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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 128001 to 128050:

  1. Models are unreliable
    Some notes on modellers and modelling: I have worked in computer modelling within science and government, and have had some run-ins with those within science who attempt to reduce complex modelling down to one variable-their field of research. I have seen hundreds of millions of dollars of development projects almost shelved because these projects were not supposed to have even been occuring, under one scientists or faction of scientists (generally those who have spent their entire careers within the public service, outside the real world), particular, individual model or dataset. Some of these 'only my field/dataset' modellers don't even bother to check all relevent data, and moreover they want policy decisions to be based on simple models, by default, as away of bringing 'order' to the world. Their 'order'. This sort of process, is the very reason we don't allow governments to control societies; there are always those within government, including within science, who want to impose their partcular 'science models' on the world, when in fact it is really about imposing their political philosophy (commonly socialist), and self-interest. There are other patterns that tend to occur in these sort of modellers, and their cohorts that I have noticed: -They don't like chaotic systems -They don't like inbuilt uncertainty -They don't like changes in uncertainty -They don't think that the common 10% or so of data that doesnt fit into a dominent model, is relevant, or at best think that it can only account for 10% of effect. -They tend to think all natural systems are smoothly curved. -They tend to think that fields of research outside the 'dominant' have little relevance. -They have a common disrespect for market forces in society. -They think that their field is superior to other fields. -They don't like being unable to dominate or control human politics -they get to the point that they believe that the issues are settled, and that debating issues and prolonging the political process is a waste of time and taxpayers money, examining any new data is also a waste of time, and inefficient, since the debate was settled long ago-by their dataset. They are geniunely astonished when one points out real-world instances which have significant effects (eg >10%), which do not fit into their 'dominant' model. They would have bet their house that these wouldn't occur. The above assumptions are not based on actual data, but on social and political assumptions that those who hold them tend not to be aware they even have, or that they are even questionable; and are inconsistent at best when applied to the real world, or at worst, simply wrong. A good example is the 'nature is generally smoothly curved' assumption. It is surprising how common this is in 'modellers' (eg financial and in climate), and how uncommon it is in nature, and moreovoer what effect the common ~10% of data that doesnt 'fit' can have. Some of the best examples I can think of are the element iron in the periodic table (which causes stars to go supernova-there is nothing 'smooth' in this process-and the periodic table in general for that matter), and the process of natual selection itself-where a minority variant can replace an entire pre-exisitng variety/species. (In both these cases, according to the assumptions innate in many modellers, we wouldn't even be here! since eg our solar system formed from a supernova, and of course from evolution, which are both, not 'smoothly curved' processes. (So much for the ~10% of a dataset having 'low effect'). Note also, if you want historical examples of where intellectualism and modelling/ideology can go drastically wrong: - Richard Pipes of Harvard blames radical academics for providing the foundation, framework and justfication for radical Bolshevic communism in the late 19th century-early 20th century. -Weikart blames German Social Darwinists and intellectuals in the late 19th-early 20th century for providing the foundation, framework and justification for radical Nazism -Social Darwinists/Eugenics movement came from within radical academics and intellectuals, who also attempted to impose their 'science model' on the world in the early 20th century (with Nazism as an offshoot of this). -The financial crisis of 2000s, where the 'expert banks' and their modellers got it all wrong. -Human-induced global warming modellers, (>90% sure that there is >90% effect from human activity). The jury is still out on the last one, but their general manner and methods, in my opinion, are not all that dissimilar to the previous ones.
  2. It hasn't warmed since 1998
    @Den siste mohikanen who is scaring children, or keeping anyone in poverty? first of all, the only thing we should be able to agree on, is that virtually nothing has been done so far to actually slow down climate change. for every Prius added to the road (which still runs entirely on fossil fuel), there's another new SUV. we've been talking about this issue, but doing virtually nothing. where are the scared children? the younger generation is growing up with the same over-consumption habits as the older generations. and who is "kept in poverty" by climate change science? an analysis of the recent proposed climate bill (going through the US house of reps) is that it would cost the average US family (not person) $175/yr by 2020. how does that amount keep anyone in poverty? who is going to be "kept in poverty" if we do nothing are the poorest countries in the world, that already struggle to find enough water, and grow enough food, to meet demand. it's those countries that will be hardest hit by higher temperatures, not the cooler, wealthier northern powers. they'll be kept in poverty by those who refuse to act on climate change. not the other way around. please don't twist the argument to make it seem like the skeptics are the ones standing up for the poor.
  3. Antarctica is gaining ice
    PaulM, Chill, amigo (no pun intended). The article makes the distinction right off the bat between land ice and sea ice. Your two links discuss SEA ICE. We know there's been an increase in sea ice. In a place where the temperature is always well below freezing, "global warming" is not going to melt all the ice. That doesn't mean it isn't a problem elsewhere. Even if there were no net ice loss on earth, if we're losing ice in places we need it (such as mountain ranges that supply people with drinking water), and accumulate it in places that have no humans at all (Antarctica), that's an enormous problem. The persistence of climate change skeptics in using Antarctica to say "look, everything's ok", is really beyond absurd.
  4. Philippe Chantreau at 06:21 AM on 28 June 2009
    The CO2/Temperature correlation over the 20th Century
    Ideology and name calling as well. Inbred? Ordinary scientists, as opposed to what, extraordinary? Whatever. Methinks the aforementioned relationship has been investigated rather well and is actively investigated as we speak. Since you have a "model" and you're a scientist, by all means you should publish. You'll be an instant hero to everyone sharing in your ideology. Considering that even garbage as pathetic as Gernisch and Tscheuchnauer can make it in respectable publications, for the sake of presenting "the other side", your high quality work should be a breeze to get out there. And there is always Energy and Environment.
  5. David Horton at 22:09 PM on 27 June 2009
    The CO2/Temperature correlation over the 20th Century
    #40 "vested interests of bureaucratic, anti-capitalist science" - and so we get down to the ideology. Always do, in the end.
  6. This just in - the sun affects climate
    "Link between the earth's magnetic field and low-latitude precipitation? Mads faurschou knudsen and Peter Riisager, Department of Earth Sciences, University of Oxford, Parks Road, Oxford OX1 3PR, UK. Pages 71-74. Based on an observed correlation between the Earth's magnetic dipole moment and oxygen isotope paleo-precipitation records from caves in Oman and southern China, knudsen and Riisager suggest that the Earth's magnetic field may have influenced the amount of rainfall in low-latitude regions during the past 5000 years. The physical mechanism that underpins the geomagnetic-climate link is provided by the cosmic-ray-climate theory, which suggests that galactic cosmic ray (GCR) particles entering the atmosphere influence the formation of low-altitude clouds and, in turn, climate. The geomagnetic field shields the Earth from GCR particles and, according to the cosmic-ray-climate theory, it therefore has the potential to influence cloud formation, rainfall, and climate. Since the amount of GCR particles entering the atmosphere is also modulated by the Sun, the cosmic-ray-climate theory is central to the ongoing scientific debate regarding the role of the Sun in climate change. knudsen and Riisager lend support to the notion that variations in the Earth's magnetic field may influence the climate of our planet. They also deliver independent support for certain aspects of the cosmic-ray-climate theory." http://www.bio-medicine.org/biology-news-1/January-GEOLOGY-media-highlights-6592-9/ There are other sites giving an over-view of this research. In addition there is the ongoing debate over magnetic field/cosmic rays/cloud initiation as posted in "Do cosmic rays cause clouds?" thread.....see http://www.space.dtu.dk/English/Research/...
  7. The CO2/Temperature correlation over the 20th Century
    Thingadonta: your analogy does not reflect the real world. Better to imagine a lamp shining on the SURFACE of a bowl of water. The bottom layers of the water will stay (relatively) cool due to stratification so absorbed heat is restricted to the uppermost layer. This what happens in the ocean. Whilst there will be a thermal inertia effect it will be much shorter than you suggest.
  8. The CO2/Temperature correlation over the 20th Century
    : 39. A strange post indeed. Some comments. Methinks that solar variables, especially over the long term, have not been investigated enough to be dismissed as having only a minor effect on recent earth climate change. Note, once more, as I have said many times, THE HOT PLATE (IN THIS CASE THE SUN) IS NOT TURNED OFF, NOR IS IT REMOVED, RATHER, A SUSTAINED PEAK OF SOLAR ACTIVITY IS MAINTAINED (SINCE ~1950-2000s), WHICH CAUSES THE T of the earth to continue rising, as it has not yet reached equilipbrium. A heat lag effect occurs, following the rise from solar activity from about 1750-1950, which, by analogy, also occurs eveyday for daily T, with about a 20-25% time lag from the noon peak to between 2-3pm. Correlating this 20-25% time lag to the rise in solar activity from 1750-1950, gives a time lag of ~40-60 years, gives a peak in the early 2000s, which is also what is observed. It is a model that has not been properly investigated in various time lag analyses of solar activity from 1750-1950 (eg Usoskin 2005, Haigh 2003), which look at short term peaks and troughs, not total warming end-point trends. The question of flattened T 1950-1970 may be explained by ocean absorption, or even the 'aerosols' of the global alarmists. If this is wishful thinking, then it is also wishful thinking on the part of the human-induced global warmists, who invoke exactly the same mechanisms. I also note that the current global warmists also invoke a 'wishful thinking' mechanism to explain why the earth is not heating in the last decade, using eg oceans absorbing heat. So its ok when they do it, but is wishful thinking when someone else does it? My model of long term heat lag effects actually predicts a flattening in T in the last decade, as heat lags effects of 20-25% of total warming time from 1750-1950 subside, global warmists have to actually invoke your 'wishful thinking' to expalain why the earht is not heating in the last decade. Is there a double standard in your thinking? Who is doing the wishful thinking? As for what makes me think the earth is reacting to changes in the sun, have a look at what happens every day the sun comes up? Is this so unreasonable, to look closely at earth-sun relationships? Methinks, the overthrow of c02 as a dominant mechanism driving climate change will ultimately come from ordinary people and ordinary scientists, who can see with their own eyes how the sun is dominant over all other forcings, but it won't come easily from the inbred, vested interests of bureaucratic, anti-capitalist science.
  9. David Horton at 15:25 PM on 27 June 2009
    The CO2/Temperature correlation over the 20th Century
    The strange thing about the thingadonta contributions is that there is no indication of why she/he thinks that the sun warms up the ocean and then that heat is released a long time later. Hence the odd debate about turning off a hot plate and a pot continuing to boil (well, yes, it does, but its temperature begins to drop immediately). I don't mean why does thingadonta WANT there to be some mechanism for absorbing energy from the sun that doesn't show up until much later, the answer is obvious. He/she believes the sun is causing global warming, and since it isn't, now, there must be, must be, a mechanism for a time lag. Because the unthinkable alternative is what the science says - the cause of rising temperature is increasing CO2. Quite why this is unthinkable is what makes all of us in the reality-based universe throw up our hands in despair. But I repeat, what on Earth makes thingadonta think that there is a mechanism in practice as distinct from wish fulfillment? What measurements, what observations, make him/her think the Earth is actually behaving like this?
  10. Human CO2 is a tiny % of CO2 emissions
    Gincko....I think you misread the post....."if CO2 is RELEASED from ocean water, the acidity DECREASES.." that's what I said and that's what you said.. so the general ph declines, and biota do better and lock up CO2 as carbonate further diminishing dissolved CO2. Since the oceanic CO2 release is due to T rising, less atmospheric CO2 is absorbed so keeping ph down.. balanced by a diminution in solution which causes more atmospheric CO2 to dissolve.....and round it goes until T drops.
  11. The correlation between CO2 and temperature
    HS,there was nothing uncivil in what Chris said. He was merely pointing out what you do. The same can't be said about your response. In the future, if you're so thin skinned that you can't handle legitimate criticism, maybe you shouldn't comment at all.
  12. The CO2/Temperature correlation over the 20th Century
    hmm i had a look but didn't notice any contribution from yourself. ;)
  13. The CO2/Temperature correlation over the 20th Century
    #36: yes, Chris and I had quite a civilised discussion in that thread concerning the role of WV.
  14. The CO2/Temperature correlation over the 20th Century
    mizi, have you read: http://www.skepticalscience.com/water-vapor-greenhouse-gas.htm
  15. The CO2/Temperature correlation over the 20th Century
    "However, for the last 35 years, the dominant forcing has been CO2." I have to disagree..the dominant forcing agent is water in its various phases, particularly as vapour. Unfortunately measuring WV variation globally to include within models is next to impossible and so estimates are used. We do know that our use of water, both industrial and agricultural, has increased enormously over the same period that 'global warming' has occurred with consequent increase in atmospheric wv.
  16. Human CO2 is a tiny % of CO2 emissions
    The "World GHG Emission Chart" is great, but I have to wonder: where does air-conditioning of cars, homes and commercial buildings fit in? If it was meant to be under "Other combustion", it sounds too small.
  17. The CO2/Temperature correlation over the 20th Century
    Thingy, I would have thought the next ten years would be enough to show whether you are right or not? The argument about the apparent flattening out, or even falling over the last ten years is that it is not a long enough period to read any trend into it. But surely the last ten plus the next ten is? But I hope you are right. I have a 1 year old daughter who could therefore live to see 2100. Scary.
  18. The CO2/Temperature correlation over the 20th Century
    re: 31, and re:13: One possible reason that earth T flattened following the solar max in the mid 20th century is one often used by global warmists-the ocean intially absorbed the heat for around 20 years from 1950-70, then the lag kicked in from 1980-2000s. A predition of this model would be that T in the norhtern hemisphere between 1980-2000s should have gone up more than the southern hemisphere, since there is more ocean in the southern hemisphere to absorb the suns warmth. This IS in fact what is observed, T has only increased slightly in the southern hemisphere since around 1980. Moreover, if one looks at satellite trophosphere T, rather than surface T, (which is suspect), T hasnt gone up that much since 1980 in any case. Another prediction from this model is a flattening of T since ~2000, especially in the northern hemisphere, as the lag effect wanes. Predictions based on this model: The sun has now waned slightly. -T in the southern hemisphere might to continue to rise slightly over the next 20 years, as the large area of ocean which has absorbed the solar max since ~1950 continues to slightly warm the atmosphere, -however T in the northern hemipshere should flatten or slightly decline (with less ocean heat which has pobalby already reached equilibrium). -Overall the earth as a whole should not warm much over the next 20 years (well below IPCC forecasts), based on a dominant solar model driving climate change. I'll check back in in 20 years.
  19. The CO2/Temperature correlation over the 20th Century
    if anyone is interested in another pot analogy, please see realclimate: http://www.realclimate.org/index.php/archives/2009/06/a-warning-from-copenhagen/langswitch_lang/sp#more-690 this one i think concerns a different kettle of fish.
  20. The CO2/Temperature correlation over the 20th Century
    Planes were grounded so there were no contrails so temperatures immediately went up, and came back down as soon as planes started flying. but isn't that a local effect? like northerly winds? i thought thingies point was that there had been hundreds of years (or whatever it was) of gradual increased solar output before ending last century, and therefore lag effects are relevant. Although (i might be wrong) i'm not sure thingy has explained what kind of earth science processes would create a lag that would flatten first and then rocket upwards later (and if he has a theory whether this can be tested with measurements)?
  21. Ian Forrester at 00:35 AM on 25 June 2009
    The CO2/Temperature correlation over the 20th Century
    There is no lag time from the sun. Just check what happens immediately after volcanic eruptions. The earth cools immediately. Check what happened in the middle East when the oil fires were started. The area down wind cooled immediately. Check what happened to US temperatures after 9/11, can you tell me what happened? I doubt it.
  22. Philippe Chantreau at 23:44 PM on 24 June 2009
    The CO2/Temperature correlation over the 20th Century
    It's easy to understand until you come up with a bad analogy. Of course the heat source is not removed, that's why your initial analogy was poor. I understand everything you say, it's really not complicated. It's just not very convincing. Your condescending tone does not make it more so.
  23. The CO2/Temperature correlation over the 20th Century
    RE 20: Shawnhet, thanks for that. re 28: Niten77, I think you've got the general idea. I dont know why a heat lag is so difficult to understand, its really quite simple, average daytime T peaks around 2-3pm, but the suns incoming energy peaks around noon (a 20-30% heat lag of the total time of warming since dawn). There is a LAG effect; there is no 'immediate' response to the reduction in solar input from noon; crudely applying this 20-30% general lag to the sun's overall warming trend from the 17th century to the mid 20th century, means you can get a peak around the early 2000s. This model doesnt necessarily explain everything (eg why was T flat from 1950-70?), and may be invalid in terms of length/degree/solar forcing etc, but the concept of a heat lag itself, following a peak, IS entirely invalid, and more so if the peak is sustained over several decades, which implies an even longer heat lag effect (eg from ?warming the oceans over several decades?). Too simple for some to understand.
  24. The CO2/Temperature correlation over the 20th Century
    Sorry for the double post. While I have no idea if such a mechanism exists with regard to the sun and the ocean, or that there would be any way to measure this in the presence of all the other forcings, it does seem like a fair comment that any significant 'lag' would result from the total energy (integral over time) of the sun's output rather that a directly proportional response. This is something I found quite confusing in Usoskin 2005 and that time lag graph.
  25. The CO2/Temperature correlation over the 20th Century
    I think there is a bit of confusion with what Thinga is trying to say. Continuing the pot on the stove analogy, lets assume: The pot has been on the stove at a setting of 5 and achieved equilibrium temp of 80C and setting 6 would give 85C, setting 7 90C, etc. I believe what Thinga is trying to get across (going back to post #11, correct me if I am wrong, Thinga) is that if you change the setting to 7 for one minute and the temp goes up to 83C, at this point even if you turn it down to 6 the temp will continue to rise. In this analogy the papers described above would be the equilivant of measuring the AC current flowing through the element and trying to correlate it to the changes in temperature of the water in the pot (though frequency and the equilibrium time are much further apart that that of the sun and Thinga's 40 year mark) As this is my first post, I would like to take the opportunity to commend John (and the majority of those whho post here) on an excellent site.
  26. The CO2/Temperature correlation over the 20th Century
    re: 22, 23, 24. The heat source is not removed. A heat lag on earth follows a peak of solar activity- Usoskin 2005 agrees, and concludes this heat lag averages ~10 years over the last thousand years or so, in an analysis of peaks and troughs of T relating to solar activity. A sustained peak since the mid 20th century implies a longer time lag, although one issue is why the earths T flattened from the 1950s-1970s. But the concept of a heat lag is really not that difficult. Annual T peaks every year about 6 weeks after the summer solstice (in Feb in the southern hemisphere), and day temperatures peak about 2-3 hours after the highest point of the sun overhead (about 3pm). In both cases, the heat is not 'removed', there is simply a lag effect, note that overall heat supplied does not increase, new heat is not 'created', but actually decreases in both cases, yet the earth continues to warm. Tough one eh! So, back to cooking classes.
  27. Philippe Chantreau at 16:10 PM on 24 June 2009
    The CO2/Temperature correlation over the 20th Century
    Thinga, don't talk down people with "as if you could turn off the Sun." You're the one who chose the analogy and the terms going with it.
  28. HealthySkeptic at 15:48 PM on 24 June 2009
    The correlation between CO2 and temperature
    Re #20 chris said;- "Unsupported assertions on dodgy web sites are rarely helpful HS and you've again dumped several on this thread." I think you need glasses, chris (and perhaps a valium as well). So far I have provided only ONE link to a website in this thread. (One that John Cross graciously thanked me for.) I would prefer answers to the questions I posted rather than the condescending platitudes and the mass of references to vaguely relevant papers and articles that you dish out time and time again. In future, if you can't respond to me civily, please don't respond at all. HS.
  29. Philippe Chantreau at 14:48 PM on 24 June 2009
    The CO2/Temperature correlation over the 20th Century
    Ian is right. The total energy of the system CAN NOT increase after the heat source is removed. If the heat source is removed and the energy proxy (i.e.water temperature) shows an increase, it means that an element of the system acted as a heat storage and is now releasing that heat faster than the decrease due to removing the source AND in a way that can be reflected by the proxy. So the kettle analogy is rather poor. Shawnhet's description is probably better. Furthermore, if Thinga wants to make the argument that there is an unknown storage element that releases heat exactly at 40 years, the necessity for a physical mechanism becomes imperious, lest the heat storage idea become nothing but a fudge factor. As a layman, I am unconvinced because it does not seem to add up. TSI variation are very small. If the climate can react that wildly to such small forcings, then we might be in for some serious sweating with just the CO2 released so far, even witout all the feedbacks.
  30. Ian Forrester at 11:33 AM on 24 June 2009
    The CO2/Temperature correlation over the 20th Century
    You asked for a scientist to respond to your crazy pot boiling. Well I am a scientist, BSc in chemistry and PhD in Biochemistry and your pot boiling is a load of nonsense. If you knew anything about thermodynamics you should know that energy is neither created nor destroyed. The energy in the pot cannot increase after you remove the source of heat. Thus its temperature cannot increase after removing the source of heat. It is that simple. Go and read some texts on thermodynamics. I am glad that you seem to be only a "blog scientist" and your ideas are confined to the blogsphere and not the real world.
  31. The CO2/Temperature correlation over the 20th Century
    re: 19 This sort of argument of your shows how people don't understand much about thermodynamics. Will chemists and physicists please contribue to the debate on global warming, so self-ordained stove specialists dont end up running run the worlds economy? If this sort of argument is any guide, I dont have any faith in the ability of global warmists to properly assess the affect of the sun on rising earth temperature, with lag effects. The question is one of lag effects following a sustained peak of T (not turning off an element, as if one could turn off the sun). The rather simple point is, T will continue to rise after heat has reached a sustained peak, roughly equivelent to the total area under the curve of the T graph, from the start of heating. It's really very simple, the same as a days highest T occurs about 2-3 hours after the sun has reached a peak overhead. PS: I am a scientist. I hope you don't intend to cook anything with your pot-understanding.
  32. The CO2/Temperature correlation over the 20th Century
    I think what thingadonta is saying (to paraphrase) is that a persistent increase in solar energy in the last couple of centuries would increase the equilibrium temperature of the Earth. However, before the temperature will reach that equilibrium, the oceans will first have to warm. As the oceans slowly warm, they will continue to pull up the temperature of the Earth, even though the solar energy may have plateaued already. As analogy, if my burner is set to a temperature of 90 deg C and the water in the pot is 25 deg. C, the temperature of the burner does not have to keep increasing in order for the temperature of the water to keep increasing. There is no inherent contradiction btw saying the sun's energy has remained constant over the last X years and saying that the sun's energy has caused the Earth's temperature to continue rising throughout(for example) that period. Cheers, :)
  33. Ian Forrester at 01:21 AM on 24 June 2009
    The CO2/Temperature correlation over the 20th Century
    Thingadonta, your analogy is false for the following reason. The heating element is much hotter than either the pot or the water (check it, it glows red!). When you turn off the the power the element has to cool to a lower temperature than the pot and water before cooling of the water starts. There is a lot of heat energy in the red hot element that has to be dissipated before cooling of the water starts. If you remove the pot from the element rather than turning off the poweer cooling will start immediately (the pot may be a little warmer than the water) but total heat energy will start dropping right away. Non scientists should think through their analogies carefully before drawing wrong conclusions.
  34. CO2 lags temperature
    MattJ: It has been demonstrated empirically that plants do indeed flourish if CO2 levels are higher than the present 380ppm or so, all other things being equal. Many horticultural industries use CO2 augmentation to grow bigger plants, faster. (Levels of around 1000ppm which is still low enough not to have a deleterous effect on animal health). Coupled with the knowledge that in the deep past the plants we now burn as coal grew in a climate with far higher CO2 levels ( and were adapted to such) and by locking up that CO2 reduced levels to around 200ppm...at which point they had 'starved' themselves..some species to extinction. About 8Mya, the grasses appeared - well adapted to thriving with low CO2 levels ( and are arguably the most successful plants we know). So there is no valid counter-argument. Climate is a highly complex interactive system and responds to changes in the physics and chemistry of the sun and this planet ( including those produced by life itself) and so it is necessary to look at ALL factors and how they interact, not focuss on a single mechanism. In that regard this site actually does quite a good job.
  35. This just in - the sun affects climate
    The earths magnetic field has been declining for several hundred years, and some are worried that it might actually flip soon (we will see compass's needles pointing south, instead of north-this is common in geological time, and has been used to correlate, in time, magnetic-bearing rock sequences which show identical flip patterns over time. I think, from memory, magnetic flips occur roughly every several hundred thousand years, (but don't quote me on this) and,to use a bad cliche, "we are due"). Anyway, I read in some internet sites that a lower magnetic field suggests an increased solar effect, it is mentioned in eg the meeting between Minister Wong and Fielding and Co. scientists, but I dont have any papers per say, on hand. Try the NIPCC 'climate reconsidered' report which is a good overview of alternative theories, also Plimers recent book may contain reference footnotes on it.
  36. The CO2/Temperature correlation over the 20th Century
    re:17 "Of course, if the water in the pot actually went on getting warmer for the next 40 years it WOULD be perplexing". This is a ridiculous and dishonest statement. The pot is an analogy, the time period of heating of the pot (minutes), has nothing to do with the time period of heating of the earth from the sun (years); the parallel is in the principle of a heat lag afer a sustained peak. You must be an incrediby dishonest researcher to falsely equate the RAW time periods of the two, yet not recognise the parallel in concept. The point is, is that time lag of heating anything relates to the area under the curve of total warming, not short term peaks/troughs. This indicates that a SUSTAINED solar peak from the mid 20th century, starting from a rise in the 17-18th century, can account for warming in the latter 20th century.
  37. The CO2/Temperature correlation over the 20th Century
    Thingadonta: "If one increases temperature to a pot on a stove, and then flattens or decreases the temperature, the potwill show a small lag time effect, then will CONTINUE to heat for a period afterwards, and then slowly decline." If what you're saying - and it's not that clear - is that the water in a pot will continue to warm for a bit after you turn off the hob then sure. If you were trying to determine if the hob was still on by only measuring the water temperature then you would obviously have to wait a bit before the actual status of the hob became clear. OTOH, if you were monitoring the hob directly you would know as soon as it was switched off. And note here that we are monitoring the sun's output directly with satellites. Now, from what you say, you strike me as the kind of guy who'd switch off his stove but not believe it until he'd checked the water temperature was actually on the decline. It's good to check. Of course, if the water in the pot actually went on getting warmer for the next 40 years it WOULD be perplexing. It might be that you'd actually turned off the wrong hob. Or, of course, it could be the sun.
  38. The CO2/Temperature correlation over the 20th Century
    chris, thanks for taking the time to respond. much appreciated. cbj
  39. The CO2/Temperature correlation over the 20th Century
    Thingadonta: just because you can imagine a thing doesn't make it true; nor does it make it the most likely. The trick is converting what seems fanciful to most people (I imagine) into something convincing. PS. Your coffee was superheated, meaning that the temperature continued to rise above the boiling point. It's not as though the energy disappeared and then re-appeared.
  40. The CO2/Temperature correlation over the 20th Century
    re:13 1) My reference to Haigh 2003 was that she implies the potential for solar forcings after a sustained period......"chemical and dynamical processes in the middle atmosphere may act to amplify the solar impact". 'Amplify' means that a time-lag component is implied, you cant 'amplify' something without a time lag, but I did think she addressed longer lags by the flavour of her paper. I don't have the rest of her paper now, but very few of the others i have perused on tnis site even bother recognising that a time differential/lag is even possible after sustained solar activity, or that 'dynamical processes' can 'act to amplify solar impact'-this stark lack of address of such a simple concept as time lag after a sustained peak activity, should give pause for thought. It is entirely reasonable, thermodynamically. 2) "So what can have caused the long lag before any warming occurred in response to the maximum in solar output in the 1950’s?" Note that earth T went flat at roughly the same time as ths sun did (1950s). So far so good. Now sustained solar activity bombards the earth for 20 years. It is entirely reasonable thermodynamically, for a complex system to parallel and absorb this sustained flat activity until a saturation point is reached, before T starts rising again (although there would hve to be some kind of buffering/inhibitor, similar to H bonds in water with boiling-I dont know what this is, only that it is theoretically reasonable); another possibility is a slow reduction in clouds in response to lower influx of cosmic rays and sustained solar wind. Another possibility is UV changes. The possibilities are numerous, but the main point is, that the concept of delayed effects following a sustained peak of activity is NOT unusual in thermodynamics. (EG I once opened the microwave after heating a mug of coffee too long, with no observable effect on the long-bombarded mug of coffee-no boiling was visible, but with the slightest disturbance to the surface of the water-the water literally exploded out of the cup-the heat energy was absorbed by the water for some time without any boiling, a critical threshhold was reached, and a strong time-delayed effect followed. This is relatively common in themodynamics). Overall cloud reduction by an increase in cosmic rays, if such indeed occurs, does not have to happen 'immediately'; the relationship betweeen cosmic rays and cloud cover etc may build up over ~20 years of sustained solar activity 1950-1970, before a critically low level of cloud formation mechanisms are reached, with subsequent rising temperatures. ??? I dont think aerosols have much/anything to do with T in the 20th century, primarily because aerosols have NOT declined since 1980, if anything the high rate of industrialisation in unregulated 3rd world industries in the latter 20 century suggests that aerosols have increased. Also, aerosol reductions are just a cop-out/ego trophy for greenies. As for predictions, i guess T shouldn't rise over the next 20 years (?), as the sun and T have now flattened (the flattening T supports the long-lag effect of the sun, whiuch has also flattened). It is difficult to imagine a double-delay T lag, or a climbing ladder- lag T effect in the earth system (even though these ALSO exist in thermodynamics, beleive it or not). 3) As for low c02forcings, the NIPCC report contains plenty of references to peer-reviewed papers advocating such. I dont have time to review them now. But I'm pretty sure they are there, I know for a fact there are plenty which advocate significantly enhanced solar forcings. I enjoy your responses, but I still think the sun is the driving force in climate change. Check again in 2030, T shouldnt (?) have risen/much if the sun is the main force in all this.
  41. The CO2/Temperature correlation over the 20th Century
    re #11 1) O.K. thingadonta, but above you asserted that Haigh (2003) “looked at longer term time lags with respect to sustained peaks”. One only needs to read her paper to see that she does nothing of the sort. If we are going to make assertions we should back them up with reliable evidence (since this is about science and not politics or propaganda or something else!). 2) Your “thermodynamic” arguments seem suspect. I agree with you completely that the response to an enhanced forcing (e.g. enhanced and persistent solar forcing) should result in a warming response, the maximum extent of which will be delayed as the climate system comes to a new equilibrium with respect to the forcing. However there won’t be a “lag” before the warming starts (unless an opposing forcing occurs for a while; see below), and in fact the maximum rate of warming should occur early in response to a change in forcing. That applies to the climate response, just as it applies to any simple experiments with water in a pan on a cooker (why not try it?!) or the response to enhanced insolation during the day or as a result of seasonal variations. So your notions are incompatible with the record of temperature variation throughout the 20th century. The surface temperature rose somewhat in line with a small increase in solar forcing from the early 20th century to the mid 1940’s but then went pretty flat for around 30 years (see Figures in John Cook’s top article above). The solar output maxed in the 1950’s. So what can have caused the long lag before any warming occurred in response to the maximum in solar output in the 1950’s? The explanation for the temperature stasis in the mid-20th century is the effects of atmospheric aerosols which produced a negative forcing (see Figure 2 in John Cook's top article). Can that be used as an explanation for a lagged solar contribution? No not really. That would only work if the negative aerosolic forcing was suddenly reduced around the early 1970’s so that the aerosolic suppression of the effects of enhanced solar forcing disappeared. However that doesn’t work, since all the evidence indicates that the negative aerosolic forcing has increased since the 1950’s, largely due to continuing industrialisation and “dirty fuel” use in the developing world (see Figure 2 in John Cook’s top article; see also http://www-ramanathan.ucsd.edu/publications/Ram-&-Feng-ae43-37_2009.pdf ) What warming forcing has increased since the 1970’s that can have “overpowered” the cooling effects of atmospheric aerosols? Not the sun. We know categorically that its small excess forcing maxed in the 1950’s. The greenhouse gas forcing has increased markedly especially from the mid-late 1960’s (see Figure 2 in John Cook’s top article). The temperature rise has followed that increased forcing pretty much as we might expect (no lag!), even if internal variations in the climate system has overlaid the temperature rise with noise. 3) With respect to the large amount of quantitative information on the rather small effects of solar forcing to 20th century warming (a couple of examples I gave in my post #7), you suggest that you could “just as easily quote those who conclude the opposite”. Fine, then why not do so? So far you are arguing by assertion, and the one paper you cite in support of your assertions (Haigh, 2003), doesn’t actually say what you says it does. Since these are scientific issues we should be interested in the properly published evidence and not unsupported assertions.
  42. The CO2/Temperature correlation over the 20th Century
    re #9 Yes I think that's right canbanjo. The situation is complicated by the fact that the solar output goes up and down somewhat on fixed (solar cycle) and variable time scales, as can be seen by looking at the sunspot numbers as a proxy for solar outputs: http://en.wikipedia.org/wiki/Sunspot So while the climate response to a change in solar output is certainly going to be "lagged" (but note that this "lag" refers to the maximum response rather than a lag in the onset of the response!), the variability will result in a range of response times, and so as you say, the graph in Usoskin will have some relationship to "averaged" lags. Again I think you're right in suggesting that just as one can assess causality via an analysis of correlations between a number of events (e.g changes in solar output) and their responses (surface temperature changes), we can also examine individual specific examples (e.g. late 20th century warming) in mechanistic detail. An analogy might be assessing the statisical relationship between ciggie smoking and lung cancer via analysis of large populations of smokers and non-smokers. In addition to this statistical analysis, we could look at a single individual and observe, for example, carcinogen-induced DNA damage in the lung cells of a smoker to assess the mechanism that underlies the statistical correlation observed in populations. So if we do this for late 20th century warming, we find that the mechanism (warming response to change in solar output) is incompatible with the evidence and what we know of the physics of radiative forcing and the climate response, at least to the extent that I outlined in my post #7.
  43. The CO2/Temperature correlation over the 20th Century
    Chris some points: 1) The issue, as you say, is persistent/sustained solar activity, which in my opinion allows a longer time lag (eg 35 years) to be viable with regard to solar-induced earth warming. The 10 year lag recognised by Usoskin 2005, and the shorter lags recognised by Haigh 2003, are not related to sustained periods of solar activity. The sun's sustained activity in the last ~60+ years implies a longer thermodynamic time lag to the short peaks and troughs analysed by Usoskin and Haigh. This is a pretty simple calculation, relating to the total area under the curve of sustained activity.In simple terms: longer sustained peaks create longer lag effects. This is exactly the same reason that on an average day, highest T is reached well after the sun reaches a peak (ie from the total area unde the curve throughout the time from dawn to noon), whilst shorter term lags occur throughout the day from shorter-term peaks, such as from cloud cover etc etc. 2) I don't agree with your statement: "But there’s certainly no physical basis for a long lag, where nothing happens, between the forcing and the response". This sort of argument is contradicted by eg thermodynamics, eg heat effects on partly 'buffered' systems (eg an example being water boiling), and also past earth climate changes/lags. 35 years is nothing with regard to earth time-lags to heat. An important issue is thermodynamic response by the earth's climate to prolonged-sustained solar activity, rather than a short-term peak. If one eg heats water to close to 100 degree C, is doesnt boil unless significant more energy is applied. In other words 'tipping points', are a typical feature of sustained heating on multi variable complex systemssuchas the earths climate, as much as in other complex fields. We shouldn't expect a linear response, from the earth system, to sustained solar actinity, in whcih case a flat-lining for 20 years is not unusual or unexpected. It is only after heat energy is sustained for a longer period that the T, as we have observed in the latter 20th Century, will start to rise again, probably due to negative-feedbacks and oceanic heat lags. This is not unusual, either in earth history, or in thermodynamic systems. 3) the question of changes in the sun being 'enough' to warm earth ~1 degree C since 17th century is supported by similar changes in the past climate, which were due undoubtedly due to the sun, (as there were no changes in eg C02). In other words, I contend that solar forcings are vastly under-estimated, whilst c02 forcings are vastly inflated, to support various bias/agendas. You repeat the conclusions and estimates of those who attribute low solar forcings to climate change. I could also just as easily quote those who conclude the opposite-that there are only low c02 forcings. Which is correct? Earth's past climate is one guide, and it doesn't look good for those who support high forcings for C02, and low sun forcings. The only thing one can conclude from examining climate history, is that humans learn nothing from climate history. I suggest, that thermodynamic, non -linear effects are sufficient to explain heat lag effects from the sun on earth T inhte 20th century, and flat line periods (such as is occuring in the last decade).
  44. Adlai Gavins at 20:59 PM on 21 June 2009
    The CO2/Temperature correlation over the 20th Century
    John Cook, I'm not a scientist but a layman. Can you please explain to me how they derived past global temperature anomolies from the based period of 1951-1980? Thanks. P/s: excellent site. I'm glad that I've stumbled onto here. Cheers!
    Response: The NASA GISS temperature record displayed above is constructed from weather station measurements over land and ship measurements over the ocean. The 1951 to 1980 base period is arbitrary - if you change it to a different period, the trend is exactly the same, it's just the Y-axis that shifts.. More info here...
  45. The CO2/Temperature correlation over the 20th Century
    thanks chris i have since looked up correlation coefficients on wikipedia and realise it is complicated but am i right in thinking the graph gives the 'average' correlations over the period studied. But then analysing the actual period in question, we can see that particular factors (as you explain in 7.) demonstrate that the average 40 year lag correlation does not fit, so we can confidently say that in this 40 year period the correlation would be much closer to 0, rather than 0.3. does that make sense? thanks
  46. The CO2/Temperature correlation over the 20th Century
    canbanjo, those are very low correlation coefficients And if one is going to attest a 40 year time lag based on a correlation coefficient of 0.3, one may as well attest a time lag of -20 years which is also represented by a correlation coefficient of 0.3. More likely the null hypothesis applies, namely that there isn’t a significant relationship between solar variations and a 40 year-lagged (or -20 year-lagged for that matter!) earth’s surface temperature response.
  47. The CO2/Temperature correlation over the 20th Century
    Re #5 thingadonta, it’s clear to me how you infer that Haigh (2003) looks at longer time lags with respect to the earth’s surface temperature response to solar variation. The only reference to time lags in Haigh’s paper is the phase lag of 1-2 years in the response of the sea surface temperature to changes in solar cycle variations in irradiance reported by White et al (1997). Judith Lean, who has also (amongst others) studied the earth’s temperature response to solar cycle variation, finds small lags (a month) between solar irradiance variation through the solar cycle and the surface temperature response [***]. How about time lags in the earth’s temperature response to persistent changes in solar activity? If we want to consider this with respect to late 20th century warming (last 35 years), we should consider (i) what we mean by “lag” and (ii) the magnitude of potential contribution of changes in solar activity. (i) There should be very little lag in the onset of the response of the surface temperature to a change in forcing. Of course the full response that occurs when the climate system has fully re-equilibrated with the enhanced forcing will take some time to occur. And so one expects to see a lag between the change in forcing and the maximum response. But there’s certainly no physical basis for a long lag, where nothing happens, between the forcing and the response. That’s what you are asserting for the large late 20th century warming, and it doesn’t seem physically feasible. So if one examines the relationship between surface temperature and solar variation during the 20th century, the temperature followed the small increase in solar irradiance [*] (or sun spot numbers [**]) with little lag, and the solar output maxed by the 1950’s. The earth’s temperature more or less followed the increase in solar activity through this period (a small lag), but then was pretty flat until the early-mid 70’s. The question is: if the earth’s surface temperature response hasn’t yet reached equilibrium with the new (1950’s) level of solar output, how can the earth’s temperature become unresponsive to the maximum in solar output for a period of 20 years or more and then suddenly start to rise rapidly with no secular change in solar output? [*]http://www.skepticalscience.com/solar-activity-sunspots-global-warming.htm [**] http://en.wikipedia.org/wiki/Sunspot (ii) lag or no lag, have the changes in solar output been sufficiently strong to produce temperature changes of the magnitude we’ve seen? Not really. If we go back to the Haigh (2003) paper you referred to, Haigh analyses the empirical data to conclude that the solar contribution to the earth’s surface temperature change has been around 0.35 oC since the Maunder minimum (i.e. early 18th century; see [**] again). Since it’s likely that the earth’s temperature has risen by over 1 oC since then, the solar contribution to warming during this entire period is at most 35%, with essentially all of this occurring before the mid 20th century. Likewise Lean and Rind [***], determine from an analysis of monthly solar irradiances from 1889 that the solar contribution to the surface temperature has been around 0.1 oC during the entire period (and largely in the period 1900-1950). Lean and Rind conclude that changes in solar output have contributed around 10% of the warming in the period 1906-1996. So lag or no lag, the changes in solar output are simply not large enough to have made much of a contribution to 20th century warming as a whole, let alone the very marked warming of the last 35 years. [***]J. L. Lean and D. H. Rind (2008) How natural and anthropogenic influences alter global and regional surface temperatures: 1889 to 2006 Geophys. Res. Lett, 35, L18701
  48. This just in - the sun affects climate
    Thingadonta, you seem to think you have a model of climate with which you can attribute portions of temperature change to specific causes. And you think that yours is better than models used for such purposes by "all the PhDs" who contribute to climate science via research articles used by the IPCC. Rather than making an anonymous assertion that can't be scrutinized by others, please show us the model. "It is one of the biggest arguemnts of skepics [#6]" -- perhaps the model is already published? If not, then maybe you can convince a skeptic luminary to help you formalize it? That would be excellent, because then the model could be used to make predictions. I gather from what you've written that you expect temperature to decrease into the future. How much future warming will be inconsistent with your model? PS. Can you cite a peer-reviewed scientific publication describing the effect of Earth's magnetic field on average surface temperatures?
  49. The correlation between CO2 and temperature
    For Andrew K, I think you've ignored what John Cross wrote about the length of time that volcanoes have a strong effect on temperatures. But for me there is a statistical point that is more important -- you can't perform a frequentist statistical analysis every time you get a little more data. Doing so invalidates the accepted Type I error. If you flip a coin 100 times and THEN look to find out whether you have rejected the null hypothesis' expectation of 50:50, that is a valid test at some arbitrarily accepted Type I error rate (typically 5%, or 1 out of 20). If you decide to flip a coin up to 100 times and perform the same test after each flip with the intent of stopping and reporting a significant value when you reach it, you are inflating the Type I error because you are making no correction for the number of tests you are performing: "one out of 20" is no longer fair because you have increased the number of tests.
  50. The CO2/Temperature correlation over the 20th Century
    Re 4. The 40 year lag on the graph corresponds to a correlation coefficient of about 0.3, compared to about 0.55 at 10 years. (maybe 5. is a more detailed version of this query?) Appreciated if you could explain. Thanks

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