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HumanityRules at 10:27 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
13.GFW That seems like a fairly static understanding of the processes. Surely anything in a process in transition can act as a driver for other aspects of the system. It's about cause and effect. At the moment we see CO2 being pumped into the system by us and ask what secondary affects is this having. If other things are changing under their own control these can then be generating their own feedbacks. For example the evolution of life and later green plants and their spread across the planet had a huge affect on atmospheric chemistry and all the subsequent effects that had on climate. In this case bacteria, plants and animals are the driver of change, generating their own feedbacks and CO2 becomes a feedback at this moment. So specifically in the Pliocene why shouldn't the geological changes be driving changes in climate directly. Certainly the joining of N and S America seems to have had massive repercussions on ocean circulation it's impossible to imagine this didn't have an affect on climate which would resolve itself over many timescales 11.Marcel Bökstedt I don't doubt all these processes resolved themselves over a much longer periods but it does seem that the Pliocene is often described as a mountain building epoch. We seem to accept that mountain building and tectonics could have a significant affect on CO2 why not other aspects of climate. This is a dominant process of the epoch. I've still not read anything here that rules out this as a driver of aspects of climate, I'm happy to find the big hole in my understanding. Again as an example the continued rise of the Himalayas must have had huge affects on the hydrological system of the regional and all the subsequent affects on vegetation, rivers, erosion and the like. Another description of Pliocene here http://www.enotes.com/earth-science/pliocene-epoch -
Tom Dayton at 09:48 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
If anyone else wants to reply to skepticstudent's comments about water vapor as a forcing, will you please do it over at Water vapor is the most powerful greenhouse gas? skepticstudent already has been pointed in that direction, so he should be reading that thread. If you want to get his attention on this thread, how about posting a short comment telling him your substantive comment is over there? -
Rob Honeycutt at 09:47 AM on 10 May 2010Climate Change and the Integrity of Science: a letter to Science
@Steven Sullivan... Your reference is really interesting but I would suggest that we're likely charting very new territory here on this issue. Can you think of a time when the media had as much influence on driving opinions that are counter to the mainstream science? Maybe with Darwin? There have been times when science was coming to conclusions that were not politically convenient and have come up against the establishment, so nothing new there. I think there are some ways to consider what is going on now that is both similar and very different from the past, that could potentially be very helpful to addressing the looming problem. What concerns me most is what I see happening in terms of potential damage to the whole scientific process. -
yocta at 09:47 AM on 10 May 2010Over 31,000 scientists signed the OISM Petition Project
As the Policy on Comments and Replies states: ...Both Comments and Replies will be refereed to ensure that the Comment addresses significant aspects of the original paper without becoming essentially a new paper... Notice how the word "comment" is in the title? You have to be careful with your language when using words such as 'refute' and 'challenged in the peer-review literature' when informing the readers on SkepticalScience as it is highly speculative language. If a new survey and hence a new paper was performed with results contrasting Doran and Zimmerman then you could say 'challenged in the peer-review literature'. At the moment all you can say is their are two published criticisms of the paper, and that the author replied to these. With your actual concerns over the survey, that the two critics made, the EOS is behind a pay wall so it would be difficult to discuss the actual contents and author's reply further unless somebody with a subscription can access the content. Also where do you get the number from Doran 2009 that 567 Scientists Surveyed do not believe man is causing climate change? -
Marcus at 09:37 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
Ah, SS, you're falling for the oldest trap in the book. It's true that water vapor accounts for around 60% of the planet's *natural* greenhouse effect (i.e the roughly 33 degrees C between the planet's average temperature of +15 degrees C & the -18 degrees C it would be without *any* greenhouse gases), whilst CO2 "only" accounts for 20%. However, water vapor accounts for between 1%-3% of the atmosphere. By contrast CO2 accounts for about .04% of the atmosphere-which of course makes CO2 a significantly stronger greenhouse gas-on a ppmv basis than water vapor. 2nd is the fact that individual water vapor molecules have a significantly shorter residence period in the atmosphere than CO2 (days to weeks compared to years to decades). 3rd is that water vapor contributes to both greenhouse effect & albedo wheras-to the best of my knowledge-CO2 contributes nothing to albedo-only to greenhouse effect. Thus its easy to see why CO2 is a driver, but water vapor is only a feedback. -
Steven Sullivan at 09:26 AM on 10 May 2010Climate Change and the Integrity of Science: a letter to Science
lost in edit: "where the view of a single or few 'eminences' over-influenced the mainstream view" -
Steven Sullivan at 09:25 AM on 10 May 2010Climate Change and the Integrity of Science: a letter to Science
omnilogos, I can cite easily cite examples from the history of science where the 'mainstream' view was later overturned, or where the view of a single or few 'eminences' the mainstream view. (There's a fine example in the early history of malaria research, for example, where the mistaken claim of an eminent parasitologist misguided the course of research for decades.) Now all you need to do is establish that this is what's going on in year 2010 climate science, which is not exactly in its infancy, is not controlled by the view of one or a few scientists, as has vocal 'skeptics' publishing peer--reviewed work (e.g, Pielke Sr., Lindzen, Christy). -
Rob Honeycutt at 09:22 AM on 10 May 2010Kung-fu Climate
I have to agree with JMurphy saying that it's probably not worth engaging Poptech on this site. What I see going on is, he plays my his own rules except when they are used to counter his position, then there are another set of rules. I think it's really bringing down the quality of the discussions here on John's site. -
Rob Honeycutt at 08:26 AM on 10 May 2010Climate Change and the Integrity of Science: a letter to Science
@skepticalstudent... I'd also highly suggest that you take one issue at a time and edit your posts for brevity. -
Rob Honeycutt at 08:25 AM on 10 May 2010Climate Change and the Integrity of Science: a letter to Science
@skepticalstudent... Maybe you should consider a different approach to presenting what you have to say. Many times frustration comes not from what someone says but how they say it. I can definitely see the frustration from those engaging you in this conversation. You seem to assert positions and cite little to back it up. Most of the people here are working scientists. Teachers. If a student turns in a paper making a lot of statements (like "it's the coldest since 1775") without backing it up somehow, that student would get a failing grade. If you are indeed a "skeptical student" rather than a "student of skepticism" then I would suggest you slow down with the rants and listed to criticism of your statements. Do what a student does. Learn. -
Marcel Bökstedt at 08:18 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
frogstar> It seems that they base the analysis on preliminary work on pliocene vegetation like: Salzmann,U. , Haywood, A.M.,Lunt, D.J.,Valdes, P.J.,and Hill, D.J.(2008).A new global biome reconstruction for the Middle Pliocene. Global Ecology and Biogeography, 17, 432–447. In that paper, the main result seems to be that they partition the Earth of that period into 27 vegetation zones like "desert" or "open conifer woodland" etc. I don't believe that they speculate on how evolution might have adapted plants to higher CO2 levels. -
Jim Eager at 08:00 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
skepticstudent is indeed 'just sayin'. Rather than 'just sayin' skepticstudent needs to do some actual studying. If he were to do so he would learn all the reasons why he doesn't have a clue what he's 'just sayin' about. Such as the very reason that CH4, N2O, O3, CFCs and the other purely man-made less common greenhouse gases are more potent than CO2 is precisely due to 1) their being so much less common: doubling them requires adding so much less of them to the atmosphere, times 2) their life in the atmosphere. Such as although those gases are more potent than CO2, meaning they have a much higher potential for influencing earth's radiative balance, the 38% and growing increase in CO2 dwarfs their combined increase by sheer volume. Such as the fact that water vapour, the one greenhouse gas in greater supply than CO2, by a factor of 10, can only act as a feedback to some initial change in temperature of the atmosphere, what ever the cause or sign of that change, while CO2 can act as either a feedback to an initial change in temperature, OR as an initial forcing when added to the atmosphere independent of an initial change in temperature. Such as the fact that the 'water' is currently a net absorber of CO2, which is why ocean surface pH is falling as CO2 increases in the atmosphere. -
batsvensson at 07:47 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
skepticstudent at 05:47 AM on 10 May, 2010 "how could co2 be a "driver" and the others which are far more powerful be mere feedback" It has to do with 1. the life time, 2. the concentration and 3. the scattering frequencies of these gases in the atmosphere. The three most common gases in the atmosphere Oxygen, Nitrogen and Argon, if I recall right now, do not absorb outgoing long wave radiation, but do scatters radiation in the incoming spectra (hence creating a blue sky by means of incoming scattered short wave radiation). All other gases are traces gases but the most abundant of them is CO2. CO2 – simply put, once there it stays there (I am deliberately ignoring the carbon cycle here). Methane, another trace gas, is broken down to CO2 and water vapor after a while and thus contribute to more CO2. Methane concentration is also significant lower than CO2 concentration, by a factor 200 about. Methane I believe is about 20 to 30 times more potent as greenhouse gas but far less abundant and not very long lived, therefore its effect fades compare to CO2. Methane can have a strong short term effect if pumped out in massive amounts but due to it short life time its effect will go away within a decade or so and be replaced with a long term effect from CO2. Water vapor, perhaps the most potent greenhouse gas, has its own life and its concentration varies by god know what and how many factors and it tends to crystallize and fall out now and then. Water and its vapor is an important substance when it comes to transport heat around, in seas as in air, and its vapor has an great effect on the greenhouse effect – when it pleases to be present that is - but its behavior is erratic and the understanding of water vapors life cycle and it effect on global warming is poor at best. For the rest of the trace gases they do simply not contribute significantly to the energy balance. Does this motivation make sense for you? -
thefrogstar at 07:46 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
How are the effects of flora modeled in these paleo-climate reconstructions? As a reult of the impact of growth and death on CO2 and methane levels, I would expect the effects to be significant. The increase (and decrease) of living agents is (by definition, I would argue) exponential in nature. And this is without factoring-in any Darwinian selection processes such as, say, selection for flora that are better able to compete at higher concentrations of CO2. Do paleo-climate reconstructions have the kinetic-resolution to adequately describe such changes? I whould hazard a guess that small photo-synthetic organisms do not leave leave much of a trace in the fossil record irrespective of their genome. -
johnd at 07:30 AM on 10 May 2010Climate Change and the Integrity of Science: a letter to Science
tobyjoyce at 23:25 PM, the use of the word "you" was not directed at you personally, perhaps it would have been better I had used the word "one" instead. The use of the word is no indication of my demeanour, merely how is is generally used amongst my peers. Political correctness often catches us out and I apologise to those who are sensitive to such gaffs. Obviously in the first paragraph, and in the last sentence, the you does refer to, well, you. -
tobyjoyce at 07:29 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
@Tom Dayton, Thanks, that's given me some good reading From tamino's blog. Very helpful. -
tobyjoyce at 07:25 AM on 10 May 2010Climate Change and the Integrity of Science: a letter to Science
@scepticstudent #172, A friend of mine once told he saw a drunken man bang his head repeatedly against a stone wall "to show what a brave man could do". I hope you agree that there are different types of courage, and sometimes faintness of heart is a Darwinian advantage. On the substantive point, or points (I lost count),I am going to kick for touch, and refer you to another part of this blog, where you can comment as you wish: Broken Hockey Stick -
kdkd at 07:20 AM on 10 May 2010Kung-fu Climate
Poptech #216Computer models can be useful in engineering and design.
You appear to be implying that this is the only situation that computer models are useful in, although you haven't answered all of my question. That perception is rather far from the scientific consensus on modeling of stochastic and complex systems. I'm afraid that as you have implied that modeling is not useful in any situations, then you are suggesting that a large proportion of the modern sciences in biology, psychology, meteorology, medicine, and elsewhere is not valid. As much of the infrastructure of civilisation is based on this "soft" modeling, your position appears to be little related to the reality of the situation. -
Philippe Chantreau at 07:07 AM on 10 May 2010Kung-fu Climate
Well, looks like I'm going to recant on my promise about Bond events but, to my defense, I'll say that it is because the connection between Bond events and Loehle's reconstruction deserves some attention, would it be only because Poptech advocates for both. This poses a problem, since, from cursory inspection, their respective realities do not match very well. The most recent Bond event has been dated approximately 1400 years BP, possibly from 450 to 900 AD (Bond 1997) but with a peak at about 600 AD, where Loehle shows a postitive anomaly of 0.3C, among the highest in the entire graph. -
Tom Dayton at 07:01 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
Skepticstudent, go to the Search field at the top left of the page. Type "water vapor feedback" and hit the Go button. In the resulting list, click "Water vapor is the most powerful greenhouse gas." If after reading that post and the comments you still have questions, ask on that thread, not this one. -
Riccardo at 06:51 AM on 10 May 2010Climate sensitivity is low
The problem is that Spencer keeps repeating the same wrong conclusions in his blog ("These results suggest that the sensitivity of the real climate system is less than that exhibited by ANY of the IPCC climate models. ") so that they're still usefull for the skeptic community. I prefer not to comment on this attitude that he has in common with other (luckly few) skeptic scientists. -
Tom Dayton at 06:40 AM on 10 May 2010Climate Change and the Integrity of Science: a letter to Science
Chris and Riccardo,may I gently suggest that you copy your comments about Spencer to a thread about sensitivity? Then perhaps our host can remove those comments from this thread and delete all subsequent comments by anybody on sensitivity from this thread? -
Marcel Bökstedt at 06:19 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
skepticstudent Please refrain from off topic comments, they clutter the thread. -
scepticmike at 05:57 AM on 10 May 2010Climate Change and the Integrity of Science: a letter to Science
Perhaps if you ignore "scepticstudent" he will go away. He seem to me to not adding anything useful to the discussion. -
chris at 05:54 AM on 10 May 2010Climate Change and the Integrity of Science: a letter to Science
johnd at 19:27 PM on 9 May, 2010 I suspect that Spencer's paper was allowed through once he removed any suggestion that his model and analysis has any particular relationship to the climate sensitivity as it is commonly understood (i.e. the change in the Earths equilibrium surface temperature in response to a radiative forcing equivalent to a doubling of atmospheric [CO2]). So for example Spencer and Braswell have qualified their description to point out that their analysis doesn't necessarily have much to say about climate sensitivity [***]. Particularly in the physical sciences, papers can be published that pursue a particular analysis in line with simplified physical models, even if these don't have any necessary relationship to the real world. I think this is one of these. No doubt it will take its chances and sink or swim according to its ultimate usefullness/validity (which on past experience is likely to be low). Of course we can be sure it will be trumpeted all over the blogosphere as (another!) "proof" that science has got it all wrong on atmospheric physics, the greenhouse effect and climate change. Plus ca change... ----------------------------------- [***]e.g. Spencer and Braswell conclude:"Although these feedback parameter estimates are all similar in magnitude, even if they do represent feedback operating on intraseasonal to interannual time scales it is not obvious how they relate to long-term climate sensitivity." and "Since feedback is traditionally referenced to surface temperature, extra caution must therefore be taken in the physical interpretation of any regression relationships that TOA radiative fluxes have to surface temperature variations."
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skepticstudent at 05:47 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
GFW I'm really trying to wrap my mind how you can say that water vapor and methane are "merely feedbacks" and CO2 is a "driver". It is well known I think on both sides, although I could be wrong, that CO2 is the 5th most powerful of the greenhouse gases in the greenhouse affect. so how could co2 be a "driver" and the others which are far more powerful be mere feedback. When the water rumbles and moves with the tide, it is the water vapor that comes out of the heating of the ocean that causes the hiccup of released co2. It's not co2 overpowering the water molecules to rise out of the ocean and force them to release the co2 into the atmospere. That is roughly similar to saying that the foot on the gas pedal is the driver and the person controlling the foot is merely along for the drive. -
skepticstudent at 05:37 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
In regards to Johns comments, when Paleo-ecologists don't even like to deal with numbers less than a million years without a shiver, how can someone write a paper about sensitivity over such a short time spand. That is similar to the hockey stick only going back to 1864. -
skepticstudent at 05:23 AM on 10 May 2010Climate Change and the Integrity of Science: a letter to Science
Toby, i think my ability to come in here and face the other side is proof that I am not faint of heart. Naomi Oreskes of the famed paper that says supposedly there are no scientific peer reviewed journals disputing ACGW. I would like to ask you how you can still quote the Mann paper as a viable piece of science when Mann gave M&M his information of his own volition from his ftp server. He forgot to remove the "classified" section which he talked about in the infamous hacked e-mails. With the FORTRAN program removed and the Graybill/Idso data removed which they said should NEVER be used for such purposes which right there makes it bad science. Then they ran over 10000 tests without the FORTRAN program and without the Greybill/Idso information and not once did they receive a hockey stick like effect. They put the FORTRAN and the Grebill/Idso back in and ran 9000 different runs with various data inputs, including lottery ticket numbers and phone numbers and they got consistent hockey stick effects. Mann made numerous comments in his “classified” file about not being able to get the hockey stick effect without the Greybill/Idso information from that group of trees. He chose to use information that was widely known not to be used for information science on temperature issues because these trees were an anomaly. If you wish to continue to state that such work as a fantastic piece of ACGW work that is your choice, however it is my choice to look at the information at hand and state categorically that it is not only bad for science but bad for educations.! Phil Jones and Michael Mann but discussed what a travesty it was that there was no way of making the Medieval warming period, and the little ice age disappear. When Mann put his paper out, he made them disappear and make it appear that there was a consistently smooth timeline of co2 and temperature until evil man started putting out that extra co2. And I would daresay that unless there was a typo that I missed it looked like John was agreeing with my point of view about tree regrowth being in unexpectedly large numbers in regards to larger amounts of co2. In fact at the end of his comments he said. It is indeed because of large amounts of carbon that the trees are having a faster than expected regrowth. I have not seen one good piece of empirical evidence that the M&M paper was incorrect. Mann has tried to say initially that they picked the wrong information. Then he sent them the link directly to his ftp server and said here use this information. He forgot to remove that infamous “classified” folder and has ever since tried to discredit McIntyre and Mckitrick not their science. And the comment you made about Oreskes saying there are multiple cross-threads of study showing that the globe is warming but the skeptics continue to ignore it is a total Non-Sequiter Skeptics including myself say and have said ad-nauseum, that skeptics deny that it is either anthropogenic, catastrophic, global or overall warming in nature. -
JMurphy at 05:11 AM on 10 May 2010Kung-fu Climate
OK, Poptech has previous history in regurgitating the same old arguments, thereby hijacking and spamming Comment sections. Please don't let him do the same here, if only for his own sake. See GREENFYRE : In fact Poptart [POPTECH] is so consistent at ignoring the substantive criticisms and mindlessly reiterating that the list is valid just because he says so that I really think he should rename it “Superfreakopeer-reviewed…” You will see all the same responses that he is posting here, but also a new one where he tells Harold Brooks that his paper is skeptical too and will remain in his list, even though Harold shows him how it can't possibly be what Poptech thinks it is. Poptech knows best, though, as usual. I think I can label you with the Dunning-Kruger effect without fear of any accusations from anyone...but yourself, of course - but that will only be the effect in action for all to see. -
Dikran Marsupial at 04:45 AM on 10 May 2010Kung-fu Climate
Poptech @ 246 "speak for yourself" So you would claim that you have the competence to understand all of the papers on your list? ad-hominem: A phrase applied to an argument or appeal founded on the preferences or principles of a particular person rather than on abstract truth or logical cogency. An ad-hominem is an attack on the source of an argument in place of ("rather than") an attack on the content of the argument. The criticism has been of the papers in your list, and hence is not an ad-hominem. The comments regarding the D-K effect have been prompted by the manner in which you have chosen to conduct the discussion. Suffering from D-K syndrome doesn't mean that your arguments are incorrect, and nobody has dismissed your list or your arguments on the basis of your manner. Hence no ad-hominem, just some criticism of your modus operandi that you would do well to take on board. -
Philippe Chantreau at 04:41 AM on 10 May 2010Kung-fu Climate
I'm rereading my post but can't find where I said you were experiencing D-K effect. I explained it and outlined the difference with an ad-hominem argument. I also defined what an ad-hom is. Furthermore, stating that someone is incompetent in an area would still not constitute an ad-hominem attack, especially if that incompetence is indeed a fact. Although I have over 3000 hrs of flight including 1500 as a flight instructor, I am not competent in aeronautical engineering. You can state that fact if you want. It does not constitute an adhom but certainly poses constraints on any argument I would formulate on aeronautical engineering, although I am more apt than the general population to discuss it. If I were to talk about it, I would remain safe from D-K effect by acknowledgeing my limitations and formulating my argument with the appropriate precautions. Do you have credentials to demonstrate you are competent in climate science (degrees, publications)? This will be my last comment about the Bond events, which indeed belong to another thread. It is unclear whether the Singer/Avery piece is peer-reviewed. It certainly is not a research paper and does not seem to add anything to the existing knowledge on the subject of Bond Events. Although Gerald Bond argues that these are the "continuation" of D.O events, their effect on climate is far from clear, unlike DO events. Only 1 Bond event left a temperature signature in the Greenland Ice. Some events correlate with glacier advances in the Eastern North-Atlantic region, or aridification of other regions. No Bond event correlate with a clear global climate signal. The scientific litterature is mentioned on the other thread. The true periodicity of the events is not established. Their duration is unclear. They could not explain both the MWP and LIA. I am quite skeptical that they can explain anything about the 20th century climate trend. -
GFW at 04:25 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
HumanityRules, to understand why CO2 is the driver, all you really need is to understand why the other things mentioned (water vapor, snow albedo, ice albedo, ...) are feedbacks, not drivers. Water vapor is a feedback because we have vast amounts of liquid water that can evaporate if it gets warmer and rain will fall any time there's too much water vapor. Similarly, warmer temps melt snow & ice earlier in the year while colder temps preserve them ... feedback. So feedbacks are things that have a natural mechanism for increasing and decreasing on similar timescales. A driver (aka a forcing) has to be something that is either entirely external (e.g. the sun) or is something that changes in an asymmetric manner (where the extreme example is humans burning fossil fuels in a couple of centuries that took millions of years to be laid down). Volcanoes produce aerosols (short term negative forcing) and CO2 (long term positive forcing). Methane can be a forcing, although not as long-lived as CO2. Man-made land-use changes (e.g. clearing forest for cropland) are a forcing if maintained. Vegetation change in response to climate change is a (slow) feedback. Does that help? -
Estimating climate sensitivity from 3 million years ago
HumanityRules, From the abstract: Here we use a coupled atmosphere–ocean general circulation model to simulate the climate of the mid-Pliocene warm period (about three million years ago), and analyse the forcings and feedbacks that contributed to the relatively warm temperatures. Furthermore, we compare our simulation with proxy records of mid-Pliocene sea surface temperature. Since the authors are using a climate model, they should be able to directly analyze which forcings and feedbacks contribute to the warming. -
Dikran Marsupial at 03:56 AM on 10 May 2010Kung-fu Climate
Poptech @ 243 "Accusing someone of having the D-K effect is accusing someone of being incompetent and thus an ad hominem attack. If you are accusing me of the D-K effect then you are trying to creatively call me incompetent." Yes, you are incompetent, as am I, as are most of the contributors to climate blogs. Very few of us are active climatologists, oceanographers, ecologists etc. Even amongst the top climate scientists very few have sufficient expertise to claim competence in all of the topics covered in your list of papers, so it would be extremely impressive (read extremly unlikely) if you were genuinely competent in all those areas. The difference is we have a much better idea of the limits of our competence. You shouldn't take that as an insult or an ad-hominem. It isn't, it is just some well-meant advice that was not heeded when given less directly. If you want to do the skeptic camp a favour, or convince people you are right, then a change of approach is in order. -
Marcel Bökstedt at 03:43 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
Profmandia> I think that the weathering processes are one of the main subjects of study in the paper by Lunt et al. The way I understand it, they try to reconstruct weathering(orography), vegetation, ice sheets, CO2 and temperature at a particular time. They assume that all these data describe an equilibrium state for the climate. Then they check what values of Earth system sensitivity is compatible with this assembly of data. This last step presumably involves some choices of models. I can't even venture a guess about how accurate this method is, but it certainly takes the rocks into account. tobyjoyce> Me too. I can't make sense of what Dr. Spencer writes either. I think it's best to wait for a fuller account before trying again. HumanityRules> I think that your remark is that the world of mid-pliocene (-3.29 to -2.97 million years) was so different from the present world that we can't use present day models to describe the climate of that time. That is certainly an important objection, and I'm not sure how certain Lunt et al. are about the models they have to use to connect the dots, but they certainly do discuss ancient geography and flora. To be more specific, I believe that the Panama Isthmus was alread formed at this time, and the mountain ranges you mentioned were not that drastically different from today. But I don't know for sure...:) -
Tom Dayton at 03:41 AM on 10 May 2010Kung-fu Climate
Poptech, Singer's contention that you linked to is indeed the specific topic of the SkepticalScience post It's Just a Natural Cycle. That's where further discussion of it belongs. -
Tom Dayton at 03:31 AM on 10 May 2010Kung-fu Climate
I think the 1500 year climate cycle theory that some people have brought up are the Dansgaard-Oeschger events, which are discussed in the post It’s just a natural cycle. -
michael sweet at 03:23 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
Dr Hansen has estimated a total climate sensitivity of 6C. hansen abstract 6C. Some people consider him to be an alarmist, but I think he has a long record of having been correct. By contrast, Spenser has often been wrong. His satalite data was affected by orbit decay and he insisted it was correct for a long time before he was forced to correct it. -
Philippe Chantreau at 03:22 AM on 10 May 2010Kung-fu Climate
The 1500 climate cycle theory? What exactly does it consist of? Are we supposed to be experiencing such a cycle right now that would explain the late 20th century's temps? A bit of clarification: a reference to D-K effect is not an ad-hominem attack. An ad-hominem attack would consist of saying that so and so is a bad person because of some reason (i.e. they don't like puppies), then proceeding on to argue that it makes such and such argument from that person wrong, regardless of the validity of the argument itself. The D-K effect refers to the attitude consisting of believing that a little knowledge makes one qualified enough to discuss what pertains to advanced expertise. It is not a personal attack to state that one does not possess advanced expertise of a subject. It does relate to the validity of their argument if that argument pertains to the subject in which they overestimate their expertise. -
JMurphy at 03:13 AM on 10 May 2010Kung-fu Climate
Back to that list, we have : An Alternative View of Climate Change for Steelmakers (PDF) (Iron & Steel Technology, Volume 5, Number 7, pp. 87-98, July 2008) - John Stubbles On his site, Poptech uses this quote from the journal : "readers will find timely peer-reviewed articles", just to show that it is actually peer-reviewed. Unfortunately, he left off this bit : "...addressing theory, technology and practical applications..." The paper Poptech is referring to is in no way a peer-reviewed article as determined by the journal's own criteria (as you can see for yourself from a list of the contents of that edition), and its only source (apart from the journal itself) is from a blog called SPYDERCAT, although you can't actually access it from the home page of SPYDERCAT, for some reason. It was written by the late Dr. John Stubbles, a Steel Industry Consultant, and the second line starts thus : The “alarmists,” spearheaded by Al Gore... It uses proxies from a study on the Sargasso Sea from 1996 to claim a globally warmer MWP than now; uses a blog posting by John Daly to claim that Mann's hockey-stick is broken, and includes references from Watts (yes, the weatherman), Pat Michaels, Soon, Christy, the Idsos, Singer and Morner. In fact, it is all the so-called skeptical arguments in one package. Read it for a laugh and then think on Poptech's rationale for including such an article. -
Tom Dayton at 03:08 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
tobyjoyce, I think that the fundamental flaw in Spencer's approach is the same in his new article as it has been in the past: He's analyzing changes across such short time spans (one month in this case) that the short time across those analyzed months (7 years in this case) inherently is incapable of detecting the slower-than-hummingbird-wingbeats feedbacks that provide the large sensitivity that are the threat. I think that is the same flawed approach that Tamino debunked in his post Spencer's Folly 3. (For the least technical explanation, search down that page for "You may also notice" and read down from there.) But I'm unsure, so I've asked Tamino. I've also asked Chris Colose to please give a less technical explanation. -
Rob Honeycutt at 02:57 AM on 10 May 2010Climate Change and the Integrity of Science: a letter to Science
A very short question for skepticalstudent... Of all the arguments you've put forth, do you think you've presented anything that the 255 NAS letter signatories have not carefully considered? I would note again that these are the supposed to be the 255 NAS members who are most familiar with climate science. -
Rob Honeycutt at 02:53 AM on 10 May 2010Kung-fu Climate
Poptech said... "The substantial statements have already been provided above. This work has already been done." Actually, no, it hasn't. For one, the Oregon Petition is not audited by any independent group. There are many who have requested to have their names removed and those requests have been ignored. There are a large number of fictitious names on the list. Come on, dude! One up these people! Step up to the plate and do something substantive, verifiable and crushing to your detractors. Lest you think it's not possible or are unwilling to put in the effort... -
tobyjoyce at 02:38 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
Dr. Roy Spencer is (we hear) about to publish a paper (accepted for publication) which estimates a much lower value for climate sensitivity than used in IPCC reports. he has an advanced taste at his blog, but dammed if I can make sense of it. BTW, that is probably me. Dr. Roy Spencer Anyone care to read his post and comment? -
Stephen Baines at 02:18 AM on 10 May 2010Climate Change and the Integrity of Science: a letter to Science
Sorry about the double post everybody. The screen hung after submitting my first reply. johnd at 155. I reread my post and you'll have to enlighten me further. How is the system that I described -- where you acn't review papers of those with whom you have conflict of interest, and which fosters intense competition that ensures you will face critical opinions -- likely to produce an old boys network. I don't see it. -
HumanityRules at 02:16 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
5.ProfMandia Thanks for that. I don't doubt CO2 is released I'm just asking why is this released CO2 the primer for all the other processes that occured which lead to the warm climate. Here's a short list of the things that were occuring in this period. The Himalayan Mountains formed. In America, the Cascades, Rockies, Appalachians, and the Colorado plateaus were uplifted, and there was activity in the mountains of Alaska and in the Great Basin ranges of Nevada and Utah. The end of the Pliocene was marked in North America by the Cascadian revolution, during which the Sierra Nevada was elevated and tilted to the west. In Europe as well many mountain ranges built up, including the Alps, which were folded and thrusted. The Isthmus of Panama formed cutting off the Atlantic, completely altering ocean circulation and allowing conditions for greater ice accumulation at the poles. Why can't the formation of these mountains in and of themselves alter weather patterns, change the hydrological cycle, cause savannahization and desertification, alter vegation patterns, change wind and circulation patterns, change precipitation to snow rather than rain, allow the beginning of glaciation and change aerosol and dust levels all independantly of how much CO2 is released by tectonics. Why are the other factors a result of extra CO2 in the atmosphere and not mountain building and isthamus formation. (A large section of this was pasted from http://www.ucmp.berkeley.edu/tertiary/pli/plitect.html) -
Dikran Marsupial at 02:06 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
Cheer's Scott, I'm happy to stand corrected. I'll have to go to Roy's blog and see where he gets the numbers from. -
JMurphy at 01:58 AM on 10 May 2010Kung-fu Climate
"However, my analysis of a long-term data set of hurricane losses in the United States shows no upward trend once the data are normalized to remove the effects of societal changes." Poptech asserts, using the above Pielke quote : "This supports skeptical arguments against alarmist claims of Hurricane damage is getting worse due to global warming or "economic effects of"." How do the effects of hurricanes on America support any argument against global warming ? Do you think America represents the world ? Please provide the 'alarmist claims' you think this Pielke paper skeptically argues against. -
ProfMandia at 01:57 AM on 10 May 2010Estimating climate sensitivity from 3 million years ago
HumanityRules: The figure below (Ruddiman, 2008) shows how carbon is cycled into and out of the atmosphere by plate tectonics over millions of years.
Through a process known as chemical weathering, rainwater combines with CO2 gas in the air and forms carbonic acid. Carbonic acid "attacks" the silicate bedrock and creates carbon-containing ions that are carried to the ocean by rivers. This carbon is ultimately stored in the shells of marine plankton. When marine plankton die, they fall to the sea floor where their carbon gets buried in the sediment. Therefore, chemical weathering removes atmospheric carbon and causes a cooler climate.
During the process of plate tectonics the sea floor spreads. As the sea floor spreads, sediment containing carbon is forced into the earth's interior (by a process known as subduction) and is melted. When magma rises and is ejected by volcanoes, the carbon is released back into the air. During increased periods of plate tectonics (more volcanism) there are higher levels of CO2 in the atmosphere and the climate warms.
Approximately 55 million years ago, India slammed into Asia and began to build the Himalayan Mountains. These mountains are still rising today. Due to the massive amount of material being uplifted by this collision, chemical weathering rates over the past 55 million years have been very high resulting in a gradual tectonic cooling since that time.
Scott A. Mandia, Professor of Physical Sciences
Selden, NY
Global Warming: Man or Myth?
My Global Warming Blog
Twitter: AGW_Prof
"Global Warming Fact of the Day" Facebook Group
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Dikran Marsupial at 01:56 AM on 10 May 2010Kung-fu Climate
Poptech @ 234 You do know, don't you that Lassen later published a paper updating the results in Friss-Christensen and Lassen, and found that the correlation had indeed broken down, see here for details. So one of the authors of the paper disagrees with you (plus ca change). Also, I suspect that the refutation wasn't published in the peer-reviewed literature. As I said, clinging onto to papers that have been refuted (including by one of the authors) is damaging to the skeptic cause, but go for it if it pleases you. You just can't help some people.
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