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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 63101 to 63150:

  1. 2012 SkS Weekly Digest #8
    I'm from the U.S. In no particular order here are my top 5 climate science sites: Climate Progress Open Mind Climate Denial Crock of the Week RealClimate DeSmogBlog I see that Richard Lindzen gave a talk to the British House of Commons. It appears to be the same old stuff. But is there any chance you'll do a debunking post on it?
  2. 2nd law of thermodynamics contradicts greenhouse theory
    DB, actually the PDF specified by YOGI appears to be a different screed by Postma wherein he insists that the "Greenhouse Theory" contradicts the laws of thermodynamics. Including alot of the usual 'energy cannot flow from a colder area to a hotter one' idiocy. So, complete nonsense... but on topic nonsense.
    Response:

    [DB] Noted.  But as Dikran points out, Postma commits a great number of grievous errors in this new piece.  Perhaps a continuing series on Postma, with this one comprising "Joseph Postma is Wrong About _________, Pt. 4"?

  3. Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
    mspelto#42: That's what I was afraid of. As with Arctic ice melt, this is another one of those 'its worse than we think' moments. Would it be possible to do a 'ground truth' calibration, bringing the GRACE-derived ice loss computations into better agreement with what you actually see? (I'm old enough to remember the world before satellites, when you actually had to use measurements made by folks in the field).
  4. The Deep Ocean Warms When Global Surface Temperatures Stall
    RobP#67: "the warming rate abruptly shrinks after 2003, when the more precise ARGO data makes up the majority of ocean temperature measurements." If you are suggesting that the change in rate is due to the changeover in data acquisition systems, wouldn't it be better to say 'the warming rate apparently shrinks'? But even that case in not well-supported by the error bars in your figure b: On the more recent data, uncertainty appears to be ~3x that of the older data. Are we able to show a statistically significant difference between, for example, the central NODC bar of 0.5+/-0.2 (early) and 0.1+/-0.6 (later)? This combination of 'surface temperatures stall' and 'ocean heating slows' seems to be the message we hear from the opposition. A better message could be phrased: Thermal cycles in the oceans are as yet not completely measured; we do know they have the capacity to mask and delay what we see on the surface by storing large quantities of energy. Despite that, as FR2011 show, there's been no change in the underlying atmospheric warming rate. And thus we really should be worried what will happen when that heat comes back to see us, especially since even the la Nina years keep getting warmer.
  5. Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
    Numbers aside, am I the only person here troubled by the choice of map projection used in Figure 1 for the GRACE trend? I thought we had long ago abandoned using projections that showed Greenland as almost the same area as Africa! They were first used to make Europe and the USA seem bigger and more important than they really are. In this instance it makes the "blue" areas of ice loss closer to the poles much larger and more important than they warrant, and the "pink" areas of ice gain closer to the equator smaller and less important. Also, can somebody explain where the ice is that appears to have accumulated in the Amazon basin, Zambia and Singapore? I think the problem for this map is that it is mapping ALL changes in gravity, not just ice loss. I was under the impression that India was still slowly crashing into Asia and pushing up the Himalayas. If that is the case could the growth in mass there be down to accumulated build up of crust material rather than ice in glaciers?
  6. 2nd law of thermodynamics contradicts greenhouse theory
    [DB] I`ll hang my hat on this: http://www.tech-know.eu/uploads/Understanding_the_Atmosphere_Effect.pdf
    Response:

    [DB] You are thus relatively off-topic on this thread.  The more appropriate thread for your discursion is Postma disproved the greenhouse effect.  Everyone please respond there.

    Yogi:  Please read the above thread and the following threads in their entirety

  7. 2012 SkS Weekly Digest #8
    Like Adelady (who is from Adelaide, Australia for the non-Aussies for whom it may not be so obvious) I am from Australia, but from further East and North a bit at Brisbane. My favourite climate science sites (excluding SkS) are: Open Mind for detailed dissection of so-called skeptical arguments; Science of Doom for detailed analysis of the science a very readable undergraduate level; Deltoid for detailed discussion of Australian Media coverage of climate science, and some other gems; Rabbett Run for a quirky look at climate science, climate politics and just about anything that takes his fancy (I did mention quirky, didn't I); and because you've got to laugh if your not going to cry - Throbgoblin, which unfortunately has been inactive for three months but well worth reading back posts if you haven't already. Cutting the list down to five does a great disservice to a number of other excellent blogs, but that is the way the question was framed. I'll cheat a bit and direct you to my largely inactive blog for the full list of blogs I watch.
    Moderator Response: [JH] Asking readers to name their top five sites seemed to be a resonable request. Asking for readers to list more than that would discourage responses.
  8. DenialGate - Highlighting Bob Carter's Selective Science
    Two things stand out from this. First, it should be a relatively straight-forward exercise for skilled scientists to publish peer-reviewed articles which highlight and correct the errors in articles like McLean et al. (2009). I don't want to overburden the excellent work SkS does, but it seems we need a database on those flawed articles that points directly to the published rebuttals (and, in some cases, articles waiting for publication). Second, you mention how Carter has published science in non-science journals. I think it's time for the established organizations in social sciences and other fields, like economics and political science, to step up and start publicly chastising journals for publishing "findings" outside their area of expertise. There's a lot of this out there (think E&E) that gets mentioned in the public policy arena, but they are not peer reviewed by qualified scholars. Economists, political scientists, sociologists, etc. know nothing about about physics, chemistry and biology, so they should stop writing that they do, and be called out when they try.
  9. Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
    muoncounter that is a safe assumption. What looks more reliable detailed mapping of thousands of glaciers indicating large net losses, or a mountain wide assessment that does not fit other observations and is at odds with the Matsuo and Heki (2010) analysis of the same are using GRACE just a year ago.
  10. 2012 SkS Weekly Digest #8
    I'm in the UK First stops of call for discussion of the science and impacts, after here as you say, are Real Climate, Open Mind (Tamino), My View on Climate Change(Bart's) (when he's in the mood to post anything), Science Daily andThe Guradian, though that's as much to see what the media are saying as to get new info. I think I ought to visit The Science of Doom more often. Then places like Planet3.0 for meta-discussions.
  11. David Evans' Understanding of the Climate Goes Cold
    And also, Ms. Nova has been told repeatedly that her beliefs on the science pertaining to this are in error, so Evans knows that too, but insists on perpetuating myths and misinformation.
    She is still making that claim as well - e.g. in comments here.
  12. David Evans' Understanding of the Climate Goes Cold
    Evans has a (new?) somewhat similar article that is being cited by "skeptics". He argues that net feedback is so strongly negative that climate sensitivity is perhaps as low as 0.25 x 1.1 = 0.275 degrees C per CO2 doubling - although he allows that it may be as high as 1 C per doubling. (No citation for that claim though!) And at the bottom the article cites his Electrical Engineering Ph.D. - and argues that EE is "...The area of human endeavor with the most experience and sophistication in dealing with feedbacks and analyzing complex systems...". That's particularly interesting, because the article argues that:
    If a system instead reacts to a perturbation by amplifying it, the system is likely to reach a tipping point and become unstable (like the electronic squeal that erupts when a microphone gets too close to its speakers). The earth's climate is long-lived and stable — it has never gone into runaway greenhouse, unlike Venus — which strongly suggests that the feedbacks dampen temperature perturbations such as that from extra CO2.
    This argument would garner him a Fail in his undergrad automatic control theory classes. He is effectively suggesting to his uninformed audience that there can only be either positive runaway feedback or negative ("dampening") feedback - and that positive non-runaway feedback that merely amplifies a signal does not exist (in practice, perhaps even in theory). His former EE professors might want to have a quiet word with him on that point, as would many amplifier designers. And there's more to dig into in that article...
  13. Monckton Misrepresents Reality (Part 3)
    owl905 - The model therefore shows that greater amounts of heat are being sequestered in the deep ocean when global surface temperatures are in hiatus periods And note the summary at the end: "Heat buried in the deep ocean remains there for hundreds to thousands of years. It is not involved in the heat exchange occurring in shallower layers" But the surface layers are warming. We experience that as global warming. This appears to be a common fallacy - that the deep ocean warming means the surface ocean isn't warming. That's clearly not correct, and perhaps needs a blog post to dispel this canard.
  14. Philippe Chantreau at 20:22 PM on 27 February 2012
    The Deep Ocean Warms When Global Surface Temperatures Stall
    Adelady, that instructor was correct. Most people approach airplanes from their exeperience driving cars but they are much more similar to boats. They move in a fluid. That was a major message I tried to pass on to my flight students. It applies in all conditions, not only bad weather. Another important message was that one should not find himself in bad weather if applying proper decision making...
  15. Monckton Misrepresents Reality (Part 3)
    I think talk of fraud is wrong headed. I think Monkton indulges more in willful blindness than in lying. He knows what he wants to believe and reads to find something that supports it. He belives his own BS because he can't bear to admit that he might have to come to an accomodation with political opponents. Like most deniers! And there can be other things such as conceit as well.
  16. Monckton Misrepresents Reality (Part 3)
    @Tom Curtis, thanks for the effort, but you angled off in the wrong direction. The objection isn't that heat doesn't get to the deep oceans. The objection isn't that an energy-imbalance is masked at the surface by the oscillation ('hiatus' is a mirage). The objection is to the unsupported claim that the heat transfer down deep is interim or temporary (and it is part of this article). Maybe the words from the recommended thread will register: "The model therefore shows that greater amounts of heat are being sequestered in the deep ocean when global surface temperatures are in hiatus periods." For THC cycles, that's 800 to 1,000 years ... and longer if the only draw out is during the millennial cooling towards the next Ice Age. Again, thx for the time and effort in responding.
  17. 2012 SkS Weekly Digest #8
    I am Dutch and my most favorite sites are: climate change: The Next generation Has a very good collection and archive of news Tamino Statistics climate crock of the week Good fun and the videos started my skeptical view to the "skeptic" point of view Jules klimaat blog Unfortunately not active enough but some good refence to the Dutch "sceptics" Barry Bickmore For a different point of view
  18. 2012 SkS Weekly Digest #8
    My country of residence is pretty obvious. Same as Doug for Crock of the Week, Real Climate and Climate Progress. then Arctic Sea Ice or The Chatter Box for ice related stuff and Science Daily: Earth & Climate for the occasional surprising item.
  19. 2012 SkS Weekly Digest #8
    The ones I regularly visit are: deSmogBlog Climate Denial Crock of the Week Real Climate Climate Progress I'm not claiming they are better or worse than any others, but they are at my (non-scientist) level, in general.
  20. The Deep Ocean Warms When Global Surface Temperatures Stall
    From Peru - "What changed during the 2000s?" ARGO came along. With its greater precision we now have the capacity to see what is going on in the individual layers. It would take a very detailed re-analysis of the old data, and removal of errors & bias, to ascertain whether this divergence between the 0-700 meter and 0-2000 meter layer in the 'noughties' is in fact a novel feature.
  21. The Deep Ocean Warms When Global Surface Temperatures Stall
    From Peru - How can a forcing warm the atmosphere and the land, while at the same time producing a much smaller upper ocean warming and then producing significant warming in the deep sea?" That's not correct. The upper ocean, the top 700 meters, has warmed considerably through the noughties, although most likely at a slower rate than the 1990's. A part of the problem is the switch over from the less precise XBT-based system to ARGO. See SkS post: Search For 'Missing Heat' Confirms More Global Warming 'In The Pipeline' and pay particular attention to figure 2: Note how the warming rate abruptly shrinks after 2003, when the more precise ARGO data makes up the majority of ocean temperature measurements. It suggests that a large portion of the apparent slower heating rate isn't actually real, but a consequence of moving from one system to another. So does that mean there was no slowing of the ocean warming rate? I don't believe so. This is apparent in the thermal component (expansion) of sea level rise. The rate of ocean warming still appears to be lower than the 1990's, but the recent paper Jacob (2012) indicates the melting of land-based ice may be smaller than previously thought, and therefore the estimates of thermal expansion may have to be revised upwards. Volcanic aerosols (Solomon (2011), and the downward part of the solar cycle would have also contributed to a slower rate of ocean warming through the noughties, and Asian aerosols (pollution particles) may also have played a part. Still awaiting papers to be published on that. At some point through this ocean warming process we should expect the warming in the subsurface layers to exceed that of the surface layers, because earlier warm periods in Earth's history had surface-to-deep ocean temperature gradients much smaller than today. Of course I'm assuming that such a trend is typical of all warmer periods, it may not be, but so far it seems to be headed in that direction.
  22. Radiative Balance, Feedback, and Runaway Warming
    GC - do any of these theories you mention include predicting the lapse rate (ie these are not variations on Postma's stuff. And also manage to explain the observed DLR somehow does not cause surface temperature to increase? A link to a full, mathematical exposition (preferably published) would be appreciated.
  23. Radiative Balance, Feedback, and Runaway Warming
    Jose_X #36 >Chris #25, I meant Chris #24. Also, thanks for that explanation in #24 since I had seen that equation recently but it had turned me off from reading too much more (of whatever it is I was reading related to feedbacks).
  24. Monckton Misrepresents Reality (Part 3)
    Tom Curtis @2, While I agree with the overall intent of your comment, I believe if there is a clear case of fraud it should be pursued. Bear in mind I do not think there is likely to be enough evidence to convict Monckton. My understanding of the legal requirements is that he would have had to deliberately misled or falsified information with the intention of financial or personal gain. Proving that the deception was deliberate, or that the intent was financial or personal gain, would be hard without some smoking gun. Bear in mind, this is also quite distinct from instances where people are simply (and demonstrably) wrong, even if they argue loudly and repeatedly for those wrong positions.
  25. Radiative Balance, Feedback, and Runaway Warming
    Chris #34, >> But I wouldn't put much meaning into the "average sensitivity" of the planet. .. a lot of people run into mistakes of trying to figure out the sensitivity of a doubling of CO2, from say, how much CO2 contributes to the 33 K greenhouse effect. Exactly. I think this is something that at least some people might not realize. Since I have seen RW's comments on various forums, I not only think this is/was a main issue s/he did not see, but many of the people replying to RW apparently didn't clearly understand this was the problem. The responses did almost inevitably include someone early on pointing out the non-linearity issue, but possibly RW did not realize what that meant and then the conversation moved on to different argumentation. A graph can help people understand that point. Mind you, I haven't seen too many people get hung up on that (certainly not like RW), but the doubt might be lingering without them being able to put it into words. Look at the reaction of sauerj#16 to a related issue.. cleared up by this very nice presentation. Additionally, showing a nonlinear curve that shows H2O effect kicking in gives insight that it's not really CO2 that does the damage. Seeing a graph with the increased (or decreased) slope and a bit of a "knee bend" (when seen from afar.. to see the forest from the trees) helps add urgency and legitimacy to the fears of many climate scientists. >> climate sensitivity is frequently taken as being inversely related to the slope of TOA flux vs. surface temperatures Thanks for the heads up. It still might be interesting to consider the flipped graph since a higher slope is probably more closely associated in the mind with a threat in most uses. A logarithm, for example, is more likely to be seen as "safe" than an exponential curve[*]. This is perhaps another case where those new to the field are likely to misinterpret. Most people's experience (of those who remember) is that we vary the x coordinate to see the effect in the y coordinate. y=f(x). More people might better understand, if you are varying a forcing[**] to then examine the effect on temperature, that you are varying the x coordinate to measure a change in the y. This view is more intuitive probably to most thinking cause-effect relationship. [*] Note, that the main topic being tossed around by laypeople is this "climate sensitivity" value, so it might help to see that relationship directly on a graph as we might be likely to interpret that graph ("cause-effect" <-> "x-y"). [**] "Forcing" is another term that I recently saw clarified that might confuse some people when hearing "CO2 forcing". As concerns the feedback confusion, engineers would likely model CO2 within the system equations. Someone recently wrote somewhere that it's equivalent to knobs being turned in a sound processing unit.. You don't model that as adding a signal strength but rather by varying parameters of the system. Eg, you wouldn't add a force vector but you'd change a viscosity coefficient. Writing an article to explain why 2xCO2 is modeled as a forcing (for sensitivity analysis) could help. >> I think one of the most definitive sources is Roe, 2009. Thanks, I had just downloaded that this week (from a judithcurry link I saved, where she too recommended it). A shorter more accessible description (and on this site) than a 25-page pdf that a friend might point towards might increase the number of people who read that. [I'll go and read it soon I suppose.] >> ice on Earth is only a very small contribution to the planetary albedo I did not realize that. Maybe here too is a lesson of sorts since I probably developed that intuition from comments made by others and from the idea that rays bouncing off the earth makes sense off a white surface. I know that the incident angle plays a much greater role, but I still got the impression ice was significant (although it is at the poles mainly, meaning there is less contribution to average albedo as the incident angle effect already probably dominates).
  26. 2nd law of thermodynamics contradicts greenhouse theory
    YOGI writes: "How come if 239W/m go in and 239W/m go out, that 396W/m exists within the system ? surely that violates the conservation of energy law ?" Really? So, on your world, if the stream feeding into a lake carries 239 m^3/s and the stream flowing out of the lake also carries 239 m^3/s then the lake cannot possibly hold 396 m^3 of water? How very sad for you and your world where clouds do not precipitate out of the atmosphere when the temperature decreases. Here on our Earth planet things work differently.
  27. The Latest Denialist Plea for Climate Change Inaction
    Speaking of the Angliss-Rutan conversation, reading the full set of comments on the original thread is even more eye-opening. Commenters other than Angliss provide Rutan with a great deal of supplementary information demonstrating that many of his claims are indefensible - and in his responses to them in comments (which are not found in the summary post linked at #52) he ducks, weaves and gallops with the best of them. And speaking of psychological projection - Rutan's schtick is big on AGW communicators engaging in "data presentation fraud" which he argues inappropriately scares the punters - but his own anti-AGW slide deck is so full of it, it's difficult to find one single slide discussing science that presents a fair view of the data.
  28. Radiative Balance, Feedback, and Runaway Warming
    Chris #25, I agree Charlie is correct, but I think you are misunderstanding something. It's not the amplitude of that expression you mentioned that defined pos/neg in the traditional feedback sense since the sign is not changing in that expression (only the magnitude). Net negative feedback from Stefan-B (as Charlie mentioned) means that as we increase temperature we get a counter effect to that raise (a dampening effect.. a "force" that would otherwise make T decrease if it could exist by itself). If we had net positive feedback (in the traditional/engineering sense), on the other hand, we'd get a runaway effect such as one sees when a microphone is brought too close to the speakers.. the signal amplitude blows up very fast (until saturation is hit or some circuit is tripped and shuts it off). Of course, the earth never gets rid of the S-B radiation loss into space, so any "positive feedback" claims would be impossible except within the context of a limited model range (eg, the mic/speaker goes through runaway but only until saturation where the model goes beyond its capabilities... obviously, the mic/speaker runaway doesn't turn into a black hole and suck all the energy from the universe). As stated in Jose_X #30, I do think clarifying well how climate positive feedback is not the same thing at all as traditional (engineering) positive feedback would really get a lot more engineers to pay attention and say "oh, that's what they mean". The climate scientists appear to be in an imaginary world to some engineers first looking at this question of pos vs neg climate feedback. Just like you think Hansen is off, many engineers think all of climate science must likely be off in thinking we are *currently* in a runaway situation that will inevitably consume the entire planet. Perhaps those climate scientists don't even know mathematics. Someone has been conning them to use some computer program and they blissfully live in their own made-up world. [In reality, many engineers probably suspect they are misunderstanding something, but the net result is similar if instead of learning and becoming advocates they lose interest and perhaps afterward sign on to some Internet list of skeptics.] Feedback analysis obviously has limitations. I would not criticize the definitions used in climate science since those appear to be useful definitions for the context, but, I think this change in definitions should be made more clear to an audience composed of technically savvy people. I would consider adding in an "argument" on the website that addresses this feedback issue, even if the audience would be limited. The educated engineer/scientist(?) is an influential audience and can be quiet a thorn or otherwise a useful ally.
  29. 2nd law of thermodynamics contradicts greenhouse theory
    YOGI... Look, people are not trying to pile on, even though it may seem like it. What is frustrating is that you're clearly confusing your lack of knowledge on this subject with there being something wrong with greenhouse theory. It's a very complex subject. But rather than assuming that 150 years of research has somehow produced an error that has somehow slipped past 10's if not 100's of thousands of scientists, how about just acknowledging that maybe you need to be better trained to even begin to understand this subject. It's great that you are trying to propose questions but the ones you're asking are really pretty easily answered if you take some time to better understand the subject matter.
  30. Climate change models underestimate future temperature variability; food security at risk
    Apropos these comments about England (expect to be there in 2 weeks), I think you can add this fellow to climate skeptics who make predictions: Doug Proctor Did a drive-by over on real climate.
  31. Radiative Balance, Feedback, and Runaway Warming
    gallopingcamel, These exchanges really take away from interesting science, and your claims have absolutely no merit. I'd ask that you read an intro radiation textbook (see Grant Petty for a good undergrad level text that is still quantitative and sophisticated enough for solid understanding).
  32. Radiative Balance, Feedback, and Runaway Warming
    Jose X, thanks for your comments. Your understanding is rather good for being new, but just to reply to a few issues: 1) It's certainly true that climate sensitivity is a function of the equilibrium climate, and to what extent it can be linearized for small changes is still up for some debate. This is one of the issues with using paleoclimate data from the Last Glacial Maximum and applying it to the future. But I wouldn't put much meaning into the "average sensitivity" of the planet. Radiative transfer is a rather non-linear subject, and a lot of people run into mistakes of trying to figure out the sensitivity of a doubling of CO2, from say, how much CO2 contributes to the 33 K greenhouse effect. By the way, I guess I should have specified, but the outgoing radiation in these plots is all from TOA, not surface. Also, climate sensitivity is frequently taken as being inversely related to the slope of TOA flux vs. surface temperatures (e.g., see this graphic) 2) Your point about varying definitions of 'feedback' are well taken. Lindzen does describe the theory of some of this well in several of his papers, but I think one of the most definitive sources is Roe, 2009. 3) Your point 3 is off-target because ice on Earth is only a very small contribution to the planetary albedo (which is dominated by clouds, whose distribution is governed largely by the large-scale dynamics). Ice albedo is important as a local feedback, and there would be a lot of climate consequences to melting the ice (sea level, altering the atmospheric circulation, etc) but it wouldn't have the type of impact on albedo that you're talking about.
  33. actually thoughtful at 16:22 PM on 27 February 2012
    The Deep Ocean Warms When Global Surface Temperatures Stall
    Actually, from a solar plumbers perspective, convection is harder to swallow than conduction or turbulence. I make my living on water stratification - hot water is more buoyant than cold, thus water heater can deliver almost the entire contents of the tank (cylinder) as the cold water is added at the bottom. We use variations of this trick endlessly to maximize the output of solar thermal systems. However, my earliest design required multiple storage tanks, but only one tank that was exchanging heat with the loads. So I circulated the water, thus moving the heat energy (I think of it as a conveyor belt). And that is the model that I think is more helpful to understand how the heat "bypasses" the upper ocean. It doesn't really, it is an artifact of an incomplete measurement system (ie not enough sensors) and the fact that the heat energy is only sinking in certain areas (and lots of heat is going down in those areas). Conduction and convection (ie a warmer liquid rising and a colder liquid falling due to density), in the absence of turbulent system, don't move heat down in water. But ocean currents that are sinking can carry hot water down with them - and that is the mechanism that explains both how heat gets to the lower ocean at all, and why it isn't uniform (and thus appears to bypass the upper ocean). I should point out I don't have any papers to back up this view - just my livelihood.
  34. Radiative Balance, Feedback, and Runaway Warming
    gallopingcamel - I have two issues with your last post: (1) No links. No references. (2) No assertions or evidence from those authors to be considered. What is it that you are asking?
  35. Radiative Balance, Feedback, and Runaway Warming
    > It's not clear to many that H2O is a dominant effect that has only kicked in aggressively for temperatures in the vicinity of where we are (eg, say within the last 10 K, I'd guess) First of all, I am not clear on this since I have not thought about it for too long and haven't come across the statement above. Second, would I be guessing well by saying that, instead of "10K" (a mistake), 20-30K lower in global average temp would result in non-dominating ghg effect contributions from H2O and the correspondingly lower climate sensitivity, as judging by this graph http://upload.wikimedia.org/wikipedia/commons/4/41/Relative_Humidity.png and considering that H2O is about 70% of the ghg effect today with CO2 making up the majority of the rest?
  36. Radiative Balance, Feedback, and Runaway Warming
    Chris, [snipped] Your participation in discussions relating to radiative processes at the "Science of Doom" was stimulating even though we seldom agreed. Here is a question for you. I am a physicist. Other physicists such as Nikolov and Zeller and Robert G. Brown can explain planetary surface temperatures based on TSI, Stephan-Boltzman, albedos and the gas laws. So why do you think that Radiative Transfer Equations (RTEs) have any significant influence?
  37. Radiative Balance, Feedback, and Runaway Warming
    Point 1: I agree with sauerj#16 that more can be done to extend this article, eg, by looking at how H2O affects climate sensitivity all else remaining equal. It's not clear to many that H2O is a dominant effect that has only kicked in aggressively for temperatures in the vicinity of where we are (eg, say within the last 10 K, I'd guess). Of the 33 ghg warming, a major contributions is only "now" being added, because of H2O. In other words, the *average* sensitivity of the planet (eg, starting from no sun or from 1.0 albedo) is much lower than the current sensitivity. We note this by looking at instantaneous tangent line slope (derivative) vs the secant that represents the average slope between our current point and the origin. I started writing up something very similar (but instead TOA flux vs surface flux), as I think showing that graph would help commentator "RW" clear remaining doubts. Ie, it would explain what sensitivity is and how it grows much faster as H2O vapor grows appreciably for a given level of CO2; all other ghg gases remaining constant, add heat from the sun has a much more powerful effect once H2O kicks in past the level needed to match the other ghg effects (earth generally has existed in that range thanks to its distance from the sun, etc). Also, I would place temp on the y axis in order to make it easier for those with modest mathematical bent to follow. You want agreement with the climate sensitivity definition if possible. Greater climate sensitivity should be seen as greater slope on the curve (in the traditional mathematical sense of y_delta/x_delta) and not a smaller/flatter slope. The sensitivity question is a very important one and should be highlighted well.. Point 2: However, I would consider an article view (or related article) to appeal to engineers [can skepticalscience add an "engineer view" for select articles.. beyond the easy, intermediate, advanced views?]. I would clarify that "positive feedback", as it is used in system's analysis and various engineering disciplines, has a different definition than climate positive feedback. This article covered the essence of this point (runaway vs not runaway), of course, but more can be said explicitly to place it in the context of traditional "positive feedback". I have noted that many engineers are skeptic, and I can relate to this particular misunderstanding. So, what describes the earth system is "negative feedback" (in the engineering sense) with a small amplitude component that likely is positive but some skeptic scientists claim could be negative due to clouds. Climate scientists don't expect that positive component to be larger in magnitude than the base negative feedback (at least not any time soon and/or within the confines of existing parameters). The key point is that any net (engineering) "positive feedback" leads to runaway behavior, by the definition used by many engineers, and we want to clarify this issue. It should be clarified that climate scientists call positive feedback simply a less negative feedback. Also, the climate models aren't feedback models, so this distinction is not important for generating future projections. In other words, the scientists' "mislabeling" is inconsequential to the calculations they perform. The "negative feedback" (engineering definition) of climate models is implicit (as mentioned in this article) from the obvious cooling effect of the 0 Kelvin outer space boundary condition and how that is incorporated into the calculations. I will look more carefully at Lindzen's "tropics" feedback analysis (maybe others have already) to see if this issue crops up. It probably isn't an issue, but I am curious. Point 3: I suspect that the albedo might change significantly if ice cover starts to disappear in very large amounts. I might not be thinking clearly, but a change in albedo of say 20% (eg, .06) would be more than merely Apocalyptic when we consider how little the earth's effective emissivity to shortwave changes with a few degrees C change at the surface (right?). Isn't most natural variability equivalent to say +/- .5 C, and isn't this change associated with a tiny percentage change in solar irradiance? Now imagine an increase of 20% incident solar flux rather than a fraction of 1%. [Am I missing something?] [BTW, I am fairly new to this and have lots to learn so I might have misjudged various issues here.]
  38. Scafetta's Widget Problems
    andylee - "I would tackle it from a signal processing and noise reduction point of view - start by subtracting the effect of everything we know from the climate record - volcanic eruptions, ENSO, CO2 signatures etc, and see what is left over." And that's exactly what Foster and Rahmstorf 2011 did for the last 30 years, and what Lean and Rind 2008 did for the last 120 years. Turns out that there really isn't anything left after you account for solar, volcanic, ENSO, and anthropogenic forcings. No mysterious unknown cycles (MUC's), no 'recovery from the LIA', no cosmic ray influence, or distant supernovae, or orbital resonance from Jupiter/Saturn - it's actually just what we expect from the physics. Oh, and our own actions...
  39. Scafetta's Widget Problems
    I then read the paper... He's obviously spent a lot of time and intellectual energy on this, so I don't dismiss it out of hand. (I take issue with the use of the word "astronomical" - apart from our sun, the nearest star is 4.25 ly away.) He has a point and I don't doubt that planetary influences add some multidecadal red noise to climatic data, but his objective appears to start already from a denialist perspective by distancing himself from AGW advocates: "To understand the reasoning a good start is the IPCC’s figures 9.5a and 9.5b which are particularly popular among the anthropogenic global warming (AGW) advocates" The sun isn't stationary, it is wobbling around a barycentre following a complicated path with approximately a 0.01AU deviation. Consequently the Earth's orbit is not perfectly elliptical and its distance from the Sun also has an n-order Lissajous component. Instead of looking for cycles to fit and then attempting to match them to the climate record to try to mask recent warming, I would tackle it from a signal processing and noise reduction point of view - start by subtracting the effect of everything we know from the climate record - volcanic eruptions, ENSO, CO2 signatures etc, and see what is left over. Then, calculate the waveform of the *distance* of the Earth from the Sun modulated by the sunspot cycle to calculate the irradiance. This is the only method that the planets can affect our climate, short of a collision or extended eclipse. At this point a Fourier transform of both climatic history and derived planetary-influenced irradiance should reveal some common frequencies. Applying the irradiance function to the climate record should automatically damp the signal in the right places, subject to some phase shifting to identify possible latencies in climate response. Anything left over is attributable to something else. Lastly, my favourite sentence: How easy it would be to quantify the anthropogenic effect on climate if we could simply observe the climate on another planet identical to the Earth in everything but humans! But we do not have this luxury. ... ... yet! :-)
  40. The Deep Ocean Warms When Global Surface Temperatures Stall
    What changed during the 2000s? Little to nothing. It's barely ten years. You need at least another 7-10 years of the same before you could even _begin_ to detect anything different going on.
  41. The Deep Ocean Warms When Global Surface Temperatures Stall
    One more question: The upper ocean warmed during the 1970s-1990s period together with the land+atmosphere. Then in the 2000s the strange pattern of warming deep oceans despite non-warming upper ocean began. At the same time, the atmosphere and the land surface continued to warm steadily. What changed during the 2000s?
  42. The Deep Ocean Warms When Global Surface Temperatures Stall
    Sorry camburn, there are probably lots. But what came to my mind was something I read about flying. It referred to old-fashioned clunky type smaller planes of, from memory, 50s vintage. The instructor's words were that it was easier to control a plane in bad weather if you 'saw' yourself as swimming, diving or surfacing in currents, tides or waves.
  43. The Deep Ocean Warms When Global Surface Temperatures Stall
    59, Peru,
    How can the heat had bypassed the upper ocean in the trip from the atmosphere to the deep ocean?
    One of your problems comes from the way you phrased this question. You make it sound like the system is a simple path for heat from atmosphere to upper ocean to deeper ocean. It's obviously far more complex than that.
  44. Global Extinction: Gradual Doom as Bad as Abrupt
    JP40 @ 40, Yes the Foundation series has occurred to me as well, in this context. Perhaps we need to sequester as much of human knowledge as possible electronically, on another body in the solar system, ready to be discovered by some putative future generation after the Fall and Rise.
    It will be our technology that will liberate us from having to live in balance with natural ecology, and will save natural ecology in the far future.
    We place enormous trust in future technology. I hope it will save the day, but I am not so convinced that I could say with certainty that it will do so. I think you have misunderstood part of my last post, which was probably not very clear. My point is that greed drives the development of technology, not the other way around. Unless there is "something in it for me", I am unlikely to come up with a new tool or method. Our whole way of life revolves around satisfying our needs and that translates into greed when we seek to acquire more than we actually need as individuals. There is no basic 'need' to be a billionaire, but plenty of us aspire to it.
  45. The Deep Ocean Warms When Global Surface Temperatures Stall
    adelady@60: Do you have any papers showing this? That the "water language" is similiar to atmospheric functions? The sheer difference in density of mass difference would indicate a HUGE energy differential required.
  46. DenialGate - Infographic Illustrating the Heartland Denial Funding Machine
    Here is an interesting article investigating the funding and tax-deductable status of Australia's Institute of Public Affairs (IPA), which has links to Heartland. Looks like a similar setup - how strange.
  47. Global Extinction: Gradual Doom as Bad as Abrupt
    Sorry for the misunderstanding. It seemed that you were saying that humanity deserves to be punished for its "crimes," and that it would be better if we stayed Australopithecus Aferensis. I do agree with you that our civilization will collapse in the next few centuries, causing a lot of collateral damage, but I don't actually think that it is very likely that there will be a repeat of the P-T extinction. Here are the numbers: by the end of the main phase of the extinction, co2 levels reached 3000 ppm. The IPCC's worst case scenario for co2 by 2100 is 1000 ppm, which isn't enough to cause the gassification of methane hydrate en masse. I think that by 2100 there will be enough anarchy to stop most co2 production, so this projection is optimistic (or pessimistic, however you look at it).  I am confidant that civilization will rise again. However, most of our knowledge will be destroyed, and the recovery will be much slower than if a small portion of it survived somewhere other than earth. Our current situation reminds me of Isaac Asimov's Foundation series. In these books, a mathematician who has found a way to predict the future sees that the galactic empire will collapse, and builds a society on a planet on the edge of the empire, in order to compile and preserve all of the empire's knowledge, and to work to reunite it.  After the rise, we need to make sure that we don't ever rely on something that will have serious long term consequences. The earth may not be able to sustainably sustain very many people, compared to the number we have now, but that doesn't mean those extra people have to not exist, because we don't "only have one planet." There is the possibility of terraforming Mars and possibly Venus, which would give us 2 extra planets to live, outside domes, metal cans, underground complexes, and space suits.  You seem to be saying now that technology is the main cause of human greed, and only depletes resources. This view ignores both the cutthroat imperial politics before the industrial revolution, and technologies like wind and solar energy, that don't deplete any resources. Without our current fossil fuel-fuled economy, we wouldn't be enlightened enough to contemplate its demise. In fact, before the industrial revolution, most people were totally ignorant peasants who only knew what they heard by word of mouth. It will be our technology that will liberate us from having to live in balance with natural ecology, and will save natural ecology in the far future.
  48. Scafetta's Widget Problems
    It sounds preposterous that planets can affect our climate in any astrological sense, and I think we can safely discount any radiative forcing from them, but it is well known that Jupiter and Saturn are largely responsible for the Milankovich effect modifying our orbit's eccentricity, although this happens over hundreds of millennia. I looked for some details of orbital mechanics and found these, (the resonances are fascinating):    http://mrob.com/pub/planets.html    http://en.wikipedia.org/wiki/Milankovitch_cycles As the Sun and Jupiter are the most massive bodies, their barycentre causes the Sun to wobble with an amplitude of 1.5m km over 12 years (0.01 AU). My thoughts on a cig packet: As this period is 12x longer than our year, Earth wouldn't 'see' all of that differential as a significant (1%) change in intensity, but I guess there may be some tiny decadal signal (1/12%) though I'm sure it would average out and be insignificant. Far far less than the effect of the Milankovich Cycle.
  49. The Deep Ocean Warms When Global Surface Temperatures Stall
    "How can the heat had bypassed the upper ocean in the trip from the atmosphere to the deep ocean?" It's only a concern if the mechanism for heat transfer was entirely conduction or general turbulence. We can knock out general turbulence immediately, the oceans do not behave like an earth sized washing machine. Conduction? Obviously an issue at various depths and places, but we already know that there are layers and specific places where the water temperature is very different from nearby waters. What's left? Convection. As soon as you allow for water at various depths to exhibit the same kinds of behaviour as air at various altitudes, it all makes sense. Winds, storms, hurricanes, tornadoes exhibit extreme versions of focused or funnelled transport of air at temperature differentials. Local features like hills, mountains, seasides promote consistent winds, or lack of them in some valleys, and temperature profiles. Translate these various features into 'water language' and it's not so hard.
  50. 2nd law of thermodynamics contradicts greenhouse theory
    Stephen Baines "What is the point of bringing up clouds?" Its the only fair equivalent to a blanket. Full cloud cover at night is the surest way to keep the heat in. But as the Earth is externally heated, it will cool with total cloud cover, as the albedo will be huge. GHG`s have huge holes so are not exactly a blanket.
    Response:

    [DB] Way back here, you were asked to succinctly put forth the one objection that you wanted to hang your hat on.  You have made 6 comments on this thread since then and in exactly...none of them have you done so. Failure to do that amounts to a de facto admission that you are here to simply waste the time of others.

    Cease making unsupported assertions (i.e., lacking support in the peer-reviewed literature published in reputable journals) until you can demonstrate that you are able to carry on a science-based discussion in this forum.

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