JoNova

A science presenter, writer, speaker & former TV host; author of The Skeptic's Handbook (over 200,000 copies distributed & available in 15 languages).


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The missing hotspot

The ‘Hotspot’ is crucial to the climate debate.

If greenhouses gases are warming the planet that warming will happen first in the cold blob of air 8-12 km above the tropics. It’s freezing cold up there, but it ought to be slightly less freezing cold thanks to greenhouse gases. All 20-odd climate models predict warming there first—it’s the fingerprint of greenhouse gas warming, as opposed to warming by some other cause, like solar magnetic effects, volcanic eruptions, solar irradiance, or ozone depletion etc etc.

fingerprints of global warming predicted by climate models

Look at A above, the greenhouse gas fingerprint is markedly different from the rest and dominates the overall predicted pattern in graph F. The big problem for the believers of AGW is that years of radiosonde measurements can’t find any warming, as shown in part E of Figure 5.7 in section 5.5 on page 116 of the US CCSP 2006 report

Observed temperatures - no hot spot

SOURCES:

(A) Predicted changes 1958-1999. Synthesis and Assessment Report 1.1, 2006, CCSP, Chapter 1, p 25, based on Santer et al. 2000;
(B) Hadley Radiosonde record: Synthesis and Assessment Report 1.1, 2006, CCSP,, Chapter 5, p116, recorded change/decade, Hadley Centre weather balloons 1979-1999, p. 116 , fig. 5.7E, from Thorne et al., 2005.

Is there any way the missing hot-spot doesn’t fatally kill the greenhouse theory?

Perhaps we’re looking in the wrong spot and the hot-spot is lurking somewhere else?

If we are, that gets us right back to square one. The theory of greenhouse gas warming depends on finding a hotter spot of air above the equator… if that hot spot is somewhere else, the greenhouse theory itself collapses in a heap. It means either the greenhouse effect is not causing much of the recent warming, or the greenhouse theory is just plain wrong. AGW supporters are not asking this question because they can’t win either way.

Possibly we just can’t measure the air temperatures accurately enough to find the hot-spot?

Maybe, but we’ve been recording temperatures up there repeatedly for decades, and it’s not that the hot-spot is weak—it’s absent. There is no sign at all.

AGW says: Santer and Sherwood have found the missing hot spot.

Skeptics say: Santer uses statistics to show that the hot spot might be hidden under the noise. He hasn’t found any sign of warming–just the sign of fog in the results. Sherwood ignores the thermometers altogether and uses wind gauges to tell us the temperature. (Who’d a thought?!)

On my blog there’s more answers to the claims that the hot spot is not missing here.

See all posts tagged “Missing Hot Spot”

The bottom line is that either the thermometers are wrong or the theory is.

On David Evans site there’s a full definitive explanation of the missing hot spot and all the common attempts to rebut it on one pdf here (25 pages). If you can’t open it in Mozilla try Explorer.

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164 comments to The missing hotspot

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    Michael

    There are two ways of supporting or disproving theories. The first is by experimental observation, the second is by theoretical analysis. The first has been discussed endlessly in relation to AGW on this site and others. Let me offer an attempt at the second approach.

    As a preamble however I would like to point out that the study of the absorption of radiant energy by matter is NOT climatology, it is spectroscopy. In fact most of the science behind climatology is derived from other disciplines thus it is not justifiable to take the view that only input from climatologists is relevant. In my case, I have spent the last 33 years very successfully carrying out research for a major spectroscopy company.

    Having become interested in the AGW issue I tried to derive the direct effect of CO2 from first principles. What I found was that the relationship between CO2 concentration and retained energy was logarithmic and that each doubling of CO2 would retain about an additional 3.5 watts/sq meter. Consulting the literature I find that the logarithmic relationship is widely established, I simply re-derived an already known relationship. As to the magnitude, the 4th (ie: latest) IPCC report states that the increase in CO2 concentration from 280 to 390 ppm has increased retained energy by 1.77 watts/sq meter. 280 to 390 ppm represents 0.48 doublings so the IPCC number is 1.77/0.48 or 3.7 watts/sq meter. Pretty reasonable agreement. That means the increase from 390 to 560 ppm – a further 0.52 doublings will increase retained energy by 1.9 watts/sq meter. Using Stefan’s law relating temperature with energy radiated by a black body (known and proven for more than a century) an additional 1.9 watts/sq meter will increase the temperature of earth’s surface by about 0.34 degrees C. That’s a long way from the claimed 3+ degrees C – how come? The claimed answer is positive feedback from water vapour. My immediate thought on hearing this was to note that every single naturally stable system I can think of exhibits net negative feedback so to suggest that climate (which is clearly stable) exhibits strong positive feedback makes me very suspicious, however suspicion is not evidence so lets look at the numbers.

    To get 3 degrees temperature rise requires an additional 16.5 watts/sq meter (again from Stefan’s law). If 1.9 comes from CO2, the remainder, 14.6 must come from water vapour. That would mean the positive feedback co-efficient was 14.6/16.5 or 0.88 (where 1 = runaway) WOW. Looking up the relationship between temperature and water vapour pressure in the CRC handbook I find that a 3 degree temperature increase results in approximately a 30% increase in water vapour concentration (at constant relative humidity). The logarithmic relationship applies to all greenhouse gases including water thus a 30% increase is 0.38 doublings implying that each doubling of water vapour contributes an additional 14.6/.38 watts or 38 watts/sq meter. To put this in perspective, water vapour at present only contributes 84 watts/sq meter in total. A sensitivity as large as this raises many extremely serious paradoxes and is, I believe absolutely impossible. This post is already too long for me to enumerate these but if anyone is interested I am more than willing to outline some of the paradoxes in a subsequent posting.

    The models making this prediction also predict that the impact of this water vapour feedback mechanism is a hot spot in the tropics at an altitude of about 8 km. According to the models, if the positive feedback effect of water is true then this region should be warming at least 2 times as fast as the surface. However again when I read the literature I find that 1000′s of balloon measurements and the satellite measurements all fail to find such a hot spot- and in fact this region is warming significantly less than the surface. The prediction is not supported experimentally suggesting the original hypothesis is false.

    The above only considers positive feedback from water vapour but in fact water vapour also generates very powerful negative feedback. Atmospheric water vapour gives rise to clouds and they cause cooling because they reflect incoming energy from the sun back into space. For Earth the albedo is dominated by clouds. At present it is about 0.3 which means that 30% of the incoming energy from the sun is reflected back into space (about 100 watts/sq meter- which is greater in magnitude but opposite in sign to the greenhouse impact of water vapour 84 watts/sq meter). So to consider one without the other is biased thinking.

    What is the relationship between water vapour concentration and cloud levels? I admit I don’t know for sure but I suspect it is much closer to linear than logarithmic. If there are two opposite feedback mechanisms of similar magnitude, one varying logarithmically with concentration and the other linearly, linear will dominate as the concentration rises. This again suggests feedback from water vapour is more likely to be negative than positive. If so, the direct 0.34 degree rise from an increase of CO2 to 560 ppm would be reduced not increased by the impact of water vapour.

    There is also experimental evidence easily observable by any lay person that the feedback from water vapour is negative. Again, I am happy to outline this in a follow up post if there is interest.


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  • #
    Raven

    Joann,

    I noticed desmog tries the use the nonsense that wind measurements are better thermometers than thermoteres.

    Peilke Sr. contests this claim here: http://climatesci.org/2008/06/04/comments-on-the-science-in-the-nature-paper-by-allen-and-sherwood/

    Peilke Sr. correctly points out that estimating temperature from wind speed requires that one use a climate model which means one cannot then turn around and claim that the estimated temperatures now “prove” that the climate model is correct (well I guess you can but anyone with any cognative skills should recognize that the argument is circular and meaningless).


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    Michael

    In my previous post I said I would outline evidence easily experienced by a lay person suggesting that water exerts a negative feedback effect. Here it is.

    The IPCC model is based on massive positive feedback in our climate system yet every stable natural system that I can think of exhibits strong negative feedback around the equilibrium point. Negative feedback is the opposite of positive feedback. It acts to oppose any disturbance acting on a system and seeks to maintain the current equilibrium. In short it is a stabilising factor whereas positive feedback is a destabilising factor. Long term stability of any system almost guarantees that there is strong negative or stabilising feedback in operation. The climate, while showing periodic variations, has been stable enough for life to form and flourish for millions of years despite significant changes in forcings over the millennia and this makes it virtually certain that strong negative feedback is in operation. Any analysis purporting to show otherwise should be viewed with considerable circumspection. It suggests a strong likelihood that the model is either incomplete or seriously flawed.

    We have all experienced the very significant temperature difference between a clear night and a cloudy night in winter. Clear nights are much colder than cloudy nights. Clouds act in exactly the same way as greenhouse gasses, by trapping energy radiated from the surface and returning it to the surface instead of allowing it to radiate out to space. What our senses are showing us is that greenhouse effects are not just long time constant, global issues. They are easily discerned in our local environment over timescales as short as an hour or two.

    Now consider the following scenario. We know the earth rotates about an axis tilted about 23 degrees relative to the sun, which is what gives us the seasons and what sets the tropics of Cancer and Capricorn. Imagine a location on the tropic of Capricorn (23 degrees south) – say Mackay in Queensland. In summer the sun is directly overhead – average solar input of around 310 watts/sq meter. In winter the sun is at maximum elevation 45 degrees – average solar input of around 220 watts/sq meter. That is a difference summer to winter of about 90 watts/sq meter which, if there was neither positive nor negative feedback, would give a temperature difference summer to winter of about 16 degrees (from Stefan’s law). The positive feedback suggested by the IPCC model, would act on this forcing in exactly the same way as the claimed forcing from CO2 rise and would inflate the 16 degrees to about 90 degrees C, extinguishing all life in Mackay. Yet the summer winter temperature difference in Mackay is only about 6 degrees. That is not only far less than IPCC’s 90 degrees but is far less even than the 16 degrees predicted in the absence of any feedback at all. How is that possible?

    Maybe the thermal mass of the environment averages out much of the summer winter difference? Unlikely, considering the significant temperature change between day and night. If the temperature can change significantly in a few hours it could certainly change profoundly over 6 months. Also, if the above were the reason one would also expect to see it similarly averaged out in places like Melbourne, yet anyone living there can testify first hand that such is not the case, the summer/winter variation is greater than at Mackay.

    What does stand out at Mackay relative to Melbourne is that the humidity is much higher in summer than it is in winter. Higher humidity means more water vapour content in the air. According to the IPCC model, this should translate to even more greenhouse heat retention and thus even higher temperatures. Now remember our experiences with cloudy versus clear nights, the effect should be easily discernable in our local environment over a few hours. Yet the effect is not observed, more water vapour is not leading to higher temperatures in fact just the opposite would seem to be the case. This suggests that maybe water vapour causes a net negative feedback effect rather than net positive feedback.

    Certainly increasing atmospheric water vapour does increase retained energy to a very small degree but this impact is nowhere near as strong as claimed by IPCC. It is also far from the only effect of water in our environment and some of the other effects exhibit strong negative feedback. For example, greater humidity leads to more clouds which reflect a larger fraction of the incoming solar energy back out to space and away from Earth’s surface. Or the very large amount of energy absorbed by evaporating water. Energy which is then transported upwards and eventually re-radiated high up in the atmosphere where the greenhouse effect is reduced. Or the energy taken to lift all that water several kilometres into the atmosphere against earth’s gravity (after all that is where the energy for hydroelectricity comes from). These are all negative feedback effects. (in fact the energy absorbed by evaporating water is a very significant factor in reducing the summer winter temperature difference at McKay and in the tropics generally).

    Is this consistent with a larger summer/winter temperature variation in Melbourne? Yes it is, because in Melbourne the humidity summer versus winter varies less so the negative feedback from water vapour is correspondingly smaller.


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  • #
    Michael

    A further thought that might be of interest.

    The albedo of water (eg: oceans, seas and lakes) is about 4% (only surface reflection). The albedo of vegetation covered land is also of a similar magnitude. The albedo of snow and ice is very high but snow and ice are only extensive on Earth near the poles where the insolation is extremely low which means that the energy available for reflection is a very small portion of the total solar energy reaching earth. What all that means is that most of Earth’s albedo comes about from the atmosphere – some no doubt from dust and particulates but clouds are a major factor. The albedo of Earth is 0.3 which means it is responsible for reflection of 100 watts/sq meter of energy back into space. What this means is that the negative feedback effect of water vapour through clouds is very close to the positive feedback greenhouse effect. However the positive feedback effect is logarithmic with concentration whereas the negative feedback effect is likely to be much closer to linear with concentration and therefore changing faster with changes in concentration.

    Such a situation is well known and understood in engineering systems. It gives rise to a stable operating point around the concentration where the two effects balance. Negative feedback occurs around this operating point. In our climate, water vapour concentration is very closely tied to temperature. A reduction in temperature reduces water vapour concentration which reduces the effects of clouds more than the greenhouse effect so the temperature goes up. A rise in temperature increase water vapour which increases the effects of clouds more than the greenhouse effect and the temperature goes down again.

    I strongly suspect that the fact that the positive greenhouse effects of water vapour are equal to the negative effects of clouds at the average temperature of our planet is no accident. In fact I suspect that the average temperature of Earth is controlled by this equilibrium point. That means not only that water vapour exerts a dominant negative feedback effect but that it is the controlling impact on global temperature. Factors that change the equilibrium such as cosmic rays which slightly modulate cloud formation or other greenhouse gases that add to the overall greenhouse effect will slightly shift the equilibrium but this is very much a second order (and minor) effect.


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  • #
    bugs

    I noticed desmog tries the use the nonsense that wind measurements are better thermometers than thermoteres.

    Thermometers are a problem, don’t you read Watts? It is trying to work out the height they are reading the temperatures at accurately and changing technology that are problems. Look up RAOBCORE. That is an ongoing project that has been running for years to try to get the temperatures for sondes accurate.


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  • #
    Raven

    Bugs,

    I did not say the thermometers were perfect – i said that temperatures estimated from wind speed using a climate model *cannot* be used to demonstrate that the climate model is correct.

    BTW – there is another explaination for the lack of a hot spot: the surface measurements have a warming bias. However, the climate modellers are not willing to look at that data because they like the numbers that the surface measurements give. As result they go looking for cooling baises in the balloon records. The selective nature of data corrections makes them all suspect.


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  • #
    Steve

    Bugs,

    Thermometers are NOT the problem! Siting them inappropriately, moving them without first normalizing for the site temperature difference, and/or converting to different technology without normalizing the differences are the problems. Don’t you read Watts?


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  • #
    BobC

    Craig Idso has a paper describing what he calls 8 “natural experiments” — situations which allow one to calculate the sensitivity of the climate to energy input. Michael has talked about 2 of them: day to night and winter to summer differences. Idso calculates the degrees C – to – energy relationship in each one of his 8 situations and comes to a similar conclusion: that the sensitivity of the climate to energy changes is about 1/2 to 1/3 of what the stefan boltzmann law (no feedback) predicts — thus indicating that the Earth’s climate system is strongly dominated by negative feedbacks. A link to the paper is here: http://members.shaw.ca/sch25/FOS/Idso_CO2_induced_Global_Warming.htm
    It is remarkable that all 8 measurements give very similar results, despite the extreme range of scale and time between them.

    Also, measurements of the Earth’s albedo (by satelites and by measuring the intensity of “Earthshine” on the dark part of the Moon) over the last few decades have shown a remarkable correllation between total albedo and global temperature. None of the current climate models can reproduce the changes in albedo, which alone can account for nearly the totality of temperature changes. Here is a presentation of the Earthshine-albedo data by a scientist at the Big Bear Solar Observatory: http://lasp.colorado.edu/sdo/meetings/session_1_2_3/presentations/session3/3_06_Palle.pdf

    Both Idso’s paper and the albedo-temperature correlation are experimental data that directly contradict the results of the GCM models used to predict enhanced global warming: Idso’s experiments falsify the climate sensitivity assumptions programed into the models, and the models fail to predict the magnitude of observed albedo changes which are sufficient to explain global temperature trends.

    Amy intelligent layman (or woman) can read these papers and get the main results — that the “Enhanced Anthropogenic Global Warming” hypothesis (AGW) is completely unsupported (indeed, contradicted) by measured facts.

    As others have pointed out here, AGW is also contradicted by historical records of Earth’s climate.


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  • #
    BobC

    I have a suggestion Michael: Why don’t you write up your calculations as a short paper and submit it to a number of websites who might be willing to post it semi-permanently. I would suggest this site, of course, also http://www.ICECAP.us, http://www.junkscience.com, http://www.co2science.org, http://wattsupwiththat.com/, for starters.

    Published in a downloadable pdf file, this would make a valuable reference.


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  • #
    Michael

    I have to say I find the posts here increasing frustrating. [NB: A lot of these comments were moved here from another thread to keep them on-topic, hence some references may seem oblique ---JN] You seem to be spending your time throwing insults at each other. Why? Do you really expect to change opinions by this action? The reality is that it just hardens everybody’s resolve. If you really want to progress the issue please focus on the science because that is the only possible way of resolving the issue. Please also keep an open mind, if you expect others to listen to your arguments be prepared to listen to theirs – only this way can one advance.

    One approach to the problem is to look at the past climate and CO2 record but that has been ploughed over so much and has been muddied so successfully that all sides claim it proves their point of view. I doubt if arguing from this perspective can ever be convincing to both sides. If we are to resolve the issue we need to find new ways to analyse the problem.

    The situation is confused because CO2 undoubtedly is a green house gas and increasing its concentration does undoubtedly increase the retained energy to some degree – the issue is how much. Some people see any increase as proof that AGW is real and dangerous. This is not a reasonable position because if doubling CO2 concentrations from pre industrial 280 ppm to 560 ppm were to increase temperatures by say 10 degrees C it would be extremely serious whereas if the increase were 0.01 degrees it would be completely irrelevant. What is critical is the size of the effect.

    Also we need to very carefully separate global warming from anthropogenic global warming. As just about everyone has pointed out, the Earth goes through almost continuous warming and cooling phases, another one now is not new and is not at issue. To demonstrate warming does not prove that CO2 is in any way responsible.

    WHAT NEEDS TO BE DETERMINED IS WHETHER OR NOT CO2 INCREASES ARE CAUSING DANGEROUS LEVELS OF GLOBAL WARMING.

    In my previous posts I tried to demonstrate that the direct effect of CO2 (in the absence of feedbacks) even using the IPCC data does not cause dangerous or even particularly significant warming. I think the IPCC (and many AGW supporters) agree with this. The claim is that the warming becomes dangerous due to positive feedback from water vapour.

    I believe that question is capable of a definitive solution and needs to be focussed on. One does not need to invoke extreme climate complexity and claim models as the only solution. I believe that well understood and very robust (dare I say traditional) science can provide the answer. I tried to give a brief analysis of this in my previous posts and show why I think such positive feedback is impossible (yes I admit I am sceptical of the AGW hypothesis). If others disagree, show where you think I have made an error or why my analysis is wrong. Alternatively outline your analysis for me to consider. I promise I will consider it carefully.

    Please put your efforts in this direction rather than dreaming up new ways to throw insults at each other.

    BobC, I saw your posts, the data on albedo is of extreme interest. A change from 0.297 to 0.310 represents a change in insolation of 4.5 watts/sq meter which is more than the total direct effect of doubling CO2. In fact from Stefan’s law it would imply a temperature increase of 0.82 C which is more than what we see for the entire 20th century!! The plot of albedo changes versus time does indeed seem to explain the temperature changes we have seen over the last 15 years of so. While I don’t for a moment question the integrity of the research or the researchers it would be extremely nice to have a second and independent group confirm the albedo numbers.

    I also take the point of your second post. I have been attempting to do exactly that without success but at your suggestion I will try again.


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  • #
    cmb

    107Michael:

    – Hi, Michael, and thanks for a well-reasoned post. I was beginning to depair. =) A couple quick points:

    The situation is confused because CO2 undoubtedly is a green house gas and increasing its concentration does undoubtedly increase the retained energy to some degree – the issue is how much. Some people see any increase as proof that AGW is real and dangerous. This is not a reasonable position because if doubling CO2 concentrations from pre industrial 280 ppm to 560 ppm were to increase temperatures by say 10 degrees C it would be extremely serious whereas if the increase were 0.01 degrees it would be completely irrelevant. What is critical is the size of the effect.

    – The problem here seems to be that the above assumes we don’t know whether or not the doubling would be harmful. In fact, we do know with almost complete certainty that it would result in large economic and societal costs, and some, perhaps considerable, loss of life. Further, from what I have found, every serious economic analysis indicates that those costs will dwarf the savings from avoiding action.

    Also we need to very carefully separate global warming from anthropogenic global warming. As just about everyone has pointed out, the Earth goes through almost continuous warming and cooling phases, another one now is not new and is not at issue. To demonstrate warming does not prove that CO2 is in any way responsible.

    – While technically true, we do know about Co2′s infrared optics, how much of it we are adding, and approximately how much energy it is withholding from escape to space.

    http://cimss.ssec.wisc.edu/goes/sounder_tutorial/gif/SPECTRA.GIF

    With that data we can make close guesses as to what warming we should be seeing. We also have empirical evidence of massive changes in our colder ecosystems, at a rate never before seen in human history.

    WHAT NEEDS TO BE DETERMINED IS WHETHER OR NOT CO2 INCREASES ARE CAUSING DANGEROUS LEVELS OF GLOBAL WARMING.

    – Last I heard, the Orbiting Carbon Observatory launches in a few months. It’s an interesting project which will all but solve the remaining questions there. And remember – we have hundreds of years to reach ‘dangerous’ – if it should take that long, the delay will not justify inaction. You might be interested in the US military’s report on AGW threat assessment.

    In my previous posts I tried to demonstrate that the direct effect of CO2 (in the absence of feedbacks) even using the IPCC data does not cause dangerous or even particularly significant warming. I think the IPCC (and many AGW supporters) agree with this. The claim is that the warming becomes dangerous due to positive feedback from water vapour.

    – Actually, no. The claim is that CO2 even taken by itself will eventually cause dangerous warming – in fact, that it may be doing so already. Water vapor is just a positive feedback (one of several), verified by new studies.

    http://news.nationalgeographic.com/news/2005/11/1110_051110_warming.html
    http://www.edf.org/documents/5596_GlobalWarmingWaterVapor_onepager.pdf

    Clathrate gun feedbacks:

    http://www.sciencedaily.com/releases/2007/10/071025174618.htm
    http://www.nature.com/nature/journal/v443/n7107/abs/nature05040.html

    Biosphere feedbacks:

    http://global-warming.accuweather.com/2009/01/once_a_sink_now_a_source_1.html
    http://www.sciencedaily.com/releases/2005/12/051213081446.htm

    Albedo feedbacks:

    http://news.bbc.co.uk/2/hi/science/nature/7692963.stm
    http://news.bbc.co.uk/2/hi/science/nature/4290340.stm
    http://www.guardian.co.uk/environment/2007/mar/16/climatechange.climatechange


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  • #
    Brad Jensen

    “Given that we know that AGW is real, and has a well understood physical basis, I think we need to react accordingly.”

    Well, since the temperature is falling, there is no GW, much less AGW.

    The amount of human-contributed CO2 in the atmosphere is one part in ten thousand. This is the same ratio as one penny out of one hundred dollars. AGW is the magic penny theory. The idea that one-one-hundredth of one-one-hundredth of the atmosphere is controlling the temperature of the planet is fantasy, not science.


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  • #
    bugs

    Here is some more science on CO2:

    That’s not science, that’s ignorance. His argument is about 40 years out of date. Let him look up the current research, then get back to us.


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  • #
    bugs

    As others have pointed out here, AGW is also contradicted by historical records of Earth’s climate.

    How long have humans been present in the geological record?


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  • #
    Phillip Bratby

    Michael,

    I agree with BobC. The sites he mentioned will definitely post your work and give it good exposure.


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  • #
    Raven

    Bugs says:
    “On a geological time scale, the current warming is extremely rapid”

    You have no conclusive evidence to support your claim. In fact, there is a lot of paleo-evidence that suggests that 1 degC swings over 100 years are extremely common events.

    Here are some ice core temperature records that illustrate this point:
    http://mclean.ch/climate/Eye_opening.htm


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  • #

    Bugs says:
    “On a geological time scale, the current warming is extremely rapid”

    Nope. As per The Skeptics Handbook: “Last century, temperatures rose about 0.7°C. But around 1700, there was a 2.2°C rise in just 36 years. (As measured by the Central England Temperature record).”

    I’ve also added inline comments to #126 and #132


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    Michael

    Given the attacking language I see on these posts I resolved that my previous post would be my last. However, I note that “cmb” (post 141) suggested that my post was full of I suspect’s, maybe’s and I don’t know’s without cites to any valid research. As a scientist I use cautious language because I recognise that there can be other points of view, other interpretations and dogmatic language stifles necessary discussion.

    I do not accept that a point has to be made dogmatically in order for it to raise issues that require explanation. Below is outlined an analysis which has been puzzling me. “cmb” you seem to be claiming very extensive and definitive knowledge of climate science. Could you please look at this analysis and explain to me where my error is. I would be most grateful.

    CONCERNS WITH THE KEIHL TRENBERTH MODEL

    Keihl and Trenberth in the Bulletin of the American Meteorological society http://www.cgd.ucar.edu/cas/abstracts/files/kevin1997_1.html (edition 78 1997 pages 197-208) presented a model of global energy flows for earth’s surface and atmosphere. It is my understanding that this model is used as the basis of the current global circulation models which predict dangerous warming from rising carbon dioxide. Analysing the Keihl Trenberth model from the point of view of spectroscopy suggests that this model raises some paradoxes.

    Three points are of particular interest in this model. The first is that according to the model convective and latent heat warming of the atmosphere amount to 24 plus 78 = 102 watts/sq M whereas radiative heating contributes 350 watts/sq M from the ground plus 67 watt/sq M from incoming solar energy (417 in total) suggesting that the predominant heating of the atmosphere (80%) is via radiation. This will be important later when discussing the atmospheric lapse rate.

    The second point is that the atmosphere is claimed to absorb 350 of the total 390 watts/ sq M emitted by the Earth’s surface. This suggests that the atmosphere is acting essentially as a black body (ie: absorbing at virtually all wavelengths) with an absorptivity and hence also emissivity of 350/390 = 0.9.

    There is no doubt that if the Earth is to remain in temperature equilibrium it must lose energy at the same rate as it gains energy. The energy gain is easily calculated from the radiant energy from the sun and the albedo of Earth and this translates to about 240 watts/sq M averaged over the Earth’s surface. It is my understanding that this figure is not in dispute. Thus the Earth must also lose 240 watts/ sq M to space and this can only be through radiation since the Earth is surrounded by vacuum. The Kiehl Trenberth model quotes 236 watts/ sq M which is in agreement with this.

    The Keihl Trenberth model suggests that 165 watts/ sq M of this originates from the atmosphere and this leads to the concept of a equivalent radiation altitude – a theoretical equivalent altitude within the atmosphere from which radiation escapes to space. Since, according to Kiehl and Trenberth, this surface is in effect a black body with an emissivity of 0.9 the temperature can be calculated using Stefan’s law (energy = emissivity * 5.67e-8 * T^4). For a radiated power of 165 watt/sq M and emissivity 0.9 the temperature is computed to be 240 K or -33 C. This temperature corresponds to an altitude of between 6 and 7 km, well within the troposphere. From my understanding, this concept of an equivalent radiation altitude is used widely in the global circulation models and indeed it is changes to this altitude combined with the known lapse rate that is used to predict surface warming or cooling.

    Herein lies the first paradox. The calculated equivalent radiation altitude inherently assumes that energy radiated from this surface can escape freely into space without impediment. If any of the radiated energy were blocked by higher altitude atmospheric components then this would reduce the amount escaping to space necessitating a higher initial radiative flux and thus a higher temperature hence a lower equivalent altitude. However at an altitude of 6-7 km the pressure is a bit under half the pressure at the surface of Earth. Thus what is being suggested is that the bottom half of Earth’s atmosphere absorbs almost all the radiation emitted while the top half absorbs almost nothing. The only way that could be true would be if the composition of the two halves were radically different. The difference suggested is the level of water vapour – water vapour content drops significantly with altitude. However while 6-7 km is above the low clouds it is below the region of the high level clouds. For clouds to be present shows there must still be significant water vapour content in the atmosphere. Thus water vapour content above 6-7 km is still significant and of course other greenhouse gases such as carbon dioxide and methane will certainly be present. Indeed, the IPCC prediction of a hot spot in the tropics at an altitude of 8-10 km is based on the energy released from condensing water vapour inherently implies significant water vapour above 6-7 km. This means that free radiation to space or even anything remotely approaching such a situation from an equivalent radiation altitude of between 6 km and 7 km is not possible.

    Further, as stated above, radiation and absorption of electromagnetic energy are reciprocal processes and are controlled by the same emissivity factor. Thus an atmosphere which absorbs nothing is also not capable of radiating. If the atmosphere at the equivalent radiation altitude acts as a black body with an emissivity close to 1 it must also absorb strongly. There is no obvious mechanism which could account for an abrupt discontinuity in emissivity at the equivalent radiation altitude.

    A second paradox comes about when one considers the atmospheric lapse rate (temperature versus altitude profile). If the temperature of the atmosphere at any altitude is to be stable, the absorbed energy must equal the radiated energy. While the absorbed energy is independent of temperature, the radiated energy is very strongly dependent on temperature (as shown from Stefan’s law) hence the temperature will adjust until the radiated energy matches the absorbed energy and this in fact defines the lapse rate. The Keihl Trenberth model implies that 80% of the absorbed energy is from radiation (as already mentioned in the second paragraph of this article). If the atmosphere above the equivalent radiation altitude is not absorbing any energy from below, that should be reflected in an abrupt drop in temperature when passing through the equivalent radiation altitude. However the lapse rate is known to be progressive and uniform up to at least 10 km altitude.

    What is the significance of all this? Well if the GCM’s use the Keihl Trenberth data and it is not accurate it calls the models into question. Specifically, the above analysis implies that the greenhouse effect of the atmosphere and water vapour in particular may not be as large as the model implies.


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    Phillip Bratby

    Michael:

    I have read your articles with great interest (and have saved them to a separate file for future ease of reading and reference).

    I sincerely hope that the “attacking language” of only one or two persons does not put you off further contributions. As a physicist, I am entirely happy that your discussion of a very complex topic is full of ‘maybes’ etc. I certainly would not expect you to state your views in a dogmatic fashion.

    The thing I have noticed about cmb is that he just dismisses other views as ‘made-up crap’ or just quotes a link or reference (I think he must have a file full of standard phrases to use and dubious references; an example is a link to a 1-page brochure by Environmental Defence which, amongst other things states ‘Water vapor is part of a vicious cycle. As humans emit greenhouse gases like CO2, the air warms and holds more water vapor, which then traps more heat and accelerates warming. In fact, scientists calculate that changes in water vapor double the climate’s temperature response to increasing CO ’and ‘Scientists are confident that the warming cycle involving water vapor is real because climate model simulations are very close to actual water vapor and temperature measurements’). Does he expect you to accept that? What use is a reference like that to anyone with a serious interest in the science? Perhaps that is the depth of his scientific understanding. He does not give scientific answers or arguments, or even asks direct questions. He is purely dismissive in a dogmatic ‘I am right and you are wrong’ way. He wants you to give up your postings. There are far more people out here who are interested in what you have to contribute than there are people who just wish to denigrate anyone whose views are counter to theirs. So please don’t give up on the basis of people like cmb.

    It will be interesting to see if anyone here comes up with any scientific arguments against anything you are saying. Again, I would like to ask you to you pull together everything you have put down and create a single posting for a site such as ICECAP or any of the others mentioned by BobC at #92.


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    Raven

    Micheal,

    David Stockwell has a good site for technical discussions alternatives to the “consensus” model of GHGs
    http://landshape.org/enm/

    He has set up a wiki covering the theory Dr. Ferenc Miskolczi which also disputes the “consensus” model of GHGs:
    http://www.landshape.org/dokuwiki/doku.php?id=introduction

    Some of the contributors have gone as far as developing experiments to determine if predictions made by Miskolczi’s theory come true (they appear to do so).


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    Michael

    Thanks Raven I will have a good look at the links you cite.


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    Mike Davis

    Michael:
    I appreciate a well balenced scientific approch and enjoy the ideas you bring to the discussion. I have not said any thing as I sort of enjoy food fights.
    While I was working it was once said of me: Arguing with Mike is like arguing with a pig in the mud. In the end you only get dirty and the pig/Mike enjoys it.
    Raven:
    While I appreciate yiur input on the sites where I have seen it. I personally feel that you and those that you currently site have a tendency to go overboard the other way. I tend to have a neutral approch: That nature is doing just fine but we have a tendency to not care for anything that is not within our reach at the moment. (Speaking of the mass in general. Not signalling anyone here idivually. I do not personnaly know you and cannot read minds) It seems that the best way to get attention is to predict dissaster of somekind and better yet place the blame on some other group. Such People blaming USA as primary emmiter causing GW. This device has worked well during history to provoke wars and hatred.
    Having said all that. I do enjoy seelng other views so carry on! Live with what you feel is right.


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    Michael

    I thought I should explain why I thought an analysis of the Kiehl Trenberth model worthwhile. It suggests that the majority of the long wave radiation out to space comes from the atmosphere. If that is true, then the point in the atmosphere from which the radiation emenates must stay at the same temperature otherwise the total radiation to space would change. The GCM,s then go on to calculate that an increase in GHG raises the effective radiation altitude (which is undoubtedly true working from the above stated starting point) and for the same lapse rate the surface temperature and the atmospheric temperatures will all increase although the increase would diminsh with altitude.

    As an aside, I disagree with the concept of an equivalent radiation altitude. My analysis suggests that radiation from the atmosphere in principle only occurs from the very top of the atmosphere although the actual height varies for each wavelength – in fact radiation at each wavelength only occurs from the top 1-2 absorbance (at that wavelngth) of the atmospheric column.

    My calculations further suggest that there is considerable radiation from the surface and far less directly from the atmosphere. The surface radiates directly to space at wavelengths where the atmosphere does not absorb. As the greenhouse gas concentration increases, the proportion radiated from the atmosphere decreases and the portion radiated directly from the surface must increase to compensate (which means the surface temperature must increase). If the radiation from the atmosphere decreases it implies that the top of the atmosphere must cool. That in turn means that increasing the green house gas concentration should cause the surface and the lower atmosphere to warm but the lapse rate will also increase with the effect that the upper atmosphere would cool. It seems to me that this is a difference which can be determined experimentally.

    I realise that the above is going to be frustrating because I haven’t disclosed my calculations. I did try but unfortunately I find this blog does not seem to want to accept diagrams and without the diagrams I suspect the analysis is not comprehensible. Any thoughts on how I can put up the analysis with diagrams would be very gratefully accepted


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    What no counterpoint posted here?

    Well I like this:

    “Santer uses statistics to show that the hot spot might be hidden under the noise. He hasn’t found any sign of warming–just the sign of fog in the results. Sherwood ignores the thermometers altogether and uses wind gauges to tell us the temperature. (Who’d a thought?!)’

    If it is the noise zone as he say.Then that will kill the hotspot search since it is not visible.Imagine that he comes up with that lame reasoning.First it has to be VISIBLE for it to support “the CO2 did it” modeling run.I thought he WANTED to support the AGW angle.Instead he shoots himself in the foot.What is wrong with him?

    The other guy discards temperature readings because it is not supporting the hotspot search.Tried a wind gauge instead and then make inferences from the wind data.I find that hilariously imaginative.Now if he can con a few hundred people over the bogus approach.Then maybe he created a new flytrap?

    No wonder I am still a skeptic after 25 years.


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    Michael

    Further to my last posting on an equivalent radiation altitude.

    If a material absorbs light, one might intuitively expect the amount of light absorbed to be proportional to the concentration of the material, so that doubling the concentration doubles the amount of light absorbed. This is not the case as can be seen by a simple thought experiment. Imagine we have a piece of material which absorbs 50% of the light incident on it transmitting the other 50%. Doubling the concentration of material is exactly equivalent to adding a second identical piece of the material behind the first piece. We already agreed the first piece absorbs 50% of the light incident on it transmitting the remaining 50%. The second piece being identical does exactly the same, absorbing 50% of the light that passed through the first piece and transmitting 50%. Thus the net light passing through the two pieces is not 0 but 25%. If we have n identical pieces the transmission will be 0.5n.

    Thus the relationship between concentration and light absorbed is not linear. Spectroscopists use the term absorbance to define the degree to which a sample absorbs a particular wavelength of light. This term is defined by the equation;

    Fraction of energy transmitted = 10^(-absorbance)
    and Fraction of energy absorbed = 1 – 10^(-absorbance)

    If a sample has an absorbance of 1, it means that it absorbs 90% of the light incident on it, transmitting the remaining 10%. The absorbance of a sample is directly and linearly proportional to the amount of absorbing material in the light path (Beers law). Thus if a particular sample has an absorbance of 1 then doubling the concentration of the absorbing species for the same path length or doubling the path length with the same concentration will change the absorbance to 2.

    This by the way is basic spectroscopy, known and repeatedly proven for 100+ years and the basis of of a huge chemical analysis industry. The chance of this being in error is approximately zero.

    Now take the case for carbon dioxide. The absorbance of the total atmospheric column of carbon dioxide at 280 ppm s about 2000 absorbance. Imagine we take just a very thin outer shell of our atmosphere such that the carbon dioxide in that shell has an absorbance of 2. Then, at the absorbing wavelength of carbon dioxide (14 microns) it will absorb 99% of the energy radiating up from below. Thus it is effectvely opaque at 14 microns. The only energy at 14 microns which will radiate out is energy emitted by this outer layer. For a well mixed atmosphere that would mean the only energy radiating out at 14 microns is energy emitted by the last 100 pascals of the atmosphere. Thats way beyond the troposphere.

    We can go further, imagine we look at the topof the troposphere – altitude about 10 km. Take a 2 absorbance layer at this altitude (this would be a meters thick). Again this layer will block all 14 micron radiation from below. The 14 micron radiation emanating upwards will be energy radiated by this layer whihc is controlled by the temperature at this altitude. But that temperature is far too cold to match the claimed emission from the equivalent radiation altitude. Of course this is all only for CO2 and hence 14 micron radiation. The same argument however applies to water vapour and its absorption wavelengths (although the assumption of a well mixed atmosphere does nto apply, water vapour levels beyond the troposphere can be very low).

    This is why I disagree with the concept of an equivalent radiation altitude and believe it leads to wrong results.


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    Michael

    Opps, just looked at the last post, the posting changed the format. Where it says fraction of energy transmitted the -absorbance bit should be superscript ie: the right hand term should read 10^(-absorbance) NOT 10 – absorbance. similarly also with the subsequent line.


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    Larry

    Michael:

    I, too, enjoy reading your contributions! Please stick with us here. I think there are more folks reading and following all of this than you would believe. Have you read and analyzed “Response to Arthur Smith’s Critique of Christopher Monckton’s ‘Climate Sensitivity Reconsidered’” by Christopher Monckton at the SPPI site?

    Today from Pravda! Earth on the Brink of an Ice Age

    http://english.pravda.ru/science/earth/106922-earth_ice_age-0#

    This a rather succinct view of the state of Global Warming/Climate Change. It supports most everything I have been reading the past three years. It is rather ironic that it comes from Pravda! It is time for our US newspapers to wake up and smell the “cool” air!!!


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    Michael

    I seem to be spending lots of time on the computer this morning. In the light of my previous posts, I was reviewing the temperature versus altitude data for our atmosphere

    http://www.atmos.washington.edu/2005Q4/212/Lecture6Notes,pdf

    This shows the linear drop in temperature throughout the troposphere down to about -60C at the tropopause and then the rise in temperature through the statosphere up to nearly 0 C at 50 km altitude – about 1 torr or 100 pascals pressure. Question, what causes the rise in temperature?

    From previous discussions one would assume that it is established by radiative balance. But its getting warmer with altitude, that means greater radiation as one goes up higher, a paradox? No its not! As the diagram points out the stratosphere is rich in ozone which is a very good absorber of short wavelength radiation from the sun. This absorption of energy will warm the air but nowhere near the point where it can be re-emitted as short wavelength radiation (that would require temperatures of 1000′s of degrees). The energy can only be emitted as long wavelength radiation and only at wavelengths where the atmosphere has a high emissivity. This means the short wavelength energy absorbed from incoming sunlight is absorbed an re-radiated at the greenhouse gas absorption wavelengths. As many have pointed out, the water vapour content of the air falls rapidly through the stratosphere and as it does so the available emission wavelengths also diminish. Eventually I suspect that CO2 (along with some contribution from methane) becomes the dominant long wavelength mission mechansim.

    In effect, we are seeing the upside down version of the troposphere. The energy comes in from the top and the temperature correspondingly rises as one goes up. The interesting point is that the temperature peaks at about 100 pascals, which is what we calculated is the dominant emission point for 14 micron emission from CO2. Of course that could be a total con-incidence but it is as least consistent.

    Could all this be incrasingthe downward radiation to earth’s surface? No becuase now all the greenhouse gas below acts as a blanket blocking radiation of this energy down to the surface – it works both ways.

    If all this is correct, we should be looking at the greenhouse impact on Earth’s surface by considering the energy radiation from the tropopause ie: at 10 km altitude. Why this altitude? Because it is the minimum temperature point. It thus marks the point of minimum radiation from below and above and the point of separation of these two effects.

    This seems to me a very interesting and in fact a vital point and one which is worth debating and getting resolved. I am most interested to hear the thoughts of others on this issue.

    By the way, I note there were no other posts in the last day. I hope I am not intimidating others with my posts. PLEASE tell me if I am.


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    Michael

    I really am dominating the blogs this morning bt I had a further thought I just had to share.

    It think it is really very significant that the temperture at the tropopause is a local minimum. Consider, the temperatures above and below are both warmer. How does this region manage to remain colder than all the surrounding regions. For this to be the case there asolutely must be some form of heat sink and from thermodynamics this heat sink must be colder than the region from whcih heat is flowing. The only candidate is space. That means the tropopause must be able to radiate directly to space. But in an earlier post I said that radiation from lower layers ofthe atmosphere will be blocked by the higher layers. That must need some qualification.

    Another thing, the tropopause represents a temperature inversion -warmer above not cooler. Temperature inversions block convection for obvious reasons. But water vapour is carried up via convection from the surface so at the tropopause there is in fact a mechanism whereby there could be a rapid change in water vapoour content. If so, the stratosphere could be so low in water vapour that it does not fully block the emission from the water vapoour bands and this could be the mechanism cooling the tropopause.

    That argument cannot however apply to CO2 since the atmosphere is reasonably well mixed whihc means there is substantial CO2 abovethe tropopause. If so it implies the tropopause gets more energy at the CO2 absorption lines from above than it emits since the regions above are warmer. This additioanl energy comes from sunlight absorbed in the stratosphere not from energy reaching earth’s surface. It suggests that in balance, none of the surface energy radiated back out to space by the atmosphere is radiated at the CO2 absorption lines – only at the water lines. There is still emission at the CO2 lines but it emanates from the stratosphere and is powered by sunlight absorbed in the stratosphere.

    If that were the case, it would imply that all the energy at the CO2 lines emitted by earth’s surface will be blocked. None of it radiates back out to space. Does this have implications for the sensitivity of surface temperatures to CO2?


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    Mike Davis

    Michael:
    The way you are describing it means that the model do not know what they are talking about.


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    Michael

    Don’t know Mike and I am cautious about being too dogmatic. All I am doing is giving an analysis which involves some hypothesising on my part but is largely based in pretty well known and proven science. It certainly has some very interesting implications if true. I do have very grave reservations about the concept of an equivalent radiation altitude but then again maybe I am missing something, maybe the model makers know all about this and then again maybe they don’t and these are original thoughts. The whole point of puttng these posts up is to circulate the concepts and stimulate others to think about them. Ideally we need to come up with some predictions which are experimentally testable and can be used to verify or debunk the ideas; like the one about the top of the atmosphere cooling.


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    Raven

    Micheal,

    If you are looking for a sanity check try here:
    http://www.realclimate.org/index.php/archives/2007/06/a-saturated-gassy-argument/
    If you are onto something then you should be able to explain where their arguments are wrong.


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    Michael

    Hi Raven;

    I read the text of the link in your first post. It’s not all wrong but I found many issues that I question. Firstly they say the absorption experiment was done in a 30 cm tube which was longer than the required 250 cm tube. According to my calcs 250 cm is about right but that is far longer than 30 cm not shorter. The experiment is meaningless because it inherently ingores emission and specifically repeated absorption and reemission (because spectrophotometers only measure energy transmitted on the original axis). The article says the level of CO2 is no where near what would be required for “saturation”. Hmm the atmospheric CO2 column at 280 ppm exhibits 2000+ absorbance units – I have to disagree with the writer.

    In Para 6 they claim that if more CO2 is added all layers below have to get hotter so that the outermost layer remains at the same temperature to match radiation balance. No the proportion of the radiation from the surface increases and the outermost layer gets colder – the atmosphere radiates less.

    A bit later the article comments that CO2 is well mixed in the atm while water vapour is the stratosphere is exceptionally low. Wow a corroborating reference for 2 of my assumptions and from a warming advocate.

    Further the article comments that changes to CO2 and H20 only shift the layers where the main action occurs – everything below is irrelevant. I think this is simplistic but it also directly contradicts the equivalent emission altitude used by the GCM’s – interesting. Further the altitude they talk about is the “top” of the atmosphere which is certainly not at 5-6 km with half of Earth’s atmosphere above. Also, the whole analysis ignores the effect of incoming solar energy absorbed by the atmosphere which is the point of my most recent posts. In what I wrote it would be that effect which changes the situation.

    The article does mention 4 watts/sq M from doubling CO2 – another approximate confirmation with what I claimed in a very early post.

    It also claims 1% increase in energy is significant after all 1% increase in temperature is 2.8C. He is forgetting the T^4 in Stefan’s law, a 4 watt/sq M increase in energy gives only 0.7C increase in temperature.

    There are many more issues I would take up with this article to long to list here. It is a slick plausible sounding dissertation which skilfully glosses over many inaccuracies and paradoxes hard to find unless one knows the science well and reads carefully.

    Major issues, ignores changing balance between atmospheric and ground emission, ignores effects of direct atmospheric absorption of solar energy. Does not consider the lapse rate data. I don’t see that this article in any way contradicts the hypothesis I outlined in recent posts.


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    Raven

    “A bit later the article comments that CO2 is well mixed in the atm while water vapour is the stratosphere is exceptionally low. Wow a corroborating reference for 2 of my assumptions and from a warming advocate.”

    The radisonde data indicates stratospheric cooling as predicted by the GHGs but the tropospheric warming is missing. An incorrect understanding of the effect of water vapour would explain this discrepancy if water vapour has no effect on stratosphere temperatures.

    “The article does mention 4 watts/sq M from doubling CO2 – another approximate confirmation with what I claimed in a very early post.”

    My understanding is line by line calculations have confirmed this in a number of studies.

    “There are many more issues I would take up with this article to long to list here. It is a slick plausible sounding dissertation which skilfully glosses over many inaccuracies and paradoxes hard to find unless one knows the science well and reads carefully.”

    It would not be the first time that real climate posted claims that were technically wrong but sounded good.

    I would also recommend looking at Roy Spencer’s work on clouds. He is focused more on the clouds as climate forcing but his work is very much related to the tropospheric energy transfers.
    http://www.drroyspencer.com/

    He suggests that random variations in clouds are forcing in themselves that have been neglected:
    http://www.drroyspencer.com/research-articles/satellite-and-climate-model-evidence/

    Also, a new study has come about earth albedo:
    http://climatesci.org/2009/01/02/new-jgr-paper-inter-annual-variations-in-earths-reflectance-by-palle-et-al-2009/

    There was apparently, a step change in albedo around the 1998 el nino but after that it has been constant. Bad news for the people promoting a cosmic ray-climate link but good news for people who think clouds have a much bigger effect.

    A couple other sources:

    Some very interesting a data on water vapour: http://junkscience.com/Greenhouse/moisture.html
    Someone else’s take on CO2 sensitivity: http://junkscience.com/Greenhouse/What_Watt.html


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    –By the way, I note there were no other posts in the last day. I hope I am not intimidating others with my posts. PLEASE tell me if I am.–

    No but the scary pink mask icon you use that appears at the beginning of each of your posts is freaking me out a little.


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    –The article says the level of CO2 is nowhere near what would be required for “saturation”. Hmm the atmospheric CO2 column at 280 ppm exhibits 2000+ absorbance units – I have to disagree with the writer.–

    For those of us who have never owned a pocket protector, I’d like to restate this and have you tell me if my understanding is accurate.

    (I just realized most of the people on the Internet probably don’t even know what a pocket protector is.)

    Saying that the amount of CO2 in a column of air from the surface to space, contains 2000 times the CO2 needed to absorb all the radiated energy in the wavelengths it is sensitive to.

    The first concept here, is that each kind of molecule (such as CO2) absorbs only a part of the radiation – sort of like having your radio tuned to a specific frequency.

    The second is that the amount of CO2 in the air is already so large that it absorbs all the available energy at the wavelength it is ‘tuned’ to. Adding more CO2 can only absorb more energy, if the amount of energy being radiated (by the sun, initially) goes up. The radiation from the sun would have to increase by 2000 times before you would see any more difference from an increase in CO2 levels. You could raise the amount of CO2 by a factor of a thousand and it would make no difference, since the amount that existed before you started would already be absorbing all the radiation that is available.

    Do I get a smile and a pat on the head, or do have to take the pointy hat and sit in the corner?

    Brad Jensen

    PS I did own a set of Napier’s Bones.


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    Mike Davis

    Brad:I did wear a pocket protector for more than 30 years.
    Michael: Which weighs more 2 hydrogen and 1 oxygen or 1 carbon and 2 oxygen? Or are the 2 oxygen molicules acting as wings allowing the CO2 to fly higher like a bee? See I do not remember my perodic table but I think hydrogen is 1 and 0xygen 16 =H2O 18 & carbon 12 + oxygen is 2×16 = CO2 44. Must be the wings that allow that molecule of CO2 to be higher in the air??? MAGIC?


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    Michael

    Hi Brad;

    about the mask, the system adds this and it makes the selection so apologies but I plead not guilty. With regard to your second post. Sort of bt not quite. If one goes back to my post 172 where I explain about the term absorbance, 280 ppm of CO2 in the atmosphere has an absorbance of more than 2000. If that were the only effect it would mean that at the wavelength where CO2 absorbs (yes like having ones radio turned to the right wavelength) it would only transmit 10^-2000 of the incident energy what ever level that was. 10^-2000 is an absolutely excellent approximation to zero. Unfortunately absorption is not the only effect occuring. The atmosphere also emits infra red energy by virtue of its temperature. The effect is that energy at 14 microns (the wavelength where CO2 absorbs) is being continuously absorbed and emitted throughput the atmospheric column. I have calculated the nett effect of this more complex process and find that the net energy radiated at the absorption line for a gas with absorbance N is not 10^-N but instead 1/(N+1). It is this calculation I wanted to post earlier but requires diagrams. I should add here, that Joanne got back to me very quickly with a way to post with diagrams so I have no excuse for not doing so except the plea of other work and simple laziness. I will give it a go soon.

    Now for CO2 that would mean the fraction of 14 micron energy radiated to space is 1/2001 or about 0.05% which as an engineer I regard as a reasonable approximation to zero. Further more, doubling the CO2 concentration yields 4000 abs and energy radiated to space of 0.025% (to use questionable language half of stuff all change). So is this the whole story? Alas no. The absorption lines of gasses do nto have infinitely steep sides. This means that even while the line centre may be saturated, the outer portions of the wings of the lines may not be. As the concentration increase the absorption in these wings will increase slightly. This is called line broadening and it is this which casues the log linear relationship between concentration and energy retained. Does this make it clearer or murkier?

    Mike, with reagrd to your post. You are completely correct H2O has a molecular weight of 18 whereas CO2 has a molecular weight of 44. Thus CO2 is heavier and, while you do not state it explicitly, I think you are implying it should sink down in the atmosphere. Indeed one can do experiments which show this. Place a lighted candle in a beaker (better place it and then light it, saves burnt fingers), take a beaker of CO2 and carefully pour it into the beaker with the candle. As you pour the candle will abruptly go out showing that the CO2 can be successfully poured from one beaker to another. So my assumption must be wrong? No because you have not taken into account diffusion through random motion of molecules. This dominates over the difference in molecular weight and ensures the atmosphere is well mixed. The same thing happens in a fog or in clouds. Liquid water is clearly far more dense than air, yet if the water particles are small enough they remain suspended in air more or less indefinitely. It is not until the particles get large enough for gravitational effects to dominate over diffusion that the droplest fall as rain. Even very tiny water droplets are far far larger and heavier than CO2 molecules which gives an idea of how far diffusion dominates over gravitational effect for CO2 moelcules.


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    Mike Davis

    Michael:
    It was probabley a poor attempt at a joke. I under stand diffusion and mixing in the atmosphere.I also flew Kites of many styles. I also know that according to models that a bumbble bee can not fly. At least once upon a time they were not supposed to be able to. All of that asside I do appreciate your imput.


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    Michael

    Here is a thought provoking concept for comment. It sort of follows on from my post 176.

    Imagine we divide the greenhouse gases into two parts, firstly water vapour and secondly everything except water vapour. The first is non uniformly distributed through the atmosphere. According the AGW advocates it’s concentration diminishes very rapidly beyond a certain altitude and is exceptionally low in the stratosphere. In fact this is entirely plausible since the tropopause represents a very significant temperature inversion which would block convection, a major way in which water vapour is carried upwards. All other greenhouse gases however would be relatively uniformly distributed throughput the atmosphere due to diffusion.

    This means we have a troposphere containing all greenhouse gases and a stratosphere containing all greenhouse gases except water vapour with a reasonably rapid change at the tropopause.

    Now since there is a temperature inversion at the tropopause it means the temperature gradient at this point becomes zero. It is not possible to have net radiative heat flow with a zero temperature gradient the amount radiated down and up become exactly equal. Does that imply that there can be no atmospheric radiative energy loss through the tropopause? No it doesn’t because of the change in atmospheric composition at this point. From below, heat is radiated at the emissive wavelengths corresponding to all greenhouse gases including water vapour. From above the only wavelengths available are those for all greenhouse gases except water vapour. Emission at these wavelengths is cancelled by the corresponding emission from below but the water vapour emission is not cancelled. This means the only radiative loss from the tropopause is at the water emission wavelengths. In fact something like this MUST be occurring since the tropopause is colder than regions above and below which means it has to have a mechanism of losing heat to an even colder sink – space is the only candidate.

    Does this mean there is no emission to space from the other greenhouse gases? No it doesn’t because the stratosphere is absorbing energy directly from the sun (eg: ozone absorption lines) and this energy will be radiated at the emission lines of these GHG’s.

    The AGW advocates also state quite correctly that atmospheric emission to space only occurs from the top of the atmosphere because emission from lower down at the GHG lines is blocked by the gas above. This means that net atmospheric emission of energy originating from Earth’s surface only occurs from the tropopause and at the water emission lines. Stratospheric emissions have no effect on this what so ever because they are at different wavelengths and there is a zero temperature gradient at the tropopause which means zero radiative energy transfer across this point for non water vapour greenhouse gas components.

    The only mechanisms for energy loss from Earth’s surface to space are thus via direct radiation from the surface and radiation from the tropopause at the water emission wavelengths.

    Now the sum of all greenhouse gases in the troposphere has many absorption lines well spread over the mid infrared spectrum. The emissivity/absorptivity at these lines is approximately 1 and the emissivity/absorptivity between the lines is about 0. If we assume the absorption lines occupy a fraction Kof the total wavelength span (where K is between 0 and 1) then the emission from the surface direct to space can be approximated as 390 *(1-K) watts/sq M. Emission from the tropopause is approximately the black body radiation * K, less the contribution of the lines from greenhouse gases other than water vapour. Since we know the total emission must be 240 watts/ sq M and we know the tropopause is at about 213 K (-60C) we can make an estimate of K.

    The black body emission from 213K is 117 watts/ sq M. The emission from the tropopause is less than 117*K because we need to subtract the contribution of GHG’s other than water vapour. Water vapour represents about 70% of the total GHG effect thus the net emission from the tropopause is about 117 * K * 0.7 or abut 82*K.

    Thus 390 * (1-K) + 82 * K = 240 from which it follows that 390 – 240 = (390-82)*K
    And K = 0.49. That means the emission from the surface is 200 watts/sq M and emission from the tropopause is about 40 watts/sq M.

    This is a very long way from the Keihl Trenberth numbers which claim 165 watts/sq M from the atmosphere. 165 watts/sq M is greater than the black body emission from the tropopause so it is hard to see how it can be reconciled with the above analysis. If the Keihl Trenberth numbers greatly exaggerate the green house effect and they form the basis of the GCM’s maybe the GCM’s similarly exaggerate the greenhouse effects in our atmosphere.


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    Phillip Bratby

    Michael:

    When I look at the K&T ‘energy budget’ figures it seems that the way the radiation fluxes (direct from ground to space (40) and from top of atmosphere to space (165)) may be calculated is based on a ‘tuned’ climate model (for which they don’t reveal the details other than to say it uses the Malkmus model) and some arbitrary assumptions (described as ad hoc). The figure of 165 only appears in the final graph, not the text and there is no explanation where it comes from. Is it the figure that is left when all the other radiation fluxes have been calculated? K&T do not seem to give any physical explanation, just the results. I find their paper very opaque and unsatisfactory.

    Your calculations are based on the straightforward physics of spectroscopy and seem logical.

    Am I missing something in the K&T paper? Do you need to see what is in the Malkmus model to find out why their results are so different from yours?


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    OldJoe

    Michael: Re: posts on “…_intimidate_a_skeptic”

    It is a pleasure to see a scientific and literate discussion on the subjects(s) under consideration
    here. I have some comments:

    Please, by all means, write up your thoughts and calculations. Get them published in whatever fashion
    will result in the widest possible dissemination. Perhaps Ms Nova could help with that?

    There are a couple of German scientists(?) who are doing the same thing. Maybe if enough thoughtful
    and educated people will chip in, we can begin to pile up such a weight of “evidence” that some
    modelers will go back to basic principles and develop models from there. (not holding my breath!)

    I am following your arguments generally, however I could use some educating in thermodynamics, etc.
    Could you supply a reference that would be accessible to someone with enough graduate math and statistics to qualify to teach them in a community college? I would not resent a little hand-holding.

    many thanks, and keep ‘em coming

    OldJoe


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    Michael

    Back at work and extemely busy which is why I have not been posting. Also I am trying to put my thoughts into a single more coherent document. OldJoe, I saw your query. All I can really suggest is a good first year uni physics text book. These usually provide a reasonably good basic coverage of thermodynamics. Anything more becomes specialised text book and I am too far out of date with recent publicatons to make any meaningful suggestion in that area.

    CMB, some time ago I posted a number of theoretical analyses of Earth’s atmosphere based on the highly relevant science of spectroscopy. If true, these very strongly suggest serious if not fatal flaws in the theory underlying the GCM’s – a major basis of the AGW clams. I asked for you comments on these- specifically can you point out errors in my analysis. I have not seen any reply. I ask again, please consider what I have written and point out explicitly where my errors lie. I am not interested in name calling, I am very interested in the science. Only by studying and debating this can the issue be resolved.


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    cmb

    CMB, some time ago I posted a number of theoretical analyses of Earth’s atmosphere based on the highly relevant science of spectroscopy. If true, these very strongly suggest serious if not fatal flaws in the theory underlying the GCM’s – a major basis of the AGW clams. I asked for you comments on these- specifically can you point out errors in my analysis. I have not seen any reply. I ask again, please consider what I have written and point out explicitly where my errors lie. I am not interested in name calling, I am very interested in the science. Only by studying and debating this can the issue be resolved.

    – I am allowing myself another post here to mention that Japan’s carbon monitor satellite was successfully launched a few days ago, and America’s will be (we hope) a few weeks hence. Such debate, which generally operates within the gaps left by current work, will soon be unnecessary once we have verified spectrographic analysis from every point covered by their detectors. Your questions regarding Kiehl-Trenberth, and other radiative budget concerns like variation in H2O feedbacks, should be answered in detail.

    One side or the other in this controversy is about to receive the count of three, possibly by the end of the new year, and pencil-whipping on blogs won’t amount to much on either end by then. Whether the losing side admits it will be another matter. =)


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    Stephen Wilde

    I do hope that those satellites resolve the issue but in the meantime I’ll go out on a limb and set out what I think is going to be the outcome of all this debate when the new evidence has been carefully considered:

    http://co2sceptics.com/news.php?id=2581


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    Phillip Bratby

    Michael:

    Yet again cmb failed to answer the question. Has he answered any question except by refering to something else?


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    cmb

    Stephen Wilde:

    (from your link)

    If downwelling longwave radiation warms the water surface then any energy added to the water surface is taken away by the latent heat of evaporation.

    – Hi, Steve. I can find no principle which dictates the complete removal of the energy by vaporization. What might that be?

    Neither air nor downwelling radiation are able to warm water because the evaporative process always uses the energy supply most readily available and if the water is warmer than the air it is taken mainly from the water and any warming effect negated.

    – Similar question here. There is no doubt in the real physical world that air and radiation are both capable of warming water (as a bachelor, I cook.) Again, what am I missing?


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    cmb

    Phillip Bratby:
    January 31st, 2009 at 6:20 am
    Michael:

    Yet again cmb failed to answer the question. Has he answered any question except by refering to something else?

    – Can’t you read?


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    Stephen Wilde

    cmb

    Air in the open as opposed to a closed environment cannot heat water. Any extra energy whether from conduction or downwelling infra red radiation just increases the rate of evaporation which, because of the water’s loss of the rather large latent heat of evaporation,eliminates any warming effect from the extra energy.

    Latent heat
    From Wikipedia, the free encyclopaedia

    In thermochemistry, latent heat is the amount of energy in the form of heat released or absorbed by a chemical substance during a change of state (i.e. solid, liquid, or gas), or a phase transition.[1][2]
    The term was introduced around 1750 by Joseph Black as derived from the Latin latere, to lie hidden. The term has now been replaced by “enthalpy of transformation”.
    Two latent heats (or enthalpies) are typically described: latent heat of fusion (melting), and latent heat of vaporization (boiling). The names describe the direction of heat flow from one phase to the next: solid → liquid → gas.
    The change is endothermic, i.e. the system absorbs energy, when the change is from solid to liquid to gas. It is exothermic (the process releases energy) when it is in the opposite direction. For example, in the atmosphere, when a molecule of water evaporates from the surface of any body of water, energy is transported by the water molecule into a lower temperature air parcel that contains more water vapor than its surroundings. Because energy is needed to overcome the molecular forces of attraction between water particles, the process of transition from a parcel of water to a parcel of vapor requires the input of energy causing a drop in temperature in its surroundings. If the water vapor condenses back to a liquid or solid phase onto a surface, the latent energy absorbed during evaporation is released as sensible heat onto the surface. The large value of the enthalpy of condensation of water vapor is the reason that steam is a far more effective heating medium than boiling water, and is more hazardous

    As stated above the change in state requires the addition of new energy over and above the energy required to provoke the change in state.
    That is the latent heat of evaporation and it is very large
    Evaporation goes on whether or not additional energy is added to a water molecule, because of the different densities of water and air. Adding extra energy from IR or anything else just accelerates a process that is going on already.
    Latent heat of evaporation has to come from somewhere and it is extracted from the surroundings i. e. from nearby molecules of water or air.

    I don’t see the relevance of cooking. The water in a pan is heated from conduction through the pan base by a heating element. Have you ever tried boiling a kettle with the heating element outside and above the water surface? If you tried the evaporation from the surface would cancel out all the radiative energy from the heater and the water would get no warmer.

    You need to give me a plausible mechanism whereby radiation in the open air can heat water and it must be specifically infra red radiation which is unable to penetrate the water surface. Other wavelengths can do it but not IR so AGW theory has a serious unaddressed problem in my opinion.


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    Phillip Bratby

    Stephen Wilde:

    A nice explanation. As someone who worked for years in an industry turning water into steam, I was always struck by how little understood was the magnitude difference between sensible and latent heat. Most people have no idea of the power of latent heat (if that is not mixing of units). We’d have a job surviving in hot weather if it wasn’t for the magnitude of latent heat.


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    Stephen Wilde

    Thanks, Phillip,

    I’ve been challenging AGW proponents on that issue on several sites and it seems that they simply did not know the significance of latent heat. So far the responses have been silence or bluster.

    If the extra IR can do anything other than accelerate evaporation and further cool the water surface then I’d like to see or hear the evidence.

    To me, it seems fatal to any permanent warming effect from extra GHGs and also destroys the so called ocean skin effect.


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    MattB

    Stephen, we did latent heat in probably year 8 or 9 science… so I really really struggle to believe that somehow the world’s leading climate scientists are unaware of latent energy, especially as it relates to evaporation from the oceans.


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    MattB

    Furthermore – such a damningly simple flaw would be easy to demonstrate in a peer-reiviewed journal of repute, save us from the folly of AGW, and earn you a Nobel prize… possibly a few!


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    Stephen Wilde

    It seems weird to me as well.

    If there were energy left over after evaporation one’s skin would not feel cool when perspiration dries, it would still heat up but at a slower rate.

    I’ve tried to find a real world example of IR warming up water in open air but all I find is examples of evaporation negating any warming. A hairdryer on bathwater comes to mind, or the uselessness of any sort of water heating device which has the source of heat outside the water.

    The only attempt I have found to deal with the problem is that ‘ocean skin’ theory but that only works by holding energy back from the air which results in cooler air and an increased sea surface /air differential which cancels the effect of warming the skin.

    If there is energy left over to go into the ocean after evaporation then how much exactly and how long would it take to warm up the entire oceanic body. It must be thousands of years but we are told it is mere decades. I cannot accept that without very clear evidence, so where is it ?


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    Stephen Wilde

    I know that the models use a broad averaged figure for evaporation from the oceans.

    I suspect that they continue to use that figure unadjusted when the extra downwelling IR from human CO2 is put into the equation. Either that or the degree of enhancement of evaporation is not accurately represented in the figures.

    In reality the latent heat from the enhanced evaporation should deal with any extra energy source that cannot penetrate the water surface (like IR).

    Why has no AGW proponent yet directed me to a simple answer? If I’m wasting my time I would like to know.


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    cmb

    Stephen Wilde:
    January 31st, 2009 at 8:17 am
    cmb

    “Air in the open as opposed to a closed environment cannot heat water.”

    – And again, what is the principle that says so? The one you quoted does not. I positively guarantee you that in any environment, open or closed, air warmer than the water can indeed heat the water. Otherwise it would not be able to cause the increased evaporation you mention in the first place.

    “I don’t see the relevance of cooking. The water in a pan is heated from conduction through the pan base by a heating element. Have you ever tried boiling a kettle with the heating element outside and above the water surface? If you tried the evaporation from the surface would cancel out all the radiative energy from the heater and the water would get no warmer.”

    – It most certainly would not. Ever use a broiler? (Here’s a quick clue-in. What is it about the radiative energy that increases evaporation?)

    The problem you are running into here is that you are attrempting to make absolute statements which simply don’t work in real life, as anyone in a kitchen with an oven can verify in 15 minutes.

    It’s interesting that CO2skeptics printed them anyway. ;)

    “You need to give me a plausible mechanism whereby radiation in the open air can heat water and it must be specifically infra red radiation which is unable to penetrate the water surface.”

    – Sure it is. http://en.wikipedia.org/wiki/Infrared_heating

    “I’ve tried to find a real world example of IR warming up water in open air but all I find is examples of evaporation negating any warming.”

    – Then go ahead and provide us with a few of those, showing no warming.


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    Rob

    “- It most certainly would not. Ever use a broiler? (Here’s a quick clue-in. What is it about the radiative energy that increases evaporation?)”

    I readily admit that I may misunderstand, but doesn’t a broiler use infrared energy to heat the food (or water)? As opposed to the element heating the air and the air then heating the water; isn’t that Stephen’s point?


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    cmb

    283Rob:
    February 3rd, 2009 at 6:36 am
    “- It most certainly would not. Ever use a broiler? (Here’s a quick clue-in. What is it about the radiative energy that increases evaporation?)”

    I readily admit that I may misunderstand, but doesn’t a broiler use infrared energy to heat the food (or water)? As opposed to the element heating the air and the air then heating the water; isn’t that Stephen’s point?”

    – Rob, Stephen is making the claim that you cannot heat water with IR energy:

    “If downwelling longwave radiation warms the water surface then any energy added to the water surface is taken away by the latent heat of evaporation.” – #272

    “If the extra IR can do anything other than accelerate evaporation and further cool the water surface then I’d like to see or hear the evidence.” – #277

    – He’s also making the claim that you cannot heat water with hot air:

    “Air in the open as opposed to a closed environment cannot heat water.” – #274

    Here he combines the two:

    “Neither air nor downwelling radiation are able to warm water because the evaporative process always uses the energy supply most readily available and if the water is warmer than the air it is taken mainly from the water and any warming effect negated.” – #272

    “Any extra energy whether from conduction or downwelling infra red radiation just increases the rate of evaporation which, because of the water’s loss of the rather large latent heat of evaporation,eliminates any warming effect from the extra energy.” – #274

    Neither claim is correct. (Same with his claim that IR cannot penetrate water – #274.) However, my simply stating that in order to save time was deemed “bad science”, so this time I am simply asking for his info.


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    Stephen Wilde

    I’d like to resolve this because it puzzles me.

    I’m talking about water in the open air where evaporation occurs readily with or without adding IR.

    I’ve read that downwelling atmospheric IR only affects the top few microns of the ocean surface. It warms the topmost molecules which promptly evaporate pulling the latent heat of evaporation from their surroundings.

    I need to know whether there is any net warming of the ocean once the evaporation induced by the IR has taken place and if so, why, given that the evaporative change of state always cools the surface from which the energy is taken.

    At the very least the removal of the latent heat of evaporation would severely deplete any warming effect from the IR and of course a windy situation would also accelerate evaporation as would a rough sea surface.


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    Stephen Wilde

    If a broiler is used to heat water the infra red heats the container then the water is heated by conduction from the container. Also the container restricts the evaporative process.


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    cmb

    Stephen Wilde:
    February 3rd, 2009 at 8:02 am
    “I’d like to resolve this because it puzzles me.

    I’m talking about water in the open air where evaporation occurs readily with or without adding IR.”

    – Then, ideally, you should make that apparent in your claims. But it doesn’t help in this situation.

    “I’ve read that downwelling atmospheric IR only affects the top few microns of the ocean surface. It warms the topmost molecules which promptly evaporate pulling the latent heat of evaporation from their surroundings.”

    – Perhaps citing your source is in order so I can see where this goes astray.

    “I need to know whether there is any net warming of the ocean once the evaporation induced by the IR has taken place and if so, why, given that the evaporative change of state always cools the surface from which the energy is taken.”

    – If you still need to know, then why publish statements that it does?

    “At the very least the removal of the latent heat of evaporation would severely deplete any warming effect from the IR”

    Here’s your problem, I think – the word “severely” is out of place when applied to an unquantified variable. Any depletion will be dependent on the temperatures, humidity, etc. etc. There’s simply no way to know offhand whether it will amount to all, or most, or much, of the IR heating. We know it can’t be all, as the ocean is indeed warming.

    My question is, why is CO2skeptics publishing statenments any cook can disprove at home? =)


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    Stephen Wilde

    Sorry, cmb, you don’t cut it.

    The Wiki entry confirms net cooling of any surface where evaporation takes place.

    I’m giving AGW proponents like you a chance to show that there is energy left over after the evaporative process so that the ocean can warm. None have succeeded so far.

    The cooking analogy is hopelessly inadequate because it involves conduction and restriction of evaporation.

    If there is no way of knowing whether the answer is all, or most, or much of the IR heating then you just destroyed AGW theory until the answer is known.

    The ocean warms either when solar input is high in relation to oceanic energy emission or when the oceans are retaning energy during a negative cycle. It need be nothing to do with IR heating.


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    Rob

    I would have to agree, in simple terms it seems readily apparent that IR radiation can and does heat water. Any resulting evaporation would depend on the temperature and humidity of the air over the water at the time.


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    Rob

    Oops, didn’t keep up, I was replying to # 284.


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    Stephen Wilde

    Rob,

    Unless air is saturated evaporation occurs all the time whether the air is warmer or colder than the water. Cold dry air is as effective as warm dry air in extracting energy from water.

    Saturation is a rare and temporary phenomenon.

    It is very easy to provoke an increase in evaporation because of the density difference between air and water.

    Any extra energy applied to a water surface will cause an increase in the rate of evaporation.

    To know whether any extra IR results in a net warming or cooling after accounting for increased evaporation is critical but no one seems to have definitive evidence. On the basis of the known science as set out in that Wiki extract a net cooling seems more likely.

    I suspect that the modellers gave an incorrect value to the influence of CO2 and that has skewed the values for all the available negative influences such as evaporation, conduction, convection and upward radiation.

    You only need to get one component wrong for all the equations to be thrown out of kilter.

    IR may heat individual water molecules but if they then break away as water vapour taking that energy with them (and more) then the remaining body of water is not likely to heat up.

    The fact is that the models are failing so something is wrong and I suspect the netted out effect of extra IR and extra evaporation.


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    Rob

    Intuitively Stephen’s premise, that the atmosphere (including the oceans) combine to create a relatively constant equilibrium temperature for a given solar output, seems logical. Provided , I would suggest, that the atmospheric gas composition stays within a reasonable range.

    It does appear from the evidence that there is no clear correlation between atmospheric gas composition (within said reasonable range) and long-term temperature patterns. Therefore, it is probable that something else is driving the long-term temperature variations. The something else most likely being the sun, as most obviously evidenced by the almost immediate temperature effect of massive volcanic activity (i.e. blocking out and/or reflecting the sun changes temperature).

    Nevertheless, it is not inconceivable that changing the atmosphere’s gas composition would have an effect and I am not yet willing to concede that increasing CO2 will, in the absence of other factors, have no climate impact at all. However, in my view, the level of changes being discussed would be most unlikely to have a significant effect (perhaps not measurable at all).


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    cmb

    Stephen Wilde:
    February 3rd, 2009 at 8:25 am
    Sorry, cmb, you don’t cut it.

    “The Wiki entry confirms net cooling of any surface where evaporation takes place.”

    – It most certainly does not. There is no way to assume net cooling of any surface just because evaporation is taking place. You are simply misreading the entry. I can easily focus a thousand watts of IR on a dark surface and drop water onto it, for instance. I guarantee that you will see evaporation AND net heating.

    Where you are going wrong is in assuming that heat of vaporization will always remove all added energy from the surface. In fact, it can only remove a certain amount.

    “I’m giving AGW proponents like you a chance to show that there is energy left over after the evaporative process so that the ocean can warm. None have succeeded so far.”

    – Sorry, it’s not my job, or anyone else’s, to correct your misunderstanding of heat of vaporization.

    “The cooking analogy is hopelessly inadequate because it involves conduction and restriction of evaporation.”

    – I have no way to suspend water in midair as if by magic. If that’s a requirement, perhaps you would prefer to examine outgassing of comets as they approach the sun? Certainly the ocean surface does not go free from conduction and restriction of evaporation! =)

    “If there is no way of knowing whether the answer is all, or most, or much of the IR heating then you just destroyed AGW theory until the answer is known.”

    – But I never made such a claim. It should be easy to obtain such answers for specific conditions, but you have not bothered to do so before publishing your guesses as if they were fact.


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    cmb

    Rob:
    February 3rd, 2009 at 2:08 pm
    “Intuitively Stephen’s premise, that the atmosphere (including the oceans) combine to create a relatively constant equilibrium temperature for a given solar output, seems logical. Provided , I would suggest, that the atmospheric gas composition stays within a reasonable range.”

    – Since the above simply refers to heat transfer equilibrium, the atmospheric composition is irrelevant to the above. Said equilibrium should be a feature of any fluidic layer, anywhere.

    “It does appear from the evidence that there is no clear correlation between atmospheric gas composition (within said reasonable range) and long-term temperature patterns.”

    – In my experience, there appears to be plenty of evidence of such a correlation, and no real evidence against it that I’ve seen. I’m definitely open to seeing some if you’ve got it.

    “Therefore, it is probable that something else is driving the long-term temperature variations. The something else most likely being the sun, as most obviously evidenced by the almost immediate temperature effect of massive volcanic activity (i.e. blocking out and/or reflecting the sun changes temperature).”

    – That’s yet another example of atmospheric composition correlating to temperature. The action of sulfate particulates, both from vulcanism and combustion, is pretty well understood. As far as the sun goes, of course it contributes to warming by supplying the initial energy. But when it comes to being responsible for the warming itself, it simply hasn’t gotten any brighter in the last 50 years – in fact, insolation is on a long term downturn.


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    Stephen Wilde

    “It most certainly does not. There is no way to assume net cooling of any surface just because evaporation is taking place. You are simply misreading the entry. I can easily focus a thousand watts of IR on a dark surface and drop water onto it, for instance. I guarantee that you will see evaporation AND net heating.”

    cmb,

    I rather assumed that any reader would realise that the initial starting point for my comments is a situation broadly similar to a little extra IR on a vast ocean surface.

    In that situation it most certainly is possible that all the extra IR energy is removed by evaporation.

    I am willing to be persuaded that some IR energy is left over but you need to specify why and how that can arise when the latent heat of evaporation is taken from the surroundings IN ADDITION TO the IR energy absorbed by a water molecule before it changes state.

    The ocean surface is not like a drop of water placed on an otherwise dry solid blackbody and that little extra IR is not like a thousnd watt blast on a drop of water. In any event it would be the dry surface that heated up and transmitted energy by conduction to the drop of water not direct heating by the IR. The water droplet would evaporate too fast for it to warm up from the incoming IR alone.

    If one were to submerge that blackbody surface in plenty of water then the water would stop ANY of the IR from warming up that surface and the water molecules at the surface would evaporate fast enough to stop the main body of water warming up at all.


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    cmb

    Stephen Wilde:
    February 4th, 2009 at 2:35 am
    “It most certainly does not. There is no way to assume net cooling of any surface just because evaporation is taking place. You are simply misreading the entry. I can easily focus a thousand watts of IR on a dark surface and drop water onto it, for instance. I guarantee that you will see evaporation AND net heating.”

    cmb,

    I rather assumed that any reader would realise that the initial starting point for my comments is a situation broadly similar to a little extra IR on a vast ocean surface.

    In that situation it most certainly is possible that all the extra IR energy is removed by evaporation.”

    – But you claim that is a fact under all circumstances. If that’s not what you mean, you have a bit of rewriting to do.

    I am willing to be persuaded that some IR energy is left over but you need to specify why and how that can arise when the latent heat of evaporation is taken from the surroundings IN ADDITION TO the IR energy absorbed by a water molecule before it changes state.

    – Certainly. That can arise when the heat of evaporation removed is insufficient to compensate for all IR heating. Since IR penetrates water, and only surface molecules can evaporate at the temps we’re discussing, that’s most of the time.

    In any case, you are the one making the claims and it is up to you to defend them. So far you have not produced a single bit of evidence from anywhere that supports your specific claims.


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    Stephen Wilde

    Try this:

    http://eesc.columbia.edu/courses/ees/climate/lectures/o_atm.html

    Extracts:

    “net long wave back radiation cools the ocean; heat transfer by conduction and convection between the air and water generally cools the ocean as does evaporation of water from the ocean surface.”

    “Net back radiation cools the ocean, on a global average by 66 watts per square meter.”

    “Latent Heat: The largest heat loss for the ocean is due to evaporation, which links heat exchange with hydrological cycle (Fig. 4). On global average the heat loss by evaporation is 78 watts per square meter. Why so large? Its because of the large heat of vaporization (or latent heat) of water, a product of the polar bonding of the H2O molecule, as discussed in the Ocean Stratification lecture. Approximately 570 calories (2.45 x 106 joules) are needed to evaporate one gram (kilogram) of water! A gram of water is roughly one cubic centimeter, amounts to a loss of one centimeter of water per a square centimeter of ocean surface area. The water vapor leaving the ocean is transferred by the atmosphere eventually condensing into water droplets forming clouds, releasing its latent heat of vaporization in the atmosphere, usually quite remote from the site of the evaporation, thus representing a significant form of heat transfer, latent heat transfer.”

    There is a nice discussion of the subject here:

    http://www.warwickhughes.com/blog/?p=28

    Especially the comments of Douglas Hoyt.


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    Stephen Wilde

    To save time for readers this is what Mr. Hoyt says:

    “The absorption coefficient for liquid water as a function of wavelength is given at http://www.lsbu.ac.uk/water/vibrat.html (see the figure near the end). Thermal infrared in the Earth’s atmosphere is around 10 to 20 microns where the absorption coeficient (A) is about 1000 cm-1. The transmission in liquid water (T) equal exp(-A*L) where L is the depth of penetration. For the case where 1/e of 27% of the incident photons remain unabsorbed, with A=1000 cm-1, the L= 1/1000 cm = 1/100 mm. 98% of the incident photons will be absorbed within 3 times this distance. So one can see from the figure, than practically no infrared photons penetrate beyond 3/100 mm. When I said all the photons are absorbed in the top millimeter of the water, I was being very generous. A more precise estimate of A is 5000 cm-1 at 15 microns where carbon dioxide is emitting radiation, so even 0.03 mm is extremely generous. Since the liquid water is such an effective absorber, it is a very effective emitter as well. The water will not heat up, it will just redirect the energy back up to the atmosphere much like a mirror. The only way to explain the ocean heating in depth is for the solar radiation to change and I have already pointed out that decreasing clouds, as measured by ISCCP, indicate increasing solar radiation is occurring right where the ocean heating is reported to be occurring.”


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    Phillip Bratby

    Stephen: Good stuff there. Hopefully cmb will give up (unless he can’t understand, or won’t accept, basic physics).


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    cmb

    I’m quite willing to give up, Phil. It’s fine with me if denialist papers contain statements that any housekeeper would laugh at. If Stephen is willing to use comments to single-issue denialist websites as sources, I doubt he’s going to like mine.

    http://www.sciencemag.org/cgi/content/abstract/265/5169/224

    The Role of the Tropical Super Greenhouse Effect in Heating the Ocean Surface
    Dan Lubin 1
    1 California Space Institute and Center for Clouds, Chemistry, and Climate, University of California, San Diego, La Jolla, CA 92093-0221, USA.

    “Measurements made by a Fourier transform infrared (FTIR) spectroradiometer operating in the middle infrared (5 to 20 micrometers, with a spectral resolution of one inverse centimeter) imply that there is an anomalously large greenhouse effect over equatorial oceans that is caused by water vapor. As sea-surface temperature increased from 297 to 303 degrees kelvin, the net infrared cooling at the surface decreased by 30 to 50 watts per square meter. Thus, according to the FTIR data, the super greenhouse effect that had been inferred from satellite measurements contributes directly to radiative heating of the sea surface. The data demonstrate that most of this heating occurs in the middle infrared by means of the continuum emission window of water vapor and that tropical deep convection contributes substantially to this super greenhouse effect.”

    http://oceanworld.tamu.edu/resources/ocng_textbook/chapter05/chapter05_06.htm

    “What then warms the atmosphere and drives the atmospheric circulation shown in Figure 4.3? The answer is rain and infrared radiation from the ocean absorbed by the moist tropical atmosphere. Here’s what happens. Sunlight warms the tropical oceans which must evaporate water to keep from warming up. The ocean also radiates heat to the atmosphere, but the net radiation term is smaller than the evaporative term. Trade-winds carry the heat in the form of water vapor to the tropical convergence zone where it falls as rain. Rain releases the latent heat evaporated from the sea, and it heats the air in cumulus rain clouds by as much as 500 W/m2 averaged over a year (See Figure 14.1).”

    As we see, not only does IR penetrate seawater (Stephen had specifically claimed otherwise), but in fact its rapid absorption and the evaporation it triggers are an important part of heating the atmosphere. How this becomes a problem for AGW theory, then, is a bit of a mystery.

    It might be interesting to take a section of ocean surface .03 millimeters deep (to generously use Hoyt’s figure, which is actually for the wrong wavelenths if we are discussing CO2 – judging by the graph he cites, it looks like his absorption coefficient is off by a factor of around ten times) and calculate what percentage of those molecules are actually on the surface and able to evaporate. I think some here might find that answer a bit of a surprise, but the math itself is beyond me personally. Any takers?


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    Stephen Wilde

    “Sunlight warms the tropical oceans which must evaporate water to keep from warming up. The ocean also radiates heat to the atmosphere, but the net radiation term is smaller than the evaporative term.”

    TO KEEP FROM WARMING UP


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    Stephen Wilde

    It is the re radiated IR that is too long a wavelength to penetrate water. Insteads it warms the topmost molecules, increases evaporation and gets carried away by wind and convection.

    There cannot be a new equilibrium set by such IR because it never gets the chance to warm the main body of the ocean. The weather systems adjust instead to whisk it away to space and maintain both the sea surface/surface air equilibrium AND the energy in from the sun/radiation to space equilibrium.

    Heating the atmosphere is insufficient. To change the equilibrium of the whole system you have to heat the main body of the oceans. Downwelling longwave IR cannot do it.


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    michael

    Gentlemen; I cannot believe I am reading this debate. You are turing elementary basic physics into a massive complex charade. The physics is so basic and so well understood no references are necessary – look in any physics text book if you doubt me. The situation is as follows;

    1) water strongly absorbs infrared thus the infrared energy striking the surface will be rapidly absorbed
    2) this energy is converted to heat and will warm the water surface
    3) the heat will spread through the water by mixing processes such as waves and to some extent by conduction.

    this is the energy input side and there is no doubt of the above whatsoever. If you feel you need proof, meaure the temperature of an open swimming pool in the morning of a hot summers day and again in the evening. The temperaturein the evening is higher. If it did not come from energy absorbed from the sun, where pray tell did it come from?

    However, this is only half of the issue. The other half is evaporation of water. Evaporating water takes energy – lots of energy in fact around 2300 joules per gram evaporated. This energy typically comes from the bulk of the water. Don’t believe me? wet your hand and then place it is a blast of hot air (a hand drying found in many public toilets will do). Does the air feel hot or cold? Now let your hand dry, and put it in the air stream again. Does the air now feel hot or cold? Don’t take my word for it – GO AND TRY IT.

    So evaporation cools the water, radiation from the sun warms it. Which dominates? Well, what would happen if the energy from the sun was not there? Would evaporation still occur and to the same extent? If you argue yes then in the absence of solar energy the water would have cooled and the presence of solar energy at least reduces that cooling. If you answer no then ask what is there about the solar input that caused more evaporation? The answer is obvious, it made the water warmer and warmer water encourages increased evaporation. But evaporation cools the water. Could it cool it below where it started? If it did that the increased evaporation would stop since it was the higher temperature that caused it in the first place.

    The answer is obvious. Incoming solar radiation warms the water which results in increased evaporation. This evaporation reduces the temperature increase. The magnitude of the evaporative factor depends on other conditions. If it is windy and the air is of low humidity evaporation will be significant and the temperature rise will be small. If it is still and the air is already very humid the evaporative effect will be small and the temperature rise greater.

    Go look again at a swimming pool on a hot day in summer. The pool loses lots of water to evaporation – think of how often it needs to be refilled yet despite that the water is warmer in the evening than in the morning.


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    Stephen Wilde

    Fair point but there is a flaw.

    The warming of the pool is a result of conduction from the land around it, not from radiation entering it from the air. That radiation to the water surface is what causes the evaporation. The predominance of the surrounding land causes warming to gain the advantage.

    The surface of the Earth is 70% water and only 30% land. Cooling from evaporation has the advantage over conduction from the land.

    Apart from that your summary is correct but you missed the crucial point.


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    Stephen Wilde

    In the absence of the sun, evaporation and cooling will continue but the latent heat of evaporation is taken from air and water in proportions that move both towards equilibrium.

    Water both cools warmer air and warms cooler air and the source of the latent heat of evaporation is the mechanism that drives water and air towards equilibrium with or without an input from the air or the sun.


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    Rob

    Michael,

    From what I’ve read I don’t think there’s any doubt that direct solar radiation warms the oceans; in fact it penetrates quite a distance into the water. The debate going on here (I think) is whether changing the green house gas composition of the atmosphere will result in additional warming through indirect radiation from the atmosphere.

    Then again, I may have missed the point entirely ;-)


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    Stephen Wilde

    Rob,

    That is correct. Solar radiation being mostly energetic shortwave penetrates deeply enough to set the prevailing ocean temperature at any point in time.

    Downwelling radiation from GHGs is weak longwave and affects only the very topmost molecules of the ocean surface. Because it’s effect is only on those surface molecules it provokes extra evaporation which takes the extra IR back into the air and additionally cools the ocean surface by loss of the latent heat of evaporation thus maintaining or possibly accelerating the ocean/air energy flow.

    Thus some of the warming of the pool could be down to shortwave solar insolation but in fact in a body of water as small as such a pool the shortwave input is likely to be removed by evaporatrion as well leaving the primary influence as conduction from the surrounding ground.

    In fact even that conduction would be partly neutralised by evaporation which is why the pool water never gets as warm as the ground around it.

    Overall the variability of evaporation is a hugely underestimated phenomenon and is not accurately reflected in any climate models.

    For example I am not aware of any climate model that accommodates the effect of increased evaporation caused by the conduction of energy from land into continental shelves.

    The inadequacy of current modelling is mind boggling when one gets into the detail.

    It is all basic physics and hardly justifies peer review.


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    michael

    Stephen; I am highly skeptical of AGW as my earlier posts show but I will not shy away from the science. If you really think a pool heats from the ground and not from the sun I invite you to do a very simply experiment (although it does take a bit of work). Find a pool, wait dig a hole say 300 mm deep or better find a thermometer on a long stick and push it into the groud about 300 mm. Wait for a warm day and measure the temperature at the end of the day. Then measure the water temperature. Then remember heat froms from hot to cold not vice versa.

    Its always better if you do the experiment yourself but just in case, I have done this and can tell you the outcome. The ground even a foot down changes temperature remarkably little – hovers around 14C. The pool water easily can get to 30C. Also water is a poor conductor of heat yet the middle of the pool (farthest from the edges) gets just as warm as the edges. Evwen further, if conduction from the rgound was the cause one would expect that the water would get warmer as one goes below the surface since there is no evaporative loss down there yet the surface water is the warmest and it gets colder as one goes lower into the water.


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    Stephen Wilde

    A problem of wording.

    I did acknowledge the warming effect of shortwave from the sun and in my enthusiasm overstated the immediate effect of evaporation. My point should have been that the longwave IR would be removed by evaporation because it cannot penetrate the surface and the general warming from the shortwave solar input would help to accelerate the rate of evaporation.

    As for the ground I meant that there is a contribution from the surrounding ground surfaces being heated by the sun. I am aware that deeper down the ground is at a stable 14C or thereabouts.

    I’m sceptical about the whole pool getting to 30C but if it does then that would be from solar shortwave and conduction, not downwelling longwave whether it be natural or human sourced.


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    Stephen Wilde

    One should also consider the absence of the solar shortwave whether at night time or if the sky clouds over. The pool water will cool rapidly due to the latent heat of evaporation being taken primarily from the water when the air is cooler.

    If the air temperature goes below 14C then conduction from the surrounding ground becomes relevant in keeping the main body of the pool liquid even if the surface freezes.


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    Michael

    Thought I would throw something of interest into the debate. I mentioned in earlier posts I was preparing an article on the K&T model. Here is a portion of it, for those interested.

    AN ANALYSIS OF THE KIEHL AND TRENBERTH MODEL

    The global circulation models (GCM’s), used to predict global warming, are based on the Kiehl and Trenberth model of Earth’s annual global mean energy flow budget.

    This model is documented at;

    http://www.cgd.ucar.edu/cas/abstracts/files/kevin1997_1.html
    (from Bull Amer. Meteor Soc, 78, 197-208 1997).

    There is an update dated 2008 at;

    chrisclose.wordpress.com/2008/12/10/an-update-to-Kiehl-and-trenberth-1997/

    although the numbers are only slightly changed. The K&T model (2008 update) specifies the following energy flows all with the units watts/m2.

    Incoming solar radiation 341
    Reflected solar radiation 102
    Energy radiated from earth’s surface 396
    Energy absorbed by the atmosphere 356
    Energy radiated from surface directly to space 40
    Energy emitted by atmosphere to space 169
    Energy emitted from clouds to space 30
    Energy transported to atmosphere via
    Convection and latent heat of water vapour 97
    Solar radiation directly absorbed by atmosphere 78

    This data shows that energy input to the atmosphere via radiative processes = 356 + 78 = 434 watts/m2. Energy input via convective processes = 97 watts/m2. Thus energy input to the atmosphere is dominated by radiative processes (82% radiative and 18% convective).

    It should also be noted that the global circulation models GCM’s use a concept called the equivalent radiation altitude. This is a hypothetical altitude from which it is assumed long wave radiation back out to space emanates. Changes in greenhouse gas concentrations are assumed to change the equivalent radiation altitude. Changes to this equivalent radiation altitude together with the known lapse rate through the atmosphere are used to calculate changes in surface temperatures.

    Now consider the well known and documented temperature versus altitude data (lapse rate) for Earth’s atmosphere. This temperature profile is established and maintained by the need for energy balance at every altitude.

    The lapse rate consists of an almost linear decrease in temperature with altitude from the surface (+14C) to the top of the troposphere – the tropopause (at between 10 – 14 km altitude) where the temperature is between about -60 and -80 C depending on latitude. Above the tropopause (in the stratosphere) the temperature rises, again almost linearly, to a maximum of between -30C and +20C at an altitude of about 50 km.

    The tropopause is thus a cold region sandwiched between warmer regions above and below. For this situation to be stable (and it is stable), the tropopause must have a way of losing energy to a colder sink – otherwise it would warm up due to energy input from the adjacent regions. The only colder region available is space itself and the only energy transfer mechanism available is radiative loss.

    Thermal emissions from the tropopause will all be in the 8 micron to 50 micron wavelength range (governed by the temperature of the emitter) and can only occur at the characteristic absorption/emission lines of the green house gases. There is however a problem with this scenario. Ten percent of Earth’s atmosphere is above the tropopause in the stratosphere and the greenhouse gases in this region would normally absorb the emissions from the tropopause. Further, since the air in the stratosphere is warmer, the downwards radiation onto the tropopause would exceed the upwards radiation from it leading to net energy gain not loss. Yet the tropopause is colder than the stratosphere so it must have a mechanism for losing energy.

    There would appear to be only one solution to this apparent paradox and that is that there is an abrupt change in the greenhouse gas composition at the tropopause such that the tropopause can radiate at wavelengths which the stratosphere is not capable of absorbing. The tropopause represents a temperature inversion which greatly inhibits convection and when that is coupled with the fact that water vapour is carried up from Earth’s surface principally by convection, one would immediately suspect water vapour as the variable component – high concentration in the troposphere and low concentration in the stratosphere. In fact that is confirmed by the two quotes taken from the following link;

    http://www.metoffice.gov.uk/education/secondary/teachers/atmosphere.html

    “The atmosphere is well mixed below 100 km, and apart from its highly variable water vapour and ozone contents, its composition is as shown below”

    “As well as a noticeable change in temperature, the move from the troposphere into the stratosphere is also marked by an abrupt change in the concentrations of the variable trace constituents. Water vapour decreases sharply, whilst ozone concentrations increase. These strong contrasts in concentrations are a reflection of little mixing between the moist, ozone-poor troposphere and the dry, ozone-rich stratosphere.”

    This information explains how the tropopause can remain colder than the air above and below. It also explains why temperature rises in the stratosphere. Ozone is a strong absorber of ultraviolet energy from the sun and such absorption will warm the stratosphere. The energy gained will be re-emitted as thermal infrared energy at the absorption/emission lines of the greenhouse gases present, mainly CO2 and methane. The energy absorption by ozone is greatest at around 50 km altitude which is why the temperature peaks at this point and the temperature profile down to the tropopause is more or less an upside down version of what happens in the troposphere.

    It should be noted that the tropopause of course radiates at all wavelengths corresponding to greenhouse gas absorption/emission lines but those greenhouse gases present in the stratosphere also radiate back down onto the tropopause and since they are warmer, the downward radiation exceeds the upwards radiation. Thus the only net energy loss from the tropopause occurs at the wavelengths corresponding the water vapour absorption/emission lines.

    Since the tropopause can radiate relatively strongly at the water vapour absorption/emission lines (strongly enough to keep itself cold) it follows that the emissivity at these lines must be relatively high which also means that the absorptivity is also high for the reasons discussed at the start of this paper (omitted here). Couple that with the fact that water vapour concentration is higher at lower altitudes and it follows that the tropopause (possibly together with a small region immediately below it) will be opaque to radiation at the water vapour absorption/emission lines. That means that emission from lower in the atmosphere directly to space becomes impossible at the water vapour absorption/emission lines because the energy is re-absorbed by the region immediately below the tropopause.

    The implication is that thermal energy from the surface can only escape to space in two ways. Firstly by surface emission escaping directly to space, this would be at wavelengths which the greenhouse gases do not absorb. Secondly by emission from the tropopause at the wavelengths corresponding to the water vapour absorption/emission lines.

    The above understanding can also help to gain at least some idea of the relative magnitude of the two emission mechanisms.

    A stated earlier, ozone is a very good absorber of ultraviolet radiation from which it follows that it will absorb most of it (there are some wavelengths which ozone does not absorb which is why one can get sunburnt). The sun provides on average 340 watts/m2 at the top of the atmosphere. According to

    http://www.easthorse.net/cm/images/spectrum.gif

    this is distributed as about 5% in the ultraviolet
    46% in the visible
    49% in the near infrared up to 2.5 microns

    This equates to about 17 watts/m2 of ultraviolet. Since the ozone absorption of ultraviolet is at 50 km elevation this is likely to be above most of the albedo effects so most of that 17 watts/m2 will be absorbed by ozone and re-emitted as long wave radiation at the CO2 and methane absorption/emission lines. The remaining incoming solar energy is either reflected back out to space by Earth’s albedo or is absorbed lower in the atmosphere or at the surface.

    The overall albedo of Earth is 0.3 so 340 * 0.3 = 102 watts/m2 is reflected back to space leaving 340 – 102 – 17 = 221 watts/m2 to be absorbed at or below the tropopause. All of this must be radiated back out to space as long wavelength radiation if thermal balance is to be maintained.

    Now assume the absorption/emission lines of water vapour cover X per unit of the total emission spectrum. That would mean the emission from the tropopause would be the black body radiation (as calculated by Stefan’s law) * X. Again since absorption and emission are reciprocal processes, water vapour lines will absorb X of the black body emission from the surface leaving (1-X) to be radiated away. For Earth’s surface however we need to also add the absorption by the other greenhouse gas components. Water vapour is normally specified as contributing between about 50% and 75% of the total greenhouse effect which means the fraction free to radiate back out to space is somewhere between about (1-X/0.5) (water vapour is 50% of total greenhouse effect) and (1-X/0.75) (water is 75% of total greenhouse effect)

    Using Stefan’s law, for a surface temperature of 288 the black body radiation is 390 watts/m2 and for the tropopause at -60C (213K) the black body radiation is 117 watts/m2

    In order to achieve energy balance the total emission must equal 221 watts/sq M hence;

    390*(1-X/0.5) + 117X = 221 for water being 50%of greenhouse effect
    From which it follows X = 0.255
    Or

    390(1-X/0.75) + 117X = 221 water vapour is 75% of greenhouse effect
    From which it follows X = 0.42

    This suggests surface emission to space is between 390*(1-.255/.5) = 191 watts/m2 and 390 *( 1-0.42/0.75) =172 watts/m2 and therefore emission from the tropopause is between 221 – 191 = 30 watts/m2 and 221 – 172 = 49 watts/m2.

    This result suggests almost all the radiation to space is from the surface, very little from the atmosphere which is the reverse of the K&T model. Is such a result possible? Wikipedia ( http://en.wikipedia.org/wiki/Atmospheric_windows ) cite a reference from J.T. Houghton transcribed below

    The atmospheric window refers to those parts of the electromagnetic spectrum that are, with the earth’s atmosphere in its natural state, not absorbed at all. One atmospheric window lies approximately at wavelengths of infrared radiation between 8 and 13 or 14 micrometres[1].

    [1] ISBN 0521339561 Houghton, J.T. The Physics of Atmospheres

    Integrating Plank’s distribution curve from 8 to 14 microns for a temperature of 288K yields a total of 164 watts/m2. The wavelength range above 14 microns contains many lines but there are also gaps between the lines which allow radiation to space. If these contribute just 8 watts/m2 the total is within the window calculated here.

    IMPLICATIONS OF THIS ANALYSIS FOR THE KIEHL TRENBERTH MODEL

    The first outcome of the above analysis is that the concept of an equivalent emission altitude with a constant lapse rate as used by global circulation models has little meaning. The analysis suggests that energy loss to space from Earth’s surface can only occur directly from the surface or from the tropopause although the relative magnitude of each could change with changing greenhouse gas concentrations. Such change in relative emissions would also have to be reflected in a change in the tropopause temperature and a change to the lapse rate.

    The analysis further suggests that the green house gas concentrations in the atmosphere are so high that they block essentially all the radiation emitted by Earth’s surface at their absorption lines. There is still energy at these absorption lines emitted to space but for the well mixed greenhouse gases such as CO2 and CH4 this energy comes from UV absorption of incoming solar radiation by ozone in the stratosphere. In the case of water vapour, the energy comes from near infrared absorption of incoming solar radiation by water vapour at or just below the tropopause.

    The very large difference in surface versus atmospheric emission levels predicted from this analysis compared to the Kiehl Trenberth model seriously questions the basis of global circulation models based on that K&T data. It also calls into question the reliability of the output from such models and in the predictions flowing from those models.


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    Stephen Wilde

    I’m quite sure that models don’t have the mechanics of the whole system right and that post is a useful approach to try and work out why/how.

    I’m concentrating on the logical conceptual overview rather than the mathematical aspects since the maths is beyond my expertise.

    Mind you I think it is beyond the expertise of a lot of contributors to the debate whether they be professional scientists or not. The problem with climatology is that it is not a discrete discipline in itself so a lot of scientists on the periphery think they know more than they do.


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    Michael,
    Your posts are very impressive – you clearly know what you are talking about. you really ought to set up your own blog or website.


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    cmb

    308Stephen Wilde:
    February 5th, 2009 at 8:59 am

    “Overall the variability of evaporation is a hugely underestimated phenomenon and is not accurately reflected in any climate models.”

    – If so, that may be because in our closed hydrological cycle, all energy taken up by heat of vaporization is always redeposited when precipitation occurs later. In short, the cooling you speak of simply results in heating elsewhere, to the exact same degree.

    “For example I am not aware of any climate model that accommodates the effect of increased evaporation caused by the conduction of energy from land into continental shelves.”

    – I know of no such effect, or of such a conduction of energy. Do you have any sources out there I could read on these? I remain skeptical. After all, the ocean is a fluid bed, and rock is a great insulator. Considering the distances involved, both horizontal and vertical, I suspect lateral transfer of solar heating through geological formations to the ocean is negligible in the extreme, so negligible as to be undetectable.


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    cmb

    314PaulM:
    February 6th, 2009 at 2:02 am
    “Michael,
    Your posts are very impressive – you clearly know what you are talking about. you really ought to set up your own blog or website.”

    – I agree, Michael. Certainly you have enough going on there that I’ll never have the time to analyze it properly. I do have a couple of hastily-formed questions.

    First, just out of curiosity, why do we think all GCMs are based on Kiehl-Trenberth? I missed that part.

    Also, and this may be a stupid question, but with the 8-14um band riddled with water vapor absorption lines, and impinging on a CO2 peak, is it really wise to consider it a ‘transparent’ enough window to use Planck’s curve as a stand-in for computing power?

    Apologies if I’ve misunderstood your work, but J. T. Houghton’s idea that nothing at all is absorbed in that window strikes me as odd.

    Water vapor window diagram here:

    http://en.wikipedia.org/wiki/File:Atmosfaerisk_spredning.gif

    That certainly looks a lot rougher than a blackbody curve to me.


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    Stephen Wilde

    The latent heat of evaporation is deposited higher up in the air by condensation and so is accelerated to space. It does not come back down with rainfall.

    If there is no energy transport from land to oceans then that is fine by me. It just serves to illustrate the inadequacy of the pool analogy and removes one possible complication from my contention that the sea drives the air temperatures and cannot be affected by warmer air, downwelling longwave or, it seems, leakage from the solar heated land masses.


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    cmb

    317Stephen Wilde:
    February 6th, 2009 at 3:55 am
    “The latent heat of evaporation is deposited higher up in the air by condensation and so is accelerated to space. It does not come back down with rainfall.”

    – In fact, the heat comes back wherever water chooses to condense, from blades of grass to pitchers of lemonade. In any case, it comes out below the tropopause and so is still hampered on its way to space by GHG absorption, including other water vapor. So no points for that one.

    “If there is no energy transport from land to oceans then that is fine by me. It just serves to illustrate the inadequacy of the pool analogy”

    – Nope. In fact, it eliminates your problem with the pool analogy. You just tried to pass off the pool heating as transmitted from land, remember? Here you are:

    [Stephen Wilde:
    February 5th, 2009 at 8:06 am
    Fair point but there is a flaw.

    The warming of the pool is a result of conduction from the land around it, not from radiation entering it from the air. That radiation to the water surface is what causes the evaporation. The predominance of the surrounding land causes warming to gain the advantage.]

    So I’m afraid I’m going to have to bust you on that fib. Sorry.

    “and removes one possible complication from my contention that the sea drives the air temperatures and cannot be affected by warmer air, downwelling longwave or, it seems, leakage from the solar heated land masses.”

    – If you want to stick to an obvious invention of the imagination in the face of conflicting evidence, feel free. I have already cited sources which knock it out.


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    Stephen Wilde

    1) You left out my subsequent clarification:

    “A problem of wording.

    I did acknowledge the warming effect of shortwave from the sun and in my enthusiasm overstated the immediate effect of evaporation. My point should have been that the longwave IR would be removed by evaporation because it cannot penetrate the surface and the general warming from the shortwave solar input would help to accelerate the rate of evaporation.

    As for the ground I meant that there is a contribution from the surrounding ground surfaces being heated by the sun. I am aware that deeper down the ground is at a stable 14C or thereabouts.”

    2) Dew on grass is nothing compared to the rest of the hydrological process.The latent heat of evaporation gets accelerated to space.

    3) “The surface of the Earth is 70% water and only 30% land. Cooling from evaporation has the advantage over conduction from the land.”

    The above words by me recognise that the land does not contribute enough energy to the oceans to offset the cooling effect of evaporation on the oceans.

    Your selective quotations are designed to mislead and confuse.


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    cmb

    Stephen Wilde:
    February 6th, 2009 at 4:52 am
    1) You left out my subsequent clarification:

    “A problem of wording.

    I did acknowledge the warming effect of shortwave from the sun and in my enthusiasm overstated the immediate effect of evaporation. My point should have been that the longwave IR would be removed by evaporation because it cannot penetrate the surface”

    – still completely false.

    “and the general warming from the shortwave solar input would help to accelerate the rate of evaporation.”

    – And the warming from IR input as well.

    As for the ground I meant that there is a contribution from the surrounding ground surfaces being heated by the sun. I am aware that deeper down the ground is at a stable 14C or thereabouts.”

    – Still a vanishingly small contribution compared to solar heating of the water. Not even worth mentioning.

    “2) Dew on grass is nothing compared to the rest of the hydrological process.The latent heat of evaporation gets accelerated to space.”

    – Actually, it just gets deposited wherever there’s water vapor, and still must make it to space through the entire stratosphere, and that dreaded infrared band saturation. =)

    “3) “The surface of the Earth is 70% water and only 30% land. Cooling from evaporation has the advantage over conduction from the land.”

    The above words by me recognise that the land does not contribute enough energy to the oceans to offset the cooling effect of evaporation on the oceans.”

    – That was never in question for a moment.

    “Your selective quotations are designed to mislead and confuse.”

    – A blatant lie on your part, Stephen. That ends our conversation.


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    cmb

    Additional question for Michael, this one almost certainly due to a lack of knowledge on my part. You state, at various points:

    “Thermal emissions from the tropopause will all be in the 8 micron to 50 micron wavelength range (governed by the temperature of the emitter) and can only occur at the characteristic absorption/emission lines of the green house gases.”

    “It should be noted that the tropopause of course radiates at all wavelengths corresponding to greenhouse gas absorption/emission lines”

    “Ozone is a strong absorber of ultraviolet energy from the sun and such absorption will warm the stratosphere. The energy gained will be re-emitted as thermal infrared energy at the absorption/emission lines of the greenhouse gases present, mainly CO2 and methane.”

    My question, then, is, why do we think that thermal emissions from the tropopause can only occur at the characteristic absorption/emission lines of the green house gases?


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    michael

    cmb; you ask valid questions. Its easy when posting on a blog site to assume too much. I will try and explain.

    If a substance is to radiate energy it must have within its structure some sort of resonator. It’s probably easier to understand by analogy so lets think of a piano string. If the piano string is plucked it can radiate sound energy to the air but only at the frequency of the string. Of course the string might have more than 1 mode of vibration and each mode may resonate at a different frequency. If so it has the capacity to radiate sound energy at all the modes. It does not however have the ability to radiate energy at frequencies at which there is no resonance. Thus a string tuned to middle C can’t radiate sound at say A.

    The same thing applies for electromagnetic emission by a gas molecule. If there are bonds within the modelcue that can resonate, the molecule becomes able to emit electromagnetic energy at a wavelengths corresponding to the vibrational resonances but only at those wavelengths. Thus CO2 and H2O have such resonance bonds and can emit at the characteristics wavelengths corresponding to those resonances. Nitrogen and oxygen do not and therefore can’t radiate ie: are not greenhouse gases.

    To forstall the question how come the ground can radiate at all wavelengths. The reason here is that for a solid the atoms are really close together and each molecule interats with its neighbours to such a degree that the resonances all smear out to an almost continuous bands. That is not the case in a gas.

    Now its one thing to say the molecule can radiate at some wavelengths but its quite another to be able to say it does radiate. Our piano string has the capacity to radiate sound at middle C but if it is to actually do so it has to be plucked. What plucks the resonances in our greenhouse gas molecules. The answer is temperature. Temperature is really just a measure fo the average energy of the molecules. The relationship between temperature and the ability of a molecule to emit is given by Panks distribution curve. This curve drawn for a specific temperature specifies the MAXIMUM energy that can be radiated at each wavelength – by a perfect radiator called a black body. Thus for example ozone has resonances at around 0.2 microns but it does not radiate at these wavelengths in the atmosphere simply because it is not hot enough. To be able to excite this resonance the temperature would have to be thousands of degrees.

    Does it mean that if there is a resonance and Planks distribution curve shows a certain maximum emission at that wavelength for the given temperature then the molecules emit at this intensity? NO. The actual amount of emission depends on the strength of the resonator. Plank’s curve only specifies the maximum possible. The difference between the two is called the emissivity factor. This is why a polished silvery metal surface is a poor emitter whereas a dull black surface is a good emitter.

    This is probably enough for one post and anyway I am running out of time. Hope it heps a bit.


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    michael

    forgot your other question about the 8-14 micron band riddled with water vapour and CO2 lines. The simple answer is that it is not.Water vapour has many bands below 8 and above 13-14 microns. CO2 has major absorption peaks at 2.7 microns 4.3 microns (don’t quote me exactly on this number I am working from memory) and at 15 microns. It does not have any absorbances between 8-14. The lack of any absorption bands is why its called the atmospheric window. I gave the address of the Wikipedia reprint of this quote (from physics of atmospheres) where you can check this. On either side of this band there are numerous absorption peaks – the picket fence people talk about. Some energy can still radiate but much is blocked.


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    cmb

    Thanks, Michael, I’ll respond to both of these in the same post.

    michael:
    February 6th, 2009 at 1:10 pm
    “forgot your other question about the 8-14 micron band riddled with water vapour and CO2 lines. The simple answer is that it is not.Water vapour has many bands below 8 and above 13-14 microns. CO2 has major absorption peaks at 2.7 microns 4.3 microns (don’t quote me exactly on this number I am working from memory) and at 15 microns. It does not have any absorbances between 8-14.”

    – I’m going to have to respectfully disagree. Both CO2 and H2O obviously absorb some light within this window. From your own source:

    http://en.wikipedia.org/wiki/File:Atmosfaerisk_spredning.gif

    Note H20 and CO2 lines denoted by arrows below the graph. Hence, it appears that using the planck curve as a stand-in for this curve is inappropriate and will skew your results.

    ———————————-

    “The same thing applies for electromagnetic emission by a gas molecule. If there are bonds within the modelcue that can resonate, the molecule becomes able to emit electromagnetic energy at a wavelengths corresponding to the vibrational resonances but only at those wavelengths. Thus CO2 and H2O have such resonance bonds and can emit at the characteristics wavelengths corresponding to those resonances. Nitrogen and oxygen do not and therefore can’t radiate ie: are not greenhouse gases.”

    – But they can and do still radiate normal thermal radiation, the wavelengths of which are a probability distribution depending on temperature and not limited to emission lines.

    http://en.wikipedia.org/wiki/Thermal_radiation

    Hence, it would appear that limiting energy transfer from a body of gas to GHG emission lines and ignoring other wavelengths would artificially understate its radiative cooling potential by a large degree. I would be interested in any detailed exposition that shows this limitation is correct.

    How does your math turn out if you use the actual absorption spectrum for the atmospheric window instead of the Planck curve, and actual total radiation from the tropopause?

    To be clear, I’ll cut and paste:

    “Now assume the absorption/emission lines of water vapour cover X per unit of the total emission spectrum. That would mean the emission from the tropopause would be the black body radiation (as calculated by Stefan’s law) * X. ”

    I would be interested to see examples of this technique used elsewhere. Right now, I think I have to contend that X is unnecessary when calculating the total emission.


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    Phillip Bratby

    The absorption bands can be found at:

    http://brneurosci.org/co2.html


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    Michael

    Hello CMB; I am sorry but you have misunderstood what I have been trying to explain. The emission at the resonance lines is not in addition to thermal emission it IS thermal emission. I mentioned that for solids the atoms are so close together than the lines are broadened into bands and these may well allow continuous absorption and emission across almost the entire spectrum – which is sort of the definition of a black body (technically a black body has an emissivity of 1 at all wavelengths). I also mentioned that this does not apply to gases. Does this mean that I am saying oxygen and nitrogen do not have any thermal emissions? YES that is what I am saying at least at room temperatures. There may be resonance bands at higher energy which can only be excited at much higher temperatures. In fact I know that to be the case because at about 5000K nitrogen glows a pale pink and air glows a pale green. I know because I have done exactly that in connection with one of the research projects I was running.

    All this probably sounds hard to believe and counter intuitive. It is. To give a bit of history. Many many years ago physicists were trying to understand radiation from heated sources and they applied classical physics. Classical physics gave spectacularly the wrong answer – infact it predicted infinite emission which clearly is not the case. For many years this topic was unsolved and not understood. It was finally solved by quantum mechanics, in fact this very issue was one of the early spectacular successes of quantum mechanics which is why Max Plank got his name on the energy distribution relationship he derived. The BIG difference between classical physics and quantum mechanics for a lay person is that classical phyisics is intuitive whereas quantum mechanics is most decidedly not. Thats why so many people have trouble understanding quantum mechanics.


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    cmb

    Michael:
    February 7th, 2009 at 7:58 am
    “Hello CMB; I am sorry but you have misunderstood what I have been trying to explain. The emission at the resonance lines is not in addition to thermal emission it IS thermal emission.”

    – That may be the case, but there is additional radiation coming out which is NOT at the resonance lines. I’m not seeing that in your calculations. In fact, you artificially remove it!

    “Does this mean that I am saying oxygen and nitrogen do not have any thermal emissions? YES that is what I am saying at least at room temperatures.”

    – That’s simply 100% false. Thermal emission is simply not limited to emission lines. Quantum excitation and thermal emission are two different phenomena.

    Now, regarding the atmospheric window, here’s your source again.

    http://en.wikipedia.org/wiki/File:Atmosfaerisk_spredning.gif

    As you can see, transmission in the 8-14 um window never gets above 80%, but your calculations assume 100% transmission. Why?


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    michael

    CMB I do not write the laws of nature, I am simply reporting what greater men and women have discovered over the last few hundred years. You can certainly choose to ignor their findings if you like. If you do not work in the field then ignoring or accepting makes no difference other than to your frame of mind.

    If you are active in the field then choosing to ignor what nature has shown to others will simply mean you get wrong answers. Nature is impartial and offers no favours or exceptions.

    Might I suggest that if you feel strongly about all this don’t take my word for it. Get a text book and start reading.


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    cmb

    michael:
    February 9th, 2009 at 7:52 am
    “CMB I do not write the laws of nature, I am simply reporting what greater men and women have discovered over the last few hundred years.”

    – No, you are simply making statements and refusing to back them up with sources.

    “You can certainly choose to ignor their findings if you like. If you do not work in the field then ignoring or accepting makes no difference other than to your frame of mind.”

    – You have not presented their findings – only yours.

    “If you are active in the field then choosing to ignor what nature has shown to others will simply mean you get wrong answers. Nature is impartial and offers no favours or exceptions.

    Might I suggest that if you feel strongly about all this don’t take my word for it. Get a text book and start reading.”

    OK, well, you asked my opinion and you got it. And instead of giving sources to show your method is correct, you made with the insults like the other denialists did.

    I consider you busted until you supply said sources. I gave mine.


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    Phillip Bratby

    Michael: Might I suggest that you are wasting your time conversing with cmb. At 316 he agreed that your work was impressive and that he’d never have the time to analyze it properly. You never claimed that your calculations were exact (eg that the atmospheric window was totally transparent, the real world isn’t as simple as that) and now he is constantly quibbling over your (expert) statements.

    I don’t see anything in your post where you insulted him.

    If he isn’t prepared to look in an undergraduate level physics textbook then that is his choice (or was it high school physics? I can’t remember now).


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    Stephen Wilde

    cmb is the typical intolerant believer.


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    cmb

    Phillip Bratby:
    February 10th, 2009 at 6:47 am
    “Michael: Might I suggest that you are wasting your time conversing with cmb. At 316 he agreed that your work was impressive and that he’d never have the time to analyze it properly. You never claimed that your calculations were exact (eg that the atmospheric window was totally transparent,”

    – Yep. He just operated off that assumption. What do you think the following sentence means:

    “Integrating Plank’s distribution curve from 8 to 14 microns for a temperature of 288K yields a total of 164 watts/m2.”

    What it means, Phil, is that he replaced actual emissions from 8 to 14 with what it would be if the atmospheric window was totally transparent. And you totally missed it. =)

    And you are qualified to insult me, then, because…?


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    Phillip Bratby

    cmb: I realise that you deliberately and totally misinterpret what anyone on this blog writes. Michael has not claimed that his calculations are exact. You can see for yourself that assumptions are made to give an approximate feel for the energy fluxes. This is no different from the work of Kiehl and Trenberth (if you read their paper).

    If my saying this to you is interpreted by you as an insult, then so be it.


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    cmb

    Phillip Bratby:
    February 10th, 2009 at 5:58 pm
    cmb: I realise that you deliberately and totally misinterpret what anyone on this blog writes.”

    – And you are clearly batting a thousand when it comes to understanding what’s going on here. ;)

    “Michael has not claimed that his calculations are exact. You can see for yourself that assumptions are made to give an approximate feel for the energy fluxes.”

    In that case, we can skip the whole “IMPLICATIONS OF THIS ANALYSIS FOR THE KIEHL TRENBERTH MODEL”, right?

    BTW, did you notice that my question about how many GCMs are actually based on K-T itself was completely ignored? =)

    p.s. Turns out that when computing outgoing infrared, using absorption coerfficients is proper and I needn’t have worried about that – which makes it all the more mysterious that they are omitted in the atmospheric window test.

    http://geosci.uchicago.edu/~rtp1/ClimateBook/ClimateVol1.pdf , section 4.4


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    cmb

    Ah, finally found it: Continuum absorption. I knew there was radiation other than at GHG lines, but sometimes my terminology fails me.

    http://geosci.uchicago.edu/~rtp1/ClimateBook/ClimateVol1.pdf – Page 207, figure 4.25

    Michael’s calculated absorption using his lines-based coefficient would seem to be the dotted line. Note, however, the solid line indicating absorption and emission “between the lines”. =)


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    Stephen Wilde

    “In this book I have chosen to deal only with aspects of climate that can be treated without
    consideration of the fluid dynamics of the Atmosphere or Ocean.”

    That pretty much disposes of anything useful in that link then.


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    cmb

    Stephen Wilde:
    February 11th, 2009 at 4:45 am
    “In this book I have chosen to deal only with aspects of climate that can be treated without
    consideration of the fluid dynamics of the Atmosphere or Ocean.”

    That pretty much disposes of anything useful in that link then.”

    – This from the guy who claimed IR could never heat water, and then had to backpedal a couple miles… lol


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    Stephen Wilde

    An Oceanographer of 50 years experoience seems to agree with me:

    http://www.21stcenturysciencetech.com/articles/ocean.html


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    cmb

    Stephen Wilde:
    February 11th, 2009 at 5:56 am
    “An Oceanographer of 50 years experoience seems to agree with me:

    http://www.21stcenturysciencetech.com/articles/ocean.html

    – Hilarious k00ksite, thanks! That one had escaped my notice! But I’m afraid I’m going to have to deny your argument from authority – your source doesn’t have any.

    From the Summer 2008 publication:

    The Subject of Principle: Project ‘Genesis’
    Lyndon H. LaRouche, Jr.
    A discussion of issues of epistemology posed by the assumptions in the method of microbiologist Carl Woese and his associates.


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    Stephen Wilde

    So how exactly does energy from downwelling IR get into the oceans on a significant scale if it cannot get past the first few microns of water and has to deal with the evaporative process ?

    I’m sure you are intimately acquainted with all the relevant science.


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    Stephen Wilde

    cmb, the chap who thinks that Latent Heat of Evaporation comes down with the rain- hilarious.


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    cmb

    Stephen Wilde:
    February 11th, 2009 at 7:56 am
    “So how exactly does energy from downwelling IR get into the oceans on a significant scale if it cannot get past the first few microns of water and has to deal with the evaporative process ?

    I’m sure you are intimately acquainted with all the relevant science.”

    – Having dealt with denialists before, particularly the Creationist sort, I am even more intimately aquainted with backpedaling and goalpost-moving.

    Stephen Wilde: Post #274
    January 31st, 2009 at 8:17 am

    “Air in the open as opposed to a closed environment cannot heat water. Any extra energy whether from conduction or downwelling infra red radiation just increases the rate of evaporation which, because of the water’s loss of the rather large latent heat of evaporation,eliminates any warming effect from the extra energy.”

    – It’s nice to see you revise your statements when needed ,Stephen, but let’s not pretend your revised statement is the one I had trouble with. It’s dishonest.


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    cmb

    342Stephen Wilde:
    February 11th, 2009 at 8:02 am
    cmb, the chap who thinks that Latent Heat of Evaporation comes down with the rain- hilarious.”

    – And here we have not just another (unmoderated!) Ad Hominem, but another in a series of outright hateful lies from Stephen – who apparently still does not understand that 100% of heat of vaporization comes out as condensation cooling.


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    Stephen Wilde

    “all energy taken up by heat of vaporization is always redeposited when PRECIPITATION occurs later”.

    CMB, In view of your above words perhaps we can agree that we all say things in the heat of discussion that need to be adjusted later on. Some of my above points should have been better expressed.

    However it all comes down to whether downwelling IR is powerful enough to heat the oceans despite it’s inability to get past the first few microns and in the face of the evaporative process.

    I really want to know so if you have the evidence please produce it.

    You may dismiss those who see the same problem as ‘kooks’ but that does not resolve the issue.


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    cmb

    Stephen Wilde:
    February 11th, 2009 at 8:28 am
    “all energy taken up by heat of vaporization is always redeposited when PRECIPITATION occurs later”.

    CMB, In view of your above words perhaps we can agree that we all say things in the heat of discussion that need to be adjusted later on.”

    – I can agree to that, but I should note that my statement above is literally true. Any site where water vapor condenses (precipitates) always gains heat exactly to the degree that said water vapor took it during evaporation.

    “Some of my above points should have been better expressed.

    However it all comes down to whether downwelling IR is powerful enough to heat the oceans despite it’s inability to get past the first few microns and in the face of the evaporative process.

    I really want to know so if you have the evidence please produce it.”

    – Actually, it all apparently comes down to whether visible light can heat the oceans, and we know it does. If IR heating of the oceans is also necessary for AGW theory, I haven’t seen that stated yet (but I cannot say it isn’t true).

    So, let’s take a close look at one of the sources I cited for you earlier. One problem is that I can get to stuff from _Science_ because this lab has a subscription, and others here probably can’t, so I will have to do the cut and paste. Comments after the quote.

    http://www.sciencemag.org/cgi/content/abstract/265/5169/224

    “The Role of the Tropical Super Greenhouse Effect in Heating the Ocean Surface
    Dan Lubin 1
    1 California Space Institute and Center for Clouds, Chemistry, and Climate, University of California, San Diego, La Jolla, CA 92093-0221, USA.

    Measurements made by a Fourier transform infrared (FTIR) spectroradiometer operating in the middle infrared (5 to 20 micrometers, with a spectral resolution of one inverse centimeter) imply that there is an anomalously large greenhouse effect over equatorial oceans that is caused by water vapor. As sea-surface temperature increased from 297 to 303 degrees kelvin, the net infrared cooling at the surface decreased by 30 to 50 watts per square meter. Thus, according to the FTIR data, the super greenhouse effect that had been inferred from satellite measurements contributes directly to radiative heating of the sea surface. The data demonstrate that most of this heating occurs in the middle infrared by means of the continuum emission window of water vapor and that tropical deep convection contributes substantially to this super greenhouse effect.”

    As you can see above, radiative heating of the sea surface in the middle infrared spectrum through continuum emission (what Michael and I were on about)has been detected by satellite, and it is apparently enough to diminish cooling of the surface by 30W or more per m^2.

    From the paper itself (it won’t let me cut and paste from the main PDF file, anyone know a workaround?) we also find that recorded mid-IR radiances were 15% greater in convective areas than those where convection was suppressed. This indicates that evaporation is sometimes more successful at removing heat from the sea surface, and sometimes less.

    This is just one study, though. Probably be able to find more later.


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    Stephen Wilde

    IR heating is necessary for AGW theory because all the extra human induced downwelling is in the form of IR and one cannot alter the equilibrium temperature of the whole climate system without also warming up the oceans.

    We all know that IR warms the topmost molecules. The question is whether that extra energy from human sources goes straight back into the air as a resault of enhanced evaporation or whether it finds it’s way into the deeper ocean to change the equilibrium temperature of the whole system, and of course it is relevant as to whether any change in the equilibrium temperature that could occur will take decades or millennia to achieve.

    I have not found anything that satisfactorily addresses those two questions yet they are central to the whole debate.


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    cmb

    Stephen Wilde:
    February 12th, 2009 at 4:49 am
    “IR heating is necessary for AGW theory because all the extra human induced downwelling is in the form of IR and one cannot alter the equilibrium temperature of the whole climate system without also warming up the oceans.”

    – I’ll buy that, with reservations, but there are indirect ways human-induced downwelling could heat the oceans.

    “We all know that IR warms the topmost molecules. The question is whether that extra energy from human sources goes straight back into the air as a resault of enhanced evaporation or whether it finds it’s way into the deeper ocean to change the equilibrium temperature of the whole system, and of course it is relevant as to whether any change in the equilibrium temperature that could occur will take decades or millennia to achieve.”

    Interesting. So, what do you make of direct measurement of increasing ocean temperatures, when solar input hasn’t risen significantly in the last 50 years?

    http://tinyurl.com/agdecj
    http://www.sciencedaily.com/releases/2008/06/080618143301.htm
    http://tinyurl.com/agztud


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    Stephen Wilde

    Solar insolation reached a peak at the top of cycle 21. Since then it has declined but only slowly until recently. Throughout the period it was at a historically high level and so able to add to the oceanic energy store despite a dominance of El Nino events during the same period.

    Normally El Nino releases energy to the atmosphere and reduces the total energy store but the level of insolation was apparently high enough to more than replenish the loss.

    It will be interesting to see what happens now that solar activity is lower.

    As regards indirect ways of human induced downwelling heating the oceans I’ve yet to find any. There is a theory involving the ocean skin but it is also vulnerable to the effects of evaporation, conduction, convection and upward radiation so at present I do not find it convincing.


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    Michael

    Its taken me a while to reply to blog postings firstly because of work committments and then some very serious bushfires near the area where I live.

    So to pick up where I left off; CMB, lets go back to your post 328.

    “Does this mean that I am saying oxygen and nitrogen do not have any thermal emissions? YES that is what I am saying at least at room temperatures.” (my quote)

    - That’s simply 100% false. Thermal emission is simply not limited to emission lines. Quantum excitation and thermal emission are two different phenomena. (your response)

    So you claim nitrogen and oxygen do have thermal emissions. Now lets go a bit further, do they also absorb thermal infrared energy? Like to think about that one? Well lets explore some possible outcomes both ways.

    Lets assume they do not absorb thermal infrared. This would be a delightful prospect. Consider a simple thought experiment – if the gas emits thermal energy but does not absorb it then it must cool down (or do you refute the laws of conservation of energy as well). Yes? No? Now put this gas into a hollow sphere of solid material which clearly does absorb infra red energy. The gas radiates heat which must impinge on the sphere and will heat it up. Of course the inside of the sphere also radiates energy but it is radiating back to itself so it can’t lose energy that way (we will assume the outside of the hollow sphere is well insulated). At the same time the gas does not absorb any energy radiated by the inside of the sphere so it continues to cool down. That means we have net heat flow from from a cold object to a hot one without any power source being necessary. We can tap this temperature difference to drive a heat engine indefinitely. WOW – our energy problems are over, who needs coal fired power stations or nuclear or wind power – we have the CMB heat pump to meet all our needs in a totally non polluting way. Pity about the laws of thermodynamics. Hmm. I suspect if that worked it would hav been discovered some time ago. (In case you like to plead tha gas will heat up by conduction, feel free to assume it is in a container transparent to infrared with a vacuum between the container and the sphere.)

    So maybe nitrogen and oxygen do absorb energy as well as emitting it. Kirchoff’s law holds. But now we have another problem. Gases that absorb thermal infrared energy have a name you should recognise. They are called green house gases. So by your definition nitrogen and oxygen are greenhouse gases. Well we can completley stop worrying about the green house effects of CO2 and CH4 and even water vapour because nitrogen and oxygen dominate them by orders of magnitude!!! Gee thats a relief – debate over, “AGW busted” thats your term isn’t it?

    No doubt you will claim my tone in the above is derogatory. You are correct it is. I can readily accept people who make mistakes (we all do that including myself), I can accept people who do not know something (again that applies to all of us again inculding myself), I am happy to debate different points of view as objectively as possible but I start to lose tolerance when someone adopts an agressive abusive and dismissive approach both to me and others and eventually I respond in kind.

    Up till this post I have tried to interact with you in a courteous and respectful manner but I find that you do not reciprocate.

    Maybe the other participants in this blog would like to kow our respective backgrounds. I will give mine, how about you reciprocating. I have a batchelors and masters degree in engineering but I have spent the last 30+ years employed as a senior researcher/manager for a major multinational spectroscopy company. Our products are sold in almost every country in the world including the USA and all European countries. Many of the inventions I am personally responsible for have been released as new products, and these products have generated revenues well in excess of $500 million.

    By the way you said you answered my original dissertation. As far as I can see what your reply boiled down to was a reference to a site where someone in maybe a year or so might do an experiment which could provide an answer. You may consider that an adequate answer, quite frankly I do not.


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    cmb

    Michael:
    “So you claim nitrogen and oxygen do have thermal emissions.”

    Yes, though I simply repeated what I find repeatedly in the literature. See ‘continuum emission’.

    “Now lets go a bit further, do they also absorb thermal infrared energy?”

    Not to any great degree, unless ionized or otherwise made polar.

    (False dichotomy ignored.)


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    CyberForester

    “Michael:
    February 17th, 2009 at 7:07 pm

    Its taken me a while to reply to blog postings firstly because of work committments and then some very serious bushfires near the area where I live.”

    This raises an interesting point. Not to belittle the human tragedy of the fires in Victoria, there’s the matter of the amount of CO2 that was emitted into the atmosphere. Surely this is a great opportunity to use a “natural” event to measure the impact of CO2 on the climate. Otherwise we would have to rely on something like deliberately emitting a whole lot of CO2 and measuring the effects, and then validating the computer models against that.

    Here’s a golden opportunity for the modellers to predict that will result, and then for everyone to be advised whether the models get it right.


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    Michael,

    I’ve enjoyed your posts and your civility in the face of provocation.

    I have a web site where I would very happy to post your material. http://www.webcommentary.com

    Note also, http://www.webcommentary.com/climate/climate.php

    This line seems to have gone silent. Hope all is well with you.

    Please contact me through the website (Feedback).

    Regards,

    Bob Webster
    Editor, Publisher
    WEBCommentary

    PS: JoNova … great site … added to my links and climate pages.


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    Joanne,

    Please ask Michael to contact me regarding posting of his excellent analyses/discussions.

    Regards,

    Bob Webster
    WEBCommentary


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    bugs

    You seem to misunderstanding the ‘hotspot’. AGW theory says that the troposphere will warm all over the globe.

    You then refer to the IPCC report, and reproduce some diagrams.

    The caption for these diagrams refers to them representing

    “Zonal mean atmospheric temperature change from 1890 to 1999 (°C per century) as simulated by the PCM model from (a) solar forcing, (b) volcanoes, (c) wellmixed
    greenhouse gases, (d) tropospheric and stratospheric ozone changes, (e) direct sulphate aerosol forcing and (f) the sum of all forcings. Plot is from 1,000 hPa to 10 hPa
    (shown on left scale) and from 0 km to 30 km (shown on right). See Appendix 9.C for additional information. Based on Santer et al. (2003a).”

    So the diagrams are for a 100 year period, in which cyclical changes will not be evident. I don’t see what period of time you are using to make your claims?

    The Douglass paper, that seems to be the source of these claims, has a major flaw that is not acknowledged. Recording the temperature at a height of 8km is, of course, problematic. We have enough trouble recording temperatures at 0km as it is. The radiosondes that are used have a problem in that they were designed to record temperatures good enough for weather forecasting, from a moving object.

    http://ams.allenpress.com/perlserv/?request=get-pdf&file=i1520-0442-21-18-4587.pdf&ct=1

    “The apparent cooling trend in observed global mean temperature series from radiosonde records relative to Microwave Sounding Unit (MSU) radiances has been a long-standing problem in upper-air climatology. It is very likely caused by a warm bias of radiosonde temperatures in the 1980s, which has been reduced over time with better instrumentation and correction software. The warm bias in the MSU-equivalent lower stratospheric (LS) layer is estimated as 0.6 ± 0.3 K in the global mean and as 1.0 ± 0.3 K in the tropical (20°S–20°N) mean. These estimates are based on comparisons of unadjusted radiosonde data, not only with MSU data but also with background forecast (BG) temperature time series from the 40-yr European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-40) and with two new homogenized radiosonde datasets. One of the radiosonde datasets [Radiosonde Observation Correction using Reanalyses (RAOBCORE) version 1.4] employs the BG as reference for homogenization, which is not strictly independent of MSU data. The second radiosonde dataset uses the dates of the breakpoints detected by RAOBCORE as metadata for homogenization. However, it relies only on homogeneous segments of neighboring radiosonde data for break-size estimation. Therefore, adjustments are independent of satellite data.”

    As has been noted, if the latest RAOBCORE is used, the models match the observations better. The models are not perfect, but they are a reasonable match. However, what we are discussing now is not the signature of a cooling stratosphere and warming troposphere, which is beyond dispute, but the rate of warming in the upper tropical troposphere. Douglass et al are only seleting one particular part of the global troposphere, out of many available, and arguing the temperature rise there.

    Santer, et al, actually uses the change in height of the troposphere as the ‘signature’

    “Our results indicate that the simulated increase in tropopause height over 1979–1997 is a robust, zero-order response of the climate system to forcing by well-mixed greenhouse gases and stratospheric ozone depletion. At the global-mean level, we find agreement between the simulated decadal-scale pLRT changes and those estimated from reanalyses. While the agreement between simulated pLRT changes and those in NCEP is partly fortuitous (due to excessive stratospheric cooling in NCEP), it is also driven by real pattern similarities. Our work illustrates that changes in tropopause height may be a useful ‘‘fingerprint’’ of human effects on climate and are deserving of further attention.”

    I presume this is not argued?

    The IPCC report refers to other ‘fingerprints’.

    “An important source of uncertainty arises from the incomplete
    knowledge of some external factors, such as human sourced
    aerosols. In addition, the climate models themselves
    are imperfect. Nevertheless, all models simulate a pattern of
    response to greenhouse gas increases from human activities
    that is similar to the observed pattern of change. This pattern
    includes more warming over land than over the oceans. This
    pattern of change, which differs from the principal patterns
    of temperature change associated with natural internal variability,
    such as El Niño, helps to distinguish the response to
    greenhouse gases from that of natural external factors. Models
    and observations also both show warming in the lower part of the atmosphere (the troposphere) and cooling higher up in the
    stratosphere. This is another ‘fingerprint’ of change that reveals
    the effect of human influence on the climate. If, for example,
    an increase in solar output had been responsible for the recent
    climate warming, both the troposphere and the stratosphere
    would have warmed. In addition, differences in the timing of
    the human and natural external influences help to distinguish
    the climate responses to these factors. Such considerations increase
    confidence that human rather than natural factors were
    the dominant cause of the global warming observed over the
    last 50 years.”

    “This pattern includes more warming over land than over the oceans.” You have no argument with that?

    “Models and observations also both show warming in the lower part of the atmosphere (the troposphere) and cooling higher up in the stratosphere. This is another ‘fingerprint’”

    The only argument is the rate of warming. The signature of warming in the upper tropical troposphere and cooling in the stratosphere is evident still.


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    Vincent

    Question
    Open a cold can of coca cola and watch it goes flat as it approaches room temperature. Why?

    I am not a scientist.


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    Water Wizard

    The exact mechanism that causes rain remains unknown despite centuries of research into the subject. If we knew we would be able to solve the world’s water problems. Clearly water has made our planet “livable” under all CO2 levels since life began.

    CO2 cannot cause a hot spot over the equator or runaway temperature rises because water provides feedback mechanisms that control the Earth’s ocean and air temperatures. Such feedback mechanisms change our weather patterns on a macro and micro level. Only some are understood. Modeling of such mechanisms is not possible as much of the mathematics to describe such feedback loops remain unsolved.

    In short if CO2 (or methane etc) heats up the planet, water will cool it. If CO2 cools the planet, water will heat it. If water heats up the planet at one spot it equally cools it at another. There are myriad climatic examples over millions of years and every day. To say we can control or even fully monitor this process when we don’t even know how it rains is ludicrous.


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    Vincent

    “Open a cold can of coca cola and watch it goes flat as it approaches room temperature. Why?”
    I mean Gee Whiz I have been waiting for almost a week, still no answer. Jo, can you help?


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    Vincent, you obviously have something in mind since this is not a page about the missing bubbles from last weeks hot coke. Forgive me, there’s a reason why I don’t have a sign up that says ‘free personal encyclopedia services here’. Why don’t you explain it? …


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    Vincent

    This is an extract (see below) I got from climate science. I hope it will explain the reason for my enquiry and is relevant.

    “Theon subscribes to the warming oceans expel CO2 and cause atmospheric elevation theory (the reverse of the alarmist claim that CO2 drives the warming) and submitted a compelling example: Open a cold can of soda and watch it get flat as it approaches room temperature.”

    I think what Theon was trying to say is; as the coca cola approaches room temperature more carbons are released into the atmosphere until the beverage becomes flat. But, the ambient room temperature (18.C) remains unchanged! If CO2 is the main driver would we see a slight increase in room temperature?

    You might be thinking all this sound a bit bizarre but I believe it will hold its ground in a debate against an alarmist.


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    [...] graph that the planet’s air barely counts (don’t mention the troposphere, or ‘hot spot’? What hot spot?). So now it “doesn’t matter” if air temperatures stay flat like [...]


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    Mike M

    Via icecap.us, here is a new article by Ron House concerning the missing hotspot and his convenient analogy that appears helpful for explaining it to people less inclined to understand science.


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    Michael i dont think anyone on this site is confused,we know the data was manipulated,we know the models are enhanced were needed,we know that these models were made ROBUST,i love that word it is everywhere in there literature,i also read how they will emphasize to Australians in a ROBUST manner that we have 5 sites that we could loose due to global warming,then in the next sentence they say (after 30 years and we have taken the steps that the ipcc put forward we can then tell Australians that there steps have been a success,look the barrier reef is still living,there conversations are very interesting and informative.Lorraine


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    Joe Parale

    Vincent:
    wrote:-
    July 3rd, 2009 at 7:35 am

    “Open a cold can of coca cola and watch it goes flat as it approaches room temperature. Why?”

    Am I being thick, or is it because you’ve relieved the pressure (that’s holding the bubbles in), by opening it…. regardless of temperature ?


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    [...] you asked: We skeptics can offer specific evidence that the carbon-dioxide theory is falsified: the missing hotspot, most carbon dioxide emissions have happened since WWII but it has been warming at a roughly steady [...]


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    Brian H

    Pre-industrial CO2:
    The Collander numbers were cherry-picked. The actual range of readings from about 1820-1920 was from 440 to 260, with the average around 330. E.g., a wide sampling of readings for 1912 all came out right around 340.

    So the AGW thesis is a FAIL in yet ANOTHER way! (Is there no end to the fundamental errors?) And this one is deliberate distortion. As are many others.


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    Brian H

    The evaporation/condensation “heat pipe”: for an exploration of the power of water rising to form clouds in dumping heat, check out
    http://mc-computing.com/qs/Global_Warming/Heat.html
    In effect, the entire heat load released by condensation happens at the upper boundary/surface of the cloud cover, and generates black-body radiation — which is wide band, mostly bypassing the absorption fingerprints of CO2 and H20. It goes pretty much directly into space. The capacity of this mechanism is pretty much unlimited, as long as water is available on the surface to drive it.

    (Venus lacks such water, which is why it is hot. There also happens to be about 1°C day/night difference there, which indicates that the sun has no influence on its surface or atmospheric temperatures. The upper atmosphere evidently absorbs and disposes of all the sun’s contribution to Venus’ heat equation. Overall, CO2 has zero influence.)


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    Brian H

    Joe Parale: yes, you’re being somewhat thick. Leave the cola open and refrigerated and it retains some of its fizz.


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    Brian H

    Vincent;
    Releasing CO2 into a room won’t warm it much; the operation of a GH has is to absorb radiation in specific wavelengths which would otherwise escape. Since the radiation within a room is trapped anyway (unless you have a window or door open), CO2 can’t make much difference.


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    Brian H

    Sorry for the dupe. The second one has a small edit (corrected typo: ‘gas’ not ‘has’.


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    Joe Veragio

    Brian H: @42

    Joe Parale: yes, you’re being somewhat thick. Leave the cola open and refrigerated and it retains some of its fizz.

    Indeed, though not half as much as if you hadn’t opened it.

    The refrigeration argument is a red herring – thoretically true, but with such limited impact that it’s of little relevance in the bigger picture.


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    Brian H

    Joe;
    A cola is an artificially supersaturated solution. Cooling and warming are the dominant solubility variables in the real world. Hardly a red herring!


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    Trevor

    I would like to update this discussion of the “missing hotspot”, with some satellite data, some hard figures on the expected tropospheric warming, and some peer-reviewed papers. In the process, I offer my own (admittedly amateur) analysis on the “missing hotspot”.

    We’ll start with Fu et al (2004). In this paper, Fu says (based on previous work of others) that the global average tropospheric temperature is expected to increase by a factor of 1.2 times as much as surface temperature:

    “GCM studies have predicted a global ratio of ~1.2 (ref. 8) and a tropical ratio of ~1.54 (ref. 14).”

    Ref 8 is “Hansen, J. et al. Climate forcings in Goddard Institute for Space Studies SI2000 simulations. J. Geophys. Res. 107, doi:10.1029/2001JD001143 (2002).”. I cannot access anything more than the abstract for this paper, so if someone can tell me how to see the full text, it would be greatly appreciated. But at any rate, we have a written admission here that GCMs predict 1.2 times as much warming in the troposphere as at the surface. This is, in fact, the “signature” or “fingerprint” of anthropogenic global warming, in that global warming due to natural causes does not result in this much warming in the troposphere.

    Is that what we see in the real world? First, I notice the discussion here of what the “real world” says about tropospheric temperature seems to be based on radiosonde data (weather balloons). But I don’t think weather balloons provide adequate coverage. I think we should be looking at satellite measurements of tropospheric temperatures.

    NOAA has a set of satellites in sun-synchronous polar orbit around the Earth that are used to (among other things) obtain tropospheric temperature data. To quote the Wikipedia article on “Satellite temperature measurements”:

    “Satellites do not measure temperature as such. They measure radiances in various wavelength bands, which must then be mathematically inverted to obtain indirect inferences of temperature. The resulting temperature profiles depend on details of the methods that are used to obtain temperatures from radiances. As a result, different groups that have analyzed the satellite data to calculate temperature trends have obtained a range of values. Among these groups are Remote Sensing Systems (RSS) and the University of Alabama in Huntsville (UAH).”

    So we have two organizations, RSS and UAH, who are estimating tropospheric temperatures from satellite data. What do these two organizations say has been happening with satellite data over the last 30-odd years? UAH says that tropospheric temperatures show a trend of 0.047 K/decade, but UAH is run by two skeptics, Christy and Spencer, so to be fair to the warmists, we’ll go with RSS, which says it’s 0.090 K/decade.

    During that same time period, the surface has warmed 0.17 K/decade. If the GCMs say that the troposphere should warm 1.2 times as much as the surface, then we should expect a tropospheric temperature trend of 0.20 K/decade. But even using the more favorable RSS data, it’s only 0.09 K/decade, less than half of what the GCMs predict. (UAH shows 1/4 of what the GCMs predict.)

    Jo does a good job of discrediting several attempts by warmists to explain away this discrepancy between model predictions and the real world. But the current warmist argument on this topic has progressed to the notion that “stratospheric cooling” negates a portion of the tropospheric warming. The cooler stratosphere, they say, cools the troposphere. On the surface, this makes sense, because we know that heat tends to diffuse from areas with a lot of it to areas with less of it. And so, various authors (like Fu et al, 2004) have tried to come up with ways to “remove” the effect of “stratospheric cooling” from the tropospheric temperature trend before comparing it to the GCMs’ predictions. Notably, Fu was unable, even after such adjustments, to get the real-world global tropospheric temperature trend up to what the models predicted, although his adjusted tropical tropospheric temperature trend was in line with model predictions.

    But here’s my problem with this “stratospheric cooling” explanation of the missing hotspot. Stratospheric cooling was part of the GCMs’ predictions. Even now, they are saying they got that part of it right (and they did – the models correctly predicted stratospheric cooling, though other, non-anthropogenic causes for global warming can also cause stratospheric cooling). And surely these modelers understood heat diffusion, and therefore were aware that the stratospheric cooling would mitigate tropospheric warming to some degree. So it seems to me that the effect of stratospheric cooling was INCLUDED in the models’ prediction that the troposphere would warm 1.2 times as much as the surface. And therefore, it is entirely inappropriate to “adjust” satellite-based tropospheric temperature trends to remove the effect of stratospheric cooling, because the effect of stratospheric cooling is already included in the model predictions.

    On the other hand, maybe the authors of the GCMs, in fact, did NOT factor the effect of stratospheric cooling into their estimates of tropospheric temperature trend in relation to surface temperature trend. That would certainly confirm my suspicions about their intelligence. But it still boggles the mind that even now, after over a decade of overlooking this important factor, noone has gone back and UPDATED the models to include this factor and published NEW estimates of the tropospheric warming trend. That’s why I think it was included all along, and the GCM authors are just remaining very, very quiet about it, now that it contradicts what the tropospheric-temperature deniers are saying.

    But let’s say, for the sake of argument, that it’s true that the GCMs missed the effect of stratospheric cooling on tropospheric temperature trends, and to this day, continued to miss it. What does that mean? It means that the GCMs are overpredicting tropospheric warming by a factor of ~2.2 (that’s when compared to RSS data; compared to UAH data, they’re overpredicting by a factor of ~4.3). But if they’re missing the effect of stratospheric cooling on tropospheric warming, then they’re also missing the effect that the latter would, in turn, have on SURFACE temperatures. If the real-world troposphere warms less than half as much as the models predict, then the real-world troposphere’s ability to warm the real-world surface is less than half of what the models predict. And therefore, the models are overpredicting surface warming, by a factor of more than 2.

    So, in retrospect, maybe it’s true that the models completely ignore the effect of stratospheric cooling on tropospheric temperature trend (and its effect, in turn, on surface warming). That would certainly explain their utter inability to predict the complete lack of surface warming seen over the past decade or so.

    So, does anyone have any information on this? Do the GCMs include the effect of stratospheric cooling, or do they not? Either way, it seems to me, the models are worthless.

    Regards,
    Trevor


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    Trevor

    Oops:

    Damn emoticons. In the third paragraph of my previous post (the quote from Fu et al, 2004), I typed the number 8, followed by a close-paranthesis. This was interpreted as a sunglasses-wearing smily face. If you replace the 8) with the number 8, followed by a close-parenthesis, you will see what I was trying to communicate, and the reference to “Ref 8″ in the following paragraph will make more sense.

    Regards,
    Trevor


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    G.S. Williams

    Greetings from Howick,(shortly to be) Auckland, New Zealand

    Has anyone checked on the HAARP set-up and the chaotic weather occurrences, such as the Russian fires and the Northern Pakistan monsoon floods?

    It would be interesting to see if there is any relationship between them, don’t you think?

    Jo, keep up the great work.

    Regtards.

    G.S. Williams


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    Trevor,

    I enjoyed your recent post (despite the unintended emoticon invasion!). Well-reasoned, clearly thought out analysis.

    Best,

    Bob Webster


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    Trevor,

    Geez, I just noticed the date on your post … for some reason I received a slew of links to JoNova’s articles I’ve visited (and commented to) before. I thought your post was recent. Nevertheless, my comments stand. Anything new on this item since April?


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    Brian H

    Bob;
    Her sites got spam-bombed, and before she could clean out the garbage, the automatic notification systems kicked out “update” notices to everybody.


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    Brian,

    Thanks … that does explain the surprise messages and odd dates! I believe it is deliberate. I had to rebuild a site using php when asp became so vulnerable that I could no longer protect online databases using MS-SQL and asp. Microsoft’s solution: convert to aspx (which required a complete reprogramming of the many routines I had coded). I decided to switch to a Linux-based service and php. Should have done it much sooner. No MS security problems. Of course, with a spam-bomb, I’m not aware of what can be done to stop that. It is a behavior that is all too typical for those who would find Jo’s site worthy of attack.

    Bob


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    waguy

    Whats with all the “Chicken Little” politics these days ?

    How much money does a politician have to throw in the air to make the weather change ?

    Is the carbon price really about climate control or chanelling more $ through the hands of the wealthy ?

    And when will people finally come to terms that they can not change the weather and that any effects by humans almost doesn’t rate ? I dare say some will NEVER admit it.

    Ummm … I’m no expert. But I know this as a fact. The atmosphere absorbs only as much carbon as it wants to. Any surplus is diffused by various means.

    No tax, no monetary amount, no politician, no protest song, no advertising campaign can change that fact.

    Here’s a tip from a layman and I’ll keep it simple. Humans can’t control the weather.

    Maybe Julia Gillard should introduce a Solar Flare Tax .. it makes just as little sense as a carbon tax.


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    Dusty

    After reading through all the great posts accumulated here over a period of a couple of yrs. it has reinforced my lay person’s opinion of Man Made Global Warming.
    I made up a simple acronym for all the Man Made Global Warming advocates to explain any temp. increases of our world if indeed there is any.
    ITSS
    Stands for, ‘It’s the Sun, stupid’.


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    r.m.b

    Have any of you thought of the proposition that the oceans do not absorb physical heat only radiation. The reason- surface tension. I can not heat a bucket with a heat gun. Try it.


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    Joe V.

    Rmb @56.
    Eh? Ok so call it radiation if you don’t like heat. Fundamentally it’s all energy and it’s the energy that does the heating.


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    Brian H

    rmb;
    a confused comment, but brings up a useful physics point.
    Heat radiation is absorbed in the first mm or so, and will therefore result in enhanced evaporation. Set two identical buckets of water side-by-side and shine your heat gun at just one.

    Watch which pail dries out first. The surface water of one was heated faster and evaporated faster; essentially it was “boiled” away slowly, from the top down. The heat energy went into the latent heat of condensation/evaporation, and resides in the water vapour generated. If a cool surface was held near the top of the bucket, much of the vapour would recondense on it and give up its latent heat, thus warming that surface.


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    WatchTheSources

    Interesting comment at the end of Jo’s piece, referencing across to David Evan’s.

    “On David Evans site there’s a full definitive explanation of the missing hot spot and all the common attempts to rebut it on one pdf here”

    [SNIP: It's well known that David Evans and Jo Nova are married. So? You haven't got any evidence the hot spot argument is wrong. ...No.]


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    Brian H

    The terminology discussion made me realize the Alarmists are using “change” in a special way. They mean it as an active verb, as in “alter” or “fiddle”. So I think it should be understood to mean “Climate Destruction”. Which is, of course, whack-O.


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    ebm

    A couple of years ago, the Scripps Institution of Oceanography did a study of solar radiation warming the ocean through the cloud cover over the Fiji area of the Pacific. As I understood the study, it was intended to prove that the high-altitude cloud cover (i.e., clouds that were facilitated by a peculiar mechanism of cloud-forming nuclei of ionized CO2?) had a net warming effect on the ocean. Isn’t this cloud-cover-related warming theory the real crux of the Greenhouse CO2 theory? (The UCSD documentary I saw on our local access TV here in San Diego certainly seemed to suggest that it is!) Anyway, the Scripps study was elaborate. The scientists flew one impressively outfitted plane above the clouds to compare solar radiation coming from above with radiation reflected back upwards. They flew another specially equipped plane right below the cloud cover looking up to measure the radiation that was being transmitted through the cloud bank and comparing this with the amount of radiation being reflected back upward by the ocean. A third plane was flown right above the ocean looking upward and downward in the same way. The bottom-line problem with the Scripps Study is that it found only a net cooling effect of the cloud cover. (Duh!) The Scripps scientists seemed pretty sheepish as they confessed the failure of their study–which is another reason why I have assumed that the cloud-cover effect is the crux of the CO2 theory of AGW. (In my opinion, the scientists did not have a good grasp of radiation physics in the first place.) Has anyone on the forum read any published report of this elaborate, expensive (time-wasting/unnecessary) study?


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    The reaction of Scripps “scientists” who set out to prove one thing and ended up collecting evidence that pointed to an opposite effect strongly suggests a lack of the requisite objectivity and integrity needed to perform legitimate scientific research.

    This is not unlike the reaction of warmist “scientists” to the CERN CLOUD research that essentially confirmed Svensmark’s cosmic ray/solar wind theory (which had already been independently confirmed by experiments conducted by Svensmark). Yet to read warmist reports on CLOUD conclusions, one would get the idea that all that research really showed nothing of consequence!

    AGW peddlers have no real credibility with real scientists.

    This is the first I’ve heard of the Scripps study. Very interesting.


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    It’s really very complicated in this active life to listen news on TV, so I simply use web for that reason, and obtain the most recent news.


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    [...] The missing hotspot « JoNova - The ‘Hotspot’ is crucial to the climate debate. [...]


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