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Comments 54601 to 54650:

  1. Bostjan Kovacec at 23:10 PM on 3 September 2012
    Realistically What Might the Future Climate Look Like?
    @Tom 51 I can agree with your argument that it's human volcanoes that keep us nice and cool, and yes, who knows when – if ever - people will stop burning coal and oil. You're right also that Shellnhuber did say that it's Ramanathan who says we've already committed to 2.4 oC and he did say there are uncertainties about that. 2.1, 1.9, or even »just« 1.7 – that's really not that important. Now, I've listened to Ramanathan's lecture and it makes enough sense to be skeptical about the »budget«. With so many lives at stake I believe we have to take Ramanthan’s message seriously until he’s proven absolutely wrong and not vice versa. What worries me it's that small detail about the atmospheric lifetime of the GHG and aerosols. If humanity happened to achieve emission reductions as in Figure 1 (red curve seems more »plausible« to me), than we could expect a sharp drop in aerosols and a huge acceleration of warming. We saw that in the nineties here in Europe and I experienced it in my home town. When people started heating homes with gas and the Balkan wars destroyed most of the industry the sky became blue again and temperature skyrocketed. We would’ve cooked already if it wasn’t for a local factory which took care of us by spewing tones of TiO2 up the air every day. My local summer Tm from 1851 to 2012. Horizontal line marks 1988 when local industry collapsed. 2003 spike is clearly visible – that’ll be just an average summer by 2030s according to UK MetOffice. I really wouldn’t want to be offensive to anyone, but in this light, I find talking about the “budget” – and not mentioning any uncertainties associated with it - just music to Ms Merkel’s (and everyoneelse’s) ears. In the end we’ll happily accept sulfuric acid/TiO2 air-conditioning. Nobody will remember those “uncertainties” in calculations. The most important thing is that it’ll be good for GDP and everyone will be happy. So I’d suggest a short disclaimer for figure 1: “with massive GE effort”.
    Moderator Response: [RH] Fixed image width that was breaking page format.
  2. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    Tom, I have worked on public surveys (on Tobacco use) and when we analyzed the data we only deleted responses that contradicted themselves. It is very difficult to set up an objective measure to reject samples. You might be surprised how dogmatic some deniers are. Read the comments on WUWT for examples. People who believe in conspiracy theories often believe in a lot of theories. Lewandowsky has data he has collected. If you do not like his data you are welcome to perform a better survey and publish your results. If the consensus of scientists is that the data are not supportable than this paper will not be cited by anyone else. That is how science is normally done. I strongly doubt that mainstream scientists will continually cite this paper if the methodology is questioned. It is the deniers who cite papers that have been shown to be poor, since they have no good data to support their premises. I am interested in surveying High School students on Global Warming for publication. Albatross: do you do public surveys for publication?
  3. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    Have completly missed this hot topic! But it is nice to note that genuine skepticism is resulting in deeper analysis, which can only be good. It's better than all the fawning that goes on in the 'other' camp.
  4. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    I would just like to second Geoff Chamber's comment and thank Tom Curtis for his honest and intellectually rigorous analysis of Stephan Lewandowsky's paper. I hope Stephan will follow his sound advice and rewrite or withdraw this seriously flawed work.
  5. Realistically What Might the Future Climate Look Like?
    I wold like to remind everyone here that the terms "catastrophy", "catastrophic", etc. already contain a value judgement. While most people coming to these pages are likely sharing similar values and are thus concerned about GW, many others are not, or not yet, as they do not share those values. While the denier community mocks the "C", the scientific community shies away from c-words as it is supposed to stay neutral on such judgements. Thus, leadership will have to come from others. As Bostjan pointed out, it will not come from politicians, as they want to be reelected, and not from the grass roots. That leaves NGOs, the media, and prominent individuals (such as Al Gore I guess). Thanks to SkS, they can find most of what they need here.
  6. Models are unreliable
    opd68 @554, no, there is not a universally accepted measure of Global Mean Surface Temperature (GMST) accepted by all sides. HadCRUT3 and now HadCRUT4, NCDC, and Gistemp are all accepted as being approximately accurate by climate scientists in general with a few very specific exceptions. In general, any theory that is not falsified by any one of these four has not been falsified within the limits of available evidence. In contrast, any theory falsified by all four has been falsified. The few exceptions (and they are very few within climate science) are all very determined AGW "skeptics". They tend to insist that the satellite record is more accurate than the surface record because adjustments are required to develop the surface record (as if no adjustments where required to develop the satellite record /sarc). So far as I can determine, the mere fact of adjustments is sufficient to prove the adjustments are invalid, in their mind. In contrast, in their mind the (particularly) UAH satellite record is always considered accurate. Even though it has gone through many revisions to correct for detected error, at any given time these skeptics are confident that the current version of UAH is entirely accurate, and proves the surface record to be fundamentally flawed. They are, as saying goes, always certain, but often wrong.
  7. Dikran Marsupial at 21:08 PM on 3 September 2012
    Models are unreliable
    opd68 Rather than validate against a single dataset it is better to compare with a range of datasets as this helps to account for the uncertainty in estimating the actual global mean temperature (i.e. none of the products are the gold standard, the differences between them generally reflect genuine uncertainties or differences in scientific opinion in the way the direct observations should be adjusted to cater for known biases and averaged).
  8. Models are unreliable
    My initial comment on here and firstly thanks to the site for a well-moderated and open forum. I am a hydrologist (Engineering and Science degrees) with a corresponding professional interest in understanding the basics (in comparison to GCMs, etc) of climate and potential changes therein. My main area of work is in the strategic planning of water supply for urban centres and understanding risk in terms of security of supply, scheduled augmentation and drought response. I have also spent the past 20 years developing both my scientific understanding of the hydrologic cycle as well as modelling techniques that appropriately capture that understanding and underpinning science. Having come in late on this post I have a series of key questions that I need to place some boundaries and clarity on the subject. But I'll limit myself to the first and (in my mind) most important. A fundamental question in all this debate is whether global mean temperature is increasing. This has meant we need some form of predictive model in which we have sufficient confidence to simulate temperature changes over tim, under changing conditions, to an appropriate level of uncertainty. So, my first question that I'd appreciate some feedback from Posters is: Q: Is there a commonly accepted (from all sides of the debate) dataset or datasets that the predictive models are being calibrated/validated against? Also happy to be corrected on any specific terminology (e.g. GMT).
  9. Arctic Sea Ice Extent: We're gonna need a bigger graph
    Thanks, Andy. Reposted it to the SkS FB page and embedded in the OP above; attribution to you.
  10. Arctic Sea Ice Extent: We're gonna need a bigger graph
    The canary finally fell off its perch. Here's an updated version of my raytraced PIOMAS visualization: http://www.youtube.com/watch?v=bNkyJ7eHHhQ I'm still working on the death spiral version. Takes hours and hours of scripting!
  11. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    In reply to geoffchambers at 16:17 PM on 1 September, 2012 the editor wrote: [DB] References to stolen intellectual property, statements about religions & ideology and general off-topic hypothesizing snipped. --------------------------- For the lords sake DB, don't step all over the lead.
  12. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    Tom Curtis #37 Well said. Your point about the two odd outliers has already been made by Manicbeancounter on his blog. Nice to see some agreement about scientific and methodological questions across the great divide. Moderator DB OK. What’s his email address?
    Moderator Response: [DB] At the bottom of every SkS page is the link to the Contact Us form.
  13. Sea Level Isn't Level: This Elastic Earth
    Beautifully presented and please do keep them coming. Complementary item can be found at http://www.abc.net.au/radionational/programs/scienceshow/the-andes3b-formation-and-movement-today/4175684 investigation into big mountain ranges, like Andes, projecting downwards as well as up, like icebergs, except that, from time to time, they lose large lumps into the mantle, causing the crust to flex, similar to above.
  14. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    A (hopefully) final comment on Lewandowski (in press): I have been looking through the survey results and noticed that 10 of the respondents have a significant probability of being produced by people attempting to scam the survey. I base this conclusion on their having reported absurdly low (<2) consensus percentages for at least one of the three categories. An additional response (#861 on the spreadsheet)represents an almost perfect "warmist" caricature of a "skeptic", scoring 1 for all global warming questions, and 4 for all free market and conspiracy theory questions. There may be wackos out there that believe every single conspiracy theory they have heard, but they are a vanishingly few in number, and are likely to appear in a survey with such a small sample size. A second respondent (890) almost exactly mirrored respondent 861 except for giving a 3 for the Martin Luther King Jr assassination, and lower values for the scientific consensus questions. Again this response is almost certainly a scam. Combined, these respondents account for 2 of the strongly agree results in almost every conspiracy theory question; and the other potential scammers also have a noticable number of strong agreements to conspiracy theories. For most conspiracy theory questions, "skeptics" only had two respondents that strongly agreed, the two scammed results. Given the low number of "skeptical" respondents overall; these two scammed responses significantly affect the results regarding conspiracy theory ideation. Indeed, given the dubious interpretation of weakly agreed responses (see previous post), this paper has no data worth interpreting with regard to conspiracy theory ideation. It is my strong opinion that the paper should be have its publication delayed while undergoing a substantial rewrite. The rewrite should indicate explicitly why the responses regarding conspiracy theory ideation are in fact worthless, and concentrate solely on the result regarding free market beliefs (which has a strong enough a response to be salvageable). If this is not possible, it should simply be withdrawn.
  15. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    John Hartz #33 Why on earth should a question about the contents of this blog be addressed to John Cook in a private email? (-Snip-)
    Moderator Response:

    [DB] You have already received a public response from John Cook. Should you wish more detail, please submit an email to him. This is a forum founded and administered by him. Therefore questions of the nature you have been posting should more rightly be submitted to him in private correspondence.

    Continuance in this behavior now constitutes grandstanding and sloganeering, and will be moderated accordingly. FYI.

  16. Global Warming - A Health Warning
    EliRabett - You are right. Smog is a problem in Mexico City and so is ozone, more so than I thought.
  17. Arctic Sea Ice Extent: We're gonna need a bigger graph
    jeffgreen11 @13, it will interest you to know that natice also shows the extent with 20% sea ice, which is most definitely at record low values (3.25 million square kilometers).
  18. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    A further comment on the methodology of the paper: I was talking to my wife about the Lewandowsky paper yesterday. She noted two points in particular. First, the absence of a neutral (I don't know/I know nothing about it) option in the questions was a serious methodological flaw. This is particularly the case for the conspiracy theory questions, in which at least one of the conspiracy theories are obscure (IMO), and not inherently implausible:
    "CYOkla: The Oklahoma City bombers Timothy McVeigh and Terry Nichols did not act alone but rather received assistance from neo-Nazi groups."
    I have never before heard of this conspiracy theory, and it is not inherently implausible that terrorists should receive aid from extremist political groups. Indeed, most terrorists have received such aid. As to whether McVeigh and Nichols did? I have no relevant information. If I had taken the survey, upon coming to this question I would have left it blank. That would be a perfectly rational, and the only honest response. My doing so would have excluded my responses from the sample. The consequence of this lack of a neutral response combined with excluding all results that do not complete all questions is to: 1) Bias the sample by excluding some people who are trying to complete the survey accurately; 2) Force some of those who do complete the survey into more definite responses than they actually hold. In my wife's opinion, this flaw alone is enough to make the survey scientifically worthless; and I trust her judgement on this issue. My wife further said that she would automatically reject a paper with Lewandowsky's title as being politically motivated. In the social sciences, politically motivated papers are a major problem, and generate an excess of background noise and confusion. Part of my wife's response to that is simply to ignore as worthless clearly politically motivated papers. I can see her point, but disagree with the response. Data is data, and so long as you are clear as to how it was obtained, and the results obtained, can be interpreted without consideration of the views expressed in the paper. What is more, in this case the views expressed in the paper are sober analysis. The title makes the paper seem very much worse than it is. Never-the-less, given title, and given the (several) methodological flaws discussed in this post and in my post @12, this has confirmed my opinion that this paper is an "own goal" for opponents of "skepticism" about AGW. It contributes nothing of value scientifically to understanding AGW "skepticism", and its title is a disaster.
  19. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    I agree with Tom about the title. To me it's unnecessarily combative. But the fact that it highlights the "conspiracy" results over the "free-market" results is probably because Dr. Lewandowsky sees that result as being the "new" finding, while the free-market result is already well established. Other than that, people need to pay special attention to what the paper actually says about it's target audience and how the correlation goes. Hint, it is not skepticism about climate science as being all conspiratorial. See Tom's post.
  20. Matt Ridley - Wired for Lukewarm Catastrophe
    Chris@81 I agree that the Schuur and Abbott figures can be confusing (I got them wrong myself previously.) In one sentence they talk about "tonnes of carbon" and in the next explain that by "carbon" they mean "CO2 equivalents". What they wrote was:
    The estimated carbon release from this degradation is 30 billion to 63 billion tonnes of carbon by 2040, reaching 232 billion to 380 billion tonnes by 2100 and 549 billion to 865 billion tonnes by 2300. These values, expressed in CO2 equivalents,combine the effect of carbon released as both CO2 and as CH4.
    My reading of the Matthews et al paper is that the linearity applies up to cumulative emissions of 2 Trillion tonnes of carbon. They wrote:
    Even in the extreme case of instantaneous pulse emissions, the temperature change per unit carbon emitted in the UVic ESCM is found to be constant to within 10% on timescales of between 20 and 1,000 years, and for cumulative emissions of up to 2 Tt C (see Supplementary Fig. 1).
  21. Arctic Sea Ice Extent: We're gonna need a bigger graph
    This was posted at Nevens: blog: For those wondering about the NIC estimates (as can be seen here: http://nsidc.org/data/masie/, NIC produces operational ice analyses, focused on using many data sources of varying quality and quantity to detect as much ice as possible, even small concentrations. NSIDC’s passive microwave data may miss some low concentrations (it uses a 15% concentration cutoff), particularly during melt. So it’s not unusual for NIC/MASIE to show more ice, though it’s more than in other years because the low concentration ice is scattered over a much larger area. An important point is that NIC/MASIE, while picking up more ice, is produced via manual analysis and the data quality and quantity varies. So the product is not necessarily consistent, particularly from year-to-year. NSIDC’s product is all automated and consistently processed throughout the record. So there may be some bias, but the bias is consistent throughout the timeseries. This means that comparison of different years, trend values, and interannual variability are more accurate using NSIDC. Hope this info helps. Walt Meier NSIDC
  22. Arctic Sea Ice Extent: We're gonna need a bigger graph
    Jeff, The NSIDC has posted at several locations on the web, including Realclimate and WUWT, that the IMS ice product includes all ice detected in its extent analysis. The NSIDC includes only areas with at least 15% ice. Therefore the NSIDC is always lower than IMS. Because of the way the data is analyzed, IMS is not comparable from year to year. For this reason it is not useful for long term analysis. It is intended for use by Navy ships for navigation. A lot of the extent IMS currently measures is less than 5% ice and is expected to melt out soon. There is much more low concentration ice this year than there was in 2007. The deniers like IMS since it is the last measure of the ice that is not lower than 2007. Scientists use 15% extent like IJIS and NSIDC because the data is collected and analyzed for the purpose of long term comparisons. Note: Cryosphere Today uses sea ice area and DMI uses 30% extent. It is best to only compare one groups graphs with their own graphs. PIOMAS measures volume which is another animal completely.
  23. Arctic Sea Ice Extent: We're gonna need a bigger graph
    #13 jeffgreen I am not an expert, but that particular chart at the link seems to be updated fortnightly, so it will not be updated again until September 8th. The last date updated is 26th August. Here is another chart from the same site that is updated weekly. http://www.natice.noaa.gov/ims/ Better to wait until well into September until any message can be taken from these particular graphs. I notice Anthony Watts made great play with this second chart - until it got updated.
  24. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    @geoffchambers #31: The bulk of the many questions that you have posted on the SkS comment threads should have been posed directly to John Cook via email. Please stop cluttering this comment thread with an endless stream of queries.
  25. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    Geoff: Does anyone remember what the response was in comments here? Why not ask the expert blog science dumpster divers? Apparently a copy of the entire SkS database ca. 2010 is kept somewhere as an object of obsessive and unhealthy fascination, so other than maintaining a histrionic posture why ask here? John: Is this wild-goose chase really the best and highest use of your time and energy? If laughter and fun are our highest and best purpose then we should sweep off our hats and bow low in recognition of Geoff and Crew's superior efforts.
  26. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    John Hartz (-Snip-) Lewandowsky gave the names of eight blogs as the source of his data. At two of them there is no evidence of the survey having been mentioned. One is totally inactive. The other is the highly active and influential SkepticalScience. John Cook says the post about the survey was deleted after the survey was completed. (Why?) He gave the wrong year, then corrected it on prompting, but still with no precision as to the month. (Why not?) A little more precision would help us to confirm his statement with the Wayback machine. Now we learn from a comment at` http://rankexploits.com/musings/2012/multiple-ips-hide-my-ass-and-the-lewandowsky-survey/ that Kwicksurveys, the free service which conducted the survey, was hacked and all their data lost. This happened in June, just weeks after Lewandowsky had put up a second questionnaire aimed at deniers - which was publicised here and at Watchingthedeniers. I repeat my request. Does anyone here at SkepticalScience remember the survey in August 2010? Or not?
    Response: [DB] Inflammatory tone snipped. [John Cook] I don't remember the month, presumably August or September is the ballpark.
  27. Arctic Sea Ice Extent: We're gonna need a bigger graph
    http://www.natice.noaa.gov/products/ice_extent_graphs/arctic_weekly_ice_extent.html Hoping to understand why this is different from what is in the mainstream information being shown to us. From a conversation on another site there were differences on sea ice figures. Natice sea ice extent does not have the record broken by its own graphs. I put in years 2000 to start and 2012 to end. According to NATICE 2012 has not broken the 2007 low ice extent record. How does NATICE differ in its data from the PIOMASS and others and why?
  28. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    @geoffchambers #29: In my opinion, the hornet's nest about Lewandowsky's research that you stired up on the Bishop Hill blog site is "Much ado about nothing." Is this wild-goose chase really the best and highest use of your time and energy?
  29. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    #28 doug bostrom Thanks to Stephan for the stimulus. Hope he’s enjoying the response. Thanks to John Cook for the correction. The announcement of the survey provoked quite a lot of comment at Tamino’s and Deltoid. Does anyone remember what the response was in comments here?
  30. Matt Ridley - Wired for Lukewarm Catastrophe
    Andy @80, You pointed to an interesting paper about carbon–climate response (CCR) linearity (however your link to "Kate's blog" discussing this paper is broken). I guess in their simulations, they take into account only negative CC feadbacks like seawater invasion/CaCO3 neutralization, although I cannot find any confirmation in the text. Igneous rock weathering does not kick-off in their timescale of 1ka. To me, their CCR linearity applies to the situations of moderate emissions only. Claimed 1.2-1.4 exagram C pulse per dreaded delta T=2K is a very generous allowance. A large pulse like that is likely to trigger positive CC feedbacks including CO2 degassing, CH4 release from permafrost, not to mention albedo change in the Arctic already happening. If they did not consider those, their CCR is underestimated at upper ranges of considered emissions. Finally, it's worth saying that your quote from Schuur and Abbott about possible CH4 release of "232-380 billion tonnes of CO2 equivalent" appears to be incorrect. SA are taking about "tonnes of carbon" here (or at least that's how I read it). BTW, "CO2 equivalent" is a very ambiguous term for me: is it about radiative forcing of CH4 vs. CO2 convoluted with atmosferic lifetime of CH4? Or something more sophisticated that I don't understand? Anyway, in straight GtC, CH4 release in this century by SA is equivalent to 3-4 decades of emissions at current rate. But that's a speculative number, anyway.
  31. Realistically What Might the Future Climate Look Like?
    Bostjan @50, Professor Shellnhuber does not claim that we are committed to an increase of temperature of 2.4 C above the pre-industrial average. Rather, he says that one of his colleagues believes that if anthropogenic aerosol forcings where removed, anthropogenic greenhouse forcings would be sufficient for a temperature increase to 2.4 C. He is careful to (twice) qualify this result as not yet proven. For what it is worth, total anthropogenic GHG forcing as of 2011 was 2.8 W/m^2, representing an equilibrium temperature increase of 2.1 C for the most likely value of climate sensitivity according to the IPCC AR4. It is certainly not clear, however, if, or when the total anthropogenic aerosol load will be reduced to zero so there is no contradiction in Professor Schellnhuber's talk.
  32. Realistically What Might the Future Climate Look Like?
    I apologize to Bostjan whose post I accidentally deleted. It is reproduced below in full:
    "Bostjan at 21:53 PM on 2 September 2012 (Email commenter) @yocta 48 How could "people" understand that we're locked in to at least 2 oC more when even well intentioned people such as Prof Schellnhuber give out completely contradicting massages? If you carefully listen at what he said at the Melbourne conference you'll notice contradicting massages. On one hand he acknowledges that we're already comited ourselves to at least 2,4 oC (20min of his talk) and then goes on showing the graf form Figure 1 as a way to stay below 2oC (40min). He would've been consistent if he'd mentioned some 3,6 -4 oC sulforic acid GE. But he didn't. In the same speech he also clearly says that scientist have to persue their careers, so they won't - in his words - go into really "interesting" topics, but will follow the money. That's why one should be really skeptical about what institutions (IPCC, IAE, WBGU,...) are saying. Not because of the people that work for them, not at all. I have great admiration for their work and achievements. But it's the power of those (politicians) who are employing them that make all the difference. One thing is when you're exchanging ideas about facts with other scientists and completely different when you're advising Angela Merkel, the german version of a tea party leader. What politician will employ scientist who told the truth that we need to tell the public: look, it's really bad, forget your car, your flights to Ibiza and your pensions. There is no politician to pay for that. Try limit maximum speed at autobahn to 90 km/h, let alone telling people they can't drive at all until we've found enough carbon neutral electricity and changed the fleet of millions of internal combustion cars for electric ones. Have to be frank, it's not only politicians who don't want to hear that. Nobody really. Me included. But as Anderson says, unless we face the truth both individually and collectively, there's no way way out of this catastrophe. But it's the scientists whos work must be absolutely clear about the facts."
  33. Arctic sea ice breaks lowest extent on record
    One physical aspect to keep in mind (from discussion at Neven's ASI blog) is that as the freshwater lens underneath the floes has thinned, the thickest remaining sea ice is exposed to ever warmer waters coming up from below due to the fact that thicker ice rides lower in the water. As this lens suffers destratification due to turbidity and storms, the enormous heat contained in the deeper layers is brought into closer proximity to the remaining ice.
    "In the end, it will just melt away quite suddenly."
    - Arctic ice expert Peter Wadhams, 12 December 2007
  34. Arctic Sea Ice Extent: We're gonna need a bigger graph
    Santa's Drowning: Twas the year before the great thaw and all over the land, No deniest were stirring nor any of their band ... (Any good poets out there!)
  35. Arctic sea ice breaks lowest extent on record
    CBD - I agree with you. There are very clearly some important physical aspects still missing from the Arctic sea ice models.
  36. Arctic sea ice breaks lowest extent on record
    villabolo, that likely depends on how big a 'band'... the ice is currently constrained to an area "north of Canada and Greenland". Given the sharp drops in ice volume in 2007, 2010, and now 2012 it seems inescapable to me that we will see 'virtually ice free' conditions this decade... likely within the next five years. The only significant ice volume remaining is the mass of multi-year ice along the northern edge of the Canadian archipelago. The argument for the ice holding out longer has been that this thick older ice will be highly resistant to melt... but I don't buy it. Every time we've seen the ice melt back to the multi-year edge that thick ice has then been broken up by wave action and melted in short order. It is happening right now on the western edge of the archipelago. To me it looks like the only thing which keeps the multi-year ice from melting each year is the protective 'buffer' of thinner ice around it. Once that is gone the multi-year ice is actually quite vulnerable. It is thick enough to not melt out from air and water temperature, but when exposed to waves it breaks up into chunks small enough to melt.
  37. Potential methane reservoirs beneath Antarctica
    Kunzig has an article at National Geographic that has some background on what the authors of this paper have been doing.
  38. Potential methane reservoirs beneath Antarctica
    In the event of a rapid loss of a few hundred metres of ice sheet thickness, it is conceivable that hydrates at the margins of stability could be rapidly destabilized due to a drop in pressure. On the the other hand, hydrates buried at depths of a few hundred metres below permafrost might have to wait for centuries or millennia before heat from the warming surface penetrated to those depths due to low thermal conductivity of rocks and the thermal buffering effect of the overlying permafrost. There's a case to be made, therefore, that hydrates under ice sheets (assuming they exist) may pose a more immediate climate threat than hydrates buried beneath permafrost. For example, Weitemeyer and Buffett (2006) proposed that hydrates under the N American continental ice sheets played a role in the last deglaciation.
  39. Matt Ridley - Wired for Lukewarm Catastrophe
    Jay@79 I did a SkS blogpost on that aspect of Ridley's past, about a year ago. As Monbiot has noted, Ridley has a brass neck to lecture anybody about how risks are overplayed and how government intervention is invariably counter-productive, given his history of presiding over a banking disaster and then begging for a government bailout.Ridley claimed to the subsequent Parliamentary enquiry: We were hit by an unexpected and unpredictable concatenation of events. As Samuel Johnson said (about people who get married for a second time), Ridley's persistent "rational optimism" is a triumph of hope over experience. There's some irony in the fact that Joel Upchurch seems to be supporting Ridley's rosy climate forecast by implying that economic growth will not be anything but exponential, an argument that would be anathema to an economic growth bull and resource cornucopian like Ridley. One last thing, the idea that the temperature increase will be a logarithmic response to cumulative emissions is not correct. Because of diminishing carbon sinks, the temperature response to cumulative CO2 emissions will likely be near-linear as atmospheric concentrations rise. This is explained well at Kate's Climatesight blog. The relevant paper can be downloaded here. Yet one more last thing: projections of greenhouse gas concentrations generally do not incorporate carbon cycle feedbacks. Schuur and Abbott for example, recently did a survey of experts in the permafrost field who forecast that by 2100, there would be an additional 232-380 billion tonnes of CO2 equivalent released from the degradation of organic material in thawing permafrost. That amounts to roughly an additional decade of emissions at current levels by 2100, an amplification to greenhouse gas concentrations that we absolutely don't need.
    Moderator Response: [DB] Andy, your link is broken; was it this one? http://climatesight.org/2012/05/16/cumulative-emissions-and-climate-models/ [Andy S] Yes, thanks. I have fixed it now. Apologies.
  40. Arctic Sea Ice Extent: We're gonna need a bigger graph
    We don't need a bigger graph, we need a smaller carbon footprint.
  41. Matt Ridley - Wired for Lukewarm Catastrophe
    Monbiot wrote on Ridley's philosophy this summer. His time as chairman of Northern Rock coincided with that bank's disastrous failure. Faulty investments required a huge taxpayer bailout by Bank of England in 2007 and led to his resignation. Of course, this hasn't lessened his contempt for the protective role of governments in economics. Consequently, Ridley is an unlikely source of expertise about long-term risks. "Matt Ridley’s irrational theories remain unchanged by his own disastrous experiment." Guardian
  42. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    Here's a thought: Lewandowsky 2012 itself is a stimulus created for the purpose of experimentation. :-)
  43. Matt Ridley - Wired for Lukewarm Catastrophe
    Joel Upchurch @76, I note that a population growth to 9 or 10 billion is a growth by 30 to 40%. As DB notes inline, essentially that means your answer to my question is, that, no, population will not plateau at current levels; and indeed, your estimate is essentially the same as my earlier estimate. Your specific comments about current population growth are, as it happens, incorrect based on the CIA World Fact Book (as reproduced by Wikipedia). They are also, however, of topic, so I will not pursue them.
  44. Matt Ridley - Wired for Lukewarm Catastrophe
    Joel, it would help if you made it clear whether you think the calculations in the SRES scenarios are at fault(which would imply you think a linear extrapolation of current trends is better than SRES methodology) or whether you think the economic and population growth projections of the A scenarios are unlikely. I would note that current CO2ppm is already ahead of A1F1 projection. Which SRES storyline for growth etc is more likely?
  45. Matt Ridley - Wired for Lukewarm Catastrophe
    Tom Curtis @68 Those are very good questions. I can't give you a complete answer tonight, but let me start with B. I first realized that the earth population was peaking when I read "Whole Earth Discipline: An Ecopragmatist Manifesto" by Stewart Brand. It was a shock when I realized that Mexico is at ZPG. Only South America and Africa are still experiencing population growth. The demographic projections are that the world population will peak somewhere between 9 and 10 billion around 2050. (-Snip-)
    Moderator Response:

    [DB] You were asked:

    "b) Or will the human population essentially plateau at current levels, and why?"

    The first portion of your response was on-topic to that question and translates to: No.

    Further off-topic digression snipped.

    Note: In order for SkS to provide you with the information you have requested, you will have to update your profile with a valid email address (part of the Comments Policy requirements).

  46. AGU Fall Meeting sessions on social media, misinformation and uncertainty
    John Cook’s response does not clear the point up, since he mentions a post in 2011, while the fieldwork ended in Oct 2010, according to Lewandowsky’s paper. The six blogs known to have posted the survey all did so between 28th and 30th of August. 2010. Cook says “Skeptical Science did link to the Lewandowsky survey back in 2011 but now when I search the archives for the link, it's no longer there so the link must've been taken down once the survey was over”. But the survey was already over by November 2010.
    Response: [John Cook] My apologies, it was 2010, not 2011 (have updated the original response).
  47. Matt Ridley - Wired for Lukewarm Catastrophe
    Tom Curtis @67. We are not ignoring the pipeline, but it is irrelevant to the question of how much warming we could expect between now and 2100. If we ask a weatherman how hot we expect it to be Wednesday, we don't have to expect the world to end Thursday to expect an answer. (-Snip-)
    Moderator Response:

    [DB] "We are not ignoring the pipeline, but it is irrelevant to the question of how much warming we could expect between now and 2100"

    Completely incorrect, as has been pointed out to you. You are pointedly avoiding dealing with this; this reflects poorly on you.

    Goalpost shift snipped.

  48. Potential methane reservoirs beneath Antarctica
    yocta, your link to Yurganov image is broken. I think you meant to show this link. It's hard to read that image, an eye-balling allows only a vague conclusion that CH4 increased from perhaps 1880 to 1900 ppb around arctic shallows from Nov2008 to Nov2011. Is this increase signifficant trend or just noise? I don't know. At the same time in Mauna Loa, the annual variations appear to be within 1770-1850 ppb. And from their picture within, the same anual cycle appear to apply in the arctic. I think Yurganov's signal is too insignifficant at this point.
  49. Realistically What Might the Future Climate Look Like?
    It may be late in the discussion, but shouldn't someone call Dale's attention to the argument that AGW is a tragedy of the commons?
  50. Will the Wet Get Wetter and the Dry Drier?
    Rob -- Thanks for the Seager reference. I had trouble getting the paper you linked to. However this worked for me. The paper is 2012, btw. I haven't got to the paper yet, but Seager looks like he would be an excellent source for understanding the physics of drought. He has an interesting website and wrt comments @3 and @5 about whether greenhouse gases would bring on El Nino or La Nina and how that would affect the US Southwest, he had this to say : Currently climate models are all over the map in how the tropical Pacific Ocean responds to rising greenhouse gases. The climate modeling group at Lamont has argued that rising greenhouse gases will warm the western tropical Pacific Ocean by more than the eastern ocean because, in the west, the increased downward infrared radiation has to be balanced by increased evaporative heat loss but in the east, where there is active upwelling of cold ocean waters from below, it is partially balanced by an increase in the divergence of heat by ocean currents. As such, the east to west temperature gradient increases and a La Niña-like response in induced. This is the same argument for why, during Medieval times, increased solar irradiance and reduced volcanism could have caused a La Niña-like SST response, as seen in coral based SST reconstructions. If the Medieval period is any guide as to how the tropical Pacific Ocean and the global atmosphere circulation respond to positive radiative forcing then an induced La Niña could regionally intensify the general projected subtropical drying and the American West could be in for a future in which the climate is more arid than at any time since the advent of European settlement.

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