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Riccardo at 19:23 PM on 23 May 2010It's the sun
Friend, the microwave power emitted by the sun is many orders of magnitude lower the the IR or visible emission. I'd not expect any significant effect. -
Riccardo at 19:19 PM on 23 May 2010Arctic sea ice has recovered
Erik, fig. 2 above is not a forecast but a model calculation of ice volume, where the measured relevant parameters are fed in. Section 2 of the paper describes the model, the first paragraph of section 3 describe how they use it in forecast mode. -
Si at 18:55 PM on 23 May 2010There is no consensus
Doug, it is a plea for more funding. "It calls for a new era of climate change science where an emphasis is placed on "fundamental, use-inspired" research," -
tobyjoyce at 17:57 PM on 23 May 2010Robust warming of the global upper ocean
P.s. The link to Lyman(2010) needs to be fixed!Response: Fixed, thanks for pointing that out. -
tobyjoyce at 17:55 PM on 23 May 2010Robust warming of the global upper ocean
I would like just to check the meaning of the word "robust" in this context. In statistics, a "robust estimate" is one that is not affected by small departures from model assumptions. Does the phrase "robust warming trend" have the same meaning here? -
mike at 17:51 PM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
63 johnd at 08:34 AM on 22 May, 2010 "Whether taking simple surface sediment cores or cores from deep below in the search for natural resources, there is a strict regime on what is required to satisfy firstly those who will decide whether to proceed further or not, and an even tighter requirement for it to become part of a bankable feasibility study, and then even tighter beyond that." johnd- As a research geologist with some small amount of experience in mineral exploration, I think your criticisms are off base. In the world of publicly-funded science, "those who will decide whether to proceed further or not" and for work to "become part of a bankable feasibility study" are the peer reviewers of the journal where the work is published. The fact that Dr Tierney's paper appears in Nature Geoscience - a very prestigious journal with a low acceptance rate - means that your quality-control concerns would have been met more than adequately in the review process. Your continued questioning in this regard is as inappropriate as would mine be of your professional work. The difference of course is that your proprietary output is protected from comment by the ignorant whereas the work of those who publish in the peer-reviewed literature is available to all to pick over. -
Phila at 17:25 PM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
#120 Frogstar "As a (skeptical) scientist, I am here because the topics under discussion are being used in a semi-technical geopolitical debate that involves subjects very dear to my heart (life, death, money, taxes, etc)." The policy implications are well worth discussing and there's plenty of room for honest disagreement. It's a serious subject, and ideally, we'd all be having an serious conversation about it. Unfortunately, that discussion is largely being postponed so that we can argue over whether CO2 is actually a greenhouse gas, whether Jessica Tierney actually knows how to conduct research, or what have you. "The kinetics in that lab taught me a lot about waiting to see if measurements bore out predictions and, when they didn't, it was a learning opportunity." That's a reasonable approach in many situations. This situation is a bit trickier, obviously, because the prognosis gets worse as we wait and there are no do-overs, as far as we know. The better analogy here would be to medicine: With some conditions, you can wait for measurements to bear out predictions. With others, doing so would be...well, let's just say "unwise." -
Doug Bostrom at 16:40 PM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
Presumably frogster is referring to such serious and enlightening remarks from so-called skeptics as: One tree does not a hockey stick make ;-) or LOL. Has anyone happened to notice that this study is basically about fishing for sardines? Regarding speaking to truckers, frogster, I think it would not be too difficult to show how Willis' critique of Tierney's paper is not aimed at the side of the correct barn. "Your oil pressure gauge is wrong, you know that it reads 50psi when it really is measuring 60psi. If the reading on the gauge drops to 40psi you know you've got a loss of oil pressure, even if you know the reading is 'wrong'." Not complicated. -
Albatross at 16:21 PM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
thefrogstar @120 "climate science thought it could 'run with the big boys' yet still go on 'providing weather forecasts'." There is so much wrong that statement-- I'm not sure whether your erroneous comparsion with weather forecasts was intentional or not. Anyhow, I'll leave it there. As for your claim about some of the points being raised by contrians here being "valid". I strongly disagree, and that is exactly why I and others are getting frustrated. Do you not see how arrogant and rude it is by some here to presume to know more than the people (e.g., Dr. Tierney and her colleagues) who have worked so hard on this, those who have researched the topic at hand (i.e., literature review), wrote the proposal, invested the time and effort to collect the data, processed it, analysed it, checked the numbers, written it up, gone through several iterations, and then finally gone through peer review (a very humbling and exhausting experience in most cases), only to have some people posting on an internet blog (who are not even qualified or experienced in the field and who have not taken the time and effort to understand the problem in the first place)cavalierly dismiss it as sardine research. And worse yet, doing so not using rational and informed scientific critique and methods, but essentially taking cheap shots. I sense no inclination whatsoever from certain contrarians to learn form this paper, or other climate papers, or to concede when they have been shown to be wrong. Does that not tell you something or concern you? Moreover, most of the criticisms raised here have been addressed by the authors, and people who have published on the subject prior to this study (this study does not stand in isolation, it is part of a much bigger picture of scientific understanding), yet the contrarians it seems could not be bothered to first do the leg work to determine whether or not their "concerns" had been addressed before making condescending remarks. This has happened repeatedly in recent years in the field of climate science and related disciplines, and to be candid, it is getting incredibly tiresome. I'll agree with you that the IPCC has done a relatively poor job at communicating the science. That said, they are, believe it or not, reliant on the volunteer work of hundreds of scientists and have very few full time staff. They do not have a well-oiled, experienced and politically savvy PR team. Anyhow, let us hope that they are provided the means required to communicate the science and the gravity of this situation in AR5. And frogstar, the hubris I am seeing (on an increasing scale) is coming from the contrarians and "skeptics". I am pretty highly qualified in my field, but I don't not presume to know more, or feel inclined to be contrary or question the science of an oncologist, for example. Additionally, I acccept that they are highly trained, experienced and professional, and that it would be incredibly arrogant and disrespectful (paranoid even?) of me to feel obligated to openly question their work simply because they were the bearer of bad news or news that their findings did not sit well with me. And, in the event I did elect to attack or question their research after Googling for a few days, I would not be offended (or surprised) if they set me straight, were rather snarky or accused me of hubris even if I do happen to have post graduate degree/s in another unrelated field. -
thefrogstar at 15:20 PM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
Phila #118, The science on these threads can, and will, progress, irrespective of whether skeptics arguments turn out to be correct or not. As a (skeptical) scientist, I am here because the topics under discussion are being used in a semi-technical geopolitical debate that involves subjects very dear to my heart (life, death, money, taxes, etc). That's inevitably going to bring more scrutiny, from people at all levels of scientific education and competence. Yes, it's uncomfortable. My adviser used to tell us (his research group) that if we "couldn't explain what we did, and why it was important, to a truck driver in a honky-tonk bar in Texas, and why they should be paying for it", then we should ask ourselves some serious questions. Frankly, what I read on this particular thread, is a bunch of people being quite rude and disparaging towards (a few) other people who are clearly scientifically competent and seem to be raising valid points. That approach is not going to get very far with the truck drivers. Without being (too) rude, I sometimes wonder if climate science thought it could 'run with the big boys' yet still go on 'providing weather forecasts'. Another thing my supervisor told us is "that we're a kinetics lab". The kinetics in that lab taught me a lot about waiting to see if measurements bore out predictions and, when they didn't, it was a learning opportunity. Unfortunately climate science doesn't work on the same time scale as most other sciences, and the hubris seems to be commensurately greater. -
Friend at 12:55 PM on 23 May 2010It's the sun
Isn't it possible that the Sun is causing an increase in temperature of the core of the earth by way of radiation that passes harmlessly through the atmosphere and crust much like a microwave oven? Or is this just impossible? thanks -
Doug Bostrom at 12:17 PM on 23 May 2010Climate's changed before
Roger, what's to discuss? The National Academy of Sciences says anthropogenic warming is a fact, you say it's not and you're quite unprepared to accept otherwise. I'm a bystander to your argument with the NAS but I have to say, I attach more weight to their conclusion and not yours. Are you surprised, that I'd have to give more credit to the NAS and their conclusion based on a veritable mountain of evidence, as opposed to your personal opinion supported by a Youtube video? What an extraordinary conversation. I've participated in many such yet they still leave my head spinning. Either one must leave the merry-go-round filled with folks who show every sign of technical psychosis or one must jump on and join the endless revolution of repetitions. -
Rogerthesurf at 11:50 AM on 23 May 2010Climate's changed before
Doug, Have done, However I expect you to use your brain to discuss my point. I dont give two hoots what the NAS says, unless they can show me how the "Anthropogenic CO2 causes Global Warming" hypothesis is proven. Now that would be not unreasonable to expect from a bunch of scientists right? And it might be news to you but "anthropogenic warming" is not considered to be fact, even in IPCC reports and there is an increasing body of opinion that support what I am questioning. But most importantly, lets not forget this conversation is about whether this blog addresses the question "What does past climate change tell us about global warming?" and I am maintaining that it skirts around the real issue which is what I am raising here. Cheers Roger -
Doug Bostrom at 11:30 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
You're of course entitled to your opinion that the paper under discussion here is "primarily about sardine production" when sardines are not mentioned in the title. I'm uncomfortably prepared to concede that the paper would possibly have been better focused if it had confined itself to paleotemperature reconstruction but technically speaking I don't have the background to say that. For my part-- concerned as I am with climate change-- the significance of the paper lies in what its title says. Probably needless to say, but the reason I found my way here was because of climate problems, not a shortage of sardines. At the end of the day, your argument still consists of "I doubt it." But there's no such thing as a last word in a venue such as this so I'm going to ignore what you have to say next about this unless you veer off in some other direction. -
Phila at 11:23 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
#101 "e and Phila, 94 and 95. I think there are rather more skeptical climate scientists than you realise. - Spencer, Michaels, Christy" Yes, there are some skeptical climate scientists out there, and they've been making their views known for years, as they should. I fail to see what this has to do with people who lack any relevant expertise casually accusing working scientists of not understanding their own fields. How does such behavior make science "more robust"? More to the point, how could science ever progress if it were obliged to cater to that odd combination of arrogance and ignorance? Look, I'd love to revolutionize evolutionary biology, or any other field...but realistically, what are the chances I'm going to do that without educating myself to at least the level of a grad student, not just in the subject itself but also in the nuts and bolts of scientific practice and discourse? The skeptical scientists you've named have so far failed to convince very many of their colleagues that they're right and everyone else is wrong. But they do have credentials and they've more or less followed the rules of the game. As such, their contributions are valuable even if they're incorrect. But too many amateur "skeptical" arguments -- including some of the ones on this thread -- fall under the category of "not even wrong." We agree that it's healthy to have people get more interested in and involved with science. But we seem to disagree about the amount of time, effort, and humility it takes to get good at it. As I see it, no one deserves an 'A' just for showing up. -
johnd at 11:19 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
michael sweet at 10:47 AM, it would be appreciated if you would stop assigning your own meanings to my posts which you tend to twist into a supposed insult against someone else. It is not what reflects on me that should concern you. If I'm not mistaken, one of the studies I referred to earlier on a couple of occasions was part of the Nyanza Project, there are numerous such papers available. Variability was a matter that seemed to pop up quite frequently which is what the focus of my posts have been on, and whether or not is has been accommodated or allowed for. -
Doug Bostrom at 11:12 AM on 23 May 2010Climate's changed before
Roger, you should add this to your blog because it speaks to the weight of your opinion on this subject: Some scientific conclusions or theories have been so thoroughly examined and tested, and supported by so many independent observations and results, that their likelihood of subsequently being found to be wrong is vanishingly small. Such conclusions and theories are then regarded as settled facts. This is the case for the conclusions that the Earth system is warming and that much of this warming is very likely due to human activities. That's from the National Academy of Sciences. You can find the press release for this just-released report as well as links to the report itself here. What is this "National Academy of Sciences"? You can learn about it here. It's sort of like the UK's Royal Society but with the brand of USA on it. The basic point is, anthropogenic warming is considered to be fact, uncontroversially so in terms of scientific understanding. If you dig into the science you'll find past changes of climate playing the role of evidence in support of this fact. -
johnd at 11:04 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
doug_bostrom at 10:19 AM, apparently it is not only me that you consider to suffer from cognitive disconnect. In case you haven't read to the end of the article abstract as yet, or the lead at the top of this thread. Here is the last sentence from the abstract which I think I already had referred you to earlier. "We conclude that these unprecedented temperatures and a corresponding decrease in productivity can be attributed to anthropogenic global warming, with potentially important implications for the Lake Tanganyika fishery." Note that the word productivity is mentioned repeatedly. It measured evidence of historic productivity. It attempted to correlate recent temperatures with recent productivity. Finally it reached conclusions about future fishery productivity, of which sardines are the primary catch. In addition, carefully read the post which leads this thread and look at the only two questions John posed. I imagine they were asked as part of initiating the direction of the topic for discussion. "What effect does temperature have on the lake's sardine population?" "How does temperature affect primary productivity?" -
Eric (skeptic) at 11:00 AM on 23 May 2010Arctic sea ice has recovered
The volume chart above relies on the PIOMAS model. The model seems fine for predicting the summer minimum near the beginning of the melt season. See for example, the predictions for 2008: http://psc.apl.washington.edu/IDAO/seasonal_outlook.html Here they made an essentially correct prediction of substantially higher ice in Sept 2008 than Sept 2007. During the previous winter (2007-2008) they wrote a paper predicting the 2008 summer ice extent: LINK In this paper they predicted less ice than 2007 (a new record low) provided that weather forcings (not part of their model) remained substantially similar to 2007. Apparently they did not because the prediction was wrong. Unfortunately I have yet to find a followup paper explaining why the prediction was wrong. The paper emphasizes the use of thickness in the model as a major part of the prediction of extent. But if the thickness is wrong, then the predicted extent would also be wrong. Likewise, if the thickness is wrong in hindcasts when thickness was not measured extensively, then hindcasts of volume would also be invalid. I believe that caveat belongs on fig 2 above.
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michael sweet at 10:47 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
Johnd, Perhaps if you read some of the references that Chris gives you you will be less confused. In post 50, he refers to the Nyanza Project. This paper was written as part of that project. One of the lead scientists is a FISHERIES expert. I expect that Dr. Teirney discussed overfishing with them at some time during the month she was in Africa, and considered that information when she wrote this paper. Several other scientists are lake productivity specialists. These people spend their lives doing this work. Your insinuation that they are stupid and uninformed, because you have not bothered to read the background information is unconvincing. This paper is part of a large series of papers which document the lake. Your claim that they neglected some important facts because they wrote a different paper you have not read reflects only on you. -
Rogerthesurf at 10:38 AM on 23 May 2010Climate's changed before
Response, Your reply is faithfully included in my blog. I am not disputing any of the findings that you mention in your answer, although some might, but none of this information proves in any way that anthropogenic CO2 is the root cause. My argument which is simply based on the standard scientific proof of a hypothesis, is not hard to understand, but for your benefit I will explain more. Even in the absence of previous warmings, the earth could be heating up for some other reason. The fact that there are well documented and general agreement that there have been previous warmings, such as the Holocene Maximum, the Minoan Warming, the Roman warming and the Medieval Warm Period, which are recorded in history as well as scientific proxies and the like, make CO2 as the root cause of global warming even less likely. The situation can be likened to the problem that pharmaceutical researchers have. If a patient is ill and you give him some of your new drug, and the patient gets well:- Did he get well because of the drug, or did he get well anyway? Very hard to tell, so as you should be aware, this problem is solved by doing double blind tests on a large sample of patients and doing a statistical analysis of the results. (Double blind because if the patient knows if he is receiving the drug or placebo, it effects his response, as the response is also effected if the person administering knows whether it is the drug or a placebo) To further illustrate the difficulty of proving a hypothesis, I recommend watching the following video. http://www.youtube.com/watch?v=TxiBHNeTG7o&feature=related The video has nothing to do with CO2 or global warming, but illustrates well the problems of hypothesis proof. A number of people died when the captain of this aircraft formed a hypothesis of what was wrong with the plane, an incident seemed to support his hypothesis, but in spite of definitive disproof of his hypothesis being readily available, because the hypothesis was incorrect, the aircraft crashed. In fact there are a number of known things which could cause the current warming, and probably a greater number of factors which are unknown. I hope this clarifies things for you and your readers. Please take the time to watch the video. This response is also posted on http://www.globalwarmingsupporter.wordpress.com Cheers RogerResponse: "The fact that there are well documented and general agreement that there have been previous warmings... make CO2 as the root cause of global warming even less likely"
The degree and global extent of warming is still debated for certain periods (re the Medieval Warm Period) but putting that aside, we can all agree that there have been many periods in Earth's history when the planet has experienced dramatic changes in temperature.
Why has climate changed in the past? The primary driver of Earth's climate is and has always been changes in the planet's energy imbalance. If anything causes a change in the energy coming in or going out, that will lead to warming or cooling. This can include the sun getting hotter, more aerosols in the air reflecting incoming sunlight, more CO2 absorbing infrared radiation, etc. CO2 is not the only driver of climate - in the past, various factors have driven Earth's climate. The one constant is that an energy imbalance has driven temperature change.
So what does past climate change tell us? It tells us that when the planet suffers an energy imbalance, global temperature changes. It doesn't mean CO2 is always the main driver of past climate change. The ice age cycles of the past million years were driven initially by orbital cycles, not CO2 (but CO2 does play a positive feedback role).
A crucial piece of information we learn from past history is how much climate responds to an energy imbalance. How sensitive is our climate? And what we find is when our planet accumulates heat, there is a net positive feedback response from our climate which amplifies the initial warming. Past climate change reveals a key truth: our climate is sensitive. If you impose an energy imbalance on our planet, positive feedbacks will amplify the initial warming.
What does this have to do with CO2? We know rising CO2 is causing an energy imbalance because of direct observations (satellites observing less infrared radiation escaping to space and surface measurements of more downward infrared radiation).
So we have two pieces of information from empirical data:
1. Direct measurements today find CO2 is imposing an energy imbalance
2. Past climate change finds the climate is sensitive to an energy imbalance
Our understanding of climate comes from considering the full body of evidence. You need to consider past climate change in the context of the current energy imbalance imposed by CO2. -
Doug Bostrom at 10:19 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
Here's a nice example of cognitive disconnect: My comment about checking the local temperature was having a shot at those who had gone off on a tangent drawing all manner of conclusions about AGW when the study was primarily about sardine production. Title of article under discussion as it appears in Nature: Late-twentieth-century warming in Lake Tanganyika unprecedented since AD 500 I'm sorry johnd but I find you unreasonable in the technical sense of the term. -
Doug Bostrom at 10:09 AM on 23 May 2010There is no consensus
Against the Chicago rally of policy think tanks, industrial interests and latter-day Don Quixote researchers bereft of a Panza to look after their linens, let's stack the National Academies of Science and their unit the National Research Council. NAS has just released a rather stunning compendium of climate research findings, mitigation options and adaptation possibilities. Here's the takeaway for us laypersons, from the climate research portion of the set: Some scientific conclusions or theories have been so thoroughly examined and tested, and supported by so many independent observations and results, that their likelihood of subsequently being found to be wrong is vanishingly small. Such conclusions and theories are then regarded as settled facts. This is the case for the conclusions that the Earth system is warming and that much of this warming is very likely due to human activities. You can find the press summary of the reports here. A free-to-read version of the report is here Now I'm sure that we'll hear squawks from people entirely clueless about what the National Academies represents to the effect that the NAS is simply ensuring that grant money continue flowing but consider, if their conclusion is that anthropogenic climate change is a settled fact beyond dispute, that hardly serves as an incentive to pouring more money into research, does it? In any case such an argument is worthless in terms of offering an alternative to accepted research findings. -
johnd at 10:07 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
doug_bostrom at 08:24 AM, and e at 08:45 AM, the key point being missed is that the variations of layers of BSi deposited on the lake bottom was interpreted as variations of the lake productivity, in the scope of the study, further translated into sardine production. Using one core sample, which doesn't seem to allow for the reports on how variable the sardine productivity is over the 700km long lake, nor how the lake surface temperature varies, the study was able to find some correlation of the inferred variations in productivity with ALREADY reconstructed GLOBAL temperatures over the same time frame. The supposed proof of the relationship is that sardines catches have fallen in recent decades whilst lake surface temperatures had risen as recorded by instruments over the last 90 years. The problem I see is that for the connection to be validated the rate of BSi deposition over the last 90 years has to correlated with the lake surface temperatures that have been recorded, and that is where this study is weak. Firstly, the relevant top of one core was unable to be used, and the bottom of the other one was not used for some unspecified reason, so there is only assumed continuity. Secondly other studies, one which I provided the link for in an earlier post, collected samples in a more controlled manner taking surface samples along a designated transect in two different locations and found variations of BSi in the order of 0.01-1.07% and 0.1-2.9% at an assumed sedimentation rate of 1mm/year. The Teirney study determined a sedimentation rate of 0.5mm/year which was used to model age for the top 100mm, and their analyse yielded a BSi content varying from 10-60%. The BSi difference may be due to different lab procedures, but as can be seen the Tierny % varies by a factor of 6 whereas in the other study by factors of up to 100 or even closer to 300 across the two, hence their noting of the high variability and the need to recognise this if paleoclimate studies are to be conducted in the lake.. Thirdly, overfishing appears as not to have been considered a possibility, whereas elsewhere in the world declining fish numbers are blamed on that. My comment about checking the local temperature was having a shot at those who had gone off on a tangent drawing all manner of conclusions about AGW when the study was primarily about sardine production. -
Albatross at 09:26 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
e @115, Don't forget Menne et al. (2010). -
Unprecedented Warming in Lake Tanganyika and its impact on humanity
Si >"doug you need good data. One tree does not a hockey stick make ;-)" You are misunderstanding Willis's argument. It's not that the reconstruction is "bad" per se, but that it hasn't been calibrated to surface temperatures. This suggests that the record may be off from absolute correct temperatures by a certain factor. That factor would remain constant however, so the overall shape of the trend (which is what we are interested in) would not be affected. This is the point that doug is making. >"You are going to have to wait for Anthony's surface station report but it is coming!" Thanks, we know. He's been promising it for a long time now. Ask yourself this: why does Watts spend so much time documenting "bad" weather stations, but never bothers to plot the temperature records of "bad" stations vs. "good" stations? It's a rather trivial thing to do. In any case, we don't have to wait for his report, others have done the work for him. You can read about the results here, and John's posts here and here. As it is off topic from this post, please post any followups to the weather station discussion to one of those two posts. -
Albatross at 08:55 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
From Tierney et al's web page: "What about Geothermal heating? Isn’t Tanganyika in a rift zone? Could that be responsible for the warming? Lake Tanganyika is indeed part of the East African rift system. But there is no evidence for increased deepwater volcanic activity in the lake in the 20th century. In 1971, a survey team found that the rate of geothermal heat flux in Tanganyika was 0.04 watts per meters squared, close to the global average (Degens et al., 1971, Naturwissenschaften). That’s 10-fold less than the estimated heat absorption of the lake since 1913 thought due to global warming (0.4 watts per meters squared; Verburg and Hecky, 2009, Limnology & Oceanography). What is more, were there increased volcanism we would detect a change in the water chemistry of the lake (which has not been observed), plus we would see a thermal “inversion” - warmer waters in the depths of the lake. In fact, as you can see below from an inset graph from our Nature Geoscience paper, the deep portion of the lake (hypolimnion) is cooler than the surface and middle-portion of the lake (110 meters depth) and the deep waters are warming more slowly than the surface waters. This is consistent with a heating source from above - not below - the lake." -
Albatross at 08:53 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
Si, SS and johnd, How many Vostok ice cores were made? And I am not talking about individual core samples. How about EPICA? At how many locations did they drill cores for those projects? Regarding the red herring of hydrothermal actvity. Authors addressed that see #79. Also, have you thought for a minute that those vents have probably been present for millenia, and that they are on the lake bottom and the authors are talkiing about warming of LST. That is akin to Monckton claiming that El Ninos are caused by undersea volcanoes, or thinking that that undersea volcanoes explain the increase in 0-2000 m glbal OHC. If the lake was being warmed from below, the lower depths would have locally been warming at a rate much higher than has been observed and the LSTs would not be consistent with the surrounding SATs, which they are. These data have clearly not been contaminated by hydrothermal activity. Really guys, you are grasping at straws and it is all too painfully apparant. SS says s/he has spent a few days looking at this on the internet. Wow, really? Scientists have devoted careers and students 5-6 years of their PhDs studying this issue and thereby reading hundreds, if not thousands, of papers. Not to mention that this paper was reviewed and critiqued by their peers, who are experts in the field. The contrarians do not like the findings because they are yet more evidence that AGW is an issue and add to an already coherent and cohesive picture. So the best they can do is to try and make some rather lame attempts undermine the scientists' credibility. Johnd @100, "LOL. Has anyone happened to notice that this study is basically about fishing for sardines?" Please gorow up and show some respect. If you have not noticed the obvious, we have not had thermometers around for anywhere close to 1500 years, nevermind isolated equatorial regions in Africa. Tierney is probably reading some of the contrarian comments on this read and shaking her head in disbelief, and who can blame her. And for those willing to accept Eschenbach's "critique" of the Tierney et al. paper at face value, I would caution you against doing so. Willis has a reputation for, how shall I say this, for playing loose with the facts as has been shown several times by Dr. Lambert and others. That and the fact that he is not an expert in this field. EOS. -
Si at 08:52 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
doug you need good data. One tree does not a hockey stick make ;-) Saying over and over that it is just 'the big picture see the trees dont mind the quality feel the width' is entirely missing the point. You are going to have to wait for Anthony's surface station report but it is coming! -
Si at 08:48 AM on 23 May 2010There is no consensus
And here is his comment after the conference: "I’ve just returned from the Heartland Institute’s Fourth Annual Climate Conference, at the Marriott Hotel in Chicago, where something very interesting was emerging: a clear counter-consensus on climate change. Of 700+ delegates, 400 or so were scientists in relevant disciplines – arguably more than on the IPCC’s much vaunted panel (after you allow for non-scientists, scientists in irrelevant disciplines, and dissenting reviewers). These scientists came from around the world, and from highly respected academic institutions. They were by no means unanimous, but all (except for two token Warmists) agreed that the IPCC “consensus” is deeply flawed, and that the policy prescriptions based on the IPCC’s work are extremely unlikely to deliver significant results." Looking forward to reading Robert Carters new book 'Climate -the Counter Consensus' -
Unprecedented Warming in Lake Tanganyika and its impact on humanity
johnd > The method they used to arrive at their conclusion was to measure an indicator (BSi)of the lakes productivity (at one sole location) and correlate that with already reconstructed global temperatures. You are missing a key detail, they also used the TEX86 temperature proxy to reconstruct lake temperatures for the past 1500 years. This is a separate method from the measurement of BSi; it is a temperature proxy, not a proxy of productivity like BSi. This yields three independent measurements: lake temperature record, global temperature record, and lake productivity. they found that all three of these measures correlate with one another, hence their conclusions. > If the objective was merely to make the connection between the lakes surface temperature and global temperatures, would not it have been better just to check the temperature records from relevant locations around the lake? The temperature record doesn't go back 1500 years. -
Si at 08:42 AM on 23 May 2010There is no consensus
This is relevant to this topic. It is from Roger Helmer talking before the 4th International Conference on Climate Change which he recently attended. Of the 80 speakers, I noticed that fully forty-five were qualified scientists from relevant disciplines, and from respected universities around the world -- from the USA, Canada, Mexico, Russia, Sweden, Norway, UK, Australia and New Zealand. All of them have reservations about climate alarmism, ranging from concerns that we are making vastly expensive public policy decisions based on science that is, to say the least, open to question, through to outright rejection of the Anthropogenic Global Warming (AGW) model. Several of these scientists are members or former members of the IPCC Intergovernmental Panel on Climate Change. But how do 45 sceptical scientists stack up, you may well ask, against the 2500 on the official IPCC panels? But of course there aren't 2500 relevant scientists on the IPCC panel. Many of them are not strictly scientists at all. Some are merely civil servants or environmental zealots. Some are economists -- important to the debate but not experts on the science. Others are scientists in unrelated disciplines. The Chairman of the IPCC Dr. Ravendra Pachuari, is a Railway Engineer. And of the remaining minority who are indeed scientists in relevant subjects, some (like my good friend Prof Fred Singer) have explicitly rejected the IPCC's AGW theory. Whittle it down, and you end up with fifty or so true believers, most of whom are part of the “Hockey Team” behind the infamous Hockey Stick graph, perhaps the most discredited artefact in the history of science. This is a small and incestuous group of scientists (including those at the CRU at the University of East Anglia). They work closely together, jealously protecting their source data, and they peer-review each other's work. This is the “consensus” on which climate hysteria is based. And there are scarcely more of them than are sceptical scientists at this Heartland Conference in Chicago, where I am blogging today. Never mind the dozens of other scientists here in Chicago, or the thousands who have signed petitions and written to governments opposing climate hysteria. Science is not decided by numbers, but if it were, there is the case to be made that the consensus is now on the sceptical side. -
Doug Bostrom at 08:24 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
...would not it have been better just to check the temperature records from relevant locations around the lake? You mean from the instrument shacks installed in the year 1000? No, that's not possible. You'd need a proxy for that. Maybe a core from the lake bottom? To summarize once again my objection to your objection, "I doubt it" is not a useful contribution. Si, you leave unaddressed the issue that Willis is obsessed with accuracy when accuracy is not the point. Same mistake as with the failed thermometer inspection project run by WUWT, debunked for the same basic reason Willis' critique of Tierney is pointless. -
Unprecedented Warming in Lake Tanganyika and its impact on humanity
Si >"And AGW getting stronger? More like DOA." Considering the theory was built up slowly and methodically over the better part of a century, I fail to see how it is "DOA". To exand on dhogaza's comment on what constitutes a significant percentage of climate scientists, please see John's post on scientific consensus. -
johnd at 08:10 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
doug_bostrom at 07:07 AM, actually a lot did go wrong with the samples, both at the top and the bottom. That is why only a portion of each was used, the equivalent of more than one core apparently discarded. As well, extrapolation was needed to date the bottom portion of the used portion as there was some reversal of age indicated at depth. -
dhogaza at 08:07 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
Si... "doug. I dont think Willis makes the mistake you mention. He is having a critical look at Jessica's paper - thats what scientists do." Scientists do it competently. Willis is no scientist, and his personal track record is one of incompetency, so I for one won't bother to read his piece at WUWT (or elsewhere). " I think there are rather more skeptical climate scientists than you realise. - Spencer, Michaels, Christy" I could've sworn there were at least a dozen (/snark). Si clearly doesn't understand that three (or a dozen) vs. thousands isn't exactly a large percentage ... -
johnd at 07:58 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
doug_bostrom at 07:07 AM, which particular congruency are you referring to? -
Si at 07:48 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
doug at 92 - I think you answer your own question! If Willis & the commenters at WUWT are right and the the data is poor then any conclusion is invalid. e and Phila, 94 and 95. I think there are rather more skeptical climate scientists than you realise. - Spencer, Michaels, Christy And AGW getting stronger? More like DOA. Maybe you meant climate science - yes it will get stronger. I think the AGW argument is basically is lost. But that does not mean that all climate science is duff. It does mean it should be completely separated from energy policy. The reason climate science gets such attention is that is has a large bill attached. And yes it may be irksome to have to reiterate basic science - but that's education for you (some people are still arguing about evolution). So let's keep discussing and reading - it's a fascinating subject! -
johnd at 07:43 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
doug_bostrom at 05:11 AM, there seems to be a lot of misunderstanding or confusion about what the findings of the report were. This is taken from the abstract, "We conclude that these unprecedented temperatures and a corresponding decrease in productivity can be attributed to anthropogenic global warming" http://www.nature.com/ngeo/journal/vaop/ncurrent/abs/ngeo865.html LOL. Has anyone happened to notice that this study is basically about fishing for sardines? The method they used to arrive at their conclusion was to measure an indicator (BSi)of the lakes productivity (at one sole location) and correlate that with already reconstructed global temperatures. If the objective was merely to make the connection between the lakes surface temperature and global temperatures, would not it have been better just to check the temperature records from relevant locations around the lake? It would have saved a lot of the contortions that it appears to be causing. -
Doug Bostrom at 07:07 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
Thanks johnd, that was indeed an interesting read. I'm unmoved by your speculations; Tierney's methodological explanation is vastly superior in actual detail compared to "maybe something went wrong with the samples." Besides which we still have the congruency to explain. -
johnd at 06:35 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
doug_bostrom at 11:52 AM, perhaps if we go back to the basics and look how the proxy was developed. A direct link was created between the deposits of biogenic silica (BSi) found in the core sample and lake temperatures. The lack of correlation for the charcoal obtained from the core was used to rule out rainfall as an influence on the rate of deposition. Other indicators as to whether the replenishment of nutrients from any of the many inflows or any part of the shoreline were excluded from consideration by the limited core samples taken that could have identified possible sources remote from the lake itself or activity close by. Logic dictates that if any material is being deposited in the sediments it must be replenished from somewhere unless it is in a constant decline, and if the rate of replenishment varies that would be reflected in the rate of deposition. If you haven't read this study referenced below you may find it interesting if read carefully, particularly the advice on site selection within the lake if undertaking paleoclimate reconstructions, the accepted methods they used to take multiple samples along transects, but in particular, I repeat, in particular, the extremely wide variation of the BSi content within the numerous samples collected. http://www.geo.arizona.edu/nyanza/pdf/Powers.pdf -
Doug Bostrom at 06:30 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
[let's be civil, please!] Sorry! That's what comes of not hitting "preview." Always good to be reassured someone's actually reading all our blather. :-) -
Phila at 06:13 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
[let's be civil, please!] Sorry! That's what comes of not hitting "preview." Thanks for the gentle reminder. -
Phila at 05:55 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
#91 "I think not. The more critical we are the better the science will be. That papers get picked over and pulled apart...." Yes and no. If someone like Lindzen is critical, that's one thing. But if someone who doesn't understand the basic concepts of AGW is critical, and routinely mistakes lazy contrarian speculation for a new and improved form of "peer review," that's not really useful, IMO. I think it'd great to have a "more robust science," and I'm sure everyone here agrees with me. But if skeptics want to contribute to that result, they need to become conversant with the basic science and the rules that govern it, at the very least. You can't simply leapfrog over these requirements and present yourself as a climatologist's peer or inquisitor. What I object to is not the desire for democratization, but the assumption that there is or should be no entrance fee, in the form of doing one's [let's be civil, please!] homework. I'm sure you'd like astrophysics and virology to be more robust sciences too, but I suspect you don't spend much time instructing scientists in those fields on First Principles. -
Unprecedented Warming in Lake Tanganyika and its impact on humanity
Si >"The more critical we are the better the science will be." Yes, but true scientific criticism generally comes from other practicing scientists, especially those in related fields of study. This ensures that those employing the criticism are well versed in topics relevant to the field. If scientists tried to address all the criticisms of amateur skeptics, they would be spending all their time rehashing basic principles and never moving the science forward. For sure, there are legitimate scientists on the skeptic side (Lindzen being one), but their number is tiny compared to those accepting the mainstream position. It seems that an inordinate amount of criticism of AGW comes from amateurs who feel that their every issue and misunderstanding must be addressed before the science should be considered robust. I can't think of any scientific discipline that holds itself to such an impossible standard. In the end though, I think you are right that it makes the science more robust. In that regard, it is telling that the scientific consensus supporting AGW has only grown stronger in the face of this overwhelming scrutiny. -
Doug Bostrom at 05:11 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
Thanks for the clarification (pun?) on Langenberg, Si. A lot of observations but apparently none to rebut Tierney's central finding, that of a temperature record closely resembling that produced by numerous other measurement methods from a diversity of other geographically dispersed situations. Now, one could say Tierney's wrong somehow, but that leaves hanging the question of why the record she's derived bears such an uncanny resemblance to so many others, which of course also mutually coincide. Any hypothesis to explain this resemblance should include a mechanism yielding such a set of coincident signals. We have that mechanism at hand, predicted by fundamental physics and apparently confirmed by a host of observations. At WUWT I read misplaced concern about data points as opposed to statistical lessons from data collections, innuendo about Mann, sophomoric remarks about "Hockey Teams" and the like but I see absolutely nothing that will coherently explain how Tierney's results are so closely congruent with what we expect to see and in fact have seen in numerous other data sets. So, no useful contribution, just a lot of "I doubt it" or elliptical departures from the objective of Tierney's work. No utility of the kind you refer to, Si, when you extol the virtues of the activities at WUWT and elsewhere. -
Doug Bostrom at 04:57 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
Si, you don't think Willis is swerving into misplaced concerns with absolute accuracy? Can you explain what he's writing about, if it's not absolute accuracy? Why are he and you, too, apparently so disturbed by by the relative paucity of calibration data? Regarding your later remark, the utility of criticism depends on its validity and ability to further progress. So far I've seen little evidence of that; Lindzen is about the best data point available but he appears to have become entirely fixated on a hypothesis that has proven unable to improve on others' work. -
Si at 04:41 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
Phila "The problem is that a small group of amateurs has decided to hold climate scientists to an impossibly high standard that most of them apply to no other field. Any science that tried to appease this degree of contrarianism would be doomed to stasis at best." I think not. The more critical we are the better the science will be. That papers get picked over and pulled apart (Teardown you call it in hardware) means that Climate Science will move out of the cosy club it has been and become a much more robust science. This site is helping in that by questioning your 'small group of amateurs' (I think Richard Lindzen et al might object to that description). -
Si at 04:27 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
doug. I dont think Willis makes the mistake you mention. He is having a critical look at Jessica's paper - thats what scientists do. I think he makes some interesting points and gets even better comments in the thread eg Hu McCulloch's- odo take a look. -
Si at 04:17 AM on 23 May 2010Unprecedented Warming in Lake Tanganyika and its impact on humanity
John the relevance of Langenberg to Tielney is that he is another young student studying the lake but comes to different conclusions - of course they are not attention headline grabbing ones but such is life. In brief (and not my summary but from Pat Moffat) • No evidence of increasing lake clarity as a result of secchi measurements since 1946 • The interplay of stratification and plankton productivity are not “straightforward” • Challenges O’Reilly’s assumption on the correlation of wind and productivity -the highest production is on the end of the lake with the lowest winds • A strong caution using diatoms as the productivity proxy (it is one of two different lake modes) • No ability to link climate change to productivity changes • More productivity from river than allowed for in Nature Geopscience article • Externally derived nutrients control productivity for a quarter of the year • Strong indications of overfishing • No evidence of a climate and fishery production link • The current productivity of the lake is within the expected range • Doesn’t challenge recent temp increase but cites temperature records do not show a temperature rise in the last century • Phytoplankton chlorophylla seems to have not materially changed from the 1970s to 1990s • Disputes O’Reilly’s and Verbug’s claims of increased warming and decreased productivity • Rejects Verburgs contention that changes in phytoplankton biomass (biovolume), in dissolved silica and in transparency support the idea of declining productivity. A large part of the lakes production may be picocyanobacteria
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