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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 81301 to 81350:

  1. Sea Level Hockey Stick
    There was a controversy about their conclusions (that real proxies didn't have a better skill to reproduce the temperature than random pseudo-proxies), but not on the very fact I mentioned, that you get a hockey stick shape even with random proxies. The exact amount of error introduced by the use of proxies is obviously a very technical point disputed even among specialists. I don't think anybody here (including me) is really competent to say who is right. But to my knowledge, nobody denies that proxies generally introduce a loss of variance in the past.
  2. A Detailed Look at Renewable Baseload Energy
    Tom#59 since nations having a lot of hydro potential have achieved a 100% or almost 100 % renewable power for years, there is obviously inordinate difficulty in doing that without it, or you can't explain why those deprived of enough hydro power haven't. I know of course that geothermal is stable, also it is not the only criterium : the power generation must be able to react quickly to peak demand, which implies the possibility of extra power generation at moderate cost. Hydro (or thermal fuel) storage makes it possible to adjust the instantaneous power without loss of total integrated production, which is not the case for intermittent energy or geothermal. So you can admit a part of renewables (except hydro), but nobody has ever succeeded in doing that entirely, and again, even countries with a lot of renewable power have still a high carbon intensity. The amount of renewable energy, w/o hydro, has increased in 2010 from 137 Mtoe to 159 Mtoe (source BP statistitical review). That's a lot, but it represents only an increase of 0,1 % of the total share of energy (1,2 to 1,3 %). Obviously if you want to reach 100 % before the total exhaustion of fossil fuels, you need a serious acceleration by at least a factor ten or more. I will start to believe in computer simulation when the increase will reach more than a few % a year .
  3. Rob Painting at 16:00 PM on 26 June 2011
    The Last Interglacial - An Analogue for the Future?
    Sentient - "I am not so sure that "The climatic changes during the Eemian happened over several thousand years and not in a few decades" Maybe not the right choice of words perhaps, but I think Steve was referring to the astronomical forcing. The rapid jumps in sea level near the end of the Eemian are likely from the collapse of the Greenland Ice Sheet - not a good omen. Somes_J - as already pointed out, there are different factors in play today, the slight change in ocean circulation between the Pliocene and today (such as restriction of the Indonesian Throughflow) can have a marked effect on regional and global climate. For example this study: A westward extension of the warm pool leads to a westward extension of the Walker circulation, drying eastern Africa - Williams 2011 anticipates warming of the Indian Ocean will dry out East Africa. Check out the SkS post The Dai After Tomorrow, the global drying trend has already begun, and this at a time of globally increasing rainfall!
  4. Miriam O'Brien (Sou) at 15:25 PM on 26 June 2011
    Bob Carter’s climate counter-consensus is an alternate reality
    If you read some of Carter's pieces in Quadrant, you'll find him in a single article saying all of the following: It's warming, it's not warming, it's cooling. He doesn't even know what's happening at all. In a video presentation he said he was 'agnostic' which means he doesn't know if it's warming or cooling and he thinks it cannot ever be known. Carter is a very mixed up man and doesn't know his own mind on the matter. Makes one wonder why he ventures to offer any opinion let alone try to write a book on the subject.
  5. Eric (skeptic) at 15:10 PM on 26 June 2011
    CO2 has a short residence time
    Thanks Tom for explaining the rapid equilibrium with the upper ocean layer. If we posed the hypothetical question, what if mankind doubled or halved his contribution from one year to the next, would the upper layer of the ocean still absorb roughly 50%? Fortunately we can answer that question since nature performs this experiment every year. In the NH fall, the biosphere injects about 7 Pg net C into the atmosphere from (I added the NH amounts in table 3 in Randerson et al.: Trends in Seasonal Cycle of Atmospheric CO2 in Global Biogeochemical Cycles, vol. 11, no. 4, pages 535-560, December 1997). These estimates come from measurements of CO2 released and absorbed by various forest types times their area so are mainly empirical data. The comparable empirical data are the 750 Pg C in the atmosphere, the 390 ppm total and the 7 ppm annual cycle (peak to peak or 3.5 trough to peak). That works out to 6.75 Pg of fluctuation versus 7 Pg from the biosphere (net). There are some caveats, the oceans in the SH have a somewhat complementary cycle when they warm in the NH winter and consequently absorb less CO2 a bit after the the NH biosphere is releasing its annually stored CO2. Irregardless, it is clear that comparing the 6.75 to the 7 means that the top layer ocean in general (although mostly NH) absorbs very little of the CO2 released by the biosphere annually. That means that top layer ocean also does not absorb 50% of man's annual output or anything close to that. A much better numerical match is the 2% of man's total excess as I stated above. Another caveat is that the CO2 annual release doesn't mix worldwide in the atmosphere that quickly, but neither does the fossil CO2 in your scenario (it is also mostly NH). Briefly looking at Archer 2008, he and I agree when he states "Of the 9 Gton C/year carbon release from fossil fuels and deforestation from the year 2000 to 2006, 5 Gton C/year is taken up naturally, half by the ocean and half into the terrestrial biosphere (Canadell et al. 2007). One might conclude from these numbers that the uptake time for CO2 must be only a few years, but this would be a misconception. The rate of natural CO2 uptake in any given year is not determined by the CO2 emissions in that particular year, but rather by the excess of CO2 in the atmosphere that has accumulated over the past century. " Other than that, we aren't talking about the same processes since I am referring to the response of the top layer ocean with reasonable turnover to the deep ocean (I have explained on other threads why the deep ocean turnover is so high, it is the reason that the observed warming lags the theoretical warming). His paper discusses an active ocean and other active GHG production made active by AGW. My spreadsheet assumes (and matches the reality to the current day) that the system is passive.
  6. The Last Interglacial - An Analogue for the Future?
    Hansen et al 2011 warns that we are now a few tenths of a degree below the Eemian and that allowing average global temperature to rise to +2°C above pre industrial will put us over the Eemian maximum. Were that to occur we expose ourselves to decadal doubling of Greenland ice loss, rapid increase in loss of WAIS ice loss, reduction of global albedo and excursion of Arctic carbon, making a 5m rise in sea level by 2100 certain. Hence the call to limit future carbon emissions to 350 ppm by 2050 in order to avoid these outcomes. We are now approaching 400 ppm. Since major CO2 emitters are pursuing BAU, the chances of average global temperatures rising by 4°C or more by 2100 seems pretty good, 3°-4°C above the Eemian maximum and we know what we can expect from that. Moreover, contrary to the views of some, homo sapiens is knowingly achieving this with very little help from other factors and, contrary to the assertions of some, none from the Milankovitch Cycle. The sun is not only quiescent but Earths orbit around it is almost circular and the axial tilt of the earth is gaining such that polar exposure to the sun is decreasing. The world during the Eemian may have had similarities to what it is to-day but it also had significant differences. For example, it was not inhabited by voracious animals, homo sapiens, which have bred to plague proportions. It did not have 7 billion human inhabitants, 4 billion of them living in areas subject to inundation by a 5m sea level rise, 2 billion dependent for water on glaciers most of which will be fully melted by 2100, or 1 billion dependent on marine animals which will be scarce or extinct by then. One would have thought such outcomes would have prompted Australian Prime Minister Gillard to abandon her tokenistic goal of reducing CO2 emissions by 5% by 2020 when all around her are aiming for 25% reduction by 2020, even zero by 2050. Think, Mr Abbott, what these developments are going to do for the economy, competitive advantage and the job protection you bleat about. There are times when pollies – and academics – make you sick! All talk, too little action and total disregard for the consequences.
  7. The Last Interglacial - An Analogue for the Future?
    sentient: Hope your vacation is productive. As always, you provide well documented thoughts in this area.
  8. A Detailed Look at Renewable Baseload Energy
    @ okatiniko. At present, most renewable energy around the world is set up strictly with *peak* power production in mind-which is fine when it only makes up 5%-15% of total demand. However, as the proportion of electricity obtained from renewable sources continues to grow, you'll see a switch towards stable base-load capable versions of existing forms of renewable energy. Of course you continue to refuse to even admit that the Geothermal Power of Iceland, Hawaii & New Zealand all meet the criteria of *stable* base-load power...i.e. that it is power that doesn't vary in output regardless of the time of day or night. Germany & the State of Texas are already making moves towards making their renewable energy sources more stable-with Germany switching to pumped storage & Texas switching to Compressed Air. So you see that Governments are already waking up to the Fossil Fuel Industry lie that renewable energy can't generate stable, base-load power.
  9. A Detailed Look at Renewable Baseload Energy
    MattJ, as Dana rightly points out, there is a massive difference between CO2 that is part of the natural Carbon Cycle, & the CO2 that was part of a Carbon Cycle from millions of years ago. If a power station is converting more harmful methane to CO2, then its doing us a favor-especially if we also make the effort to capture & re-use some of the CO2 produced as either fuel or electricity. Additionally, if it prevents the combustion of fossil fuels, then this is also a good thing. Obviously I'd rather we rely more on truly zero emission technologies, but I still thing bio-electricity has a place in future energy grids.
  10. Rob Honeycutt at 10:46 AM on 26 June 2011
    Bob Carter’s climate counter-consensus is an alternate reality
    heystoopid... I actually find a few published papers on paleoclimate that Carter has published. At very best he has a very thin resume of actual work in this field which he comments so profusely and inaccurately on.
  11. The Last Interglacial - An Analogue for the Future?
    Unfortunately, I must exit further discussion at this time. Preempted by vacation. Laptop is next on the final packing list, and where I am going the only connection is with nature. I will check back on 5Jul11. Be good.
  12. Bob Carter’s climate counter-consensus is an alternate reality
    Ouch! Reading Bob Carter's anti-science propaganda drivel, hurt my brain. Amazon's internal book review hyperbole "Professor Robert Carter - Professor Robert Carter is one of the world's leading palaeoclimatologists, and his work investigates the past cycles of the earth's unpredictable natural climate change, especially over the last few million years of planetary ice ages." Desmogblog: Bob Carter:http://www.desmogblog.com/rm-bob-carter Perhaps, those who have managed to read this anti-science book, could dispel the myths of how a geologist, who has published zero peer reviewed research papers on palaeoclimatology, became an overnight expert in that subject.
  13. pharmacy tech at 10:09 AM on 26 June 2011
    Bob Carter’s climate counter-consensus is an alternate reality
    The carter reality ignored the evidence presented to confirm global warming. Some agree with him but personally I don't Robert
  14. A Detailed Look at Renewable Baseload Energy
    okatiniko, I have noticed that no nation without large scale hydro or geothermal power has yet tried to convert to 100% renewable electricity generation. Therefore the notion that there is some inordinate difficulty in doing so is entirely theoretical, and is not based on empirical observations, at least as you judge these things. Therefore, logically your entire opinion on this subject is that you have no opinion one way or the other. One wonders then why you keep flapping your jaws. If perhaps, you have noted that wind power is intermittent and that solar power is intermittent, and concluded there may be some difficulty, that is very interesting, but invokes a different standard of evidence to that which you invoke to maintain your supposedly agnostic position. Allowing the same standard of evidence, we can then note that there are currently operational solar power plants that can operate in hours of darkness by means of thermal storage of energy. Examining the details of current technology, therefore, shows no impediment to 100% renewable electricity. This point has now been raised several times by several people, and you have just ignored it, and restated your original, and irrelevant objection. That sort of response is called "trolling".
  15. Bob Lacatena at 08:46 AM on 26 June 2011
    Sea Level Hockey Stick
    okatiniko, Have you done any appropriately skeptical research to see if McShane and Wyner has any flaws as a paper?
  16. Bob Carter’s climate counter-consensus is an alternate reality
    "It has also ignored the evidence that carbon dioxide concentrations in the atmosphere are higher than the concentrations in the upper layers of the ocean, so there is a net flow of carbon dioxide from the atmosphere into the ocean." This statement needs a little clarification: How do you compare a concentration of CO2 in the atmosphere (a gaseous phase) with that in the ocean (a liquid phase)? There's a correspondence between the partial pressure and the concentration (Henry's law) in equilibrium; but I think a slightly more careful statement is needed.
  17. arch stanton at 07:32 AM on 26 June 2011
    Bob Carter’s climate counter-consensus is an alternate reality
    The parallel ant-science universe; universe modoki. I agree with Don’s comment (#1).
  18. Philippe Chantreau at 07:14 AM on 26 June 2011
    The Last Interglacial - An Analogue for the Future?
    Somes_J, I'm not sure that this comparison is so useful, now that the Isthmus of Panama is closed. A lot of things have changed since the mid-Pliocene. It is an interesting exercise in modeling, but probably not as good an indication for our future as what model results with current conditions and geography yield.
  19. A Detailed Look at Renewable Baseload Energy
    "@ okatiniko, you asked which countries had *stable* sources of renewable energy-namely sources capable of producing 24/7 power-" I asked which countries had stable power without hydro or fossil fuel , and Iceland definitely doesn't fits the description since it has also a lot of hydro power. Now don't ask me to prove it is impossible, because I never claimed that. I just said it is still to be proved. Man has walked to the moon, but didn't go to other stars, although many people think it could. This is also yet to be proved. You're inverting the burden of the proof. "The point is that any lack of 100% Renewable Energy has much more to do with a lack of political will than a lack of technical feasibility" And so magically this lack of political will didn't prevent countries like Norway and Iceland to have 100 % renewable energy ? how do you explain that policymakers love water, but not air and sun ?
  20. The Last Interglacial - An Analogue for the Future?

    Eric the Red: "Here is were the theories diverge. Some state that an expansion of the ITCZ will simply push the desert regions poleward, causing the semi-arid regions to dry into deserts. Others maintain that the deserts will shrink in size as the ITCZ expands, but the poleward side of the desert remain where htey are today." It seems to me that this question might be testable by looking at whether deserts moved north in previous warm eras. It occurs to me that perhaps a better model for a global warming world would be the Mid-Pliocene rather than the Eemian, as the greater warmth of the Mid-Pliocene may have been due to higher than present CO2: LINK I have managed to find a paper that has a reconstruction of Middle Pliocene ecosystems: http://pubs.usgs.gov/of/1999/of99-535/ From their summary: "Expansion of evergreen forests to the margins of the Arctic Ocean, a reduction of desert area in equatorial Africa and essential elimination of polar desert and tundra regions in the Northern Hemisphere. A small amount of deciduous vegetation occurred at the edge of the Antarctic continent." They include vegetation maps. There's still a large barren area in Africa but it's smaller than today. Barren areas generally seem to be smaller than today. If the Mid-Pliocene warmth was because of higher CO2 it seems that CO2-caused warming also leads to less desert, not more. Any difference between the Mid-Pliocene and today that might explain why deserts would have been smaller than, but you'd have increasing tropical aridity from warming today?

  21. Philippe Chantreau at 06:35 AM on 26 June 2011
    The Last Interglacial - An Analogue for the Future?
    I find a lot of speculation in Sentient post, about a subject that is itself much speculated about. D.O. events, Heinrich events and the more recent Bond events (of which only a few can be conclusively linked to large scale climate fluctuations) are most likely the results of oceanic currents modifications due to disruptions by fresh water. There has not been a D.O. event in over 20k years, yet no ice age has started, even though we've been at only 285 ppm for all of that time. The bipolar ocean seesaw indicates that these "cycles" (true cyclicity is questionable) are mostly about redistributing heat. If Bond events truly are cyclic, then the present warming does not correspond at all to a Bond event. I'd add that nobody is advocating reducing CO2 concentration but rather preventing it from increasing in a way that has no known geologic equivalent during mankind's presence. A "natural" outgassing like we're seeing now, if coming from volcanoes, would require a volcanic activity about 150 times more intense than what it presently is. Whatever else is "naturally happening" according to Sentient is bound to be profoundly affected. This link has lots of good info and references.
  22. Bob Carter’s climate counter-consensus is an alternate reality
    "In the Carter reality, the increase in global temperatures due to a doubling of carbon dioxide is low, only about one degree. This is a strange thing to mention as, in that world, there is supposed to be no warming . . ." That reminds of Lord Monckton's "reality". He claims that a doubling of CO2 (400-800 ppm) will give us as little as 1F maybe .5. That's due to CO2 having 1/6 the insulating effect as real socialist scientists claim. However, in his alternative "Snowball Earth" reality, CO2 was at 300,000 ppm (only 30% of our atmosphere). And, lo and behold, such amounts could not so much as melt a single ice cube.
  23. Bob Carter’s climate counter-consensus is an alternate reality
    Good article and a nice metaphor: "This would be like saying that winter is not colder than summer because a very hot day in winter might happen to have much the same temperature as a very cold day in summer, ignoring all the other days." Thanks for the review, Don
  24. A Detailed Look at Renewable Baseload Energy
    MattJ - there's a big difference between releasing carbon which is already circulating in the natural carbon cycle, and releasing carbon from fossil fuels. As for "where is the 100%?", you answered that yourself. Some of the plans and case studies include gas turbines - which as the article notes, can burn renewable bio materials - and some don't. I have to say, it surprises me how many commenters have a "can't do" attitude.
  25. Stephen Leahy at 05:28 AM on 26 June 2011
    A Detailed Look at Renewable Baseload Energy
    It's also early days for renewables. A mere pittance has been invested in R&D compared the the multi-billions nuclear energy has received from governments since 1950.
  26. Sea Level Hockey Stick
    les : the replication of hockey sticks by random pseudo proxies has been made by several authors, including Mc Shane and Wyner . It is nowhere said in deep climate that random pseudo proxies do not generate hockey sticks, the only controversy is about how far it affects reconstruction methods. I must admit that I am not competent enough to say who is right, and you aren't probably either.
  27. Stephen Leahy at 05:23 AM on 26 June 2011
    A Detailed Look at Renewable Baseload Energy
    Great summary Dana. Okatiniko's main objection seems to be a dislike of computer simulations which most of these studies did not use, certainly not in the sense of computer modelling. A lot of very smart people spent months and even years working on those studies and they were already critiqued by independent experts before release. So Okatiniko's objections are well... I do agree implementation is the real challenge. That said Germany is going for 80% renewable (no hydro is speak of there) by 2050. Germany is doing it for the economic and tech advantages it will give them. My article on Europe's commitment to renewables for the $$$ Postponing Emissions Cuts Carries Steep Price
  28. The Last Interglacial - An Analogue for the Future?
    Then again it just might be worse than we thought. But what about that 6th interglacial, the one that wasn’t on the half-precessional “clock”. That would be MIS-11 (or the Holsteinian) which according to the most recently published estimate may have lasted on the order of 20-22kyrs, with the longest estimate ranging up to 32kyrs. Loutre and Berger’s 2003 paper was soon followed by another landmark paper by Lisieki and Raymo (Oceanography, 2005), an exhaustive look at 57 globally distributed deep Ocean Drilling Project (and other) cores (Figure 1), which stated: “Recent research has focused on MIS 11 as a possible analog for the present interglacial [e.g., Loutre and Berger, 2003; EPICA community members, 2004] because both occur during times of low eccentricity. The LR04 age model establishes that MIS 11 spans two precession cycles, with 18O values below 3.6o/oo for 20 kyr, from 398-418 ka. In comparison, stages 9 and 5 remained below 3.6o/oo for 13 and 12 kyr, respectively, and the Holocene interglacial has lasted 11 kyr so far. In the LR04 age model, the average LSR of 29 sites is the same from 398-418 ka as from 250-650 ka; consequently, stage 11 is unlikely to be artificially stretched. However, the June 21 insolation minimum at 65N during MIS 11 is only 489 W/m2, much less pronounced than the present minimum of 474 W/m2. In addition, current insolation values are not predicted to return to the high values of late MIS 11 for another 65 kyr. We propose that this effectively precludes a ‘double precession-cycle’ interglacial [e.g., Raymo, 1997] in the Holocene without human influence.” To bring this discussion up to date, Tzedakis, in perhaps the most open peer review process currently being practiced in the world today (The European Geosciences Union website Climate of the Past Discussions) published a quite thorough examination of the state of the science related to the two most recent interglacials, which like the present one, the Holocene (or MIS-1) is compared to MIS-19 and MIS-11, the other two interglacials which have occurred since the Mid Pleistocene Transition (MPT) and also occurred at eccentricity minimums. Since its initial publication in 2009, and its republication after the open online peer review process in March 2010, this paper is now also considered a landmark review of the state of paleoclimate science. In it he also considers Ruddiman’s Early Anthropogenic Hypothesis, with Ruddiman a part of the online review. Tzedakis’ concluding remarks are enlightening: “On balance, what emerges is that projections on the natural duration of the current interglacial depend on the choice of analogue, while corroboration or refutation of the “early anthropogenic hypothesis” on the basis of comparisons with earlier interglacials remains irritatingly inconclusive.” The picture which emerges is that the post-MPT end interglacials appear to be populated with dramatic, abrupt global climate disruptions which appear to have occurred on decadal to centennial time scales. Given that the Holocene, one of at least 3, perhaps 4 post-MPT “extreme” interglacials, may not be immune to this repetitive phenomena, and as it is half a precession cycle old now, and perhaps unlikely to grow that much older, this could very well be the natural climate “noise” from which we must discern our anthropogenic “signal” from. If we take a stroll between this interglacial and the last one back, the Eemian, we find in the Greenland ice cores that there were 24 Dansgaard-Oeschger oscillations (Figure 5, originally figure 1. Sole et al, 2007), or abrupt warmings that occurred from just a few years to mere decades that average between 8-10C rises (D-O 19 scored 16C). The nominal difference between earth’s cold (glacial) and warm (interglacial) states being on the order of 20C. D-O events average 1470 years, the range being 1-4kyrs. Sole, Turiel and Llebot writing in Physics Letters A (366 [2007] 184–189) identified three classes of D-O oscillations in the Greenland GISP2 ice cores A (brief), B (medium) and C (long), reflecting the speed at which the warming relaxes back to the cold glacial state: “In this work ice-core CO2 time evolution in the period going from 20 to 60 kyr BP [15] has been qualitatively compared to our temperature cycles, according to the class they belong to. It can be observed in Fig. 6 that class A cycles are completely unrelated to changes in CO2 concentration. We have observed some correlation between B and C cycles and CO2 concentration, but of the opposite sign to the one expected: maxima in atmospheric CO2 concentration tend to correspond to the middle part or the end the cooling period. The role of CO2 in the oscillation phenomena seems to be more related to extend the duration of the cooling phase than to trigger warming. This could explain why cycles not coincident in time with maxima of CO2 (A cycles) rapidly decay back to the cold state. ” “Nor CO2 concentration either the astronomical cycle change the way in which the warming phase takes place. The coincidence in this phase is strong among all the characterized cycles; also, we have been able to recognize the presence of a similar warming phase in the early stages of the transition from glacial to interglacial age. Our analysis of the warming phase seems to indicate a universal triggering mechanism, what has been related with the possible existence of stochastic resonance [1,13, 21]. It has also been argued that a possible cause for the repetitive sequence of D/O events could be found in the change in the thermohaline Atlantic circulation [2,8,22,25]. However, a cause for this regular arrangement of cycles, together with a justification on the abruptness of the warming phase, is still absent in the scientific literature.” In their work, at least 13 of the 24 D-O oscillations (indeed other workers suggest the same for them all), CO2 was not the agent provocateur of the warmings but served to ameliorate the relaxation back to the cold glacial state, something which might have import whenever we finally do reach the end Holocene. Instead of triggering the abrupt warmings it appears to function as somewhat of a climate “security blanket”, if you will. Therefore taking into consideration the precautionary principle, we are left to ponder if reducing CO2’s concentration in the late Holocene atmosphere might actually be the wrong thing to do. The possibility consequently exists that at perhaps precisely the right moment near the end-Holocene, the latest iteration of the genus Homo unwittingly stumbled on the correct atmospheric GHG recipe to perhaps ease or delay the transition into the next glacial. Under this analysis “Skeptics” and “Warmists” thus find themselves on the mutual, chaotic climate ground where the efficacy of CO2 as a GHG had better be right.
  29. Phil Jones - Warming Since 1995 is now Statistically Significant
    The article says, "This reactions to this story have revealed a number of media outlets whose aim is not to accurately inform their readers with regards to the climate, but rather to misinform them." But is this a surprise to anyone? It should not be. The press has been abusing freedom of speech this way for many decades now. It has only become worse with greater and greater consolidation of corporate ownership of the press (Murdoch being only one unsavory example). If there is anyone to look back on what went wrong 300 years from now, they might well say that this failure proves that the exalted democratic principles of "freedom of speech" and "freedom of the press" were the cause of global warming -- and the downfall of a lot more than just democracy.
  30. Rogues or respectable? How climate change sceptics spread doubt and denial
    "Doubt is our product, since it is the best means of competing with the ‘body of fact’ that exists in the minds of the general public. It is also the means of establishing a controversy." Said by a tobacco industry executive: "People generally do not favour action on a non-alarming situation when arguments seem to be balanced on both sides and there is a clear doubt. The weight of impressions on the public must be balanced so people will have doubts and lack motivation to take action. Accordingly, means are needed to get balancing information into the stream from sources that the public will find credible. There is no need for a clear-cut ‘victory’. [...] Nurturing public doubts by demonstrating that this is not a clear-cut situation in support of the opponents usually is all that is necessary." Said by a Tobacco Industry Lobbyist
  31. The Last Interglacial - An Analogue for the Future?
    Steve, I am not so sure that "The climatic changes during the Eemian happened over several thousand years and not in a few decades." As early as at least 2001 Hearty and Neumann (Quaternary Science Reviews 20 (2001) 1881–1895)suggest that: "Recent evidence indicates that the close of MIS 5e was marked by sudden changes in sea level and climatic events ofcatas trophic proportions. These rapid sea level changes were accompanied by powerful waves that struck the eastern margin ofthe Bahama Banks, significantly reshaping the geomorphic face and facies of this critical interval (Hearty and Kindler, 1995; Neumann and Hearty, 1996; Hearty, 1997; Hearty et al., 1998; Tormey et al., 1999; Hearty and Kaufman, 2000)." "From these findings, it is reasonable to surmise that the close ofthe present interglacial may be marked by equally dramatic climatic changes." "Thus, we interpret these events to have occurred late in MIS 5e after the formation of multiple, smaller ridges which are observed in outcrop at numerous sites (Hearty and Kindler, 1997). That emplacement ofthese dunes was relatively rapid is inferred from the burial of large standing trees (Fig. 6) and palmetto leaves in living position (Neumann and Hearty, 1996)." "The geology ofthe Bahama Islands provides critical outcrop information from which sea level and climate history between 132 and 118 ka can be reconstructed. Within that period, three oscillations ofsea level can be distinguished. Early in the period (132–125 ka) sea level appears to have maintained a level around +2.5m as evidenced by reefs capped by A. palmata at that datum. A mid 5e regression around 124 ka is documented by a mid-5e unconformity and from numerous beach, reef, and dune sections (Chen et al., 1991; Hearty and Kindler, 1993, 1997, 1998; White et al., 1998). Sea level rose again to a slightly higher level than the previous one, which again initiated reefgrow th to a maximum elevation of less than +3m. This near stillstand was short lived, however. At the end of the period, sea level rose to +6 to +8.5 m, flooding areas ofthe platform inland ofthe coastal ridge and cutting notches into sea cliffs of older material. A rapid fall followed which permitted the preservation of antecedent morphology, stranded storm beaches and local reeftops left in near pristine condition (Fig. 4)." More recently Boettger et al (Quaternary International 207 (2009) 137–144) provide a European analysis of the late Eemian climate instability: "The transition (MIS 5e/5d) from the Last Interglacial (Eemian, Mikulino) to the Early Last Glacial (Early Weichselian, Early Valdai) is marked by at least two warming events as observed in geochemical data on the lake sediment profiles of Central (Gro¨ bern, Neumark–Nord, Klinge) and of Eastern Europe (Ples). Results of palynological studies of all these sequences indicate simultaneously a strong increase of environmental oscillations during the very end of the Last Interglacial and the beginning of the Last Glaciation. This paper discusses possible correlations of these events between regions in Central and Eastern Europe. The pronounced climate and environment instability during the interglacial/glacial transition could be consistent with the assumption that it is about a natural phenomenon, characteristic for transitional stages. Taking into consideration that currently observed ‘‘human-induced’’ global warming coincides with the natural trend to cooling, the study of such transitional stages is important for understanding the underlying processes of the climate changes." If we couple that with the just as long running debate on the probable length of the Holocene we find that 5 of the last 6 post-MPT interglacials have each lasted roughly half a precessional cycle. The precessional cycle varies from 19-23kyrs and we are at the 23kyr point now. The Holocene is often stated as being ~11,500 years old now, exactly half of the present precessional cycle. Which is why this discussion has relevance.
  32. A Detailed Look at Renewable Baseload Energy
    @quokka #31 France sells its excess electric power during the night to Britain, where they store it by pumping water up into towers. Then just in time for morning tea, the British recover the power by letting the water flow down. So although they do not turn down the power as much as you seem to imply, they don't let it go to waste either (except for cross-Channel line-loss), as the article implies for other baseload generators.
  33. A Detailed Look at Renewable Baseload Energy
    @dana1981 #22: Carbon is carbon, and carbon is what we put too much of in the air. It doesn't matter whether it was trapped underground for millions of years or not before, it will have a greenhouse effect. So that is why I have to shake my head when people insist that carbon from renewable sources is OK. But I also have to wonder: this article boldly proclaims early on that "a transition to 100% energy production from renewable sources is possible within the next few decades", but then in several examples, shows baseload met only by assisting with gas turbines or the like. So where is the 100%? Finally, we have to beware of generalizations that held up fine in the case of small countries with special geography, but fail when generalized to big ones like the US. Even in Kansas, the wind does not blow all the time, and sometimes it blows too much, risking damaging the wind farms. Has anyone yet made a wind farm that can withstand a Kansas tornado? Likewise for solar: Spain may do fine with molten salt to cover the night time, but countries at higher latitudes, like Canada and Russia will not. And they need to distribute that power over a much wider geographic region while it is available, too. Suddenly, line-loss becomes a significant factor. Did your simulations take all these into account? I can't tell from the article.
  34. Sea Level Hockey Stick
    skywatcher, I said that it was very unlikely that climate scientists would choose proxies totally uncorrelated with temperature. However, they are not 100 % correlated as well - or they would be also strictly correlated to each other. So the issue here is the amount of variance due to temperature, and the amount of variance due to other factors. Obviously the calibration procedure doesn't know which is which. In some extreme cases, such as the (in)famous Tiljander series, parasite modern phenomena have inverted the proxy. Obviously in this case, the calibration procedure will turn it upside down in the past. This can only lower the variance of the past reconstruction signal since it adds a negative temperature component. This has been corrected in later studies by screening the polluted period, but it shows the problem can be real.
  35. A Detailed Look at Renewable Baseload Energy
    okatiniko said: "...there is no country with almost 100 % renewable electricity without a large part of hydropower..." Maybe, but that is based on current renewable technologies and grid systems that were designed with large central power stations in mind.
  36. Pete Dunkelberg at 02:02 AM on 26 June 2011
    Rogues or respectable? How climate change sceptics spread doubt and denial
    ScaredAmoeba, here is some information on how professional deniers make Hockey sticks. It is a little bit technical, but it may help explain the confusion that is found in some quarters.
  37. Pete Dunkelberg at 01:48 AM on 26 June 2011
    Rogues or respectable? How climate change sceptics spread doubt and denial
    Things to know: The Denialists' Deck of Cards, and note that denialism is often industry-based behind the scenes. What Eli adds. And if you try to really get to the bottom of it, it takes long hard work to discover how low it goes.
  38. Linking Extreme Weather and Global Warming
    Eric the Red @224, the Munich Re report states what has occurred, but it also states "... for which we believe climate change is partly responsible ..." and when stating how they assess the risk that say, "We adopt a multidisciplinary approach, using and combining the pertinent experience and expertise of our scientists, specialist underwriters, lawyers, economists, sociologists and actuaries as appropriate for the risk situation." Consequently, they do not say how somebody else attributed responsibility for the increase in extreme weather events, but how they attribute that responsibility. Further, it is based on that attribution that they consider the risk that extreme weather events becoming so frequent that insurance becomes impractical is real, and something they are spending share holders money now to prepare for. This probably says nothing more than that their scientists accept the scientific consensus on global warming, and absence access to peer reviewed studies by the scientists, that is neither here nor there. But they do not reflect "what if" scenarios nor attribute to others these beliefs. Rather they are, and are legally required to be, the considered views of the board of directors. Having said that, the only evidence of weight in their report and other documents is to the question of whether or not extreme weather events are on the increase. The answer is yes. Interestingly that is something predicted by the theory of AGW, and something not predicted by any opposing theory. Coupled with the evidence provided above about the effects of increased tropical pacific sea temperatures on the frequency of ENSO events, and the evidence of the increased frequency of tornadoes (though not the largest tornadoes), that should answer Norman's question.
  39. Rob Honeycutt at 01:42 AM on 26 June 2011
    A Detailed Look at Renewable Baseload Energy
    okatiniko... Whether there are any 100% renewable markets is a rather pointless argument. It's like complaining that no one has ever walked on the moon at the point when Neal Armstrong was in the capsule sitting on top of his Saturn 5 rocket. Like it or not there are a lot of people working on creating a 100% renewable energy grid. There are billions of investor dollars flowing into this effort. You might not think it's possible but those billions of investor dollar are all saying they don't agree with you.
  40. Pete Dunkelberg at 01:38 AM on 26 June 2011
    Rogues or respectable? How climate change sceptics spread doubt and denial
    Oh brother. Just google Galileo gambit.
  41. Eric the Red at 01:23 AM on 26 June 2011
    Linking Extreme Weather and Global Warming
    The Munich Re report is neither an advocation for or against global warming. The report simple states that weather-related natural catastrophies are on the rise and evidence is that this is partly due to climate change. This is a very legalistic statement, which simply states what has occurred, and how someone else has attributed some blame. They then state that temperature increases should be kept below the much-cited two degrees to continue adequate insurance protection. Again, no claim either way. All these statements, and more, are "what if" scenarios, and that the insurance industry should position itself accordingly. While not exactly a scientific paper, insurance reports are based on real data, and risks are calcaulated based on past events and future probabilities.
  42. A Detailed Look at Renewable Baseload Energy
    @ okatiniko. So please be so kind to provide some kind of *evidence* that proves Bio-gas is incapable of providing 24/7 electricity. Provide us with evidence that Micro-Hydro, which is *not* limited by geographic conditions (as there are very few-if any-Countries in the World that don't have access to at *least* one river system) is incapable of providing 24/7 electricity. Show us *evidence* that Tidal, Wave or Tidal Stream power are incapable of providing stable 24/7 power? Indeed, show us *evidence* that any source of renewable energy is incapable of providing stable 24/7 power? The point is that any lack of 100% Renewable Energy has much more to do with a lack of political will than a lack of technical feasibility-a fact that you clearly have no interest in coming to grips with.
  43. Eric the Red at 01:09 AM on 26 June 2011
    Websites for Watching the Arctic Sea Ice Melt
    Michael, If you remember, this all started when you stated that if CO2 were stopped today, that temperatures would continue to rise for several decades, and sea level would increase several meters. I agree that CO2 emissions will not end today, tomorrow, or this decade. I made no estimate of the decline of atmospheric CO2 after that point, but merely stated that would - others have provided links to various decline rates. With regards to the sea ice trends, using the volume graph provided by Albatross in 106 and corresponding reference, the accelerating decline would reach zero by about 2015. The trend based on the sea ice area, even using the steeper decline since 1996, would take 30 years. Unless an infintely thin 5 million square km sheet of ice forms in the intervening decades, one of those proejections will have to be wrong. (mathematically a large area with zero height will result in zero volume, but physically, it is impossible). I have never advocated taking no action. I do not know were you get these ideas. I simply stated that if we waited, action will be harder, and that effects thus far (not sometime in the future) are reversible (I also never said easily). While I will admit to presenting what amounts to optimistic forecasts, oftentimes, they are a counter to those who are using the more pessimistic. For most forecasts, there is a wide range of possibilities, due to large uncertainties, which have not been resolved yet.
  44. A Detailed Look at Renewable Baseload Energy
    @ okatiniko, you asked which countries had *stable* sources of renewable energy-namely sources capable of producing 24/7 power-& Iceland definitely fits the description with its Geothermal Energy. I do find it odd that those who try & defend the current fossil fuel monopoly of our electricity sector use extremely lame excuses to justify the continuation of said monopoly-just as you do. The fact is that the first coal-fired power stations were extremely expensive, inefficient & unreliable. It took a good 50 years for them to reach the price & reliability that we know today. Yet if we applied your false logic, then we'd have just abandoned the whole thing as a bad idea from the get-go.
  45. A Detailed Look at Renewable Baseload Energy
    Marcus, ( -snip- ). I asked you a very precise question, I didn't ask you to repeat arguments that I already know. And Iceland has a lot of hydroelectricity, too. The fact is : there is no country with almost 100 % renewable electricity without a large part of hydropower, and it is limited by geographic conditions. And there is no country with almost 100 % renewable electricity and without CO2 production. This doesn't demonstrate it is impossible : it only demonstrates that the feasibility of "100 % renewable energy" is still to be demonstrated, and that computer simulations and peer-review reports don't demonstrate they're right.
    Response:

    [DB] Refrain from personalizing the discussion, please.

  46. CO2 has a short residence time
    Eric (skeptic) @96, what the environment does is restore equilibrium between the partial pressure of CO2 in the atmosphere and the partial pressure of CO2 in the upper layer of the ocean. That is a rapid process, sufficiently rapid that even temperature fluctuations of 0.2 degrees C globally averaged can significantly affect the rate of absorption. That would not be the case if the surface and atmosphere where far from equilibrium. Consequently, the idea that the environment absorbs ~50% of annual emissions is much closer to the truth than that it absorbs 2% of the difference between current and pre-industrial CO2 levels. I can make the same point from a different direction. The fact is that ~50% of CO2 emissions have been absorbed annually since the industrial revolution. The rate of absorption is a function of the level of disequilibrium. Given that the rate of absorption has scaled with annual emissions rather than with cumulative emissions since 1850, it follows that the level of disequilibrium correlates with annual emissions rather than cumulative emissions. From that it follows that equilibrium is reached in a time scale close to one year. In the long term, CO2 levels will reduce despite this, because partial pressures of CO2 in the deep ocean and surface will equalize, gradually drawing down atmospheric CO2 to between 25% and 30% above peak values. After that the CO2 is only drawn down by geological processes, ie, over thousands of years. So, to conclude, your spreadsheet is based on a clearly false assumption. Again I refer you to Archer 2008. Or perhaps you will be content with Archer's rule of thumb (now considered optimistic), that CO2 will reduce to 25% increase over pre-industrial levels over a century, and that the remainder is there forever on human time scales. (I refer you to the charts posted by Dikran Marsupial @23.)
  47. A Detailed Look at Renewable Baseload Energy
    @ okatiniko "They don't replace coke powered ironworks." If this were true, then its all the more reason not to be wasting the coal in power stations when we could-& should-be using renewable sources of energy instead. Just as we should be saving our oil to make all those things that can currently only be made without oil, instead of wasting it in inefficient Internal Combustion Engines, when cleaner & more efficient sources of fuel are available. "can you please list me the number of those producing a stable power supply, without coal or hydroelectricity ?" Again with your hearing problem. By your argument we should never have flown a plane because, by your logic, if no-one has done it yet then it must be *impossible*. Iceland, though, has entirely stable Geothermal Energy &, as I've already pointed out, Micro-hydro & Bio-Gas Electricity are entirely capable of providing completely stable power without *any* need for storage-& are readily available to virtually every nation on Earth. So too can Tidal Power, Wave-power & Tidal Stream Power. The only renewable energy sources that require some kind of back-up or storage is solar & wind, but with the right back-up these two are entirely capable of providing stable power. Not that coal or nuclear are as stable as some would have us believe. Both types of power are usually highly centralized, & so need to transmit their electricity over a wide geographic area-so what happens if a sub-station blows up, or a fire or wind-storm brings down any one of the hundreds of kilometers of High Voltage Power Lines linking the power station to the consumers? What happens if the power station breaks down? These things are likely to have a much more damaging effect than if a single wind turbine breaks down, or if a single solar dish breaks down or if....well you get the picture. The point is that almost all the existent sources of renewable energy are (a) modular & (b) relatively small size-so they tend to distribute their energy over a much smaller area, & so are less prone to T&D failures. Their modular nature, as I suggested above, means the loss of a single power generation unit will *not* bring the whole system crashing down!
  48. Eric (skeptic) at 23:38 PM on 25 June 2011
    Websites for Watching the Arctic Sea Ice Melt
    michael, I answered you here: /argument.php?p=2&t=94&&a=80#55874
  49. Eric (skeptic) at 23:36 PM on 25 June 2011
    CO2 has a short residence time
    michael, yes my spreadsheet is completely academic since I stopped CO2 in 2008 (I only had CO2 data through 2007) and we are current increasing worldwide, not stopping. Yes, I will take your suggestion and redo it with a somewhat plausible scenario and a BAU for comparison. The back of envelope calculation that supports my estimate is this: the environment is said to absorb 1/2 of our new CO2 each year. But it does not and can not possibly do that. Instead it absorbs about 2% of our total remaining excess over preindustrial (818,000-597,000). Even that is very oversimplified. If it were linear it would be removed in 100 years, or half in 50 years. It clearly is not for the reasons you point out. I would add that warming since the end of the LIA would have increased CO2 by 5-10 ppm had man done nothing at all. But I think an exponential decay to preindustrial is a reasonable estimate until we have more evidence for permafrost melting, etc (those are extremely slow processes).
  50. A Detailed Look at Renewable Baseload Energy
    LazyTeenager, you forgot the bit asking how you intend to dispute the accuracy of the content of the reports. And since you bring up peer-reviewed papers, perhaps you have some in mind that you wish to challenge ? Do you have any evidence-based response at all ?

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