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Comments 71101 to 71150:

  1. It's waste heat
    Donthc, others have commented on some of the fundamental errors in your analysis, but there was a particularly odd one which hasn't been remarked on yet; "The heating effect of the sun is a constant..." Right. Constant. Other than... variable levels of clouds blocking it, different surface albedo conditions reflecting it, changes in the intensity of the greenhouse effect, that whole 'day and night' thing, progression of the seasons, orbital variations (c.f. 'Milankovitch cycles'), the ~11 year solar cycle, other variations in solar output such as the Maunder minimum, the fact that the Sun is now about 30% 'hotter' than it was in the Earth's early history, et cetera. You could accurately say, 'the average annual heating effect of the Sun is currently showing only small variations on a multi-decadal scale'... but no, it is nothing like 'constant'.
  2. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    Mikeh--I will check that. Macoles--Excellent point. Heijdensejan--will check. Barry--will check. Thanks to all. Please keep the comments and suggestions coming.
  3. 10 Indicators of a Human Fingerprint on Climate Change
    NBotB, for info on 'ice ages' I'd suggest reading the article on Milankovitch cycles. As the other responses indicate, our understanding of the glaciation cycle is just one of many independent lines of evidence which confirm that fossil fuel CO2 emissions are the primary cause of recent warming. The list of 'skeptic' arguments and the 'search' box at the upper left of the page are good places to find answers to various questions.
  4. Visual depictions of CO2 levels and CO2 emissions
    Lots of crowing that the theory of AGW has again been put to death due to patently poor reporting. Plenty of allusions that John was 'fired' from the site he posts on for revealing such earth shattering information.
  5. Climate's changed before
    lancelot @261, our understanding of what will happen in the near future does not just depend on projections from known physics. We also have the record from the past. The advantage of the record from the past is that we do not need to know all the factors involved to read that record. We do not need to know what the cloud feedback is, for example, for that feedback has been integrated into the results by the best model available to us, ie, the real world. Given that, it is worthwhile examining two particular events, the Paleocene-Eocene Thermal Maximum (PETM), and the Last Glacial Maximum. The PETM was a warming event at the boundary between the Paleocene and the Eocene. Boundaries between geological eras are marked by significant changes in fossil assemblages, ie, by extinction events followed by repopulation with new species. In this case the extinction event was probably brought on by the release of a large amount of methane, which was oxidized to form CO2 and H2O, with the CO2 showing up clearly in the geological record. The effects are summarized in the abstract of one review article as follows:
    "During the Paleocene-Eocene Thermal Maximum (PETM), 56 Mya, thousands of petagrams of carbon were released into the ocean-atmosphere system with attendant changes in the carbon cycle, climate, ocean chemistry, and marine and continental ecosystems. The period of carbon release is thought to have lasted <20 ka, the duration of the whole event was 200 ka, and the global temperature increase was 5–8°C. Terrestrial and marine organisms experienced large shifts in geographic ranges, rapid evolution, and changes in trophic ecology, but few groups suffered major extinctions with the exception of benthic foraminifera. The PETM provides valuable insights into the carbon cycle, climate system, and biotic responses to environmental change that are relevant to long-term future global changes."
    The interesting thing here is that best estimates show that the climate response to a doubling of CO2 evidenced by the PETM is 3.6 degrees C per doubling. That is a climate sensitivity of 0.973 degrees C per Watt/m^2 of forcing. In contrast to the PETM when temperatures where substantially hotter than today, at the LGM they where substantially colder. Again the climate sensitivity can be calculated from known forcings at the LGM and the known temperature difference. Most estimates in doing so come close to that by Hansen and Sato, with a value of 0.75 +/-0.25 degrees C per Watt/m^2. That represents an estimate of 2.775 (1.85-3.7) degrees C per doubling of CO2 (compared to the IPCC estimate of 2.8). Again, I emphasize, no assumptions about feedback values from water vapour, clouds or anything else go into these calculations. The Earth just does what it does, and the comparison between known forcing and known temperature response yields the climate sensitivity. But despite the significantly different continental arrangements, and the very different temperatures, the climate sensitivity estimates from these two periods are in the same ball park, and indeed, in the same zone as the IPCC estimates. When it comes to the basic feedbacks, it is certainly possible that scientists have missed something. Evidence is strong, for example, that they have been underestimating ice and snow albedo feedbacks (positive). They may well also be overestimating the cloud feedback (possibly positive or negative). For that to create a significant problem for their predictions, these errors need to mostly line up in the same direction. What is troubling about the assumption that these errors will fortuitously come out in our favour is that it is also an assumption that the Earth's climate sensitivity is, fortuitously, approximately half or less of what it is when the Earth is hotter (PETM) or colder (LGM) than it currently is. That somehow, and with no physical basis for assuming so, we just happen to be in a goldilocks zone of low climate sensitivity even though hotter and colder conditions are known to have high climate sensitivities. What makes the heroism of this assumption even greater is that it is known that throughout the entire existence of vertebrates on Earth, from the late pre-Cambrian to the present, climate sensitivity has never been far from 2.8 degrees per doubling of CO2. Over 540 million years of high climate sensitivity, but it just happens when we start emitting CO2 at industrial scales, we happen to be in a goldilocks zone of low climate sensitivity? That, at least, is what the so-called climate "skeptics" would have you believe.
  6. Climate's changed before
    261 - lancelot "So if it turns out in a few years that something has been 'totally overlooked', climatologists will be about as popular as bankers!!" It's worth noting - taking the long view - that CO2 as the key to global warming was, in the '70-'80s, the "other factor". You might also want to ask; if it had been overlooked and, indeed, the anthropogenic origins of the observed warming had been overlooked... just how popular would the climatologists been? If you're going to do counterfactuals; Imagen a future generation suffering from land-loss, a crippled bio-sphere, extreme weather etc. Just how popular will our generation be if we had overlooked the anthropogenic side of the equation and possible mitigation policies and if we don't act on them?
  7. Climate's changed before
    May I just say that I really appreciate the well-considered (and well-mannered) comments to my questions on this site. Sphaerica: When I wrote before I was 'half serious' I was referring to my somewhat flippant suggestion of breeding microbes to seed clouds. That idea, even if feasible, wouldn't go very far of course. I do have a purely scientific interest as you say, but there are larger interests too. (-Snip-). Report of an Ad Hoc Study Group on Carbon Dioxide and Climate, Woods Hole, Massachusetts July 23.–27, 1979 to the Climate Research Board , Assembly of Mathematical and Physical Sciences, National Research Council: “We conclude that the predictions of CO2-induced climate changes made with the various models examined are basically consistent and mutually supporting. ... Of course, we can never be sure that some badly estimated or totally overlooked effect may not vitiate our conclusions. We can only say that we have not been able to find such effects.” (-Snip-) CO2 is a GHG. 100% certain. Natural forcings exist. 100% certain. All possible natural forcings or long term effects on climate have been identified and accurately quantified. __% certain. (Fill in the gap?) muoncounter: Dimming is an urban island phenomenon, ok. Not sure how that relates to the question of net irradiance at surface level globally. From Bob Loblaw's posts I suspect the situation is: we use satellites because they are there. But gee whizz, if we could use actual surface monitoring, we would be so much more certain that our estimates are correct. GCOS looks really interesting. Re sphaerica's comment that oceans cover 70% of surface, I don't see why BSRN type monitoring couldn't be done from ship decks. Use some of that £18bn perhaps?
    Response:

    [DB] Ideology snipped.  Stick to the science, please.

    Your Woods Hole report is badly dated.  Various scientific organizations, including the National Academies last year, have greatly linked the certainty of climate change/global warming (as fact) to its human attribution (greater than 90% likelihood).

  8. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    I think this is a worthwhile project. It will only enhance the site to have someone familiar with all the skeptic papers and able to provide an overview. If nothing emerges to challenge the scientific consensus, visitors to the site can be assured we have done our homework.
  9. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    The irony is that Anthony Watts is a co-author of the Fall et al paper mentioned above. "Analysis of the impacts of station exposure on the U.S. Historical Climatology Network temperatures and temperature trends" http://pielkeclimatesci.files.wordpress.com/2011/07/r-367.pdf So one of the great deniers has 0 publications throwing doubt on global warming, but one paper debunking the very issue on which he made his name! :)) Delicious!
  10. Philippe Chantreau at 18:27 PM on 3 November 2011
    It's waste heat
    Donthc, the papers cited in this thread quantify waste heat and find it 100 times too small. If you want to argue that this quantity is in error you have to provide some evidence, not just an opinion. What calculations are you relying on? Nitrogen a GH gas? That's a good one. What else do you have in store? This makes no sense whatsoever: "If CO2 is responsible for warming, why does nuclear plants, which does not produce CO2, still emits waste heat that serves to heat up the surrounding air?" How could the radiative warming from GH gases prevent the waste heat from cooling towers to be dissipated? Why would these 2 processes be mutually exclusive? There is absolutely no reason, unless you have some new funky laws of physics up your sleeve.
  11. Philippe Chantreau at 18:01 PM on 3 November 2011
    CO2 – Some facts, figures and outcomes
    It is unfortunate that SkS has to entertain even the most egregious nonsense for the sake of "balance" or to avoid accusations of censorship and what not. As a result, even the most severe cases of D-K must be tolerated. Perhaps some of the most extreme in this stuff should be dropped altogeher. I mean, really, there are things that are not matters of opinion, and questions to which there is one right answer. Sheesh...
  12. Pielke Sr. and SkS Dialogue Final Summary
    Bob Loblaw - it was this bit: "but heat gets into the oceans by I guess". It is a very common misconception. Perhaps I've misinterpreted his comment, but the "guess" word set off my "spidey sense".
  13. It's waste heat
    Donthc@96 To engage constructively here one is required to provide evidence for one's claims. Amongst many other things in your "thesis" that are without foundation the most obvious is: Nitrogen is not a greenhouse gas...try wikipedia for "greenhouse gas". (this site has a lot of work to do... it's like sweeping grains of supposition off a beach of ignorance)
  14. 10 Indicators of a Human Fingerprint on Climate Change
    #68 and #69, can I add ... Three: we observe the increase in downward longwave radiation and decrease in outgoing longwave radiation at CO2-specific wavelengths. Not only is CO2 the only explanation for warming, we actually see it happening directly. That's the "less heat escaping to space" in the graphic above.
  15. It's waste heat
    Fuel + Oxygen --> Heat + Water + carbon dioxide. more combustion will bring about more production of heat and CO2. Decrease the rate of combustion, and you will decrease the amount of heat released, and reduce the rate of warming of air. The heating effect of the sun is a constant, and will always be there no matter what you do, whereas the burning of fuel is a variable. It is clearly heat which warms up the surrounding air, not CO2. Does reducing CO2 concentration decreases the amount of energy generated from bond breaking of the fuel? An analogy will be that of taking the elevator. When a single person takes a ride in the elevator, he is producing CO2 and radiating body heat via IR. This excess heat introduced to the atmosphere within the elevator is removed easily by the ventilation fan, which draws out heat at a constant rate. (Similar to heat dissipating heat out to space. Ever been in a crowded elevator? When you increase the number of occupants inside the elevator, more people equates to more radiation of body heat, and more emission of CO2,(analogous to increased combustion of fossil fuel), and the ventilation are unable to ventilate the elevator as efficiency. You can place a vat of CaOH to remove all the CO2 in the air, but the elevator will still remain hot and stuffy. Since CO2 is a byproduct of heat liberation, it should be perceived as an indicator of warming, rather than a causative agent of warming. I agree that CO2 is a GHG, but its effects are overrated. If you think that an increase in a slight percentage of atmospheric concentration of CO2 can bring about climate change (despite the doubling, it is still at around 0.3% atmospheric concentration, remaining more or less constant), then why not the idea that the small amount of AWH generated can actually be a more important factor in causing warming than CO2? And if you want to argue about greenhouse gases being responsible for drastic warming, why is everyone ignoring the presence of the 80% atmospheric concentration of nitrogen, which is also a greenhouse gas? Should 80% of a greenhouse gas be more significant than 0.3% of greenhouse gas? Compared to nitrogen, the decimal percentage increase of CO2 can be regarded as negligible. In the previous thread, people have been likening AWH to a cracker and GHG as icecreams, and their effect on weight gain. It is important to realise that what actually brings about a change is the presence of a non-constant factor. If your staple food consist of eating 2200 calories of icecream daily, without any gain in weight, and put on weight only after eating a 50calorie cracker, it is actually the cracker which causes the weight gain, as it is a deviation from the existing equilibrium. The output of the sun has been more or less constant, while man's energy consumption has been increasing steadily, and shouldn't the warming be attributed to this rise in energy consumption? Referring to another analogy on this thread, while a candle may not hit up the room fast enough, a furnace may. Man's energy consumption has grown from a "candle" into a "furnace", and it is this massive increase in energy liberation that accounts for the drastic rise in temperature of the room, which remains as a constant, not changing in its dimensions. And lastly, the example of a nuclear plant is a highly relevant and interesting one. If CO2 is responsible for warming, why does nuclear plants, which does not produce CO2, still emits waste heat that serves to heat up the surrounding air? The only way to reduce warming, is to increase energy efficiency, so that less energy is wasted for the unintentional heating of air.
  16. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    A bunch of anti-AGW papers are linked here, if you're not already aware of the page.
  17. 10 Indicators of a Human Fingerprint on Climate Change
    New Boy. Concluding that CO2 is "the principal cause of the current warming" is a result of two processes. One. Physicists and chemists identified the properties of CO2 and advised (and then warned) that increasing the proportion of CO2 in the atmosphere would result in warming. Two. Other people have done lots of work on analysing all the various causes and sources of both warming and cooling now and in the past. Having measured, analysed, checked and analysed yet more data, they've concluded that the other known causes of variations in the climate cannot account for the current warming. The properties and the increasing concentrations of CO2 can explain it. One - theory about ghgs predicted warming long before there was any real evidence. Two - measurements of warming coincided with other measurements, greenhouse gases, TSI, volcanoes, declining ice, orbital variations, and found that only greenhouse gas warming can account for the increases we've seen.
  18. CO2 – Some facts, figures and outcomes
    Hang on. If there is enhanced photosynthesis activity due to enhanced CO2, shouldn't such plants produce more oxygen as the by product of all this. The last I knew, oxygen was declining as a proportion of atmospheric gases. Not enough to affect oxyden dependent life forms given its superabundance, but enough to back up the analysis based on carbon isotopes.
  19. CO2 – Some facts, figures and outcomes
    24. DB: The Caldeira papers disregard the enhanced photosynthesis and its effect on carbon dioxide levels. These papers are talking primarily about temperatures, whereas my original point 19(b) was about carbon dioxide levels. Maybe readers should study the second link in 22 above and some of the papers listed at the foot thereof.
    Response:

    [DB] I am more widely read than is supposed.  Perhaps others will gain some insights into your position from this quote:

    "volcanic CO2 emissions are much higher than previously estimated, and as volcanic CO2 is isotopically identical to industrially emitted CO2, we cannot glibly assume that the increase of atmospheric CO2 is exclusively anthropogenic."

    Plant regrowth & sequestration of CO2 is also directly affected by precipitation levels, which are also affected negatively by rising temps.  The net effect is reduced transpiration and slowed forest regrowth.

    Edit:  CarbonSkeptic has since revealed himself to be a sock puppet iteration of Doug Cotton.  It is unfortunate that some feel the need to falsely portray themselves as others in order to advance an agenda of pretence and active disinformation.

  20. CO2 – Some facts, figures and outcomes
    CarbonSkeptic - If you think the current surface temperature is due to heat transfer from the Earth's core (as you seem to state in that post), I suggest you read Heat from the Earth’s interior does not control climate. If you feel that is the case you should comment there. It turns out that heat from the Earth's core is several orders of magnitude too small to account for Earth's current surface temperature. Whereas greenhouse gas effects are just about right.
    Response:

    [DB] I suspect our guest has much in common with Mr. Cotton.

  21. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    Your statistics show one peer reviewed paper by Hans Labohm. According to the journal itself it is an opinion and i can not imagine that this is peer reviewed. http://ojs.ubvu.vu.nl/alf/issue/view/16 Would be strange as he is and economist and not a scientist.
  22. CO2 – Some facts, figures and outcomes
    23: I am very much aware of the physical properties of the carbon dioxide molecule and the quantum physics associated with it and other air molecules. I am also very much into heat transfer theory and thus understand the errors which, in effect, double count heat transferred from the surface. And, yes, I can explain Earth temperatures based on physics and the rates of heat transfer from the core to the surface and thence from the surface to space. In fact the calculations are within a couple of degrees of actual and do not relate to carbon dioxide at all. But you changed the topic and so, yes, I will answer elsewhere when I have the time.
    Response:

    [DB] "I can explain Earth temperatures based on physics and the rates of heat transfer from the core to the surface and thence from the surface to space."

    and

    "In fact the calculations are within a couple of degrees of actual and do not relate to carbon dioxide at all."

    It is rather odd, one would think, that you share both the unsupported energy transfer/CO2 hypothesis' of Doug Cotton as well as certain other characteristics...

    "I will answer elsewhere when I have the time."

    We look forward to you supporting your assertions with links to cited sources found in the peer-reviewed literature...on the appropriate threads.

  23. CO2 – Some facts, figures and outcomes
    22 DB: I'm sorry, but whilst I did read the blog "Planting Trees Won't Help" I would prefer to believe peer-reviewed papers such as those quoted in the link I provided. I fail to see any quantification in your item. Also, I was talking about carbon dioxide levels, not the effect on temperature based on the relative colour of the trees or the amount of evaporation.
    Response:

    [DB] "I would prefer to believe peer-reviewed papers"

    Perhaps this or this by Caldeira, for starters.

  24. CO2 – Some facts, figures and outcomes
    #22 CarbonSkeptic, it's hard to trust your assertions on deforestation when you're wilfully ignorant of the basic physical properties of the CO2 molecule. Perhaps on an appropriate thread you could explain to us us why the Earth has been liveably warm through geological history despite the Sun not presently provide enough incident radiation to keep Earth above freezing (without non-precipitable greenhouse gases), and even more so having been even fainter in the geological past?
  25. Human CO2 is a tiny % of CO2 emissions
    This is a dramatic oversimplification of factors affecting carbon dioxide levels. Relatively small percentage variations in natural "absorption" rates can overshadow all human fossil fuel output in either a positive or negative direction. To say "However, natural CO2 emissions (from the ocean and vegetation) are balanced by natural absorptions (again by the ocean and vegetation)" is simply a statement without proof. Such conclusions totally ignore the impact on the level of photosynthesis which is in turn affected by the quality of plant life, that in turn being affected by the level of carbon dioxide. Removing the natural carbon sink found in forests, for example, has been shown to have about four times the effect on carbon dioxide levels than that of fossil fuel emissions.
    Response:

    [DB] Link to off-topic website snipped.  Please endeavor to stay on-topic to the subject matter of the thread on which you are placing comments.

    Please note that posting comments here at SkS is a privilege, not a right.  This privilege can be rescinded if the posting individual treats adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Please take the time to review the policy and ensure future comments are in full compliance with it.  Thanks for your understanding and compliance in this matter.

  26. CO2 – Some facts, figures and outcomes
    18, 20 & 21: I am not talking only about carbon emissions from deforestation and forest degradation. Plant life enhances the rate of photosynthetic sequestration, and thus a reduction in plant quantities will (other things being equal) reduce the amount of carbon dioxide taken from the atmosphere by plant photosynthesis. Fortunately, increased carbon dioxide in the atmosphere enhances plant life such that photosynthetic sequestration is also enhanced. There are a number of papers but this will do for a start. My point in 18(b) is quantified in the literature referred to in this summary. There it is calculated that anthropogenic fossil fuel emissions account for only about 20% of the total anthropogenic contribution. Hence mankind should be focussing on planting forests more so than cutting fossil fuel emissions. Take it or leave it. In my view the carbon dioxide has no effect on warming anyway.
    Response:

    [DB] "Hence mankind should be focussing on planting forests more so than cutting fossil fuel emissions. "

    Hence the need to actually read more of the literature on the subject.  Like that from scientist Ken Caldeira:

    Planting Trees Won't Help

    "In my view the carbon dioxide has no effect on warming anyway."

    Perhaps in your world then the radiative physics of anthropogenically-derived CO2 differs from that already in the carbon cycle.  How wonderful.  For those of us in this world it is a different story.  Please note that unsupported assertions lacking source citations are generally ignored or treated as spam.

  27. new boy on the block at 14:26 PM on 3 November 2011
    10 Indicators of a Human Fingerprint on Climate Change
    i am new to the debate and if my point has been covered elsewhere i would appreciate a link. do we sufficiently understand the driving forces behind the cycle of ice ages and subsequent warming to state categorically that co2 from the burning of fossil fuels is the principal cause of the current warming?
  28. CO2 – Some facts, figures and outcomes
    Carbon S#19 Here's evidence. van der Werf et al 2009: carbon emissions from deforestation and forest degradation have been estimated to account for about 20% of global anthropogenic CO2 emissions That appears to be an average; the most recent estimate shown in Figure 1 in that paper was for 2006: Deforestation ~1.5 Pg C/yr, fossil fuels ~7 Pg C/yr. It's good practice to substantiate one's commentary - especially if you're interested in building credibility.
  29. CO2 – Some facts, figures and outcomes
    Carbonskeptic. The evidence is from carbon isotopes (not to mention some basic accounting). Deforestation is another anthropogenic change, but again the isotope data says fossil fuel more important. See this article for more detailed explanation and references to the science.
  30. Climate's changed before
    lancelot: it is not easy to measure surface radiation fluxes well. Last I looked, a system that will meet BSRN guidelines will cost you around $100k in equipment and sensor costs. BSRN is intended for long-term climate monitoring, and accuracy requirements push modern technology. If you want a very long read (and want to download quite a few megabytes of manual), the BSRN web site has a link to their Operations Manual. (Don't click the link unless you want the full manual!) Be prepared for a huge whack of technical discussion of sources of error, but before anyone decides "we can't measure radiation" keep in mind that the BSRN goals for accuracy are set very high (in the 1 W/m^2 range). It's the Rolls Royce of radiation measurement, not the Chevrolet version. It's part of the Global Energy and Water Experiment (GEWEX), and has been designated as the radiation observing system for the Global Climate Observing System (GCOS). Sphaerica: Please don't try to tell me that it can all be done by satellites. They give great spatial coverage, yes, but accuracy of surface radiative fluxes can't come close to good surface-based measurements. BSRN provides data at one-minute intervals, 24 hours per day, 365 days a year. A literature search for BSRN references will probably provide you with mostly satellite papers, all desperate for good ground-truth data.
  31. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    It would be worth clarifying that Jo Nova's real name is Joanne Codling (perhaps in her hyperlink?), as presumably she wouldn't be able to use her stage name in a peer reviewed journal :)
  32. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    Here is one that you can remove. The one publication linked to William Kininmonth is a Heartland Institute paper. How does that qualify as being from a peer reviewed scientific journal? The link is hosted by the Australian Climate Science Coalition, an Australian climate denier group. From Sourcewatch. The Australian Climate Science Coalition (ACSC) is a climate change skeptics website created by the the Australian Environment Foundation (AEF), a spin-off group created by the the corporate funded think tank, the Institute of Public Affairs.
  33. Climate's changed before
    lancelot#255, quoting Tom C#243: "More importantly, it is far from clear that this is a global phenomenon." Alpert et al 2005 supports Tom's observation: we show that this phenomenon, widely termed global dimming, is dominated by the large urban sites. The global-scale analysis of year-to-year variations of solar radiation fluxes shows a decline of 0.41 W/m^2/yr for highly populated sites compared to only 0.16 W/m^2/yr for sparsely populated sites (<0.1 million). Since most of the globe has sparse population, this suggests that solar dimming is of local or regional nature. Move over Urban Heat Island, here comes the Urban Dim Island!
  34. Pielke Sr. and SkS Dialogue Final Summary
    Rob@59 I'm not sure why you think the processes in the post How Increasing Carbon Dioxide Heats The Ocean (your link has an extra " at the end) contradict what vitull has said: - radiation reaches the surface from the atmosphere. Visible light will penetrate the water surface and be absorbed at depth, while IR will be largely absorbed right at the surface. (Energy gain to ocean) - visible light will be (partly) reflected at the surface and at depth, and IR will be emitted upward at the surface. (Energy loss from ocean) - turbulence in the atmosphere will carry heat and water vapour either towards or away from the surface (mainly away). This is convective transfer (in normal physics-speak). (Water vapour represents energy because it takes energy to evaporate the liquid). - turbulence within the ocean will transport heat away or towards the surface. This is convective transfer. - the viscous layer at the immediate ocean surface that is discuss in the other post does not have turbulence, but that is where conduction plays a role. Conduction can be up or down, depending on conditions (local gradient), but would be predominantly upward (from ocean depth to surface). Have I left something out? All these fall into victull's "radiation, conduction, and convection". I'd agree that the dominant global, long-term mean source of energy addition into the ocean is radiative, but on a local time-dependent scale, you can have net radiative loss to the atmosphere (e.g. at night), turbulent transfers from the atmosphere as net gains (warm humid overlying air, with condensation), and heat conduction across the viscous layer directed downwards. Perhaps you took victull's statement as one indicating long-term averages, as opposed to my interpretation of it as a general statement of possibilities? Perhaps my comment on the surface energy balance in that post is useful.
  35. CO2 – Some facts, figures and outcomes
    You say "The largest source of increasing CO2 in the atmosphere since 1850 is from the burning of fossil fuels ..." I ask what evidence you have that (a) such increases are larger than natural increases and (b) such increases are larger than increases due to deforestation which not only adds CO2 from burn-offs but also, far more so, from the resulting reduction in photosynthesis.
  36. Fred Singer Denies Global Warming
    A week ago the British Politician Roger Helmer, Member of the European Parliament and climate skeptic posted the email from his 'good friend' Singer on his blog; http://rogerhelmermep.wordpress.com/2011/10/27/the-scientific-finding-that-fails-to-settle-the-climate-change-debate/ I felt the need to comment, and still am.
  37. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    2, Gringo, I'd guess that the error would more likely be an editorial one than one of review. That is, review probably incited the new version of the paragraph, but then whoever edited the text mistakenly inserted the new paragraph and forgot to remove the old. A pretty harmless, human mistake, IMO.
  38. Berkeley Earth Surface Temperature Study: “The effect of urban heating on the global trends is nearly negligible”
    Lancelot @29, you specifically ignore the first, and rapid decline from 1800 to 1815. To the extent that that represents a signal in global temperature rather than an artifact of the limited regional coverage, it is likely that that decline comes from an even higher peak prior to 1800. That is because the Dalton Minimum, the presumed cause of the decline, began in 1790, and followed a peak in solar activity (as determined by sunspots) greater than any in the 20th century other than 1950. Consequently, the presumption of your first post of "a gradual and fairly uniform (if smoothed) global rise from at least 1800* to 1939". The evidence from BEST is of a major temperature excursion early in the record followed by a gradual rise from 1850 to 1910, followed by a rapid rise to 1940, a steady declind to the 1970's, and then a still more rapid rise to the 2000's.
  39. CO2 measurements are suspect
    MewCat100 @45, your point (4) lacks clarity. CO2 is approximately evenly distributed with altitude by concentration, as you note in (5). We do not need to reason that out, but can consult actual measurements: C)2 concentration with altitude, Colorado USA: Seasonal variation of CO2 concentration, Russia: CO2 concentration in upper troposphere and stratoshpere: (Click on images for more detailed discussion) However, the small changes of CO2 concentration with altitude are not enough to induce the temperature variations with altitude. They are primarily a function of convection which induces the environmental lapse rate. This is modulated by relative humidity, and by winds which can bring warm or cold air in from other locations. I do not see,however, what this has to do with the question posed in the OP's title.
  40. Is there a case against human caused global warming in the peer-reviewed literature? Part 1
    Regarding Energy & Environment's review process (or rather lack thereof), David C. Archibald's "Solar Cycles 24 and 25 and Predicted Climate Response" (PDF) is a good example. At the top of its page 31 there are two paragraphs which are almost identical and where the author clearly forgot to delete either of them. If the paper was reviewed at all, let alone by qualified reviewers, surely that double paragraph would have been spotted by someone? Or am I too naive to believe a 'scientific journal' which claims to "act as a forum for constructive and professional debate" should spot and correct such basic errors?
  41. Climate's changed before
    Lancelot -"In China one would expect a decrease in net irradiance received due to aerosols. I will have to take your word that the paper describes a decrease in actual sunlight hours since 1974, as I don't have access to it" There are numerous papers freely available on the topic. Try Google scholar. The indirect effect on aerosol formation is not what most people may think. In extremely polluted areas the sulfate particles reach a break-even point and start to warm clouds so much they begin to evaporate. This is small relative to the dimming effects, but it is a saturation point of sorts.
    Moderator Response: [Sph] Google scholar = http://scholar.google.com, a useful tool for searching specifically for scientific papers by keyword, author, and date range.
  42. Fred Singer Denies Global Warming
    Milka: You are wrong when you say "no-one denies the link between tobacco and lung cancer anymore" Dr Richard Lindzen (the climate skeptic from MIT) has testified in court that there is no link and maintains that argument today. this is the company the "skeptics" keep.
  43. Climate's changed before
    256, lancelot, No worries! I appreciate the interest in the science! The main point is that the science now is all about microbes and potential impacts on cloud formation, but there are no signs whatsoever that this translates into any effect on global climate, let alone a non-negligible warming effect related to current climate change. That's just a big leap, that isn't warranted by the state of the literature. From the article you linked to (emphasis mine):
    These data add to a growing body of evidence that biological organisms are affecting clouds, notes Anthony Prenni of Colorado State University in Fort Collins, an atmospheric scientist who did not participate in the new studies. Right now, he cautions, “We still don’t know on a global scale how important these processes are.” But research into microbial impacts on weather and climate is really heating up, he adds, so “within a few years, I think we’re going to have a much better handle on it.”
    So it's very interesting, yes. So are any number of avenues and subjects on which the media has yet to report. But it's of no interest in climate science (to me, at least) at this time. It's about weather, not climate.
  44. Climate's changed before
    Ah, page 6 now.. apologies for missing the latest posts when I wrote 255. Sphaerica, I am not trying to put down scientists, and I am sure you have even thought about fairies! But I have not been able to find any consideration of micro-organisms/clouds in the IPCC reports, and there are some interesting papers on the subject, such as http://www.wired.com/wiredscience/2011/05/microbes-make-rain/ Hence my question. I note the difficulties with making ground level (or sea level) measurements. Thanks again.
  45. Climate's changed before
    Tom Curtis 243; Could I add: You wrote: "More importantly, it is far from clear that this is a global phenomenon. Certainly in China the trend has been in the opposite direction towards less sunlight hours. A similar reduction of sunshine has been found in Switzerland, so the observed increase in the UK is not even a Europe wide phenomenon, let alone a world wide phenomenon." The Swiss study abstract quotes "general decrease of sunshine duration through to the mid 1980's". That doesn't seem so far off from the general decrease to around 1979-83 on the Met Office chart. (Just eyeballing here). Some data divergence perhaps due to varying definition of 'sunshine' measurement? So perhaps some common ground UK-Swiss? In China one would expect a decrease in net irradiance received due to aerosols. I will have to take your word that the paper describes a decrease in actual sunlight hours since 1974, as I don't have access to it. DB: Wow!- thanks for the Wild 2009 copy, really kind of you.
  46. Climate's changed before
    Lancelot -" Is that because readers are much too kind to lambast me for my stupidity in thinking that the airborne biosphere might(repeat might!) have a part to play in climate?" There is a considerable literature on the biogenic aerosol effect (naturally-occurring particles such as pollen, sea salt, leaf fragments etc seeding cloud formation). I've read a lot of papers on aerosol formation in the Amazon rainforest region, for starters. What is it you think they (biogenic aerosols) are doing? And how do you come to the conclusion the IPCC doesn't know about the published scientific literature?
  47. Climate's changed before
    250, lancelot, I mentioned aerosols because your point is not about cloud forcing (whether you realize it or not), but about total solar radiation received at the surface. You are presuming that cloud cover changes are a possible and likely cause (less clouds = more sunlight = more warming). You are then taking it a step further and saying that well, okay, it may not be GCRs, but maybe it's something else. That's magical thinking. That's hoping to find a cause, and then after the fact looking for a cause of the cause. More to the point, I included aerosols because they can have the same effect as clouds, by reflecting incoming sunlight. Indeed, Hansen proposes this for a reason that warming is not as great as it should be. It's also a reason that the loss of the Glory satellite was a big blow to advancing climate science. But a decrease in such reflective aerosols (due, for instance, to improved pollution controls) could in the same way raise temperatures. Aerosols (depending on the type) can also have the opposite effect, by absorbing more sunlight and increasing warming, so an increase in such aerosols could warm the earth. The point is that scientists are not stupid. They are looking at all of these things and giving them their due. On micro-organisms, stony silence and kindness concerning stupidity... ummm, sorry, sort of. When you mentioned it I did look into it, and there do seem to be some very, very interesting papers on the subject of micro-organisms and their impact on cloud formation. But I honestly didn't think for a moment you were serious about it. But... while this is an area of interest to the scientists working on it, as of now: a) There is no strong, well-defined or reasonably serious mechanism that turns micro-organisms into a major player in changes in cloud formation in the last 30 years. b) More importantly, no change in micro-organisms has been identified or even proposed that would suggest that something has happened in the last 30 years to trigger warming. Again, it's a case of hunting for an alternate cause when there is no reason to do so, and then in turn still needing to find a cause of the cause. Could it be clouds? We have no reason whatsoever to think so (and don't think scientists have not been measuring cloud cover, they have). Could it be clouds caused by micro organisms? We have no reason whatsoever to think so. Could it be clouds caused by falling fairy wings, as a result of an unexpected increase in the desiduous-winged fairy population? We have no reason whatsoever to think so. [Sorry if that last sounded snarky. It wasn't meant to be. It was meant instead to show that science must work by going from observation to hypothesis to experiment to confirmation/refutation. And can not work simply through "but what if..." followed by any and every idea that anyone could consider, simply because they don't like the ideas that we do have, for which we have evidence, and which logically and consistently explain the entire picture without the addition of fairy wings.]
  48. Richard Milne separates skepticism from denial
    Ian @57, Guess who is McKitrick's BFF? Yes, Steven McIntyre.
  49. Climate's changed before
    250, lancelot, Measuring energy received at the surface may seem straightforward, but as I said before, it is most certainly not. You must account for: 1) Local, low lying and potentially transient effects (smog, fog) 2) Coverage... how do you do it on the oceans, which cover 70% of the earth? Deserts? Inhospitable countries? 3) Altitude... radiation will be higher for measurements taken at higher altitudes 4) The past? How do you know what happened before you get your network set up? To what do you compare your new values? All of the problems that plague the observational surface temperature record apply as well to measuring sunlight. It's just not as easy as it sounds, especially when a satellite can do that and more for less money with less effort and more consistency.
  50. Climate's changed before
    250, lancelot, To clarify, however, the references to clouds in the AR4 do not give any credence whatsoever to the idea that changes in cloud cover are responsible for the modern warming trend. This is in no way believed or expressed. The references to clouds in AR4 pertain explicitly to positive feedbacks and climate sensitivity, i.e. given warming X from CO2, how much additional warming Y will be added to that from clouds. AR4 (and scientists) are very upfront about admitting to this area of doubt in predictions, and adjusting error bars appropriately. But the admission is one of mere prudence and honesty, and part of the reason that the currently accepted range of climate sensitivity is between 2˚C and 4.5˚C per doubling of CO2. Part of the reason for that wide range (2.5˚C total) is due to uncertainties about the effects of warming on clouds, and the corresponding effects of changed clouds on warming (although there are other factors, too).

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