There’s a new post on Watts up With That (WUWT) by Dr Vincent Gray in which he extols the virtues of Roy Spencer and Murry Salby. I’ve already discussed the virtues of Roy Spencer in a previous post, so I won’t say more here.
What about Murry Salby though? Well, according to this post Murry Salby is a very clever bloke who
begins by showing the paleo record based on ice cores and shows that there is a close correlation between carbon dioxide and temperature, with temperature coming first. The same applies to methane.
He then attaches it to the more recent CO2 record and plots the Carbon13 figures, which declined over the whole period. Since plant material prefers C12 this means that the additional CO2 comes from plant material. The IPCC claims that the additional plant material must come from combustion of fossil fuels, so this is their “Smoking Gun” that the increase in CO2 is caused by human-derived emissions.
In paleo records, temperature does indeed lead CO2 rises, nothing there that challenges anthropogenic global warming (AGW) today. The main point is that the CO2 then amplifies the temperature rise and produces much larger temperature changes than could be explained by whatever was driving the initial rise (Milankovitch, for example). What about the second part of the statement above?
Well, the basic idea is that when plants grow, they preferentially use carbon-12, rather than carbon-13. Hence, the ratio of carbon-12 to carbon-13 is higher in plants than in the atmosphere. What Murry Salby is claiming is that since the carbon-13 fraction in the atmosphere has been dropping while CO2 concentration have been rising proves that it must be due to plants and is not due to our use of fossil fuels. In a sense he’s correct. It is due to plants. It’s due to plants that existed millions of years ago and have since turned into fossil fuels. It isn’t due to plants today.
What else does Murry Salby claim? Well he
then provides data and graphs which show that the additional CO2 results from what happens during a temperature fluctuation, using the satellite (MSU) temperature record since 1978. He shows that the CO2 which is released by a temperature increase is always greater than the CO2 absorbed when the temperature falls, providing a net increase in the atmosphere.
Indeed, he’s correct. As the surface temperature fluctuates, this drives fluctuations in the CO2. You can look it up and see for yourself. What Murry is claiming is that the amount that is added when the fluctuation rises exceeds the amount lost when the fluctuation drops and hence explains the rise. Indeed, in some sense, once again true. Why is this? Well it’s because, on top of these fluctuations, there’s an addition of CO2 to the atmosphere through our use of fossil fuels. What we have is fluctuations due to annual temperature variations plus a longer-term trend due to our use of fossil fuels. Just because one can associate temperatures variations with rises in CO2 doesn’t mean that all CO2 variations must be due to temperature variations.
This is the same logic as that used by Bob Tisdale who claims that because he can associate variations in the temperature record with ENSO cycles, that all the warming must be due to these cycles. Now Bob Tisdale has, as far as I’m aware, no actual scientific training, so maybe this is excusable. Murry Salby is, however, a Professor of Climate Science at Mcquarie Univerity so I find it more difficult to excuse his flaws in logic than I would those of Bob Tisdale.
Everytime I read this stuff I want to shake these people, just to hear whether there is any empty space in their head. Seriously, if we emit, on an annual basis, twice as much as accumulates in the atmosphere, *how can anyone claim we’re not the source of the increase* ?
As soon as they solve that conundrum, they can start thinking about why looking at fluctuations around the mean are not very good at looking at the trend in the mean. They get the tail wagging the dog…
A fundamental problem of Salby’s argument is that CO2 increases whether the temperature goes up or down (slide from Salby’s lecture). The CO2 inrease tends to be larger when the temperaure goes up than when it goes down, but the change in CO2 is always positive.
Your first point (we emitting twice as much CO2 as accumulates in the atmosphere) is the point, where I also don’t get what is going on into the brains of those people. It is simple math, you do not have to know one thing about the carbon cycle and how it works in detail.
You simply have:
CO2(n) = CO2(n-1) + 0,5 * y
where CO2(n) is the CO2 level of year n and y is our current CO2 emissions.
So clearly, if I we would stop emitting CO2 (and thus substract y from the above equation), we would get
CO2(n) = CO2(n-1) – 0,5 * y
=> CO2(n) < CO2(n-1)
So CO2 would fall. It is as simple as that. You don't have to know how the carbon cycle works in every detail: Simple math shows, that if we would stop emitting CO2, the CO2 concentration in the atmosphere would fall and not increase anymore. You don't even need to bother with CO2 isotope ratios or other things for that.
Seriously, people like Murry Salby are totally delusional.
I mean it is one thing, to argue without any supporting evidence that we are not the cause of the warming and that it is ocean cycles, cosmic radiation or what else might come into the deniers mind. But to argue that we are not the cause of the CO2 increase is not just stupid, that is stupid squared.
I don't known if anybody from you knows the Intelligence² debate series (http://intelligencesquaredus.org) .
They should also start a stupidity² or insanity² debate series. This would be an ideal platform where Murry Salby could debate Lord Christopher Monckton on who can make the most stupidest claims about climate science. Or Roy Spencer could debate with Michelle Bachmann about how it is possible for someone to believe the world is 6000 years old, but having at the same time ice core records where you can see individual annual layers of ice reaching back 800.000 years. Those debates could seriously blow up heads 😉
1) The most obvious problem with Salby’s carbon isotope argument is that C12 and C13 are not the only carbon isotopes. C12 is preferentially absorbed by plants, indicating the source of the increase CO2 is not from volcanoes, but from plant life, either modern or ancient in the form of fossil fuels. But the C14/C12 ratio in the atmosphere is also declining, indicating that the source of the excess CO2 is ancient carbon, ie, either volcanoes or fossil fuels. This was also mentioned by the IPCC, so Salby has no excuse for ignoring it (as if there could be an excuse for a scientist demonstrating complete ignorance of such basic facts in a field on which they are lecturing, and on material they have included in a text book).
2) Of course, the assumption that Salby acts out of ignorance is on very shaky ground. He has been caught in deliberate and blatant manipulation of graphs in a manner which can only be described as fraudulent. It should not be imagined that Salby believes what he says on climate science.
That seems to me to be the fundamental problem. Yes, there is a correlation between the annual temperature variations and annual variations in CO2 but there is clearly an underlying trend that is much longer-term than the annual cycle. To simply claim that this is because, magically, when temperatures rise it releases more CO2 than the amount removed when temperatures drop by the same amount seems absurd.
So, presumably the argument is that the dropping carbon-13 to carbon-12 ratio tells us it has to be related to releasing CO2 from plants. The dropping carbon-14 concentration in the atmosphere tells us it has to be ancient – hence fossil fuels. Seems fairly clear to me.
It is slightly concerning that there seems to be some evidence that these people are being deliberately fraudulent presentation. I can understand someone taking an extreme view from a science perspective. Maybe they realise that the evidence is weak, but there’s a chance, however small, and they just don’t want to follow the herd. To do so fraudulently, however, is very hard to excuse.
If C14 is mostly generated by cosmic ray acting on nitrogen, would not the solar maximum, that has till recently been in effect, reduce the incidence of C14.
If you look at the figure in the link in Tom Curtis’s comment, you’ll see that carbon-14 concentrations dropped from 1900 – 1950 (after which I think nuclear tests contaminated carbon-14 concentrations). That’s too long to be associated with the solar cycle (11 years) and solar irradiation actually increased during the first half of the 20th century. It doesn’t seem that one can explain the drop in carbon-14 concentration as being simply due to some change in cosmic ray flux.
Andrew, the abstract of Graven et al, 2012 reads:
The key thing to note is that while the C14 trend was strongly decreasing, the trend from production was slightly increasing over this period.
Further, it is not possible for moderation of production to drive a trend of -5.5%pa. C14 has a half life of 5,730 years, which equates to a fractional decrease of approximately 0.012% pa. Thus if all C14 production ceased, and no other effect was active, C14 would decrease by only 0.012% pa.
A good way to show skeptics/fence-sitters that Salby is “full of beans” is simply to “count beans”, accountant-style.
We know from economic data how many GT of CO2 we put into the atmosphere each year.
We can also, via simple middle/high-school math, calculate how much CO2 is required to raise the atmospheric CO2 concentration per PPM.
Simply calculate the approximate total weight of the atmosphere — the atmospheric pressure at the surface of the Earth multiplied by the surface area of the Earth will give you a good “ballpark” estimate that is close enough for our purposes (a few percent on the high side, but still darned close). Then calculate the approximate average molecular weight of the atmosphere (assuming 20% O2, 80% N2 will get you close enough) vs. the molecular weight of CO2.
Crunch those numbers a bit, middle-school/high-school style, and you will see that we’ve been dumping *far* more CO2 into the atmosphere than can be accounted for by the CO2 PPM increases.
It’s really amazing how these “skeptics” manage to fumble some of the most very basic “schoolboy” math/science concepts.
Indeed, it’s amazing that anyone is actually suggesting that it could be anything other than a consequence of our use of fossil fuels. What’s disturbing is that it is someone who is (or was – there is a suggestion that he may no longer be at Mcquarie anymore, but I haven’t had that confirmed) a Professor at a reputable university and hence his views are taken seriously by some.
Haven’t heard those rumours (his latest presentations, a few months ago, still have his affiliation at Macquarie), but I did notice that his publication record shows a clear and long-lasting isolation. He is mostly sole author on papers, has a few two-author papers, and even fewer three-author papers. Most of his co-authors seem to be junior scientists.
He has some highly cited papers and books, which to me suggests he’s done something useful, so one really wonders when, or for that matter why, he went off the cliff.
The rumour came from a comment on WUWT claiming that his university email address no longer works and the university has said he no longer works there. Not the most credible source, admittedly 🙂
Certainly, he does appear to have done some very good work. Trying to be a maverick? Maybe some overconfidence?
Murry Salby wrote an opinion piece in The Australian a couple of months ago, “Last summer was not actually angrier than other summers” http://www.theaustralian.com.au/national-affairs/opinion/last-summer-was-not-actually-angrier-than-other-summers/story-e6frgd0x-1226611988057.
What are your thoughts on academics who teach this stuff at the undergraduate level? I got into a debate recently with someone because Auckland University also has a climate change denier, Chris De Freitas, and a student of his wrote in the student magazine about how she objected to paying hundreds of dollars for a subject which presented graphs that Christopher Monckton had created http://craccum.ausa.auckland.ac.nz/?p=107. I think I would object to this as well. Someone said this was an attack on academic freedom and that academics should be free to teach whatever they like. I think they should be free to research whatever they like but teaching is different, as it is done on behalf of the department and the University as a whole and it is also, to a certain extent, driven by student demand. A first-year prerequisite subject in particular should present the science in its broadest range and not just a fringe idea. And it should present the science rather than Christopher Monckton’s ideas. I’ve gone off on a tangent here but I would be interested to know whether Murry Salby, if he’s still at Macquarie, teaches similar stuff to first year students.
Interesting question. I’m not sure that I have a particularly well thought out response. I think that you’re right that academic freedom applies primarily to your right to research whatever you like. So, in some sense, teaching is different and one shouldn’t be able to argue that academic freedom gives them the right to teach whatever they like. However, the issue that I can see is that if universities are hiring leaders in their field, who decides what is best to teach but them. If you start having strict rules about how to teach and what to teach, then who’s deciding and what’s the point of hiring research leaders.
Our department hasn’t quite had anything as extreme as including figures from Monckton in a course on climate change, but we have had examples of people who were teaching in a manner or at a level that really wasn’t suitable. We’d normally give them some leeway to see if they can bring it around or maybe realise that things are not going well (or maybe even see if they might be right about how they’re presenting the material), but in at least two cases they were removed and someone else took over teaching that course. So, certainly our department regards teaching as a departmental responsibility and although we don’t insist on teaching in a particular way, we do have certain restrictions and certainly reserve the right to insist on changes or to change the person teaching if things aren’t going well.
I think this is what the University of Auckland has done as Chris De Freitas is no longer teaching that subject. Perhaps the best solution in this case would be for full disclosure of what is being taught in the subject, and then allowing students to choose whether they want to study the topic or not.
Possibly. We normally have a brief syllabus and recommended textbooks but that probably still doesn’t stop someone from teaching something that most would regard as scientifically questionable. Admittedly, If someone like Chris de Freitas openly believes that his scientific views are correct, then he may be happy to make it clear that this is what he would be teaching and students could indeed make an informed choice.
Salby is not listed on department faculty page
and his publication list ends with a 2008 in press paper.
Interesting. The link I used was to a page that is part of the staff list for the department. If you follow the link to “about us” on the left of my link, he is still listed as a staff member of Environmental Sciences, but it does seem as though – from your link – he is no a longer listed as a member of staff of the Department of Geography and Environment. Admittedly, not that unusual to still have live links to faculty pages after someone has left.
I’ve just found the following. At the bottom of this link is a comment by a Professor Colin Prentice. This comment is stated as being a response to recent talks given by Murry Salby. Colin Prentice appears to be a Professor of Biology and what he has written explains both why recent global warming is anthropogenic and explains why Murry Salby’s interpretation of the data is incorrect.
We have on this thread, one Rachel, who describes herself as “Aussie. Wife. Mum.” calling Chris de Freitas a ‘climate denier’ and you just carry on without noticing.
Try dealing with what Salby has to say, regardless of whether he has a job, works at Macquarie etc. Maybe then we can begin to understand what he’s really saying. Salby is making very specific claims. It would be stupid of anyone to assume that Salby is simply unaware of the propaganda-level basic, orthodox understanding of how CO2 behaves. He’s attempting to accommodate known facts with better explanations. So, unless you point to a specific point he makes, and provide the objection, the above exercise (‘well, I think Prof Salby is saying ‘X’, ‘X’ is wrong because of blah blah blah) is useless. Keep your strawmen to yourselves please.
Are you commenting on my post or on Rachel’s comment? If on my post, why don’t you try reading it. I did indeed point to specific things he said and addressed them. I don’t think that qualifies as a strawman. You and I have had some interesting discussions in the past, but you’re not obliged to read what I write and hence are not entitled to tell me what to “keep to myself”. If you don’t like it, don’t read it. If you disagree, tell me why.
As far as what Rachel says. Okay, I have avoided using the term “denier” myself but have also avoided moderating anything said on this blog (by anyone). If you want to judge Rachel but what she says, go ahead (although I’d hope that you’d keep it pleasant). I’d rather, however, that you didn’t judge me by what others say.
You wonder why Shub is so concerned about someone using the term “denier” and then uses the term “propaganda-level” himself. Tone trolling much, Shub?
I think that publication page is just old. He does have papers after 2008, e.g. dx.doi.org/0.1029/2011JD016285 and dx.doi.org/10.1029/2011GL047266
E-mail address for correspondence is a bit odd, I must say, but stranger things have happened at universities.
But yes, he’s no longer mentioned on the faculty page.
Yes, I’d rather missed that little irony 🙂
Strange things do indeed happen, so it may indicate nothing of any particular significance.
High-school bean-counting math is all that is required to debunk Salby’s claims that natural sources are responsible for the additional CO2 in the atmosphere.
Perhaps you should try dealing with *that*.
Then do the math, mr bannog, Let us see it. Salby’s talk is quite long. I’m sure you can pick out where he says, what you say he says. And then show how it is wrong.
It’s actually in the Oxford dictionary under deny. It says:
“an anti-environmentalist campaign group that denies climate change”
But I am not a very good writer so if you can suggest a better word for me to use then I would be happy to adopt that.
I think he has above, but let’s run through my understanding of the basics. So the argument that Murry Salby is making is that plants preferentially use carbon-12 over carbon-13 and hence the ratio of carbon-12 to carbon-13 in plants is higher than the ratio in the atmosphere. Since CO2 levels started rising, the carbon-13 to carbon-12 ratio has been dropping. Murry Salby interprets this as indicating that it must be due to plants. The two possibilities are plants today, or plants that have turned into fossil fuels. How do we distinguish? Well, carbon-14 is created by cosmic rays and has a half life of about 5500 years. Therefore there should be no carbon-14 in fossil fuels while there should be some carbon-14 in plants to today. The rise in CO2 and the decrease in carbon-14 is consistent with being released by something that has virtually no carbon-14, hence fossilized plants and not plants today. That’s one argument.
The other is that we know how much CO2 we’ve released through burning fossil fuels. If the rise of atmospheric CO2 is entirely natural and not related to our burning of fossil fuels, then something must be sequestering all the CO2 we’ve released (it can’t be being turned back into fossils as that takes millions of years). As far as I’m aware, the only possibility is plants. So how can plants be absorbing all the CO2 associated with burning fossil fuels while at the same time doing something completely independent that has resulted (naturally) in a 40% increase in the atmospheric CO2 concentration. It can’t both be a source and a sink.
Do you really, honestly believe that natural sources are to blame for the ongoing CO2 increase?
The article by Colin Prentice which you have linked to is very good. He makes a good point about atmospheric oxygen, some of which gets consumed by the burning of fossil fuels so that the carbon can form carbon dioxide. Measurements of O2 have been declining as we would expect but that the rate is not as fast given the amount of fossil fuel burned. His conclusion is that the land must be taking up CO2 rather than releasing it, as Murry Salby suggests.
Interesting, I’d missed that. Is the point that for O2 levels to be declining slower than expected, some of the CO2 must be absorbed by plants who then released the O2 back into the atmosphere?
OK, shub, let’s do the math. Quick, back-of-the-envelope, bean-counting math. Rounded to nice, even, easy-to-crunch numbers.
1) Let’s assume, to a first approximation, that humans have dumped about 30GT (metric) CO2 per year into the atmosphere from 2002-2012 (2012 is the most recent year of full average annual data). This ballpark “”+/- 10-percent” figure is easy to verify from publicly-available records.
2) The 2002 avg CO2 concentration was: 373.22 PPM. The 2012 avg was: 393.82 PPM (linky: ftp://ftp.cmdl.noaa.gov/ccg/co2/trends/co2_annmean_mlo.txt)
3) OK, now for some math. We subtract the 2002 figure from the 2012 figure to get a change in CO2 concentration of: 393.82-373.22=20.6 PPM.
4) Now, for that 20.6 PPM — how do we translate that into GT CO2?
5) Well, first, we need to know that total weight of the atmosphere. We could look it up easily enough, but just for grins, let’s calculate an approximate “ballpark” estimate.
To do that, we need to know the diameter of the Earth and the average atmospheric pressure at the surface of the Earth. We’ll go with sea-level pressure for a quick and easy “ballpark” estimate. The estimate will be a few percent on the high side (because not all of the Earth’s surface is at sea-level), but it will be good enough for our purposes.
The Earth’s average diameter is about 7926 miles (sorry about the non-metric units — I figure that most hard-core “skeptics” are in the USA, and from what I know of them here, they don’t do metric units very well).
The formula for computing the surface area of a sphere is PI * diameter^2. Do that, and you get an approximate surface-area figure of 3.1416 * (7926)^2 = ~1.98e8 square miles.
A good figure for the average atmospheric pressure at the surface of the Earth is: 14.7 pounds/square-inch.
Now, let’s convert that to pounds per square mile to get the units to align with the units I used to compute the surface area of the Earth. Now, given that there are 5280 feet in a mile, and 12 inches in a foot, that would be 14.7*(12*5280)^2=59e9 pounds.
Multiplying that figure by the total surface area of the Earth in square miles gives
The approximate total weight we calculate for the Earth’s atmosphere in tons is:
1.17e19/2000= approximately 5.8e15 (5.8 quadrillion) tons.
That figure is a bit higher than the actual value (for reasons outlined above), but is still plenty good for our “ballpark” exercise.
6) Now, let’s convert that 20.6 PPM increase in CO2 concentration into tons of CO2 in the atmosphere.
We can start by multiplying the 20.6 PPM figure by the total weight of the atmosphere. That’s 20.6/1e6 * 5.8e15 = ~119e9 tons, which is not quite correct.
We have to account for the difference in the molecular weight of CO2 vs the average molecular weight of the atmosphere to arrive at the correct figure. The molecular weight of CO2 is:
12(molecular weight of C) + 2*16(molecular weight of O) = 44.
The approximate avg molecular weight of the atmosphere is, assuming that the atmosphere is approximately 20% O2 and 80% N2 (ignoring the trace-gases) is 0.2*2*16+0.8*2*14=28.8.
To correct for the molecular weight differences, we need to multiply the 119e9 figure by 44./28.8 = ~182e9 tons. That comes out to 181000 GT.
Now, let’s compare that 182000 GT of CO2 that was actually added (net) to the atmosphere over the past decade by the amount we dumped into the atmosphere over that same period of time, which is 10*30GT=300GT. Oops — that 30GT figure was metric tons. Got to convert it to ‘merkin tons by multiplying by about 1.1.
So — we dumped approximately 330 ‘merkin GT CO2 into the atmosphere over the past decade (actually, that number’s a bit low — I rounded down on the emission figures).
7) So how does the amount of CO2 we dumped into the atmosphere compare with the actual increase in the CO2 in the atmosphere over the past decade?
Well, that’s 330 GT – 182 GT = almost 150 GT CO2 that Salby has failed to account for over just the past decade.
Think about that, shub. We the actual increase in the amount of atmospheric CO2 is just a tad more than *half* of what we’ve actually dumped into the atmosphere. If, as Salby insists, the causes of the observed atmospheric PPM increases are natural, where did *our* hundreds of GT of CO2 emissions go? Were they magically sequestered by “carbon elves”?
Disclaimer: The above numbers were from rounded, “back of the envelope” calculations. Others’ figures may differ depending on their rounding conventions. But they won’t differ by very much.
Just spotted a typo (not significant):
“That comes out to 181000 GT.” should be “That comes out to 182000 GT”… There are probably others — oh, well…
Also, I think you actually mean 182e9tons = 182 GT not 182000 GT. Otherwise, seems about right 🙂
Arrgh! — how did that silly “thinko” get by me?
Guess it’s time for another cup of “go juice” (and maybe another “smart pill”)!
Wotts, I have a detailed explanation of the IPCC TAR presentation of the decline in O2 here. The O2 concentration has fallen less than would be expected from the combustion of fossil fuels both because of increased uptake of CO2 by plants, and because warming oceans outgas O2. Estimates of the exact sizes of these effects vary. Therefore, while the decline in O2 is confirmation of estimates of the magnitude of cumulative fossil fuel emissions, it does not help improve the accuracy of those estimates. Further, decomposition of organic matter is also a form of combustion. Therefore the uptake of O2 does not refute Salby’s specific hypothesis, although it does refute claims that the increase in CO2 is due to ocean outgassing or volcanism.
Addressing Rachel’s specific point, it is only possible to determine from the O2 record that plants have been taking up CO2 because we know the O2 decline expected from known consumption of fossil fuels. Absent that knowledge the data could equally be interpreted as a decline in O2 due to decomposition of plants. Therefore I don’t think the argument adds anything to the simple algebra that the known mass of CO2 increase in the atmosphere is less than the known mass of CO2 release by fossil fuel combustion.
Curiously, Salby acknowledges that the anthropogenic emissions are well known on his video, and affirms the formula that Increase in atmospheric CO2 = cumulative net emissions, from which it follows that net natural emissions are negative. FYI, dikran marsupial, aka, Gavin Cawley, has had his rebutal published, although directed at Essenghigh’s version of the nonsense rather than Salby’s.
Your calculations are good, but it does not address what Salby’s explaining.
Why does the CO2 evolve in the atmosphere out of phase with the temperature by a quarter cycle? – point around 11:00 min
What is the effect of underestimation of short time-scale variation of CO2 in the proxy record on the understanding of relationship between T and CO2? (around 26 min)?
Why is there a ‘systematic increase’ in CO2 since the 19th century?
“In reality, our knowledge of native sources of CO2 is limited”, at ~36 min. Is this true?
Are there native sources of C13?
This is the kind of discussion I am talking about. I am not interesting in accepting or rejecting the ‘rise of CO2’ etc etc. Those are not directly disputed by Salby. Salby does not dispute that coal and oil sources add CO2 to the atmosphere. Why waste time making it look as though he did?
You are entitled to your strong opinions about Chris de Freitas. I, too, have an opinion that de Freitas be allowed to do what he wants, as long as it is not illegal. Call him whatever names he wants, use any dictionary you want.
If natural sources were actually net contributors of CO2, then the atmospheric CO2 concentration would be rising *faster* than what could be accounted for with fossil fuel emissions. It’s that conservation of mass thing, you know.
Salby is running afoul of the law of conservation of mass. He’s hopelessly wrong for that obvious reason alone.
“Why is there a ‘systematic increase’ in CO2 since the 19th century?
Records of global fossil fuel use + the law of conservation of mass will answer that question.
Unless and until Salby can reconcile his claims with the law of conservation of mass, his position is a non-starter. There is no reason to waste any more time with his claims when his position runs afoul of the law of conservation of mass.
When we explain something, we need to explain everything. If and when, we try to collapse phenomena into our answers, it is possible our answer is wrong.
Why is the net emission rate of CO2 as shown by Salby’s diagram (appox 41 min)? Is he making a mistake? Is he being fraudulent? I would like to know.
“Net emissions evolves independent of the human contribution” – at around 41:30 min. This statement from Salby in no way contradicts, minimizes or overrules what’s been observed in comments above. He is remarking on properties that are observed. Whatever explanation/s we offer, must account for all observed changes.
I’ll have a go and I have tried to find these in Salby’s video, but haven’t found exactly what you’re referring to.
Well, my understanding is that temperature variations can drive variations in atmospheric CO2 concentrations which would exist even if we weren’t adding CO2. The reason is because the amount of CO2 in the oceans depends on temperature so when the Earth is slightly hotter, there is more CO2 in the atmosphere. Given that – in the absence of a source of CO2 – this variations should have no trend. The total amount of CO2 would be conserved. Quite why it is out of phase by a quarter cycle is unclear to me, but in this cycle the CO2 would be expected to lag temperature.
I’ve tried to find this twice unsuccessfully. Maybe I’m looking at the wrong video. Don’t really understand what you’re asking.
The general view, I believe, is that this is a consequence of our burning of fossil fuels. Not sure if there is any viable alternative. As caerbannog pointed out above, we’ve emitted twice as much CO2 as than amount the accounts for the rise since the mid-1900s, so it would seem harder to find some alternative than to simply accept that this is the source of the systematic increase.
I don’t know, but I suspect it depends on what one means by limited.
I don’t believe so. Carbon-12 and carbon-13 are both stable isotopes. Carbon-14 is created by the interaction of cosmic rays with nitrogen and decays back into nitrogen.
You haven’t answered any of the points I asked. They come from Salby’s talk. They are his points. Until you do that, you are answering only your representations of what he’s saying. They may be good for blog debate, i.e, creating an appearance as though a rebuttal has been offered. Not interested.
The global fossil fuel use contribution in the early part of the 19th century are much smaller compared to use in the pre-war industrial periods.
Shub, I was indeed looking at the wrong video. I didn’t realise there were two in the WUWT post. I’ll try answer your latter question about “net emissions evolve independent of the human condition”. As Salby’s own presentation shows, the human emissions are essentially a long-term rising trend that has no real structure. It’s clear, however, that CO2 concentrations do indeed vary with other factors (temperature for example). Since there is no real structure (short-term variations) to the long-term human induced trend, the only thing that one could correlate with the CO2 emissions on short timescale is variations that drive the short term variations. I don’t really see how what he has shown in any way disproves that there isn’t a long-term human induced trend or that the primary driver for CO2 rises is natural.
Look at 1 hr 4min graph. That is one of Salby’s conclusions. We need to show why that is wrong. Part of the answer, we know. CO2 kept increasing because humans are emitting. But, how is his explanation wrong, completely? Why does the integral of temperature match the CO2 curve closely?
Marsupial is a scientist who resides at Skepticalscience, ‘moerating’ passersby.
wotts, all the minutes I quoted are for the second video
Shub, Salby’s discussion of estimation of error in the ice core CO2 record is based on the false premise that firn air has the same CO2 concentration as atmospheric air. The firn is indeed open to the atmosphere, but at the base of the firn, ice bubbles are formed, trapping CO2. These do not form instantaneously, so that the ice bubbles at a given layer of the core will trap CO2 from a range of years, thus eliminating seasonal and ENSO signals in the ice core record. Crucially, Salby depends on that lack of an ENSO record in the icecores to estimate ice core uncertainty – assuming falsely that the initially trapped layers will show the ENSO record at least. That makes his estimate worthless.
There is an independent check, by the way, on the ice core record of CO2. Proxies that chemically trap C13 can be used to reconstruct atmospheric CO2 concentrations, and that has been done by Lisiecki 2010, showing great similarity between the records. If Salby’s critique had any merit, any signal from atmospheric CO2 would have vanished from the icecores prior to the holocene. Lisiecki shows that that has not happened. Indeed, Salby relies on that having not happened in his discussion of the correlation between CO2 and temperature. Apparently he does not even believe his own temperature estimates.
This leaves aside the most fundamental flaw in Salby’s position, ie, that emissions are a constant function of temperature. According to Salby physics, if you hold ocean temperatures constant above 1900 levels, that will generate constant emissions from the oceans. Based on physics, the rest of the world’s scientists believe that a constant temperature will result in the establishment of an equilibrium. We can use the ice core record (among other ways) to estimate the equilibrium increase in CO2 concentration for a given temperature increase. It turns out to be about 22 ppmv per degree centigrade. Salby, on the other hand wants to attribute a 100 ppmv increase to a 0.7 C increase in temperature.
I will start taking AGW deniers like you seriously when, and only when you exhibit the ability to recognize pure flat earthism such as Salby’s for what it is; and say so publicly on the sites on which it is posted and on which you currently regularly comment.
I have already linked to my discussion of Salby’s graph above, but here it is again. Seeing as how you direct us to a location in the video where he uses that fraudulent graph, I expect you to defend his tactic of changing relative scales between two comparisons between CO2 and temperature as good science, or repudiate Salby as a fraud.
You may also want to comment on the scientific merit of attributing CO2 increase to the integral of temperature based on a correlation coefficient of 0.63 (r^2= 0.4) rather than attributing it to cumulative human emissions (r^2=0.993). If we are going to base science on simple correlations without reference to physics or considerations of mass balance, why is Salby ignoring a near perfect correlation in favour of his preferred, but rather weak correlation?
Why does the CO2 evolve in the atmosphere out of phase with the temperature by a quarter cycle? – point around 11:00 min
If Salby is claiming that there are temperature-sensitive *natural* sources/sinks responsible evolution of CO2 in/out of the atmosphere, then the answer is painfully obvious.
The evolution of CO2 in/out of the atmosphere quite obviously depends on the temperature of those *sources/sinks*, not that of the atmosphere!
If one such source/sink is the ocean, then it is obvious that it is the temperature of the *ocean* that will drive CO2 outgassing/absorption. And the *ocean* temperature will *of course* lag the temperature of the atmosphere, for the same reason that the temperature of a pot of water will lag the temperature of the stove burner under it.
Given that terrestrial/ocean CO2 sinks/sources (soil/peat/water/whatever) have a *much* greater heat capacity than the atmosphere does, it should not be surprising at all that there would be such a lag.
It’s not like CO2 molecules in the ocean can remotely sense the temperature of the atmosphere and say to themselves, “The atmosphere has just warmed — it’s time to jump out of the ocean!”.
Does Salby wonder why his pot of water doesn’t boil immediately when he starts the stove burner under it?
Shub, I think Tom’s link is pretty much spot on. In Salby’s first graph (showing how the models track with CO2) he has a temperature change of 5oC on the left axis and a CO2 change of about 700 ppm on the right (140 ppm per degree celsius). In the figure where he shows that they diverge, he has 2.7oC on the left axis and 60 ppm on the right (22 ppm per degree celsius). He’s changed the relative scales. For a fair comparison of the observations in his second graph, his right-hand axis should have had a range of about 380 ppm (i.e, from 330 ppm to about 710 ppm) in which case the fit would have been perfectly fine. He’s made the fit look terribly simply by changing the relative scales of the two axes. I don’t think there is any other real explanation.
To clarify a bit more — as heat “sloshes” back and forth between the atmosphere and ocean (think El Nino / La Nina), of course the atmosphere/ocean temperature variations will be “out of phase”. It’s that conservation of energy thing. When an El Nino warms the atmosphere, the ocean will cool a bit due to energy loss (i.e. the energy it dumped into the atmosphere).
So it should not be surprising at all if temperature-driven ocean CO2 variations were out of phase with the atmospheric temperature, **because ocean temperature variations should not be assumed to be in phase with atmospheric temperature variations**.
And it is the *ocean* temperatures that drive CO2 outgassing/absorption.
If atmospheric and ocean/terrestrial CO2 source/sink temperatures *were* perfectly in phase (to keep CO2 variations *in phase* with atmospheric temps), then there’d be some energy-conservation issues to address.
Nice explanation. Thanks, Tom. Good rebuttal from Gavin Cawley too.
I sincerely did not mean to insult or offend anyone and I don’t think I have strong opinions about someone I have never met.
Perhaps I could say instead, a scientist who does not endorse anthropogenic global warming. It’s a little clunky and long but probably describes my writing style anyway 😉
Caerbannog, it is not true that the atmosphere warms the ocean. Changes in the atmosphere can make the release of heat gained from the sun from the ocean less efficient. That is also true of atmospheric temperature, increases of which increase back radiation, thereby reducing net cooling of the ocean. Nevertheless, the heat content of the ocean is so large relative to that of the atmosphere that where ever they are in close proximity, the temperature of the ocean governs that of the atmosphere.
Nor does heat “slosh” back and forth between atmosphere and ocean in any meaningful sense. Heat “sloshing” out of the ocean into the atmosphere in any measurable degree would raise atmospheric temperatures by absurdly large amounts. To some extent, heat does “slosh” between different locations withing the ocean, and that indirectly effects atmospheric temperatures to a significant degree, being the largest short term (<10 yrs) impact on temperatures other than very large volcanoes.
I am aware that the concept of heat "sloshing" between atmosphere and ocean has been used by at least one climate scientist, but I believe that was a figurative use – and it is a figure of speech that can only create confusion.
With respect to the lag of temperature and CO2 shown by Salby, I do not know exactly what he is doing there. Specifically, are his figures seasonally adjusted, and is he showing lag of CO2 concentration or emissions? It is not clearly explained, and without clarifying I have not confident response on that point. Nevertheless, it is well known that short term fluctuations in CO2 concentration are driven by changes in GMST. Because those changes are significant relative to the annual increase in CO2 concentration due to human emissions, that short term variation may well explain the lag. Specifically, human emissions vary little around the trend from year to year. Therefore they will not be a significant factor in lagged correlation. In essence, Salby's test of lagged correlation simply cannot test the relative virtues of a natural vs an anthropogenic cause of the secular trend in CO2 concentration.
I looked at your article. I remember reading it when it first came out.
There is a problem in your argument (in the skepticalscience article). What you call Salby’s ratio, is actually the models’. When watching the video, I didn’t think it was he making that claim either. I don’t see him making the claim that a 2ppm rise/year would lead to a 0.0069 C/year rise. That is your derivation. Salby’s using the graph to show how the models are creations dependent purely on CO2 to produce their long-term changes, because, among the models, the only residual output after averaging is a quantity that tracks CO2 evolution
Secondly, Salby is quite clear why he shows the graph (of model averages). That, is the timescale at which model output becomes useable.
The Scripps graph includes land-use change. Again, Salby is questioning the use of C13/12 ratios as well: the IPCC’s conclusion in the matter, “impossible”, because, of ‘the observed sensitivity of native emissions, both C12 and C13, to temperature.
Re, you last post. you’ve made Salby’s point yourself. The record of CO2 reflects quarter-cycle lagged changes in temperature, because, the temperature has a strong effect on its evolution.
Rachel, I apologize if my posts seemed terse and blunt as well. It’s just hard to get the tone if a ‘denier’ label is thrown in. I wish we had better shorthand.
The student you refer to, it appears, got inadvertently sucked into reading about one of the complex cases of Machiavellian science politics anyone could come across, from some of the worst possible sources of confusion, i.e., John Mashey and Deepclimate. This is the Soon and Baliunas episode where a bunch of climate scientists conspired, and almost succeeded in getting Chris de Freitas fired from his job, for the sin of herding an article by Baliunas and Soon critiquing the Mann hockey stick, to published form.
Shub ignores that Salby deliberately altered the scaling of the second graph to *claim* the two do not match. It is as close as fraud as you can get while still having some plausible deniability (“Oh, I did not notice that. Hmmm….”).
Shub, but surely Salby’s argument is that if you plot the models and the CO2 projections for the period 2000 to 2100, the model mean correlates with CO2 rises. He then claims that if you plot CO2 and temperatures for the period 1980 to 2012, they do not correlate – they deviate. However, if his second graph were to have the ppm range going from 330ppm to 710 ppm, then they would appear to match. His argument is based on a visual analysis of a graph in which he has changed the ratio of the two axes. Do you not agree with this?
Yes, but that’s on short timescales and is due to variations in the temperature of the ocean. I still don’t see how this can explain a long-term rise (i.e., if the concentration in oceans depends on temperature and mass is conserved, then without an additional source the rise should be cancelled by the fall) or why the existence of a long-term mean would produce anything different (i.e.,if the short-term variations are sufficiently large – as they are – the existence of a long-term trend will not reduce the quality of the correlation with short-term temperature variations).
Also, as others have pointed out, if the long-term rise in CO2 was being driven by the long-term temperature rise then the increase, since the mid 1800s, would be about 22 ppm, not > 100 ppm.
wotts, Shub would never agree to anything so damaging to denier reputations, regardless of the evidence for it.
Quite possibly, but if I ask the question directly and simply, then that it’s being avoided becomes even more obvious 🙂
Shub, you are perhaps technically correct that I should have defined Salby’s Ratio in terms of the ratio of the units on the Y-axis. In that case the ratio of degrees C/ppmv on the y-axis of the first graph is approx 0.007, while on the second graph it is approx 0.045. The ratio has been inflated by approx 640% between the two graphs. I calculated that ratio more accurately in the post, writing:
It is a simple truth that for any two straight lines with a positive slope, they can be made to arbitrarily diverge, or exactly coincide simply by varying the scale of the y-axis of one with respect to the other. Therefore divergence of lines in one graph does not show disagreement compared to lines that parallel each other on another graph unless the ratio of the scales on the y-axis are the same in both graphs. When the lines would be approximately parallel in both graphs if a common ratio of scales was used, but a different ratio is used, with the resulting, purely graphical difference being used to establish some point of interest, that is what we call “fraud”.
The quote below is transcribed in Tom’s link and recurs in Salby’s Hamburg talk. Salby says this when he shows the long-term future temperature and CO2 comparison from models. It it complete nonsense, as in individual model runs temperature is not increasing monotonically and the difference can be quite large between model runs, and even more so between different models. Here it is:
“In blue is the forecast evolution [change over time] of global temperature averaged over two dozen models of the IPCC. It increases monotonically [without reversal], achieving values three and a half degrees warmer by the end of the twenty-first century. The increase in global temperature should correspond to increasing CO2. In fact their correspondence is considerably greater. In green is the forecast evolution of CO2. It too increases, exceeding eight hundred ppmv by the end of the century. Global temperature doesn’t just increase with increasing CO2 – it tracks it almost perfectly. In the model world, changes of CO2 and global temperature are isomorphic, they have exactly the same form. Their relationship is so tight, you don’t even need a climate model. A fractional increase of CO2 entirely determines the fractional increase in global temperature.”
“Why does the integral of temperature match the CO2 curve closely? ”
The derivate of temperature matches the derivate of CO2 quite closely (with an offset and a slight delay).
By the way, what is the integral of the temperature?
(Sorry, it should say “derivative” in my previous comment).
Shub: “Why does the integral of temperature match the CO2 curve closely?”
Which integral of temperature?
If I integrate the HadCRUT4 temperature anomaly, the curve declines from 1850, flattens out in the 1960s and then starts rising again. The correlation coefficient is -0.65, with an r^2 of 0.42. If I integrate temperature in degrees Kelvin (or degrees Celsius) I get a straight line with a positive slope. The correlation coefficient is 0.93, with an r^2 of 0.86. (They differ in the third decimal place.) If I take the temperature from 1850, setting the baseline to the mean of the first five years of the record, the value falls until 1920, then rises more rapidly than does the normalized CO2 concentration. The correlation coefficient is 0.9, with an r^2 of 0.8. If instead I take the temperature from 1900, using the mean of 1900-1909 as the baseline, the curve start flat then rises – but it rises more sharply prior to 1940 than does the CO2 concentration, and less sharply afterwards. The correlation coefficient is an impressive 0.98, with an r^2 of 0.96.
I am sure that by fine tuning the arbitrary choice of baseline and starting point (and temperature series), it may even be possible to do better than that. All you establish thereby, however, is that you have left so much wiggle room as to allow you fit an arbitrarily large numbers of distinct curves by suitable choice of parameters. It is evidence of nothing except your willingness to manipulate mathematics to make a point independently of the evidence.
For comparison, the correlation coefficient of the cumulative industrial emissions of CO2 from 1850 is 0.99, with an r^2 of 0.98. The curve matches the normalized CO2 concentration closely after 1950, and only diverges slightly in the early twentieth century. Extending the curve further back in time and including emissions from land use changes improves the fit. The fit over the period of the Mauna Loa record is almost miraculous, with correlation coefficient of 0.9995 and an r^2 of 0.999.
To compare the normalized values of each of these integrations with the CO2 concentration as taken from the ice core record and Mauna Loa, follow this link.
As for Salby’s claim that CO2 tracks the integral of temperature, it is distinctly underdone. He owes as a clear statement of his choice of baseline and starting point; and a clear, non-question begging justification of those choices. Absent that, his claim shows all the intellectual integrity of his graphing techniques.
Shub, as far as this quarter-cycle lag is concerned, I have a few comments. It appears to be mainly for Murry Salby’s theory. If you look at the the actual comparison of the temperature variations and the CO2 variations, then there doesn’t seem to be a quarter cycle lag.
Murry Salby goes on to Fourier transform the data (or produces what he calls a coherence spectrum – not quite sure that I know what this is) and produce a a plot at about 14 minutes that shows some spectrum with a big spike at 0.025 mos-1. This big spike is clearly the longest period perturbation in the spectrum. If mos is s-8 then, as far as I can tell, this corresponds to a signal with a period of about 800 years. If so, this is clearly simply an artifact of the data that has a long-term trend. We don’t have a long enough temperature record to know if this is a sinusoid with a period of 800 years. He also plots the phase of the signal and shows that it is 90o but only for this very long period signal, which is – as far as I can tell – simply an artifact and not real. So, I don’t see any evidence in what he’s presented for an actual quarter cycle lag.
It is not Salby’s ratio. It is a ratio you derive from what he says.
Why is there any correlation at all between the integral of the temperature and CO2?
I think Shub’s latest response can reasonably be taken as confirmation of my estimate of his intellectual integrity. It appears that he cannot defend Salby, but cannot bring himself to say that Salby’s manipulation of the ratio of the scales of the y-axis is indefensible. So he disputes a point of nomencalture. Pathetic.
Short answer: There isn’t any such correlation! Until the temperature series, baseline and start point are specified and justified, I am entitled to take any choice of the three above in order to replicate the claim. Doing so by the simplest means available on the web fails to replicate the claim (but does show the trend in temperature to correspond to the trend in CO2).
Long answer, the record of CO2 concentrations is smooth enough that any straight line with a positive slope achieves a correlation of 0.9255 (1850 to 2008; r^2=0.8565). The rise in CO2 concentrations is approximately exponential, such that the correlation between the CO2 concentration and the curve given by 1.02^(year – 1849) between 1850 and 2008 is 0.9947 (r^2=0.9895). Further, the integral of a straight line is a quadratic curve. If, however, the line has a positive slope and initial value of zero, it approximates to an exponential curve. In fact, by choosing the initial value of the straight line, you can approximate closely to either the exponential curve, or, by ensuring the initial value is large relative to the increase in value over the line segment, arbitrarily closely to a straight line.
Therefore, by arbitrary choice of the initial value, you can ensure a correlation lying between that of a straight line and that of the exponential fit to the CO2 data. It is that simple. An integral correlating between those two values is, therefore, not evidence of a physical relationship, but only of a mathematical truth and an arbitrary choice of initial conditions. Only when he correlation of the integral of a value that approximates to a straight line is a better fit than the exponential fit to the CO2 curve is it of any evidentiary value, a condition not met by any integration of temperature I have seen examined.
Look! If I use abolute temperatures in Kelvin, the integral becomes an almost perfectly straight line going upwards!
Of course, it has been behaving like that since the dawn of times.
And I don’t understand why we have to discuss at all those things like C12/13/14 ratios and why we should give a rat’s ass about what the graph on 1 hr 4min in Salby’s video is showing. It does not matter at all.
We **KNOW** (just by accounting for the amount of oil, gas and coal that is burned every year) that humans are emitting **MORE** CO2 every year, than the actual increase in atmospheric CO2 is. So regardless of whatever Salby is claiming: Natural systems can’t be responsible for the current increase in CO2. Indeed natural systems like oceans or the biosphere takes even up nearly half of our emissions and **MUST** act as a carbon **SINK**. And we can observe and confirm this by independent lines of evidence, because the oceans are getting more acidic, e.g. are taking up CO2.
So Shubs points are just strawmans and red herrings, because we already *KNOW* that Salby’s claims are false. They are just simply disproven by observations. And all that crap about isotope ratios and correlations between this and that is just distracting from the big picture here, namely that Salby’s claims are already disproven by the observations mentioned above.
Wow, great *REASONING*, madness.
Shub, except he has a point. What’s the burden of proof? How do you define enough evidence? Basically, the amount we’ve emitted since the mid 1800s is something like twice as much as the measured increase in atmospheric CO2. So, the basic evidence is that for centuries (if not millenia) atmospheric CO2 concentrations remained reasonably constant. Suddenly in the mid-1800s it starts to increase and is now 40% greater than it was then and essentially 40% greater than it has been for at least 1000 years. So, what happened? Well, we also know that we started emitting CO2 through the use of fossil fuels. We also know that the amount we emitted is greater than the increased amount in the atmosphere. It would seem to me that the burden of proof should lie on those who are suggesting that despite us releasing enough to increase CO2 concentrations by 200 ppm, the observed 100 ppm increase is unrelated to human activity and while natural processes were a source of CO2 some other natural process suddenly became a sink so as to remove all the CO2 we’ve been emitting for the last 150 years.
So, the basic evidence is that for centuries (if not millenia) atmospheric CO2 concentrations remained reasonably constant.
How do we know this? Salby says we might have underestimated previous high values. And there is no “basic evidence” to make such categorical statements. I am not even disputing human CO2 contributions in the first place.
The present sinks are removing all CO2, except for a smaller fraction left behind each year. A warmer world is one which would have increased sink capacity (well except a cool ocean whose CO2 solubility characteristics dramatically increase with reducing temperature).
My point is just this: if Salby is questioning the assumptions based on which rests orthodox understanding, one can only refute him by answering to confirm the assumptions. I believe diagnosing overlapping changes of the same sign is not an easy task. Others seem to think they are a cakewalk.
Well we don’t know this in some absolute way, but we have evidence to suggest that this has been the case. I’m unaware of a real alternative (in fact, I’m not quite sure where Murry Salby has even suggested otherwise).
I also don’t think that someone who says “we might have underestimated previous high values” necessarily need refuting. This person should be engaging in the scientific process and presenting evidence that can be considered. If the evidence is convincing others will take notice. If the evidence is not, it might be completely ignored and the work that others are doing will continue regardless. I guess I’ve written a post about what he’s said and provided alternative explanations based on the evidence he’s presented, but I’m basing what I’m saying on the existing literature and am not claiming that what I write is evidence by itself.
I don’t really understand your point about the sinks. There’s clearly a carbon cycle in which CO2 moves through the atmosphere, the biosphere, the oceans, … An individual CO2 molecule has a reasonably short residence time (a few years I believe). However, we have to conserve mass and so all the CO2 we release has to be part of this cycle and the consequence appears to be (and the evidence suggests) that this is resulting in a continual increase in the concentration of CO2 in the atmosphere.
I would argue that that is precisely what is happening. The work on this has not suddenly stopped and everyone has suddenly decided that everything is settled. It continues and new measurements and techniques are being developed all the time. There’s also plenty of discussion about uncertainties and problems with measurements and techniques. However, the recent work continues to add to the evidence that the increase in CO2 in our atmosphere is anthropogenic and that global warming continues unabated.
SAlby’s point in the showing the linear relationship between CO2 and temperature in the models is to show that the same relationship doesn’t exist in the real world. His blue slide at the end part for that segment – he says this. It is the models (note the plural) which have this emergent property. By averaging their output, one can show their determinist component to be reducible to CO2. Is this under dispute? The near linear relationship between CO2 and the models well known
Your conclusion ?(with your bold): if Salby’s claims were accurate, an increase of 10 ppmv of CO2 would result in an increase of 0.069 C in Global Temperature.
Why did you scale only the CO2?
Black goat, why don’t you tell us what is the “integral of the temperature”?
Shub, he didn’t scale only the CO2. If you look at the first figure in which Murry Salby compares changes in CO2 and temperature between 2000 and 2100 then a 430 ppm increase in CO2 corresponds to a 3o C rise in temperature. Hence a 10 ppm increase in CO2 concentration corresponds to 0.069oC rise in temperature.
Shub, Tom’s article shows that that relationship *does* hold in real life. Salby had to change the scale on the y-axis for the CO2 to make the claim of a divergence between the models and the real world.
Salby’s claim is false. Either is was enormous incompetence in scaling his graphs, or it is deliberate and fraudulent misrepresentation. Take your pick of these two, there really is no third option.
This is my transcript of what Salby says during the second temp-CO2-graph:
“The long term evolution of global temperature parallels that of CO2 during the 1980s. It behaves less so during the 1990s, even accounting for the erruption of Pinatubo in 1992. But after the El Nino of 1997, CO2 continued to increase. Global temperature did not.”
It is obvious that his argument depends on the scaling. Choose a scaling which corresponds to a more realsitic relationship between temp and CO2, and his argument doesn’t make sense.
Are we talking about the same thing?
The linear relationship between the temperature and the models is a property the models exhibit.
This relationship does not exist for short timescales. Why is this difficult?
If you scale only the CO2 down, but not the temperature, then how are you reproducing the same scale relationship in Salby’s first graph?
“If you scale only the CO2 down, but not the temperature, then how are you reproducing the same scale relationship in Salby’s first graph?”
Because in the second graph (observed temp+CO2), Salby is not reproducing the same scale relationship as in his first graph (projected CO2+temp, mean of many models).
1) It is absurd to talk about just scaling CO2. Scaling can only be done relative to another term, so that what is adjusted inevitably is the ratio between the two terms. In this case, what is adjusted is the ratio between ppmv and degrees C on the y-axis. Very clearly that ratio differs between Salby’s graph of IPCC predictions (“model world”) and his graph of observations (“real world”). Changing that ratio inevitably changes the relative slope of the trend of the CO2 curve and the temperature curve. In this case, Salby adjusted the scale ratio in such a way as to increase the apparent slope of the CO2 trend relative to the temperature trend by a factor of 6.2.
Regardless of Salby’s intended argument, you should be able to recognize that change of scale ratio as intellectually shoddy, and to say so. Your grim determination to avoid doing so shows clearly that truth is your lowest priority in global warming discussions.
2) You appear to be trying to present an argument that Salby was merely trying to point out that observations showed large year to year variation in temperature, whereas the models do not. Salby actually claims the following (underlined text differs from his earlier video as transcribed in my post):
Now, if Salby is trying to make the point that you suggest, then it is not true that there is a close parellel between the evolution of CO2 and temperature in the 1980s as Salby claims. The 1980s exhibits a very large variation in temperatures from year to year, where no such variation is seen in the CO2 record. It follows that Salby is not making the argument you are suggesting. Rather, he is, and very clearly, trying to indicate that the trend of the observed temperature record and the observed CO2 record substantially diverge, after close agreement in the 1980s.
To make that case he has to tell a few fibs. He has to suggest that the CO2 tracks the 1980 trend in temperature on his graph, whereas it clearly has a much steeper slope than the actual temperature trends, whether of the 1980s or the whole series. He further has to suggest the y-axis ppmv/degree C scale was chosen to match IPCC models, whereas clearly it does not. And, of course, he has to use the big fib of the changed y-axis ratio. His entire argument is based solely on deception, and a transparent deception.
Shub, you finally found out what Salby did ‘wrong’: he scaled down one (in this case the temperature), but not the other when going from graph 1 (models vs CO2) to graph 2 (reality vs CO2). What Tom Curtis did was scale down BOTH.
Congratulations on finally realizing how Salby manipulated his audience.
It really is great reasoning. What exactly do you not understand with my arguments? We simply know, that we have emitted more CO2, than it has increased. For this to be mathematically possible, all other natural parts of the earth system must in aggregate be a carbon sink. Otherwise CO2 would have increased even more than we emitted, and that is simply not true.
All other things are just strawmen arguments, to distract from this main argument. So Salby’s claim, that the current CO2 increase is not man-made is just wrong. So even if all his other claims would be true (which they are not), this claim would still be wrong.
And to that:
“So, the basic evidence is that for centuries (if not millennia) atmospheric CO2 concentrations remained reasonably constant. How do we know this?”
Because we can measure CO2 e.g. from ice cores. And CO2 was not constant, it varied. But we *know* the CO2 levels from measurements since the 1950s, and we therefore know
“Salby says we might have underestimated previous high values.”
There is no evidence, that we underestimated previous high values. Salby’s just pulling such claims out of his ass.
First of all we have ice core data from all over the world, from Arctic and Antarctic Ice Sheets, over high-latitude glaciers up to mid- or even tropical glaciers. All those ice cores are in near-perfect agreement on the CO2 level for past time. All those glaciers have much different growth rates (from 20 meter snow accumulation per year to glaciers in cold deserts with only minor accumulation), at much different temperatures (from average temperatures of just below freezing up to -40°C freezing), at much different hill slopes and orientations (from steep north- or south-faced glaciers to basically flat glaciers) and with much different summertime melt (from extensive melt every year up to nearly no melt at all).
If one would assume, that those air would be not trapped as expected, you would certainly get all kinds of different CO2 values, depending on what glacier type you would look. But that is not what we find. So to assume that CO2 ice core data are wrong, just because Murry Salby, who has no expertise in ice cores at all, says so, is just completely nonsense.
Besides that, there are also other methods by which past CO2 can be derived (like from phytoplankton isotope ratios or leaf stomata). And while they don’t have such a good resolution like ice cores, you can at least compare them with ice core data and see if they paint the same picture. And they do. So to suggest, that all basic climate science is flawed, you have to do better than just claim so. And for the increase from 320ppm to now 400 ppm we have direct measurements and know that humans caused that increase.
Yes, I should have left the millenia out when I referred to it being roughly constant. I was thinking of the last thousand years, rather than thousands of years 🙂
“Salby says we might have underestimated previous high values.”
Salby is very unclear in his exposition. If, however, you look at the graph at 0:25:54 of the video, you see the effect of damping from all sources on the ice record according to Salby. Crucially, as the period of fluctuations gets very large, the ratio of atmospheric CO2 to ice core CO2 approaches one, ie, the error in the ice record approaches zero. By Salby’s account, even fluctuations with a period of 100 years (0.1 Kyr) are largely conservative. It is only for fluctuations of less than around 20 years duration or less that atmospheric CO2 might vary by a factor of 15 relative to ice core CO2.
In other words, Salby is simply pointing out that there could be very large, very short term fluctuations in atmospheric CO2, and the ice core record would not show it. Instead, the ice core record would only show the 100 year average over that period. We know, however, from direct observation that the atmospheric CO2 does not vary by a factor of 15, or even by a factor of 1.1 over twenty year time scales. Therefore Salby’s calculation of potential short term variation within the ice core record is of theoretical interest only.
Even so, Salby underestimates the resolution of the ice core record. He bundles damping from all sources – feedbacks on atmospheric CO2 concentrations (such the CO2 fertilization effect), damping in the firn, and damping in ice – into one factor. In fact these are all very different, and so bundling them leads to inaccurate conclusions. First, feedbacks on atmospheric CO2 directly effect the concentration in the atmosphere. They help limit the size of the short term fluctuations in CO2 concentration – a fact we all know from their limitation of increase in CO2 concentration to about half of human emissions. But Salby was trying to analyze the inaccuracy of the ice core record of atmospheric CO2. Including limitations on the variation in atmospheric CO2 in that analysis is therefore illegitimate.
Second, the firn damps variations in CO2 at a very significant rate. The upper firn is permeable to the atmosphere. Therefore the upper layer reflects the current atmospheric layer. As you go deeper into the layer, however, the firn becomes more and more compressed, sealing of ice bubbles containing pockets of air. The firn does not seal at a given layer instantaneously. Consequently each layer of ice will contain ice bubbles sealed at various times between the first deposition of the snow, and the final compression of the firn into ice. Each layer of ice, therefore, represents a lagged multi-year average of CO2 concentration. The damping is very strong, but time limited. It cannot continue over more than the period it takes for the firn to form into ice.
By including firn damping, and ice damping into one term, Salby exaggerates the later, and removes the time limit on the former. It is true that for ice cores, even with annual resolution of layers, each layer represents (approximately) a thirty year average of CO2 concentrations; but there is no evidence of significant loss of resolution once the firn is turned to ice beyond that implicit in the loss of resolution as different layers are compressed together.
If Salby were serious in his analysis, he would analyze firn damping separately to ice damping using the actual atmospheric record as his benchmark. He would then compare the power spectrum of CO2 concentration in ice with depth to the power spectrum of resolution. Only if the former exhibited more damping than the later would he have evidence of continued damping in ice.
And, seeing I had prepared it before, here is a link to Fig 2 of Lisiecki 2010, the bottom panel of which compares atmospheric CO2 as determined from benthic dC13 with that determined from ice cores. It clearly illustrates that the ice core record captures the past evolution of atmospheric CO2 at the level of resolution of the ice core records.
Salby appears to have been canned…
Some news about Salby and in particular his misuse of NSF grants.
“The Subject’s fifteen-year-long pattern of deceptive statements to his University and to NSF disguised his participation in entities and activities that existed for the purpose of maximizing his personal financial compensation and shielding the extent of his compensation from discovery or accountability.”
“The most egregious act of misconduct is the deficient and likely fraudulent** preparation of the Subject’s time and effort reports for Company 2. However, the Subject’s actions over a period of years displays a pattern of deception, a lack of integrity, and a persistent and intentional disregard of NSF and University rules and policies.”
Interesting background on Salby from John Mashey at DeSmog.
Salby, it turns out, has form. Lots of it. Let’s hope this important but until now missing context becomes as well-aired as Salby’s misleading claims about CO2.
Lars Karlsson – we crossed – sorry…
Wow, that’s quite remarkable. Let’s just wait and see how long it takes for this to be highlighted on WUWT.
That is a very damning report indeed. It seems odd that he refused to honour his teaching commitments. Jo Nova (well-known Aussie…I really don’t want to call her a skeptic because I don’t believe she is by definition skeptical but denier is apparently insulting…) is reporting that he was relegated to the role of teaching assistant – http://joannenova.com.au/2013/07/macquarie-uni-responds-to-murry-salby-what-they-dont-say-speaks-volumes/
First, “denier” is not insulting. The term has been in use as longer than modern english (ie, the time of Shakespeare), being used to mean “somebody who denies something”. Most frequently, until the twentieth century it was used to describe “Peter the denier”, so called because according to the Gospel’s he denied “Christ” three times. Deniers take insult at the term because it is rhetorically convenient to do so (or because they have been indoctrinated). Not using the term merely allows deniers to define the language of the debate. It is certain that any substitute term used in its place will also be found “insulting” unless it is transparently complementary, eg, “rational inquirer”. (And Joanne Codling, aka, Jo Nova is definitely a denier, having less intellectual honesty than Anthony Watts IMO.)
Second, the entire thrust of her argument is that research is more important than teaching. Even if this is so, however, it is standard practice for university professors to teach. It’s even what the title means – ie, somebody who professes their knowledge to students. Formally, the research role in universities is strictly secondary and while universities like (indeed, insist) on active research, they also insist on taking up some of the teaching load so that other professors are not left carrying the bag (thereby restricting their research time).
Oh yes. Let us pause in remembrance of “sceptic”. A word traduced. The hijacking of language by contrarians should be firmly resisted. Denial should – must – always be called by its proper name to prevent the intended creeping and false legitimacy.
The contrarian assault on language parallels its assault on science. Shock, horror.
I agree, teaching is very important which is why it’s so odd that he’d just not turn up to lectures. It’s almost as though he wanted to be sacked.
You are assuming in your calculations that natural carbon emission/sequestration is constant year-to-year or negative. Yet, according to ice cores and proxy records that clearly has not been the case. Your naive logic is just as maddening as anybody else. You, Salby, I, scientists, all agree, the ONLY thing we can accurately measure is human emissions based upon fossil burn and the amount of concrete we pour each year. The rest is conjecture, model, and innuendo. Do you find it the last bit bizarre that we are emitting carbon at a record rates, Mauna Loa hit 400ppm, and yet our projected temperature is not as bad as predicted? Do you ever ask, what the hell is going on? If you have 100% confidence in the models’ predictive capability, I would call you a very poor scientist indeed. Or simply somebody who got on the bandwagon without really questioning where it was headed.
Asking reasonable questions is called being a “Luke warmer” — excessive C02 emissions can’t be good, but the dire predictions of climate models isn’t panning out. That implies that proposed (expensive) solutions probably won’t accomplish much (except to move money around). Why the implication? Because we really do not understand the climate system. Why it naturally fluctuates? how it recovers from ice ages or cools from high temperature. All the IPCC models show accelerating without bound warming. Yet, good ‘ol mother earth has gone through temperature (and hence CO2 chanegs) whether or not the changes are caused by CO2 or CO2 is by-product of temperature change or if reality is a mixture of the two. Earth has a climate regulation system, that the models simply do not capture. None of the above “denies” rising temperature, excess CO2 emissions. It doesn’t take sides on whether Salby is misguided or is Galileo. It simply observes that models ain’t right.
Unreasonable first ignores the fact that we have accurate measurements of the isotope levels of Carbon (C12, C13, and C14) which remove the need for any conjecture as to whether or not the atmospheric CO2 increase is anthropogenic in origin. Indeed, he ignores all but one of ten lines of evidence that conjointly establish the anthropogenic nature of the increase in CO2 concentration. In that way he establishes his credentials as a “luke warmer”.
He then goes on to ignore that even for those models that do reproduce ENSO fluctuations in the tropical Pacific, they are unable to predict the exact timing of those fluctuations. Therefore the multi-run mean will not contain an ENSO component. In a simple experiment, I added to a 0.2 C per decade linear trend, starting in 1996, an El Nino fluctuation of the size of the 97/98 El Nino in 1997, and a La Nina fluctuation equivalent in size an magnitude to the 2008 La Nina in 2008. The resulting apparent linear trend was less than that actually observed. In principle, at least, it follows that the recent ENSO history may be sufficient cause for the difference between multi-model mean predictions and observed apparent trends over the last 16-17 years.
Indeed, we suffer an embarassment of riches, for on top of the negative ENSO trend we have a reduction in solar forcing (not predictable by climate models) and a faster then predicted increase in aerosols, both of which also suggest that if the models have indeed got the physics right, the short term multi-model mean prediction will be too high, but which have little significant bearing on the long term prediction.
The science is not settled on this point, and possible solutions of the discrepancy run from short term cooling factors being less than current observations suggest, to the underlying trend being greater than that predicted by the models. Again, being a “luke warmer” requires ignoring any evidence that would suggest the models are not overly pessimistic. Even when it is as in your face as ENSO.
Tom Curtis, it is a very interesting observation that the rise in CO2 concentrations is approximately exponential, with a base of 1.02. If you integrate over an exponential function, you get an exponential function with the same base. So you can get a perfect fit between the nonintegrated and the integrated functions.
As temperature (T) roughly follows CO2, this means that the integral of T would also resemble an exponential function, with the same base (1.02). That would explain the good fit between T integrated and CO2.
Rachel: A definition of ‘skeptical’:
It is an apt word, it does not differentiate fact or truth from belief. ie, You can be skeptical of something and actually be wrong about it. Or two people can each be skeptical of the other’s viewpoint.
skeptical skep·ti·cal [skep-ti-kuhl] adjective
1. inclined to skepticism; having doubt: a skeptical young woman.
2. showing doubt: a skeptical smile.
3. denying or questioning the tenets of a religion: a skeptical approach to the nature of miracles.
4. ( initial capital letter ) of or pertaining to Skeptics or Skepticism.
Gentlemen and Ladies if I may say, after a long and interesting thread. “The Parrot is Dead”
So, you folks would invite Salby to post here and debate with you over his finding then? Or are you planning on publishing something in a real journal to counter his assertions? I mean, you can’t dismiss him – he wrote the textbook many of you may have used in your intro atmospheric science classes and has no record of questionable science. In fact, he has more authority than anyone on this site as far as I can tell.
If you all are so sure, do the rest of us a favor and show him up – face to face. Do it for the planet, do it for the people. I dare you…
Hold on a minute. If Murry Salby had actually published a paper with his scientific ideas about global warming, maybe you’d have a point, but he hasn’t. Just because he wrote a very good atmospheric physics textbook that many have used, does not mean his most recent, unpublished ideas have any particular merit.
Glenn, did you read this thread at all? I recommend Tom Curtis’ responses, who shows several of Salby’s unpublished assertions to be incorrect. The worst, however, is Salby’s “creative” graphing (http://www.skepticalscience.com/salbyratio.html), which in my book comes down to scientific misconduct. If I were an Editor and I would be so unlucky to have those two graphs published, I would have likely retracted the paper with or without the author’s consent (I’d give the author a chance to correct the record – but in Salby’s case it would shut down one of his main arguments and thus relegate the paper into “nothing new, nothing new at all”). Oh, and I’d remove the reviewers from my database for not noticing this “creative” graphing.
One may wonder what happened to Salby who indeed wrote a useful textbook, but has since his debacle in Colorado gone down the path to obscurity. Which may explain something…
Glenn Donovan, Salby has indeed published a recent text book (2012), but it is unlikely that anybody here has used it because, first, it is very recent, and second (and more crucially), he has used it to present some of his theories which flatly contradict the consensus on the subject. That later amounts to academic misconduct (IMO), not because he presents the theory, but because he does not signal that they are in disagreement with the scientific literature on the subject; and because he did not first publish his theories in the scientific literature before including them in the textbook. It appears to be his attitude that he doubts he convince the experts, but is determined to try and convince the non-experts. That is, his chosen method of “science” is indoctrination.
As to his authority on this subject, he has not published a single scientific paper on the subject. Nor does he give any evidence of having read the large literature on the subject. On that basis he would be less expert than I am in that I have at least read some of the more significant literature. (Note, I am not claiming to be expert. I am only claiming Salby is not expert on the origin of excess CO2 in the atmosphere because he fails a minimum criterion of expertise, ie, knowledge of the reasons acknowledged experts have for their views on the subject.)
There is simply no excuse for Salby’s “creative” graphing. It is downright disgraceful.
The correlation between CO2 and temperature ended 16 years ago (this, despite the fact that one third of all the human CO2 emissions ever emitted have occurred during this time frame). How much longer must this divergence exist for you guys to move on to the next environmental scare?
It didn’t actually. If you’re referring, in particular, to the figure that Murry Salby uses to claim this then his comparison is completely wrong and easily shown to be wrong. If you’re genuinely interested in knowing why, try reading the link in the comment Marco makes above. If you’re still not sure why it’s wrong, I’m happy to explain further if you wish. Maybe you could actually convince me that your “for you guys” turn of phrase was just a slip rather than a gross generalization.
Also check this out: Recent global-warming hiatus tied to equatorial Pacific surface cooling.
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Something I would be interested in is anyone’s comment about the Ice Core record, and the relationship between CO2 and temperature over time. These records – some of which go back over 900,000 years – show that as temperature goes up, then the CO2 levels go up afterwards with a delay of some hundreds of years. Even more interesting was that after the CO2 increases, there was no ‘knock-on’ effect on temperature. No evidence of any positive feedback there, in fact the lack of an effect after the CO2 increase may more likely indicate a negative one.
The highest probable projections for temperature as given from the Climate Models show that the measured and ‘projected/predicted’ have diverged to an unacceptable degree, with no actual warming for ~ 17 years. Isn’t it about time to say that CO2 is not important to the climate and admit this so-called science obsessing about CO2 is wrong.
Another question is why have you created a look-a-like copy pseudo-website of http://www.wattsupwiththat.com rather than going to an existing one like Climate Audit and agree to have an honest and ‘scientific’ debate with the likes of Salby etc. Rather than playing propaganda games behind their backs.
Well, it has to lag because these cycles are driven by variations in the Earth’s orbit around the Sun that change solar insolation (both in terms of total incoming flux and where it is being deposited).
This is incorrect. The only way to explain the temperature variations is that CO2 is providing a positive feedback. In fact, these cycles are entirely consistent with an ECS of 3oC per doubling of CO2.
Because I felt like creating my own site. Maybe copying WUWT wasn’t the best decision I’ve made in my life, but it’s a bit late to change that now. What about actually going on CA or WUWT and having an honest debate? If I thought that was actually possible, I’d do so. Given that it almost certainly isn’t, I write my own blog instead. It’s a free world.
What Wotts said, but if you are interested in the detail, there is an important paper by Shakun et al. (2012) that examines the detailed mechanisms behind the last deglaciation. CO2 is indeed a feedback to orbital (Milankovitch) forcing, but it’s simplistic to say that “CO2 lags warming”. More correct to say that CO2 lags initial warming then contributes to full, globalised, deglacial warming.
In summary, this is Shakun et al.’s detailed chronology:
– NH summer insolation increases from ~21.5ka especially at high latitudes (orbital forcing)
– By ~19ka, mid/high latitude NH temperature increase causes sufficient melt from NH ice sheets for freshwater flux to inhibit the sinking of cold water in the high latitude N Atlantic, and the Atlantic Meridional Overturning circulation (Fig. 2) shuts down
– NH now *cools* as equatorial >>> poleward heat transport stops
– With the NH ‘heat sink’ turned off, the SH *warms*, as it must
– Deep water warming in SH ocean causes release of carbon to the atmosphere. This positive feedback globalises and amplifies the warming
– NH melt resumes, fully engaging strongly positive ice albedo feedback
– Deglaciation accelerates until largely complete by ~11.5ka. Holocene interglacial begins
I think if you disagree with someone you talk and debate, especially if it is science – that is one place it should be possible, and in the end the facts will decide e.g. on global temperatures. You may find that Steve McIntyre etc will give a fair hearing on their sites if you honestly try to approach them.
Some of the things I’ve read on the links posted on your website about Salby are little better than vicious character assassination, especially as this corrosive propaganda is put out behind someones back and although I don’t consider myself religious I would say that ‘he who is without sin cast the first stone’. It is possible to pull out facts about any of us and post them in the most unfavorable way possible, these tactics are plain wrong. I would expect these from the worst attack dog of the Republican right in the USA in a dirty election campaign.
On the matter of various cycles affecting insolation etc this has nothing to do with the reason why CO2 increases hundreds of years ‘after’ the temperature increases. If the CO2 rises after the temperature increases as shown in the ice core, then the feedback is not shown to be positive in the way you describe. Temperature should not be falling afterwards (for example), and we should see a pretty immediate temperature ‘bump’ upwards after the CO2 increases if the positive feedback is there at all. After all it is ‘claimed’ in the computer models that there is supposed to be a pretty direct and immediate link between CO2 increase and temperature – supposedly over the last 150 years for example – and with CO2 leading. Can anyone see the immediate secondary ‘bump’ up in temperature after CO2 increases in the ice cores ?
Would you do me the courtesy of reading my response to you above before repeating your incorrect claims?
Mike, you cannot come here full of righteous dudgeon about comments regarding Murry Salby and at the same time recommend Climate Etc and Climate Audit as appropriate places to discuss climate. When Judith Curry and Steve McIntyre withdraw their various accusations of fraud – when they admit that the various victims of “climate gate” were rightly exonerated by the appropriate inquiries, and the entire fiasco was based on stitching people up based on out of context quotation, perhaps then you can rant about “attack dogs” and tactics which are “just plain wrong”. When they stop standing shoulder to shoulder with Anthony Watts who gives the conspiracy theorist Christopher Monckton a platform to extend his vicious attacks on scientists, who he describes as parts of a conspiracy to create a “global, bureaucratic-centralist dictatorship” by “the new Fascists”; and his threats “come for” the scientists and “lock you up”; perhaps then you can site their blogs as places for reasonable discussion.
But in the meantime, such rants will be met by gales of laughter!
Learn a little self awareness!
Oh sorry. I thought I did. Can you explain exactly what you mean by :-
“Well, it has to lag because these cycles are driven by variations in the Earth’s orbit around the Sun that change solar insolation (both in terms of total incoming flux and where it is being deposited). ”
Is there a reference for this ?
Oh and a poster mentioned Shakun et al on the which comes first CO2 or a temperature increase, I think the CO2 lag still stands :-
I’m somewhat out of contact for a few hours so will respond in more detail later. A search for Milankovitch cycles will tell you much though.
I asked you to read my comment – including the link – not dodge it and link to disinformation from a political lobby group. Can I remind you of your own words, just above:
Walk the walk, please. Or as Tom cautions, laughter will follow.
Tony Curtis : in response
This is the kind of reactive, intolerant, and opinionated nonsense that has politicized and made impossible any debate over the science.
Your criticism of Steve McIntyre is not accurate. He has exposed and continues to expose shoddy and biased scientific output. He has forced retractions of scientific papers even after publication e.g Gergis et al. 2012
Roe, G. (2006), In defense of Milankovitch, Geophys. Res. Lett., 33, L24703, doi:10.1029/2006GL027817.
Click to access MilanDefense_GRL.pdf
Or if you are feeling ambitious:
Now, Mike, are you going to respond substantively or simply blither on?
Are you the Mike I used to talk to at Bishop Hill btw?
Mike, a paper can only be retracted after publication. Also, my given name is not Anthony.
In the mean time, I am enjoying the shouts of “black, black, black” from Mike Kettle after his initial two rants. Intolerant? Opinionated? ROFLMAO
As it happens, McIntyre takes on a very large number of targets from a very restricted choice of possibilities. If you write criticizing the IPCC concensus, you are immune from his criticisms. If you make a reconstruction that shows MWP, likewise. But if you are one of “the Team” (little bit of objectification and vilification of opponents there, straight from McIntyre’s poisonous pen) you will be hammered on the smallest detail – even if McIntyre has to be wrong (sometimes absurdly wrong) to do so. That shows that what he is doing is politics – as does his bedfellows. Given how prolific are his attacks, yes he occasionally gets something right. But more often he beats trivialities up into capital offenses; and sometimes is just outright wrong in a major way.
CO2 both leads and lags temperature. For a clear explanation of this I recommend The “800-year lag” unravelled. The scientific journalist, Peter Hadfield, explains it very well. He says, “Just because an increase in temperature puts more CO2 into the atmosphere, which is true, that doesn’t preclude CO2 also causing temperatures to rise.”
It goes like this (credit to Peter Hadfield’s video):
Orbital forcing -> temperature rise causes oceans to warm, stronger winds, melting ice -> positive feedback — more CO2, more methane and lower albedo -> more CO2, more methane and lower albedo causes temperatures to rise further -> temperatures rise causing oceans to warm and ice to melt and so on. The greenhouse effect takes over from orbital forcing.
The 800-year lag that is discussed in the move “The Great Global Warming Swindle” refers to data from the Vostok ice core which does not record global temperatures. It records Antarctic temperatures. Temperature does lead CO2 in Antarctica but temperature lags CO2 in the Northern Hemisphere.
Rachel’s link is very helpful. Consider it alongside Shakun et al. and hopefully the confusion over the role of CO2 in deglacial climate change will be dispelled. Do please note that it is contrarians who created this confusion and who continue to broadcast it despite the scientific understanding of the role CO2 plays in deglaciation. You get angry about motives and about disinformation and underhand tactics, so you really need to be angry about this. It would be a logical and productive use of your time.
A bit rich given that none of Salby’s recent presentations are based on published work. Furthermore, one doesn’t need to publish something to counter his assertions, one just needs to use the existing literature. He would of course be welcome to comment if he wished to do so.
Not necessarily. There’s no reason for myself and Steve McIntyre (for example) to reach some kind of agreement or to even debate each other. That’s not really how science works. You present your ideas and let others decide. Furthermore, this is just a blog. Whether or not Steve McIntyre and myself ever engage in a discussion or ever reach any kind of agreement is largely irrelevant in terms of climate science itself.
I don’t believe that anything I’ve written would qualify as a character assassination, unless you’re arguing that pointing out that someone’s scientific ideas are wrong qualifies. It may be the case that some comments would qualify, but all those I can think of (John Mashey for example) provide evidence. Providing a link to a public document from the National Science Foundation pointing out financial irregularities with Salby’s funding is not, in my opinion, a character assassination.
I would tend to agree – although I do think pointing out misuse of public money is relevant. What is your view then of Steve McIntyre’s post yesterday in which he presentated various email exchanges involving Robert Way? I think it’s objectionable. I suspect you will find some justification, but you’re welcome to prove me wrong.
not sure why anybody wanted to defend Milankovitch – no problem with him.
So at the end of a ‘glacial’ warming starts in the Antarctic. Not needing CO2 but starts with increased immolation. This warms the southern hemisphere. Reduced ice there, so reduced albedo and an increase in temperature. The Oceans of the southern hemisphere warm and as sea water temperature rises it dissolves less CO2 and releases it to the atmosphere, with a time lag in the southern hemisphere of 800 years (+- 200). Warming occurs throughout the world and further north when ‘it’ ‘arrives’. The Ice in the northern hemisphere begins to decline and the reduced albedo effect accelerates warming. The CO2 levels which have principally increased due to the warming oceans, continue to increase as the oceans warm, but by this time these changes have reached to above the existing arctic circle, the CO2 and temperature levels are in phase. These are then recorded in the ice cores in the northern hemisphere as being in phase. The only problem with this is that correlation does not mean a link exists. Remember on its own CO2 to its maximum will give only a 1 degree or so warming. Remember the Southern hemisphere warmed first and CO2 levels increased after. You still have the problem of showing any noticeable effect from CO2 in what has now become an inter-glacial period.
The Milankovitch cycles dictates the start of the change from glacial to inter-glacial periods – ok no problem with that.
During the interglacial period – what and how long is the time lag between the temperature and the CO2 levels; Worldwide (Ave), in the Northern hemisphere, and in the Southern Hemisphere
There is an assumption that because the immolation calculation does not account for the de-glaciation process, it must therefore be due CO2. How were the calculations on the effect of reducing albedo done ?
Where is the laboratory evidence of positive feedback between CO2 and water vapour in the atmosphere ?
Mike, you seem to be claiming that you can produce the temperature variations during the Milankovitch cycles through solar forcing only. That is incorrect. The Co2 produces an extra forcing that the provide a sufficient forcing to explain the temperature variations during these cycle.
As far as lab experiments are concerned, it depends what you mean. We can’t build a full size Earth. The radiative properties of CO2 and water vapour are quite well known. We also know how the water vapour concentration in the atmosphere varies with temperature. You can’t actually even explain the rise in temperature this century without there having been some water vapour feedback.
The radiation reaching the earth and Not being reflected will increase as the amount of ice reduces. Again has anyone done this calculation. The glacial will have ice coming down from the current arctic and up from the Antarctic, adding quite a bit to the reflectiveness of the earth. The positive feedback of water vapor with CO2 has always been assumed, it would be nice if could finally do the work on it. There were some other questions I asked especially the phasing during the inter-glacial …. any ideas ?
Mike, if you look at Hansen et al. (2011) and consider Fig 4, it shows GHG forcings and surface albedo forcings. It also shows how the temperature variations are consistent with an ECS of 3 degrees per doubling (bottom two panels). So, yes, it has been done. I have seen papers with more detail about this, but don’t have time to find any now. You can probably find others by just considering the references in Hansen et al. (2011).
Mike, as far as feedback is concerned, there’s a fairly simple way to illustrate that it must be operating. Surface temperatures have risen 0.85oC since pre-industrial times. The emissivity of the Earth (including the atmosphere) is about 0.61. This temperature rise should therefore increase the outgoing flux by
F = 0.6 σ (T4 – To4) = 2.8 Wm-2,
where I’ve assumed T = 288.85 K, and To = 288 K.
The anthropogenic forcings have increased by about 2.2 Wm-2 since that time, and solar forcing by about 0.1 Wm-2. If there were no feedbacks, then we’d expect a negative radiative imbalance of around -0.5 Wm-2. Instead, we have a positive radiative imbalance of about 0.7 Wm-2. That means that feedbacks are providing something like 1.2 Wm-2 of radiative forcing.
To be honest, this is a little lower than I was expecting, so maybe I’ve made some kind of silly mistake, but the point is that to explain the rise in surface temperatures since pre-industrial times and the current radiative imbalance, requires that feedbacks must be operating.
No, Mike. As explained earlier the increased insolation (sp!) at Northern Hemisphere high latitudes triggers the process of deglaciation. Do, please, read my original response and Shakun 2012. It’s all in there.
The temperature of the earth has changed many times before and it warmed once before within the last 1000 years alone without mankind’s CO2 being the culprit, and the increase of 0.85 degrees since pre-industrial times starts at a low point at the end of the Little Ice Age. Again what has been so special about the sporadic warming we have had over the last 150 years.
Is “Mike” “Scottish” “Sceptic”? He, and his cohorts, are the only ones supporting Salby’s “science”.
Mike, then there’s physics. Noone is claiming that all changes in surface temperature have to been driven by CO2. However, since the end of the LIA solar forcing has increased by only 0.1 Wm-2. If you want this to explain the rise in temperature then that implies that the climate is incredibly sensitive to changes in external forcings. This should also apply to GHGs. What’s special about the sporadic warming we have had over the last 150 years is that we can’t explain it unless we include anthropogenic forcings which dominate in the latter part of the 20th century (and are not particularly insignificant in the first part either). If you can explain it some other way, please do. Suggesting that it simply recovering from a low at the end of the LIA is not really good enough though.
Ian, I believe that this is a different Mike.
Mike, it would be civil of you to acknowledge your repeated errors at this point.
* * *
There is no evidence for a global, synchronous MCA as warm as or warmer than the present. Even if there were, it would simply confirm that the climate system is moderately sensitive to radiative perturbation. While this might have been a combination of reduced volcanism and increased solar output then, it is a matter of increased radiative forcing from GHGs now. The net effect is the same: warming.
The warming over the C20th cannot be explained in terms of natural forcings. It requires an increasingly large GHG forcing as the century progresses. The climate system doesn’t just warm up and cool down on its own – that would be magic. This requires energy. A change in forcing (energy input) is required to produce a sustained change (trend) in global average temperature.
Ian – Scottish doesn’t muddle up his “immolations” with his “insolations”…
I got the idea that it was the other way round, and this paper says otherwise. The paper (Shakun 2012) has attracted some comment centered around two issues. ‘One is the method of area-weighting to produce a global mean temperature of the 80 proxy sites. The other has been about what the proxies themselves show and it has been suggested that, whilst they all show a rise in temperature since the last glaciation, they do not all have the same timings, and some are not useful at all. Producing an average temperature curve from this sample may not work.
The paper’s figure 2 shows that the temperature increased by about 3.5 deg C between about 18,000 BC and 10,000 BC. During the same period CO2 increased by 70 ppm, from 190 to 260 ppm. Pre-industrial values for C02 are 280 ppm and today they are 390, a rise of 110 ppm. During this time the global temperature has increased by about 0.8 deg C.’
This is nonsense, Mike. Look at the paper. Fig 2 shows a rise of ~2.5C between ~18ka and ~14.7ka, which occurred in tandem with an increase of CO2 from ~180 to ~230ppm. Your source is misleading you.
I should add that you have suddenly forgotten the major influence of ice albedo change (a strong positive feedback) on GAT. Nobody is claiming that the whole change in GAT was caused by CO2 alone.
Mike, a quick comment. The change in forcing due to a change in CO2 is 5.35 ln(C/Co). So a change from 180 – 260 is very slightly greater than a change from 280 – 400 ppm. Furthermore, although we’ve only seen about 0.85 degrees of warming, we haven’t yet reached equilibrium. We’ve probably locked in a further 0.7 degrees. The 3.5 degrees in Fig 2 of Shakun 2012 is partially (about 1.5oC) from CO2 and it’s feedbacks and partially from (I think) an increase in solar insolation. So, no real inconsistency.
Are you saying that the MWP did not exist and that it was as warm if not warmer than present. There have been earlier warming periods
Apologies Mike – I misread your comment about the time-scale of deglacial temperature change and CO2.
It seems to some of you that CO2 is the only game in town.
I did ask one or two other questions – anybody fancy a try …
During the interglacial period – what and how long is the time lag between the temperature and the CO2 levels; Worldwide (Ave), in the Northern hemisphere, and in the Southern Hemisphere
Where is the laboratory evidence of positive feedback between CO2 and water vapour in the atmosphere ? At least Svensmark can do this with cloud formation.
This is what I am saying:
There is no evidence for a global, synchronous MCA as warm as or warmer than the present.
Even if there were, it would simply confirm that the climate system is moderately sensitive to radiative perturbation.
Earlier warming periods? Global, synchronous warming periods as warm as or warmer than the present? Can you provide references in the published paleoclimate literature supporting this claim?
The last time the climate system was as warm as or warmer than the present was ~6ka, during the Holocene climatic optimum, which was the response to orbital (precessional) forcing.
This is not a substantive response to Wotts’ last comment. You aren’t responding substantively to *anyone*. You are just galloping along.
Mike, I don’t know – off the top of my head – the answer to you first question. Although, it does seem that Shakun partly answers it for the last deglaciation.
I don’t know that there is a formal answer to your second. We can’t build a full laboratory of the atmosphere. We do, however, understand how the atmospheric water vapour concentration changes with temperature and do know the radiative forcing due to water vapour. I think I’ve also illustrated (in a comment above) that some kind of feedback must be operating. I don’t think Svensmark can do what you claim he can do, but I’d be willing to be convinced otherwise if you were willing to try. My understanding is that the latest results rule out any major influence from cosmic rays.
Svensmark did, and this was confirmed by the CLOUD experiments at CERN. There has been a continuing trend to ignore or nullify this effect, but it keeps popping back up again.
Somebody, somewhere should have done some work on actually showing this supposed effect of CO2 with water vapour and quantifying it in a lab, please tell me we have not got this far down the road being anti-CO2, decarbonization of mankind etc without this being done.
Actually, no, it wasn’t. Which is why you will be hard pressed to find a reference supporting this claim.
There is in fact no evidence *at all* that the GCR cloud effect has any significant climatological effect.
Mike, maybe you could reflect on the comment. Our own planet is a perfectly reasonable laboratory and I’ve just done a calculation illustrating that feedbacks must be providing around 1.2 Wm-2 of radiative forcing. I also think that BBD is correct. The CLOUD experiment does not confirm Svensmark’s theory. If anything, the latest results make it highly unlikely that cosmic rays play any significant role in global warming.
So Svensmark work is complete nonsense then is it.
Mike, I don’t think anyone here (apart from yourself) has referred to it as nonsense.
I read something recently that challenged Svenmark’s cosmic ray theory. It might have been this paper – Cosmic rays, solar activity and the climate – which found that cosmic rays and solar activity contribute less than 10% of 20th century warming. There’s also this paper – http://iopscience.iop.org/1748-9326/8/4/045022
I also just want to pick up on something you said which is that some of us think CO2 is the only game in town. None of us is saying that.
As for your question about time lag during interglacials, I had a quick search and could only find stuff for the last deglaciation. I found this article – http://www.seas.harvard.edu/climate/seminars/pdfs/Brook_Science_2013.pdf – which says that the last deglaciation is the period for which we have the best data.
Mike, I also think you should read your link very carefully. I don’t think it is saying what you think it is saying.
See Laken et al. (2012)
And Krissanssen-Totton & Davies (2013)
And Sloan & Wolfendale (2001):
There are lots more.
The evidence for the first is simply the saturated vapour pressure of water.
The 2nd sentence is incorrect and alludes to a commonly held misconception on the predicted effect of CO2 and the interplay with water.
The “no feedback” number for doubling CO2 of 1.2 degrees is *not* a prediction of what will happen to the surface temperature. It is merely a convenient way of comparing the magnitudes of different forcings. You *cannot* increase the surface temperature by 1.2 degrees without changing other characteristics of the atmosphere – termed feedbacks.
Some feedbacks (eg clouds) are debatable but water vapour is really not. You would expect, to a first approximation, relative humidity to stay constant. To expect absolute humidity to stay constant (=no feedback) is completely unphysical – given that 2/3 of the earth’s surface is water! That would predict, just for instance, that sea fogs would never happen if the temperature rose.
is a rhetorical construct, *not* a statement of fact.
A statement of fact would be
doubling CO2 will give around 3 degrees or so warming
If you wanted to honestly state the maximum, that would be:
CO2 to its maximum will give only 4.5 degrees or so warming
Except that’s not really an “only”, is it?
The planet is a perfectly reasonable laboratory – well I would beg to differ. How do you isolate some effect from all the rest of the complex interlocking system. You may have a glass jar full of CO2 and show how it absorbs electromagnetic radiation at a certain part of the spectrum and demonstrate the greenhouse effect. The problem is that you then put that CO2 into the climate and do you really understand what is going on. Again where is the research …
The usual cock-ups:
Krissanssen-Totton & Davies (2013)
Sloan & Wolfendale (2011).
If I may speak frankly, what you are doing here is rude. You are ignoring others, repeating errors, refusing to acknowledge errors and constantly moving the goalposts.
verytallguy : and how often do you get 100% saturation in the atmosphere ?
Mike, I think the research is the bit that you’re mostly ignoring. Even you seem to acknowledge that a doubling of CO2 alone will increase surface temperatures by about 1 degree. The calculation I did was to show that, given that knowledge, we can’t explain the increase in surface temperature without some feedbacks operating, and they have to be positive.
Yes, scientists do understand. Please don’t play the “how can we be sure” game here. It’s tedious.
trivially, water vapour is saturated in clouds, fog or inside the boundary layer at a liquid surface. Plus where conditions exist to allow supersaturation – lack of nuclei.
Mass transfer at a liquid surface is given by the difference in the saturated vapour pressure of the liquid and the vapour pressure in the gas phase, typically
C* is strongly temperature dependent
So increasing surface temperature will always drive more water vapour to the atmosphere. Unless you can suggest a reason why mass transfer would reduce.
Now I’ve answered your question, perhaps you could answer one of mine:
Do you agree that
is an honest reflection of the facts whereas
I am not being rude, repeating errors, maybe to you : after all you are so sure of everything.
I did ask a couple of questions, maybe naive of me.
If everybody is so sure of the threat of AGW and its expensive – to put it lightly – remedies, then why have the computer model projections diverged from the measurements ?
You are now doing it again, Mike.
No they haven’t. They’re spot-on. See Global warming predictions prove accurate
Do you agree that
doubling CO2 will give around 3 degrees or so warming
From what starting level? Without any feedbacks; a presence of CO2 will give you an increase in temperature. Keep increasing the level of CO2 and the electromagnetic radiation at those frequencies CO2 absorbs are mopped up. More CO2 gives less and less temperature increase. So with no feedbacks +ve or -ve you get from what I remember (?) a degree or so 1.1C
You have to have the idea of positive feedback or you will not get anything more.
Mike, and I’ve already pointed out that there must already be around 1.2Wm-2 of feedbacks operating.
Maybe I can frame this a different way. I’ve explained in a number of places how we can explain the recent warming and the current radiative imbalance through a small increase in solar forcing (0.1Wm-2), anthropogenic forcings (2.2Wm-2) and feedbacks which would be expected given an increase in atmospheric water vapour (1.2Wm-2). None of this is inconsistent with basic physics. Can you do the same without violating one of the fundamental laws of physics?
How can there be no feedbacks, Mike? Why wouldn’t the warming troposphere hold more WV? All this has been dealt with above, which is what I mean by ignoring correction and repeating errors.
Rachel : you say that ‘No they haven’t. They’re spot-on. See Global warming predictions prove accurate’
I have to disagree with you here. There has been no increase in the worlds temperature for the last 17 years. Climate Scientist’s understanding of the climate was programmed into the models and projections were made with high certainty 90% etc that there would be a continued warming trend. It didn’t happen. The only product of Climate Scientists have been these predictions and they are going wrong. At least with other areas of science you can apply the knowledge, proving beyond doubt that theory is correct e.g transfer genes from one species to another, aerodynamics : design an aircraft like the A380 and it flies etc
Mike, firstly you’re quite conveniently ignoring uncertainties and that such a short time period is not really appropriate for determining long-term trends. Secondly, are you aware of the recent Cowtan & Way study?
“How can there be no feedbacks, Mike? Why wouldn’t the warming troposphere hold more WV? All this has been dealt with above, which is what I mean by ignoring correction and repeating errors.”
I did state in the comment that what I said was without feedbacks. I seem to remember that Lindzen and Choi actually did some work on feedbacks and they concluded that they could go either +ve or -ve
It’s not true that there has been no warming for the last 17 years. In the words of James Hansen, “it has warmed only a tenth of a degree [in the last decade] compared to two-tenths of a degree in the preceeding decade..”
And as Wottsie says above, the new Cowtan & Way study finds this warming has been underestimated. See Missing heat discovery prompts new estimate of global warming.
“Mike, firstly you’re quite conveniently ignoring uncertainties and that such a short time period is not really appropriate for determining long-term trends. Secondly, are you aware of the recent Cowtan & Way study?”
Yes. What strikes me is the remarkable flexibility of climate science. e.g. there have been times when the CO2 levels from man went up and there was a cooling trend over the same period – fears of a new ice etc. A warming trend when CO2 levels did not go up much, and that is in the last 100 years. To me this simply does not add up to a simple CO2 level.
Rachel : Are you seriously saying that things are on track with previous predictions ?
No, there wasn’t. There’s rather a selective recollection of history in some circles though. Why don’t you try responding to my comment asking you to actually try doing some physics to explain our recent warming?
Yep. Myles Allen published a review of a climate forecast earlier this year and showed that is was remarkably accurate. The paper is here – Test of a decadal climate forecast
The forecast so often bandied about on contrarian blogs is one by Ed Hawkins but he has just updated his forecast to include the biases uncovered by Cowtan & Way and it’s looking pretty good now too. See his blog, Updates to comparison of CMIP5 models & observations.
Lindzen & Choi were wrong:
Replies to Lindzen & Choi (2009)/Spencer & Braswell (2009):
Trenberth et al. (2010)
Lin et al. (2010)
Murphy et al. (2010)
Replies to Lindzen & Choi (2011)/Spencer & Braswell (2011):
Trenberth, Fasullo & Abraham (2011)
Now Mike, how about responding to Wotts?
Arguments from ignorance and from personal incredulity are logical fallacies, Mike.
Holocene CO2, CH4 and N2O
And the question I asked you was – how can there be no feedbacks?
You didn’t answer it. When you have responded to Wotts, I would appreciate a considered reply based on plausible physical mechanisms. Or you could conceded the point. I’ve put in quite a bit of time today trying to answer your questions, so a little quid pro quo would be nice now.
well it is 1:35am here in Thailand, despite my PC being on UK time, and I will have to say good night and look at this tomorrow.
sorry but :-
oh what this :-
To me this simply does not add up to a simple CO2 level.
Arguments from ignorance and from personal incredulity are logical fallacies, Mike.
Holocene CO2, CH4 and N2O
FROM THE IPCC WAS IT HAAAAAAA HAAAAAA yeh solid science like the grey literature it quotes
That’s not what I was asking for, Mike, and we both know it.
I think you are wasting your time again. Wotts, this is another good example where you really need to go in and moderate. Demand Mike to respond to the answers to the questions he asks, rather than go off on another thing. Otherwise he’ll just continue his Gish Gallop. Note the comment about the IPCC.
BTW, Mike, ever considered that just about everything McIntyre has put on his blog is not even “grey literature”? Don’t disparage something when you laud something else that doesn’t even reach the level you disparage. It makes you look like a fool.
I don’t think this has been such a waste of time, Marco. I know Mike has just repeated a whole heap of tiresome contrarian comments but I don’t think it hurts to repeat the rebuttals. Other people might learn something from it. I know I have.
His last comment is probably a waste of space though, you’re right there. I think it’s fairly clear to anyone reading who has the stronger argument and that must be useful.
I have to say that I’m impressed with all of BBD’s references. Maybe, BBD, you should put together a goto of climate science references? A sort of anthology of scientific papers.
Thank you for your kind words.
Luckily for me, someone else has already done the work. See Ari Jokimäki’s wonderful AGW Observer for inspiration and guidance.
Neither the be all nor the end all, but a bloody useful reference deserving high praise and wider recognition. Hats off to Ari.
[Rachel: I’ve snipped your comment because you have yet to respond to Watts about feedbacks. Please respond to that first.]
> I did ask a couple of questions […]
You also begged to differ, Mike. Please don’t pretend you’ve only been JAQing off.
It might be time to bring your Gish gallop to a close. If you insist, due diligence will be paid.
I’ve snipped your comment. Please address the comments made to you regarding feedbacks.
Wow! That’s amazing. Thanks for sharing that. It does need wider recognition.
Perhaps you are right after all. Still trying to figure this out.
Rachel, the main problem with Gish Gallopers is that many people will get frustrated and respond less than constructively. I myself will do that on occasion. This is where demanding the person (Mike in this case) to finish the discussion on a point before being allowed to bring in a new point will help.
Yes, I can certainly see some frustration mounting here. Wotts and BBD have put in quite a bit of time and effort in responding to Mike, which when this gets ignored, is particularly frustrating.
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Rachel : If you are really saying that there has been no standstill in temperature since the late 1990’s, then perhaps we should leave it at that. In the end the facts will do the job, there is no point in debating further. I’ll try to respond to the feedback issue a little later.
Yes, Mike, let’s leave it at that. It’s not just about temperature of the atmosphere. It’s heat accumulation in the whole earth system. There’s no “standstill” in the latter at all.
Mike, given that the GISSTEMP trends are 0.08 +- 0.131 degrees per decade (1997), 0.068 +- 0.144 degrees per decade (1998) and 0.103 +- 0.155 degrees per decade (1999) I don’t think one can claim there’s been a standstill since the late 90s.
As Marco says, concentrating (as contrarians invariably do) on tropospheric temperatures is actually a shameless cherry-pick!
OHC 0 – 2000m
There is no slowdown, hiatus or pause in the rate at which energy is accumulating in the climate system as a consequence of radiative imbalance forced by the rise in atmospheric concentrations of GHGs. Transient variability in the rate of ocean heat uptake appears to be playing a major role in the temporary slowing of the rate of tropospheric warming. Perhaps the only significant effect this has had is to bias several recent “observational” estimates of climate sensitivity low.
Yes, I’ll also add to what BBD and Marco have said. In my previous comment, I should really have said “in addition to the clear evidence that the climate system continues to accrue energy, one still cannot really claim that there has been a slowdown in surface warming since the late 90s”.
“Mike, given that the GISSTEMP trends are 0.08 +- 0.131 degrees per decade (1997), 0.068 +- 0.144 degrees per decade (1998) and 0.103 +- 0.155 degrees per decade (1999) I don’t think one can claim there’s been a standstill since the late 90s.”
You have got to be joking; so when the data doesn’t do what you want, don’t honestly report the reading year by year because it shows no further increase, simply choose 10 year averages at suitable points to make it look as if the temperature is still increasing. Didn’t Kevin Trenberth say in the one the climategate emails here he is quoted by another scientists :-
“These sums complement Kevin’s energy work.
Kevin says … “The fact is that we can’t account for the lack of warming at the moment
and it is a travesty that we can’t”. I do not”
“Yes, I’ll also add to what BBD and Marco have said. In my previous comment, I should really have said “in addition to the clear evidence that the climate system continues to accrue energy, one still cannot really claim that there has been a slowdown in surface warming since the late 90s”.
So the climate system continues to accrue energy, so where is it ? According to K Trenberth it has sneaked off and hidden deep in the oceans .. somewhere, but he can’t show where ! good luck to him on finding it – maybe he’ll find it before Svensmark finishes his work.
Another ‘theoretical’ explanation for this missing heat is that it could be it has vented from the earth’s atmosphere and it is not being accrued.
Still working on that feedback response ….
Mike, I didn’t use 10 year averages. Those are the trends up until 2013 starting in 1997, 1998, and 1999. I simply calculated what you claimed. You claimed there had a standstill in warming since the late 90s. Maybe you can try actually showing that, rather than simply making a claim without any evidence.
You’re waiting for a feedback response? I’m waiting for you to notice it. I’ve responded more than once. Just because you don’t understand the response, doesn’t mean it isn’t one. I’m still waiting for you to respond to my question about you explaining the ongoing warming in a way that doesn’t violate the fundamental laws of physics.
If you don’t believe the OHC data, that’s your right. Pretending it doesn’t exist, on the other hand, is harder to justify. That would appear to be ignoring reality.
Concerning the references BBD posted. I do not have an academic sub for these and one link doesn’t bring up anything. One I do have access to :-
“A Determination of the Cloud Feedback from Climate Variations over the Past Decade
A E Dessler”
This is interesting as while it sticks with the feedback must overall be positive line it admit that feedback can be negative, also from the following the author is honest to admit that they don’t know :-
“For the problem of long-term climate change, what we really want to determine is the cloud feedback in response to long-term climate change. Unfortunately, it may be decades before a direct measurement is possible.”
Estimates of Earth’s climate sensitivity are uncertain, largely because of uncertainty in the long-term cloud feedback. I estimated the magnitude of the cloud feedback in response to short-term climate variations by analyzing the top-of-atmosphere radiation budget from March 2000 to February 2010. Over this period, the short-term cloud feedback had a magnitude of 0.54 ± 0.74 (2σ) watts per square meter per kelvin, meaning that it is likely positive. A small negative feedback is possible, but one large enough to cancel the climate’s positive feedbacks is not supported by these observations. Both long- and short-wave components of short-term cloud feedback are also likely positive. Calculations of short-term cloud feedback in climate models yield a similar feedback. I find no correlation in the models between the short- and long-term cloud feedbacks.
For the problem of long-term climate change, what we really want to determine is the cloud feedback in response to long-term climate change. Unfortunately, it may be decades before a direct measurement is possible. In the meantime, observing shorter-term climate variations and comparing those observations to climate models may be the best we can do. This is what I have done in this paper. My analysis suggests that the short-term cloud feedback is likely positive and that climate models as a group are doing a reasonable job of simulating this feedback, providing some indication that models successfully simulate the response of clouds to climate variations. However, owing to the apparent time-scale dependence of the cloud feedback and the uncertainty in the observed short-term cloud feedback, we cannot use this analysis to reduce the present range of equilibrium climate sensitivity of 2.0 to 4.5 K.”
Again where is the real evidence that the feedback is overall positive ?
The answer is we really don’t know.
There appears to be an assumption that water vapour and CO2 provides a positive feedback. Where is the actual experimental science showing this. I do ask the question as Svensmark is in the actual process of working on the cosmic ray link to albedo on earth. But it looks as though BBD will not countenance its effect – probably until the IPCC finally admits it. So we have one ‘effect’ being investigated and ignored. While the other has not been experimentally demonstrated and is accepted because it is crucial to justify the whole AGW circus.
Don’t you think there is something a bit odd with this
Mike, I think you should probably go and read that paper more carefully. I don’t have a chance to do so myself at the moment, but I don’t think it is talking about overall feedbacks. I think it is only referring to clouds. If you really do want to engage on this thread, why don’t you actually read that paper properly and then report back as to whether or not it is relevant to the discussion and maybe give us a brief summary of what it actually says.
See, here we go with Mike’s gish Gallop again, deliberately abusing Trenberth’s comments. There simply is no way for someone who so easily comes up with all these talking points to not have noticed Trenberth’s response to the abuse of this comment, and therefore I call it a deliberate abuse. Mike, own up that you have deliberately taken the comment out of context and therefore by proxy lied about what Trenberth said. Be a man!
For those who read along and don’t know what Trenberth had to say, see the link below:
http://www.cgd.ucar.edu/staff/trenbert/emails/ (last part)
“It is amazing to see this particular quote lambasted so often. It stems from a paper I published this year bemoaning our inability to effectively monitor the energy flows associated with short-term climate variability. It is quite clear from the paper that I was not questioning the link between anthropogenic greenhouse gas emissions and warming, or even suggesting that recent temperatures are unusual in the context of short-term natural variability.”
Can anyone confirm that CO2 lags temperature during the interglacial world-wide …
[Rachel: This is clear misrepresentation of someone’s private correspondence. Let’s stick with feedbacks, Mike.]
I really must be misinterpreting what I’m reading. So what exactly do you think it says ? (I would be interested in your opinion)
As I said that was the only one I could read, without dishing out cash. It was quoted by BBD ? to counter Lindzen and Choi. with their paper saying the feedback could go either way
No it is not. Lets stick to the fact about this. If you have been indoctrinated to believe anything you are being fed by the AGW supporters, then that is up to you, but do not pretend that this cessation of warming does not exist.
There is no indoctrination here, Mike. There are measurements and observations of surface temperatures going up, ocean heat content going up, ice melting, sea level rising….there is no cessation of of warming.
Rachel, the clincher of course is the TOA energy imbalance where we can measure and show that there is less heat (energy) being emitted than is received from the sun.
Fine Rachel, you believe what you want to.
Thanks, Ian. I have thoroughly enjoyed reading your comments at Scotty’s btw 😉
Mike clearly cannot be bothered to read my comments. Or why would he say this:
This link will take you back to the comment you did not read. Within that comment you will find a link to the ocean heat content data for the 0 – 2000m ocean layer. Click that link and look at the graph.
IMO you are a time-waster or a data-denier, or both.
I posted abstracts because I did not and do not believe you would bother to read them. However, perhaps I was wrong. Here are the full papers:
Replies to Lindzen & Choi (2009)/Spencer & Braswell (2009):
Trenberth et al. (2010)
Click to access trenberth2010.pdf
Lin et al. (2010)
Click to access acp-10-1923-2010.pdf
Murphy & Forster (2010)
Paywalled, but there’s a discussion at Science of Doom here:
Click to access dessler10b.pdf
Replies to Lindzen & Choi (2011)/Spencer & Braswell (2011):
Click to access Dessler2011.pdf
Trenberth, Fasullo & Abraham (2011)
* * *
WRT cloud feedback, here is a simple demonstration that even if it is weakly negative it does not *dominate* the climate system. If it did, what do you think would happen when a forcing increased? It doesn’t matter if it’s solar, or TSI modulated by a reduction in volcanic aerosols, or an increase in GHGs. Just any forcing increase.
If negative cloud feedbacks dominate the climate system, would it:
a/ Warm up
b/ Cool down
c/ Stay the same
You have a careful think about that.
Isn’t there supposed to be a time lag between any warming of the earth and the oceans catching up with it.
This might explain what you see here. In other words leave it a few years and it will stop increasing and flatten out.
The warming effect is lagged in the sense that it takes centuries for the climate system to reach full equilibrium. If no more CO2 were emitted from today, GAT would rise a further ~0.6C.
I don’t know why you are going on about this. The apparent lag during deglaciation is confined to the SH and you have already had a detailed explanation of why this happened. Please review the thread.
Please, before we move on to the way GHGs slow down the rate at which the oceans *cool*, let’s just go back a bit.
First, you can say, “thanks for those links, BBD, much appreciated”. That’s the civility bit out of the way.
Then, you can address yourself to the a/ b/ c/ question above and hazard an answer.
Oh, and what about the OHC data?
Do you accept that there’s no “missing heat” or do you deny the validity of the OHC data? If you do, you will have to explain – in convincing detail – why.
Mike, you’ve come here and accused people of being indoctrinated. You can either put some effort into showing that there’s been no warming (and “I don’t trust the data” is not going to be good enough), you can very explicitly retract that statement, or you can be banned. I don’t really care which option you select.
Er give me a chance to respond please … People were making comments about how long it was taking me to respond – I was waylaid with other things and trying to do some reading, and I think some of my posts were not put on the site …
So you have given me access to the full papers now well ok thanks for that. I’ll have a read.
Concerning the feedback effect of cloud – probably say -ve but there are different types of cloud, and the feedback could depend on water saturation etc etc ( trying to interpret consequences of single elements in a huge and complex system)
I found a couple of papers referenced in a book called Chill by Peter Taylor about albedo – will take some time to write it up.
I’ve read Chill. Peter – though a nice chap with some interesting ideas about rewilding – is largely mistaken about climate. Rather than starting with Chill, why not read a proper climate textbook?
Now, if cloud feedback is negative and *dominates* the climate system to the extent that it is the major determinant of climate behaviour when the system is forced, what will happen when a forcing is increased
Will the climate system:
a/ Warm up
b/ Cool down
c/ Stay the same
You are the one proposing that feedbacks net negative, so please apply your reasoning to this question.
Mike, while you’re thinking, you could still retract your claim of indoctrination. That shouldn’t take much.
Ban me from the site – you know it is entirely up to you. I call someone indoctrinated; I think they are. Some of the comments about me and what I have written I have not complained about, and you did not seem concerned. What has struck me is that members of this site are to put it mildly, touchy and looking for any excuse to take offense, or perhaps to me it all seems rather synthetic.
My only complaint was in defense of another individual SALBY – he is not someone I know – you may recall it a few days ago. Some of the links included by some of your contributors to other sites included much personal information used to denigrate him – I suggest you go and check.
Ahem. Come on, Mike.
Will the climate system:
a/ Warm up
b/ Cool down
c/ Stay the same
What’s the problem? Why no answer?
Mike, why don’t actually try responding to what people say. You claimed that people used personal information to denigrate Salby. All I can remember is John Mashey linking to an NSF document that referred to financial irregularities associated with Salby’s funding and Mashey also pointed out that Salby had been banned from applying for NSF funding. Is this what you regard as a personal attack?
When I responded to that point, I also asked you what you thought of Steve McIntyre’s recent post in which he highlighted a number of emails involving Robert Way. Robert Way clearly (based on his own comment on that post) regarded these emails as private and objected to them being posted. Are you willing to comment on that?
-Ve feedback : So if we have fluffy white clouds and they reflect energy from the earth then an input of energy to the earth and its atmosphere has been reduced. This effect – if it exists – goes into the climate soup. The things that make the earths climate so changeable on a day to day basis : call a meteorologist to explain further.
Mike, you could try reading this post and, in particular, the paper by Stephens (2005). I think this is quite well understood.
Mike, you could also try answering the questions I posed in my previous comment and also those from BBD. I also recognise that I haven’t insisted on you retracting your indoctrination claim, or back up your no warming claim. I’d like you to do consider doing one of those too.
The link posts about Salby were unacceptable if this site is trying to ‘Trying to keep the discussion civil’.
After the release of the climategate emails; quite frankly I was appalled.
“When I responded to that point, I also asked you what you thought of Steve McIntyre’s recent post in which he highlighted a number of emails involving Robert Way. Robert Way clearly (based on his own comment on that post) regarded these emails as private and objected to them being posted. Are you willing to comment on that? ”
I’m sorry to say but after what I read of the CRU emails and followed the shenanigans of some climate scientists I think McIntyre’s tactics are justified, especially after some of the stuff that has been tried on him. It’s a bit like being a civil libertarian and then having extremists conducting terror attacks : you finally accept the need for an intelligence service.
Mike, I fail to see how pointing out that someone misused public money has anything to do with being civil.
I also fail to see how emails from the 90s should justify Steven McIntyre posting private emails from a young PhD student today.
I’m starting to lose patience. Either provide evidence that there’s been no warming, retract your claim of indoctrination, or go away. My preference now is the latter given that I really have no actual interest in engaging with someone who thinks that what Steven McIntyre did with regards to Robert Way’s emails is in any way acceptable.
Why are you consistently refusing to answer the question I asked you about cloud feedback? The purpose of this exercise is to examine the hypothesis that cloud feedbacks are strongly negative and dominate the climate system response to forcing. The necessary first step is that you engage. So once again, please answer the question. Assuming cloud feedback to be negative and climatologically significant, if a forcing is increased (eg TSI; GHG) will the climate system:
a/ Warm up
b/ Cool down
c/ Stay the same
Sorry about the usual crossing. I suspect that Mike is hoping that by antagonising you he will be banned without having to retract his false claims or respond to various studiously avoided questions.
It’s working 🙂
Gin & tonic? 😉
I’m trying the gin & tonic route, but it’s not working this time 🙂
You are starting to lose patience with me !!!!!!!!!! Who the do think you are ? The site went into SALBY’s divorce and marital dispute etc pretty shitty tactics if you ask me.
You start a web site looking like a clone of a far more reputable and successful one with opposing views; obviously trying to deceive people into reading your AGW supporting material instead. Why didn’t you have one that was not a carbon copy look alike eh ? oh dear that might be being honest.
Your contributors are intolerant of anything that disagrees with them – as I have experienced.
The line of ‘debate’ is very similar to that I’ve had with from those of the AGW religion, just never ever dare to disagree or test them on anything, even if you believe some of what they say. It is a pity, you might actually have achieved something if you were not so set in your agenda. Some of you just can’t walk the walk on debate.
Mike, go away.
By the way, as far as I’m aware, it did not. If you can find a comment or post that mentions this I will delete it. You are currently in moderation, but I’ll still happily delete anything that mentions his divorce or marital disputes.
Good luck with your web site – you will need it. I’m back to the real wattsupwiththat
Those links about Salby have been up for some time
Mike, you said
Where? You could use this to show that you are actually capable of providing evidence to support what you say. Call it a test, if you will.
The perfect gin and tonic:
Pour a generous splash of Plymouth gin in a tall, straight-sided glass. Add plenty of ice (cubed, not crushed) – fill the glass about a third full. Squeeze a wedge of lemon over and discard. Fill the glass to slightly over two-thirds with refrigerated, freshly-opened and very fizzy tonic. Trust me. This is how it’s done.
BBD, that sounds perfect. Dangerous, but good.
What about the answer?
What ever is the problem?
Live a little Wotts. You’ve earned it.
Wotts, Mike is likely mixing up things. John Mashey, in his documentation of all that happened to Murry Salby, indeed also mentions divorce proceedings. As John notes:
“Salby was earlier involved in complex divorce proceedings, relevant here only because there seemed to be financial issues and possibly attempts to hide money, consistent with NSF findings:”
But, as I already warned would happen, it’s another nice squirrel Mike throws out to not have to respond to the answers that demolish his pseudoquestions (claims masked as questions and vice versa).
Marco, thanks, after some searching I managed to work that out. Hence, it’s rather frustrating to have Mike claim that this site went into Salby’s divorce …. The first time Salby’s divorce was mentioned on this site was when Mike did it himself. The only reason it’s being discussed now is because Mike mentioned it. As you point out, it probably does illustrate what some will do to avoid actually addressing what’s being discussed.
Wotts, as you have found the relevant link, no need to specify it. The wording of the link, ie, “Interesting background on Salby” is itself entirely innocuous. The discussion of the divorce in the link starts by saying, “Salby was earlier involved in complex divorce proceedings, relevant here only because there seemed to be financial issues and possibly attempts to hide money, consistent with NSF findings” True to that introduction, it only discusses the financial aspects of the divorce as revealed by court documents, and mentions that Sably sued the state for violation of his constitutional rights because the court ordered division of property. In other words, it entirely avoided personal discussion of the divorce. Mike’s faux outrage is, therefore, entirely unwarranted. The entire rant is just him working himself up to justify his running away from a loosing argument without having to admit he lost.
What did you do with my final post ? You could at least post it.
Why? You’ve come here and accused people of being indoctrinated and refused to either retract that or back it up with evidence. You’ve claimed, incorrectly, that this site went into Salby’s divorce. You’ve failed to answer most of the questions that were aimed at you. You’ve failed to acknowledge when others have attempted to answers questions from you. Why should I possibly post any further comments from you? You have one more comment to convince me that I should change my mind.
Goodbye – although the books and material I included did act as a response, and obviously they are not my work, but it is what I base my opinions on. Also on the matter on phase difference between CO2 and temperature – has anybody going to admit that in the interglacial periods the CO2 does lag temperature.
Goodbye Mike. If it were definitely true, I would happily admit it. Given that I think it is not true globally (Shakun 2012) then I see no reason to do so.
Now have some time back : I was just trying to read your links; this one still doesn’t work:-
Click to access trenberth2010.pdf
Also can you please include the pdf/links for correspondence from the other end from Lindzen etc. Thanks in advance – this is just out of personal interest.
Here’s the correct link to the paper you requested: Relationships between tropical sea surface temperature and top-of-the-atmosphere radiation
If you visit AGW Observer, you might be able to find the other papers yourself.
You never answered the question about cloud feedback. The purpose of this exercise is to examine the hypothesis that cloud feedbacks are strongly negative and dominate the climate system response to forcing. The necessary first step is that you engage. So once again, please answer the question. Assuming cloud feedback to be negative and climatologically significant, if a forcing is increased (eg TSI; GHG) will the climate system:
a/ Warm up
b/ Cool down
c/ Stay the same
Can I say “troll” at this point?
I’d prefer it if you didn’t. Mike’s comment went through moderation and I thought it might be useful to correct the link, if not for his benefit, then for other people reading the thread. Let’s give him the benefit of the doubt and assume that he might actually be interested in reading the scientific literature.
It is Mike’s serial refusal to answer a relevant question that prompted me to call a spade a spade. IMO the tail is wagging the dog here.
Ech. Sorry. And thank you for fixing my broken link.
BBD, it depends on whether the goal is to get Mike to answer the question, or to illustrate to others that Mike seems unable/unwilling to answer the question 🙂
It could be that Mike wants to do some reading before answering the question 🙂
On the matter of Shakun et al. I think this probably deals with it from Nir Shaviv, he wrote this some time ago – I’m surprised the original paper is still getting people excited. Also none un-manipulated data from the ice cores shows CO2 lagging temperature :-
“Given the fact that the global temperature is composed of the SH and NH and that one precedes and the other lags the CO2, is there any meaning to averaging the two? Perhaps not if the physical behavior is different (at least for the particular temporal window studied in their paper). Even so, one would imagine that such an average for the global temperature should be half of the NH and half of the SH. This is because, at least last that I checked, exactly half of the Earth’s surface area is in the Northern hemisphere and half is in the southern hemisphere (unlike comparison of the land area, or the temperature proxy data in the Shakun et al. paper).
With this in mind, I started playing with the data. I was utterly surprised to learn that in order to recover their average “global” temperature, I needed to mix about 37% of their southern hemisphere temperature with 63% of their northern hemisphere temperature. In other words, their “global” temperature is highly distorted towards the Northern hemisphere! It is therefore no surprise that once they do find a northern hemisphere temperature lag, also their global temperature exhibits a similar lag, but it is not a global temperature by any means!
My suspicion is that the authors have a different averaging weight to the two hemispheres because of the asymmetry in their data distribution, however, their global temperature is close to but not exactly the ratio in the number of datasets in each hemisphere, so I don’t actually know what they did.
Together with the faults pointed out by other people (most notably on WUWT), the Shakun et al. paper should not be considered as anything which proves that CO2 has a large effect on climate. My prophesy, though, is that the Shakun et al. paper will become a major hallmark in the next IPCC scientific report. This is because the alarmist community needs it badly as evidence that CO2 has a large effect of climate. They will also ignore all the major flaws which exist in it, because it will be convenient for them to do so. I hope I’m wrong, but I feel I’m right, and not only because one of the co-authors on the paper is also a lead author of the upcoming IPCC AR5 report.”
Did it appear in AR5 in the end ?
Still reading (once you start it never seems to end) … … Went to the IPCC to see what it said : WORKING GROUP I CONTRIBUTION TO THE IPCC FIFTH ASSESSMENT REPORT
CLIMATE CHANGE 2013: THE PHYSICAL SCIENCE BASIS
Click to access WGIAR5_WGI-12Doc2b_FinalDraft_Chapter07.pdf
Reading 7.2.X.X about feedbacks; what is interesting is that so much of the conclusion about it in favor of there being net positive feedback was from papers relying on theory and computer models.
Mike, you do realise that what you’re reading refers only to clouds. There are other feedbacks. Theory and computer models, that’s kind of a big part of how science works. Even if you have some measurements you still need a calculation/model/theory in order to understand what your measurement is telling you. As you acknowledge, at least, the general view at the moment is that clouds provide a small net positive feedback due to a doubling of CO2.