Arguments
Recent Comments
Prev 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 Next
Comments 115501 to 115550:
-
Riccardo at 18:25 PM on 10 July 2010Sea level rise is exaggerated
daniel, the paper shows two data sets and draw conclusions explicitly based on both. It really does not matter who actually collected the data. The large error in the sedimentary data does not imply an equivalent large error in the trend. Indeed, the latter is 0.2 mm/yr and assuming a comparable error for the tide gauges data the difference in the trends is still significant. Or do you think it's not possible to compare two different data sets? -
gallopingcamel at 15:21 PM on 10 July 2010Hotties vs Frosties?
What a simple question. How could anyone be other than a "Hottie"? Thanks to the brainwashing I get on this site, you can count me as a "Hottie" even though my wife might disagree. It is clear that increasing levels of CO2 in the atmosphere will cause warming. You folks are mostly with the IPCC that predicts a warming as high as +4.0 Kevin per doubling of CO2 concentration. IMHO +0.5 Kelvin is a much more likely figure. It is a shame that nobody is likely to be able to measure this quantity with any accuracy in my lifetime. Otherwise we could make some wagers. -
Sean A at 14:43 PM on 10 July 2010Hotties vs Frosties?
What a ridiculous, naive post. Of course the fervent hotties will say, "But we've already done all the necessary work, and the weight of evidence is overwhelming." And the fervent frosties will say, "They haven't proved anything. They have failed to address this and this and this. Their results are meaningless". And there is validity to both of these points of view. The heart of the ridiculousness is in that paragraph. The denialists are arguing in good faith! Ha! The fallacy of false equivalence -
daniel at 14:18 PM on 10 July 2010Sea level rise is exaggerated
Peter Hogarth at 06:10 AM on 10 July, 2010 Pete I can't quite tell if this comment was supposed to be taken as a backdown on Donnelly 2004 or if you intend to argue further with a graph of your own. If a backdown I acknowledge that it would be of this paper and this paper alone. I cannot then use this to say that all of Donnelly's work is invalid. But I do have some personal doubts and I feel that this discussion should prompt those reading on to look again with a more critical eye as to what is published in both in climate literature and other disciplines. -
daniel at 14:06 PM on 10 July 2010Sea level rise is exaggerated
Riccardo at 02:19 AM on 10 July, 2010 "The behaviour of the data should be clear and we should also come to the same conclusions reported in Donnelly paper," Yes it's clear, a simple linear regression of the box centres shows that the ~1mm/yr trend extends up to 2000AD. Donnelly implies that the tide gauge data is unusually high compared to 1300-1850 AD. But it clearly isn't since we use the same methods to obtain a "modern" paleo sample and find no significant uptrend in the data. Donnelly's rate error limits are 0.8-1.2mm/yr over 1300-1850. The simple linear fit of all the paleo data up to 2000AD has a rate within these limits (no detail as to how the limits are acieved in the first place). Are you going to go on again and say that a significant uptrend has been detected by the tide gauge when there is no high certainty paleo data to compare it to? Please save your breathe (fingers). "Indeed, you (and Donnelly) get a statistically significant trend of 1.0 mm/yr before about 1850." Well actually I don't know what statistical analysis Donnelly has performed on his trendline since it's not mentioned. I have simply tried to reconstruct it using visual markers. Linear regression of the centres of sample boxes 4-11 gives a rate of ~1.1mm/yr. Donnelly was trying to marry up the earliest tide gauge trends with a proposed linear trend through 1300-1850. ".... including it rises the rate at 1.2 mm/yr but both R and chi2 decrease." Can you do some calculations to show this please and by how much they decrease? I won't have time over the next couple of days. You then go on to say that you agree the paleo data doesn't support a recent acceleration and that nobody was claiming otherwise or at least not the paleo data alone. But they were claiming samples 4-11 did and I am showing that inclusion of sample 1 undermines that conclusion. The short term tide gauge data compared to the much less certain, long term paleo data is invalid and I believe I have shown by inclusion of sample 1 in a simple linear regression that short term variance is easily achievable amongst samples 4-11. After agreeing with me on the insufficiency of the paleodata you then say that the conclusion is solid. (Throws hands up in air as a sign of frustration). I didn't make an error by claiming "by this paper" Donnelly only provides sedimentary data. Do you think he collected the tide gauge data? Do you still think the conclusion drawn from the comparison between the two data sets is valid? -
daniel at 11:35 AM on 10 July 2010Sea level rise is exaggerated
KR at 02:02 AM on 10 July, 2010 "You have the 11 paleo proxies with a slope of 1.023mm/year, the recent tide data with a slope of 2.4 or 2.8mm/year. And you then fit all the data with a slope of 1.2mm/year?" Please read the graph and post carefully. Samples 4-11 (that's 8 count em... 8, have you read the paper KR?) have the Donnelly linear fit (psst... it's not a least squares fit) of 1.023mm/yr. I used visual indicators/markers from the Donnelly graph (fig 2.) to construct it, it rounds to 1.0mm/yr. The dashed portion is extrapolated for comparisons to the other fitted lines etc. The least squares I have fitted to all paleo data produces a 1.2mm/yr average long term trend over the entire 700 years (thats a slope just inside Donnelly's error bars.... pennies dropping yet?) "Modern levels of SLR are KNOWN to be ~2.4 mm/year." That's nice..... "Donnelly's fit of ~1 +/- 0.2 mm/year average over the 1300/1900 period still holds." It holds to 2000AD....... look at the graph KR "Perhaps, just perhaps, there were major swings in SLR between the Donnelly sample points" I am suggesting short term swings that lie within the error bars. They are easily there, as I keep asking you.... read paper.... look at graph. The fact that a shallow linear trend extends up until 2000AD with tide gauge data that deviates from it but remains within the large error estimates of the most recent paleo sample is more than enough evidence to support my critique of this paper. Such deviations could have easily existed "(although as Peter Hogarth points out, lots of other data indicate that this is not the case, filling in the spaces between these linear fit samples)" He tried using Donnelly 2006 and failed miserably, sure there are other papers and I need to find time to read them but my first impression was not a good one. "There are certainly no physical phenomena that we know of that could cause reversible SLR changes on that order." I don't know what you mean by "reversible" (probably some exaggerated claim about the short term trends I'm suggesting involving unicorn plasmas). There seems to be alot that the climate science community doesn't fully understand about the hugely complex system known as planet earth. I don't really care if you have or haven't found drivers for ancient SLR swings. You can't claim they didn't exist from an amateur non least squares line fit! I'm not saying that recent SLR can't be 2.4mm/yr or that the long term trend isnt ~1mm/yr +/- 0.2mm/yr. Actually KR.... if you read carefully.... I'm saying its 1.2mm/yr..... :0 ..... wha!!!??? "And - if we had a 150 year change in SLR of this magnitude in the previous 1000 years, the paleo data points wouldn't all be on the fit line!" I am moved to laugh... You mean like the centres of sample boxes 8, 11 and 10? "I suspect Peter will have something to say about this as well..." Yes that's right KR, if it wasn't for him we'd barely have a discussion. Why don't you let him do the talkin while you do some readin, not skimming. -
johnd at 10:01 AM on 10 July 2010Tai Chi Temperature Reconstructions
Peter Hogarth at 05:45 AM, tree growth, indeed any plant growth, is subject to a number of different conditions all being in place, the final result depending on how well balanced the combination is at any given period of time. Temperature is but one of those conditions. I think that once all the other factors have been adequately accounted for, then what is left over could reasonably be attributed to temperature. However the understanding of all the other factors is far from complete, the science is not settled, the understanding for some of the factors it is almost certainly less than adequate. It is difficult enough in controlled circumstances such as occurs in agriculture or in plantation forestry where soil and tissue testing and ongoing monitoring of local conditions is possible, let alone in some remote natural environment, even in real time. Trying then to establish how that combination of factors all came together at some distant point in time requires a lot more information then merely the width of the growth rings, information, some of which I am not convinced is even available. The fertilisation effects of CO2 have been known for over a century, trials in more recent times show that the effect is not uniform across all species, and is subject to other local contributing factors. Thus this contributing, and perhaps significant factor can only be adequately allowed for once it has been studied on the trees that are being used to correlate growth with temperature. This is vitally important because both CO2 and temperature are claimed to be directly related and thus it is necessary to separate and allocate each of the inputs. Much the same applies to all other inputs be they positive or negative factors. One additional factor that I have become aware during my reading on the subject of tree ring growth temperature relationship, is that the selection of trees to measure is far from random. It relies not only the selection of species, but the selection of individual trees whose growth is considered to faithfully represent a robust relationship between growth and temperature. This is referred to in Buntgen 2008. "Tree-ring width chronologies from 40 larch and 24 spruce sites were selected based on their correlation with early (1864–1933) instrumental temperatures to assess their ability of tracking recent (1934–2003) temperature variations." That may inspire confidence in some, but does the opposite for me. To sum up, I have always understood that temperature is an influence on all forms of plant, and animal, growth. However I have also been equally aware of all the other essential factors, thus once temperature reconstructions using tree growth rings started to be given prominence, I began having reservations as there didn't appear to be adequate understanding of the all the other factors. The emergence of the divergence problem was, and still is justification for such reservations. If it cannot be accounted for during recent times with all the access to high quality data and the ability to study the contributing factors in real time, what faith can one have that the same factors have been allowed for in the historical reconstructions. It is our individual acceptance of that which I think puts us at cross purposes, if we are that is, on the matter of the divergence problem. -
DarkSkywise at 09:58 AM on 10 July 2010Hotties vs Frosties?
villabolo #51: Online polls... humbug! (Not you, Baa Humbug. You aren't a poll.) :P We've recently had elections in the Netherlands and there were online polls showing 70-80% of the votes going to the anti-immigrant Freedom Party (who also believe AGW is a conspiracy to raise taxes, globally orchestrated by the dutch Labour Party - no, I'm not making this up), with even people vehemenly believing those figures. Of course, in the end, it didn't happen quite that way. Online polls really just show one thing only: people voting on online polls. Which, fortunately, is not the same as "our side slipping". ;) -
kdkd at 09:00 AM on 10 July 2010Hotties vs Frosties?
BP #40 Your argument is rather weird. You appear to be claiming that reductionism is the only valid approach to scientific method. As you can see here reductionism becomes much less useful in situations with "higher amounts of complexity, including culture, neural networks, ecosystems, and other systems formed from assemblies of large numbers of interacting components". You'll find a large literature refuting your implied assertion that reductionism is the only valid approach if you look for it. The only people who claim that pure reductionism is a valid approach for studying complex systems are those who have not had to think deeply about the problem. -
villabolo at 08:24 AM on 10 July 2010Hotties vs Frosties?
John, I beg to differ with you. I have observed and posted on WUWT and one of my first experiences was to have a poster say that if I could not correctly spell the name of another poster (Anna vs Ana) then I wasn't likely to have any understanding on the subject matter. While this was the worse example, there were plenty others who were nasty in proportion to the civil ones. Also the major difference between the rudeness of "Skeptic" vs "AGW's" can be very easily spotted on the commentary section of any site that has an article on GW or even You Tube. In other sites or in You Tube, whenever a video is posted on either side of the issue, the "Skeptics" come out in full force, overwhelming the number on "AGW's". And the majority of them range from rude to extremely rude. Take a look John, and you'll find that there is NO EQUIVALENCY whatsoever. By the way, MSNBC is taking a poll of people asking for their opinion on whether the British Panel's exoneration of scientists on "Climate Gate". Anthony Watts is on the warpath asking his readers to vote. Our side has been steadily slipping. From 42% in our favor and 58% against, yesterday to 39.1%<60.9% as of this moment. Some of you may want to put in your two cents worth. Sorry for the long link. http://msnbc.newsvine.com/_question/2010/07/07/4630892-are-you-satisfied-with-the-british-panels-conclusion-that-while-climategate-scientists-were-not-always-forthcoming-their-science-was-sound?pc=20&sp=180&threadId=1004983&commentId=15443603#c15443603 -
Peter Hogarth at 06:10 AM on 10 July 2010Sea level rise is exaggerated
daniel at 19:25 PM on 9 July, 2010 Daniel, thanks for the chart. It would take me a little longer to enter the data and do one with error envelopes and the tide gauge data, but I think we now get a better explanation of why this misunderstanding has rolled on... -
KR at 05:56 AM on 10 July 2010Sea level rise is exaggerated
johnd - sorry about that; I really need to get off this cold medicine! That should be a reference to daniel. -
NickD at 05:54 AM on 10 July 2010Hotties vs Frosties?
"...would these green folks advocate going against Nature to artificially cool the Earth?" So if I reduce the amount of fossil fuels I use,and granting your hypothetical to be true, how exactly am I "artificially" cooling the Earth? Also, if I have an iced latte, am I helping getting rid of the waste heat? -
Peter Hogarth at 05:45 AM on 10 July 2010Tai Chi Temperature Reconstructions
johnd at 03:43 AM on 10 July, 2010 John, I think we are at cross purposes on Divergance Problem. I have not missed the purpose of this paper or the others, I'm fairly familiar with them. I have not denied the DP exists, just tried to point out that it is an an effect most likely unrelated to temperature, ie the validity of tree rings as temperature proxies, away from significant SO2 influence and where other factors such as moisture are accounted for, is solid, as in your comment 51, as in Buntgen. Are we agreeing on this? The correlation of growth with instrumental temperature records for the Buntgen and other studies I referenced in my first comment is compelling and credible (or I think so). The correlation with CO2 less so, though again this is a recognised factor, and I have papers on this also. Have a look at the ones supplied so far, they contain a lot of pertinent information. Your suggestion of competing SO2 and CO2 is opinion. I don't dismiss it, but without evidence, I take it as such. The seasonal and year to year growth patterns and seasonal temperature are relevant evidence here, as correlation is seen at this level. In terms of Sulphur absorption you should read the references I supplied. The tree ring growth, measured SO2 atmospheric levels, and sulphur levels in the woody growth itself are direct evidence concerning your "extended residence time" suggestion. SO2 is one potential explanation for DP, based on the data available, the references I cited cover this, and Buntgen does (briefly). One other specific factor mentioned is decreasing moisture (climatic). It may well be combinations of several factors which are challenging to disentangle, but the experts would not "dismiss" any of them, and I don't either. -
johnd at 03:59 AM on 10 July 2010Sea level rise is exaggerated
KR at 02:02 AM on 10 July, 2010 johnd - Thank you for the chart. - ????????????????????????? -
johnd at 03:43 AM on 10 July 2010Tai Chi Temperature Reconstructions
Peter Hogarth at 22:01 PM on 9 July, 2010, I think you missed the overall findings of Buntgen 2008 by focusing on certain aspects only. First the study acknowledges that the DP exists right at the beginning:- "Abstract Evidence for reduced sensitivity of tree growth to temperature has been reported from multiple forests along the high northern latitudes. This alleged circumpolar phenomenon described the apparent inability of temperature-sensitive tree-ring width and density chronologies to parallel increasing instrumental temperature measurements since the mid-20th century." Secondly they acknowledged the concerns such evidence brings:- "If DP is widespread and the result of climatic forcing, the overall reliability of tree-ring-based temperature reconstructions should be questioned." It appears to me that what the study set out to achieve was to determine whether the DP is climate related or not. My understanding of the results is that from the data they analysed, they found that there was no DP evident in the trees they studied. Thus my interpretation of their conclusions is not that the DP is non-existent, but that it most likely is not climate related. Whether or not it is widespread cannot be determined simply by what has been the case at one study site, but it certainly has been found at a number of sites as mentioned in the abstract, thus I believe it is real. However, it appears that the Buntgen 2008 study didn't consider one possibility, that being that the consistent growth they found may be the nett result of two opposing factors, namely CO2 and SO2. It didn't even mention what the growth response to rising CO2 levels was to be expected from the trees under study. These are matters that I believe have to be accounted for before any such study can be seen as complete. Thus I don't believe that Buntgen 2008 has really advanced the understanding of the DP at all, hence my comment of it being of limited use. Therefore what causes the DP? Something obviously does, and apparently that something still hasn't been identified. I suggested SO2. You appear to both acknowledge the effects of SO2 and dismiss it because it is short lived. What you are missing is that once the SO2 has been absorbed by the vegetation, the sulphur so released is deposited to the soil below where it remains. Where "acid rain" occurred in farming areas, the sulphur was stripped from the soil along with the other nutrients that were taken up by the plants and animals that were being farmed and initially the extra sulphur was actually beneficial. When SO2 emissions were reduced, farmers were forced to add additional sulphur to their land in order to maintain production. Such stripping of sulphur from the forests does not occur unless logging takes place, and thus if the sulphur has built up to the extent it has effected tree growth, it will remain there for an extended time. I think any study that tries to tie tree growth to any climatic indicator must firstly reference any research that examines how the trees under study respond to changing CO2 levels, especially to levels less than the current ambient where historical growth patterns are being analysed, and secondly other relevant "pollutants" both from anthropogenic and natural sources especially where there may be an accumulation over time. -
RSVP at 03:17 AM on 10 July 2010Hotties vs Frosties?
According to this article, Hotties are green. But if global warming (hypothetically) proved to be due to Nature, would these green folks advocate going against Nature to artificially cool the Earth? Meanwhile, all those lattes are generating waste heat which of course has nothing to do with global warming.Response: If global warming proved to be due to nature, then all our CO2 emissions are not causing warming. Set aside for the moment the question of how all the trapped heat directly observed by satellites and surface measurements is not causing warming. If we believe CO2 is not causing warming, then reducing our CO2 emissions will have a minimal effect. You can't say adding CO2 has no effect but not adding it will have an effect. -
Hotties vs Frosties?
BP, This is a blog, we aren't performing the scientific method here, that's for practicing scientists out in the field producing peer-reviewed research. We are reviewing the evidence that is produced by that science to gain a broad understanding of our world and where we are headed. This is inherently a "big picture" approach. To abandon this approach is to say that science can make no broad statements about how the world works; it is reduced to a meaningless excercise in data collection. -
apeescape at 02:33 AM on 10 July 2010Hotties vs Frosties?
We need to find a label for the people who average out the opinions of the frosties and hotties. Is "air conditioneries" apropos? :) "The frosties look at the data without any underlying model, and see no trend. The hotties look at the data in the light of their models, and see something different. The point of difference is not that they see different things, it is the presence or absence of an underlying model of what they see." This passage could be taken as: frosties are unbiased, or frosties are unscientific. I think most people that get serious about this issue has a model in their heads. I'm not sure why the hotties (or the frosties) are assumed to not look at "the other side." -
Marcus at 02:26 AM on 10 July 2010Hotties vs Frosties?
Ba Humbug, we actually had about 40 years of warming to go on between 1950-1990-warming which couldn't be explained by any *natural* cause that we could see, not the less than 15 you claim. We also had the strong knowledge of the IR-absorbing effects of CO2 & Methane to come up with a reasonable hypothesis for why the planet was warming in the absence of increased insolation. The warming in the 1st half of the 20th century was well explained by the rapid rise in sunspot numbers over this time period. What you seem to be doing, Humbug, is *assuming* that the Climate Scientists who did all the initial leg-work were some kind of stupid panic-merchants. This is just the kind of anti-intellectualism I've come to expect from the rabid fringe of the Notties Movement. -
Riccardo at 02:19 AM on 10 July 2010Sea level rise is exaggerated
daniel, I did not follow your previous discussion so i'm basing my comments on the last couple of your comments. In particular, the claim "I think it is fairly obvious from this graph that there is no statistically significant uptrend in the last 150 years detected by this paper." (emph. mine). The behaviour of the data should be clear and we should also come to the same conclusions reported in Donnelly paper, which is: "A linear rate of rise of 1.0 ± 0.2 mm/year intersects all the 2s uncertainty boxes of the record from the 14th to the mid-19th century (Figure 2). Linear regression of the NYC tide-gauge data reveals an average rate of SLR of 2.8 mm/year from 1856 – 2001 A.D. Coupling the Barn Island record and regional tide-gauge data indicates that the rate of SLR increased to modern levels in the 19th century (Figure 2). [...] The NYC tide-gauge data further support the late 19th century timing of the SLR increase. Linear regression of segments of the NYC tide-gauge data indicate an increase in the rate of SLR from about 1.0 mm/year between 1856 and 1878 to 2.4 mm/year between 1893 and 1921 A.D. [Donnelly and Bertness, 2001]." Indeed, you (and Donnelly) get a statistically significant trend of 1.0 mm/yr before about 1850. The last data point lies above this line, although barely statistically significant; including it rises the rate at 1.2 mm/yr but both R and chi2 decrease. Statistics indicates that there has been a change in slope but a weak conclusion, i'd say. Adding the NYC tide gauge data between 1893 and 1921, the 2.4 mm/yr line nicely match sample #1. Then, sure i'd not say that there has been an acceleration after the 19th century from sedimentary data alone, afterall there's just one data point supporting this conclusion. Note that not Donnelly nor John in this post claimed otherwise. But overall, i.e. including all the data presented in the paper, the conclusion of an increase in the sea level rise rate from the late 19th century is solid. Back to you claim quoted above, i think that the mistake is in the last few words "by this paper", you should have referred only to sedimentary data. -
chris at 02:05 AM on 10 July 2010Hotties vs Frosties?
chris at 02:00 AM on 10 July, 2010( ooops...I meant: "...particularly apparent in a rather brutalist deductive approach....)" also apols for the long post. -
shawnhet at 02:05 AM on 10 July 2010Hotties vs Frosties?
Oops, I forgot my last point, which was that the primary points of disagreement are IMO: 1. the role/effect of natural variations on temperature(including what the natural "forcings" on temp are) and 2. the validity of the observational record. -
KR at 02:02 AM on 10 July 2010Sea level rise is exaggerated
johnd - Thank you for the chart. A question of note, however: You have the 11 paleo proxies with a slope of 1.023mm/year, the recent tide data with a slope of 2.4 or 2.8mm/year. And you then fit all the data with a slope of 1.2mm/year? Modern levels of SLR are KNOWN to be ~2.4 mm/year. Donnelly's fit of ~1 +/- 0.2 mm/year average over the 1300/1900 period still holds. Perhaps, just perhaps, there were major swings in SLR between the Donnelly sample points (although as Peter Hogarth points out, lots of other data indicate that this is not the case, filling in the spaces between these linear fit samples). There are certainly no physical phenomena that we know of that could cause reversible SLR changes on that order. The data provided in this paper still demonstrates an average (read that word again) average SLR of 1+/-0.2 mm/year for 1300-1900. I think you are really missing the point. The current SLR is known to be ~2.4 mm/year. Donnelly's paper establishes that over the period of 1300-1900 it averaged ~1+/-0.2 mm/year. Therein lies the conclusions of interest, that SLR rates are changing. Are you arguing that the current SLR is NOT 2.4mm/year??? Then you need to disprove all of the satellite and tide data. Are you arguing that it did not average ~1+/-0.2 mm/year for the 600-700 years prior to the 1900's? Then you are disagreeing with yourself - your reconstruction and graph support Donnelly, well within his error bars. And - if we had a 150 year change in SLR of this magnitude in the previous 1000 years, the paleo data points wouldn't all be on the fit line! I suspect Peter will have something to say about this as well... -
chris at 02:00 AM on 10 July 2010Hotties vs Frosties?
Berényi Péter at 01:11 AM on 10 July, 2010 Well your first post was a misrepresentation as I indicated Peter. You've changed the subject into something a little more interesting. If we are interested in a subject with important issues around (i) an evidence-base and (ii) causality, we will always (if we wish to address the subject honestly) "look at the big picture". For example we might be interested in the cause of lung cancer and more specifically the causal relationship with smoking ciggies. The "big picture" might be encompassed within the following knowledge base (theory) and empirical evidence: (i) A vast epidemiological effort has established a correlation between ciggie smoking and lung cancer [EMPIRICAL]. (ii) Our understanding of the molecular basis of some forms of cancer encompass the idea that certain molecules (carcinogens) can damage DNA beyond the ability of somatic cellular repair machinary to correct this, and that expression of mutant forms of important cell cycle control proteins can result in cell proliferation and cancer (THEORY based on EMPIRICAL observation and basic Mol. Biol.) (iii) We can observe these mutations in proliferated tissue in biopsies from lung cancer patients. [EMPIRICAL] ...and so on.... Now of course we could decide to eschew the "big picture" and focus on sub-elements of the subject where there might be uncertainty. That's fine; it's the areas of uncertainties that scientists like to inhabit since that's where discoveries will be made. The problem is when these sub-analyses are used to attempt to misrepresent the relationships that are well understand from a "big picture" perespective; e.g. (a) Here is a group of heavy smokers that don't have lung cancer. Clearly smoking doesn't cause lung cancer. (b) I've analyzed DNA from lung biopsies of ths cohort of lung cancer patients. I can't find any evidence of mutations in important cell cycle regulatory elements in these patients. Clearly cancer isn't caused by the mutagenic effects of carcinogens. ....and so on.... Your OHC example is somewhat related. We know that global warming is occurring, we can measure this in the real world and examine its consequences (EMPIRICAL), and can understand the causal relationships within a large body of THEORETICAL knowledge (based on earlier EMPIRICAL analyses). As you say, there are a number of OHC analyses. None of these is inconsistent with our understanding of global warming and its causes and consequences. The important issues with OHC currently center around our ability to measure this reliably, especially in relation to short term variability. These are fascinating issues and of intense interest to the scientists who study these. However there is a limit to how much we can productively "gnaw over" these on a blog such as this. My feeling is that an essential problem with focussing on the sub-themes of a broad set of analyses that bear on a subject (like global warming in response to raised greenhouse gas concentrations) is that it leads to the temptation (particularly apparent in a rather brutalist inductive approach) that one selects a particular set of data or analysis in order to attempt to precondition a conclusion by "loading" the premise. That's not a problem for science and scientists who love to wallow in areas of uncertainty. Unfortunately, as in the smoking example, focussing on the sub-themes can be used to cheat Joe Public out of his democratic right to a reliable representation of the subject (the "big picture"). Focussing on the uncertainties in sub-themes is the standard way of misrepresenting the science, as is described quite nicely in the paper I linked to above. As long as we're aware of that evcerything's fine and we can argue about OHC to our hearts contet! -
shawnhet at 01:58 AM on 10 July 2010Hotties vs Frosties?
John Brookes:"I don't think there is any hope for the lunatic fringe on either side. If your starting point is that the people on the other side are evil incarnate, then you won't move from that. But for the rest of us, maybe there is some common ground. Can we find the points on which we agree? Much more importantly, can we pinpoint the exact places where we disagree?" I agree that there is no talking with the extremes on either side. As to whether there is common ground, amongst the reasonable folks, there is much more than you seem to think IMO. Generally, the disagreement for these folks is btw the Hotties (a doubling of CO2 will cause 2-4.5C of warming) and the Warmies(btw 0.5-2C). Probably >90% of the reasonable people in both camps will fall somewhere in these two ranges. Cheers, :) -
NewYorkJ at 01:43 AM on 10 July 2010Hotties vs Frosties?
"But for the rest of us, maybe there is some common ground." This might work in some political environments, but not for science. Science is not about finding common ground with some arbitrary opposition. http://en.wikipedia.org/wiki/Argument_to_moderation -
Berényi Péter at 01:11 AM on 10 July 2010Hotties vs Frosties?
#12 chris at 19:55 PM on 9 July, 2010 That was a rather unnecessary post Peter since "looking at the big picture" means taking a broad perspective of all of the data and information that bears on an issue. It doesn't have anything to do with "pictures" in the sense that you've misconstrued it No, it was not unecessary. The article above is about different ways of perception. One way is trying to visualize all of the data and information that bears on an issue. It is a holistic approach, has great pedagogical value but has nothing to do with the scientific method. Most of the people here seem to be preoccupied with the big picture. That is, if some detail would not fit, they just tend to ignore it. Any OHC (Ocean Heat Content) history reconstruction with an upward slope fits into the big picture nicely. However, there are a number of different OHC reconstructions with this general property which are still inconsistent with each other. This is the point where things start getting interesting, but it is also the point where folks here tend to lose interest. The same with UHI (Urban Heat Island) effect on surface temperature history. The effect is shown to be huge everywhere locally, even on pretty rural sites like Barrow, Alaska. We also know that world population has doubled twice since the beginning of last century, therefore on average local population density has increased fourfold everywhere. Still, no one is inclined to take a closer look at the UHI effect on surface temperatures, because a large downward adjustment of the trend would make it unfit for the big picture. There are always multiple lines of evidence you know and none of them can be scrutinized thoroughly, in itself, because people insist all of the data and information that bears on an issue should be taken into account. But that is not so, science does not work that way. Each piece of evidence should be able to stand on its own right, irrespective of any support that may or may not come from another domain. Preoccupation with robustness springs from the same vein. It fancies even if some of the claims supporting the big picture would come out as untenable, there are still multiple, independent lines of evidence, so the big picture should be correct irrespective of any flaw. It is an inherent property of pictures. You can remove any pixel you want, it does not do much harm to the picture. You can even remove all the pixels at the same time, but khrrrm, wait. 'Well! I've often seen a cat without a grin,' thought Alice; 'but a grin without a cat! It's the most curious thing I ever saw in my life!' -
nealjking at 00:56 AM on 10 July 2010Hotties vs Frosties?
John Brookes' original bottom-line point is worth re-emphasizing: People who think that the argument that AGW is happening is based on just looking at the data will be unlikely to see a trend worth worrying about: It looks vaguely random. However, the concern comes from: 1) Having a physical model of the world and the climate, based on our understanding of the physics; 2) Deriving a trajectory of temperatures (a trend) based on that understanding; and 3) Looking for DISCREPANCY between the calculated trend and the measured data. In Popperian terms: You can never PROVE the theory, you can only look to see if the data DISPROVE the theory. If the data fail to disprove the theory, it's a success. At least for now. -
rocco at 00:55 AM on 10 July 2010Hotties vs Frosties?
And here we go again: http://www.youtube.com/watch?v=sGArqoF0TpQ -
Lou Grinzo at 23:56 PM on 9 July 2010Hotties vs Frosties?
I think there's a timing aspect to climate change that's far too often overlooked, and it explains why many hotties (including me) feel such an overwhelming sense of urgency. There are two layers of latencies, arranged sequentially, that come into play. The first is the human one: How long will it take us to realize what all that CO2 is doing and then go through the political process and take sufficient action to act in our own best interest? Obviously we're still in this stage. The second latency is the Earth System itself. The extremely long lifetime of CO2 in the atmosphere is about as inconvenient as truths get. We've all seen the projections that say if we stopped all CO2 emissions today we'd experience continued warming for the next X years. (Someone fill in the exact number; it escapes me at the moment, but I know it's uncomfortably large.) An apt, albeit grisly analogy that I think describes the timing of our situation: Continuing to emit CO2 at anywhere near the current BAU level is NOT the equivalent of refusing to believe a stove is hot and touching it anyway. In that case, we can rely on our reflexes to prevent very serious harm. What we're doing is instead deciding to put our hand flat against the hot stove and hold it there for agonizing minutes. In other words, if we wait until virtually everyone is convinced that AGW is real and has to be dealt with, it will be far too late to avoid an enormous amount of pain. We simply can't overcome those two layers of latencies quickly. Decarbonizing modern economies (including some developing ones, like China) will take a long time, likely decades, and then we'll still have to deal with all that CO2 we've already emitted. And if decarbonizing includes completely shunning coal and the cooling effect we get from its extremely short-lived sulfur emissions, we would face a big surge in additional warming. That's all without invoking the truly nightmarish scenarios, like defrosting permafrost and methane hydrates to add a big, additional pulse of methane and/or CO2 to the mix. Sounds like a bad 1970's disaster movie, doesn't it? Sadly, it's the situation we're in. If you accept some very basic points -- the long lifetime of atmospheric CO2, the warming it causes, the basic characteristics of societies and politics -- then I don't see how anyone can escape the conclusion that further delay in reducing our CO2 emissions would put us on an almost unimaginably bad path. -
chris at 23:22 PM on 9 July 2010Hotties vs Frosties?
Baa Humbug at 23:06 PM on 9 July, 2010 Actually, now that I've read my post again, I accept that you do have a point. I was considering the fact that there is (happily) a dearth of women that actually engage in anti-science efforts efforts of the sort that attempts to winkle dodgy analyses into the scientific literature, or participate in "alternative" "non-science" "climate meetings", or are prominant in hounding climate scientists. That contrasts with the very large number of women that do real climate science. I accept however that I shouldn't equate this group (the anti-science one) with "frosties" across the board. As John makes clear in his top post, "frosties" refers more generically to those that dispute the science and may do so with good faith. So my apologies. I was referring to the rather more "hard core" "frosties".... -
Tony O at 23:19 PM on 9 July 2010Hotties vs Frosties?
If you are an alarmist, what does that make me? A rabid doomsayer. -
carrot eater at 23:14 PM on 9 July 2010Hotties vs Frosties?
and Humbug, along the same lines: the wording of the various IPCC reports from 1990 to 2007 reflect the increasing confidence in the observation of warming that is possible, as time passes. Meaning, in 1990 you have some confidence that something is happening along the lines of what you'd expect from the physics. By 2010, you have much more confidence. Either way, it's beyond silly for you to say "because I was sitting on the fence in 1992 while somebody else had more confidence than me, I'll now refuse to re-assess the situation even as everything advances" -
chris at 23:12 PM on 9 July 2010Hotties vs Frosties?
Baa Humbug at 23:06 PM on 9 July, 2010 I didn't consider I was being controversial Baa Humbug. That's a statement of fact isn't it? As in all areas of science there is a high representation of women. That obviously applies to climate science too (have a look at authors of climate science papers). I can only think of one female climate scientist that would be considered part of the anti-science group, whereas ther are obvioulsy lots of middle aged gents that are (for example peruse the list of speakers at the recent Chicago "alternative" climate science event). Clearly the "alternative" approach to climate science (if I can put it kindly) exemplified by the latter grouping isn't very attractive to female scientists. -
carrot eater at 23:09 PM on 9 July 2010Hotties vs Frosties?
Humbug: As I said, when Hansen spoke in 1988, he was reviewing the previous 30 years. And he had physics on his side. If you like, you can go and do the statistics working backwards from 1992 or 1990 or 1988, and see how far you have to go to reach a statistically significant trend, if you ever find one. As for CO2 being the dominant contributor: be careful how you phrase that. At the moment, it's the single biggest factor in how the temperature is changing over the long term. But it doesn't always have to be. If the sun goes and does something wacky, then it will be the sun. If a string of massive volcanic eruptions go off, then it will be that. If our pollution habits strongly change such that aerosols increase very rapidly, then it would be that. The point is, you have some ability to quantify all the forcings, and see what the relative magnitudes are. -
chris at 23:06 PM on 9 July 2010Hotties vs Frosties?
Baa Humbug at 22:56 PM on 9 July, 2010 Chris: Well I accept that you and many others accept CO2 to be the dominant contributor to earths surface temperature, but I and many others aren't so sure. Just to clarify Baa Humbug, I didn't say that. I said "that it is a dominant contributor to the Earth's surface temperature...". I don't think anyone could argue with that. Obviously Earth orbital cycles are dominant contributions to Earth temperature during the late Quaternary, as are periodic extraterrestrial impacts, massive tectonic events and the progressively increasing solar output through the entire evolution of earth history... -
Baa Humbug at 23:06 PM on 9 July 2010Hotties vs Frosties?
chris at 22:44 PM on 9 July, 2010 says.. "Very few women seem to have the stomach for the knowing deception and dishonesty that characterises much of the efforts of the "frosties"." Yeah good one Chris, really constructive that was. Tell you what, please disregard my reply to you, you and I can't have a civil discussion. People in glass houses. -
Baa Humbug at 22:56 PM on 9 July 2010Hotties vs Frosties?
Thnx for the replies carrot chris and cb. I wasn't debating the validity of AGW at my comment #16. I merely pointed out that if 15 years of data is hamstrung with noise, as Marcus stated, then that 15 years must apply at all times. carrot: yes Kyoto the meeting was held in 1997, lets allow a couple of years at least for lead up time ha? remember the Rio Earth summit was 1992. I would have thought any global T data from 1976 to 1991 was a 15 year stretch full of statistical noise, just like it is now, no? Chris: Well I accept that you and many others accept CO2 to be the dominant contributor to earths surface temperature, but I and many others aren't so sure. That is a fact that needs to be acknowledged and we need to work on that as Brookes is admirably trying to do now. CBDunkerton: With all due respect, your post at #23 is exactly the reason why this debate seems endless. "No remotely rational scientist" and "sceptics position is becoming incredibly thin" isn't going to cut it with me or any other sceptic. -
chris at 22:48 PM on 9 July 2010Hotties vs Frosties?
carrot eater at 22:42 PM on 9 July, 2010 "and for what it's worth, the UAH record is maintained by frosties ...oops! When I wrote "...NOAA, NASA Giss, UAH...", I meant "....NOAA, NASA Giss, UEA..." (I was being accidentally acronymonious!) -
chris at 22:44 PM on 9 July 2010Hotties vs Frosties?
Incidentally, the term "hottie" might be a little problematic since especially here in the UK it has a rather specific meaning ! Which brings to mind one of the distinguishing features of a science (like climate science) that has a heavy "anti-science" "deadweight" dragging along behind it, namely that the anti-science group are massively gender-weighted (usually rather unprepossessing middle, to late middle aged men for which the term "hottie" doesn't spring to mind!). It's quite striking in comparison to climate science where as in other real science disciplines, there are lots of female scientists, many in prominent positions (one can determine this by looking at author lists on scientific papers in climate science). This is an important point I think. Women form a very significant proportion of the science effort, and in my experience are (just like male scientists) attracted by the hands on satisfaction of experimentation, the intellectual rewards and the sheer pleasure in finding stuff out and contributing to progress in important areas. Very few women seem to have the stomach for the knowing deception and dishonesty that characterises much of the efforts of the "frosties". That's not to say that there aren't a few female bloggers that would be characterized as "frosties"...... -
carrot eater at 22:42 PM on 9 July 2010Hotties vs Frosties?
and for what it's worth, the UAH record is maintained by frosties. -
carrot eater at 22:40 PM on 9 July 2010Hotties vs Frosties?
chris: Anybody can take the existing data sets and analyse them in their spare time, with no funding at all. And I do note the asymmetry here, in who does something constructive with those data, and who does not. But the original language was "collect" their own data. Meaning, actually set up new weather stations, all over the world, suitable for measuring long-term climate trends. That's just not something that private industry or private individuals can be realistically expected to do. Though I could imagine private individuals doing something much less ambitious - maybe set up three stations in different sorts of locations in the same area. On a side note, not everybody realises this, but the US government has done this themselves - because of concerns over the existing network of stations, they've set up a new network called the CRN. These are fitted with modern instrumentation, and are specifically designed and maintained with climate in mind - far away from any urban heat islands, and to be kept immune from station moves and other disruptions. -
chris at 22:05 PM on 9 July 2010Hotties vs Frosties?
carrot eater at 20:33 PM on 9 July, 2010 To be fair, it's a little unreasonable to expect anybody to just set up a brand new global network of weather stations. On the other, other hand, one might ask more generally "why not"? Much of the data from weather stations is widely available, and more detailed access to the data can be purchased at a rather trivial cost (e.g. in relation to the funds available to oil companies or corporate-funded "think tanks"). But the only people doing these analysis outside of the NOAA, NASA Giss, UAH are well-informed and clearly scientifically literate individuals whose analyses have appeared on several blogs. Why don't the "frosties" have a go at this (as opposed to attempting to insinuate wrong-doing with pictures)? The last time I checked (maybe a couple of years ago) US federal funding for direct climate science was around the same level as for nanotechnology (around $1000 million p.a.; it may well be higher now, but probably in a similar proportion to nanotechnology whose level it seems to roughly track). This is not a large amount by any means, and if the corporate sector (especially oil/gas/coal) truly considered that the science is somehow unrepresentative of "reality", then they could easily have funded a very major scientific initiative to address this. But they didn't and don't; instead they give small funds to individuals and organizations that misrepresent the science.......go figure! -
Peter Hogarth at 22:01 PM on 9 July 2010Tai Chi Temperature Reconstructions
johnd at 04:41 AM on 9 July, 2010 Your implication that I am unfamiliar with basics of plant biology, or that the researchers I cited do not understand plant growth, or even that I might not read my own references is presumptuous. Science please. I read the section of the book you cited and there is nothing new here, but then it is 24 years old. You are correct to say SO2 is an important factor. Many will remember much concern about SO2 when “acid rain” and tree die-back in Europe was becoming a major climate concern in the late 1970s and 1980s. EU emission controls have now dramatically reduced atmospheric Sulphur levels (legislatively driven change is possible). However I disagree with your logic and dismissive conclusions. You claim to have read Buntgen 2008, but you can not have read very carefully. You state "all it basically confirms is that there is a divergence problem by examining data" In fact what it says is "Indication for an unusual late 20th century DP (Divergence Problem) is thus not found" and it repeats this conclusion several times, it is the main point of the paper, and you missed it? You claim Buntgen does not account for SO2. You must have missed his reference to “effects of airborne pollution” as one of the possible causes of DP and the references he cites which specifically look at SO2. I have read these also. You also seem to claim that SO2 is not factored into tree ring studies. I (or anyone) can easily falsify this. The negative effects of SO2 are well known and well documented and have been studied for more than two decades. In some heavily polluted regions the effects of SO2 on trees were severe, and caused reduced growth and tree ring width for around a decade after the 1970s, or were even a factor in mortality. Tree ring researchers are of course very aware of this. For example see Elling 2008 which shows highly significant effects of SO2 on tree growth in Southern Germany, Rinne 2010 refers to the effect of SO2 on growth, and describes the reduced growth episode in late 20th Century corresponding to pollution. Also Zhu 2009 which looks at the strong correlation of temperature and tree ring width (in North East China), but mentions that “a study based on tree-ring width in central Japan (Yonenobu and Eckstein, 2006) did not track such a warming trend, probably due to the consequence of anthropogenic SO2 emissions”. Also Rybnicek 2009 which states “The regional standard tree-ring chronology shows a decrease in the radial increments starting at the beginning of the 1970s and ending at the end of the 1980s”. “The main cause of this significant decrease is most probably the heavy air pollution load, mainly SO2 pollutants in the 1970s” “with the current air pollution load the climatic conditions are the factor determining the resulting effect of the synergic influence of the stressors on the stands” (ie recent changes are now down to temperature and precipitation). We should remember that anthropogenic SO2 pollution is wind transported, regional, and relatively short lived. We should also remember that high levels of SO2 decrease tree ring growth. This is why many studies suspect SO2 of being a possible cause of the Divergence Problem. In less polluted areas where Sulphur content is low Ulrich 2009, the dominant factors in tree ring growth are temperature and precipitation, whether in Europe Koprowski 2009 or elsewhere. For many species we see high correlation between increasing temperature and wider tree ring width (see the references). This is why tree rings are such a good proxy and this is why the DP mattered, and why recent work (Buntgen etc) is important. To round this off, are there are any general correlations between long term trends of global SO2 emission levels Smith 2010 and the growth trends in the tree ring studies? No, we see almost the opposite.
I am therefore worried that you are so dismissive of this work on tree rings, and draw conclusions (based on limited reading) which appears pre-judged. I suggest you start with an introduction and please read the references supplied.
-
Donald Lewis at 21:29 PM on 9 July 2010Hotties vs Frosties?
carrot eater (@15) I wasn't trying to be fair. I was making an observation, and trying to characterize John B's frosties. -
CBDunkerson at 21:25 PM on 9 July 2010Hotties vs Frosties?
Baa Humbug, in addition to carrot eater's points... please note that the 1970s were FAR from "early" in the debate over human induced global warming. That started around 1900 when Arrhenius's projections of warming from industrial CO2 emissions were dismissed based on a number of assumptions (e.g. single layer readings, saturation, ocean uptake) which have each been disproved over the subsequent century. The 'middle' period would be Guy Callendar's work on atmospheric CO2 levels primarily in the 40s and 50s. The 70s and 80s were indeed the END of the period of legitimate scientific debate over whether AGW was happening. No remotely rational scientist now disputes this... only the degree of warming we can expect is still in question, and even there the scientific grounding for 'skeptic' positions (e.g. 2 C or less from a doubling of CO2) is becoming incredibly thin. -
chris at 21:25 PM on 9 July 2010Hotties vs Frosties?
Baa Humbug at 20:47 PM on 9 July, 2010 Marcus: "Anyone who is being honest knows that, over a 15 year time period, global temperatures are subject to a very high noise to signal ratio. That doesn't mean that the planet hasn't warmed in that time". Baa Humbug: "Yes that's true Marcus. But it makes me wonder, how is it that in the early 90's we were so confident that AGW was happening that we set off on protocols like Kyoto? The pre 40's warming was said to be mostly natural, but the post late 70's early 80's warming was mostly anthropogenic. Hardly 15 years and subject to signal to noise ratio indeed." Marcus gave you the answer to that Baa Humbug in the very first sentence of the comments: "Here's the problem though John-*context*." It's what distinguishes science/knowledge from superstitution/"common sense". We already knew in the early 90's what we know a little better now, that carbon dioxide is a greenhouse gas, that it is a dominant contributor to the Earth's surface temperature, that increasing atmospheric concentrations will cause the Earth temperature to evolve towards a higher "equilibrium" temperature and so on. We don't have to "see" the earth temperature rising to know with a high degree of certainty that the Earth will warm as greenhouse concentrations rise, any more than we have to see atoms to know that these exist or to see DNA mutations in somatic cells to know that cigarettes greatly increase the risk of lung cancer...... -
Donald Lewis at 21:23 PM on 9 July 2010Hotties vs Frosties?
In my opinion, the difference between a frostie and a hottie is not about reflexes in looking at ambiguous data. It is about preconceptions which are prescientific. That is why "denial" is an appropriate term, in my view. The frosties rarely present all their assumptions. Perhaps they are unaware of them. In any case, in my view, they are driven to reject a wealth of evidence by internal arguments they may never voice. As a result they scramble to vocalize arguments saying the opposing view is not really established beyond (unreasonable) doubt. They want their preconceptions to survive the onslaught of data that seems to contradict their preconceptions. In my experience, the only way preconceptions can survive the onslaught of empirical data is through ones luck of preconception, or denial of the data. I would compare the theory of anthropogenic global warming to the theory of evolution. Where I live, the polls all indicate that the majority of the population does not believe in evolution. (The general population believes, instead, in an origin of species as the result of something compatible to what is described in the Bible.) When you ask educated folks, among the sub-population that denies evolution, about their view of evolution, they may provide a long list of "reasons" not to believe the science. None of those reasons will mention the bible. The reality is they think evolution contradicts the bible, so they know evolution didn't happen, so there must be a problem with the data and/or the researchers.) Instead one hears, the data is incomplete, two scientists disagree about details, Darwin was wrong about something, a duck isn't a dinosaur, ... whatever. The preconceptions bolstering climate change frosties are just more diverse and not yet well identified by the hotties. -
carrot eater at 21:14 PM on 9 July 2010Hotties vs Frosties?
Humbug, Kyoto was adopted in 1997, not the early 1990s. It did take some time in the beginning, before people became confident that warming was indeed definitely taking place. Hansen was confident there was warming in 1988, but you must note that he was examining the trends over the past *30* years, when he said that. He then somehow estimated the chance that the warming to that point could take place through natural fluctuations. And, finally confidence comes from having basic physics on your side; people were predicting warming well before it was obvious. Now, was everybody confident by 1988 like Hansen was? No. Not at all. People were cautious. But through the 90s and 2000s, it became more and more apparent. When finally it was found that the UAH satellite team's initial findings of no warming and then limited warming were in error, then there was really no room left. There simply was warming since the 1960s/1970s. But it's bizarre to say that you won't accept that warming is happening now, just because somebody else accepted it was happening by 1990 or 1997 and gave reasonable analysis to support their position.
Prev 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 Next
