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Ken Lambert at 09:01 AM on 4 May 2011How climate change deniers led me to set up Skeptical Science website
Tom Curtis #65 I have already invited everyone to the Flanner thread, where Tom Curtis has not responded to my latest piece, even though he has quoted numbers in detail above in #65. This gross bit I cannot let go elsewhere: "To cap the later of you then divided the result by two again apparently because the measured 2 million square kilometer reduction in sea ice did not fit your prejudice. Again, you have refused to acknowledge that that mistake was a mistake." I got that 'prejudice' from Dr Trenberth, Tom - Dr Trenberth says in his "Tracking the Earth's Energy" Aug09 paper: Quote "Sea ice is important where it forms. Record losses of Arctic sea ice of about 10^6 km2 occurred in summer of 2007 relative to the previous lowest year [25], although the thickness and volume of the ice is quite uncertain. To melt 10^6 km2 of ice 1 m thick and raise the temperature of the water by 10 degC requires 3.4 x 10^20 J, or globally 0.02 W/m2. For 2004–2008 this is about 0.9 x 10^20 J/yr." Endquote Am I to be allowed to answer the rest of Tom Curtis' post at #65? -
skywatcher at 08:16 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
So far as I can see though Chip, your calculation of error is a purely statistical construct from the modelled timeseries values (the RMSE of the series), rather than a physically-based estimation of the uncertainty, which might be generated in this case, say by comparing observed melt values with modelled melt values where the series overlap? I'm not saying it's necessarily an incorrect way of estimating uncertainty, but it is not similar to the IPCC example you refer to - as seen by the fact that your uncertainties appear constant, while in the example, they change (increase with age in that case). Please correct me if I am wrong! Your conclusion fundamentally depends on the uncertainties being large enough to encompass the recent values in 2007 (and of course should have included 2010). Your factual error, surely, is of course that 2010 is the greatest melt season, not 2007, which also means that the two largest melts occurred in the past four years. Any further thoughts on my comments regarding melt values in comparison to mass loss (calving, recently accelerated flow rates)? I feel your paper inadequately deals with that and this largely leads to the erroneous statements on sea level. And why would sea level rise have had to have jumped to 3mm p.a. in the 1960s to confirm an accelerated contribution from Greenland alone? You never talk of all the relative contributions to sea level (thermal expansion etc) so this statement is made without context and is seriously in error. -
Bibliovermis at 08:14 AM on 4 May 2011Why 450 ppm is not a safe target
For comparison, the global mean passed 350 ppm in 1988 and is currently at 391 ppm. NOAA/Earth System Research Laboratory: Global CO2 Data -
scaddenp at 08:03 AM on 4 May 2011Models are unreliable
"Isn't meltwater, meltwater," Volume matters. At end of glacial, you have large amount of ice to melt below the arctic circle. The issue of interest for now wrt to sealevel rates, is that rate of warming is far higher than exiting a glacial but amount of ice available to melt is far less. As to BP, look at the data yourself. As to role of meltwater - this is unsettled science. There is good evidence of disturbance to thermahaline cycle and ditto for solar forcing. What causes the disturbance, relationships and timing is not settled. If you are really interested, read Wally Broecker on the subject. Relevance to now? Well no solar forcing and no disturbance to thermahaline cycle detected as possible causes of warming. -
johnd at 07:08 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Chip Knappenberger at 05:39 AM, fear not being seen as dense. Far from it, your contributions have provided an unusual degree of clarity and logic. -
Chip Knappenberger at 06:30 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Chris@107, If I may join your conversation… I am not following your assertion that we are somehow unique in comparing an observed data value with reconstructed data values, and assessing whether or not they differ from one another by examining the error range that we determined about the reconstructed values. As a prominent example, I direct you to page 2 and 3 of the IPCC Third Assessment Report, particularly Figure 1b (I hope I am not falling for some sort of bait here). It shows a 1,000 year reconstruction of northern hemisphere temperatures along with the observed temperatures since 1861 and includes, among other statements, “The 95% confidence range in the annual data is represented by the grey region. These uncertainties increase in more distant times and are always much larger than in the instrumental record due to the use of relatively sparse proxy data. Nevertheless the rate and duration of the warming of the 20th century has been much greater than in any of the previous nine centuries. Similarly, it is likely that the 1990s have been the warmest decade and 1998 the warmest year of the millennium.” This figure, procedure and conclusion are similar in nature to ours. And as to our offending sentence in the abstract, I don’t think any portion of it has been firmly established to be factually in error. -Chip -
chris at 05:43 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Dikran Marsupial at 23:07 PM on 3 May, 2011 apols again Dikran - I seem to have failed in conveying I was being tongue in cheek! You said my response was a little pedantic in an early post and I was using the theme of pedantry in my conversation with you. Absolutely no offence intended. These issues can become over-serious, and it helps (me anyway) occasionally to relax by being a little light-hearted in these discussions however serious some of the dimensions are. In my opinion the sentence: ”The greatest melt extent over the last 2 1/4 centuries occurred in 2007; however, this value is not statistically significantly different from the reconstructed melt extent during 20 other melt seasons, primarily during 1923–1961.” shouldn't have been included in the abstract, since first it's factually erroneous, and second because it gives a spurious impression of a precision. The meaning of statistical significance in this case needs to be qualified, since it refers not to the question of whether Greenland melts now are different from melt rates then, but to whether Greenland melt rates now are different from a reconstructed model of melt rates then. So it’s got little meaning without consideration of the accuracy of the model of historical rates and the variance in the data in the reconstruction. These aren't well specified with respect to reality even if they are specified within the model. If this was a study in a medical journal (say) in which there are clear conventions in the description of statistical significance, then a single sentence statement in an abstract is appropriate. Maybe I haven't read enough papers but I've never seen a paleoreconstruction assess statistical signficance between contemporary empirical data and paleproxy data. I would insist that this sentence be either removed or made to better represent the findings; e.g.: “”The greatest melt extent over the last 2 1/4 centuries within our study period occurred in 2007, although the very recent 2010 melt exceeds that of 2007; these value are not statistically significantly different from the reconstructed melt extent during 20 other melt seasons, primarily during 1923–1961. However we emphasize that this analysis relates to a comparison of contemporary melt with a historical reconstruction having considerable uncertainty” But if there are good reasons not to assess statistical significance in differences between contemporary empirical data and historical reconstructions, then I don't see that FKM should be the groundbreakers here. But that's for an appropriate expert to assess... -
Chip Knappenberger at 05:39 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
logicman, Despite your handle, I am have trouble following you :^) Pat authored his own article at Cato, do you think I am serving as propagandist to spin it other than in a way he meant it? Perhaps I am not understanding your question. And, back to your comment #70, question 1. Comments have never been activated at World Climate Report, the latest piece is no exception. However, we’d be happy to entertain funding offers to hire someone to oversee that feature! And as to your second question, I am not sure I fully understand it. Wasn’t that topic covered in subsequent discussions in comments with Dikran, skywatcher, et al.? Sorry to be so dense. -Chip -
logicman at 05:25 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Chip "It should be clear from Pat's recent Cato piece that he is not particularly concerned that a sustained rapid acceleration in the rate of sea level rise is imminent." The ambiguity in that statement might allow a propagandist to write with some truth that Michaels, aware that a sustained rapid acceleration in the rate of sea level rise is imminent, is not concerned. Since I am not a propagandist, I will merely observe that in my opinion he should be concerned! Perhaps you did not see my comment #70? Can you respond please? -
KR at 05:15 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Chip Knappenberger - Thanks for coming by! -
Chip Knappenberger at 04:50 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
citizenschallenge, While I appreciate the courtesy, I am not a professor, so there is no need to address me as such, "Chip" works just fine! It should be clear from Pat's recent Cato piece that he is not particularly concerned that a sustained rapid acceleration in the rate of sea level rise is imminent. In that piece, and in several others in his 'Current Wisdom' series (some of which we link to here), he explains why, citing recent papers from the scientific literature. You are quite free to reach a different conclusion! -Chip -
citizenschallenge at 04:37 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Professor Knappenberger, I apology if that came across a bit strong ~ insulting wasn't my intention. I had just finished reading Pat Michaels’ take: "Sell Me Your Beach House, Please!" and was feeling a bit feisty. Also, I did not mean to imply I thought your study had no value. But it seems a small piece. Perhaps destined to become a historic benchmark as the trends blast free of the background noise. ... it just seems wrong to present a study such as KFM as though it were in a vacuum, as Michaels and others are clearly doing. -
johnd at 04:31 AM on 4 May 2011How climate change deniers led me to set up Skeptical Science website
JMurphy at 22:30 PM, I don't know what more I can say except, courtesy of your post, I read it here first. Is Monckton that important a figure to you that you are now actively recommending others should read certain sections of certain newspapers just to keep up with the latest news about him? I remain fascinated/bewildered by the close attention being paid to him by the regulars here. -
johnd at 04:17 AM on 4 May 2011Could global warming be caused by natural cycles?
JMurphy at 22:06 PM, I follow the JPN-FRCGC model predictions which is included amongst the range of predictions on page 27 of your linked site. Just remain aware that I referred specifically to the El-Nino Index value, not whether that value was moving in or out of the range considered neutral or not. I note that NOAA confirm on page 3 and elsewhere that as at May 2nd, La-Nina conditions are still in place. -
citizenschallenge at 04:11 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Professor Knappenberger, For the record I don't mean to be rude... and I'm a laymen so don't pretend to speak to scientific particulars. Instead, I'm looking at all of this from the bottom up* and seeing and hearing the silliness being fed to people which totally misrepresent our knowledge. And then I read that dripping contempt that's displayed throughout Pat Michael's essay and it is genuinely heart breaking and aggravating. {*four decades worth} ~ ~ ~ ~ ~ ~ ~ That above soundbite being: relax there is nothing to be concerned about and nothing should be done to change the business a usual plan. Instead we the people are forced to continue being distracted by this debate game, or as Pat Michael so elegantly put it over at his CATO blog "Current Wisdom": Please Sell Me Your Beach House: ~ ~ ~ ~ ~ ~ ~ "In a world of unbiased models and data, they should roughly be in balance." ~ ~ ~ ~ ~ ~ ~ Shouldn't the models and data be biased to the actually dynamics they are recording rather than a "balanced" media PR presentation? -
citizenschallenge at 03:20 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Chip Knappenberger at 02:34 AM on 4 May, 2011 KR@91 et al., You all keep saying that our paper is obsolete. But this seems a wee bit over the top (to say the least). ~ ~ ~ ~ ~ ~ ~ In light of THE ARCTIC AS A MESSENGER FOR GLOBAL PROCESSES – CLIMATE CHANGE AND POLLUTION ~ COPENHAGEN MAY 3-6 2011 see Press Release see Abstract Seems to me it has been steamrollered into an irrelevant example of massaging the message. Then leaving it out there to dangle for the “skeptical” echo-chamber to morph it into another “aluminum tubes into nuclear weapons” distortion, then blast the soundbite through their media machine. -
Chip Knappenberger at 03:16 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
@97, Thanks to the commentors and moderators for keeping the overall tone of the discussions very positive. It is much more enjoyable (and probably more instructive) to have discussions about things (even when we disagree) in such an environment. Thanks again! -Chip -
Chip Knappenberger at 03:05 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Guys (skywatcher, Dikran, et al.), We probably have labored over the point about contributions to the recent trend long enough, I am not sure we are making any headway. I previously have said that there exists a set of conditions for which my suggestion that natural variability may play some role in the recent trend is wrong. Just that from what I know now, I don’t think those conditions represent what was occurring. So as a parting thought about this, I offer up this excerpt from our paper where we talk about this topic:“It is worth noting that the satellite observations of Greenland’s total ice melt, which begin in the late 1970s, start during a time that is characterized by the lowest sustained extent of melt during the past century (Figure 2). Thus, the positive melt extent trend includes nearly equal contributions from the relatively high melt extents in recent years but also from the relatively low ice melt extent in the early years of the available satellite record. The large values of melt extent observed in recent years are much less unusual when compared against conditions typical of the early to mid 20th century, than when compared against conditions at the beginning the of the satellite record.”
Now we did not explicitly mention “natural variability” but we did talk about “relatively low melt extent” at the beginning of the satellite record and its contribution to the recent observed trend. I doubt that many people attribute the “relatively low melt extent” to increasing positive forcings from anthropogenic activity. Jason Box had a comment pertaining at least to the first sentence of this paragraph:line 221-223: a good point: “It is worth noting that the satellite observations of Greenland’s total ice melt, which begin in the late 1970s, start during a time that is characterized by the lowest sustained extent of melt during the past century (Figure 2).”
I just don’t think I am completely off base here, but, I suppose you all are free to think otherwise! -Chip -
skywatcher at 02:37 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
I should say that although I've asked a lot of fairly strong questions about this paper, I very much appreciate Chip's coming here and discussing it.Moderator Response: [Dikran Marsupial] Well said, I agree completely! -
skywatcher at 02:35 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Chip #88, Dikran's already answered your question I think, and his first paragraph in post #90 is the key point I think. You can't blindly attribute a statistical derivation of only one component of Greenland's sea level contribution to 'natural variability' without first examining all the forcings, notably the significant aerosol forcings of the 1960s to 1980s. Furthermore, you can't then suggest that Greenland is not contributing significantly to sea level rise without assessing the magnitude of Greenland's contribution, and the proportion of that which is due to melting, rather than calving. Would the changes in Greenland melt contribution have been detectable, let alone significant, in the 20th Century sea level curve? I cannot tell from your paper, as you do not appear to have quantitatively examined this. It would appear that changes in ice discharge/calving would be detectable (Rignot & Kanagaratnam 2006), but you make no quantitative assessment of the component that you have modelled (melt). Why did you state that sea level rise would have to have exceeded 3mm/year earlier this century before you would consider Greenland's effect on sea level rise to be other than 'modest'? There are many more components to sea level rise than Greenland's ice alone, as you can find out at this website! That last paragraph in FKM 2011 looks worse every time I read it. -
Chip Knappenberger at 02:34 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
KR@91 et al., You all keep saying that our paper is obsolete. But this seems a wee bit over the top (to say the least). Granted, incorporating the melt extent for the summer of 2010 into the methodology as described in our paper may have required a few minor tweaks to some of the wording (and a few specific numbers). But, by and large, as I have said many times, I strongly believe (although I have not done the analysis) that the changes would not have altered the general nature of our conclusions (as we explained to the JGR editor). -Chip Knappenberger -
Dikran Marsupial at 02:33 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Chip@93 Sure, but not being able to rule something out doesn't actually mean much and isn't support for a return towards the mean, because it ignores the fact that CO2 radiative forcing is positive and incresing (and arctic temperatures are rising as expected) and there will be an albedo feedback effect. Physics trumps statistics every time - I know that - I am a statistician. -
Chip Knappenberger at 02:21 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Dikran@92, I don't think I said anywhere that I expect a (much of a sustained) return towards the mean from current levels (not meaning 2010, per se, but rather, the current 10-yr or so average). Just that some of the return (from negative territory) towards the mean early in the satellite record could/should not be summarily ruled out as being a result of natural variability. -Chip -
Alexandre at 02:16 AM on 4 May 2011Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
Typing from my cell phone here. Please disregard the many typos above... -
Alexandre at 02:14 AM on 4 May 2011Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
Chris G I would not suggest to strongarm China. The US is a huge importer. It's in the position to demand efficiency standards, for example. This would affect the US consuption directly. Chinese consumers would end up having access to the same goods, and that woul eventually affect their overall efficiency as well. American an European standards tend to be copied elsewhere in the world overtime, so I do believe this kind of role model leadership would have a practical effectiveness. Our Brazilian automotive emission laws only happened because developed countries did it first, then our bureaucrats thaought it would be a good idea to adopt it too. Those restrictuions could maybe include emission standards for the manufacturer. Also if the US had a more aggressive reneweable energy research (like say Germany), the costs of these sources would drop more rapidly, stimulating the migration without so much cohersion. I don't think the influence of the US as a world leader should be underestimated, even if it's not as hegemonic as it was years ago. The American influence on this issue has been negative so far. I'm convinced an American positive influence would make a large difference. -
Dikran Marsupial at 01:55 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Chip@88 no, just that you need to consider all forcings in order to determine whether something is attributable to "natural variability". There is also the fact that a recovery in the 70s/80s that is attributable to "natural variability" isn't any reason to think that levels will return to the long term mean in the face of rising CO2 radiative forcing/albedo feedback. -
KR at 01:54 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Chip Knappenberger - You've presented a few reasons for not incorporating the 2010 data. However, given your paper's focus on surface melt (not considering other issues such as glacial speed/behavior and calving events, or the multiple tracks of evidence indicating greatly increased mass loss over the last decade), and the lack of the 2010 data, your paper was obsolete on publication date. At the very least the available 2010 data should have caused you to revise your summary and conclusions. Inclusion of other mass loss data should have reversed the conclusions entirely. Given these issues, I don't think the paper adds much to the science. I expect, given the track record, that it will be used to argue that "it's not happening", presented as up to date by (for example) the Cato Institute and others. But it's obsolete. -
Dikran Marsupial at 01:52 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Chip@85 Sure natural variability exists, but you can't attribute a change to natural variability until you have seen what can be explained by changes in forcings (all of them including e.g. aerosols). As a statistician, I am not greatly impressed by merely statistical evidence that something is not ruled out. I understand the limitations of quasi-Fisherian significance testing, and I know that failing to reject the null hypothesis actually means rather little (Fisher knew that as well). For a start, it can only mean there is no reason to rule it out based on that one statistic considered in isolation. But why should we look only at that statistic in isolation and ignore all of our knowledge of climate physics that points strongly against a recovery due to natural variability? It seems to me that you are over-interpreting the significance of your test. AFAICS, the only value in it is that it shows those who would claim that the recent decline is unprecedented perhaps need to qualify exactly what they mean by "unprecedented". It doesn't tell you anything about attribution. -
dana1981 at 01:47 AM on 4 May 2011Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
Ken #16 - instead of resorting to knee jerk alarmism, maybe try reading the post and links. When prices go up, the easy way to curb bills is to decrease consumption, by investing some of the carbon funds in energy efficiency programs. In fac that's exactly what the RGGI states are doing, as I discussed in "A Real-World Example of Carbon Pricing Benefits Outweighing Costs". They invested 52% of the funds from their cap and trade programs in energy efficiency. China plans to establish a carbon cap and trade system by 2015, by the way. It will be incredibly embarrasing if they beat the US to it. -
Chris G at 01:43 AM on 4 May 2011Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
Of course, neither the US nor China want to put their economy at a competitive disadvantage; so, China wants to focus on per capita reductions and the US, it is not clear to me what the US officials want to focus on. But, we have one of the higher per capita emission levels, especially when you consider the cumulative totals; so, our leaders tend not to like China's proposals. Political backlash is a problem in a democracy. If the elected officials make an agreement that puts what the average person sees as a competitor on a level playing field, those officials are likely to lose the next election and have their agreement tossed out. Maybe the US debt to China can be leveraged to enforce an agreement, a calling of the debt if the US fails to comply. That would not save the officials, but it might save the agreement. I don't know; politics is not my strong point. -
mspelto at 01:38 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
I agree that the early to mid 20th century period of warmth did not lead to a substantial increase in volume loss for the GIS. However, the conclusion that are current period of warmth will not, is already wrong. There are too many different studies using different techniques that have shown the volume losses of GIS have increased dramatically in the last decade. That is what marks the current period as different. When I first worked on GIS glaciers most were in essential equilibrium, such as our main focus the Jakobshavn. Today the list of glaciers that have had substantial volume losses is long and covers many types of glaciers from calving to grounded termini glaciers as we noted in a, previous post at SkepticalScience. This includes Humboldt Glacier the glacier with the longest calving front. Not only are there volume losses but there have been some fundamental changes in glacier behavior that would have been observed if they had occurred in the mid-century period of warmer conditions. The proof that the current warming is generating more melting is in the response of the glaciers. -
Chip Knappenberger at 01:33 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
skywatcher@87, Perhaps I am missing something here. You and Dikran are suggesting that the negative melt anomalies in the late 70s/early 80s are the result of positive anthropogenic climate forcings? Or that they are not really negative anomalies, but rather represent the mean climate state at the time? Or perhaps even that the natural state was trending downward and then anthropogenic positive forcing stopped that downward trend and turned it positive? I guess all of these things are possibilities that would invalidate my conclusion. It is just, that in my opinion, I don't ascribe to any of them...but, admittedly, I could be wrong. -Chip -
skywatcher at 01:20 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
In addition to Dikran's point, #84, the appeal to 'naural variability' does not stand up. There has to be a process driving that change - presumably you (FKM) envisage that process reversing? What forced the variability, and why would melt be at all likely to return to some 'natural' base level given the well-understood climatic forcings in place at present? -
Rob Honeycutt at 01:19 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Chip @ 58... Your response is not very compelling to me for a couple of reasons. First, on an interpersonal level you're not responding to what I'm saying. You're merely speaking "at" me, not to me, and reposting things that I've already read. Second, your case is still not compelling, and is fact extremely concerning, in that you're essentially abdicating responsibility to get the research right. On one hand you're saying, "We didn't do the actual research" and then you're contradicting statements from one of the key people who DOES do the actual research. And those statements (from Dr Box) have been, obviously, quite forceful in their condemnation of the conclusions of FKM2011. -
Chip Knappenberger at 01:15 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Dikran@84, I was referring to a return from the negative ice melt anomalies in the late 1970s/early 1980s. With or without anthopogenic forcing, natural variability still exists, and since there is the possibility that positive climate forcings from human activities is not what led to the negative ice melt anomalies in the late 70s/early 80s, then a non-anthopogenic-induced return from those anomalies should not be out of the question. Right? -Chip -
Dikran Marsupial at 01:04 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Chip Knappenberger@82 There was signficant anthropogenic influence on the greenhouse effect in place in the late 1970s and early 80s (and decreasing negative forcing due to aerosols) so to use that as evidence that without positive forcing from AGW a return to the long term mean is a non-sequitur. Perhaps there is something missing from your post? There is no reason to expect a return to the long term mean according to mainstream climate science, which includes the CO2 being a greenhouse gas, climate sensitivity being of the order of a couple of degrees C per doubling and albedo feedback. All three of those suggest a return to the long term mean is unlikely. -
Alexandre at 01:03 AM on 4 May 2011Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
Sphaerica at 00:17 AM on 4 May, 2011 I have noticed this "alarmism against mitigation" for some time now. Dan Moutal mentioned an interesting similar pattern by the time of the CFC problem: people claimed that prices of apliances would skyrocket, poor countries would be denied access to these conveniences, manufacturers would go bankrupt, and so on. Of course, the world survived the Montreal protocol quite well. -
Chris G at 00:59 AM on 4 May 2011Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
Bern, Alexandre, Absolutely, it is a simple concept at the highest level; it is more complicated as you get into the details. I concur on everything you said, FF industry, US indebtedness to China, US in historical view (nevermind when the world's hungry turn their baneful eyes from their own leaders to the US), etc. IMHO, it would be foolish for the US to try to strong-arm China. It is to be hoped that we have a rational leadership when talks resume. No, I would guess that China is not interested in a carbon tax. A tax is how governments steer a free market, and China's market is not as free as the US's. Any agreement would have to focus more on emissions reductions rather than the mechanism for how those reductions were achieved. Pity that CO2 satellite did not make it in to orbit. My main point is that, despite the rather un-democratic nature of it, it might be more effective to pursue an emissions agreement amongst the top few economies rather than pursue one that is acceptable to 100 or more at the start. At this point, I, personally, would accept a non-democratic solution over no solution. -
Chip Knappenberger at 00:57 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
The Skeptical Chymist, I am not sure that you have it quite right when it comes to our statistical tests. There are 20 years during our reconstructed period (1784-1978) in which the observed melt index for 2007 was contained within the 95% confidence bounds about the reconstructed value. So our “test” was on individual years, not a particular period. If this explanation doesn’t answer your question, then perhaps I am not understanding it correctly. As far as whether or not the current melt extent and trend are important or not, our point was that there seems to have been another extended period of positive melt anomalies across Greenland for several decades in the early/mid 20th century, and that period did not result in a large uptick in the rate of sea level rise (although there is some evidence that the rate of sea level rise did increase a bit during that period). This led us to conclude that if the current melt extent stayed somewhat equivalent to what it was back then, we wouldn’t expect a big jump in the rate of sea level rise as a result of cryospheric processes (surface melting and dynamic ice loss from glaciers). Clearly, if the melt (and other losses) where greater than back then, then so too will be the contribution from Greenland. 2007 and 2010 were years with a lot of melt. 2008 and 2009 were not. -Chip Knappenberger -
michael sweet at 00:54 AM on 4 May 2011Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
Ken, For only the most simple example: If energy costs go up 50% and I install more insulation so that my energy use goes down 60% I save money and have lower total bills. Your suggestion of bankruptcy is alarmism of the worst kind and is easily shown to be untrue. If I install a ground source heat pump I save money, even if energy costs go way up, and it expands the economy since I have to pay to have the heat pump manufactured installed. -
Chip Knappenberger at 00:37 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Several commentors here seem to have taken issue with the idea that some of the positive trend in ice melt observed across Greenland from 1979-2010 could potentially have resulted from natural variability. The reason the results of our paper suggests this, to me at least, is that the ice melt in late 1970s and early 1980s (i.e. the early years of the satellite record) was considerably below the long-term average (or at least as we have reconstructed it). So, even without any positive forcing from a greenhouse effect being enhanced by anthropogenic influences, a return to the long-term mean (at some point) would seem a reasonable expectation. I doubt that the entirety of the trend in ice melt extent across Greenland from 1979-2010 results from natural variability, but it would seem a bit foolish to rule out the possibility of any contribution whatsoever, based upon our results. So, to me, the contribution is probably greater that zero and less than a 100%--so I am comfortable with my characterization that a “sizeable” portion “could potentially” be a result of natural variability. -Chip Knappenberger -
pbjamm at 00:35 AM on 4 May 2011How climate change deniers led me to set up Skeptical Science website
Albatross@54 I think that comments regarding the quality (or lack thereof) of other climate blogs are relevant and on topic for this thread. I became a regular (lurker) here because of SkS' quality of science and dialog when compared to places like WUWT. Ken Lambert@everywhere Please stop trying to derail this thread and take the discussion back where it belongs. -
The Skeptical Chymist at 00:24 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Barry@77 Yes it is perfectly acceptable for a reviewer to submit a rebuttal of a paper which they reviewed but which they consider has major flaws. From reading Dr Box's blog it appears he is doing so. Regarding the authors statement that "one more year of data is not going to materially affect our analysis or conclusions" I agree with Albatross@61. The last few lines of a papers' abstract is where you put your "take home" message/ most important conclusions. It is very clear that including 2010 data would have required a rewrite to this section, because it would have altered their "take home" message. To state otherwise, as Chip and Co did, is simply incorrect. Otherwise if Chip@58 is still around I have a question or two as my uni (oddly enough) doesn't have an online subscription to JGR. 1) You tested whether the melt in 07 was sig diff to the melt between 1923-1961. Why did you test against 20 specific years, instead of the whole high melt period? 2) Why does your paper emphasis the duration of the historical high melt period vs present melting? Given that temperature increases in Greenland (and hence melting) are only just getting started, wouldn't the magnitude of the melting and trend of melting be more important? Or to rephrase, the current high melt is almost certain to last for longer than the previous, why is the fact that is hasn't (yet) particularly important? -
JMurphy at 00:21 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
skywatcher wrote : "Aside from that, I feel Dr Box should have conducted the second review, and insisted on paper rejection as the changes had not been made. Had he done that, and the paper still been accepted, he would have a stronger case. But having not done that, he was not in a good position to cry foul that the paper got through." I'm not so sure about that - remember the kerfuffle over O'Donnellgate, with regard to the Antarctic ? It seems that there would be an outcry no matter where in the chain these criticisms are made, and if a paper is refused publication because of the involvment of someone whom the so-called skeptics could claim was censoring 'opposing' views...well, that would unleash a great wailing and gnashing of teeth in the Denialosphere ! -
Bob Lacatena at 00:17 AM on 4 May 2011Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
16, Ken,Bankrupcy??
This is alarmism of the worst kind, and the crux of the problem with those who fiercely resist the science and the solutions. This panicked fear that costs must be extreme, to the point of destroying economies, is absurd. First, no one is very easily going to give up comforts, let alone necessities. No one is going to sit idly by while all of civilization crumbles. That only happens when the economy spirals out of control through greed and mismanagement (see 1929, 1987, 2007). Second, a transition to alternate energy sources does not represent a net loss to society as a whole. The infrastructure of society is constantly being renewed. Nothing lasts. Manufacturing and transportation equipment, roads, rail lines, power lines, power plants, everything is constantly being maintained or replaced. So if we simply change what we use to replace the old... newer, better techniques using renewable energy sources rather than fossil fuels... there is no net loss to the economy. The loss is only to those who would profit from purely fossil fuel solutions. In the long run, there is a net gain for society. All economies benefit. In fact, the only losers will be those who desperately cling to the old, inefficient and uneconomical ways, as the smarter, more adaptable economies move forward and embrace change. Alarmism and panic are not helpful. -
Tom Curtis at 00:13 AM on 4 May 2011How climate change deniers led me to set up Skeptical Science website
Ken Lambert @64, while you have not made any significant errors of calculation, you have persistently made conceptual errors which if left uncorrected would result in errors in the final result of up to two orders of magnitude. You are equally persistent in never acknowledging these errors as errors, not matter how glaringly obvious they may be. Of these, my favourite examples are your rather arbitrary decision that the incoming flux for 90 days must really be the incoming flux for (approx) 10950 days, a view you returned to repeatedly and have never acknowledged as a mistake; and your decision that the average incoming flux over a 90 day period was the peak incoming flux over that period, and that consequently it needed to be divided by two to find the average. To cap the later of you then divided the result by two again apparently because the measured 2 million square kilometer reduction in sea ice did not fit your prejudice. Again, you have refused to acknowledge that that mistake was a mistake. All of this is of a piece with the original basis of discussion, your insistence that the low altitude of the sun in the arctic summer must raise ocean albedo so much that any calculation showing a strong positive feedback from loss of arctic sea ice can be rejected out of hand. In arguing for this, you never calculated the relevant values, but merely insisted the work of a number of scientists who had was flawed. Apparently the effect was so obvious it did not need calculation, and the scientists so stupid that they had missed it entirely in their calculations. The belief that you can rebut the scientists without making the calculations makes no sense without those two assumptions. I attempted to supply the calculations for you - making sure to bias the results in favour of your arguments. Unfortunately I made a number of trivial errors which needed to be tracked down and corrected. Now that they have been tracked down and corrected, they clearly show your original assumptions about the magnitude of the effect where mistaken. Rather than acknowledge your error, you have launched a major attempt to disrupt this thread - and changed the subject on the Flanner thread. You have certainly not, or course, acknowledged your error. I have resisted pandering to your attempts to derail this thread until now. Rather, I responded on the appropriate thread. Rather than filling this thread up with your false claims, perhaps you also can keep the discussion where it belongs. -
skywatcher at 00:03 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Seems to me there are several issues that come out - 1: statistical significance of the recent years in relation to past years according to the model. Whether or not they are technically correct is actually less of an issue than their avoidance of the modern trajectory of change. It's quite disingenuous to talk of that trajectory earlier in the paper, yet leave it out of the conclusions. 2: Avoidance of the issue of mass loss versus surface melt - mass loss includes ice loss through calving, which has accelerated since the mid-20th Century. Surface melt is not necessarily therefore a good proxy for sea level rise resulting from Greenland. Both the above points allow two of the authors, as noted by others above, to falsely suggests that 'there's nothing to see here' in Greenland, despite all the evidence of accelerating mass loss described by Daniel Bailey. 3: The review process. I have to say I agree with barry here - I don't like the airing of private reviewer comments such as has happened here. That does not seem to me to be good academic discourse. Aside from that, I feel Dr Box should have conducted the second review, and insisted on paper rejection as the changes had not been made. Had he done that, and the paper still been accepted, he would have a stronger case. But having not done that, he was not in a good position to cry foul that the paper got through. That the other (anonymous) reviewer gave the paper a free pass as far as can be seen, is perhaps more of an issue, but the natural process of academic discourse should be allowed to progress - ie that relevant academics submit responses critiquing the paper. Given how (deliberately) poorly-written the conclusions are, and that it is already out-of-date, I suspect this will happen. -
Ken Lambert at 23:30 PM on 3 May 2011Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
"It's important to distinguish between prices and bills – an increase in the former doesn't necessarily cause an increase in the latter, if other measures are taken to prevent bills from rising." And in a competitive economy what measures would those be? Bankrupcy?? -
KR at 23:14 PM on 3 May 2011Waste heat vs greenhouse warming
RSVP - I considered providing a detailed response to your last posting. The thing is, I would just be repeating what I and other posters have said, over and over and ... (repeat as desired). I believe, instead, that I'll just leave that as a coda to this discussion. You've consistently displayed what I consider a cardinal sin of intellect - You have failed to learn in the face of obvious errors in your thinking. You're locked into your opinion, come Hades or high water. Your opinion holds proof against both quantitative and qualitative evidence to the contrary. There's nothing I can do about that - a rational discussion seems impossible. I believe readers can peruse this thread and come to their own conclusions based on what has been presented. Finis. -
Dikran Marsupial at 23:07 PM on 3 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
chris@79 Until I got to the bit that said "I have a feeling you are arguing for the sake of it somewhat (or seeing who can raise pedantry to its most extreme level - you might be inching ahead now!).", I was going to reply to your post, but I see little point if you can't conduct a scientific discussion in a civil manner. Especially after calling my interpretation of the review "silly" because I based in on words Box had actually used. No, I haven't been engaging in pedantry, merely stating my opinion on Box's review and correcting a few errors in your responses. As it happens the statement that you object to in the abstract, seems fine to me. Yes, it is uninteresting, but I am in favour of papers that place bounds on the strength of conclusions that can be drawn. Unless you can identify a methodological flaw in the statistical test that supports that statement, then there is nothing wrong with it. Unless you can behave in a more scientific manner, that is the end of the discussion for me. P.S. No problem about the "Dikram", it is not my real name anyway.
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