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Comments 114351 to 114400:

114351. KR at 03:09 AM on 27 July 2010
        Models are unreliable
        Pete Ridley - I'm still interested in your response to my question on evaluating Hansen 1988 as a scientific model. I believe this is critical to the thread and the discussion.
114352. KR at 02:57 AM on 27 July 2010
        It's waste heat
        RSVP - I see no no numbers in your latest post, no evidence. All you present are "it seems like it should..." statements contradictory to what we observe. The numbers, the measured values, and the physics all say you are incorrect about the importance of waste heat. A hypothesis must be congruent with the evidence. If a hypothesis is contradicted by all the evidence, it's time for a new hypothesis. Waste heat driving global warming just doesn't make sense, RSVP. And you have proved exactly zero evidence to support that hypothesis.
114353. Peter Hogarth at 02:55 AM on 27 July 2010
        Assessing global surface temperature reconstructions
        Ned at 02:04 AM on 27 July, 2010 Thanks, that is indeed a clearer way of visualising the increase. I also forgot to mention I had offset the GISS data in an attempt at clarity.
114354. Peter Hogarth at 02:51 AM on 27 July 2010
        Assessing global surface temperature reconstructions
        Robert Way at 23:14 PM on 26 July, 2010 "ocean trends in the last couple years have not been exceedingly positive" I suspect that was written in haste...? Thermal expansion of oceans in recent years: We have to be careful here. Cazenave 2009 was writing just after the altimeter data was showing a temporary dip in rate of MSL rise, there is something of an update in Cazenave 2010 where the recent estimate of reduction in the thermal expansion component of MSL is put into the context of other previous natural variations (see for example figure 7 in that paper) which look similar and the altimeter trend reverting back to the pre-2007 rate after 2008 (yet table 1 is a repeat of the 2009 one with data up to 2007). This is discussed briefly. There is also new (2010) evidence from Grace on increased land storage of water in Llovel 2010 This first estimate based on measurement of Land storage trend contribution to mean sea level trend is slightly negative, giving -0.22 +/-0.05 mm/year. We then have factors like the 2010 reprocessing of the entire DUACS altimeter data set, though this seems to have reduced variability in global MSL terms (no real difference in estimates of MSL rise rate) it has resulted in some significant (>1mm/yr) localised differences (corrections!) between old and new datasets.
114355. Berényi Péter at 02:50 AM on 27 July 2010
        Assessing global surface temperature reconstructions
        #38 Ned at 00:01 AM on 27 July, 2010 Likewise, there are a lot of people out there who think that the GHCN adjustment process is the cause of the observed warming, and that this warming would disappear if one just went back to the "raw" data. Thus, showing that the warming signal is present in almost identical form in the raw and adjusted data helps dispel that claim. It is not as simple as that. The effect of adjustments on overall GHCN trend may be negligible relative to the raw dataset, but it is not so with USHCN which is a subset of it. On this subset 80% of warming during the lats nine decades is created by adjustments. Also, the statistics of adjustments is entirely different on this subset. This difference in adjustments for the US vs. the rest of the world either does not make any sense from a scientific point of view or it has such a subtle explanation, that it has escaped all the wise people attending to this blog. You can look up the details here and here. An even more serious question is why to waste time and effort to adjustments that have no substantial effect whatsoever on a global scale? It is also shown, that there is not much difference between "rural" and "urban" trends. But no one has explained yet why the far reaching consequences of this observation are ignored.
114356. RSVP at 02:24 AM on 27 July 2010
        It's waste heat
        CBDunkerson #22 "1: Why are temperature increases most pronounced at the poles... where there is virtually no industry generating waste heat? ------------------------------ This gets back to the issue of how N2 and O2 dissipate heat. Not by radiation. Since energy cant be destroyed, it must be spreading itself everywhere. 2: Why do we not see huge spikes of increased heat around urban industrial centers gradually leveling off as you get further into non-industrial regions? ---------------------------- answer to 2.: We do. See links. http://www.epa.gov/heatisld/ http://en.wikipedia.org/wiki/Urban_heat_island http://www.concretethinker.com/Content/ImageLib/lblgraph.jpg 3: Why has warming been most pronounced at night and during Winter? That makes sense if the warming is due to decreases in the rate heat escapes... but not if it is due to increasing 'accumulated heat'. --------------------------- The idea that N2 and O2 are not good emitters of IR agrees with your statement about "decrease in the rate heat escapes". The difference here is in what we assume is causing this. In addition, for a fixed quantity of man-made heat, the lower the temperature, the higher the percentage this represents quantitatively relative to the ambient energy level, and convective heat transfer is in proportion to the difference in temperature. So this also can be applied to answering in part question 1. And I dont know about you, but I personally use more heating oil in the Winter. 4: Why is the stratosphere cooling? Again, that makes sense if heat is being prevented from escaping to the stratosphere... but not if the total heat of the planetary environment is increasing." ----------------------------- Is it really cooling? Obviously this is not based on tree ring data. ;)
114357. Ned at 02:20 AM on 27 July 2010
        It's waste heat
        Yes, CBD, I think that's a useful approach for many topics here. In this case, though, RSVP hasn't offered any empirical evidence in support of his claims for waste heat. Well, I'm a skeptic. I want to see some evidence before I concede that it's even worth discussing.
114358. CBDunkerson at 02:09 AM on 27 July 2010
        It's waste heat
        Ned, many deniers assume that all data which contradicts their beliefs has been faked. Thus it may help to present proofs based on basic logic in addition to those based on data. Or not. Some are impervious to both.
114359. Ned at 02:04 AM on 27 July 2010
        Assessing global surface temperature reconstructions
        Albatross -- thanks! Peter Hogarth: Here's another way of visualizing this: The gray line is RSS (satellite) monthly temperatures through 2000. The pink trendline is the linear trend 1979-2000. Note that, for the past decade, temperatures have mostly been above the pre-2001 trend. In fact, about 2/3 of the months have been above the trend line, including 10 of the past 12. The one exception was the 2008 La Nina.
114360. Berényi Péter at 02:02 AM on 27 July 2010
        The nature of authority
        #133 dcwarrior at 23:57 PM on 26 July, 2010 Perhaps it's time for guest posters from the world of politics, PR or public opinion to give advice on how to turn the tide? No way, man. It is supposed to be a science blog, not a political one. Neither it is a PR device. Read the Comments Policy please. More than one of my comments even slightly touching on political issues got deleted. And I truly wish all such comments have the same fate, even if they came from the other side. In this respect moderation policy is not perfect yet, as there are also posts which have a clearcut political edge, still, they get published here. But it is a shortcoming, not a strength. If you want to turn the tide with such devices, all the authenticity earned so far is thrown into the wind.
114361. Ned at 01:57 AM on 27 July 2010
        The nature of authority
        BP writes: You don't even need a laboratory thermal radiometer to see this. Well, you need either a radiometer or a mathematical model to quantify it. Since he was voicing disbelief in the model, I suggested the radiometer. I do like your visualization though.
114362. Albatross at 01:44 AM on 27 July 2010
        Assessing global surface temperature reconstructions
        Excellent synthesis Ned. Thanks for taking the time and for making the effort. What you have here is a comprehensive summary of the pertinent facts about the global SAT record. I'm not surprised that those in denial about AGW are going to try and dismiss it out of hand-- the data presents a very robust (an inconvenient) picture of warming. Peter @40, you beat me to it :)
114363. Berényi Péter at 01:32 AM on 27 July 2010
        The nature of authority
        #129 AWoL at 10:11 AM on 26 July, 2010 Stefan-Boltzmann says that a squ mtr of material of typical emissivity of 90-95%,at 27degC will beam out something of the order of 459 watts Yes, something like that. A perfect blackbody (e.g. a hole leading to a large cavity) would indeed radiate 459.3 W/m² at 300 K. This 300 K is only 26.85°C, not 27°C, but that's not a big deal. And the hole's emissivity is 100%, not 90-95%. A material of 90% emissivity would radiate 414 W/m² at 27°C. You don't even need a laboratory thermal radiometer to see this. Just imagine a ball of 56.4 cm diameter (surface area 1 m²) filled with 27°C water and left in interstellar space (temperature 2.725 K, that is less than -270°C). If you want to keep its temperature unchanged, it is entirely reasonable that more than 400 W continuous power is needed for heating. Or if interstellar space is too far for you, hang the ball in a large space filled with 0°C thermal radiation. You can apply a thin rope to a branch in a dry winter night with low clouds and temperature around freezing. The background radiation in such an environment is 315.7 W/m² (it is 3.1 μW/m² in interstellar space). In this case, if the emissivity/absorptivity of the ball is 90%, you only need 130 W to keep it at 27°C. Of course you'd need a bit more, because now it is surrounded by (dry) air and it also cools the ball, but heat conductivity of air is low, so in calm weather most of the losses are radiative. If it is still not personal enough, try to calculate how much do you have to eat to stay alive in such an environment naked. The surface of adult human body is about 2 m², skin's emissivity is close to 100% and you should not let your skin temperature go too low, otherwise it dies (gets black and peels off your flesh). Tibetan monks do something like that. It is called tumo and it keeps the body warm in extreme cold. But even they need plenty of tea with yak butter to resupply the energy lost. Fat has 37 kJ/g, therefore 40-50 g butter can supply more than enough heat for an hour for a well trained body. Of course if there is also a chilly wind, more energy is needed, because a lot more air gets into contact with skin, and even if it has low specific heat and low heat conductivity, contact losses can exceed radiative ones.
114364. Peter Hogarth at 01:10 AM on 27 July 2010
        Assessing global surface temperature reconstructions
        Ken Lambert at 23:17 PM on 26 July, 2010 "What is of interest is that there has been a flattening of temperatures since 1998 in all the reconstructions, and overall, the satellite reconstructions since 1975 show less warming than the GHCN charts." I am highly skeptical of this conclusion. I have added the gradients for all three in degrees/year. Now ignoring the fact you cherry pick 1998 which is an obvious peak el Nino year, and the publicly available satellite data goes back to 1978 and not 1975, and the RSS satellite data has indistinguishable gradient from GISS and other land/ocean based datasets since 1978, and the 20 year gradient since 1990 has increased over the thirty year gradient in all data sets, I ask what flattening? or less warming? I could also have added the various independent radiosonde datasets, eg gradient 0.0193 for HadAT since 1990, but no surprises here either.
114365. Ned at 01:07 AM on 27 July 2010
        It's waste heat
        CBDunkerson, those are all interesting questions. For me, though, they're secondary. Being a skeptic by nature, I'd like to see some evidence from RSVP, in the form of a paper or a study or some actual data. Until something like that is presented, why should anyone care about waste heat? Flanner 2009 calculates that it's minuscule, and RSVP hasn't given us any references to contradict that.
114366. CBDunkerson at 00:50 AM on 27 July 2010
        It's waste heat
        RSVP wrote: "I personally dont think humans are better off changing the chemistry of their atmosphere." Sooo... you agree that we shouldn't be emitting all that CO2. Excellent. That said, a few things which need explaining if you want to continue running with this 'global temperature increases are being caused by waste heat' bit; 1: Why are temperature increases most pronounced at the poles... where there is virtually no industry generating waste heat? 2: Why do we not see huge spikes of increased heat around urban industrial centers gradually leveling off as you get further into non-industrial regions? 3: Why has warming been most pronounced at night and during Winter? That makes sense if the warming is due to decreases in the rate heat escapes... but not if it is due to increasing 'accumulated heat'. 4: Why is the stratosphere cooling? Again, that makes sense if heat is being prevented from escaping to the stratosphere... but not if the total heat of the planetary environment is increasing. Those are just a start. There are dozens of other things which clearly indicate that 'waste heat' is not the cause... even setting aside issues of scale.
114367. KR at 00:29 AM on 27 July 2010
        It's waste heat
        RSVP - yep, a glowing fog is all you would see from a satellite at GHG wavelengths. You need to choose a different wavelength (visible, for example) to resolve ground objects. You still have not addressed the base issue of this thread, however. That is the fact that all industrial energy production (waste heat, used energy that eventually becomes heat via entropy, etc.) sums up to a number 2 orders of magnitude smaller than the GHG entrapment of solar energy. If we were to convert all energy production to solar power, with a decrease in Earth albedo, the 1-2% forcing gain in albedo and solar panel waste heat inefficiencies would be more than balanced by the 99% decrease from GHG entrapment. See the RealClimate estimates of energy balance from solar replacement of fossil fuels.
114368. Ned at 00:29 AM on 27 July 2010
        It's waste heat
        RSVP, it would help if you would please give us a reference to a paper or a study that shows that the magnitude of the forcing from waste heat has been dramatically underestimated and that it's comparable to the 2.5 W/m2 from greenhouse gases.
114369. Ned at 00:23 AM on 27 July 2010
        It's waste heat
        RSVP writes: The bulk of the atmosphere is N2 and O2. Most of the heat radiating off of the Earth goes up and out, otherwise we would have temperatures like the hot sidewalk midday. And the heat that goes "up and out" is not included in the stated radiative forcing for CO2. Thus, we can directly compare the radiative forcing from CO2 to the waste heat forcing. As has been pointed out over and over again, the latter is two orders of magnitude smaller than the former.
114370. JMurphy at 00:22 AM on 27 July 2010
        Models are unreliable
        Pete Ridley, I am not a "supporter of The (significant human-made global climate change) Hypothesis" (although I don't know how to react to that rather convoluted and bizarre term - doesn't Anthropogenic Global Warming [AGW] do it for you ?) : I am an accepter of the scientific facts behind AGW. Until I see such facts over-turned, or a better theory come along, I will stick with the AGW one.
114371. adelady at 00:22 AM on 27 July 2010
        Models are unreliable
        Steady on, Pete. You claim there are inconsistencies and inadequacies in the models and argument of "proponents" of AGW. I'd suggest that if you want to maintain consistency with your claim to be a "sceptic" that you avoid expressions like - 'the first UK whitewash hearing'. That seriously undercuts the position you claim to advance.
114372. RSVP at 00:17 AM on 27 July 2010
        It's waste heat
        KR "The only way that energy leaves/cooling occurs via LWR is if the sum of emission events is higher than the sum of absorption events " I assume you are talking about diffusion at some atmospheric boundary layer. However if I was passing overhead on a satellite pointing my IR detector towards the ground, I assume I would "see" IR energy as long as it was "brighter" than this intermediate IR "cloud". In other words, the GHG issue you are talking about is real but subtile, not unlike being able to see fog lights through daytime fog. The point being that if the ground is hot enough, the IR energy will make its way out.
114373. Peter Hogarth at 00:17 AM on 27 July 2010
        Watts Up With That concludes Greenland is not melting without looking at any actual ice mass data
        Berényi Péter at 20:43 PM on 26 July, 2010 Please read the papers rather than jumping in. They cover both your points. Your solution is not most likely. The "missing" heat is not really missing as such but less than the current estimates of uncertainty in factors like TOA radiation. The deep ocean estimates reduce that uncertainty, but as the estimates vary between 5 and up to 20% on recent work we have a way to go before uncertainty is reduced to the point of unambiguous budget balance. In terms of the 0.4W/m2 "missing" I have seen quoted on this thread I note from Palmer 2010 that the interannual variability in net radiation has been estimated as ± 0.7 W m-2 from Wong 2006 whilst Lyman and Johnson 2008 estimated the 2006 Argo coverage in situ sampling uncertainty for the 0-700m layer is approximately ± 0.4 Wm-2 over multi-year time scales at the 95% level, whilst Lyman 2010 slightly increases the estimate of Ocean heating to 0.64 ± 0.11 Wm-2 over the 16 year record at 90% confidence level, and Kawano 2010 may add 5 to 7 % to this. As uncertainties are reduced and estimates revised, we would expect any gaps in error budgets to close. I will be looking at a post on Deep Ocean Heat Content (it will take some time to review the papers). I will also look at any more recent work on net radiation and uncertainties here (I am aware of a few very recent papers).
114374. Ned at 00:16 AM on 27 July 2010
        Assessing global surface temperature reconstructions
        Robert Way, I agree that there's room for some mildly interesting science on the UHI question. I don't think it will turn out to be zero (that would be surprising) but I don't think it will account for more than a small fraction of the observed warming. We know that over the past three decades the oceans have warmed (obviously not due to UHI) and AFAIK every model suggests that the land should be warming faster than the ocean. Those two facts, plus the fact that land is only 29% of the surface, suggest that UHI's impact on the global mean must be fairly small. I think the more interesting science will be on the question of why the tropospheric amplification is not really showing up. If you ignore the land entirely, and just look over the oceans, the lower troposphere should be warming about 1.4X the rate of the surface. We have satellite measurements of sea surface temperature and of lower troposphere temperature. The LT trend is pretty much the same as the SST trend, not 1.4X higher. Both data sets come from satellites. How will this be resolved?
114375. Pete Ridley at 00:07 AM on 27 July 2010
        Models are unreliable
        Jmurphy, you do what supporters of The (significant human-made global climate change) Hypothesis often do, distort what is said. What I said about the first UK whitewash hearing into Climategate and the Met. Office’s decision to stop its long-rage forecasts was “ .. shortly after that that the Met. Office discontinued its long-range forecasts because they were so useless .. ”. That is not the same thing as saying that the decision by the Met Office was a consequence of what was said at the hearing. That should remove one area of assumed disagreement between us. Others, such as the whitewashes, the validity of The Hypothesis and your belief that “code written to represent the Physical qualities of the make-up of potential weather would .. be useful not only for short-term forecasts but also as a basis for long-term climate forecasts”, will be much more difficult to clear up. Best regards, Pete Ridley
114376. RSVP at 00:02 AM on 27 July 2010
        It's waste heat
        CBDunkerson #8 "So... that would suggest that you should support all the changes being suggested by AGW proponents EXCEPT that you should be against nuclear power. Is that the case? " Renewable does not guarantee avoidance of warming. A black solar panel lowers the planet's albedo for instance. This is however getting off topic.
114377. Ned at 00:01 AM on 27 July 2010
        Assessing global surface temperature reconstructions
        Ken Lambert writes: Ned has produced an elaborate snow job. That's a rather unkind thing to say. One of the difficulties of rebutting "skeptic" claims is that they're not uniform. One person claims that there's no warming, another that there's warming but it's from the Sun, and a third that it is anthropogenic but that it will be too small to matter. Inevitably, attempts to answer the claims from person A will lead to complaints from persons B and C that you're ignoring the real point. They may even accuse you of a "snow job" :-) Thus, we see Ken writing: It is no surprise that if you run the same core data through a software processing package - you might get similar results. But that is a surprise to many people. For years, there were all kinds of suggestions that there are problems with the GISTEMP or CRUTEM software. The fact that people wrote different software but get similar results helps dispel those claims about problems with the software. There have also been claims -- including many long arguments on this very website -- that the decrease in numbers of high-latitude stations causes an artificial warming trend. Again, the studies done by people linked in my post dispel those claims. Likewise, there are a lot of people out there who think that the GHCN adjustment process is the cause of the observed warming, and that this warming would disappear if one just went back to the "raw" data. Thus, showing that the warming signal is present in almost identical form in the raw and adjusted data helps dispel that claim. So ... if you never thought there were any problems with the GISS or CRU software, and never believed the widely publicized claims from Joe D'Aleo and Anthony Watts about the "March of the Thermometers" then congratulations. You're way ahead of a lot of your fellow "skeptics", and you can ignore this thread and focus on other arguments. But there are many, many people out there who still have doubts on these points. This thread is for them. Actually, though, you should check out the work by Ron Broberg and Nick Stokes. They've been developing a non-GHCN temperature record, using data from SYNOP reports in the GSOD database. It's quite different from GHCN, though as you can see in Figure 6 above the results are basically the same. Getting back to my point at the start of this comment: Ken, if you think it's a waste of everyone's time for us to be explaining that: * The GISS and CRU software does not introduce "artificial" warming into the temperature record. * The decline in numbers of stations does not introduce "artificial" warming into the temperature record. * The GHCN adjustment process does not introduce "artificial" warming into the temperature record. etc. then there is one constructive thing you can do. Next time one of your fellow "skeptics" makes that argument, you can correct her/him yourself, rather than waiting for me to do it.
114378. dcwarrior at 23:57 PM on 26 July 2010
        The nature of authority
        May I suggest that, given that we know people ARE mistaking the scientific authority that comes from having mastered the subject matter and mistaking it for the bullying kind, that we move on to the next question? I.e., what do we do about it? Sure we can pronounce the problem identified and go on arguing about the minutiae about little parts of the problem. Or, we can ask the people who are used to dealing with that world and see what might work. Note that there are some parents and nannies who are phenomenal at managing even the most intractable kids. There are people who are so good with animals that with a little work they can get even the most hardcore dog to behave. And -- there are political consultants and scientists who do nothing but study and teach politicians and interest groups on how to persuade people of a particular point of view. I submit to you that they are quite good at it. Any thought of drawing on their "mastery" of the subject? After all, the opposition seems to be mostly led by people in that line of work and they are eating your lunch. Re the need to behave as political animals, the great mass of posters on these science blogs and message boards seem to be like the OP who as a kid heard from the older musicians what works and thinking it's all BS. Perhaps it's time for guest posters from the world of politics, PR or public opinion to give advice on how to turn the tide?
114379. KR at 23:56 PM on 26 July 2010
        It's waste heat
        RSVP, if the CO2 molecule re-radiates the IR, the energy leaves with the photon. If not, the CO2 heats up, and hence the air mass does as well. The thing is, given the average path length before absorption for surface pressures and GHG concentrations, the photon will hit another GHG molecule before it's gone very far at all. There are so many chances for absorption that it's not going very far. So that energy will add/subtract repeatedly to the energy of the air mass, and to its temperature. If first you don't succeed, try try again... really expresses this. The only way that energy leaves/cooling occurs via LWR is if the sum of emission events is higher than the sum of absorption events - which happens at the surface (396 W/m^2 going up, 333 W/m^2 going down), between the layers of the atmosphere as it cools with height and absolute GHG concentration drops, and the top of the atmosphere (238.5 W/m^2 LWR going out).
114380. RSVP at 23:49 PM on 26 July 2010
        It's waste heat
        RSVP "The efficiency of energy capture is what matters. " Example... Depending on the material, an object placed in a microwave oven may or maynot get hot. This is how it works.
114381. RSVP at 23:47 PM on 26 July 2010
        It's waste heat
        KR "RSVP - Do you not remember our conversation over GHG's acting as an IR antenna? " I do. :) KR "The source doesn't matter, just the total energy! " I disagree. The efficiency of energy capture is what matters.
114382. RSVP at 23:44 PM on 26 July 2010
        It's waste heat
        Ned "All of your arguments about waste heat accumulating in the atmosphere apply in exactly the same way to heat from GHG forcings. The only difference is that GHGs produce vastly more heat. " The bulk of the atmosphere is N2 and O2. Most of the heat radiating off of the Earth goes up and out, otherwise we would have temperatures like the hot sidewalk midday. If a photon happens to excite a CO2 molecule, this energy may or may not make it to a nearby N2 or O2 molecule. All this describes a not so efficient heat capturing system. Nearly all the heat passing over a heat engine elevates the temperature of N2 and O2 directly (through convection). These gases in turn are not good emitters of radiation.
114383. KR at 23:44 PM on 26 July 2010
        It's waste heat
        RSVP - Do you not remember our conversation over GHG's acting as an IR antenna? Energy goes into the atmosphere (conduction/convection from your automobile radiator, household AC, LWR from the ground. The air mass from this energy acquires a certain temperature. The source doesn't matter, just the total energy! GHG's radiate over their thermal spectrum based upon the temperature of the air mass. The 'waste heat' (mis)issue is that total industrial waste heat is 2 orders of magnitude smaller than the GHG forcing, the extra solar energy held by greenhouse gas increases. Those are the numbers, RSVP, waste heat is only 1% of the problem, hence nobody is really worried about it.
114384. RSVP at 23:28 PM on 26 July 2010
        It's waste heat
        CBDunkerson at 23:01 PM on 26 July, 2010 "What then should the proper course of action be?" I personally dont think humans are better off changing the chemistry of their atmosphere. And the challeges are huge. As such, we better get our ps and qs straight. There is no guarantee that the ill effects of global warming are going to be sufficient to stop fossil fuel burning. It might even be the biggest straw man to justify continuing to do so. If on the otherhand it turns out that higher CO2 levels has profound ill effects on the biosphere (for who knows what reasons), then that is where the science and effort should be dedicated.
114385. Ned at 23:27 PM on 26 July 2010
        It's waste heat
        RSVP, the radiative forcing from CO2 (and other GHGs) only includes the outgoing longwave radiation that is actually trapped within the atmosphere. It doesn't need to "get to the atmosphere"; it occurs within the atmosphere. All of your arguments about waste heat accumulating in the atmosphere apply in exactly the same way to heat from GHG forcings. The only difference is that GHGs produce vastly more heat.
114386. RSVP at 23:20 PM on 26 July 2010
        It's waste heat
        "Ned at 21:38 PM on 26 July, 2010 RSVP, there's no difference between heat that enters the atmosphere via radiative absorption and heat that enters the atmosphere as waste heat. " I agree. Heat is heat. However how it gets to the atmosphere is different. Internal combustion engines for instance are very efficient in the way they employ convection to rid themselves of excess energy. The car's radiator heats N2 and O2 directly, pushing cool air over a large surface areas. Heat that accumulates on a boulder during the day on the contrary, cools for the most part via radiation. Most all of that energy makes its way into outer space. If this was not true, the Earth would not maintain its temperature equilibrium. The AGW theory precisely points to anthropogenic CO2 as improving the "efficiency" of the atmosphere in capturing this radiated energy, even though most of this energy passes through like a sieve (i.e. the atmosphere is IR opaque in relation to "GHG" concentration.) Another way to explain this... If CO2 heat capturing efficiency is 5% (I am making this up for sake of the discussion, and referring to the efficiency of CO2 to pick up heat that warms the air), as compared 90% efficiency of convective heating of say an air conditioner. If I have 100 joules, in the first case, I am only going to warm the atmosphere by 5 joules, whereas with my air conditioner it will leave 90 joules.
114387. Ken Lambert at 23:17 PM on 26 July 2010
        Assessing global surface temperature reconstructions
        Ned has produced an elaborate snow job. It reads like these are truly 'independent' sources of data. The critical piece of information regarding NASA, CRU and NOAA reconstructions is this: Quote: "All three have at their core the monthly temperature data from the Global Historical Climatology Network (GHCN), and all three produce both a land-stations-only reconstruction and a combined land/ocean reconstruction that includes sea surface temperature measurements." Endquote It is no surprise that if you run the same core data through a software processing package - you might get similar results. The only 'independent' sources of temperature data are the satellite data from RSS and UAH. I believe these draw from the same satellites. Again it is no surprise that they produce similar results to each other. What is of interest is that there has been a flattening of temperatures since 1998 in all the reconstructions, and overall, the satellite reconstructions since 1975 show less warming than the GHCN charts. Of even more interest is that theoretical CO2GHG forcings have been at their highest levels and steadily increasing over that period with increasing CO2 concentrations in the atmosphere. The surprise conclusion of this article: "The well-known and widely-cited reconstructions of global temperature, produced by NASA GISS, UEA CRU, and NOAA NCDC, are replicable." I should jolly well hope so - otherwise why are we in this monumental debate over the nature and extent of global warming!!
        Response: "there has been a flattening of temperatures since 1998"
        
        This line of thinking has been examined in detail in a recent blog post.
        
        "satellite reconstructions since 1975 show less warming than the GHCN charts"
        
        The UAH satellite trend is slightly less than the GHCN trends but the RSS satellite trend is nearly identical to the GHCN trends. The reason for the difference between UAH and RSS is examined here.
        
114388. robert way at 23:14 PM on 26 July 2010
        Assessing global surface temperature reconstructions
        muoncounter, #21: "urban heat island effect" Where have we heard this before?...etc... Firstly, I'm not a conspiracy theorist. The many people who are included in this post as being independent researchers are all focused on this issue as being the next important one to solve. I believe that the conclusion that the UHI effect is negligible is not an effective way of looking at this issue. We do know that warming is occurring right now Globally but just because we are on the side of the consensus does not mean that we should leave some issues unresolved. And about the ocean temperatures, lets be real, ocean trends in the last couple years have not been exceedingly positive. The warming could perhaps be stored somewhere else (deep ocean maybe?)but it is clear to see that the thermal expansion of the oceans has reduced compared to during the late 1990s. Even Cazenave et al. 2009 conclude that.
114389. CBDunkerson at 23:01 PM on 26 July 2010
        It's waste heat
        RSVP, let's for the moment assume that the 'waste heat' argument isn't complete nonsense. Temperatures are still rising at the same rate. Humans are still causing it (i.e. it is still "AGW"). Fossil fuel use is still the source. What then should the proper course of action be? Under this view the rising temperatures which have been observed are due to the buildup of heat from burning fossil fuels over time. Does this not argue for converting from fossil fuels to renewables like solar and wind? The only significant difference is that nuclear power is out as an alternative because it is just as much a 'waste heat' generator as fossil fuels. So... that would suggest that you should support all the changes being suggested by AGW proponents EXCEPT that you should be against nuclear power. Is that the case?
114390. Ned at 22:36 PM on 26 July 2010
        It's waste heat
        Sorry, johnd, but that's not particularly logical. Re your first statement, one could imagine a scenario where waste heat was contributing a huge warming forcing, but it was being countered by an even larger cooling forcing. The fact that the (imaginary) planet was cooling overall wouldn't negate the actual warming effect of waste heat. Re your second statement, the candles on my dining room table must "contribute" to warming the global atmosphere, too. But not in any meaningful amount! This is why it's important to quantify forcings, which is exactly what Doug Bostrom does in his comment upthread. Globally, waste heat is two orders of magnitude below greenhouse gases in its importance. Saying that non-quantitatively it must "contribute" is pretty much useless.
114391. johnd at 22:26 PM on 26 July 2010
        It's waste heat
        RSVP at 19:53 PM, to determine whether or not waste heat is accumulating and contributing to global warming, it's only necessary to go back to the very basics. If the rate at which the planet is warming is less than that which waste heat adds, then NO, waste heat possibly does not contribute to the global warming and is dissipated. However, if the rate of global warming is greater than that which waste heat adds, then YES waste heat must both contribute, and continually accumulate year upon year.
114392. JMurphy at 22:15 PM on 26 July 2010
        Models are unreliable
        Pete Ridley, if you wish to believe that the 'Climategate' enquiries are all "whitewashes", and that the "scandal" still remains (albeit only in the minds of those who don't wish to face up to the facts), then I cannot write anything that will get through to you : you only see what you want to see. I will, though, disagree with you with regard to the Met Office's Seasonal Forecasts - they had obviously already decided to scrap them before announcing so on March 5, so I doubt whether the House of Commons enquiry had anything to do with it. You, no doubt, would disagree, but, again, you must believe what you want to believe. In the same way, you believe those Seasonal Forecasts were "useless", so, again, nothing I write would be able to change your mind. To end, code written to represent the Physical qualities of the make-up of potential weather would, I would imagine, be useful not only for short-term forecasts but also as a basis for long-term climate forecasts.
114393. Ned at 21:44 PM on 26 July 2010
        Assessing global surface temperature reconstructions
        werecow writes: Very nice post! Just out of curiosity, what was the reason for the large size of the 2008 GHCN adjustment? I don't know. However, I do find it mildly amusing that certain people make aggressive claims about the GHCN adjustment process when the actual effect of the adjustment is to reduce the magnitude of the post-1970s warming trend. I haven't done a survey, but I would bet that a very large percentage of the WUWT readership assumes that the GHCN adjustments artificially inflate warming, when in truth they add a (very small) cooling trend in recent decades.
114394. Ned at 21:38 PM on 26 July 2010
        It's waste heat
        RSVP, there's no difference between heat that enters the atmosphere via radiative absorption and heat that enters the atmosphere as waste heat. It's not that one "accumulates" and the other doesn't. It's just that, globally averaged, the quantity of watts from waste heat is much smaller than the quantity of watts from absorption by GHGs. Doug kindly provides the numbers in his comment before yours. Globally, waste heat is roughly two orders of magnitude below the sum of CO2, CH4, N2O, and halocarbons. It's not zero, but it's negligible.
114395. Ned at 21:27 PM on 26 July 2010
        The nature of authority
        AWoL, "night vision equipment" is not the way to measure thermal radiative flux. You want a laboratory thermal radiometer, and with one you will verify that yes, S-B is correct. Frankly, I have to admit I'm astonished by what I see on this website right now. In another thread RSVP is questioning basic laboratory measurements of the spectral properties of gases that have been known since the 1850s. In this thread, AWoL is rubbishing the Stefan-Bolzmann constant, which was first measured in the 1880s (?). That is not skepticism. When something has been measured and applied by scientists and engineers for over a century, and is the building block for a great deal of subsequent science and technology, a skeptic demands very strong evidence to overturn it. As far as I'm concerned, if you come on this site and want to claim that Stefan-Bolzmann is wrong, or Maxwell's equations are wrong, or CO2 does not absorb longwave radiation, you need to present a detailed and explicit case that lays out exactly how and why every physicist who's worked in this field since Tyndall has been mistaken. You need to specify exactly what the problem is. Don't just waste everyone's time by tossing out ill-formed ideas or crackpot hypotheses. And of course, if you can disprove basic tenets of radiative physics, you shouldn't be wasting your own time doing it here. Write it up and submit it to Science or Nature. You will be famous, and future generations of scientists and engineers will be eternally grateful to you. Until you do that, though, posting claims here that a century's worth of physics or chemistry is wrong will inevitably tar you with the label of crackpot. And nobody wants to see this site get mired in crackpottery.
114396. tobyjoyce at 20:54 PM on 26 July 2010
        Assessing global surface temperature reconstructions
        @chriscanaris, Your opinions on WUWT do not correspond to mine. To me, it is a political rather than a science website. If you think of its readers as a "constituency" they are offered almost continual reassurance from the posters of the rectitiude of their position, that victory is assured, that reason in on their side, and that the opposition are fraudulent posers who are about to be found out. The multiple ironies are obvious, particularly in the regular accusation that climate science is a "religion", but also obvious is the resemblance to politicians interacting with their followers. Most of the threads, while obstensibly "science" or science-related, seem to be shaped with this in mind. As true science, they do not stand up to scrutiny. Most of the science projects initiated by WUWT seem to have run into the sand ... at least I have not heard much about them recently. "Citizen science" that it claims to be pushing has not much to show. Of course, many websites on the pro-side, fall into the same bracket, but are not a strident as WUWT, and have much more science to boot. But then, many of those bloggers are already professional scientists with a day job.
114397. Berényi Péter at 20:43 PM on 26 July 2010
        Watts Up With That concludes Greenland is not melting without looking at any actual ice mass data
        #56 Peter Hogarth at 18:59 PM on 16 July, 2010 On the idea that overturning rates and hypothesised lack of vertical mixing to deep layers means it take centuries to change bottom water temperatures, there is a significant amount of measured evidence that suggests otherwise. That's good news. At least we don't have to worry over ocean acidification. However, even if heat (and dissolved carbon dioxide) have an easy way to the abyss, it does not solve the problem at hand. If the bulk of Trenberth's missing heat went that deep, it would have produced more steric sea level rise than observed, as 1. for layers of equal thickness the deeper you go the less mass you have due to bathymetric constraints 2. volumetric thermal expansion coefficient of seawater increases with pressure The most likely solution is the missing heat simply went to the coldest and largest heat reservoir around, to outer space at a temperature of -270.425°C (-454.765ºF). That is, it was not trapped at all.
114398. RSVP at 20:17 PM on 26 July 2010
        It's waste heat
        RSVP errata (a) but for all practical purposes, energy that enters the atmosphere IN THIS WAY stays here on Earth. (b) can only deliver heat by convection to cooler places (i.e., global warming).
114399. RSVP at 20:05 PM on 26 July 2010
        Rebutting skeptic arguments in a single line
        I have made my entry at the specified link. http://www.skepticalscience.com/waste-heat-global-warming.htm I did not see this included in the grand skeptic list, but on the other hand, I didnt see an entry for CO2 being the main cause either.
114400. RSVP at 19:53 PM on 26 July 2010
        It's waste heat
        The central concern of man-made CO2 emissions has to do with its IR absorptive qualities, and for this reason it is referred to as a "greenhouse gas". Given that CO2 represents a very small percentage of the Earth's atmosphere, and in respect to the particular concerns, the implication is that its efficiency to radiate and absorb IR must contrast substantially with that of N2 and O2. The effect of greenhouse gas warming has to do with final results, such as the melting of polar caps and glaciers, and the warming of ocean water and land as well as the N2 and O2 that make up 97% of the Earth's atmosphere (i.e. climate change). Exothermic man-made industrial waste heat involves IR emission, but most of this heat consists of direct convective heating of both water and air. The idea that a significant portion of global warming could be attributed to industrial waste heat resides in the question of how N2 and O2 dissipate heat when its temperature is elevated beyond mechanisms that are normally found in Nature. While N2 and O2 (the bulk of the Earth's atmosphere) are not the best radiators at nominal atmospheric temperatures, they do cool nicely convecting to cooler water and ice, so as to provide a heat channel from one's home or automobile directly to oceans, glaciers and polar caps. On the other hand, it can be assumed this system is lossy to some degree in that CO2 picks up some of this energy and sends it upward to the heavens, but for all practical purposes, energy that enters the atmosphere stays here on Earth. For however small this energy may be, if it is accumulating, we should begin to notice it as something that is building slowly (i.e., hocky stick graph). And addressing those that dismiss waste heat on arguments based on numerics, it is not a matter of comparing a figure of forcing per square meter if this heat is not efficiently involved with radiative processes. In other words, if N2 and O2 are not GHGs they can only deliver heat by convection to cooler places.

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