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Comments 68451 to 68500:

  1. Greenland has only lost a tiny fraction of its ice mass
    Moderator DB: Thank you for importing the graphic.
  2. (Fahrenheit) 451 ppm
    skept.fr#51: "The problem is not to say ‘it is not bad’" Look at the 'Most Used Climate Myths' in the upper left of every SkS page. 'It's not bad' is #3. "the ‘it could be worse than all you imagine’ strategy is pragmatically unfruitful for the last 10 years" And thus you would counsel abandonment of this strategy? "what models actually produce in their projections or IPCC reports actually acknowledge in their conclusions." AR4 is from 2007. Research and data continue to accumulate. Contexts which were 'projections' then are coming into focus (see Arctic ice melt faster than expected, for example). "If somebody tells me ‘we’re nearly sure Amazon will become a savanna before the end of the century’" Such focus on a specific prediction about a specific area and a specific time frame tends to make one blind to the larger issues. There are still those in the denial-world who focus on 'the Himalayas will be free of snow by 20xx' as a 'failure,' entirely missing the point that worldwide glaciers and snowpacks are dwindling before our eyes. This is not about predicting specific events; 'the trend's the thing.' "If SkS wants to be trusted, it’s necessary to rely strictly on what science says," Please provide an example where that is not the case; in this, the 'fire age' discussion is very clearly an extrapolation: What, then, will this new age, the one that follows our "green age," look like? ... I would suggest that we are now heading into a "fire age.". "Skepticism about 'doom and gloom' discourse..." Turn this premise around: Failure to discuss an increase in the frequency/intensity of extreme events would be gross negligence indeed.
  3. (Fahrenheit) 451 ppm
    angliss@12 "...that the cross correlations are so broad means that, as a function of lead and lag in a control system..." First, let me be perfectly clear that I am not interested in engaging in any arguments here. My response is intended only to clarify (and in one case amplify) what I meant, nothing more. I use the structure "x leads (or lags) y" only in terms of statistics of time series and never (or almost never) in direct relation to a dynamic system (or control system, as you call it). The time series data may result from observations of nature or may result from running a simulation model of a dynamic system. Within a dynamic system, I might speak of "delayed responses" and "time-lagged feedbacks" or "delayed feedbacks." I consider "simplistic" to be an inherent characteristic of a statistic. Simulation models of real dynamic systems are also "simplistic," some more so and some less so. I have had some small experience with simulation models of varying degrees of simplicity in various fields (demography, economics, politics, hydrology, urban and regional planning, etc.). I expand on my comment about discrimination being related to purpose, although it is off topic. I took a useful lesson from Anatol Rapoport about 1970. If we are interested in the biomass of small (not tiny, not large) mammals in our forest and want to know how it varies in time, then we trap some four-footed furries (FFFs), weigh them to determine their average mass, and conduct some surveys to estimate the total population of FFFs in our forest. We do this year after year and find that the FFF biomass seems to be at a stationary equilibrium. On the other hand, if we become interested in the life cycles of individual FFFs, then we may find it useful to discriminate between long-eared, short-tailed FFFs and short-eared, long-tailed FFFs. We may then find not a stationary equilibrium but a dynamic equilibrium (with an orbit in the phase space) and may even be led to discover a predator-prey relation between foxes and rabbits. The point is that how much (and what) we aggregate and how much (and what) we discriminate should bear a useful relation to our purpose in studying something and frequently has a direct impact on what we can discover. A small thought experiment: Suppose we have developed a perfect paleoclimate simulation model that with the proper initial data exactly reproduces all the available relevant time series data for the time period 799000 BC to 1000 AD. Will this model be able to correctly predict our future climate? I tend to doubt it. If we had such a model, then I think we would know more than we do now about some of the complex interactions we should take into acouunt. Nevertheless, we may be in an entirely new ball game with a new set of rules. Using the analogy with a business firm, we have taken a huge amount of long-term fixed assets (buried hydrocarbons, for example) and converted a small portion of them into current assets (plastics and crops, for example) and the vast majority into liquid assets in circulation (CO2 in the air and water). That may take us outside the applicability domain of our perfect paleoclimate model. Moreover, we appear to have started a long-term rapid warming episode with CO2 as the initiating GHG and with no large ice sheets in the NH. This also may take us outside the applicability domain of our perfect paleoclimate model. I frankly expect the next few thousand years to be very interesting with many new things to be learned about the climatology of Earth. We might even be able to observe what happens in a chaotic region of the system phase space.
  4. The Monckton Maneuver
    SirNubwub - You might be interested in the CO2 lags temperature - what does it mean thread. Monckton argues that paleo records showing CO2 lagging temperature mean that CO2 cannot be a cause of rising temperatures. He fails to understand (or perhaps, fails to indicate) that while CO2 has in the past acted as an amplifying feedback to other forcings (Milankovitch cycles), it has also acted as a forcing itself, bringing the Earth out of "snowball" conditions, and is currently acting as a forcing due to our producing 30B tons per year. Monckton has repeatedly and demonstrably misinterpreted science, misgraphed data in misleading fashion, quoted out of context, etc ("Mis - oh Mis!") - there's much more on the Monckton Myths pages. Personally, I find little to defend.
  5. The Monckton Maneuver
    Let's suppose you're right, SirNubWub. I haven't looked yet, but I will. You say, "If the editor is taking Monckton out of context in the one area that I recognize, I suspect that kind of treatment with the other quotes that are given." By the same logic, you should condemn Monckton, Watts, and many other so-called "skeptics" for their repeated failures of the same type. Are you willing to do that?
  6. The Monckton Maneuver
    In defense of Monckton: I do not know many of contexts of Monckton's statements, so I can't and won't defend them all. Perhaps he is a hack. But I do need to defend him on one issue that I recognized off the top of my head... The context of his statements about there being/not being a relationship between CO2 and temperature is being abused. At 4:50 in the first video, he says that there is a correlation, but this is taken out of context. A sentence is underlined stating that there is a correlation, but the NEXT sentence that is NOT underlined states that the correlation is not what is expected by the AGW proponents. Temperatures change in one direction first, then CO2 levels follow the change. Even Al Gore now recognizes that fact. Mr. Monckton appears to have done a typo and wrote 500 million years for this when it should have been 500,000 years of ice core data. The graph that I believe he is referring to is seen here: http://www.sahfos.ac.uk/climate%20encyclopaedia/co2.html Evidence that he just did a typo in the years includes that the quote shown discusses 4 interglacial periods. I think that would limit the timeframe to hundreds of thousands of years and not hundreds of millions of years in the past. This sloppiness that Monckton has with time frames is seen again at the 5:00 mark of the video where he says 600,000 years and the subtitle indicates he mean 600 million years. In the next scene where he is showing a graph where CO2 is graphed in black and the temperatures in blue, he is looking at data for a different time frame of 600 million years. The graph can be seen here: http://www.climateconversation.wordshine.co.nz/docs/012_no_more_global_warming.htm So, in this case, Monckton is seen to be a dweeb in not being able to keep his time frames correct. Maybe this would disqualify him as being a good source of info. But the video editor is seen to be dishonest in taking things out of context. (not underlining the next sentence that clarifies his statement) If the editor is taking Monckton out of context in the one area that I recognize, I suspect that kind of treatment with the other quotes that are given. I will need to look myself to be sure. But I will have to say this happens all to often when AGW proponents attack skeptics.
  7. Greenland has only lost a tiny fraction of its ice mass
    The article referenced by John Russell #11 is based on “2010 Spike In Greenland Ice Loss Lifted Bedrock, GPS Reveals” posted on the Ohio State University (OSU) website. The OSU posting contains a graphic, “The 2010 Uplift Anomaly (green arrows), superimposed on a map of Greenland showing the 2010 Melting Day Anomaly (shaded in red)” which I have attempted to import into this posting, but alas to no avail. Perhaps on of the more technically capable moderators would be able to do so.
    Response:

    [DB] Try this:

    Click to enlarge

    [Source]

  8. Plimer vs Plimer: a one man contradiction
    re: survival of the species People say such things in the hope that they'll sound bold and optimistic, but the question isn't of survival of a species. What a terrible criterion. "Civilization may founder. Millions or billions may perish, but if enough hominids survive the destruction, well, keep up the good work. Carry on. As you were. Don't tax the carbon." Loons. We're surrounded by loons.
  9. (Fahrenheit) 451 ppm
    #34 muoncounter : ‘Imagine the cost when those 'capacities' need to be developed and brought online at short notice because we sat around, pacified by those who claim 'its not bad,' and did nothing.’ The problem is not to say ‘it is not bad’ – just to observe that the ‘it could be worse than all you imagine’ strategy is pragmatically unfruitful for the last 10 years, beside the fact this strategy is usually biased with a selective presentation of what models actually produce in their projections or IPCC reports actually acknowledge in their conclusions. If somebody tells me ‘we’re nearly sure Amazon will become a savanna before the end of the century’ while science tells me ‘we don’t really know how Amazon will evolve during this century’, I’ve no reason to trust the first statement from an evidence-based perspective. And the same is true if you select just one or two publications among the whole literature. If SkS wants to be trusted, it’s necessary to rely strictly on what science says, including the mention of divergence among scientists teams and uncertainties in models, and to avoid ‘simplistic, inaccurate and indiscriminate view’ on climate change, to paraphrase Sphaerica. Skepticism about 'doom and gloom' discourse does not translate in approbation of optimistic statements (unfounded) and 'nothing-to-do' conclusion (undesirable). We fail to act seriously for now and we need to diagnose this failure, a misdiagnosis will just protract our collective failure. (Thanks for explanations about Climate Wizards). #35 Tom : ‘no national representative at Durban may deny the 2 degree C, 450 ppmv target, yet they have all just signed of on a deal that almost guarantees that we will exceed that target’ Yes but again, the good question is : why? I suggest here that the interpretation ‘climate negotiators do not fully think about the whole range of climate risks’ is wrong. They know the existence of low probability / high consequence events as we all know that. My hypothesis is that such events are not limited to climate change, but also of concern for economy and energy changes. #43 phila : ‘Foresight and planning, for instance. Unfortunately, these capacities tend to require accurate risk assessment, which is lacking on the "skeptical" side of the argument.’ That’s probably true if by ‘skeptic’ you mean ‘denier’. If not, it is false. An ‘accurate risk assessment’ is precisely what IPCC is committed to produce, so you must refer to IPCC reports. You produce a bad assessment if you prefer to rely selectively on a part of the literature or a particular hypothesis. That’s true for all domains, not just climate. You do not decide a health policy by focusing on the worst but unlikely hypothesis for a powerful emerging virus, because if you choose to do so, you forbid transport and trade so as to minimize human contacts, but you produce more harm than you avoid if your first hypothesis is wrong (or not the most probable when you have to decide in uncertain conditions). Further, a credible risk assessment includes the costs, benefits and uncertainties of the two terms of a choice. Everybody remember the large debates among specialists after the Stern report was published in 2006. Unfortunately, WG2 and WG3 are far less precise than WG1 when it comes to the evolution of human society under different boundary conditions for energy use. After all, human society is a complex system too and if we are rationally coherent, we should also fear the effects of brutal changes, poorly known ‘tipping points’, ‘black swans’, etc. The ‘grandeur nature’ experience of human history is a call for caution, isn’t it? For 20 years I read on climate and energy subjects, I’m really tired of the naive and over-optimistic ‘win-win’ discourses. If we want a climate decision, we need to first tell the truth to population about the difficulty of the task. For example, nearly all commentaries on Durban explain how sad it is not to extend immediately the Kyoto Protocol. But few recall that Kyoto Protocol did not achieve its very modest targets when grey energy from imports are considered. Do we really want to extend uncritically such a failure? It is totally irrational for me to proceed with such double discourses, wishful thinking and ignorance of reality. The most ambitious target (2 K / 450 ppm) decided at Copenhague and Cancun is supposed to be a 'victory'. But if it translates in a persistent blocking of climate diplomacy, that's just a defeat. The basic reality I observe is that we gave up more modest targets, like a progressive carbon tax on fossile producers or an immediate Green Fund for the third world, and wait for the 'ideal' solution that could never come, because many countries never ratified the Kyoto Protocol after 1997 and many still risk to act samely for the 2015 post-Kyoto Protocol. Again, the best is the enemy of the good and I tend to think the more radical postures are just the expression of impotence. (Sorry, most of my considerations are now OT here and I should have written them under the recent post about 2010 Carbon emissions. That's because the Sphaerica article coincided with the Durban conclusion, and it illustrates a type of perspective I can't agree with. Each element of this perspective is correct, with some conditional precisions, but IMO the agregate result is not convincing except for those who are already and intimely convinced that the worst issue is the most probable and that climate should the first concern in human affairs.)
  10. Galactic cosmic rays: Backing the wrong horse
    Hi Eric @60 I found this very interesting On infrequent occasions when the Platteville, Colorado, 10-MW radio transmitter matched the F region peak plasma frequency, intence localized sporadic E layers occured at low altitudes (95 km) Here is the link to the full artical http://www.ngdc.noaa.gov/stp/IONO/Dynasonde/images/HeatPrecip.pdf I started here, got me interested when looking at charged particals (free electrom formation) Ionespheric Heating http://www.ngdc.noaa.gov/stp/IONO/Dynasonde/SpEatHeating.htm
  11. (Fahrenheit) 451 ppm
    Thank you, DrTsk@47. Now I know and will try to remember.
  12. (Fahrenheit) 451 ppm
    skept.fr@14 "...there was a lag too between temperature rise and CH4 rise... Does Byalko refer to other paleoclimatic works for justifying that CH4 rise precede the temperature or is synchronous with it?" No, Byalko does not refer to other paleoclimatic to justify CH4 leading temperature. This was a result of a statistical analysis of the time series data, for which he cites two works (also cited by Konijnendijk et al. 2011): Loulergue, L., Parrenin, F., Blunier, T., Barnola, J.-M., Spahni, R., Schilt, A., Raisbeck, G., 25 and Chappellaz, J.: Orbital and millennial-scale features of atmospheric CH4 over the past 800,000 years, Nature, 453, 383–386, 2008. Luthi, D., Floch, M. L., Bereiter, B., Blunier, T., Barnola, J. M., Siegenthaler, U., Raynaud, D., Jouzel, J., Fischer, H., Kawamura, K., and Stocker, T. F.: High-resolution carbon dioxide concentration record 650 000–800 000 years before present, Nature, 453, 379–382, 2008. Byalko does propose a hypothesis concerning benthic methane hydrates as the source of the initial CH4 increase. I won't go into details of the mechanism he proposes to account for the statistical results. Links to English and German translations of Byalko's 2009 paper are given in #46 above. Regarding Delmotte et al. 2004, I think the time series data available to Byalko are more recent, have a higher precision, and cover a longer period of time. Regarding Konijnendijk et al. 2011, which is more recent than Byalko's 2009 paper, it seems to me that they were concerned primarily with developing and testing a model. From a cursory review of their paper, it seems to me that they speak about accounting for an observed lag of CH4 concentration behind the orbital forcing (not an observed lag of CH4 behind global temperature). I quote from their abstract: "Tropical temperature and global vegetation are found to be the dominant controls for global CH4 emissions and thus atmospheric concentrations." It should be noted this finding is in terms of their model and is not a conclusion about the statistical properties of the ice core data. In the summary, they write: "We have simulated wetland CH4 emissions over the last 650 000 yrs using a simple wetland distribution and CH4 emissions model coupled off-line to the atmosphere-ocean-vegetation climate model CLIMBER-2. The resulting simulated global emissions show a close similarity to the measured EDC-3 timeseries of atmospheric CH4 concentrations, both in spectra and in lags with respect to the orbital forcing." Finally, I note that in Fig. 4 (p. 71 in Konijnendijk et al. 2011), GHG concentration is shown in the red curve without distinguishing CO2 (in ppm) and CH4 (in ppb). It appears to my eye that this red (forcing) curve indeed lags the resulting emission temperature curve at the bottom. Although CH4 is a more powerful GHG than CO2, the three orders of magnitude difference in the unit of measure means that CO2 predominates in the green house effect with the values found in the ice core data.
  13. (Fahrenheit) 451 ppm
    BillEverett@46: Thanks for translating that paper and making it available. He does think that the methane is mostly benthic. According to Byalko, its release starts the warming (it could be a D-O event that starts the methane release, though he also mentions the speculation about the Clovis 'comet'). Oxidation of the methane doesn't produce enough CO2 by itself, so the CO2 comes from elsewhere - ocean warming, maybe. But he does seem to be taking the time lags he gets seriously.
  14. Global carbon emissions reach record 10 billion tonnes - threatening two degree target
    The Salon article referenced in my prior post is based on a new study, “Bankrolling Climate Change,“ produced by the environment organization urgewald from Germany, the social and environmental justice organizations groundwork and Earthlife Africa from South Africa, and the international NGO network BankTracka. “Bankrolling Climate Change” presents new research on the portfolios of 93 of the world’s leading banks. It examines their lending for the coal industry, the prime source of global CO2 emissions. It provides the first comprehensive climate ranking for financial institutions and identifies the top “climate killers” in the banking world. By naming and shaming these banks, the study sponsors hope to set the stage for a race to the top, where banks compete with each other to clean up their portfolios and stop financing investments which are pushing our climate over the brink.
  15. (Fahrenheit) 451 ppm
    BillEveret. Traditionally gas concentration ppm are volume or mole based. Therefore 400 ppb of CH4 give 400 ppb CO2. At the initial stages methane is equivalent to multiples of CO2 (x10?) and then it oxidizes to CO2 via several radical pathways reaacting with O2 and other oxidizers.
  16. Global carbon emissions reach record 10 billion tonnes - threatening two degree target
    One of the worst companies in the mining sector is Coal India. It is the largest coal mining company in the world in terms of production, and almost every problem connected with the industry you find in this company. That includes use of child laborers (which is against the law in India) and huge environmental problems, including underground coal fires in a heavily populated area. People are constantly confronted with carbon monoxide and huge volumes of toxic fumes. At the same time, you have Bank of America, Citi, Morgan Stanley and Deutsche Bank who organized an IPO for Coal India. They helped craft the prospectus for the IPO, which in 500 pages doesn’t mention the word “environment” or “climate change.” Source: “The Wall Street-climate change connection” Salon, Dec 10, 2011 To access this informative article, click here.
  17. (Fahrenheit) 451 ppm
    Jsquared@11: "Byalko is suggesting that oxidation of methane is what causes the CO2 to increase...methane causes the temp rise, and produces CO2 when it oxidizes, raising the temp still more... Am I interpreting him correctly?" First a caveat: I am not any kind of scientist. Therefore, if I incorrectly state some physics or chemistry, etc., I sincerely hope a more knowledgeable person will correct me. Basically, I think Byalko suggests that oxidation of methane contributes to the CO2 increase. Thinking about it, if I take 400 ppb of CH4, assume an approximate mass value of CH4 to be 16, oxidize it in a chemical reaction CH4 + 2 O2 => CO2 + 2 H20, and assume an approximate mass value of CO2 to be 44, then I find that 400 ppb of CH4 oxidizes to 1100 ppb of CO2 or 1.1 ppm CO2. This is obviously much less than the 100 to 200 ppm increase that ultimately occurs. Because I have seen estimates that CH4 is a more powerful GHG than CO2, ranging from 20 to 30 times more powerful, I would expect that conversion of CH4 to CO2 would reduce the warming effect. On the other hand, I have seen estimates of the half-life of CH4 in the atmosphere on the order of a decade and estimates of the half-life of CO2 in the atmosphere on the order of a century or more. The picture I have is that for some time on the order of thousands of years CH4 was added to the atmosphere faster than it was oxidized to CO2 and the CO2 resulting from this oxidation accumulated in the atmosphere because CO2 was being "scrubbed" by photosynthesis, etc., more slowly than it was being added. Moreover, rising temperatures resulted in release of CO2 from the oceans (the equilibrium concentration of CO2 in water is higher at lower temperatures -- I think this is why I cool the champagne in the refrigerator before midnight on 31 December). Altogether, we have a complex dynamic system. I googled for the English translation of Byalko's paper (I knew such a translation existed but didn't know if it was available) and found it on the web. I also found that there is also a German translation.
  18. Galactic cosmic rays: Backing the wrong horse
    scaddenp, except for perhaps a partial explanation for the LIA, I have not found convincing evidence of a cosmic ray effect on modern climate (i.e. late 20th century warming) skywatcher, conditions are different enough during glaciation to have a no GAT response to a large influx of cosmic rays and other coincidental effects. Life which can be killed off by possible coincidental solar flares would be different and restricted; there would be much drier air for less cloud formation; and there would be a lot more dust prior the event for nuclei so the event would not add much.
  19. Does model uncertainty exagerate global warming projections?
    Spelling error in the title: "exagerate" should be "exaggerate." (Better four years late than never?)
  20. Philippe Chantreau at 18:01 PM on 12 December 2011
    Plimer vs Plimer: a one man contradiction
    Mat L, what is the context on these? Does it include rock weathering, time scales, etc? As unlikely as it is, (pretty much impossible in fact) I would not be surprised if Plimer made the argument that, even if all the crust' carbon was released in the atmosphere (and that would be 11 times the quantity currently present according to him), some processes would remove the excess carbon so that atmospheric concentration would remain only at twice pre-industrial levels. I have not read the book myself (and I will not spend money to acquire it), so I have to rely on others' accounts. Plimer has held a lot of undefensible positions on this but nonetheless any accusation of self contradiction must be carefully weighted. In Monckton's case, it is obvious that he says whatever sounds plausible at the moment to meet the need of the argument. With this particular Plimer's pearl, it could be part of an internally consistent form of reasoning; as removed from reality as it may be, it would still be more honest than Monckton's spur of the moments falsehoods.
  21. Plimer vs Plimer: a one man contradiction
    Mat L at #23. "Plimer B "The total amount in known fossil fuel could only produce 11 times the amount of CO2 in the atmosphere". I note from the book p325, prior to the quoted sentence, that Plimer states "In order to permanently double the the current level of CO2 in the atmosphere and keep the oceans and atmosphere balanced, the atmosphere needs to be supplied with 51 times the present amount of atmospheric CO2." He then follows with the comment "Unless we change the fundamental laws of of chemistry and change the way in which oceans work, humans do not have enough fossil fuel on Earth to permanently double the amount of CO2 in the atmosphere." Further to Johnny Vector comment at #20, Plimer is of the view that at current CO2 levels, the majority of the warming occurs in the first 100ppm and that any warming after that is too small to be significant. (You also need to read all of page 278!).
  22. (Fahrenheit) 451 ppm
    44, Tom, As frustrating as current times are, and as both malignant and foolish as I know people have historically been, I am confident that we'll hold CO2 levels well below 1000 ppm. The evidence will not only be incontrovertible, but down right painful in about 20 years. At that time, the effort to get off of fossil fuels will then cause as much harm as anything else, because we'll have to get off of it fast. And we'll have pushed things way too far, and we won't be able to get off of it fast enough. Transitioning far enough away from fossil fuels is going to take a half a century, at least. But I do believe events will conspire to prevent us from being so abysmally stupid that we get anywhere near quadruple digit CO2. Unfortunately, I also believe that much lower levels are every bit as dangerous. Perhaps not Great Dying dangerous, but too dangerous to think about for too long.
  23. Global carbon emissions reach record 10 billion tonnes - threatening two degree target
    Solutions interalia: - 16% contributable to products used in the rich countries --> provide renewable energy technology at a price level of base-load power and add the difference in the price of the products. Consumer wise: if I have to pay for some carbon tax which goes I do not know or pay that same amount into a product where I do know. - China, India etc. can demand from any foreign operator that it has to supply xx% of its energy from a renewable source. So it can demand at least 16%. - Most developing countries are not stuck into some 150 year old distribution system loaded with stranded costs. Please do not load those countries with that ill-fated type of systems. - Forget about CAPEX and view OPEX. With the rapid changing technology of today your capital is out date within 7 years. Implement modular sizeable and many more actions...
  24. (Fahrenheit) 451 ppm
    Sphaerica @39, being somewhat pessimistic after the Durban result, I'll point out that there are sufficient reserves of fossil fuels to raise the CO2 content of the atmosphere to 4600 ppmv, or about four doublings over pre-industrial levels. It is unrealistic to expect all that coal (primarily) to be mined in under a century, but atmospheric concentrations of 1000 ppmv are certainly on the cards by the end of this century. Current policy is relying on their being no tipping point on natural carbon emissions to avoid going from the disasterous (which current policy seems intent on locking in) to the catastrophic.
  25. Galactic cosmic rays: Backing the wrong horse
    Eric #54, not only is there not strong evidence for a YD/GCR link, there is no evidence for a YD/GCR link. Your saying so does not count as evidence. We have a very plausible mechanism in place for the observed changes of C14 and of regional cooling, in the form of changes in oceanic ventilation driving changes in delta C14. Changes in oceanic circulation conveniently also help explain the see-saw effects between SH and NH cold periods (noted by scaddenp in #55). Why invent a cause that as yet has no connecting driving mechanism, and fails to explain all the evidence? The failure to explain the Laschamp anomaly is still not a help to your thinking. Why would it have no effect during a glacial phase? And you certainly cannot have any timelag (your #48), given that the few proposed (yet not demonstrated) mechanisms for a GCR-climate connection require it to be immediate.
  26. (Fahrenheit) 451 ppm
    skeptic.fr: "it is not unthinkable to imagine that there are adaptative capacities" Yeah. Foresight and planning, for instance. Unfortunately, these capacities tend to require accurate risk assessment, which is lacking on the "skeptical" side of the argument.
  27. (Fahrenheit) 451 ppm
    Sphaerica: you're absolutely right that the world was a different place; I was thinking conditions that existed back then (e.g. weaker sun as you pointed out, plus no mass deforestation) would mean CO2 feedbacks weren't as strong as they are now. As if permafrost melting wasn't bad enough, we have ozone damage to worry about too:
    High ozone concentrations can affect not only plant growth, but soil fertility. Plants exposed to low ozone concentrations normally metabolize a certain amount of carbon dioxide. They send carbon to their roots, and then to the surrounding soil. Microbes in the soil make use of this carbon. Plants that are exposed to high ozone concentrations metabolize less carbon dioxide, so less carbon is available in the soil, and fewer soil microbes grow and thrive. Microbial activities that result in soil enrichment and carbon processing decrease, with the result that soil fertility diminishes.
    Pretty obvious vicious circle there :( More fossil fuel burning = more smog/ozone = damaged plant life that can't scrub as much CO2 = even worse positive feedbacks That's what I'm trying to figure out; are we on a course where all the natural carbon sinks might very well get killed off, thus leading to a Venus-style runaway greenhouse effect.
  28. (Fahrenheit) 451 ppm
    Pixeldust - the Permian-Triassic Extinction is ill-suited as an analogue for our future, because it happened so much slower (1-2 billion tons of CO2 per year, versus over 30 billion tons today from fossil fuel-burning). So the current rate of CO2 release is 15 to 30 times faster than the Great Dying. See: Ocean Acidification in Deep Time -Kump (2010) But that's not quite an apples-to-apples comparison, because even though the rate of change was slower, it carried on for a very long time, and we don't have enough fossil fuels to replicate that experiment. The greatest problem is the speed of change is so great, that many plants and animals we depend upon for our survival will probably become extinct, before have they chance to adapt. Certainly that's what the paleo record tells us, rapid injections of atmospheric CO2 (and by rapid I mean slower than today's rate) lead to widespread extinction.
  29. Pete Dunkelberg at 14:51 PM on 12 December 2011
    (Fahrenheit) 451 ppm
    This new study looks at bunched precipitation on a very fine scale. This one is broad scaled. The bunched precipitation pattern seems to repeat itself from the global scale down to very small events, almost analogous to a fractal.
  30. Plimer vs Plimer: a one man contradiction
    More for the Mill: On the burning of fossil fuels: Plimer A: “If humans burned all the fossil fuels on Earth, the atmospheric CO2 content would not even double”. Heaven and Earth, p293 Plimer B: “The total amount of carbon in known fossil fuel could only produce 11 times the amount of CO2 in the atmosphere”. Heaven and Earth, p325
  31. (Fahrenheit) 451 ppm
    36, PixelDust, I wouldn't go nearly that far. Again, to some extent it is apples and oranges. The world was a vastly different place back then, with one giant land mass, different ocean circulation patterns, a sun that was slightly weaker, etc. But I don't think we could ever reach 2000 ppm. Civilization wouldn't last that long, even if we found enough coal and gas to burn. The one thing I do find interesting is that CO2 in the Triassic was basically 275 ppm (from what I've found... I'm not that familiar with the period). CO2 for that event seemingly increased to 2000 ppm. That's a factor or 7.78 times. The temperature increase was estimated at 8˚C. 8=Tsensitivitylog2(2000/275) gives a climate sensitivity of 2.79˚C... or roughly 3˚C. Funny how that number keeps coming up over and over again.
  32. Pete Dunkelberg at 14:04 PM on 12 December 2011
    (Fahrenheit) 451 ppm
    skept.fr @ 27 "...winners and losers in precipitation trends." That Climate Wizard map looks rather mild compared to this. Whatever the extent of drought in coming decades, considering drought alone overlooks global bunched precipitation. A few paper are linked here and there are more. The weather that seems to be coming at us is floods some places, (some keys to floods and excessive rain are here) drought some places and bunched precipitation (also not good for agriculture) in between. Winners may be scarce.
  33. Galactic cosmic rays: Backing the wrong horse
    Hmm, why would cooling start in SH and then end as NH goes cold? (Actually not an uncommon pattern). I think other explanation other than GCR remain a great deal more plausible. Also, the real question of interest, is whether the forces at play in these events could be still impacting modern climate. Very difficult to find evidence for that.
  34. Galactic cosmic rays: Backing the wrong horse
    Scaddenp, the difference between hemispheres reduces one of the explanations of the C14 spikes (suggested in 51 and 52). The GCR effects could vary depending on the amount of ocean versus land, but I have no information for or against that idea. Muoncounter no possible connection between magnetic reversals and solar inputs that I can imagine. The PETM magnetic reversal was isolated and probably just coincidence (see the chart in my post 53. Certainly the link from magnetic field reversals to climate is going to be very tenuous due to the rather short duration of the change as you point out.
  35. Galactic cosmic rays: Backing the wrong horse
    Eric#53: "in a very rough sense, more reversals (with coincident weakening) allows more GCR and more cooling." A geomagnetic reversal includes a period of time (decades? hundreds of years?) when the field is of very low intensity. If the GCR story is to be believed, these must be times of high GCR flux, cloud formation and significant cooling. However, Lee and Kodama 2009: report high-precision records of a magnetic reversal event at the Paleocene-Eocene thermal maximum (PETM), a cataclysmic global warming event initiated at 55.0 Ma. But that's the earth's magnetic field; GCR orthodoxy involves solar output - those FDs that are supposed to be harbingers of fewer clouds. Is there a connection between geomagnetic reversals and the solar wind?
  36. Galactic cosmic rays: Backing the wrong horse
    Because of the importance of C14 to dating, the isotope and its interactions have been very closely studied for a long time. Be10 is nowhere near as well understood and I have colleagues working on hard on it. If GCR is important to YD, then why is it decoupled between hemispheres? For the corresponding SH events, you have ACR (Antarctic cold reversal) started before YD and finishing as YD gets going. This is fascinating area of study but the collected evidence from both hemispheres I think supports the idea that these events, associated with deglaciation, have there origin in ice sheet dynamics and interactions with the THC rather than some external forcing.
  37. Pete Dunkelberg at 13:17 PM on 12 December 2011
    (Fahrenheit) 451 ppm
    I hate to add to the gloom but given that we are staying on a very high emissions schedule so far and given that we can't change everything in less than decades even when we really decide we must, CO2 may go to 600 ppm or more. This could start serious carbon feedbacks and bring PETM-like instability for a few million years.
  38. (Fahrenheit) 451 ppm
    For me, the biggest fear has been that we're duplicating the conditions that led to the Permian Extinction Event: Smoking Gun: Greatest Extinction in History was a Volcanic, Coal fired, Greenhouse Event Sphaerica, how would that fit in with your analysis here? Are the Siberian Traps eruptions the closest natural analogy to modern fossil fuel combustion? If so, assuming worst-case scenarios (human CO2 emissions continuing to grow, Arctic belching methane at an ever-increasing rate, natural carbon sinks overwhelmed or turning to carbon source, etc), how soon could a new, Permian-esque mass extinction start? Apologies for lack of scientific precision in my question; I'm coming at this issue from a layperson's perspective
  39. Galactic cosmic rays: Backing the wrong horse
    Thanks for the clarification Sphaerica. CO2 being "not a control knob" for preindustrial has a couple exceptions that Tom pointed out on the other thread. There are times when it was in the past along with methane. Muoncounter and skywatcher, I agree that YD is not strong evidence, but more study is needed to determine the causes which AFAICT remain unknown. Another bit of evidence for a GCR knob is LIA cooling although it coincides with decreased TSI as well. I don't think the Laschamp event is a good test of GCR impact since we were in a glacial state which was probably a somewhat stable state.
  40. Galactic cosmic rays: Backing the wrong horse
    Tom, thanks for the comment. Yes, GCR's + or - do not result in positive forcing sufficient to exit the snowball state. GCR is definitely not the control knob, but one of several. The main theory seems to be cooling from high GCR's. It seems to me a more precise theory is that high GCR's retard or preclude warming by other means. Looking at the earth's magnetic reversals, http://upload.wikimedia.org/wikipedia/en/c/c0/Geomagnetic_polarity_0-169_Ma.svg in a very rough sense, more reversals (with coincident weakening) allows more GCR and more cooling. Obviously earth's reversals are a small part of the modulation of GCR so not a strong connection. I was unaware of the complexities of Be10 and I am sure there are some for C14 as well. The correlation of low Be10 measurements with higher rainfall could explain some of the Mercurio chart and is worth looking into further.
  41. Galactic cosmic rays: Backing the wrong horse
    Eric#48: The last sentence of the Laken abstract sounds like the standard qualifier, YMMV, to me. What significance do you see in it? "A control knob need not be overwhelming and instant and this GCR link would be offset by oceanic cycles and other weather." If this so-called control knob is so easily offset, then why maintain that it is a 'control' of any kind? At best, it is a fine tuner. But you cannot suggest that a GCR-cloud mechanism, if real, has some sort of lag. Ionization and cloud condensation either makes clouds or it doesn't. "A large decrease in GCR flux appears necessary for deglaciation" Again, where is the evidence for this declarative statement? The YD is not without its own complexities, as reported by Hughen et al 2000: the Younger Dryas 14C anomaly, which is by far the largest of the last 15,000 years, is not matched in amplitude by corresponding atmospheric 10Be concentration estimates. Thus, available 10Be data do not support the interpretation of the Younger Dryas 14C anomaly as solely or mostly due to increased production. In order to promote the speculative GCR-climate connection into a 'control knob,' you'll need a lot more evidence, a mechanism and most critically, an explanation for the climatological non-event at the Laschamp GCR peak.
  42. Galactic cosmic rays: Backing the wrong horse
    Eric, you're making suggestions that GCRs drive deglaciation and the Younger Dryas, yet these are not supported by evidence or your references. What is your support for GCRs being necessary for deglaciation in our current geographic configuration? Why, when this configuration has lasted throughout the Quaternary, are glaciations and deglaciations timed with orbital forcing? An again, why does any noticed correlation necessitate a causal connection? Your assertion about GCRs and the Younger Dryas is unsupported by the Hughen et al 2004 article from which you take your graph:
    "Peaks in 14C are also reconstructed at 40 and 29 cal. ka B.P. and previously reported at 12 cal. ka B.P. (13), coincident with Heinrich events H4, H3, and H0 (Younger Dryas), respectively (35). These events may also have been associated with unusually large perturbations in ocean ventilation and sea-ice cover explaining “anomalously” elevated 14C at those times (23, 36)."
    The main hypothesis is that the radiocarbon plateaux are driven by oceanic circulation changes (Hughen et al 2000 is ref 13 in the above quote). There is also doubt about the Cariaco radiocarbon spike - Muscheler et al 2008 suggest that upper ocean changes in the Cariaco basin itself influence the record.
  43. Galactic cosmic rays: Backing the wrong horse
    48, Eric, For the record, I was saying the same thing that you are, that in those cases CO2 was an amplifier tied to temperature itself, and not a control knob. It's fairly well accepted that the trigger for the event was a change in orbital configuration that changed not TSI but simply the duration and strength of Northern Hemisphere summers, which in turn triggered the retreat of the ice sheets, reflecting back less sunlight (and in that way causing a lower TSI). The main issue in the glacial termination debate is the main mechanism for the abrupt surge in methane and carbon dioxide that let the whole thing get from "there" to "here." I should point out, too, that in this sense I'm simply using the term "control knob" in a different sense that Dr. Alley. It's still a "knob" in that it affects temperatures, but it wasn't a knob before 1751 because no intelligent civilization had until then been able to change CO2 in the atmosphere. From that perspective, no, it wasn't a control then, but it is now.
  44. Galactic cosmic rays: Backing the wrong horse
    Eric (skeptic), a few thoughts that I cannot follow up properly at the moment: 1) Shaviv's temperature reconstruction is almost certainly wrong, both because it has been shown to not compensate for the effects of changing ocean pH, and because it is incompatible with the record of Earth's cryosphere. The oxygen 18 record from Royer et al, 2004, essentially reproduced below, although from a different paper is Shaviv's record as corrected for pH. Further, if Shaviv where correct, the absence of glaciation around 200 and 450 million years ago is astonishing, given the temperatures relative to current global temperatures. 2) Further, given a GCR connection to climate change, it seems unlikely that the early Earth would ever exit a snowball state. Essentially, the early Earth had 70% of the current TSI. That also meant a weaker magnetic field, and hence more GCM reaching the Earth. The logical conclusion with both a weaker sun and higher cloud albedo due to GCM's is that a snow ball state would have been a permanent feature of the Earth's climate until at least the last 200 million years. 3) Finally, I am uncertain that you can simply assume Be10 cannot be a dependent variable for climate. Specifically, Be10 is formed by spalliation from Oxygen or Nitrogen. It is then washed from the atmosphere in solution. When a particular sediment dries, the Be10 is left behind in proportion to its concentration in the water. Intuitively, there are then two controlls on Be10 concentration. The rate of formation, which determines concentration in the atmosphere; and the rate of rainfall. Larger quantities of rainfall, by washing the Be10 out of the atmosphere more frequently, and with a larger volume of water would result in a lower concentration of Be10 in the water, and hence in the resulting sediment. Alternatively, dry times such as the last glacial, would result in higher Be10 concentrations. This is just a suggestion by me, and may be entirely wrong. It would, however, neatly explain the correlation shown by Mercurio, and explain why Be10 concentrations do not always vary with fluctuations in the Earth's magnetic field (as indeed, is shown by Mercurio during the last glacial), and also why Be10 and C14 concentrations do not always correlate.
  45. Galactic cosmic rays: Backing the wrong horse
    Muoncounter, the end of the abstract says "However, we note the detectability of any potential links is strongly constrained by cloud variability." A control knob need not be overwhelming and instant and this GCR link would be offset by oceanic cycles and other weather. You asked "Are you suggesting here that a change in GCR flux is necessary to initiate deglaciation? If so, why - and on what evidence?" A large decrease in GCR flux appears necessary for deglaciation in the current geographic configuration, but a spike can throw it off e.g. in the Younger Dryas (13ky bp) I admit this is not a particularly strong event, but I don't think it is pure coincidence that the 14C spiked then Y.D. took place.
    (from http://alliance.la.asu.edu/temporary/students/Phil/Hughen.pdf) Skywatcher, the GCR spike shown in #29 took place in full glaciation so I would not expect a GAT response. My purpose in resurrecting this thread was to respond to the claim in Spharican's latest post "It took an increase of 105 ppm, or a factor of 1.6, to get us from an "ice age" into the world in which we currently not only live, but thrive" As I said there, it took more than CO2, it required a control knob, with the 1.6x CO2 functioning as an amplifier. The control knob could be TSI, and not GCR as there is considerable overlap in their effects.
  46. (Fahrenheit) 451 ppm
    skept.fr @20, no national representative at Durban may deny the 2 degree C, 450 ppmv target, yet they have all just signed of on a deal that almost guarantees that we will exceed that target.
  47. (Fahrenheit) 451 ppm
    skept.fr#32: Withlock deals with fire's role as an ecological process; re-defining fire-regime triangles has nothing to do with this discussion. Customizing the settings on climatewizard.org is straightforward. One of the options in a drop-down menu under 'Measurement' near the top is seasonal, monthly or annual. "For 'winners' and 'losers', replace these undue notions by there will be 'regions with more/less precipitation and greening'." 'Winners' and 'losers' were your choice of words; their replacement with gentler sounding euphemisms is mere semantics. "many countries depend on regional and global trade rather than sel-sufficiency." That's the point - the global interdependency of the world food supply is exactly why there can be no winners. "it is not unthinkable to imagine that there are adaptative capacities" Imagine the cost when those 'capacities' need to be developed and brought online at short notice because we sat around, pacified by those who claim 'its not bad,' and did nothing. Seems like we've had this conversation before.
  48. (Fahrenheit) 451 ppm
    #30 scaddenp : I globally agree with you. AFIAK, UE negotiators accept the principle of 'common but differential responsibility' in AGW diplomacy. That's why the Kyoto Protocol or the 20-20-20 European climate plan are not bound to commitment by other parties, from Annex I or non-Annex I. And that's why the first, second and third world will not have the same reduction targets in an (hypothetical) 2015 agreement.
  49. (Fahrenheit) 451 ppm
    @28 muoncounter : "Other than the word 'fire' in the title, is there any relevance in the Withlock reference to this discussion?" Quite surprising, did you read the paper? In #21, you speak of climate change and fire correlation. Withlock et al 2010 have developments on weather/climate conditions of fire in climatic archives, but also on all factors influencing fire, including vegetation change. If you consider that as OT, then your #21 wat OT too. For 'winners' and 'losers', replace these undue notions by there will be 'regions with more/less precipitation and greening'. That was my initial point in #15, the idea that vegetation will regress globally does not seem to be supported by vegetation models coupled to AOGCMs. Don't understand what you mean by 'tweaking climate wizard settings a tad' and how you get summer (or any particular season) precipitation on this site. (For extreme events, I guess the recent SREX is the most updated reference of the expert view. There is just the SPM for the moment, where I read : "There is medium confidence that droughts will intensify in the 21 st century in some seasons and areas, due to reduced precipitation and/or increased evapotranspiration. This applies to regions including southern Europe and the Mediterranean region, central Europe, central North America, Central America and Mexico, northeast Brazil, and southern Africa. Elsewhere there is overall low confidence because of inconsistent projections of drought changes (dependent both on model and dryness index). Definitional issues, lack of observational data, and the inability of models to include all the factors that influence droughts preclude stronger confidence than medium in drought projections."). If feeding the world is "at risk" (for change in precipitation), I suppose the global primary productivity conditions in 2050 and 2100 is the most wanted information. Because even today there are deserts, droughts, etc. so agriculture adapts to changing conditions and moves if necessary, many countries depend on regional and global trade rather than sel-sufficiency. At least, it is not unthinkable to imagine that there are adaptative capacities in two or three generations (agriculture was different from now in 1970 or 1930). Conversely, feeding the world without directly or indirectly fossil-assisted technologies that sustained current productivity (mechanical engines, fertilizers, construction of irrigation and stockge systems, R&D biotechnology, etc.) is a challenge, and I'm quite surprised that nobody considers that there are some "risks" here too...
  50. (Fahrenheit) 451 ppm
    Sphaerica, this is the skeptic sight so I imagine one would be skeptical of post 26, but I have spent 40 years on it, and have a masters from UCI, so please consider it. May contact me at p*******y@gmail.com. I hope this is not breaking spam rules, if so please forgive me.
    Moderator Response: [Sph] E-mail address edited for privacy.

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