis in that CO2 does retard heatflow, but the complex and poorly understood response of the atmosphere means that magnitudes and effects of this change are not well known. This huge uncertainty is easily verified by the wildly different predictions of various consensus climate models, however the uncertainty extends beyond the range of model predictions due to like minded assumptions forming the basis of today’s models.
Finally, the certainty to which conclusions are expressed by the scientists in the press and in papers, exceeds reasonable bounds. Hide the decline of Climategate showed a single instance of many known brushed aside uncertainties in climate science. Such instances of suppressed uncertainty are far from uncommon, and those of us who read the papers are fully aware of it. It is the certainty of both the magnitude of warming and the danger of warming on which reasonable disagreement lies.
I await my fame and fortune! haha. After writing the above, the stark contrast of opinion between the skeptical scientist vs the institutional science demonstrates the dogmatic undertones of the global warming consensus. As my opinions on different aspects of AGW have been hardened with ever more data, I now firmly believe that institutional AGW represents a direct attack on capitalism as a whole. In a stroke of lucky irony, the group called for an end to the McCarthy style attacks on climate science. hehehe.
Finally, the letter ends with the most obvious falsehood, and the single point where my personal greatest disagreement lies. The very last sentence reads:
The good news is that smart and effective actions are possible. But delay must not be an option.
In my opinion, no greater lie could ever be told to a population. There is simply no action which can be taken by our society without causing great economic harm to the people. We do not have the technology outside of a partial improvement using nuclear power. It’s no coincidence that every proposed action leads to higher taxation, greater government control and that some of the most popular solutions are the least effective and most expensive. Delay in my opinion is the single best option for limiting CO2 output. Even if the scientists guesses are completely right, delay of taxation and regulation means acceleration of the technological invention and eventual implementation of new energy solutions.
It is completely false that we have the ability to stop production of CO2 today, for scientists to openly claim otherwise disgusts me. New solutions are physically required to actually stop CO2 production and this statement proves beyond a shadow of doubt that AGW is politics not science. Like so many of a hidden political agenda, economic limitation and suppression of industry is a real goal.
the Air Vent 
Great fisking of a piece of rancid transparent propaganda.
Each and every point of that ignorant waste of writing is false.
Its authors deserve the disdain that history will grant them.
The NAS has been one of the driving forces behind the global warming scam, using budget reviews to force federal agencies like NASA, DOE, EPA, to finance the research of “scientists” that will find the “evidence.”
NAS has abused the trust of the American people. NAS cannot now regain that trust by signing and publishing letters like this.
With kind regards,
Oliver K. Manuel
Emeritus Professor
Nuclear & Space Science
Former NASA PI for Apollo
PS – It’s downright cold here in SE Missouri today!
very good graphic, to accompany this article.
our knowledge about climate, as seen by Willis Eschenbach.
sorry, Jeff, but not a single one of your arguments against the 5 main points is convincing in any way. you did just post what was on your mind?
Here is an explanation of the cause of recent climate changes:
1. Between 1983 and 2001, there was an increase of solar radiation at the surface of the order of 0.16 watts/sq m per year (Pinker et al, 2005).
2. The trend over oceans was greater at 0.24 watts/sq m per year with the overall trend for land based observations showing no significant trend (Pinker et al., 2005).
3. The data is consistent with ISCCP satellite data showing a global decrease in cloudiness (Pinker et al., 2005).
4. The data is also consistent with lunar brightness observations (Palle et al., 2003, 2004, 2005, 2006, 2009).
5. The data is also consistent with an observed warming of the oceans at this time. This ocean warming explains the atmospheric warming over land, without any greenhouse effect (Compo and Sandeshmukh, 2008). Using a climate model as a diagnostic tool, they show that the heat flows from the oceans to the atmosphere (opposite to the direction that the IPCC claims).
6. The magnitude of the observed solar radiation trend over 19 years is 4.5 watts/sq m compared to a computed trend in thermal IR increase due to greenhouse gases of 0.8 watts/ sq m.
7. The implied climate sensitivity from the above observations is 0.56 C for a CO2 doubling (Taylor, 2009).
8. Using an entirely different set of observations, Lindzen and Choi (2009) deduce the climate sensitivity is 0.6 C for a CO2 doubling.
9. Since about 2000, the cloud cover trend has shown a reversal with slightly increasing clouds, leading to a mild cooling of the oceans (Willis, 2008) and a downward trend in atmospheric temperatures over the last 8 years using either satellite or surface observations.
10. The overall conclusion from these observations is that any warming due to mankind’s influence is less than 1 C and will continue to be small in the coming years. The cloud cover variations could be unforced oscillations in a chaotic climate system or they could be forced by cosmic ray flux changes (Svensmark, 2007). The cause of the cloud cover changes is not relevant to the arguments presented here. My opinion is that most the natural climate variations are chaotic with each ocean basin have its own characteristic period and phase.
Summary: Unforced natural variations in cloud cover explain the recent changes in climate better than any anthropogenic theory.
Sod,
So what are you saying? Do you disagree?
How rare…
Jeff ID, when the scientists state the above advocacy mantra, I would think that we are clued into the political disposition of these scientists by it more than the science. The lead into that final statement is the usual apple pie and motherhood version of politician wrapping himself in the flag and then thinking we will all have to take what he says as the gospel truth. A true scientist, in my mind would never put together a few talking points about AGW, that are not all that controversial, and then without even mentioning any uncertainty bounds conclude that we will experience some very detrimental effects from future AGW.
The statements about deniers and special interests groups in a true scientific situation would have no bearing whatsoever on the science or importance to a scientist. Only the advocate and marketer of immediate AGW mitigation would be concerned. These kinds of statements simply show the silliness of the situation that results from the current lot of advocates/scientists (and I intentionally put advocates first).
I will concede that perhaps the motivation for this statement by the 250 scientists might have something to do with the “concerned” scientist’s interest in their own personal and material gains from the situation in the battle to keep the public in crisis mode and the funds flowing to their projects.
Jeff,
The null theory you have presented here captures succinctly my thoughts as well with the first three paragraphs focusing in on AGW exaggerations. Nothing ruins the truth like stretching it and refuting each new proclamation of doom from the AGW believers is like shooting fish in a barrel.
This letter is very typical of the Liberal Progressive way of getting… their way. Create a crisis, throw some unprovable or patently false ‘facts’ to show how much of a crisis it is, then demand quick, drastic action before the crisis gets out of hand. The quick, drastic action must always involve empowering a few both financially and legislatively at the expense of the many.
It’s also very important that there be no substance to the crisis claims. This way, they’ll get the money, clamp down on the privates – so to speak – and then take credit when nothing happens.
The original letter was written for political purposes; signed by political supporters (and potential political beneficiaries); published for political reasons in a medium not always associated with politics for precisely that reason. All those conditional adjectives in the letter should be the first clue. Attempting to propose computer models as proof of anything other than the models themselves is the second. Referring to “evil politicians” (who, by implication, if alive today might oppose AGW)of a past age when irrelevant is a third.
Just BTW, the reason the Virginia AG’s office is–and should be– looking at Dr. Mann is because of his own stiff-necked refusal to make his data available under FOIA when public money was involved (had he used only his own money, the AG would never have gotten involved). If you go to a junkyard with your own money, salvage enough parts to make a functional vehicle that you then use only on your own property, the state may not have a right to ask if it has brakes or seatbelts. But, if the state has put up a large chunk of the money to buy the parts…. Or if you intend to drive it on the highways….
The stakes involved in the climate discussion are so high, the correct answer has to be to do nothing until there is much more certainty of facts, not just certainty of opinions.
Excellent post, Jeff.
The thing that I find saddest is that such an elite Establishment should stoop so low as to put their name to such a letter.
Oh how the mighty have fallen.
Again, this is overstated. Can someone find a link which shows the percentage of isotopes from CO2 which are presently in the atmosphere from combustible fuel? The last I read, about 30 percent could be attributed to combustion, the rest could have been released from oceans as surface water warmed. However, even the 30 percent could be in error as it’s calculation didn’t take into account some of the short term recycling and re-release from decaying plant material. The amount of contribution by humans is, amazingly enough, also uncertain.
we can calculate, how much CO2 we released.
a single look at a long term plot of CO2 in the earth atmosphere contradicts the idea, that it might be natural.
i assume some of you folks have seen those graphs before?
sod said
sorry, Jeff, but not a single one of your arguments against the 5 main points is convincing in any way. you did just post what was on your mind?
Oh wait, I get it! Jeff was sittin there at his machine when all of a sudden the ….. “climate pixies” yeah that’s it… flew in through the window, probably attracted by the CO2 he was puttin out, and forced his fingers to write that bad bad stuff just so that Sod, in all his magnificence, could come and, so skillfully and with razor sharp intellect, slay Jeff’s arguments with but two small sentences.
Do I win a prize?
Oh wait, I get it! Jeff was sittin there at his machine when all of a sudden the ….. “climate pixies” yeah that’s it… flew in through the window, probably attracted by the CO2 he was puttin out, and forced his fingers to write that bad bad stuff just so that Sod, in all his magnificence, could come and, so skillfully and with razor sharp intellect, slay Jeff’s arguments with but two small sentences.
Do I win a prize?
Jeff occasionally writes stuff that makes sense. this post doesn t.
why not simply explain the current rise of CO2 to me?
Again….this letter is nothing more than yet another pathetic plea for MONEY and ATTENTION by the Global Warming Industry, Inc. After all, their industry runs on money (especially other people’s tax money), which helps fund their trips to Bali and Cancun. And they don’t even have to provide anything useful in return…what a great industry to work in!
Let me know when they can forecast next year’s climate…
Sod: The relationship of temperature to CO2 levels simply puts the lie to your point. CO2 levels trail, not lead, the temperature increases. And what about the MWP?
Sorry to rain on your parade, but if you had read the open letter more assiduously, you would have noticed that the prospect of a fortune was related to anyone who could successfully challenge the theory of gravity or evolution, not global warming. However, these theories were mentioned quite deliberately in order to suggest that agw was on the same fairly firm ground. This suggestion is of course without merit. In my opinion, the composer of this open letter has done nothing to promote his cause other than the usual appeal to authority, not even thinly disguised. There is something familiar about the use of black and white logic used in this letter which gives it religious overtones. It is badly written. I feel sorry for the signatories whom i am certain were instructed to affix their signatures in a sad attempt to give the work some credibility.
Not one of the signatories is a climate scientist.
The background and expertise of the signatories is quite hm varied. Temporarily, the working document is here.
#17 right after the statement about other conclusions, the letter said,
Climate change now falls into this category
It seemed like enough of a similarity.
I use my daughters old email to try to get a comment in at Tammy’s site. It worked. They were picking on Monckton’s credentials, and his statement about the CO2 rise being linear vs exponential.
Post quote:
“Anne
If they confronted this fake lord with the facts, like in this New Republic article by Al Gore, he would wilt!!!!”
http://www.tnr.com/article/politics/the-crisis-comes-ashore
That New Republic piece is a piece of work.
Not surprisingly, Grant Foster accepted the comment, what a one-sided warm-pusher he is .
Hal
Joe McCarthy was right.
Ironic isn’t it.
Sod says:
why not simply explain the current rise of CO2 to me?
A relatively simple task once we have enough data to the required degree of accuracy. Which is the problem. What ya got?
I do agree with sod. The majority of CO2 in the atmosphere is related to human activities. Not all of that is from emissions, some of the rest is from land-usage changes and cement manufacturing. I believe the amount from CO2 dissolution of ocean water is relatively small, but I don’t recall the percentages.
But Sod..perhaps instead of just being snarky, you could post the actual numbers?
#23, First, I think you mean the majority of the increase in CO2. It’s been too long but I read an article that attributed like 30 percent of atmospheric CO2 increase to emission and the rest to warming release from oceans – it was not a skeptic paper.
In an AGW scenario, we know that a substantial fraction of the atmospheric CO2 increase will come from ocean warming.
The letter is basically the reaction you would expect. Kinda like animals defending their territory, when threatened, or the perception of a threat, they overreact immediately.
And there was whining and gnashing of teeth…
Sod.. you do realize that the ice core graph you linked to proves that temperature drives co2 and not the other way around… right? On average of 800 years. This one of those truths that get ignored in this debate.
Jeff, thanks. You’re correct. The “majority of the increase since 1850” is I believe the correct statement.
I’d be interested in your article, if you could find one.
Again, my comment was more aimed at Sod. A challenge for him to substantiate his comment with real-world numbers and technical links.
#26
I find the lag of 800 years, in regard to CO2 vs temperature a significant dis-similarity to the current situation. I also find the current timespan of decades, vs 1000s of years, notably dissimilar. Do you?
If so what do you make of the AGW idea that the two are inter-twined, and that rising temperatures cause the oceans to cough up CO2? And that trapped methane will be released at an increasing rate, thus increasing temperatures?
Thoughtful Tom:
I agree. We are talking about a very short-period injection of CO2, possibly doubling it’s value over 100 years. We know that CO2 acts as a feedback, the 800 year lag data points to that (warming causing CO2 dissolution, increasing the temperature even more), that’s all this really shows.
It doesn’t tells us much about what happens when CO2 acts as a forcing (unless you look at geological periods when CO2 led rather than lagged temperature change).
Bob Grumbine has some numbers here . Typical Maoist propaganda.
The renowned “National Academy of Scientists” could only gather 250 signatories for their declaration. While counting heads or votes in science has zero significance, one wonders why so few signed up.
Could it be that most of the real scientists had already signed up with the “Oregon Project”. I am a scientist and that is the declaration I signed along with 30,000 others:
http://www.oism.org/pproject/
28-
As you yourself said, the timescale is different. The idea about that has zero relevance for AGW.
This ought to be view as the biggest load of shit that the promoters of alarm are selling. Just look at what Methane has done lately, it’s increasing at a slower and slower rate year after year. How can continual warming be causing more and more methane to be released causing more warming if methane is increasing ever more slowly?
#23, First, I think you mean the majority of the increase in CO2. It’s been too long but I read an article that attributed like 30 percent of atmospheric CO2 increase to emission and the rest to warming release from oceans – it was not a skeptic paper.
In an AGW scenario, we know that a substantial fraction of the atmospheric CO2 increase will come from ocean warming.
so if you follow that idea, you will have to search for the biggest increase in ocean temperature over the last 400000 years.
the “CO2 increase was not manmade” story simply doesn t make any sense.
—————-
the time lag of 800 years has been discussed countless times. it doesn t support Jeff’s statement. because it gives us a pretty good idea, at what time we should look for a massive warming event. but none of those happened 800 years ago.
(the “MWP” is one of the small wiggles in that blue line)
———————
Could it be that most of the real scientists had already signed up with the “Oregon Project”. I am a scientist and that is the declaration I signed along with 30,000 others:
most people on that list don t even have a PhD. the comparison with those NAS scientists is a bizarre move.
33 Sod
I don’t have a Ph.D. for reasons that have nothing to do with my intelligence or capability. In fact, the school of hard knocks for 3-4 years in the younger era can be competitively educational with a Ph.D.
There have been many times when this discussion about climate seems to pit Ph.D.s behind computers against Masters at the coalface. Decades ago I would have opined that it did not matter, it was just one more level on the ladder of learning. Now, it seems, the failure to take that extra step up the ladder can be a reflection on the way that groups of people think. Some prefer not to go to Ph.D. beause it’s too theoretical and they prefer applied. Others might know thay are not good teachers and so choose not to head that way. Etc, etc.
It would take a brave person indeed to attempt an analysis of performance traits of each group of qulaifications (not the least because most of us have friends in both groups). To me, the most important factor is the ability to understand and to apply the scientific method, including reporting failures as well as what seems to be new ground at the time. The scientific method does not require the higher degree for comprehension of the method; indeed, in some cases it can lead to over-specialisation to the point of being ineffectual.
Right or wrong, my feeling is that the majority of writers here are either older Masters types or retired Ph.D. professorial types with the wit to see the failures of the keen young highly qualifieds. In summary, good people to review papers and give them breadth of experience. But, be assured that I’m not knocking either level of attainment.
There have been many times when this discussion about climate seems to pit Ph.D.s behind computers against Masters at the coalface. Decades ago I would have opined that it did not matter, it was just one more level on the ladder of learning. Now, it seems, the failure to take that extra step up the ladder can be a reflection on the way that groups of people think. Some prefer not to go to Ph.D. beause it’s too theoretical and they prefer applied. Others might know thay are not good teachers and so choose not to head that way. Etc, etc.
even IF all of that is true, your argument has a massive problem: it is the people with a PhD+ education, that do the scientific research.
your argument would be the same, if you said that sports commentators tend to be quite witty folks. why not just listen to them?
Right or wrong, my feeling is that the majority of writers here are either older Masters types or retired Ph.D. professorial types with the wit to see the failures of the keen young highly qualifieds. In summary, good people to review papers and give them breadth of experience. But, be assured that I’m not knocking either level of attainment.
the “keen young” in the NAS? errors don t get much bigger than that!
wiki gives an average age of 70 for those in the NAE.
http://en.wikipedia.org/wiki/National_Academy_of_Engineering
things will be similar in the NAS, though in 1945 tehy were quite “young” with 50 average…
http://www.jstor.org/pss/87701
Hi Sod
Your post #33
I ran a long thread here on CO2. There are numerous links to a variety of articles, and whatever your views I think you would find it interesting to read my article, the links and the comments;
https://noconsensus.wordpress.com/2010/03/06/historic-variations-in-co2-measurements/
You are making a large number of assertions which are controversial to some here, but lets home in on the more interesting aspects. These boil down to how long and how warm does a warm period need to be in order to release signifcant amounts of Carbon from the oceans? How long does it take for cause and effect to happen?
Personally I don’t believe the 800 year lag scenario, I think it is much quicker, but an extended warm period would cause that warmth to spread further into the deep ocean and it may well be that takes a considerable time before it manifests itself as Co2. However, I think shorter periods of warmth will have a noticeable effect on the upper ocean levels that will be much quicker to become apparent with a release of co2.
If you need a ‘massive warming’ event to suopport a hypothesis I think these are not evident in a geologically recent time scale. However if you just need a warm event lasting some years, there are many examples of this. The most famous is the period covering the decades 1690 to 1730 when temperatures rose much quicker and further than they have done in recent years.
So I would be interested to hear your thoughts as to how long and how warm a period needs to be before the ocean reacts, and also your estimation of the time lag involved.
Tonyb
Sod,
You should retract your insinuation that the 9000+ PhDs who signed the global warming petition project are somehow inferior to the 250 “scientists” who signed the letter highlighted by Jeff.
I suggest you google some of the 250 signatories to the letter as regards to their ages, qualifications, and areas of expertise before you make any more blanket assertions, unsubstantiated claims and ad hominem attacks on this forum. You will find that “climate scientists” are thin on the ground amongst them, and that most of them aren’t geriatrics. In addition even you must be able to recognise that 250 falls massively short of 9029…
I ran a long thread here on CO2. There are numerous links to a variety of articles, and whatever your views I think you would find it interesting to read my article, the links and the comments;
your argument is based on wild fluctuations of CO2, like assumed by Beck. the basis of your argument is false. stuff that you conclude from a false base, can be either false or true. in this case, it is false as well.
However if you just need a warm event lasting some years, there are many examples of this. The most famous is the period covering the decades 1690 to 1730 when temperatures rose much quicker and further than they have done in recent years.
this claim, again, is false. for example the Loehle graph does not support your claim about a temperature high in that period.
even if your claim was true, you would still need to explain, why such a spike never happened before, over 400000 years. good luck.
I suggest you google some of the 250 signatories to the letter as regards to their ages, qualifications, and areas of expertise before you make any more blanket assertions, unsubstantiated claims and ad hominem attacks on this forum.
as always, i did not make any ad hom attacks. it is getting a little boring, to argue with people who don t understand those fallacies. but constantly insist in using them in their posts.
if you think that the NAS is made up of people, who can be described as “keen young”, then you will have some evidence, don t you?
they are all respected scientists. they understand enough, to sign that petition. there is a lot of climate related expertise among them.
somebody above posted a link. just take a look.
Click to access signatories.pdf
You will find that “climate scientists” are thin on the ground amongst them, and that most of them aren’t geriatrics.
“climate scientists” are thin among them, because there will be few of them among any group of scientists. i did not argue that they are geriatrics, i just contradicted the claim that they were young and keen with EVIDENCE. if you think that you can counter my claim, bring on the links!
In addition even you must be able to recognise that 250 falls massively short of 9029…
getting 10% of such a highly respected group to sign a petition fast, is quite an achievement. your comparisons with random online polls don t make any sense.
Sod
The speed with which you came back makes it quite evident that you did not do me the courtesy of reading the article, comments and links. My basic proposition was to look at the historic context-not the scientifc one- as to whether the assertions that co2 was accurately measured in that era could be true. You are putting other elements in to the equation that were not part of the thrust of the article and would suggest that if you read everything you will find many cogent arguments from both sides of the fence.
Moberg missed the warmth as well in the period cited, but is is extremely well documemted by instruments as well as observations made at the time.
You still haven’t answered my questions summarised here
” So I would be interested to hear your thoughts as to how long and how warm a period needs to be before the ocean reacts, and also your estimation of the time lag involved”.
Tonyb
The speed with which you came back makes it quite evident that you did not do me the courtesy of reading the article, comments and links
sorry, but if you want people to read your stuff, don t start with a reference to Beck.
i read some further comments after i posted my reply, and they confirm my position.
” So I would be interested to hear your thoughts as to how long and how warm a period needs to be before the ocean reacts, and also your estimation of the time lag involved”.
my assessment of this would be irrelevant. but IF short time temperature highs would produce spikes like the current one in the sea ice cores, then we would see such spikes in the past record. we don t.
so if your 50 years period produced the current spike, then it was the first of that kind in 400000 year. and needs some explanation itself!
and the Loehle reconstruction doesn t show any spike at all.
you are basing your “theory” on multiple claims (CO2 spikes, temperature spike around 1700) which are obviously false.
it doesn t make any sense to discuss the rest of your posts, before you correct those obvious errors.
Sod
Again it is evident you have not read the article or the links and comments and you are putting words in my mouth. Where did I refer to a spike? I said this;
“If you need a ‘massive warming’ event to suopport a hypothesis I think these are not evident in a geologically recent time scale. However if you just need a warm event lasting some years, there are many examples of this. The most famous is the period covering the decades 1690 to 1730 when temperatures rose much quicker and further than they have done in recent years.”
I did not say they rose higher, but ‘quicker and further’. This is cleatrly shown in the graph you referenced which also shows the MWP.
Again I would ask;
“So I would be interested to hear your thoughts as to how long and how warm a period needs to be before the ocean reacts, and also your estimation of the time lag involved.”
If you do not have an opinion of your own perhaps you would cite the succinct answer from someone you believe has the answer.
Tonyb
I did not say they rose higher, but ‘quicker and further’. This is cleatrly shown in the graph you referenced which also shows the MWP.
ahm, you do realise that the Loehle graph ends in 1935?
the 1700 temperature did NOT rise either quicker, nor further.
but again: even IF it had changed “quicker” in that period, you need to explain why CO2 release from the oceans would be based on rate of change, instead on actual temperature.
each of your replies is based on another false assumption.
“So I would be interested to hear your thoughts as to how long and how warm a period needs to be before the ocean reacts, and also your estimation of the time lag involved.”
why< would my guess on this matter? why should i waste the time to search a source?
here is the graph, showing an immense stability of CO2.
the spike at the end of that graph needs a real explanation. a 50 year warm event around 1700 (which actually does NOT exist) can not explain the current spike. this should be not all that complicated to understand.
(so my answer is longer than 50 years, and lag will also be longer than 300 years)
Sod,
Why do you turn this thread to another CO2 – sensitivity thread? Why not discuss the fact that Science published a letter by Peter Gleick and Stephen Schneider in support of Michael Mann?
Any thread in climate can be derailed and corralled into the radiative physics channel. That does not serve any useful purpose.
How interesting, sod. If you disagree with each of Jeff’s points, you have inadvertently given us a statement of your position, an unusual act for someone so unrelentingly negative.
1) There is no exaggeration in climate models. Papers criticising them have not been blocked from publication.
2) The significance of recent warming has not been exaggerated relative to historic natural variation. We do know, accurately, what global temperatures were pre-1900. Proxy measurements are accurate to the level necessary to conclude that this is the warmest period in human history.
3) Massive flooding is likely even though sea levels are increasing at around 3 mm per year. Extreme weather events are becoming more frequent and severe. Violent tipping points are likely although no mechanism has been proposed.
4) You alone understand the atmospheric lifecycle of CO2.
5) In spite of the wide range of predictions of the various models, there is no uncertainty as to the outcome.
Nice to know that you are the defender of science and we are the flat-earthers.
The fake photoshop Polar Bear picture that accompanied the article demonstrates their degree of integrity quite adequately.
(Science may have inserted it rather than the authors but the point is the same regardless).
We do not need any more fake photos, bad math, adjusted data or exaggerations. Facts, by themselves, should be more than enough.
Sod,
Why do you turn this thread to another CO2 – sensitivity thread?
Jeff made a comment, that is simply false. sorry that i contradicted his false claim. i didn t know that pointing out his errors was forbidden. just because the error was pointed out in the past already?
How interesting, sod. If you disagree with each of Jeff’s points, you have inadvertently given us a statement of your position, an unusual act for someone so unrelentingly negative.
i would have signed that letter. those scientists made the decision to sign this, because there is ZERO doubt about those points. i just demonstrated this on one point.
nobody so far came up with any reasonable defence of the claim made by Jeff above. NOBODY!
The fake photoshop Polar Bear picture that accompanied the article demonstrates their degree of integrity quite adequately.
jupp, those NAS scientists who chose that photo are really evil people.
think first. post later!
you are ignoring what they said, and focus on the photo. you are doing exactly the thing, that they mention in the article.
Sod,
I haven’t answered your points, mostly because you will disagree no matter what I write, and partly due to lack of time. But your point did not address my point whatsoever. In fact you’ve completely failed to address the point in any way that I can see except the claim that I made an error. It’s tiring arguing with non-technical troll behavior.
I will attempt to find an article on CO2 increase which shows the percent due to man and the percent due to warming, there are several but I’m feeling a bit lazy. You may find yourself quite alone if you try to claim all CO2 was added entirely by man although if you say most, at least this pile of polyscienticians will agree. If I spend part of my day to dig something up, will you read it?
I haven’t answered your points, mostly because you will disagree no matter what I write, and partly due to lack of time. But your point did not address my point whatsoever. In fact you’ve completely failed to address the point in any way that I can see except the claim that I made an error. It’s tiring arguing with non-technical troll behavior.
my simple point was this: IF warming of the ocean was the major factor in driving the current CO2 high in the atmosphere, then it would need to be a pretty extreme warming. and that warming shouldn t be man-made. (as CO2 added to the atmosphere because man was warming the ocean would also be man-made CO2)
the subject is a little bit complicated. annual CO2 fluctuation is high. a “man-made” CO2 molecule leaving the engine of my car could end up in a plant, just a short time later. while an dying 300 year old tee releases another “natural” CO2 molecule to replace it.
the
sorry something went wrong above..
the NAS statement said:
(ii) Most of the increase in the concentration of these gases over the last century is due to human activities, especially the burning of fossil fuels and deforestation.
not “the source of the majority of additional CO2 molecules in the atmosphere can be tract back to a human source”. and it doesn t make that claim for a reason.
if you think that 70ß% of the additional CO2 comes from natural sources (like from a warming event in the past), then just say so, and point out the event.
oh, and before i forget it:
The fake photoshop Polar Bear picture that accompanied the article demonstrates their degree of integrity quite adequately.
this is a nearly perfect example of an ad-hom attack! photoshop picture next to the article shows that the content of the article is rubbish.
looks like sceptics are pretty good in doing ad-homs, even though they don t understand the concept at all!
Grumbine did not mention the issue of declining oxygen concentrations mentioned here .
Per this source , 64% is due to fossil-fuel combustion, the rest is due to land-use and cement manufacture.
Hi Sod
You appear to be confusing a historical analysis of Co2 measurements with a scientific paper.
I clearly said at the start of my article;.
“Consequently in this article I have endeavoured to look at the little known social aspects of CO2 from the 18th Century onwards, in order to demonstrate that accurately measuring this gas was a common place occurrence and that the historic records appear to show that levels have changed little over the past 200 years. As general background, the British Govt then- as now- liked to regulate industries (in this case setting CO2 levels in factories at 900ppm in 1887) and didn’t tend to stipulate legally binding regulations unless they had the means to measure, enforce, and subsequently fine transgressors”
I cited first of all the conventional co2 graph fromn IPCC and then the historic view. I then give numerous citations from both sides of the fence including someareboojums who are extremely hostile to the idea. I don’t even mention Beck until the last couple of paragraphs of a long article. History tells us that;
* Measuring carbon dioxide was a natural part of life of advanced countries, commencing around 1800 and acquiring an increasing degree of accuracy from 1830.
*There were numerous high quality scientists carrying out the measurements
* Hundreds of thousands of such measurements were made
* Techniques became increasingly accurate and contamination issues recognised.
*Various instruments were patented to measure the concentration.
*The British Govt legislated for maximum concentrations towards the end of the 19th century after discussing the matter for 20 years before that.
Those are the historical facts. Whether you choose to believe the measurements or believe our talented ancestors were incapable of taking a relatively simple reading despite 120 years of trying, is up to you. Many agree with you, but were somewhat more constructive in their comments, having actually read the article before commenting.
As regards the warm period I cite, I am surprised you are unaware of it. Can I respectfully suggest you might find of interest a good climate book from someone like Hubert Lamb- first director of CRu-who spent most of his career carrying out historic research. ‘Climate History and the Modern World’ ISBN 0415127351 would be a good one to start with.
This is my web site where I collect pre 1850 instrumental records from around the world, plus observations and records from a variety of sources. You might enjoy the climate refernces from the Byzantine empuire circa 380 AD to 1450 AD
http://climatereason.com/LittleIceAgeThermometers/
This is a article that refers to a couple of graphs that are from the warm period I mentioned. There is numerous documented information that support the warmth of the time.
http://chiefio.wordpress.com/2009/10/09/how-long-is-a-long-temperature-history/
Of course I know when Loehle finishes his graph-at the end of a very warm period. At least we have an answer from you to my questions, for which I thank you.
Temperatures have been drifting upwards-with some notable warm and cold events intervening – since the 1690 decade to the present day. The most rapid and biggest rise in that entire period was from 1690 to 1730. Since 1810 every decade has been warmer than that decade. Giss and CRU merely plug into the end part of this historic and long lived upwards trend, which as far as I am aware is natural and is now starting to return us towards the levels of the MWP and the Roman Optimum, and the Various Holocene periods including the Bronze age.
Perhaps that extended period of several hundred years is long enough to meet your criteria as to when co2 might be be released from the oceans-or perhaps we need to back track a little further to be within your lag period?
best regards
Tonyb
51.sod said
May 9, 2010 at 11:46 am
I suggest you look up the term “argumentum ad hominem.” Clearly you have never done this. It is not an “attack,” it is an argument in which the character, or some irrelevant personal premiss about the argumenter is used to dismiss his idea. Since the photoshopped picture is in the article as an attempt to exaggerate the importance of the article itself, it is irrelevant.
It is quite clear this statement applies to you more than the skeptic you are attempting to insult.
Mark
55.Mark T said
May 9, 2010 at 12:51 pm
Should be “it is hardly irrelevant.
Mark
I cited first of all the conventional co2 graph fromn IPCC and then the historic view. I then give numerous citations from both sides of the fence including someareboojums who are extremely hostile to the idea. I don’t even mention Beck until the last couple of paragraphs of a long article.
the second graph is labeled with his name: Beck 2009.
https://noconsensus.wordpress.com/2010/03/06/historic-variations-in-co2-measurements/
if you want to make reasonable people read your article, you shouldn t do that.
As regards the warm period I cite, I am surprised you are unaware of it.
so it is a warm period now? your last claim was :I did not say they rose higher, but ‘quicker and further’.
the chifio (oh my god) article you link to, also doesn t show a special warm period around 1700.
———————
my simple question remains: will faster warming release more CO2 than a slow one? based on what mechanism?
Hi Sod
I did not label the graph-are you suggesting I should remove the authors own small reference in the bottom right hand corner so as not to scare people?
It is a warm period in as much it is warmer than the ice age conditions that preceded it and warmer than many of the decades that followed it. Why is that inconsistent with my comment;
‘I did not say they rose higher, but ‘quicker and further’.
You are playing with semantics.
The ‘special warm period’ is the one much warmer than the one that preceded it Sod, and in the case of Uppsalla the one that is very similar to todays values.
You seem to be in the same time zone as me Sod-are you from England or just staying up very late elsewhere 🙂
best regards
Tonyb
The problem, Tonyb, is that you used the word have instead of had. Your original quote was
rose much quicker and further than they have done in recent years.
which tends to imply a time period relative to now, rather than relative to the 1700 period in which you were referencing. Had you replaced the word have with had, it would have been much more obvious, even to someone of sod’s intellect. I understood your claim, and looking at the graph, it seems legitimate.
Sod, of course, cannot enter an argument without committing the very fallacies he accuses others of yet understands so poorly himself. Note, too, that he left off the part of your original statement “than they have (had, sic) done in recent years” which makes his point that much more convincing. Leaving that part on, the first question in a rational argument would have been “did you mean had, not have?” This is a strawman argument, sod, another of the many fallacies you commit. Further education is definitely required on your part, but I suppose if you did that, then you’d have to be a liar to continue the rants you so often put forth.
Mark
Jeff:
My suggestion is don’t cherry pick the literature to find the one place where you get agreement with your perception of the facts. RB’s links (especially #52) are useful if what you are interested in are the facts.
Yes there are warts in the data, but if you really want to understand the issues, you should start by reading up on Keeling and his contributions. This is a good starting point.
He basically revolutionized how CO2 was measured, and our understanding of the various processes that produce variations within it. Prior to him, it wasn’t generally understood just how large the potential confounds were… if you want to look at pre-1950 data for example, you can’t treat all of the data as if they had equal weight. In measurements in a city around 1900, you might easily find nighttime values of 500 ppm for example (assuming a nocturnal inversion).
Keeling and coworkers set up a series of locations for measuring CO2 levels. There is a compendium of data taken here. This also includes the important C13/C12 and C14/C12 measurements.
While I”m not saying you can’t use data collected before Keeling, you just need to use what he learned to inform on how it is done. But I am saying there are major issues if you are trying to use these early data to estimate global CO2 concentration level without factoring in the metadata associated with them.
In my opinion, one can safely state that CO2 has increased from 1850 to current from roughly 270 ppm to it’ current value around 385 ppm. One can also safely say that the “majority” of this CO2 is anthropogenic in origin.
There are legitimate issues one can raise with that letter, but this part of the “basic science” part is I think on pretty firm grounds.
Carrick,
I’ve spent quite a few hours perusing papers and data on this, it’s not my first dance despite my lack of references. I’m mostly interested in the isotope ratios and airborne lifespan because I just don’t believe the 1000 year residence time but haven’t run any calculations myself. There is quite a bit of disagreement on CO2 residence time.
I’ll check rb’s links.
Carrick,
RB’s link is silly. it assumes that CO2 hasn’t changed for centuries, and then goes from there calculating the weight of CO2 in the atmosphere and the weight emitted. It completely ignores the fact that the carbon sink has increased each year, that 30 year fluctuations in historic records would be filtered by the non-closed cells in snow before it’s packed into ice cores. This is not a good number.
———–
A. Anthropogenic CO2 comes from fossil fuel combustion, changes in land use (e.g., forest clearing), and cement manufacture. Houghton and Hackler have estimated land-use changes from 1850-2000, so it is convenient to use 1850 as our starting point for the following discussion. Atmospheric CO2 concentrations had not changed appreciably over the preceding 850 years (IPCC; The Scientific Basis) so it may be safely assumed that they would not have changed appreciably in the 150 years from 1850 to 2000 in the absence of human intervention.
In the following calculations, we will express atmospheric concentrations of CO2 in units of parts per million by volume (ppmv). Each ppmv represents 2.13 X1015 grams, or 2.13 petagrams of carbon (PgC) in the atmosphere. According to Houghton and Hackler, land-use changes from 1850-2000 resulted in a net transfer of 154 PgC to the atmosphere. During that same period, 282 PgC were released by combustion of fossil fuels, and 5.5 additional PgC were released to the atmosphere from cement manufacture. This adds up to 154 + 282 + 5.5 = 441.5 PgC, of which 282/444.1 = 64% is due to fossil-fuel combustion.
Atmospheric CO2 concentrations rose from 288 ppmv in 1850 to 369.5 ppmv in 2000, for an increase of 81.5 ppmv, or 174 PgC. In other words, about 40% (174/441.5) of the additional carbon has remained in the atmosphere, while the remaining 60% has been transferred to the oceans and terrestrial biosphere.
The 369.5 ppmv of carbon in the atmosphere, in the form of CO2, translates into 787 PgC, of which 174 PgC has been added since 1850. From the second paragraph above, we see that 64% of that 174 PgC, or 111 PgC, can be attributed to fossil-fuel combustion. This represents about 14% (111/787) of the carbon in the atmosphere in the form of CO2.
I wouldn’t ever claim that Man has not affected CO2 levels at all, we release a lot, what I’m interested in is how long it remains resident and in my statement above whether emissions comprise the majority of the measured change. The only way to answer these questions is through changes in isotope concentrations.
I strongly disagree with the ‘conclusions’ in this letter, but again, I’ve already given my opinion.
Jeff ID, here’s my take on this…
a) Start with the data not the conclusions. That’s why I linked the raw data sources. As I mentioned this includes the isotopic ratio measurements.
b) Understand the contributions that Keeling made to the field, and you’ll get a much better feel about “appropriate” and “inappropriate” uses of the data.
c) If you’re going to use old data to set numbers, understand the limitations of their knowledge about how to make accurate assays of mean atmospheric CO2.
I’m not sure what the real persistence level of CO2 is, that is injected into the atmosphere as we have done. 1000 years sounds like a hairball number to me. I think the real number is much smaller (maybe 50 years).
From my perspectives here are some problems with the letter and its conclusions:
MarkT
Yes, you are possibly right. I blame lack of sleep since stsying up all night for the election. Let us be charitable to Sod and asume he is British and had the same experience too. 🙂
tonyb
Jeff, I think you could work out the persistence time of CO2 by looking at the ratio of sinks to sources and the question of why that is remaining constant even with this rapid increase in rate of emissions.
At this point, I don’t think the science can really say what would happen if our CO2 emissions leveled off. (One common alarmist tactic is to conflate “could happen potentially” or “can’t be excluded” with “most likely scenario”).
tonyb said
May 9, 2010 at 2:27 pm
Sod is a rather well known troll and he has clearly demonstrated over the years a lack of interest in the truth, whatever it may be, except if it agrees with the current dogma. There’s no reason to be charitable to this kind, ever.
Mark
I did not label the graph-are you suggesting I should remove the authors own small reference in the bottom right hand corner so as not to scare people?
no, just don t quote and use them, if you want to be read by reasonable people.
It is a warm period in as much it is warmer than the ice age conditions that preceded it and warmer than many of the decades that followed it. Why is that inconsistent with my comment;
‘I did not say they rose higher, but ‘quicker and further’.
You are playing with semantics.
this is not semantics. you implied that a faster increase would be different. it isn t.
again: to explain the all times high in CO2 by temperature, you are looking for a very high temperature in the historic record. the period you named, is not high.
rose much quicker and further than they have done in recent years.
which tends to imply a time period relative to now, rather than relative to the 1700 period in which you were referencing. Had you replaced the word have with had, it would have been much more obvious, even to someone of sod’s intellect. I understood your claim, and looking at the graph, it seems legitimate.
no Mark. the real problem is, that he used a period, that is not special in other datasets. he cherry picked a period, and now uses it to make wild claims. and he is confused about quick temperature rises. and he didn t realise, that the Loehle graph is not up till now.
simply too many errors, for such a short time.
———————–
I wouldn’t ever claim that Man has not affected CO2 levels at all, we release a lot, what I’m interested in is how long it remains resident and in my statement above whether emissions comprise the majority of the measured change. The only way to answer these questions is through changes in isotope concentrations.
this is false. if you think that a ocean temperature increase caused the recent rise in CO2, then you need to name the event.
ratios could stay completely stable, if the fluctuation is high enough. (they aren t, as most sources show, supporting the human source of the CO2. but they could.)
without a temperature event, you can t use it as an explanation. you brought up a weak argument. why not simply admit it, and move on? (shifting the discussion to residency times is just another attempt to obscure your error)
Sod,
I promise there is no attempt to obscure anything. I make plenty of errors. In my humble opinion there are many sources of CO2 which are poorly quantified and the fact that despite ever higher output, the percent absorption/yr remains the same. The only way to isolate the different source vs sink that I can think of is by isotope concentration analysis. What change would you expect from human activity vs what you got.
I’ve read several studies which show that the anthropogenic contributions are very low – 5%, I think the error in these may have to do with total CO2 in play. I’ve also read that CO2 stays resident for thousands of years, I flatly don’t believe that. It’s an incredibly ignorant assumption in my opinion, but I’ve proven nothing. Neither has the IPCC and they rely on the ‘guess’.
Carrick,
I’ll keep reading. Lot’s to learn, not enough time.
Sod
Quite how you write a piece on Historic variations in CO2 without showing what the historic levels are seems something of a conundrum Sod. Surely people are perfectly capable of seeing a tiny little name in the bottom of one graph without falling in to a faint even if;
a) they noticed it
b) they had ever heard of Beck in the first place.
I think you may be conflating two separate dicussions when you say:
“again: to explain the all times high in CO2 by temperature, you are looking for a very high temperature in the historic record. the period you named, is not high.”
There is no CO2 measurement for that particular warm period so I am not claiming anything at all of the sort related to that discussion.
That it was a warm period compared to what had preceded it for at least 50 years, and what suceeded it for an even longer period, surely must by any defintion mean that it is a warm period. I am not saying it was the highest ever recorded, but that it was very warm by those criteria. This is contained in the instrumental and other records. It is a matter of verifiable fact and not cherry picking.
I am sure you will enjoy the climate book I recommended Sod, as it will help to put past climate episodes into context.
AS for Loehle I have had many discussions concerning his graph. I dont know why you need to believe I dont know what period it covers.
tonyb
I’d also recommend a good book on logic for sod, Tonyb, since sod clearly has never studied the topic. I’d personally recommend fallacyfiles.org, but I’m quite certain either recommendation falls on deaf ears as sod neither wishes, nor is capable of learning.
No he didn’t. He used a period in which there was a sharp rise that went above the little blip that had occurred within the previous century, exactly as he had stated.
I’d also recommend you learn the use of the comma, though I must admit that seems to be a problem endemic to society as a whole. The difference, however, is that you are claiming some greater intelligence while failing to demonstrate that you actually possess such a thing.
I noticed you have not apologized for your insults that were based on a false understanding of the concept of an argumentum ad hominem. I wonder if that makes you dishonest, or just an idiot. When I refer to you as a hypocrite as well, it’s just an insult, not an argumentum ad hominem, though one based on fact so there’s no reason for me to offer an apology.
Mark
Tonyb, my problem is with how some people treat the historical data (all values equal), Beck is in this club, is they appear to show no awareness of the impact of an urban environment on local CO2 levels.
Phoenix is a good illustration of what can happen:
Annual Variation of CO2, year 2000, Phoenix, AZ
Idso, 2002
Vertical profile of CO2 above Phoenix
Bailing, 2002
I think after Keeling started taking high temporal resolution data and realized e.g. there was a diurnal effect in the atmospheric boundary layer that this drove some major changes in practices for sampling atmospheric CO2 concentration. Anything prior to 1950 in terms of direct measurements is IMO suspect.
“sod neither wishes” should be “sod neither wishes to learn” followed by the rest.
Mark
#66 Carrick, some studies indicate that airborne fraction has a lag time for achieving steady state and could be O(50 years) for exponential emission growth rate. This particular study also presents good agreement of the C4MIP models with carbon cycle modeling and observations in Figure 2 and postulates that airborne fraction is dependent on emissions growth rate. Based on this, it is not obvious to me that the airborne fraction offers a means to say that the claim of a fraction of emissions having a long residence time is false, if that is what you were implying.
Carrick
I don’t wish to hijack Jeffs thread as I had a very good run with my own, so will conclude with these comments.
I am not a mouth piece for Beck-I am primarily interested in examining the historical background to the development of CO2 readings and put it into a broader social context. In this regard I became interested in the subject several years ago and researched information without -at that time- even knowing about Beck.
I quickly came across his work of course and deliberately kept clear of his accumulated research in order not to be influenced by it. That was not hard to do as my area of interest was not the same as his.
Eventually, after I had come to my own conclusions that CO2 measurement was a well travelled and well understood road- certainly by 1850 or so- I looked at his information.
Suffice to say that I think that Beck was rather naive with the way he initially presented the information he gathered, but there is a lot of interesting material there, a proportion of which appears to have some merit.
Bear in mind that our ancestors were innovators of 120 years of startling scientific progress from 1830 to 1957- when Keeling started his measurements- were more than capable of determining a relatively simple calculation, and knew what should or shouldn’t be excluded as potential contaminats of the results, such as an urban environment.
In view of what I found out 2 years ago, what I learned when writing the article, and subsequently examining Becks comprehesive information, I would say that I have sufficient doubts (not certainties) about the modern Co2 storyline to believe that a genuinely independent audit of the ‘old’ co2 records would be appropriate.
That such vitriol is continually heaped on this mainstay of the science by such as Sod makes me suspect that ‘they’ are not as confident of the ice core interpretation (primarily)as they like to assert.
Tonyb
Oops. Sorry. I changed the paper’s name and didn’t update the link: it’s here.
# 37 tertius said
May 9, 2010 at 4:35 am
“I suggest you google some of the 250 signatories to the letter as regards to their ages, qualifications, and areas of expertise before you make any more blanket assertions, unsubstantiated claims and ad hominem attacks on this forum.”
I compiled that on the this link above (work in progress), so that you don’t have to waste too much time. Anyway, the Guardian has the link list.
RB, nice reference. Thanks.
I like these simple models… this looks like a variant on the 2-box model of Tamino/Lucia/Nick/others.
Figure 4 of that figure is the place to start. You could view it as a tunable parameter of the model.
If you know “lambda” (we do) and you know the fraction Af, you tune the model to give the right Af for a given lambda, and you use that tuned model to yield a prediction for the lifetime of the excess CO2 in the atmosphere.
Tonyb:
I have to disagree. The biggest thing was the development of micrometerology and the understanding of the existence and structure of the atmospheric boundary layer.
There is actually quite a bit they didn’t know about this, that was relevant here (e.g.., issues like inversions and turbulent mixing). It owes it’s origin to Taylor, von Karman, Kolmogorov and many others, with the original self-similarity theory of the atmospheric boundary layer (Monin-Obhukov) wasn’t even developed until the 1950s. Keeling didn’t start a revolution on his own, but his measurements of diurnal CO2 variability and associated diffusion processes were an important step forward in micrometeorology, and peripherally, but important to us, how to collect measurements of CO2 that accurately reflect the atmosphere above the ABL.
I am simply suggesting it is important to look at these old data and how they were collected from modern eyes.
When you see CO2 concentration levels in the 400s from measurements in the 1800s, one’s immediate instinct should not be “these people were more than capable of determining a relatively simple calculation.” Whether they could make a simple calculation isn’t even the point. It’s a major “whiff” in fact. The issue is the conditions under which the measurements get taken, and the recognition of the importance of siting of the measurement, and the influence of regional scale anthropogenic activity on the measurements.
Why do you suppose the data were more variable before Keeling?
In one of his rare technical posts, Tim Lambert gets this part right. (Not the snark level, we know we are mostly dealing with little children on the AGW side who are utterly incapable of behaving like adults, e.g., programmers, but that’s an issue for another thread.)
Carrick
Thanks for your excellent reply.
“I am simply suggesting it is important to look at these old data and how they were collected from modern eyes.”
I agree. We must compare like for like, but this has not been done in any meaningful way.
It is not unreasonable to comment that there are old measurements that appear to have a good level of competence and also that our ancestors were aware that certain circumstances affected readings. (The presence of gas burning lights in a factory or the urban nature of an environment was understood.)
The circumstances and competences involved would suggest that a proportion of the measurements obtained might have some merit and consequently would warrant a proper independent audit being carried out.
This audit may indeed completely agree with what you are saying, but until that is done the HISTORICAL record shows that taking CO2 measurements was an increasingly common practice, and that the people involved were perfctly capable scientists. That they may have got it very wrong SCIENTIFICALLY is of course possible, but at this stage no one can say either way for certain.
This sort of audit needs to go hand in hand with the opposite side of the coin which is an examination of the information that corroborates modern readings and its relative constancy, of which ice cores are a major plank.
Perhaps Jeff could get someone like Jonathan Drake to do a post on this latter aspect? (If Jeff is reading this I do have contacts with him, would you like me to ask?)
I am not dogmatic about this subject, as unlike Dr Beck I have not invested a large part of my recent life in this aspect of climate change. There are sufficient questions however to lead me to believe that the older readings have been sidelined (for whatever reasons) and they merit a re-examination.
If Co2 WAS constant, yet we had such large flctuations in our climate in the past, it raises even more questions for me as to its role as a major climate driver.
Tonyb
Sod pontificates:
“as always, i did not make any ad hom attacks. it is getting a little boring, to argue with people who don t understand those fallacies. but constantly insist in using them in their posts.”
Give us a break, Sod, You are a master of the ad hominem.
Above you post this classic example:
“the second graph is labeled with his name: Beck 2009…
if you want to make reasonable people read your article, you shouldn t do that. (#39)
sorry, but if you want people to read your stuff, don t start with a reference to Beck.(#41)
…just don t quote and use them, if you want to be read by reasonable people.” (#68)
And this one:
“the chifio (oh my god) article you link to, also doesn t show a special warm period around 1700”.
And please, get over “smug”, “superior” and” self righteous” and bone up on “humility”, “respect” and “dialogue”.
TonyB: If you take the old data literally (and knowing what we now know about the ABL that they didn’t), that would suggest a very rapid increase and decrease in CO2 over very short periods of time. We’re talking hundreds of billions of tons of CO2 emitted and absorbed in a single year. Where is the source for those enormous injections and rapid sinks? Can you even propose a realistic mechanism that could be responsible for this???
…
And then this all of a sudden stops happening when Keeling started making measurements using instrument sitings (and measurement times) that minimize the effect of urban contamination.
I’m sorry, it’s much easier to explain the high values as being contamination by nearby urban environments. You can claim if you want these scientists were “competent” and therefore could anticipate atmospheric transport effects that weren’t understood till 100 years in the future.
But I’m afraid I don’t buy this, and I don’t know why anybody should. Basically if you want to use the data you need to demonstrate that the circumstances under which they were measured would not have resulted in urban contamination. And you have to develop a plausible scenario by which the atmosphere could gain and lose enormous amounts of CO2 mass in a single year. And finally you have to explain why, after methods that addressed the recent discovers of the influence of the state of the ABL on the transport of CO2 were put in place, this variability in the data suddenly dropped so much. Where did those sources go?
This looks like a pretty steep slope to me.
I think a combination of the Antarctic ice core data plus the Antarctic flask data is as “good as it gets”, and these show none of the rapid fluctuations shown in that historical graph.
Figure.
That last figure is related to this figure by the way. (GDP is a proxy for anthropogenic CO2 emissions.)
Carrick is right.
Carrick
Thanks for your consecutive posts.
As I say I am not dogmatic about this, historically it is certain that competent people took numerous measuremnts and it is necessary to determine scientifically how many-if any- stand proper scrutiny.
Various people have cited possibilities of sinks and sources and contributed a great deal of information both for and against the scientific merits of our ancestors readings. As a result that thread has become a considerable compendium of information from all sides.
Could I ask you to post your 82/83 in the thread so it is all kept together? Thank you.
https://noconsensus.wordpress.com/2010/03/06/historic-variations-in-co2-measurements/
Can I return to my final comment and ask if in your view a constancy of co2 during highly variable climatic periods enhances or reduces its likelihood of being a prime climate driver?
tonyb
Tonyb:
I’m certain it’s an important driver (forcing) as well as an important feedback.
If you read what I’ve said in the past though, there isn’t a linear relationship between CO2 and global mean temperature, the effect of climate on global mean temperature is more complex than just the turning of a thermostat up or down. And that is partly because it can either be a (parametric) forcing or a positive feedback (it amplifies the effect of natural climate forcings).
To this point in history, it has not played a dominant role in global warming. Partly this is because (it is thought) that anthropogenic sulfate emissions prior to circa 1980 nearly balanced the anthropogenic CO2 emissions (sulfates are a negative forcing of course), and partly because it isn’t really a huge effect anyway, compared to natural climate fluctuations. As James Hansen would say, increasing CO2 “loads the dice” of climate variability towards warmer temperatures. It behaves more like a increase in gain than a simple offset if you want an electrical circuit equivalent.
69.Jeff Id said
May 9, 2010 at 4:17 pm
Jeff, the main problem for understanding how much of the increase of CO2 in the atmosphere is man-made, is that many people don’t see the difference between residence time of a single CO2 molecule, whatever the source, in the atmosphere (which is about 5 years) and the excess CO2 decay time (which is about 40 years).
Consider a one-shot injection of 100 GtC fossil CO2 into the pre-industrial atmosphere: that immediately increases the total amount of CO2 in the atmosphere with 100 GtC, thus 100% of the increase is man-made, but that is only 15% of the total mass. As every year some 150 GtC CO2 is exchanged between the atmosphere and oceans/vegetation, the percentage of “man-made” CO2 sinks rapidly to below 1% within 40 years, while the total CO2 mass still is 50 GtC above the pre-industrial level. Thus still the full excess in total CO2 mass is of man-made origin, even if most of the original man-made molecules were exchanged by “natural” CO2 molecules… Here a graph which shows that:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/fract_level_pulse.jpg where FA is the human fraction in the atmospheric CO2, FL in the upper oceans, tCA total CO2 in the atmosphere and nCA total “natural” CO2 in the atmosphere.
Despite that many natural CO2 cycle processes are not linear in any way, the total of all processes is surprisingly linear with temperature, even over thousands of years, as seen in the Vostok ice core: about 8 ppmv/K (see: http://www.ferdinand-engelbeen.be/klimaat/klim_img/Vostok_trends.gif ). Thus the temperature increase since the LIA (maximum 1 K) is only responsible for maximum 8 ppmv of the 100+ ppmv CO2 increase. All the rest is man-made. That also follows from a lot of other items: d13C and d14C decreases in atmosphere and upper oceans, increase of DIC (inorganic carbon) in the upper oceans and last but not least the mass balance: if you add 8 GtC per year and only find an increase of 4 GtC per year in the atmosphere, that means that nature as a whole is a net sink for CO2, not a source…
See further: http://www.ferdinand-engelbeen.be/klimaat/co2_measurements.html#The_mass_balance
#87, for context, part of what Jeff vehemently objects to is that models assume nonlinear CO2 update kinetics (not the linear kinetics that you assume for a 40-year decay time), as described in this publication by Archer :
There are rival definitions of a lifetime for anthropogenic
CO2. One is the average amount of time that individual carbon atoms spend in the atmosphere
before they are removed, by uptake into the ocean or the terrestrial biosphere. Another is the
amount of time it takes until the CO2 concentration in the air recovers substantially toward its
original concentration. The difference between the two definitions is that exchange of carbon
between the atmosphere and other reservoirs affects the first definition, by removing specific
CO2 molecules, but not the second because exchange does not result in net CO2 drawdown.
And here he outlines the issue he sees with linear kinetics:
The most fundamental problem with the linear-kinetics formulation is that even the simplest
atmosphere/ocean carbon cycle models relax to a different atmosphericCO2 level, higher than the
concentration before the spike was released.
88.RB said
May 10, 2010 at 6:02 pm
Indeed, that is the official IPCC point of view: about 10% (or more) of the emissions stay in the atmosphere almost forever, based on the Bern model. But that is only true if we burn almost all oil and a lot of coal (3000-5000 GtC). If that happens, even the deep oceans CO2 content increases and as that comes back with some 1,000 years delay, it may increase the atmospheric content near permanently. At the past and current level of emissions (some 400 GtC accumulated, of which about halve absorbed by the oceans), we still are far from a huge influence on deep ocean CO2 content (some 38,000 GtC) and what is absorbed mainly stays in the deep…
My estimate was based on the work of Peter Dietze: http://www.john-daly.com/carbon.htm which is still valid, as recent investigations did show that the absorption of CO2 by nature still is going strong at a rather fixed ratio with the emissions.
Carrick, Tonyb
Just a question. Why not determine the amount of CO2 by the “old time” methods and see if the same kind of results the “old time”
scientists got are duplicated? Then the guessing game would be over and these discussions (maybe) ended. Probably no one could get a grant to do this.
Correct me if I’m wrong, but the tCA in your figure and the following text written by you appear to say the same thing.
The IPCC comes with much longer half life times, according to the Bern model. This is a combination of relative fast (upper oceans), slower (deep oceans) and very slow (rock weathering) sinks for the extra CO2. They assume that the first, relative fast, sink of CO2 will reduce in capacity over the years. Some media talk about hundreds to thousands of years that the extra CO2 will be in the atmosphere. That is true for the last part of the curve, as the smaller amounts of CO2 are getting slower and slower into the sinks. But the bulk (87.5 %) of the extra CO2 will disappear within 120 years.
Also, my understanding is that the Bern model with an a+ sum{c e^-t} equation form is for explanatory purposes while there is physical modeling of the carbon cycle processes used in model simulations.
Steve Hempbell:
There is plenty of replication of this, and the reliability of the measurement is plenty good enough….
The issue isn’t with the testing methodology per se, IMO, but with time of day when it is measured and the location where the sample is collected. You can get very large values of CO2 during periods of the day when there is very little mixing between the boundary layer and the atmosphere above it. Dawn and dusk are worst, if I understand it right, and night is worse than day. Ideally the measurements are taken midday, after the convective engine of the atmospheric boundary layer is fully cranked up. That ensures maximal mixing.
Even then, there are days with heavy cloud cover or rain where you still get poor results. Hence occasionally there are spikes at individual stations.
The most reliable way of doing it, is as it is done now. Carefully selected stations. with daily measurements performed in the early afternoon, and more importantly multiple sampling stations across the globe, so if any individual station shows a spike, it is almost certainly local contamination.
As far as I understand the history, prior to Keeling’s measurements in the early fifties that showed a strong diurnal effect (in this case, it was plant respiration that he was observing), it was not generally understood that a diurnal effect was present. It is actually a bit silly to expect people to have known about something that wasn’t known till a decade or more later.
I would personally say a graph like mine is much more likely to be accurate than Beck’s analysis of the historical CO2 level data. Among the other problems… contamination of a sample by e.g. regional scale urban activity or plant respiration can only increase the apparent CO2 concentration. Hence a pure average as Beck did is almost guaranteed to be biased high.
At the minimum, you pick the “low ball” values from Beck’s compendium of data, and if you do, generally it agrees with Antarctica data. Alternatively you only include data that have proper metadata associated with them and screen for those values that match modern accepted measurement conditions. You certainly don’t toss them all together like a salad and hope something delectable pops up!
Oh no! Another long atmospheric CO2 thread. Sorry, already been through too many of these to get more involved than to say Ferdinand is basically correct. The age of carbon will be over long before the deep ocean turns over even once. Yearly total ocean/biosphere absorption of CO2 will continue to rise roughly in proportion to the difference between actual atmospheric CO2 and pre-industrial CO2 (~280 PPM).
Nothing much to see here folks, move along, move along.
91.RB said
May 10, 2010 at 6:33 pm
Correct me if I’m wrong, but the tCA in your figure and the following text written by you appear to say the same thing.
Indeed, that is the same thing. The difference with the IPCC’s Bern model is that with a continuous absorption in the (deep) oceans and the biosphere, even after 120 years, the absorption goes further down, halving each further 40 years. The Bern model assumes that the (deep) oceans get saturated and that this will prevent the last 10-15% of the emissions to be absorbed by the deep oceans, so that much slower processes like rock/silicate weathering are needed. That may be true, but still is irrelevant for the past and current accumulated emissions. At maximum the deep oceans may respond with a 0.5% increase into the atmosphere, which will stay there for very long periods.
In graph form, the difference can be seen here:
http://www.vkblog.nl/bericht/262958/De_CO2-cyclus (last figure). The constant half life of about 40 years is based on the observed trends over the past 50 years of accurate measurements…
93.Carrick said
May 10, 2010 at 7:07 pm
The main peak around 1942 in Beck’s historical data is based on mainly two series, one of them is a long series taken at Giessen, Germany. Fortunately there is a modern station at Giessen, taking samples every half hour. That shows an enormous diurnal variation and in general a huge bias at the historical sampling times (3 samples a day).
Here the diurnal variation compared to several baseline stations:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/giessen_background.jpg where BRW = Barrow, MLO = Mauna Loa and SPO = South Pole.
And the monthly averages of Giessen, compared to Mauna Loa:
If you use only Beck’s historical data taken over the oceans or coastal with the wind direction from the seaside, then the ice core data are within the range of the historical data…
Re: Ferdinand Engelbeen (May 11 08:20),
A constant half life extrapolated into the past gives results that are much lower than the ice core data. A linearly increasing time constant gives a better fit to the MLO data for a strictly empirical relationship. The deep ocean storage capacity is vast, but the rate of transfer is also very low. The concentration in the shorter time constant sinks will increase and the decay would be to a higher level than before.
#96, Ferdinand, thanks for the comment and the figures.
The diurnal figure in particular was particularly fascinating, because it contains the exception that proves the rule. There are periods where plant activity actually produce a negative bias in CO2 concentration relative to global mean value. That’s pretty amazing.
Do you have a link to the raw data from the Gleissen station?
Carrick #98
I think your comment illustrates the reality of the graphic that heads this thread 🙂
A very well known climate scientist once admitted to me that we knew about 20% about what drives 20% of the climate, and nothing at all about the other 80%. ‘The known knowns and the known unknowns’ etc seems to me to have been a much more profound comment than it is given credit for.
Our continued lack of knowledge of a subject that has attracted so much funding and research is astounding, as is our assertion that we know enough to be able to form policies that will have profound impacts on our lifestyles and economy.
Personally I’m far more worried about energy securty, another Carringon event or a cyber attack (amongst other things) than I am about AGW.
It is a shame sceptics and warmists can’t concentrate on the things we can agree on, such as the need to look for alternative sources of energy, coupled with energy reduction.
Tonyb
“Damage from predicted warming is exaggerated”
Not exactly. It is FABRICATED! And it’s nonsense.
98.Carrick said
May 11, 2010 at 11:11 am
#96, Ferdinand, thanks for the comment and the figures.
The diurnal figure in particular was particularly fascinating, because it contains the exception that proves the rule. There are periods where plant activity actually produce a negative bias in CO2 concentration relative to global mean value. That’s pretty amazing.
Do you have a link to the raw data from the Gleissen station?
The diurnal variation only shows local concentrations, not CO2 flows, which may be highly negative: at night plants respirate CO2 and in general one has inversion, so that CO2 build up in the lower layers. During the day, photosynthesis is at work, but at the same time atmospheric mixing is increased, thus one doesn’t see the full withdrawal effect on local CO2 levels…
Giessen/Linden data can be obtained from the Hessisches Landesamt für Umwelt und Geologie (Hessian state agency for environment and geology):
http://www.hlug.de/
or directly from:
http://www.hlug.de/medien/luft/recherche/recherche.php?view=messwerte&detail=download&station=1005
where you can perform a download for CO2 and other items (best year by year, with multiple years, the download system may crash)
Nearby at the university of Giessen, an interesting CO2 enhancement experiment is at work at:
http://www.uni-giessen.de/cms/fbz/fb08/biologie/pflanzenoek/forschung/Foeinr/ukl-en/projects/giface
97.DeWitt Payne said
May 11, 2010 at 10:41 am
A constant half life extrapolated into the past gives results that are much lower than the ice core data. A linearly increasing time constant gives a better fit to the MLO data for a strictly empirical relationship. The deep ocean storage capacity is vast, but the rate of transfer is also very low. The concentration in the shorter time constant sinks will increase and the decay would be to a higher level than before.
If one takes the change in accumulation into account, the past smaller difference between actual and pre-industrial atmospheric levels can be backcalculated to near zero. That shows levels of about 305 ppmv at 25% accumulated emissions (around 1900), further back, that would be around 290 ppmv, not bad in this case (ice cores were 280-285 ppmv):
Don’t underestimate the deep ocean sink rate: that is about constant at around 60 GtC/year, directly or indirectly from the atmosphere into the deep, mostly at the THC sink place: the NE Atlantic. But near the same amount comes back at the Pacific equator. The balance nowadays is around 2.5 GtC/year sink capacity, depending of the pCO2 difference (which is several hundreds of microatm at the sink places). There is by far no saturation there, even not in the far future when the global CO2 levels should be back at pre-industrial levels. See e.g. the Feely e.a. pages:
http://www.pmel.noaa.gov/pubs/outstand/feel2331/exchange.shtml
86.Carrick said
May 10, 2010 at 2:59 pm
I’m certain it’s an important driver (forcing) as well as an important feedback.
If you read what I’ve said in the past though, there isn’t a linear relationship between CO2 and global mean temperature, the effect of climate on global mean temperature is more complex than just the turning of a thermostat up or down. And that is partly because it can either be a (parametric) forcing or a positive feedback (it amplifies the effect of natural climate forcings).
To this point in history, it has not played a dominant role in global warming. Partly this is because (it is thought) that anthropogenic sulfate emissions prior to circa 1980 nearly balanced the anthropogenic CO2 emissions (sulfates are a negative forcing of course), and partly because it isn’t really a huge effect anyway, compared to natural climate fluctuations. As James Hansen would say, increasing CO2 “loads the dice” of climate variability towards warmer temperatures. It behaves more like a increase in gain than a simple offset if you want an electrical circuit equivalent.
I beg to differ on these two points, here a repeat posted on the other (historical CO2) discussion:
What about the influence of CO2 as driver: the direct radiative influence of 2xCO2 is about 0.9 K, thus quite low. All models show a much larger sensitivity, based on mainly positive feedbacks. But that is very questionable: at the end of the previous interglacial (the Eemian), temperatures (and CH4 levels) dropped to a minimum and ice sheets increased to a maximum, while CO2 remained high. When CO2 levels dropped with about 40 ppmv, that had no measurable influence on temperature (or ice sheet formation):
http://www.ferdinand-engelbeen.be/klimaat/eemian.html
The same point for aerosols: their influence is likely overestimated in the models. Even the sign may be wrong (warming soot!).
There is an offset between aerosol (cooling) influence and GHG (warming) influence: the stronger the estimated cooling effect, the stronger the warming effect of GHGs should be to replicate the 1945-1975 cooler period. But that doesn’t explain the current halt in temperature increase…
See further: http://www.ferdinand-engelbeen.be/klimaat/aerosols.html
and the (very short) discussion on RealClimate:
http://www.realclimate.org/index.php/archives/2006/02/an-aerosol-tour-de-forcing/ with my comment at #6.
Ferdinand, of course I am aware of the distinction between radiative forcing of CO2, which accounts for 0.9-1.2°C/doubling, and the enhanced effect including positive feedbacks, that according to the models places it closer to 2.5°C/doubling.
Regarding aerosols, of course if you start by assuming no effect from CO2, then you are pretty much forced to do the same for aerosols. The soot aerosols don’t hold a candle to the sulfates, so to speak, you probably are already aware of why this is.
What we know is, from the models, prior to 1980 little to no anthropogenic forcing was necessary to explain the course of the temperature record since 1850, and that some anthropogenic forcing is needed since 1980.
Having said that, 10-years is too short a time period for a substantive test of the models. We already know the models don’t adequately capture short period climate fluctuations…you can see this just by comparing the typical scale length of these fluctuations and comparing it against the grid spacing of the models. So looking at 2000-2010 doesn’t tell you really anything new, expect perhaps the relative importance of natural fluctuations compared to anthropogenic ones.
30 year periods is sufficiently long to disambiguate most short-period climate fluctuations from secular forcings like CO2 and sulfates. I think this is also a long enough period of time for comparison with model outputs to be meaningful.
It is my opinion (and this is what the models themselves say) that perhaps 0.1°C of the warming prior to 1980 was due to man, and perhaps 0.2-0.3°C of the warming since then. While I’m on my soapbox, I also think that the data are already good enough to start eliminating really high sensitivities, like 7.5°C/doubling from a recent paper, and even Hansen’s favored value of 4°C/doubling is in grave danger of elimination.
You probably disagree with some of these views, so I think we’ll probably need to cordially agree to disagree. 😉
Re: Ferdinand Engelbeen (May 11 15:46),
I suspect you’re using fossil fuel and cement only carbon accumulation. That makes the 1940’s flat spot almost disappear. But if you start in 1850 with Law Dome data, you seriously overestimate the amount of carbon in the atmosphere. 10 ppmv doesn’t seem like much, but it’s 21,300 GtC in the atmosphere alone and about double that when sink accumulation is taken into account. Here’s a graph with and without land use CO2.
105.DeWitt Payne said
May 12, 2010 at 4:55 pm
Indeed, I only used the direct human emissions, as the historical estimates (even the current ones) for land use changes are quite uncertain. Earlier emissions from fuel use are uncertain too, but not at the same degree as land use changes…
It shouldn’t give much difference, as in the first case the increase rate is about 55% of the emissions and very stable since 1900, while including land use changes makes that 45% of the total emissions remained in the atmosphere. In both cases, the difference removed by nature. That means that land use changes were more or less in a fixed ratio to fossil fuel use (and both related to population growth). But more important: in both cases there is no indication of a reduction in sink rate over time.
I didn’t include the figures before 1900, as the yearly emissions were quite low and hardly outside the ice core (smoothed) accuracy…
Re: Ferdinand Engelbeen (May 13 10:44),
Land use change may be less certain than fossil fuel and cement, but not by all that much. It’s also of similar magnitude to fossil fuel and cement in the first half of the twentieth century (45 PgC land use, 50 PgC fossil/cement). Leaving it out makes the fit look much better and borders on cherry-picking. For uncertainty estimates, there’s this:
Re: Ferdinand Engelbeen (May 13 10:44),
We also have an estimate on total excess carbon emission to the atmosphere based on the change in the 13C/12C ratio in things like corals, which started to change in the middle of the 19th century. Land use change is estimated to be 3 times larger than fossil/cement from 1850 to 1900 (31 PgC, vs 11 PgC).
108.DeWitt Payne said
May 13, 2010 at 1:42 pm
I still have my doubts about the land use changes. Not only because of questions about the real clear cut of the forests, but also the balance of CO2 release/uptake between cleared forests and subsequent new uptake by agriculture, besides reforestration in other parts of the globe. Further, the general increase in uptake by the biosphere in general (based on the oxygen balance sinds about 1990), which is positive. That includes land use changes, as the authors only take fossil fuel burning (and cement manufacturing?) into account:
Click to access BenderGBC2005.pdf
But the pre-1900 period indeed might have seen a different ratio.
The coralline sponges indeed give a very clear answer about the flow of fossil fuel CO2 into the oceans. Here the picture which gives a nice view of the changes: http://www.ferdinand-engelbeen.be/klimaat/klim_img/sponges.gif
Re: Ferdinand Engelbeen (May 13 14:18),
There’s no question that the current uptake by the biosphere is currently larger than the contribution from biomass combustion. But you can’t explain the drop in 13C/12C during the 19th century with only fossil fuel combustion. It’s hard for me to believe that the estimates of gross biomass combustion were reasonable in the 19th century and early twentieth century but are wrong now. We know a big biomass sink cranked up around 1940, but I don’t think anyone knows exactly what it is. Sure, fossil combustion was fairly flat during that period, but again, biomass plus fossil and cement did a pretty good job of fitting the atmospheric CO2 data (and 13C/12C) until then and a much less good job after. I find it very hard to believe that the biomass estimates went suddenly very wrong, i.e. positive to negative, about that time.
What’s hilarious is that ALL academic signatories are denouncing the attack on climate scientists and the “pseudo conspiracy” skeptics love to refer to… because clearly the Allegre-Courtillot Masson Delmotte Petition and this US letter and the probable ones following must be uncorrelated spontaneous expressions… Just as cartoongate was back then in Denmark…