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trunkmonkey at 14:32 PM on 4 May 2011Models are unreliable
363. We established a while back that we know nothing at a decadal scale because the models can't resolve the irregular and powerful influenses of the ocean sloshings; ENSO, PDO, AMO, IOD (It's almost like Lake Tahoe must have a dipole as well). These influences are stronger than the expected warming so we could concievably have a decade of cooling or a decade of warming much greater than the models predict and it would mean nothing (except politically). The implication of DO/meltwater is profound, because if it is internally driven, we might not know anytinig at a centennial or millenial scale either. -
Albatross at 12:33 PM on 4 May 2011How climate change deniers led me to set up Skeptical Science website
Ken @71, "I have already done that at #64" And yet before your comment #71 and after #64 you managed to make two more off topic posts at #68 and #70 :) Now, please either speak to the content of John's post/article, or move on. Thank you so very much. -
Albatross at 12:13 PM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Hello Chip, Regarding your claim that "My [Chip's] command of English must be slipping,". Perhaps it is. Let me help if I may. And for the record you never have provided an explanation or specific reply to my comment original comment @61, so it is not possible for me to not "like" your explanation. Below is my post at 61 repeated here for everyone's convenience. I spelled out the problem with your claim very clearly: "You claimed in your response that: "We would like to note that waiting for one more year of data is not going to materially affect our analysis or conclusions." We know that claim in demonstrably false, because the melt data for 2010 surpassed those for 2007, which renders the following from your abstract obsolete (i.e., including those 2010 would have very much have affected your conclusions): "The melt extent observed in 2007 in particular was the greatest on record according to several satellite-derived records of total Greenland melt extent." Including those 2010 data also renders the first part of this conclusion in your abstract obsolete, while also calling into question the validity of the second part of the following: "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" So contrary to your claims made here and elsewhere, the 2010 do very much affect your conclusions and desired narrative. " To summarize (again), the greatest melt over the last 2 1/4 centuries was in fact in 2010, not 2007. You claim that excluding those 2010 data "is not going to materially affect our analysis or conclusions" is demonstrably false, unless you are trying to argue that the 2010 figure was not higher than that observed in 2007. Thank you. -
Chip Knappenberger at 11:56 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Albatross, My command of English must be slipping, because upon re-reading your comment 61 I see nothing that I haven't already addressed. Just because you, perhaps, didn't like my explanation doesn't mean that I haven't offered one. -Chip -
Albatross at 11:44 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Hi Chip, No, #112 does not address the issue, and your post @115 simply evaded the issue. Please read my comment @61 again-- I provided a link to that comment for your convenience in my post at @114 above. I was very specific in that post, concerning the claim that you made @ 58 and why is was demonstrably false. Thank you. -
muoncounter at 11:38 AM on 4 May 2011Why 450 ppm is not a safe target
dorlomin#2: "methane in the atmosphere exceeds 2ppm." Shakova and Semiletov 2007 reports: the surface layer of shelf water was supersaturated up to 2500% relative to the present average atmospheric methane content of 1.85 ppm, pointing to the rivers as a strong source of dissolved methane -- emphasis added That's consistent with the graph shown below: source
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Chip Knappenberger at 11:30 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Hi Albatross, I think I discussed the general topic you were interested in at #61 regarding the impact of 2010 (which remains unknown), in my comments posted above at #112. If not, maybe you can ask them again. Thanks, -Chip -
Marcus at 11:10 AM on 4 May 2011Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
"And in a competitive economy what measures would those be? Bankruptcy??" Of course, this is a text book argument from the Contrarian Movement. As has already been pointed out, the additional cost of carbon-rich energy, when taxed, will be applied to the *unit* cost of the energy (in MJ or kw-h), not to the total bill. In the last 10 years, I've seen my electricity tariffs rise by 8c/kw-h (due almost entirely to privatization & inflation), yet I'm currently paying about $40 per month *less*-on my total electricity bill-than what I was 10 years ago, simply by halving my daily use (purchasing energy efficient appliances & light globes, less reliance on stand-by modes & swapping my electric hot water system for a continuous flow gas hot water system). Now it's true that I spend about $20/month for my gas hot water, but that still leaves me $20/month better off than 10 years ago-& I can probably improve my position further by getting insulation installed to reduce my energy use for heating & cooling-so claims that reducing our CO2 emissions will send us *bankrupt* are just complete nonsense. Businesses & Industry also have plenty of room for reducing their CO2 emissions *and* reducing their total energy use. For example, the cement industry generates about 1t of CO2 for every tonne of cement made. Now I've seen evidence to suggest that this can be significantly reduced by measures like (a) recycling of old cement, (b) use of aluminium silicate instead of Calcium Carbonate, (c) capturing the CO2 from baking Calcium Carbonate & converting it to algal biomass, (d) using bio-gas, rather than natural gas, to bake the calcium carbonate. Of course, if the industry also captured its waste heat & converted it to electricity, then they could offset the costs of a carbon tax via the sale of electricity (co-generation). So we see that, yet again, a Carbon Tax represents an *opportunity*, more than it does a *burden*. -
Albatross at 11:09 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Hello Chip, Back at #61, I showed that you made a demonstrably false statement/claim in you post @58. I was wondering whether or not you have any thoughts on that matter? I also have some other comments/questions, but have to take care of some other matters right now. -
Bern at 10:47 AM on 4 May 2011Why 450 ppm is not a safe target
mandas: Aim high and underachieve, rather than aim low and underachieve by even more. -
mandas at 10:30 AM on 4 May 2011Why 450 ppm is not a safe target
I both agree and disagree with your position re the target of 450 ppm. I agree that it is dangerous, and that the effect on the environment are likely to be significant. However, I disagree that it should not be an aspirational target, because given the current state of politics and the pitiful efforts to reduce current emissions, 450 ppm is likely to be at the low end of what we can realistically achieve. I am very concerned by this, and I despair about what the state of the environment is going to be at the end of this century because of it. But what can you do? -
Chip Knappenberger at 09:40 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Tom@111, Thanks for the questions. Our ice melt index is an average of the ice melt extent reported by three different research teams (using different methodologies) studying ice melt across Greenland. We didn’t feel that we were in a position to pass judgment on which of the methods was better, so we took the data provided us by the researchers, standardized it, and averaged the three standardized values together for each year. That is why we refer to our value as an ice melt extent “index” (it is unitless). So, the zero value of our index is really just close to the average of the index for the period 1979-2009. Regarding calving, see my comment @112, I think it will answer your question. And regarding the relationship between our reconstructed ice melt index and Greenland temperatures, remember that we also incorporate winter NAO along with summer temperatures into our reconstruction model. NAO doesn’t have a large effect, but it does has some effect, and its influence likely explains the situation that you describe. I hope this helps! -Chip -
Ken Lambert at 09:39 AM on 4 May 2011How climate change deniers led me to set up Skeptical Science website
pbjamm #66 "Ken Lambert@everywhere Please stop trying to derail this thread and take the discussion back where it belongs." I have already done that at #64 - come on over to the Flanner thread yourself. -
RW1 at 09:37 AM on 4 May 2011An Even Cloudier Outlook for Low Climate Sensitivity
KR, "RW1 - Looks like both SW and LW; see the bottom of column 1, page 1524, where Dessler 2010 discusses combining the uncertainties of SW and LW measurements to determine total uncertainties." Yes, I know about that. That would seem to indicate it is the net SW and LW flux, but I should probably clarify this with Dessler himself just to be sure. -
Ken Lambert at 09:37 AM on 4 May 2011How climate change deniers led me to set up Skeptical Science website
#69 Tom Curtis Dr Trenberth is estimating the 'annual' contribution of Sea Ice loss in the Arctic to the global energy imbalance budget. If you want to look at the Sea Ice loss relative to 1979, you need to look at the 'cumulative' loss over 32 years. -
Chip Knappenberger at 09:28 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
skywatcher@110, Thanks for the good questions. Let me try to answer them. You are correct that our uncertainty bounds represent statistical uncertainty in our model (which has some contribution from measurement error in that the model was built from likely non-perfect observations). So, the better the model performs, the tighter the error bounds. Or another way, if you prefer, the worse our model is, the wider the error bars and voila, nothing is statistically different than anything else (I would imagine that this is a property shared by most statistical models). All I can say, is that we tried to produce the best model that we could and reported the statistics associated with it. I believe this is the same thing as was done in the study I referred to that the IPCC highlighted. We did not report the error bars associated with our observed melt index, nor did we consider them in our determination of whether 2007 was or was not statistically different from any of our reconstructed values (including error bars). If we had considered errors in our observed melt index, I imagine that the number of reconstructed values which were not found to be statistically different from 2007 would have increased. And, just as in the example I pointed out from the IPCC, our error bars do indeed increase as predictor variables drop out as we go back in time. This is clearly stated in our paper, where we stated “It should be noted that the confidence of the reconstruction, as indicated by the error bars in Figure 2, degrades in the period prior to 1840 as the amount of independent data is reduced.” As far as 2010 having a greater melt index value when processed through the methodology described in our paper, I have not done the calculation, so I don’t know. I have reasons to believe it is not as cut and dry a situation that many of you all tend to want to make it. Further, I don’t see it as a factual error. If the sentence that everyone has the most concerns about is placed back into its proper context of the abstract, it should be plainly clear that our period of record, and thus the sentence in question, only goes through 2009. Heck, the title of our paper is “A reconstruction of annual Greenland ice melt extent, 1784–2009.” So I don’t think that anyone who reads the title and/or the abstract thinks that we have secretly left out 2010. If you picked our paper up in the year 2025 and started reading it, I don’t think you would be under the impression that this sentence in the abstract “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” was referring to the period 1800-2025. So there is not a factual error in that sentence as written in context, nor has it been established that 2010 has a greater melt index (using our methodology) than 2007. But, like we said in our paper, “…preliminary estimates place the ice melt of 2010 at their highest level since at least 1958” so the possibility exists that 2010 may exceed 2007 (but even so, it doesn’t effect the correctness of that sentence in our abstract in context). Regarding calving…our paper was about surface ice melt, so our comments on other dynamic changes were mere speculation under the assumption that surface melt and other dynamic processes were correlated. As we stated in the paper “The forces acting in concert with ice melt across Greenland to produce higher global sea levels currently, should also have been acting during the extended high‐melt conditions from the mid‐1920s to the early 1960s.” If this assumption is invalid, or is becoming invalid, then our suppositions following there from may need reassessment. I hope this helps explain where we were coming from. -Chip -
dorlomin at 09:22 AM on 4 May 2011Why 450 ppm is not a safe target
Are you sure about this? "In parts of the East Siberian Arctic, methane in the atmosphere exceeds 2ppm. This is partly responsible for temperatures in the Arctic rising 2-3 times faster than in the tropics" The Zepplin station in Svalbard shows a slight decline in YOY methane concentrations. http://www.esrl.noaa.gov/gmd/dv/iadv/graph.php?code=ZEP&program=ccgg&type=ts I would have thought Arctic amplification is far more likely to be down to factors such as increased water vapor in the air, changes in ice albedo than methane. -
Tom Curtis at 09:10 AM on 4 May 2011How climate change deniers led me to set up Skeptical Science website
Ken Lambert @68, so you don't see using the previous lowest year to 2007 as the benchmark when the discussion regards net increase in incoming flux relative to 1979 as an error? -
Tom Curtis at 09:07 AM on 4 May 2011Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
Chip Knappenberger, I am having difficulty coming to grips with your paper, in large part because I am unable to access the original (given my limited means). I would appreciate it if you would answer some questions for me. With regard to the Ice Melt Extent Index in your paper, does the zero value represent total ice melt equaling total snow accumulation such that for negative values, the GIS gains mass if we ignore glacial calving, and positive values a mass loss? If not, what value does represent an equality of mass gain and loss (ignoring calving)? Further, although your paper does not deal with glacial calving, do you think it is reasonable to treat the Ice Melt Index as a proxy for total mass loss from the GIS as Michaels is doing, and as you appear to to do here. Finally, your Ice Melt Index shows similar values in the periods 1840-1920 and 1960-1990 even though Greenland temperatures where apparently half a degree colder in the former period. Is there any particular reason for this? -
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.
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