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Comments 123751 to 123800:

123751. theendisfar at 02:09 AM on 23 February 2010
        Visual depictions of CO2 levels and CO2 emissions
        Let's suppose (in the worst case) every ounce of IR energy were absorbed within a few meters. This would simply raise the radiative heat source a few meters off the ground... or is the energy just going to stay there forever hovering over the ground? That would be on average 240 W/m^2. For dry air, it takes ~1,300 joules to raise a cubic meter of air (1.3kg) 1 degree C. So it will take approximately 5 seconds to raise the temp 1 C. As the temperature of that cubic meter of air increases, its density decreases and moves the heated volume skyward to be replaced by a lower temp volume of gas (nature abhors a vacuum) and the process repeats. As the volume rises, pressure decreases and so does the temp from PV=nRT. It takes energy to move that volume of gas, in fact it takes ~88,000 Watts to move a 1 m^2 column of dry air 1 meter/sec skyward. The Earth only radiates at 240 Watts, which makes sense given that Radiation is the least efficient means to transfer energy while convection is very efficient. Entropy states that energy will take the path of least resistance or the most efficient path. Once Convection is no longer available as a means to transfer energy (i.e. Tropopause), then Radiation becomes the only means of cooling. Note that the Earth's convection zone, the troposphere, would only be 8 mm high if the planet was 100 meters in diameter. While that is a very short distance, convection moves massive amounts of energy within that zone. The wind that drives sailing vessels has huge amounts of force behind it. That energy comes from convection, which comes from the surface heating the air just above it.
123752. KR at 01:53 AM on 23 February 2010
        Is CO2 a pollutant?
        suibhne: Once again you mistake the tree for the forest. Simple black body radiation (yes, simplifying for this discussion) emits from any object at levels corresponding to temperature. The Earth radiates the ~390 w/m2, plus another 100+ or so in conduction/evaporation. [Note that the measured bidirectional energy flow is 4x higher in radiation than conduction/convection.] The atmosphere radiates 342 (note, less!) towards the Earth. That and the 168 solar irradiance sum to (wait for it) 0. That's important, suibhne, _zero_. This is a steady state thermodynamic balance, and WORK is not being done. The atmosphere bounces a great deal of the energy emitted by the earth right back to it (like a silvered thermal blanket) - no work is done, just a different steady state condition than with no atmosphere. You have again argued from a portion of the equation, not the sum; looking at a part of the energy flows rather than the summation. As for the Earths surface being warmer than space, the solar irradiance impinges on the earth, lower wavelength/lower energy (IR) is emitted (simple entropy there, the earth isn't a perfect mirror), and CO2 with an IR absorbance peak retains it. Enough said. You first need to look at the summations in the steady-state thermal diagram, and realize that if work is being done it wouldn't be steady-state. Second, "It is impossible for HEAT to flow from a lower temperature atmosphere to a higher temperature planet unless work is done on the system to make it possible" realize that the presence of something warm (the atmosphere) keeps neighboring things warm (the Earth) by slowing/balancing energy emission rates. Again, this is a summation of all energy flows. And third, the energy flows of IR, conduction, and evaporation are easily measured and known - the GT assertions apparently denying IR energy exchange to the contrary are simply and provably wrong. I realize this isn't the last word on the topic; I assume that you will have some response. However, this is the last that I will post unless you have an actual and substantive point.
123753. theendisfar at 01:42 AM on 23 February 2010
        Visual depictions of CO2 levels and CO2 emissions
        Alexandre, Why thank you! I welcome your assistance, for starters though, let's just begin with ONE formula and as many coefficients as required. Your language suggests you have a superior understanding or was it condescending in nature. I would like to find out.
123754. carrot eater at 01:29 AM on 23 February 2010
        Is CO2 a pollutant?
        suibhne Finally, you've decided to explicitly accept the G&T position. OK. Now, where in the Trenberth diagram is heat flowing the wrong way, suibhne? Please point out exactly where the wrong way transfer is.
123755. CBDunkerson at 01:26 AM on 23 February 2010
        Is CO2 a pollutant?
        Actually, both the discovery of the greenhouse effect and thermodynamic laws were first announced in 1824. However, the problem here isn't that the greenhouse effect violates the laws of thermodynamics... it is that you don't understand those laws. As you are attempting to apply them the Earth could be no warmer than the temperature generated by incoming solar radiation... yet it is ~32 C warmer. The planet is NOT a solid ball of ice. Ergo, your understanding MUST be incorrect. How is that possible? Well, for starters you are trying to determine entropy while leaving the energy SOURCE (i.e. the Sun) out of your system of observation (atmosphere and planet only).
123756. danielbacon at 00:53 AM on 23 February 2010
        Have American Thinker disproven global warming?
        http://www.eumetsat.int/.../pdf_conf_p50_s9_01_harries_v.pdf I think this is the newer study to the (Harries 2001). If it is the place it above and delete my post thanks.
123757. Dennis at 00:45 AM on 23 February 2010
        Have American Thinker disproven global warming?
        Remember last weeks postings on the Dunning-Kruger effect? Well, Gary Thompson's writing is a perfect example of it.
123758. Arkadiusz Semczyszak at 00:01 AM on 23 February 2010
        Have American Thinker disproven global warming?
        It seems to me, that the main theme here is "skepticism" about the American Thinker, not only "Longwave radiation" ... Is so surely my earlier (deleted) comment was not about what You write?
        Response: That comment was deleted because it was off-topic - it seemed to come out of left field and I struggled to see what it had to do with the discussion at hand. I'd say it was more appropriate in a discussion of what's causing the rise in atmospheric CO2.
123759. suibhne at 23:50 PM on 22 February 2010
        Is CO2 a pollutant?
        CBDunkerson It is impossible for HEAT to flow from a lower temperature atmosphere to a higher temperature planet unless work is done on the system to make it possible. Why do you think that every Physics or Thermodynamics textbook would back me up on this? The laws of thermodynamics were there before and after any supposed new theory such as Greenhouse theory. They can not be set aside.
123760. Arkadiusz Semczyszak at 23:38 PM on 22 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        HumanityRules My comment is a little late, but ... - Warming, e.g. in the Older Peron - was global, but higher in NH. The current warming is also greater for NH. Responsible for changes in the THC - North Atlantic deep - below the shelf - narrows the "bottleneck" ... The spectacular example - most of Antarctica, over the past 35 years, is cooled (http://www.sciencedaily.com/images/2008/05/080507132855-large.jpg), which is typical for the Millennium cycles, although the reasons may be Miscellaneous (e.g.: "A doubling in snow accumulation in the western Antarctic Peninsula since 1850." E.R. Thomas et. al., Geophysical Research Letters, VOL. 35, L01706, doi: 10.1029/2007GL032529, 2008).
123761. CBDunkerson at 23:27 PM on 22 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        AndrewY, assuming that you are referring to Figure 2... it should be understood that the sharp dip shown 'coming up' is the result of a randomly placed major volcanic eruption (as can be seen by the corresponding downward spike in the black line at the top of Figure 3). Thus, while a volcanic eruption could happen in that time frame and have that sort of short term cooling impact, there is no scientific data suggesting that this WILL happen... our ability to predict volcanoes is extremely limited. The random eruptions were included only to show that they have little impact on the long term trends. That said, your observation about short term fluctuations testing "faith in science and reason" is very much what we've been living through this past decade of only mild warming. If it, and the accompanying denial, continued we could very well miss our chance to stop GHG emissions from reaching dangerous levels. However, that seems unlikely to be the case... predictions for the current year suggest that it is going to have a high temperature anomaly. Indeed, last month was the hottest January ever recorded and the third highest anomaly month (after two in 1998) in the UAH records. February looks on track to be similarly high. If predictions for 2010 hold out then it is likely that carefully constrained 'no statistically significant warming since 1995' bit will go poof.
123762. Ned at 23:09 PM on 22 February 2010
        Have American Thinker disproven global warming?
        HumanityRules, I think it's great that you're asking so many questions. My question to you might require a little introspection. I don't know whether you had seen the original post about this graph at "American Thinker," but if you had, would you have put in a comparably aggressive effort to question Gary Thompson's representation and conclusions? In other words, are you this skeptical towards claims on both sides of the issue, or only in one direction? Perhaps you would have ... but if so, you would have been pretty much alone among Mr Thompson's audience. I didn't read through all the comments over there, but I did examine the first 20 posts. Not a single one raised any questions about Gary Thompson's mis-representation of the paper. Instead, here is a summary of those 20 comments:
        • Expressing congratulations: comments 1, 2, 12, 15, 18, 20
        • Promoting conservative political agenda: comments 2, 4, 7, 8, 10, 11, 12, 14, 17
        • Attack on scientists: comments 3, 5, 7, 9, 10, 13
        • Statement that AGW is a hoax/fraud/scam: comments 10, 11, 13, 14, 17
        • References to Al Gore: comments 7, 11
        • Praise for Lindzen or other prominent "skeptics": comments 9, 10, 15
        • Linkage to other climate-"skeptic" issues: 13 (snow this winter), 18 (claims of ice age in 1970s), 19 (Medieval Warm Period, hockey stick, etc.)
        • Linkage to other issues: comments 10, 17 (both advocating use of DDT as a pesticide)
        In other words, there's a complete absence of skepticism over there. Indeed, there's little more than self-congratulatory backslapping, repetition of widely available "talking points," and a tendency to see everything in the light of a particular current US conservative political agenda. Whatever your position on AGW is, one should at least acknowledge that John Cook has done an admirable job of creating a site here where science is discussed openly and critically, and where politics and personal attacks are mostly left outside.
        Response: After posting this article, I was a bit annoyed with myself that I forgot to read the comments on the American Thinker article - there may have been someone who raised similar objections and hence the author's response would've been interesting. If all comments were similar to the first 20, I'm glad I didn't waste my time.
123763. HumanityRules at 21:50 PM on 22 February 2010
        Have American Thinker disproven global warming?
        Whoops my bad. They do mention the 1997 El Nino but not the 1970 La Nina. Still not so happy with the one liner suggesting it may just shift the base line. The reversal of the trade winds during these two periods is surely going to have a major impact on the atmosperic components over the Central Pacific and elsewhere.
123764. Argus at 21:33 PM on 22 February 2010
        Climategate CRU emails suggest conspiracy
        Riccardo : '' None of them ever said they were going to delete the email.'' Maybe not, but this quote is rather close (from Phil Jones). Close enough for me!: ''If they ever hear there is a Freedom of Information Act now in the UK, I think I'll delete the file rather than send to anyone...''
123765. AndrewY at 21:30 PM on 22 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        First, thanks a lot, John, for your work on this site, it is a great resource and your writing is clear, accessible and objective. I have to say that I see a very worrying feature in this prediction of the global temperature anomaly. In all cases there is a brief rise and then a considerable decline in the global temperature over the next decade. After that (from around 2020) the global temperature climbs very rapidly. This is presumably because natural climate variation/cycles first hold back the global warming trend, then after 2020, combine to reinforce it. I realise that climate models don't predict these relatively short term trends very well, but if this temporary reversal of the warming trend actually happens in this decade, it will make it a lot more difficult to convince politicians and the public that global warming is a serious problem that requires radical changes to the way we generate and use energy (and resources). How terribly ironic if such a temperature decline actually happens just at the time when a concerted effort to reduce GHG emissions is most vital! It will truly test humanities faith in science and reason.
123766. Riccardo at 21:22 PM on 22 February 2010
        Have American Thinker disproven global warming?
        HumanityRules, 1) no, different absorption bands have different strength. As you can easily see in panel a, the band at 970 cm-1 is minuscule. The difference is scaled proportionally so is minuscule as well. 2) From the paper: "All the principal features due to changes in CO2, CH4, O3, temperature and humidity are well modelled, as are the small changes due to the chlorofluorocarbons (for example, at 850 and 920 cm-1) and weak CO2 bands (for example, at 795 cm-1)." It appers that John actually read the paper. 3) didn't understand what the point is. 3) this paper shows the increasing absorption of CO2 and other GHG. This is unambiguous whatever H2O might have done. The conclusion that it "[...] is consistent with concerns over radiative forcing of climate" is appropiate.
123767. 70rn at 21:15 PM on 22 February 2010
        Have American Thinker disproven global warming?
        @7 The absorption regions used these graphs - specifically the ones between 700 - 800 cm^-1, are not attenuated by h2o and as such change at that range in the spectrum cannot be attributed to it. Below 700 cm^-1 the absorption regions of co2 and h20 begin to overlap, so change in that region can be correlated to co2 alone. Point 2. There is no co2 absorption range at 970 cm^-1 that i am aware of, though i believe there to be a 03 region somewhere there about.
123768. Pierre-Normand at 21:15 PM on 22 February 2010
        Have American Thinker disproven global warming?
        I had posted a comment on JREF regarding this Smoking Gun. It's not so very often that I can be ahead of SkepticalScience!
        Response: It's not that hard to get the scoop on me - I'm hardly known for my promptness or punctuality :-)
123769. HumanityRules at 21:07 PM on 22 February 2010
        Have American Thinker disproven global warming?
        Another question. Is the Central Pacific data comprimised by the fact that Apr-Jun 1970 was the start of one of the strongest La Nina this century while Apr-Jun 1997 was the start of one of the strongest El Nino. There is no mention of this fact in the Nature paper.
123770. 70rn at 20:50 PM on 22 February 2010
        Have American Thinker disproven global warming?
        I may be foolish to ask such a question, but what does brightness temperature actually mean. Is n brightness temperature (K) equivalent to the amount of energy necessary to create a change of n °s K, per wave-number cm ^-1? And if so can you relate such changes (obviously not directly to surface temperature over the same period? The lack of data below 700 cm ^-1 is not so surprising as there is overlap with water vapour beyond this point and as such it may be more difficult to detect changes. A thought, atmospheric circulation is more complex further away from the thermal equator, and energy/temperature cycling is more dependent upon atmospheric movement than at lower latitudes. Is it possible co2 has a greater effect in part because of this?
123771. CBDunkerson at 20:45 PM on 22 February 2010
        Is CO2 a pollutant?
        Suibhne wrote: "You seem to insist that HEAT flows from a lower temperature atmosphere to a higher temperature planet. No Physics or Thermodynamics textbook will support you in this." This central argument in the G&T paper is, evidently, an article of faith on which you will not be swayed. It is however clearly false. As has been shown in countless examples to the contrary. Were it true the 'effective temperature' and 'actual temperature' of all planets would be the same (and Earth a large ball of ice), two heat lamps in close proximity would result only in the cooler one warming while the warmer one is magically unaffected by the other heat source, those reflective space blankets wouldn't work because they are colder than the human body they are applying heat to, and so on through the various thought experiments you have been unable or unwilling to follow.
123772. HumanityRules at 20:38 PM on 22 February 2010
        Have American Thinker disproven global warming?
        I'd be interested in your questions to the author and his replies mainly because if there is a small critisism I have of your presentation of publications that support AGW it's that you under-represent the limitations of the work. For my part there would be a couple of questions. 1) Figure 2 also has a third graph (c) which shows CO2 absorption around 970cm-1 but there appears no difference in the 1970 and 1996 data. Is this an issue? 2) I'd just query whether you too are seeing what you wish to see in the same way that the American Think guy is. On the 2b graph you state that the top and middle graphs show strong agreement. Are you making this statement based on eyeballing the graphs? Because in the 700cm-1 region the observed difference seems smaller than the modelled difference for the central pacific. 'Observed - model' would be useful here because deviation from the model actually looks significant at the important 700cm-1 wavelength compared which much of the rest of the graph. 3) Is there any problem associated with a ten-fold difference in the data points from 1970 and 1996? While they describe the process for discarding unreliable data and state the absolute numbers of data points used for each time point they don't state what % of data is thrown away for each time point. Is the tenfold difference due to data collection or data rejection? If you are rejecting 50% of the 1996 data but 95% of the 1970 data you'd have to worry what effect this is having on results. 3) Given that the author makes the following statement "But this relationship is complicated by several feedback processes - most importantly the hydrological cycle - that are not well understood" And the author also aknowledges that changes in atmosperic ice would give a result indistinguishable from the observed results shouldn't there be a huge rider on the interreptation of the results. Since H2O has to be ignored in this and it is the most potent greenhouse molecule shouldn't the conclusion just be that we are unable to rule out CO2 having a greenhouse effect and save final judgement for when we do better understand the role of water in all of this?
        Response: Here are the questions I sent (italic) and John Harries' responses (JH). Very prompt and very detailed, he's a class act:
        
        JC: I was curious as to why the comparisons of spectra only went down to 700cm-1 when the IMG data went down to 600cm-1. It seems there would be more CO2 absorption at lower wavelengths.
        
        JH: The signal to noise ratio below 700 cm-1 decreased rapidly, so the quality of the spectra below this point was not good. The error bars became larger than the expected differences, so this region was not used.
        
        JC: How did you work out the difference between the IMG to IRIS data?
        
        JH: For the observations, measurements from both the IRIS and IMG instruments are available. These were calibrated radiometrically by the scientific teams that carried out each project. We had to process the data so that the spectral resolution was the same (choosing the resolution of the lower resolving instrument - IRIS), and we tested that the data processing in each case had not introduced artificial differences (apodisation function, field of view), and that the spectral scales were equalised (comparison of spectral wavenumber of individual features). Once all these effects had been taken into account, so that the two spectra were directly comparable, we took the difference to produce Figs 1a and 1c. For the theoretical curve (Fig 1b), we have programs that can simulate the upwelling spectrum at the top of the atmospehre, if the state of the atmosphere below is defined. We have data for the atmosphere for both periods, for the location chosen, and so these data were input into the program, and two spectra generated. The difference between these two spectra produces the difference spectrum betwen 1970 and 1997. Note that the theory curve confirms that the shape of the two observed difference spectra in the CO2 band is correct.
        
        JC: I was wondering if your analysis determined whether the total amount of outgoing longwave radiation had decreased from IRS to IMG? If so, is it mentioned in any of your papers (I couldn’t find anything but I may have missed something)?
        
        JH: It's a good question. The problem is that the observations do not cover the whole of the outgoing spectrum, and so it is impossible to obtain a total integral across all wavelengths. The 'missing' part of the spectrum is mainly at lower wavenumbers than about 500 cm-1, where there are effects due to the water vapour feedback.
        
        Even if we could integrate the whole of the outgoing IR, there is still the shortwave (SW) side of the net radiation balance, which we would need to consider to look at the total energy change, in and out.
        
        One other point: to sum up all the energy you would have to use the radiance spectrum, not the brightness temperature spectrum. Though they are equivalent, the transform from one to the other is not linear. So, integrating brightness temperature would not be easy to interpret.
        
        At present, therefore, the spectral measurements are not available to do the integration you suggest, which is why you found no mention in my papers. If you are interested in understanding any changes in the measured incoming and outgoing radiation, the best approach is to use the broad-band (non-spectral) Radiation Budget measurements from instruments such as NASA's CERES.
123773. Steven Sullivan at 20:26 PM on 22 February 2010
        Did Phil Jones really say global warming ended in 1995?
        George Will is at it again. Ugh. "Global warming skeptics, too, have erred. They have said there has been no statistically significant warming for 10 years. Phil Jones, former director of Britain's Climatic Research Unit, source of the leaked documents, admits it has been 15 years. " http://www.washingtonpost.com/wp-dyn/content/article/2010/02/19/AR2010021903046.html
123774. stevecarsonr at 20:22 PM on 22 February 2010
        Have American Thinker disproven global warming?
        Nice article. Most people have only the haziest notion of what radiative effects take place in the atmosphere. So any story sounds plausible. In fact, lay out the actual basic facts of longwave upwards and downwards flux at the surface and at top of atmosphere and there will be a lot of people telling you that you are wrong, the numbers are wrong, it breaks the laws of physics, you are mixing up shortwave radiation, and so on.
123775. Riccardo at 20:11 PM on 22 February 2010
        Have American Thinker disproven global warming?
        eyeballing + accurately choosen graph = demonstrate almost anything Try yourself, is a funny game to play with friends.
123776. suibhne at 19:24 PM on 22 February 2010
        Is CO2 a pollutant?
        Ned carrot eater Philippe Chantreau KR You seem to totally ignore the atmospheric insulation provided by conduction and convection effects. The wind and tides redistributing thermal energy around the planet. Geothermal effects, resistive effects, wave thermal effects, in keeping the planet warm. Overemphasis on radiation, will distort the reality of the situation.
123777. suibhne at 19:14 PM on 22 February 2010
        Is CO2 a pollutant?
        Ned carrot eater Philippe Chantreau KR You seem to insist that HEAT flows from a lower temperature atmosphere to a higher temperature planet. No Physics or Thermodynamics textbook will support you in this. However if you say that co2 and water vapour form a machine to do work on the atmosphere then at least we could look into that. As far as I know no body is prepared to be as explicit as this.
123778. Stuart at 19:13 PM on 22 February 2010
        Have American Thinker disproven global warming?
        Now this is just embarrassing. The "skeptics" continue to let the blind lead the blind.
123779. David Horton at 19:12 PM on 22 February 2010
        Have American Thinker disproven global warming?
        Think the first word in your title should be Has, not Have, John, but more to the point - the statistical technique of "eye-balling graphs" is such a common feature of denier science that we could begin calling them "Eyeballers".
123780. Doug Bostrom at 18:59 PM on 22 February 2010
        Have American Thinker disproven global warming?
        "Therefore, the AGW hypothesis is disproven." If only it were that simple.
123781. Riccardo at 17:58 PM on 22 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        What Berényi Péter did is a sort of smoothing under the assumption of linearity of the 20 years period. This assumption is clearly not supported overall by the data and so his smothing procedure is flawed. Why not use standard smoothing filters?
123782. Bern at 17:20 PM on 22 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        Occam's Razor would suggest that BP has made an error. I think more detail is required on exactly what calculations have produced that 0.6ºC/century cooling rate, so that others can check it, as such a result is contrary to considerable other evidence & scientific publications. Extraordinary claims require extraordinary proof, as Carl Sagan once said.
123783. PeterWinters at 15:22 PM on 22 February 2010
        Did Phil Jones really say global warming ended in 1995?
        There seems to be a number of mistakes journalists make in reporting on this issue. 1. Understanding that 'no statistical difference' can reflect on either the data available or the underlying phenomena ... and Phil Jones made it clear that it is due to the limited amount of data available. 2. Understanding that science is never 'settled', it is always conditional (as Mike Hulme is particularly keen to argue). 3. Having a good appreciation of what constitutes good evidence for / against climate change. 4. Understanding the way major scientific debates are conducted & the strong emotions it can evoke (e.g. as Darwin's ideas did in the 1860s) In Canada, the journalist, Margaret Wente makes a number of these mistakes (IMHO) in this article in the Globe and Mail http://www.theglobeandmail.com/news/opinions/the-science-isnt-settled-now-what/article1469050/
123784. qwertyuiop at 15:10 PM on 22 February 2010
        There is no consensus
        you do realize that there cannot be skeptics if you are talking about a theory. climate change is a theory so how can there be skiptics
123785. Ned at 13:08 PM on 22 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        Marcus, I tried that as well -- but I used lower-troposphere temperatures, and I looked at July data in the northern hemisphere only (since that is what Berényi Péter says he did). He claimed "No warming for July. In this case the cooling is 0.6°C/century." Like you, I found +1.65°C/century warming for July in the northern hemisphere, using the RSS lower troposphere data for the whole period of record (1979-present). Given the very, very close match between satellite and surface temperatures, I am confident that the surface records would give similar results. It seems pretty obvious that BP has mixed something up somewhere.
123786. Marcus at 12:13 PM on 22 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        According to my plotting of global July Temperatures from 1979-2009 (RSS data for Mid-Troposphere temperatures), there has been a warming trend of +0.17 degrees per decade for July alone. For the June-August period, the warming trend has been +0.16 degrees per decade. So I'd love to know how Beranyi has gotten his figures.
123787. philipm at 12:06 PM on 22 February 2010
        The Dunning-Kruger effect and the climate debate
        There is some interesting stuff at JPL about how well CO₂ is mixed into the atmosphere. Because of the large fluxes involved it is not quite as uniformly mixed through the height of the atmosphere as oxygen or nitrogen:

        There is a definite difference in concentration between the troposphere (pretty well mixed) and the stratosphere ("old" air, CO2 concentration lags that of the troposphere by several years and the lag is greater at the higher latitudes).

        However it's clear that measuring at isolated locations should give a consistent picture of any trend. If you support the right of scientists to work without harassment and political attack, sign my petition at http://www.petitiononline.com/clim4tr/petition.html
123788. Ned at 12:03 PM on 22 February 2010
        Is CO2 a pollutant?
        KR, when using the Moon as an example, keep in mind that the Moon has a lower albedo than the Earth. So if there were no greenhouse effect, the Earth would actually be even colder than the Moon.
123789. Ned at 11:58 AM on 22 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        Thanks for the heads-up on that paper, Chris. It is freely downloadable, and it's very readable. I would encourage anyone with an interest in solar/climate connections to peruse this paper.
123790. carrot eater at 10:39 AM on 22 February 2010
        Is CO2 a pollutant?
        suibhne: It's more than just CO2; water vapor accounts for more of it than CO2. You are just giving emotional objections at this point - that something just doesn't sound right to you, for unexpressed reasons. That isn't sufficient. Again, please clearly state where there is a violation of the Second Law. G&T think there is one; do you agree? As for not corresponding to reality: I've shown you that these things can be measured. Longwave IR coming down towards the surface is not at all negligible. Reality is the greenhouse effect. Without it, the Earth would be a rather cold place.
123791. Philippe Chantreau at 10:20 AM on 22 February 2010
        Is CO2 a pollutant?
        That you would total up opposing IR flows as "available" energy confirms my doubts on your overall understanding of the process. Such an abuse of language is rather suprising from someone posing as a stickler on definitions. As for this question: "do you not think this is rather odd?" No, I don't. The nice climate we've been enjoying, sustained with only 342 w/sq.m exchanged at the surface, would be the oddity.
123792. KR at 10:16 AM on 22 February 2010
        Is CO2 a pollutant?
        Gah - sorry, bad simple math, typing too fast: The moon has 107-153/2 = -23C average surface temp, versus ~15C average surface temp on Earth, difference of 38C. Difference between the moon's -23C and Earth's 15C surface temp is due to the insulation of the atmosphere, and the high levels of energy interchange at the surface are because the surface is WARM. It's that simple, suibhne.
123793. KR at 10:13 AM on 22 February 2010
        Is CO2 a pollutant?
        suibhne, the level of energy flowing/exchanging at the surface IS much larger than the level of energy at the top of the atmosphere, due entirely to the insulating properties of the atmosphere. If we didn't have an atmosphere the surface of the Earth would resemble the Moon; 107C average during the day, -153C average at night, summing to -46C surface temperature. As it is the average surface temp of the Earth is (sorry for vagueness, folks) around 15C, over 60C warmer. Without the atmosphere the surface of the Earth would quickly cool to match incoming solar irradiance. The outgoing energy from the surface (390 w/m2, plus 24 in conduction and 78 evaporative, according to the figure we've been discussing) is kept at ~15C by solar irradiance _AND_ heat reflected down from the atmosphere (342 or so?). Increasing CO2 will cause more heat to be retained by the atmosphere, directly resulting in a warmer atmosphere and surface - that's very simple. suibhne, you continue to construct incomplete thought experiments (your double IR solar panel), argue over definitions of heat and energy, and quite frankly insult other posters thermodynamic knowledge, but it really is this simple: the atmosphere insulates the earth and allows it to be >60C than the moons surface with the same irradiance. Increasing the insulating properties of the atmosphere with higher CO2 (and through positive feedback water vapor) levels will make the earth warmer. Hence global warming...
123794. suibhne at 09:59 AM on 22 February 2010
        Is CO2 a pollutant?
        carrot eater This atmospheric forcing of co2 is really powerful almost three times as much energy available at the surface as supplied by the Sun. Its a pity about the inconvenient facts of thermodynamics but they will not fade away. Any theory or computer model based on stuff like this must fail as it does not correspond to reality. I don't know who the "we" are in your last post I only speak for myself,but I never find it hard to be polite.
123795. Alexandre at 09:44 AM on 22 February 2010
        Visual depictions of CO2 levels and CO2 emissions
        RSVP, In a sense, yes. Atmosphere is a poorer radiator than solids or liquids. Gases are terrible black bodies and don't emit energy in all the Planck's spectrum as solids and liquids usually do. Don't stick so strongly to the analogy, though.
123796. chris at 09:16 AM on 22 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        Mike Lockwood has just published a pertinent paper that discusses this subject in detail (along with some interesting comments on Internet-sourced confusion!). I think this paper is freely downloadable: M. Lockwood (2010) Solar change and climate: an update in the light of the current exceptional solar minimum Proc. Roy. Soc. A 466, 303-329 Lockwood Proc Roy Soc 2010
123797. Riccardo at 08:55 AM on 22 February 2010
        On the reliability of the U.S. Surface Temperature Record
        Read this: "But at face value, this plot seems to indicate that the rapid decrease in the number of stations included in the GHCN database in recent years has not caused a spurious warming trend in the Jones dataset — at least not since 1986." It's not on siting issue or UHI, but some people have problems with the decreasing number of stations in the last decades. And the quote does not come from someone from CRU, GISS or other "consensus scientist", it comes from Roy Spencer. I hope that this will slow down a bit some chattering.
123798. carrot eater at 08:29 AM on 22 February 2010
        Is CO2 a pollutant?
        suibhne: It isn't "odd" unless you can clearly state where there is a violation of the First or Second law in the greenhouse theory. G&T claim a violation of the Second Law. If you cannot articulate and defend this violation, then you must abandon G&T. This is now beyond unproductive. We are trying to be patient and polite, but patience is wearing thin.
123799. suibhne at 07:41 AM on 22 February 2010
        Is CO2 a pollutant?
        Philippe Chantreau carrot eater The definition of heat is most important and you will fall into error if you use a "pass with a shove loose definition". That's why I asked you to look up the definitions in a thermodynamics textbook. Where in the Trenberth diagram is there a violation of the Second Law? A above the Stratosphere 342w/m2-agreed? B Just above the Earths surface 390w/m2 up + (168+324)w/m2down = 882w/m2-agreed? You agree, do you not think this is rather odd? This diagram shows that the available energy at surface is almost three times that supplied by the Sun.
123800. Riccardo at 07:31 AM on 22 February 2010
        It's cosmic rays
        Turboblocke, you friend is making some confusion between Mie scattering and Twomey Effect. The latter appears to be interpreted as the explanation of the dependece of clouds albedo on droplet size. I assume this is correct. Twomey (e.g. Twomey 1977, J. Atmos. Sci. 54, 1149) did infact apply Mie scattering (with some aproximations) to clouds and not what your friend said ("greater surface area gives greater 'reflectivity'". What your friend appears to be missing is that as far as clouds are concerned one need to consider that: 1) the total mass of water is kept constant, so smaller drops means larger concentration. 2) in real clouds the droplet size is much larger than the wavelength of light (several microns and more vs rougly half a micron) 3) most of the clouds (low and medium level clouds) are optically thick and therefore single scattering aproximation breaks down. This means that the polar distribution of the scattered intensity varies only slowly, almost flat indeed. This contradicts the claim that "satellites don't measure true albedo". I'd like to add a few other comments on his claims. "models significantly over-predict temperature rise for a given level of CO2 and have to be corrected by an assumed aerosol cooling". Yes, if you give incorrect input to the models you'll get garbage for sure. Indeed, no one denies (i hope) that pollution from aerosol (sulfides in particular) has increased till roughly the '60s. Why the models should not consider this given that they do have an effect on climate? "One paper points out that there is no 'albedo' difference between southern and northern hemispheres when it is known that the aerosol concentration is much higher in the north." This is really a miopic point of view. Is albedo determined just by aerosol? No for sure. You have clouds, oceans, ice and several types of land. It is surprisingly enough that the mean albedo turns out to be almost equal in the two emisphere.

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