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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 74751 to 74800:

  1. Sea level rise is exaggerated
    # 174 Papy Your source has this interesting statement: In essence, we would like our GMSL time series to be a proxy for ocean water volume changes. In other words they aren't really measuring sea level anymore. They aren't measuring sea level relative to the center of the Earth, nor are they measuring sea level relative to the shore line. So, if I want to sea what sea level is relative to the center of the earth, I need to subtract the GIA from those last two data points. Indeed, that's what Colorado U said to do back in May when they announced that they were adding the GIA correction. They said: Simply subtract 0.3 mm/year if you prefer to not include the GIA correction. (Link) Why might you want to not include the GIA correction? If you wanted to know what sea level is and not ocean water volume.
  2. Heat from the Earth’s interior does not control climate
    Some bizarre claims there #14 Galileo. You claim the radioactive heating hypothesis is preposterous, yet don't tell us why? Apart from Sphaerica's excellent point, I might ask you a more philosophical question. If lightning strikes can start forest fires, does that mean that arsonists are incapable of starting forest fires? This is akin to your suggestion that the same single explanation should fully describe the interior states of all the planets in the Solar System. You compare Earth to Io, yet one is a planet orbited by a large moon, and the other is a moon orbiting closely to the most massive object apart from the Sun in the Solar System. Io's mass is 1.5% of the Earth's. The objects driving the tides are vastly different - Jupiter's mass is something like 26,000 times that of the Moon, and that mass is driving tides on Io at a similar distance to the lunar tides. Why would the internal processes necessarily have the same origin? Sadly, it's another bizarre claim to add to the increasing list.
  3. One-Sided 'Skepticism'
    Marcus, could you document that please?
  4. Sea level rise is exaggerated
    "Including the GIA correction has the effect of increasing previous estimates of the global mean sea level rate by 0.3 mm/yr. (Source) Doesn't this mean that, to illustrate the 2011 new releases GIA correction, you should have done exactly the opposite : let the blue line after 2011, and substract 0.3 mm/yr before ? But I agree that the influence of this correction should be discussed to determine if the nino variations are the only driver of the recent global sea level drop.
  5. Sea level rise is exaggerated
    I was curious about the history of the Sea Level Estimates published on the web by Colorado University. Here's the current estimate, 2011 release #2, of 3.2 mm/yr: I used The Internet Wayback Machine and searched on: [http://sealevel.colorado.edu/] [take me back] I found the following series of CU Sea Level Estimate pages: YYYY MM DD; Rel #; rate mm/yr 2004 02 15; rel 1; 2.8 2004 12 23; rel 4; 2.9 2006 04 10; rel 5; 2.9 2007 09 08; rel 2; 3.0 2007 04 27; rel 3; 3.2 2008 02 10; rel 2; 3.2 2008 09 08; rel 3; 3.2 2009 01 24; rel 4; 3.3 2009 11 02; rel 2; 3.2 2010 04 13; rel 4; 3.1 2011 01 08; rel 5; 3.1 2011 07 18; rel 1; 3.1 2011 07 19; rel 2; 3.2 So I plotted them all out: I added in red what the time line would have been if GIA hadn't been added starting in May of 2011
    Response:

    [DB] If you have a point with this exercise please be more transparent and just state it.  As it stands right now, you don't.

  6. Dessler Demolishes Three Crucial 'Skeptic' Myths
    jpat - responded on more appropriate thread. Check the papers in the intermediate section as well.
  7. CO2 lags temperature
    jpat - I do not believe so because the carbon-cycle feedbacks are from multiple sources, act over different time scales, (including a negative feedback - enchanced vegatation growth), as well as coupling with an albedo feedback. It is not obvious to me that the feedbacks should even be symmetrical. (Some like methane release versus methane storage are clearly not).It appears to me that you are thinking about this by analogy to a forced oscillator whereas a much more complex physical model is involved. More light on this should emerge from Ar5 models. However, the corollary of your question seems to imply that you think either: 1/ GHG do not cause warming - or 2/ the CO2 increase in atmosphere is causing warming rather than other way round. Both of these can be discounted from other evidence.
  8. Observations of Climate Change from Indigenous Alaskans
    I suppose there is a noticeable difference between -25C and -40C to those who live with and depend on frigid winters. The only time I experienced such temperatures was in 1950's in Igurka on the Ob river in northern Siberia. Never again!
  9. Heat from the Earth’s interior does not control climate
    Stu#16: "Bizarre claim ... Doug Cotton" I can't imagine how you could pick out just one bizarre claim, like identifying a single tree in that very large forest. For example, his geothermal gradient of 27 deg C/km puts the temperature at the outer core boundary at a mere 79700 C; why worry about an 1800% error? But sadly, that's not the most bizarre claim out we're hearing these days.
  10. Climate Communication: Making Science Heard and Understood
    Pirate, I think you need two things. First, the survey needs a purpose. Simply gathering information with no focus or objective is too open ended. Second, you talk about a before/after context, but this would require some intermediate step whose impact you are trying to evaluate. I would suggest settling on a specific purpose. Is it to find out how many blatant misconceptions most people have? To demonstrate to them how little they know, or how complex the science is, or how much scientists do know? How influenced they are by politics? What they learn from a new, surprising source of information? The second item -- the before/after effect -- is going to depend entirely on what it is that you expect to happen between the surveys, and as a result, that will define the content of your survey. I would actually suggest either writing a brief article (and submit it here for "peer review") or choosing a sampling of key articles from this site. Write a survey that can be given before and after reading the chosen articles, or one for before and a different one for after. Once that step is done, the content and phrasing of the survey will probably become obvious. Then you can execute it... give the survey, let the population do the reading, then repeat (or give the second) survey. I personally like the idea of a survey that highlights how much is known and certain in climate science, and what the sources of information are. I think most people would be surprised at how clever and accurate paleoclimate studies and observations are, and what we are able to infer accurately and unequivocally from them.
  11. Heat from the Earth’s interior does not control climate
    14, Galileo, You make some interesting assertions, but the actual science weighs against you. You say:
    So there you have it, the radioactive heating claim is preposterous.
    The following paper pertains to actual measurements detecting such a source of heat: Earth's heat budget: Clairvoyant geoneutrinos (Jun Korenaga, 2011)
    The quantity of heat generated by radioactive decay in Earth’s interior is controversial. Measurements of geoneutrinos emitted from the mantle during this decay indicate that this source contributes only about half of Earth's total outgoing heat flux.
    You said:
    ...this is not good since if a hypothesis cannot be tested then it does not qualify as being a scientific hypothesis.
    And yet it has been tested. I'm not going to argue all of the details of a fairly theoretical aspect of science that doesn't entirely interest me, but it is one in which real scientists are now developing ways to actually observe and measure. I'm afraid your rather lordly and holy dismissal of the science was a bit premature.
  12. Climate Communication: Making Science Heard and Understood
    Yes, please, tell us what you want to measure, Pirate. Is it attitudes? Knowledge of theory? Fundamentals of physics? Mitigation?
  13. Positive feedback means runaway warming
    jpat - A strictly electronic analogy will not work well with respect to the climate system. To some extent a transistor or op amp would correspond, but transistors are too non-linear. An operational amplifier could be used to build a corresponding circuit, with the Stephan-Boltzmann law providing the negative feedback, but not a bare op-amp. The S-B law indicates that thermal radiation to space scales as T^4 (in Kelvin), and means that excess energy accumulation in the climate, simply by heating/cooling the Earth, will rebalance the input/output levels. That's your negative feedback. There are fast energy state response elements (water vapor, clouds), slow response elements (ocean CO2, albedo from ice coverage, vegetation), and over and above this the forcings that drive those feedback items. In the ice age cycles a small amount of insolation variation (orbital changes shifting land/ocean exposure and polar insolation/albedo changes) acted as a forcing, with the temperature sensitive elements responding at various delays. Currently we are introducing a direct forcing with GHG's, and should expect to see water vapor levels, albedo, vegetation, and in fact CO2 levels from ocean solubility respond to the initial forcing with their own changes. All of these - forcings and feedbacks - act as throttles on the flow of energy from the sun into the climate and back out again, with rates dependent on the various states, gas concentrations, albedo, etc.
  14. Positive feedback means runaway warming
    I guess my attempt at input a schematic got mangled by the html processor (block tags doesn't seem to work). KH - I posted before I saw your response. I take your point but am still struggling to understand how feedback amplifies the Milankovitch cycles. The system has to do real work, melting ice, heating the oceans etc. and I thought the argument was the system does more work with feedback than it could do without. That sounds like power amplification to me but I'll come back after I read up some more.
  15. Positive feedback means runaway warming
    rf -----^v---- ri | | -^v----*----|+\__| ? Vin --|-/ | _|_ |______| \ / Consider the circuit above. The op-amp is configured for unity gain. The feedback "gain" = ri/(ri + rf) < 1 and the feedback is positive. Since the forward gain is unity, the open loop gain (referred to as "gain" in #37) = feedback attenuation < 1. The claim in #37 is that this circuit will amplify. Not so much. The inverting input of the op-amp is wired to the output (Vo). The op-amp is ideal so the non-inverting voltage (v+) is equal to the inverting input voltage (v-) So Vo = v+ = v-. This means the voltage drop across rf = 0 which by Ohm's law means the current through rf (Irf) =0. But Irf = Iri. Thus the voltage drop across ri = 0. Thus Vo = Vi. The gain of this circuit is unity. Now suppose the op-amp is configured for a gain of 2 and the feedback divide ratio < .5 (again, so that gain as defined in #37 < 1). At first blush it appears capable of amplification. Now add the stability constraint that the input impedance > 0. We find that for stability, ri > rf. The open loop gain for the circuit can be shown to be 2-rf/ri which again must be <= 1 for stability. This doesn't disprove anything but rather shows that the feedback gain equation is subject to boundary conditions including conservation of energy. I really wonder whether one could devise a physical system capable of doing work using the formulation provided by KR.
  16. Heat from the Earth’s interior does not control climate
    Bizarre claim on Doug Cotton's website: "It is the heat flow from the core of the Earth that maintains a "base" temperature simply because the underground conduction rate is far slower than the rate of convection for warm air rising in the atmosphere. Life as we know it would not exist on this planet if the temperature gradient caused by the heat flowing from the core were such that the mean "break out" temperature at the surface were not something like 9 deg.C give or take a few degrees." I would put it Doug Cotton that he should consider what the surface temperature of the Earth would be if it had the same solar insolation and same atmosphere, but didn't have a hot centre. More to the point, he should calculate what the surface temperature would be if you were able to turn off the sun and let the temperature equilibriate...
  17. One-Sided 'Skepticism'
    Hmmm, I recently recall that Watts & his cohorts recently laid into the head of the BEST project, & fellow skeptic, Professor Muller with a vicious ad hominem attack-after his preliminary results thoroughly debunked Watts' claims of unreliable surface station data. This after Watts had spent more than a month singing Muller's praises, & claiming he'd accept the outcome of the study, no matter what those results would be. If Pielke were in any way consistent, he'd surely launch a scathing attack on Watts for this behaviour. However, if his comments here & at his own website are anything to go by, Pielke is only interesting in maintaining solidarity amongst his fellow skeptics, not with ensuring that scientists are free from ad hominem attacks.
  18. Positive feedback means runaway warming
    jpat - Not power amplification, that's a misunderstanding of the system. GHG's act as a throttle controlling energy flow out of the Earth climate, all said energy coming from the sun. Input energy inevitably gets dumped to space, the question is in what thresholds are in place in the mid-point of the system, driving internal energy levels so that the throughput can occur. You seem to be treating this as a limited system, rather than an open system with energy flows. I suggest more reading on your part. I would point you to The Discovery of Global Warming as a starting point. Not a passive system - a dynamic system. That's a serious error in viewpoint.
  19. Heat from the Earth’s interior does not control climate
    From Galileo's website: "When scaling, the ratio between the area and volume changes: the area of my kite scaled by a factor of three squared while the volume scaled by a factor of three cubed. I was astonished that the Square-Cube Law was not covered in my grade school science class." Someone was asleep in math class ...
  20. Observations of Climate Change from Indigenous Alaskans
    Thanks for posting this, John. I'd skimmed over it when it first came out & had neglected to get back to it with the proper justice and diligence. OT: ptarmigan always reminded me of tarmangani...
  21. One-Sided 'Skepticism'
    Basically, Dr Pielke was unwilling to address the real issue at hand, which was whether his colleague's had made scientific blunders and mistatements, and whether characterizing them as such etc was therefore justified (colorful language aside). Now he seems to be complaining about being held to that standard. Given that he largely seemed interested in directing attention away from the central topic, I can see why he would complain about SkSs organization and moderation, which is explcicitly designed to avoid exactly that. Maybe he prevaricated out of a sense of loyalty because he knew Christy's and Spencer's statements could not be directly supported. Such loyalty may be admirable, but it doesn't change the facts.
  22. Heat from the Earth’s interior does not control climate
    It looks like a really nice article presentation. However I have to protest the promotion of the idea that radioactive material heats the interior of the Earth. I mean, how do you go about testing this hypothesis? The answer is you cannot. No one knows what is in the center of the Earth. Maybe some people think that this is great since without a means of testing a hypothesis then no one can prove it wrong. But actually this is not good since if a hypothesis cannot be tested then it does not qualify as being a scientific hypothesis. To clarify why this is wrong let me give an example of another untestable hypothesis such as ‘all good people go to heaven after they die’. Untestable hypotheses are not actually science. Even without direct evidence, there is still plenty of indirect evidence that strongly weighs in against radioactive heating being correct. For example, if the entire interior of the 4.6 billion year old Earth was filled with radioactive potassium this still would not produce enough heat to account for the heat coming from the Earth’s interior. So there you have it, the radioactive heating claim is preposterous. It is only because so few people are capable of doing the math and / or willing to take the time to do it that the weakness of the radioactive heating claim is not apparent to everyone. No doubt it makes us feel good to have answers to life’s questions, but quickly filling every mystery with the first answer that ‘sounds right’ is counterproductive since it brings an end to science inquire. If either one of these propose answers to what heats the Earth’s interior were correct, then they should bring us greater insight into understand our Earth and our solar system. But of course they do not; their purpose is to just to explain away the paradox without concern if the answer is right or wrong. Obviously they are wrong since astronomers have rejected them in their efforts to explain Jupiter’s moon Io is being heated from within. In all likelihood, an answer that explains the heating of one heavenly body should be general such that it works for all the planets and moons of our solar system. Astronomers say that tidal heating is what heats Io’s interior. And here is the best part. It can be shown that tidal heating alone can explain the interior heating of all the planets and moons throughout our solar system. The theory correctly predicts which planets should be hot and which ones should not. As an extra bonus, the theory correctly predicts the density of these objects. For example, the Earth has the highest density of all the planets in our solar system due to close proximity of the Moon producing a disproportionally large amount of tidal heating within the Earth. One of the biggest problems with science today is that so many people blindly follow science dogma rather than thinking about the new progressive ideas that allow us to understand our reality. Read more at http://www.dinosaurtheory.com/hell.html. Galileo
    Response:

    [DB] But then again, one of the biggest problems with science today is that so many people easily reject established science in favor of just about any other alternative that comes along, no matter how tenuous the evidenciary chain that supports it.

  23. Dessler Demolishes Three Crucial 'Skeptic' Myths
    Thanks Chris. I appreciate your tone (and your patience). Both papers (thanks) deal with terminations. I am struggling to understand the other transition, i.e how a small negative insolation is able cause 800+ years of temperature decline (during which the temp delta still exceeds the insolation delta, right?) when C02 levels are still rising. Is there a similar paper that explains this? I'd settle for a simple feedback model that can replicate the features seen in the paleo record, namely:
    • power amplification of a periodic input
    • C02 lagging T throughout the entire cycle
    • bounded output
    Does such a model exist? Thanks
  24. Climate Communication: Making Science Heard and Understood
    A pirate, You can always google climate surveys to see what others have put together. There are numerous reports from various organizations surveying the general public, why reinvent the wheel? I would look at surveys that scientific organizations used (or surveys that went into peer reviewed papers). If you find 5 or 10 surveys you can pick the questions that you like the best. You must decide what the focus of your survey is. Do you want to survey peoples scientific understanding of AGW, or do you want to survey peoples beliefs on human versus natural causes of climate change, or do you want to probe peoples political stance on actions that should be taken? Do you want to identify misunderstandings? You would use different questions depending on your goals. A couple of different approaches have been suggested on this thread. Perhaps if your request was more specific you could get a few more questions on what you are interested in. A quick Google search will save you much time.
  25. One-Sided 'Skepticism'
    This is now getting plain silly Dr. Pielke. I'm referring to his latest post here. The comments policy here says: "No off topic comments. Stick to the subject at hand. If you have something to say about an unrelated topic, use the Search form in the left margin to find the appropriate page." Others' posts were deleted, his off-topic posts were not deleted. Dr. Pielke received preferential treatment by moderators, and we went out of our way to accommodate him. Unfortunately, Dr. Pielke is apparently, unlike many others here, is unwilling to follow some simple rules and speak to the science in question on the relevant thread that deals with that particular scientific topic. I am very sad to say that Dr. Pielke's latest post on his blog (which does not allow comments) also means that I was wrong when I said earlier that: "I trust that Dr. Pielke and Mr. Watts being men of integrity are above misrepresenting or "spinning" what has transpired thus far."
  26. One-Sided 'Skepticism'
    Ditto what CBD said in #147. It's understandable that Dr. Pielke would want to defend those he has worked with and believes are good and honest scientists. However, Dr. Pielke has refused to acknowledge the behavior of his colleagues outside of their collaborations (i.e. misinforming Congress, the American public, engaging in real ad hominems, etc. Apparently only the behavior Dr. Pielke witnesses firsthand counts. And that's a problem, because then not only does he fail to hold his colleagues accountable for their unacceptable behavior, but he criticizes those of us who do try to hold them accountable.
  27. Positive feedback means runaway warming
    True but irrelevant. The candidate system must be capable of power amplification. The output variance (power) in the passive system you describe (unit forward gain, attenuated feedback) can never exceed the input variance. In the system we are considering, the output variance due to Milankovitch forcing exceeds the solar variance from same.
  28. Heat from the Earth’s interior does not control climate
    JohnH#12: I was hoping you were kidding; it's just so easy to put the blame for all the world's ills on the poor cosmic rays. Let's see: LBL's muon page gives an average surface flux of 167 muons per second per sq meter, with an average of 4 GeV each; convert eV per sec to watts; that's a delightfully toasty 10^-7 W/sq meter.
  29. One-Sided 'Skepticism'
    Rob Honeycutt wrote: "Am I reading this correct, that Dr Pielke is only concerned about what he considers derogatory representations (regardless of the content of the actual posts) of specifically colleagues whom he has directly worked or interacted with?" In fairness to Dr. Pielke, I don't think his point in citing his connection with Spencer and Christy is to say 'only scientists I know deserve respect'. Rather, I think his point is that he has direct experience and thus 'knows' that they 'produce good work' or some such. However, he also 'knows' that Anthony Watts is dedicated to the highest scientific standards, so... Essentially, it comes down to Dr. Pielke citing his 'opinion' and then refusing to say anything about the (frankly overwhelming) evidence to the contrary. At which point it really boils down to the old saw about people being entitled to their own opinions, but not their own facts. Believing that Anthony Watts is dedicated to high scientific standards is certainly NOT a reality based 'opinion'. If it were, Dr. Pielke could defend his position against the many cited examples to the contrary rather than just evading them. This is also not 'skepticism', not even "one-sided" skepticism. It is denial.
  30. Dessler Demolishes Three Crucial 'Skeptic' Myths
    jpat (@ 63) If you re-categorize "positive feedback" as "amplification" that might help to better understand "positive feedback" in the context of climate science. We could consider the dominant feedback to any atmospheric warming (whether greenhouse-forced or solar-forced); i.e. the water vapour feedback. Say the primary warming from enhanced [CO2] is 1 oC, and the water vapour feedback results in an additional primary warming of x oC, the total warming is something like 1 + x + x^2 + x^3 + x^4 ... which is 1/(1-x). So if the water vapour response to a 1 oC warming is 0.5 oC then the total warming when everything comes to equilibrium is 1/(1-0.5) = 2 oC. The same argument applies for other feedbacks. In other words there doesn't have to be any "negative feedback"...under the effect of a forcing the system evolves to a new equilibrium. If you're interested in what's actually happening during the transition from glacial to interglacial transition try these papers entitled Ice Age Terminations, and The Last Glacial Termination, respectively.
  31. One-Sided 'Skepticism'
    I wonder what Dr. Pielke would do if presented with a list of several hundred actual ad hominems issued by himself and the many scientists with which he's worked over the years (I could harvest several hundred from WUWT alone, never mind Spencer), as opposed to the few that he accuses SkS of committing (which aren't even ad hominems). Would he then admit his error? I feel that this thread has given Dr. Pielke every opportunity to illustrate that he is not a hypocrite, and yet he has failed to avail himself of those opportunities. So be it.
  32. Heat from the Earth’s interior does not control climate
    @ muoncounter #9: About the size of a pinhead I would imagine. My question about cosmic rays was tongue-in-cheek. PS -- I'm suffering from Pielke-fatigue syndrom so please forgive me.
  33. One-Sided 'Skepticism'
    Stig Mikalsen: Well said! Thank you.
  34. Just Deserts: Winning the 2011 Eureka Prize
    I wanted to belatedly add my congrats. This site is simply astoundingly good - and the amount of work involved must be mind-boggling. Well deserved.
  35. Heat from the Earth’s interior does not control climate
    "The heat added to each cubic metre of water every year would equal the body heat from a mouse swimming in that water for a few minutes! " Hmmm...I don't know about you, but I've noticed a substantial increase in mice rummaging through my garden recently. Next climate myth, coming right up! ;-)
  36. One-Sided 'Skepticism'
    I propose SkSc add another button, "Skepticism a’la Pielke sr". As far as I can tell, he has here been reminded by moderator 7 times (8?) what the thread is about. Despite the post, the update, the moderator reminders and some 70+(?) relevant comments he has just refused to answer simple questions. He has refused to either support or withdraw his unsupported and false accusations and he is still unwilling to be skeptical about his fellow "skeptics". Instead he has kept on diverting attention and defending one "side". Doesn’t this behavior look oh so familiar? Look into his blog and his history and the readers can then judge for themselves. He himself probably thinks he is "constructive" and "balanced", but just take a closer look and it becomes clear that his embarrassing performance in this thread has a simple explanation. Pielke sr. is utterly one-sided, and not much better than the colleagues he prefer to defend. You can even start very simple, with his "I have worked with Anthony and he is devoted to the highest level of scientific robustness", contrasted with his view of SkSc ("If you want to be taken more seriously by others outside of your view on the climate issue, you should be provide more balance"). What a denial. Then look at his "I object to personal attacks by anyone on any side of this issue". And contrast that with what he actually does; defending the misinformants (sorry) "he has worked with", and ... who else? Revkin once in 2005? What a denial. One more idea is that Albatross could "condense the many questions directed at Dr. Pielke into a few pertinent questions so that he is not overwhelmed". Those questions Pielke can post on his own blog, and answer them there. I don’t think Pielke will ever actually answer, but hey Dr. Pielke: I will be able to admit I was wrong.
  37. Are you a genuine skeptic or a climate denier?
    Dana69#468: "it seems you cherry picked" Not. I specifically addressed my comment to your objections to the word 'denier'. "the fact that the majority of scientists no longer debate the subject should not lead one to conclude that the debate is concluded," I'm not sure what you mean by that. Would it be better if there was widespread disagreement among the majority of scientists? " that we have an answer, or that the science is settled." You've agreed with the physics, as you stated above. That is the science; that much is settled. " Much of what we’ve learned suggests that we actually know less than we previously thought we did." Really? Satellite temperature and ice extent measurements started 30 years ago. We do indeed know a heck of a lot more now than we did then. "The projection arc is upwards of 100+ years." So? All usable scientific theories are both prohibitive and predictive: they must specify what will and what will not happen. Climate is inherently a long time scale study; the statement 'here is what the current understanding of the science predicts given these scenarios' is entirely appropriate. You speak of politics: If we, as a society, do not pay attention to the full range of potential outcomes that science can forecast, we are not making an educated decisions. We are in the position illustrated on the cover to John's book. Why shy away from discussing the worst-case scenarios if they are part of the spectrum of possibles? That is why the deniers (oops, I said the bad word) of today are playing with fire (and flood).
  38. Dessler Demolishes Three Crucial 'Skeptic' Myths
    jpat - Reply on the far more appropriate thread here.
  39. Positive feedback means runaway warming
    jpat A gain < 1.0 can still provide a several-fold amplification: Output = Forcing / ( 1 - gain ) A gain of 0.9 will result in an amplification of 10.0, as the sum will be 0.9 + 0.9^2 + 0.9^3 + ..., summing to 10x.
  40. Heat from the Earth’s interior does not control climate
    Good debunking of yet another climate myth! MarkR in #6: You were faster than me with your comment about the 30% of reflected solar energy, the 102 Watts shown to the left in figure 6! Something that should put geothermal heat in the correct climate perspective: A couple of years ago I debated this issue with a denier on a Norwegian science website. My two central arguments were exactly what is mentioned here: The energy flow from the Earth’s interior is several thousand times smaller than that from the sun, and there are no reasons to believe is has changed much for millions of years. He then claimed that undersea volcanoes are a major heat source and that they can explain the recent warming. After some research on the heat capacity of water and the energy output from volcanoes measured from satellites, I came up with an interesting calculation: If 1000 undersea volcanoes, each with the same energy output as Etna in 1992 (12 gigawatts), had continuous eruptions, it would take them about 15,000 years to heat the oceans by 1 K if all that heat stayed in the oceans and wasn’t lost to the atmosphere and space. The heat added to each cubic metre of water every year would equal the body heat from a mouse swimming in that water for a few minutes!
  41. One-Sided 'Skepticism'
    Rob Honeycutt: It would be prudent for SkS to ask Dr. Pielke for a complete list of the other scientists that he has worked with during his career.
  42. Dessler Demolishes Three Crucial 'Skeptic' Myths
    Feeback with a gain < |1.0| is always stable. Think of an operational amplifier with gain < 1.0 - stable. Yes of course but if the open-loop gain <1 the closed loop gain is also <1. We are I thought, only considering a system capable of amplifying the small forcing induced by the Milankovitch cycles.
  43. apiratelooksat50 at 07:14 AM on 18 September 2011
    Climate Communication: Making Science Heard and Understood
    My request was an honest attempt to allow the followers of this site to design a survey that my classes could disseminate and analyze results. Very, very few people offered anything constructive (with the exception of Jonathan, Muon, etc...), instead most of what was posted was kvetching. The idea has evolved, but I seriously would like a survey that I could present in a before/after context to the students, and eventually to the local public (science department, general faculty, etc...). You obviously know my stance and question anything coming from underneath my sphere of influence. I think it would be enlightning to all involved to post a survey from a pro-AGW person and compare the results. It is very difficult to create an unbiased survey. I welcome the opportunity from the truly learned people on SKS to educate myself and my students.
  44. Dessler Demolishes Three Crucial 'Skeptic' Myths
    "Moderator Response: You do know that "positive feedback" does not necessarily mean runaway feedback, right?" Condescension is usually not conducive to dialog. We're running into cross-discipline semantics. Positive feedback is self-enforcing and will operate on any noise present to select and reenforce components near the system eigenvalues. The amplitude at this frequency will grow without bound until a limiting mechanism is encountered. This limiting mechanism is best viewed as a countervailing negative feedback which works to constrain the poles to the jw axis. #57 - I was not trying to postulate a novel negative feedback mechanism. I was referring to whatever you want to call the thing that prevents thermal runaway. So rephrasing my original question, why won't this same mechanism mitigate the effects of AGW, limiting the temperature excursion to that which would of been encountered naturally?
  45. One-Sided 'Skepticism'
    Am I reading this correct, that Dr Pielke is only concerned about what he considers derogatory representations (regardless of the content of the actual posts) of specifically colleagues whom he has directly worked or interacted with? So, Monckton's Myths and Lindzen's Illusions are okay? (Assuming he's not worked with Lindzen.) And therefore, also, all the derogatory representations made toward Trenberth, Mann, Phil Jones, and a long list of others, is also fine and dandy? I'm trying to determine if he is only offended by what he considers derogatory representations of people whom he chooses to agree with or if it's truly limited to those whom he has worked with.
  46. Dessler Demolishes Three Crucial 'Skeptic' Myths
    jpat - Please read the link you were pointed to. Feeback with a gain < |1.0| is always stable. Think of an operational amplifier with gain < 1.0 - stable. There may be oscillation enroute to the stable state, depending on lag elements, but no runaway will be seen with a gain less than 1.0, as each cycle of feedback is lesser and lesser, damping out. As to the Milankovitch cycles - feedback operates on forcing changes both positive and negative. This means that when orbital mechanics decrease insolation, that negative change in forcing is amplified by feedbacks as the earlier positive change was. The forcing acts as a control knob.
  47. Dessler Demolishes Three Crucial 'Skeptic' Myths
    jpat - please see CO2 lags temperature.
  48. Dessler Demolishes Three Crucial 'Skeptic' Myths
    #57 - Ok, we've identified the limiting mechanisms. But unless you are saying the system is self-oscillatory, you still need to explain how the small forcing function can turn the battleship around. The CO2 lags by 800 years or so. After the orbital forcing turns negative, we see falling temps while the CO2 is still rising and the GH effect is near maximum. How is this possible? Is there a paper someone can point me to that provides a mathematical model for this?
  49. One-Sided 'Skepticism'
    Dr. Pielke's parting shot reminds me of the chorus of "Charlie and the MTA" made famous by the Kingston Trio. Did he ever return? No he never returned And his fate is still unlearn'd He may ride forever 'neath the streets of Boston He's the man who never returned.
  50. Dessler Demolishes Three Crucial 'Skeptic' Myths
    CBDunkerson - I am unaware of any system theory which differentiates positive feedback from "run-away feedback". Feedback is either regenerative (left half plane poles) or regenerative (RHP poles). All regenerative system run away unless there exists some limiting mechanism.

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