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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 97751 to 97800:

  1. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    I don't know, there have been some pretty impressive predictions made by climate modelling over the years, like the one in this Skeptical Science post. They tend to be longer-range forecasts, so a lot of the predictions made in the past decade or so wont be realised for some time to come. Of course, you could always take the approach that, so far, climate science has tended to underestimate the rate and impacts of global warming...
  2. Rebuttal to 'Scientist's Can't Even Predict The Weather Right'
    I haven't yet come across a technically educated skeptic that uses this argument. However, I have heard it from non technical people. Actually, I'm generally surprised at how accurate weather predictions are. I wish the climate models could match this accuracy.
  3. Seawater Equilibria
    #31 you asked what effect organic carbon has. Fair enough question. Here is my rough answer at the question Dr Franzen has avoided for reasons of space I assume. The answer is complicated. Multiple cycles are at work in the ocean. For the AGW deniers who want to excuse increases in CO2, looking at the organic carbon in ocean life does not help them. The slow addition of calcium bicarbonate (from calcium silicate minerals) and other minerals by weathering (historically the major process) involved in the drawdown of CO2 into ocean sediments have been vastly exceeded by the fossil fuel CO2. Looking at the Paleo record the CO2 peaks go up quickly and down very slowly. The drawdown of CO2 by life in the oceans had a large historical example. The Azolla Event 49 million years ago, is thought to mark the end of the Hot House Earth and lead to the start of the glacial cycles. It took 800,000 years. Even in optimum conditions like the Azolla Event life is not quick at drawing down CO2. Azolla Event We will need to manage ocean pH sooner or latter due to poor CO2 level control in the atmosphere. Any idea that just adding alkali will fix the oceans needs to be quickly dropped. Aquarium keepers are already doing this on a tiny scale and the below is to help shine a light on what it takes to keep salt water at a healthy pH 8.2 to 8.3 for tropical species. A short answer to your question is the effect of healthy life in the ocean seems to be to add to the alkaline buffer strength. This seems to be because life increases the species that can bind to a H3O+ ion. My reference for this is: marine aquariums The aquarium keepers have a challenge with keeping stable pH in salt water aquariums as the complex cycles that are in the oceans are not present. The buildup of fish waist quickly turns acid. Attempts to gain good pH control by just adding calcium carbonate or bicarbonate powder just work for a few days as the pK of the buffer shifts to 7.6 and away from the sweet spot of 8.2-8.3 for tropical creatures. The salt aquariums challenge to get stable pH is achieved by adding the complex mixture of buffers that are similar in their levels to the ionic species found in the oceans. commercial aquarium product marine aquariums pH control The shortest answer to the problem of ocean acidity it seems to me is that the oceans ability to absorb CO2 is coming to an end as evidenced by the rise in average pH of the oceans, so quickly limiting the use of coal, oil and gas, till atmospheric CO2 is below 350 ppm is the most direct solution.
  4. Monckton Myth #6: Global Sea Ice
    Daniel Bailey: "There was a time when I thought I could convince you using the scientific method and peer-reviewed primary sources." GC's been a die-hard denialist from the beginning, and while it's a good idea to give the benefit of the doubt for a few posts, there's no reason to do so over periods of months or years. At some point, the truth's out, and that point's been long passed by GC.
  5. Monckton Myth #6: Global Sea Ice
    Galloping Gish Camel:
    Those folks (e.g. the IPCC and the NSIDC) who predicted a dramatic decrease in Arctic ice by assuming that the trend that gave us a record low ice coverage in 2007 would continue have been shown to be wrong (color them "Alarmists"). Here is some information on Arctic ice in a region that has some economic importance (at least to the Russians)
    followed by:
    You make the all too common mistake (at least on this blog) of refuting imagined statements. I am convinced that the climate is indeed warming. You won that argument as we happen to be on the same side of the issue.
    You posted your reference in order to support your claim that "Those folks (e.g. the IPCC and the NSIDC) who predicted a dramatic decrease in Arctic ice by assuming that the trend that gave us a record low ice coverage in 2007 would continue have been shown to be wrong" An anecdotal cherry-pick which, as it turns out, doesn't support your claim. Quit whining.
  6. A Flanner in the Works for Snow and Ice
    #9 LandyJim "around 90% of the south is a frozen continent" Yes but Antarctica is covered mostly with ice as opposed to the northern hemisphere where you get substantially more dark surface area (both land and water) to absorb incoming radiation.
  7. CO2 effect is saturated
    Re: Colin Bridge (74) Hey, welcome to Skeptical Science! Thanks for posting your first question on an appropriate thread! Your friend's article is incorrect in many respects: 1. Even if the absorption band of carbon dioxide would be fully saturated in the lower parts of atmosphere, it is not saturated in higher atmosphere and the addition of carbon dioxide (CO2) will cause more absorption of thermal radiation (extra CO2 has extra effect for a multitude of reasons). Nice-to-know: CO2 exerts its effects primarily though bending mode (you can see visualizations of the various modes of CO2 here). As shown there, CO2 is infrared (IR) active due to a transient dipole: bending results in charge being asymmetrically distributed with net positive near the carbon atom and negative near the two oxygen atoms. 2. Water vapor is a condensible GHG. Short-term increases in concentrations of it condense out and equalize in about 9 days time. CO2 stays aloft for centuries-to-millennia. Like the Energizer Bunny, it keeps on doing its thing. 3. The Earth currently takes in more energy than it emits. We can physically measure this. This emission takes place at the Top Of Atmosphere (TOA), well above where water vapor has anything but a minimal effect (it is found in only trace amounts there). Only the increasing concentrations of CO2, which we can isotopically tell come from fossil-fuel emissions, explain the imbalance. And they explain it quite well. Turning up the CO2 control knob is like cranking up the thermostat to max...and breaking it: The NOTES section at the bottom of this page contain much useful material. Also see here for background on the greenhouse effect and the 2nd Law of Thermodynamics, which usually comes in the next contrarian article. :) BTW: The introduction of N2 and O2 is a complete red herring, as they are unaffected by infrared. Hope that helps. The Yooper
  8. Monckton Myth #6: Global Sea Ice
    Re: gallopingcamel (32) You are mistaken, sir, when you attribute that graph by the moderator to me. It lacks my name attached to the Moderator Response box (which I always provide to avoid confusion such as this). But since you have dragged me unwillingly into this:
    "This thread is over reacting to Monckton pointing out that Antarctic ice extent is growing."
    Incorrect. This thread is about Monckton's claims of "The global sea ice record shows virtually no change throughout the past 30 years".
    "On this site there is a fixation on "Warming" evidence while the reaction to contrary evidence is to ignore it or "Attack the Messenger". This approach repels the very people you are trying to convince."
     Skeptical Science relies upon using the peer-reviewed primary literature as well as the scientific method to examine the various claims out there to separate the chaff from the wheat. Claims that are unsupported by the available evidence that fits this criteria do tend to get ignored. As you are well aware, claims that are intended to overturn centuries of evidence accumulated during the lifetimes of thousands of scientists are therefore extraordinary, requiring an even higher level of extraordinary evidence that is supported by primary literature that withstands scrutiny in the peer-review process. None of which you have been able to provide to substantiate past claims you have made. There was a time when I thought I could convince you using the scientific method and peer-reviewed primary sources. That ended when you falsely accused me of dishonesty, an accusation you have never retracted. In your case, I now limit myself to pointing out your errors with links to sources documenting the correct way forward for the sake of posterity and the lay readership, who may read these threads at some unknown future point. I have no expectation or hope whatsoever of you ever becoming a resource here.
    "The graph that Daniel Bailey appended to my #29 was included in that document (Figure 13 on page 30). If you look closely you will find that the sea ice range predicted for the year 2100 dips to zero."
     Again, not my graph. The range you refer to is the width of model runs, the lower bound of which nears zero in 2100. Applying a quadratic fit to actual observations shows sea ice extent approaching zero about 2030. Your remaining comment about snowfall is off-topic here. The Yooper
  9. apiratelooksat50 at 14:26 PM on 24 January 2011
    Could global warming be caused by natural cycles?
    Muon @ 176 "I show you peer-reviewed research that 'suggests' changes to el Nino are based on AGW; that 'confirms' that human activity can and does alter global phenomena." How does one go from taking research that "suggests" a hypothesis to "confirming" your opinion?
  10. A Flanner in the Works for Snow and Ice
    A question and two comments. The paper finds a much greater albedo rise than expected compared to from models for the amount of warming experienced. However, my understanding is that warming in at latitutude 60+ north has been greater than expected. How does the albedo change in those latitudes compare to the models of the basis of temperature? Ie, in the models, if you correlate albedo change at 60+ north to temperature at 60+ north rather than global temperature change, is the relationship as expected or stronger? As to the comment, at least some of the excess warming in northern latitudes has been because of the Atlantic Multidecadal Oscilation. Some also has been due to the enhanced greenhouse effect, and some due to the loss of albedo driven by the other two. It is not certain as to the relative strengths of the first two (AMO and GHE), so it is not certain how much this study supports a higher climate sensitivity. If, for example warming effect of the AMO in northern latitudes has been twice that of the enhanced GHE, then the models have got the albedo calculations close to correct, but nature is conspiring against us. If, on the other hand the AMO warming is half that of the enhanced GHE, then the models are significantly underestimating climate sensitivity. Finally, although this result may be very significant for estimated in climate sensitivity in models, it is irrelevant for estimates based on observations. Those, of course already included all the detailed changes in the final output without knowing what they are. So regardless of the implications of this study, we should still be expecting a climate sensitivity of around 3 degrees per doubling of CO2.
  11. The Climate Show #5: Green roofs and Brisbane floods
    Was the last flood in Australia worse than the floods of 1973-74? http://www.bom.gov.au/lam/climate/levelthree/c20thc/flood7.htm
  12. Monckton Myth #6: Global Sea Ice
    #34: Glenn, I think Ignorance is Strength is more SPPI's speed. Caught 'em once claiming that recent Greenland ice melt was due to a volcanic eruption. They hadn't noted that the volcano in question was 2200 years ago.
  13. Monckton Myth #6: Global Sea Ice
    And to the topic of the thread, which is about Monckton's track record in what he claims, his use of the comparison between Arctic & Antarctic ice is demonstrably false. However the bigger issue is the additional data that James and then others have posted here. Monckton is the 'Chief Policy Advisor' of the Science & Public Policy Institute whose Mission Statement begins: 'The Science and Public Policy Institute (SPPI) is a nonprofit institute of research and education dedicated to SOUND public policy based on SOUND science...' (my emphasis) More sound science has been presented here by a range of people doing it as willing amateurs, for free, than ever by Monckton who is PAID to do it. Unless of course expressions from Monckton and Co about 'SOUND science' should be interpretted in the Orwellian sense... ... War Is Peace.
  14. Water vapor is the most powerful greenhouse gas
    I am not a scientist but lived with a lot of observation in my life. Can someone tell me if many are actually missing the point and getting to technical? From my observation and reading many papers on line, it would seem that CO2 is far from the cause of global warming, Co2 is a result of global warming from what I can glean. So if water vapour is causing the the increase in temperature, then the increase in temperature is the cause of CO2 rises. To explain: It would appear that after a period of warming and even when the mini ice age came through, CO2 continued to rise to a peak before declining. It would appear that greater degeneration of plant life is caused through warming emitting faster quantities of CO2 into the atmosphere, this in turn creates greater growth of natural flora and fauna to again be degenerated and emitting greater flows of CO2. These growths are also as a result of increasing rains, and higher dew points. Research also shows without being specific, that in Roman times CO2 was higher then than now, that the global temperature was 3 degrees Celsius higher then than now and greater vapour was evident in some history books. If this is the case why are we being led to believe otherwise and that the planet is in danger of burning out if we do not get CO2 under control? I would just like to add as an aside , that Australia despite having serious rain problems and flooding this year, our harvest in South Australia has exceeded all expectations and 300,000 tonnes greater output than the highest ever record reached. As CO2 and water are a necessary plant food, could the small rise be sufficient to warrant awarding the increase to these two elements? Maybe we should be applauding the fact that we have this rise to create greater stock piles before it recedes to almost famine growth as it was in the 1950's with most of our water vapour again locked into glaciers and pole caps. Sometimes to much knowledge in one area can be detrimental to a whole picture which has not been formulated yet. Apologies if this has been addressed as I have not had time to read the many posts, yet!
    Moderator Response: Welcome to Skeptical Science! At the left of every page is a list of Most Used Skeptic Arguments. To see all of them, click the link "View All Arguments" at the bottom of that short list. You can also get there by clicking the "Arguments" link in the blue horizontal bar at the top of every page. You'll find the answers to all your questions there. For example, see "Water vapor is the most powerful greenhouse gas," "CO2 lags temperature," "Warming causes CO2 rise," "CO2 is not a pollutant," and "It’s not bad." There are more, but I'm tired of typing. Your best first stop, though, is the Home page, where you should click on the two boxes at the upper right labeled "Newcomers, Start Here" and "The Big Picture." By the way, one of the rules is that you must post comments on appropriate threads. This first comment of yours is too broad for this thread, but that's okay because this is your first time. But in future please find the best thread ("Argument") to post each comment on. And split up your comments into multiple narrow ones, one comment per topic and therefore one comment per thread. Also take advantage of the Search field at the top left of every page.
  15. Monckton Myth #6: Global Sea Ice
    GJ Too me the telling graph in James' post is the last one, the decline in multi-year ice. Add to this reports from researchers in the field in the last year that even that MY ice is pock-marked with holes that have been re-covered with 1st year ice. This is a picture of the backbone of year to year ice retention - structurally strong, thick MY ice in serious decline. As more of the Arctic Ocean is exposed in summer, winds are likely to be able to generate stronger waves and swells that can break up younger ice. As with land ice, it isn't just pure melt that matters but mechanical forces that cause break up and enhance melting. Interestingly, the MY ice isn't located around the Pole as one might expect. Where ice can survive longer is probably more influenced by weather patterns and ocean currents than absolute latitude So an 'ice free Arctic in Summer' well before 2100 looks highly likely unless current trends reverse rapidly - with one caveat. Rather than 'ice free' perhaps the correct expression should be 'effectively ice free'. There will quite probably be pockets of ice in the Arctic that persist through summer, depending on local weather conditions that year, and some years may be particularly cold and it doesn't clear at all. But in practical terms an effectively ice free summer arctic looks to be 10-20 years away Certainly in terms of the albedo impacts and trans-polar navigation.
  16. A Flanner in the Works for Snow and Ice
    Answering #9: Jim- How could any professional claim this paper is 'scaremongering'? It does not, as you accuse, assume all the ice turns into water without some also going to vapor. As the article says near the very top, it bases this conclusion on satellite measurements. So that it does NOT have to make any such rash assumption. The results of satellite observation do in fact confirm that not enough of the molten ice turns into clouds to offset positive feedback.
  17. Oceans are cooling
    Should also look at the excellent Science of Doom articles on back radiation and ocean warming
  18. A Flanner in the Works for Snow and Ice
    LandyJim #9 'Sorry to say this, but actually this paper will come across as scaremongering and incomplete science, they should have accounted for evaporation from the surface and estimated cloud cover to approximate the offset this would provide.' That criticism seems to me to be based on a rather simplistic view of how science works Jim. Much of science is based on researchers looking at small parts of a puzzle. This spurs others to investigate other parts. And what a research team looks at depends on their backgrounds, resources, budegt etc. To criticise some work because it didn't try to look at all aspects seems unfair. Others will do that over time. This paper is showing one result. Others will no doubt look into other aspects subsequent to this. Patience Jim
  19. gallopingcamel at 12:19 PM on 24 January 2011
    Monckton Myth #6: Global Sea Ice
    dhogaza (@31), You make the all too common mistake (at least on this blog) of refuting imagined statements. I am convinced that the climate is indeed warming. You won that argument as we happen to be on the same side of the issue. This thread is over reacting to Monckton pointing out that Antarctic ice extent is growing. On this site there is a fixation on "Warming" evidence while the reaction to contrary evidence is to ignore it or "Attack the Messenger". This approach repels the very people you are trying to convince. Michael Sweet (@30), Good point but I was not referring to AR4. The "Copenhagen Diagnosis" was published in 2009. The graph that Daniel Bailey appended to my #29 was included in that document (Figure 13 on page 30). If you look closely you will find that the sea ice range predicted for the year 2100 dips to zero. Personally, I am as skeptical of that prediction as I was about snowfall becoming a rare phenomenon throughout Europe. However, I applaud the IPCC for being bold enough to make itself clear on the issue.
    Moderator Response: I'm not attacking the messenger. I am attacking the assertion that Arctic sea ice decline is "matched" by Antarctic sea ice increase. As I've shown above, neither extent data, nor area data, nor volume data bear this out. - James
  20. A Flanner in the Works for Snow and Ice
    #9: "I would suspect the different is not as much as one might think." Great insight there, LandyJ. Did you miss that the paper actually measured this change towards additional warming? And that, by definition, takes into account evaporation? "has anyone done a study of how the unfrozen Ocean will now have surface currents ...I have searched and cannot find one." Seems like the Navy did some work on that over the years. Here's one: Hibler 1979: A Dynamic Thermodynamic Sea Ice Model In summer a low compactness region of up to 50% open water builds up off the Alaskan and Siberian coasts, in general agreement with satellite-derived ice concentration charts... So we can go with your totally unconnected, totally unscientific 'maybe unfrozen Ocean will now have surface currents' that will miraculously provide some unknown impact. Or we can go with those who are measuring what's actually going on. To quote that noted climatologist H. Callahan, "you gotta ask yourself one question: Do I feel lucky?"
  21. A Flanner in the Works for Snow and Ice
    @Ron Crouch, yes there is a lot of frozen land in the North, but the majority of the Polar region is a frozen ocean and that around 90% of the south is a frozen continent. I don't know the exact numbers off the top of my head, but I would suspect the different is not as much as one might think. In respect of the article...Air warms, Ice melts, some goes into the sky to make cloud..Oh hand on, I didn't read mention of that in the quoted paper..I get the impression they are assuming a total melt to liquid that defies the laws of thermodynamics and never evaporates. Sorry to say this, but actually this paper will come across as scaremongering and incomplete science, they should have accounted for evaporation from the surface and estimated cloud cover to approximate the offset this would provide. Also, has anyone done a study of how the unfrozen Ocean will now have surface currents that will flow different from today and thus have an impact...I have searched and cannot find one. The cold water in these currents may have a negative impact on the heat absorption, or it may have a positive impact too and exacerbate the problem. Yet more unconnected so called science of the modern era in my professional opinion.
  22. CO2 effect is saturated
    In an argument about this article a friend sent me this. Can someone help me with a layman's language rebuttal? **************************************************** "Water, a 3-atom dipolar molecule has several ways of rotating and several ways of vibrating, so it interacts with and absorbs electromagnetic radiation in many parts of the spectrum. It is a strong "greenhouse gas". Carbon dioxide is linear and symmetrical, so it has no resultant dipole and it therefore cannot absorb in the rotational frequency region. Its symmetrical stretching vibration is also infrared inactive. Its asymmetrical stretching vibration however produces a constantly reversing dipole, so it absorbs in a narrow band of frequencies around 2350 wavenumbers. Likewise the bending vibrations, around 670 wavenumbers. So in most of the infrared and microwave spectrum the molecule behaves just like N2 and O2. It doesn't absorb at all. It does absorb in two narrow frequency bands, and absorbs so strongly there that the present concentration of CO2 (about 340 parts per million by volume) achieves almost complete absorption. Increasing the concentration can cause only a little more absorption. The high extinction coefficients are known, the concentration is known, the calculation is not difficult abstruse or speculative, and I think you will agree that it is relevant to anyone who wants to write informatively about the greenhouse effect." ****************************************************
  23. OK global warming, this time it's personal!
    John, In case you like seeing your personal natural disaster from above, here's an ISS photo. Full scale available here.
  24. A Flanner in the Works for Snow and Ice
    New paper from CCNY 'cryocity' group, confirming that reduced snow/ice cover leads to decreased albedo, this time over Greenland: Tedesco et al 2010 Preprint -- Publication version Early melt onset, triggered by large positive near-surface temperature anomalies during May 2010 (up to +4ºC above the mean) contributed to accelerated snowpack metamorphism and premature bare ice exposure, with the consequence of rapidly reducing the surface albedo. Reduced accumulation in 2010, and the positive albedo feedback mechanism are likely responsible for the premature exposure of bare ice. See also the comment here for link to cryocity website.
  25. Greenland is gaining ice
    Beautiful website about Greenland ice loss. Remote sensing data, surface observations and models indicate new records in 2010 for surface melt and albedo, runoff, the number of days when bare ice is exposed and surface mass balance of the Greenland ice sheet. This was especially true over over its west and southwest regions. Anyone not see the trend? In simple words, each bar tells us by how many standard deviations melting in a particular year was above the average. For example, a value of ~ 2 for 2010 means that melting was above the average by two times the ‘variability’ of the melting signal along the period of observation.
  26. Zvon.org guide to RealClimate.org
    I just noticed that Realclimate now has a link to Zvon.org prominently in the right hand menu column. They obviously appreciate your efforts.
  27. A Flanner in the Works for Snow and Ice
    They only attempt to calculate the Northern Hemisphere component Krab. A Southern Hemisphere component would also need to be calculated. Obviously because the greatest bulk of land mass exists in the Northern Hemisphere that component will have a stronger signal than it's southern counterpart, so dividing by 2 doesn't provide an accurate picture. It will however allow for further refinements of both global and regional climate models.
  28. A Flanner in the Works for Snow and Ice
    I confess to being much confused by this post. How could W/m^2 for land be added to that for sea? Aren't they different areas? Going to the paper itself cleared this up. The total Watts are calculated and then divided by the total area of the whole northern hemisphere. This approach allows adding contributions together but still seems strange. Why not divide by the area of the whole earth? That way they could be directly compared with the other Global forcings. To make the comparison e.g. with the standard summary chart http://en.wikipedia.org/wiki/File:Radiative-forcings.svg, the northern contribution given above must be divided by 2.
  29. A Flanner in the Works for Snow and Ice
    @kdfv: No, why should it? It means that climate sensitivity is a bit higher and therefore 2*CO2 warms the planet more than previous thought.
  30. A Flanner in the Works for Snow and Ice
    Does this mean that the warming affect of carbon dioxide is less than thought?
  31. A Flanner in the Works for Snow and Ice
    To gain a little perspective on Arctic temperature and precipitation trends have a look at Climate Trends and Variations Bulletin - Annual 2010. Precipitation trends would tend to indicate that there should be no lack of snow cover in the immediate future. It's the extent depth/thickness and length of season that are changing subtly and amplifying the warming that is already taking place. If you look at the Annual Regional Temperature Departures we see a 63 year temperature record with the trends (relative to 1957). These temperature departures are well above global averages. The Mackenzie district experienced it's second largest departure while the rest of the Arctic districts experienced their largest. And if 2010 is any indication, then the Arctic will continue to get warmer. That's likely to have effects upon Arctic Ocean currents and atmospheric circulation patterns.
  32. A Flanner in the Works for Snow and Ice calculations
    I have yet to read the paper, but the press release quoted Flanner as saying that they found an ~+15% increase in TOA forcing. Is that consistent with your calculations? A ~20% sensitivity increase seems huge. Maybe run this by him? BTW, on a related topic I just happened to see this new paper (abstract), which got almost no attention when it came out a couple of weeks ago (I only saw it because of an article in a co-author's hometown newspaper) but sure seems like it deserves some. AFAICT (haven't read the paper) lack of prior data makes it a snapshot rather than a trend analysis, but even so the indicated change (~-25%!) to the land sink is not small potatoes.
  33. Oceans are cooling
    Folks, The discussion #43 - #51 on the penetration of temperature variation as a function of frequency is a well-known result of the heat equation. As a quick sketch, if you impose a sinusoidal temperature variation at the top surface of an infinite block, the temperature variation within the brick will also be a sinusoidal variation in the time variable, but the amplitude will die exponentially as a function of depth. The characteristic length for the exponential fade is proportional to the square root of the period of variation: L ∝ √Period. So the longer the period of variation, the deeper the temperature of variation reaches, so the greater the effective heat capacity or"thermal inertia" of this situation. Some references: Brief general discussion of the heat equation: http://mathworld.wolfram.com/HeatConductionEquation.html Start with eqn.2 and read to eqn.5. Unfortunately, they don't discuss oscillatory solutions: However, if you assume a positive separation constant in eqn.5, it becomes: (1/κ)*(1/T(t))(dT/dt) = (1/X)(d^2 X/dx^2) = 1/λ^2 Assuming T(t) = exp(iωt), and X(x) = exp(-λx), iω/κ = 1/λ^2 λ = sqrt(iω/κ) = √(ω/κ) * √i = √(ω/2κ) * ( 1 + i) Therefore the solution is: T(t)*X(x) = exp(iωt) * exp(-ix√(ω/2κ)) * exp(-x√(ω/2κ)) Taking the real part of the solution, we get: cos(ωt - x√(ω/2κ)) * exp(-x√(ω/2κ)) So this is a wave traveling downward at speed v = √(2κω), with angular frequency ω, and fading out with characteristic length L = √(2κ/ω) So the slower the frequency, the longer the cycle period, and the greater the depth of penetration. This solution applies straightforwardly to the brick, or to the ground. It applies to the oceans as long as they are not disturbed, so the layers are not mingled. If the layers are mixed, then the depth of penetration is increased; and the longer the period of the driving temperature variation, the greater the likelihood of mixing. So the application to the ocean still makes sense: The liquidity still supports the point that the greater the period, the greater the depth of heat penetration and thus of the thermal inertia.
  34. Dikran Marsupial at 08:06 AM on 24 January 2011
    Monckton Myth #4: Climate Sensitivity
    actually thoughtfull@37 I don't think the journals are feeling the pressure to publish papers that question AGW to the extent that bad papers are getting published because of it. Peer review is only a basic sanity check, so bad papers get published occasionally anyway. This is especially true when there is a heirarchy of journals and if your standards are low enough, your papers will get published regardless of how bad they are (the bottom end is little more than vanity publishing). However, even when they do get published, they don't generally attract many citations (other than in papers that point out the error), so looking at the citations is still a reasonable indication of whether a paper is of any value. There will undoubtedly be dodgy papers from mainstream climatologists as well, but you will be less likely to hear about them as they weren't preceded by a press release.
  35. Could global warming be caused by natural cycles?
    For those inclined to favor the AMO (Atlantic Multidecadal Oscillation), Tamino has a nice summary opinion on it:
    "The increase in AMO from 1975 onward is because the detrending (an attempt to remove the global warming signal) is linear, but the global warming signal is nonlinear. Therefore the AMO increase since 1975 is because of global warming. Using it, without detrending the 1975-present segment separately, is exactly the problem previously described: using the effect of global warming as the cause of global warming."
     and
    "the residue of the global warming signal in the AMO data gives the visual impression of a roughly 60-year cycle -- a mistaken idea for which there's no evidence other than wishful thinking on the part of denialists."
     and finally
    "It really comes down to another lame attempt to claim that some "natural cycle" is responsible for global warming. The cycle doesn't exist, the one you think you see is the residue of global warming in N.Atlantic temperature data. If you want to remove the impact of N.Atlantic fluctuations on global temperature, detrending the post-1975 AMO is the only way to do it right.]"
     I'd read a great deal lately on the AMO as a possible source for some of the observed warming in the NH, but this is (honestly) the best explanation of the AMO I've yet read. Or at least that I've understood. Good stuff. The Yooper
  36. A Flanner in the Works for Snow and Ice
    Good writeup, Mark. If these results are subsequently confirmed the upcoming Arctic melt seasons will get very interesting... The Yooper
  37. It's cosmic rays
    #37: Eric, Thanks for the link to the Veizer 2005 paper; it certainly is unusual. He's mixed together what we've called GCRs with solar cosmic rays into a 'cosmic ray flux' (CRF). The CRF, in turn, is believed to correlate with the low altitude cloud cover. The postulated causation sequence is therefore: brighter sun ⇒ enhanced thermal flux + solar wind ⇒ muted CRF ⇒ less low-level clouds ⇒ lower albedo ⇒ warmer climate. Who among us will argue with the endpoints of that logical chain? Yes, brighter sun -> warmer climate. However, nothing in either Veizer or Rao substantiate the postulated mechanism of the steps in between.
  38. Monckton Myth #6: Global Sea Ice
    GC:
    Here is some information on Arctic ice in a region...
    So your point is that the sea ice area in the sea of okhotsk is far below the 1979-2008 average, which ... disproves global warming?
  39. Eric (skeptic) at 07:18 AM on 24 January 2011
    It's cosmic rays
    #36, I just read through that paper and I don't see a quantification of the low cloud changes. I don't think the author divided the TSI fluctuation by 4. His figure (2) comes from this paper http://www.sciencebits.com/files/articles/GACV32No1Veizer.pdf The Veizer paper references this paper http://www.agu.org/journals/ABS/2002/2002GL015474.shtml which states "Correlation of our total irradiance time series with T accounts statistically for 80% of the variance in global temperature over that period, although the irradiance variation amplitude is insufficient to influence global warming in present-day climate models." I'm skeptical about this last paper, correlations are suspect and I have not seen correlations of TSI and GAT.
  40. A Flanner in the Works for Snow and Ice
    Nice analysis, Mark. Interesting, and somewhat worrying study.
  41. Medieval Warm Period was warmer
    Stefann, Oxford Kevin, Some time ago I went through as many of the co2science papers as I could bear. What I discovered was that: 1) Very many papers described a "medieval warm period", but differed from each other in actual dates by hundreds of years. Some would say 900, some, 1200, some 1400. Often there might be a period of some warmth for a few hundred years, but the period coming close to modern temperatures would be a peak covering a mere 20 span, and the peaks varied by hundreds of years from one study to the next. So the site will quote papers as seeing the MWP from 900 to 1250, and exceeding current temperatures by 1.5˚C, any yet the actual period where temps were that high were a mere couple of decades, and never the same couple decades from one study to the next. This would be the equivalent of taking the warmest annual temperatures from each country in the past three hundred years, and using each such maximum in concert to determine the temperature for the entire globe in that period. You couldn't even justify doing that in a single year, let alone ten, let alone hundreds. 2) I found several studies that were very selectively interpreted. For instance, one was based on a graph from a paper which showed warming in South American lake sediments. If you went to the paper, there were five other lakes in the study, all of which showed substantially cooler temperatures. They picked the one that showed extreme warmth and ignored the others. In another study, it was clearly stated by the authors that they were not studying climate and that their results could not be taken to reflect the climate in the region. But that didn't stop CO2science. In another case, the study only went back 500 years from the present (to 1500). That didn't stop them from including it in the MWP. In many cases, there were very wide error bars on the temperature and/or period range, or both, but these were always interpreted kindly in favor of the preferred conclusion. In other cases, the papers or graphics were so vague as to be worthless... they looked like they were scribbled on napkins. They either came from non-peer-reviewed articles and write ups (not studies), or else the subject of the study was not actual temperatures in the period in question, so any graphs included were worthless in that respect. After too much time wasted, it became quite obvious to me that there was neither rigor nor honesty in the effort. If there were, it would be published as a comprehensive, meaningful study, such as Mann et al (2009) (which reached the opposite conclusion, by combining all available proxies and systematically determining that while there was regional warming, such warming was not global... but it did so out in the open, in a peer reviewed study, not on a web site with no rigor or honesty). It says a lot, I think, when something is designed as a fun to use interactive map on a web site, yet can't make into the realm of peer reviewed science.
  42. It's cosmic rays
    @35 (and others) I finally found the paper: http://moef.nic.in/downloads/public-information/Discussion-paper-INCCA-1-2.pdf It includes a reaction by prof Rawanathan (Scripps San Diego)
  43. Medieval Warm Period was warmer
    Re: @stefaan I don't know whether co2science had been selecting which bits of research to choose to include in their database or not but I know at least one instance where they misrepresented the results of the research. I'd felt for a while in their blog that they had been misrepresenting the results of published research, but I had no evidence so finally after I was pointed to another entry on the co2science website I decided to follow up and I read the original papers and contacted the lead author, I then wrote the results up on my own blog. You can read that here: http://oxfordkevin.carbonclimate.org/?p=469 Basically the lead author stated that "Our figure does not lead one to conclude that past sea surface temperatures were warmer than today as is suggested on these websites" My personal conclusion from this experience is that I cannot trust the work that they have done. Kevin
  44. actually thoughtful at 05:54 AM on 24 January 2011
    Monckton Myth #4: Climate Sensitivity
    @Dikran: "(a good way of telling if a paper is any good is to look at its citations, if nobody cites it, it is generally because it is either uninteresting or incorrect). This advice is beginning to break down, as, due to the intense pressure to let the deniers have published papers (like letting your kid brother play ball even though he isn't coordinated enough but MOM said you had to let him play). Now we have these sub-par papers (McShane, Lindzen (according to commentary here), a recent paper that purports to show Antarctic warming at 1/2 of previous levels, etc.) and future denier papers will heavily cite these papers in order to run them up the credibility scale. It is the inevitable result of playing the "no peer reviewed papers" trump card. What is missing, quiet simply, is thet desire for honest results. The deniers are an entire industry that wants the answer to be "no warming; if warming, natural causes only" - and they will do anything to accomplish this, including perverting peer review. In fact they have already begun. In two years time deniers will be touting their "body of evidence" in peer reviewed journals. In 5 years time it will be true. Note - I use the term denier here quite intentionally. There are many skeptics who provide honest analysis of what we know we don't know (or think we know but don't). Trenberth being the Platonic ideal of a skeptic with his "travesty" comment. Even Pielke Sr. is using scientific method and the proven peer review process to establish (or see destroyed) his claims regarding ocean heat.
  45. It's cosmic rays
    pdt, I wouldn't get your information from sources like THE REGISTER. Having done a search for this 'paper', I have only found links to the usual sources of denial (like the one you found), most of them having copied a report from THE HINDU. In that original report, it states that Dr. Rao's findings were released "as a discussion paper" by the Indian Environment Minister. Another Indian source calls it a "scientific review...[of] recent studies..." There is also a report in the HINDUSTAN TIMES, with a reaction from V Ramanathan of the SCRIPPS Institute. None of the reports I found, actually had a link to the paper or, even, any information about the title or where it was to be published. Seems like they were just interested in copying and pasting something that sounded to them like an anti-AGW paper. Strange, eh ? Doesn't appear to be that hoped-for 'final nail in the coffin of AGW' that some are hoping for (yet again).
  46. Monckton Myth #4: Climate Sensitivity
    RW1 - I've read the Lindzen and Choi 2010 paper as well. While submitted to JGR, it hasn't been published, hasn't made it through peer review yet, and I don't know if it will. They are still using a simple geometric extension of their tropical data to the rest of the globe (they refer to the well debunked method of L&C 2001), whereas Trenberth 2009 notes ENSO variations move an order of magnitude more energy between tropic and subtropic regions than their calculated imbalances. And Murphy and others have shown that using global data sets even with L&C's methods show much higher climate sensitivities. Having read each version of their paper, I don't believe they have addressed even a fraction of the serious issues pointed out to them.
  47. Oceans are cooling
    #50: "Can you direct me to a source" You could call your local HS physics teacher or look here. Low thermal conductivity translates to high thermal inertia, as 'inertia' is commonly understood to mean resistance to a change of state. I see the results of a very similar experiment every day in the summer because I live in a brick house in a hot climate. But this is not about bricks or shuttle tiles. It's about the response of the oceans, so please respond, in the context of KR's comment #46, to the discussion of the thermal inertia of the oceans presented in the linked NOAA paper in #49.
  48. Hurricanes aren't linked to global warming
    Does anybody have a comment on this paper cited by post 20? (the Maue paper). Its a new 'hot item' among gw denialist sites...
  49. It's cosmic rays
    #33: "a recently published paper" Thanks for finding the appropriate thread. It appears that this is one from the 'here-we-go-again' department (I note that W^W# has already picked it up). I won't bother with snide editorialisms in the Register article or any of the other newspaper feeds that parrot it. Here is a link to the Rao paper (it's actually a 'research communication') to be published in the IAS publication 'Current Science'. I see several points in a quick look: a. No new data are presented b. The most recent reference is 2007 c. He relies on the 'well-established excellent correlation' between GCRs and low-level clouds. The CERN CLOUD experiment, designed specifically to test this, has yet to produce any such results d. He pulls a graph from a 2005 paper (Veizer) to show 'correlation' between surface neutron monitors and 'low-level cloud intensity'. Although this is supposed to be a heat-trapping mechanism and the conclusion of the 'paper' is that this is a significant part of global warming, he curiously omits any temperature data. e. He makes the usual hash of GCRs-> more high level clouds -> cooling due to increased albedo and GCRs->low level clouds -> warming due to heat trapping. Same old song, not even a new verse.
  50. It's cosmic rays
    This recent "The Register" article about a recently published paper on the influence of cosmic rays on climate presents a very different picture than the one shown here. I would be interested in seeing a assessment of the paper if anyone has time.

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