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Doug Bostrom at 01:34 AM on 28 July 2010Waste heat vs greenhouse warming
TOP, there is only one difference in the grand scheme of things as viewed from the top of the atmosphere between a warm rock and a warm IC engine. The rock was warmed by insolation, the engine by liberation of energy stored in fossil fuels. Heat liberated by whatever means and no matter how many times the energy of that heat is bounced from hand-to-hand remains ideologically sterile from the perspective of how it escapes Earth. Remove the engine from your car. Warm a boulder of similar mass in the sun. Place it in the engine compartment of your car. Close the hood. Does the warmth emerging from the car by a combination of conduction and radiation know where it came from? Does it behave in a special way? Are joules endowed with a sense of history? This is a rather mind-blowing discussion! -
Ned at 01:33 AM on 28 July 2010Waste heat vs greenhouse warming
I should probably revise the analogy I used above. Apparently, a slice of whole-wheat toast has about 80 kcal. To make the analogy apt, I would have to be eating somewhere around 8000 kcal of ice cream per day. I don't think that would be possible. So, to keep the quantitative proportions correct, let's say we're trying to determine whether my weight gain is due to the daily 2 cups of ice cream or the one-eighth of a slice of unbuttered toast. I think that gives the appropriate two orders of magnitude difference. So, what RSVP is saying is basically "Don't worry about eating that pint of Ben & Jerry's ... it's that one bite of toast that's making you gain weight." -
AWoL at 01:20 AM on 28 July 2010The nature of authority
Thanks for the reply Ned. Here's a couple of items, that led me to question the Stefan Boltzmann Law and Constant "1)Published online on May 24, 2010, the study argues that the flaw has always lain in Stefan-Boltzmann's equations. The long-trusted formula has been used by climatologists without question - until now. The researchers report that the numbers used in those equations are the “first assumption that climate science makes when predicting the Earth's temperature.” NASA Abandoned Flawed Climate Calculations in 1960’s Read more at Suite101: Apollo Mission: A Giant Leap Contradicting Greenhouse Gas Theory http://climatology.suite101.com/article.cfm/apollo-mission-a-giant-leap-to-discredit-greenhouse-gas-theory#ixzz0uoPWUQBV 2)Teaching Labs...dept of Physics and astronomy...Dartmouth College The Stefan-Boltzmann law states that for a blackbody the exponent should be 4. The student sees that for low temperatures the exponent is as low as 2.5 and for higher temperatures (approximately 1800K) the exponent lies in the range of 3.6-3.9. What I'm after is examples, and confirmation, of S-B at temperatures in earthly materials in the range of -40to100 degC as the titles of those two papers would suggest. 1)Deviations from the S-B Law at low temperatures, by HP Baltes,Universtat Berlin cost$34. 2)A Radiometric Determination of the S-B Constant and Thermodynamic Temperatures between -40degC and 100degC, Quinn and Martin, Nat Phys Lab, Teddington , Middlesex.Cost unknown and don't care as I ain't paying. Most of the information concerns incandescent filaments of 1000degC or other such unworldly situations. It looks as though there is little wrong with SB at earthly temperatures. The problems seem to come with assumptions built into application in the real world, such as happened on the moon.... and this method for deriving radiative flux arriving at the earth's surface. "The earth absorbs radiation as a disc...pi.r^2 but radiates it as a sphere....4.pi.r^2.....so just divide the incoming flux by 4". Yet the area irradiated is 2.pi.r^2.Is that a reasonable assumption? Maybe to a physicist, but not to a layman. And the sphere should be rotating. What effect would that have? Has anyone checked this out? Does theory match practice? Sorry for taking up space in exploring those fundamentals. Maybe there should be a "dummies section".I just don't see how one can form a reasonable opinion of AGW, without checking on the fundamental physics first......the actual measured results , here on Earth and not an extrapolation (which may or may not be accurate) from theory and highly controlled and unusual situations ie incandescent tungsten filaments, in the laboratory. -
CBDunkerson at 01:17 AM on 28 July 2010Waste heat vs greenhouse warming
dcwarrior, no it isn't the same thing at all. We're dealing with two different examples of pure denial; In the first case the claim is that a small percentage cannot have a big impact (e.g. CO2 as a small percentage of the atmosphere cannot cause warming, brakes as a small percentage of a car's mass cannot cause the vehicle to slow down). In the second case the claim is that a small percentage coming from source A is more important than a large percentage coming from source B (e.g. global warming is being caused by the 1% 'waste heat' NOT the 99% of additional heat from GHGs, air friction slows a car 1% as much as brakes do... therefor it is air friction stopping the car, not the brakes). Yes, heat from human industry can be a somewhat significant issue on local scales. It is the second most significant cause of the 'urban heat island' effect... but even there most of the localized heating is from land use changes. On a global scale we would need to burn vastly more fossil fuels than we currently do (indeed, vastly more than EXIST on the planet) in order for industrial heat to be an issue. If we converted fully to nuclear power then maybe in a few hundred years it would start to be significant... but far more likely we'll convert to mostly wind and solar power (which don't release any 'extra' energy that had been stored). -
dcwarrior at 00:50 AM on 28 July 2010Waste heat vs greenhouse warming
I think one lay question that needs to be answered is this: "OK, the deniers are telling me that CO2 is only a tiny % of the atmosphere so how could any change in that possibly affect the global temperature. And they go on to say that human caused CO2 is small in relation to that. And, OK, I've seen your explanation as to why this is not so, that humans are adding to the CO2 and that it's a greenhouse gas, I get it. So, seeing as how the human caused warming is only a small % of the total earth warming, isn't that the same thing?" Also, isn't heat pollution an issue that is a problem in some localities (like near nuclear plants) and may actually become a global problem someday? -
dcwarrior at 00:43 AM on 28 July 2010The nature of authority
#136 Berényi Péter at 02:02 AM on 27 July, 2010 >> My point is that the writing on here seems very technical and if I may say so, not very persuasive. I understand it's a science blog but it is also a blog that is trying to persuade deniers that climate change is real. Being better at understanding what arguments (supported by science) are more effective at persuading people is "political" but not in the way that the comments policy prohibits. And unless "authenticity" means discussing only technical issues with no hope of convincing anyone of anything, I don't think coming up with focused arguments that better present the science and address the underlying concerns of the deniers would lack authenticity. -
Magnus W at 00:33 AM on 28 July 2010Waste heat vs greenhouse warming
Do not miss my favourite on the subject... who actually managed to publish on the subject in a journal... http://westerstrand.blogspot.com/2008/09/its-that-time-of-year.html -
Ned at 00:21 AM on 28 July 2010The nature of authority
Provided of course claims hard to verify and based on scant data are preferred to easy and well documented ones. That would be a reasonable assessment of my comment ... Provided of course that illogical and unfriendly interpretations are preferred to simple and straightforward ones! :-) -
Berényi Péter at 00:15 AM on 28 July 2010The nature of authority
#147 Ned at 22:46 PM on 27 July, 2010 it might be helpful to look at the entire 0-20 N region, rather than individual points Definitely. Provided of course claims hard to verify and based on scant data are preferred to easy and well documented ones. It is Colaba Woods, Mumbai, India (18.9 N, 72.8 E).
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TOP at 23:56 PM on 27 July 2010CO2 is not a pollutant
ScienceDaily (May 9, 2003) states that higher levels of CO2 may allow forests to grow in arid areas that once were unsupportive of trees. This information comes from studies in the Negev, one of the driest places on earth. "Plants need carbon dioxide for photosynthesis, which leads to the production of sugars. But to obtain it, they must open pores in their leaves and consequently lose large quantities of water to evaporation. The plant must decide which it needs more: water or carbon dioxide. Yakir suggests that the 30 percent increase of atmospheric carbon dioxide since the start of the industrial revolution eases the plant’s dilemma. Under such conditions, the plant doesn’t have to fully open the pores for carbon dioxide to seep in – a relatively small opening is sufficient. Consequently, less water escapes the plant’s pores. This efficient water preservation technique keeps moisture in the ground, allowing forests to grow in areas that previously were too dry." In fact one proposal suggests that all the world's industrial release of CO2 could be absorbed by planting trees in the deserts of the world and in particular the Sahara. Haaretz Tue, July 27, 2010 Israeli ecologists could help stop global warming. -
Arkadiusz Semczyszak at 23:54 PM on 27 July 2010Waste heat vs greenhouse warming
“But there is no difference in the heat from different sources.” Really? Let's see: “... but over the continental United States and WESTERN EUROPE, it is +0.39 and +0.68 W m−2, respectively.” To be "showy" suggesting a temperature records from the U.S. - the warmest 10 years: 1934-1998 (1.24), 2006, 1921, 1931, 1999, 1953, 1990, 1938, 1939/54/87/2007 (0.84) , and: NH (24-90 N), the warmest 10 years: 2007 (1.09), 2005, 2006, 2003, 2002, 1998/2001, 2004, 1999, 2000 (0.68) ... Let's see where those records (2006/7) have occurred in the NH - WESTERN EUROPE: http://www.wiz.pl/obrazki/rekordowe_09_08.jpg (Mean temperatures of subsequent 12 months in 2006/2007 higher than ever in the history of obserwations - source: Climate change and extreme event ..., Kundzewicz, 2008, page 7), very carefully (extremely carefully !) areas with a record temperature of overlap areas of greatest heat production (industrial centers, large urban agglomerations). This is particularly evident in the example: Italy, Spain, Great Britain, Portugal, South France, Scandinavia ... Once again it is worth recalling: de Laat, ATJ, 2008: "Current Climate Impact of Heating from Energy Usage: The global average primary energy consumption (0.03 watts per square meter) is relatively small compared to other anthropogenic radiative forcings, as summarized in the recent Intergovernmental Panel on Climate Change report. NEVERTHELESS, despite its RELATIVELY SMALL magnitude, waste heat may have a CONSIDERABLE IMPACT on local surface temperature measurements ...”, “On a city scale, such as central New York or Tokyo, energy use can exceed 100 watts [!] per square meter [Makar et al., 2006].” , “… Block et al. [2004] used a regional climate model to investigate the magnitude of warming in WESTERN EUROPE caused by adding 2 watts per square meter of energy at the model land surface. Although the model simulation was performed for just 3 months during spring, the results nevertheless indicate that warming does occur, and—under FAVORABLE CONDITIONS—it can on average be as large as 1°C [...] for the 2 watts per square meter surface forcing.” “In addition, the spatial inhomogeneous distribution of the waste heat effect may actually have a much larger impact on local and regional [!] atmospheric circulation than what could be expected based on their global average. This impact can be larger than the local to regional impact of well-mixed greenhouse gases [ Matsui and Pielke , 2007].” “There is some observational evidence that waste heat has changed temperatures not only locally but also regionally [!!!]. Several recent papers [ de Laat and Maurellis , 2006 and references therein; McKitrick and Michaels , 2007 and references therein] suggest that a link exists between observed warming patterns and industrialization or urbanization. For example, there is considerably more surface than free tropospheric warming in the EASTERN UNITED STATES, suggesting the presence of a surface warming process [ Kalnay et al. , 2006; and references therein].” “FAVORABLE CONDITIONS” - remember that the areas of heat production there is often a strong local greenhouse effect (ozone, water vapor), much of it more efficient mechanical thermal insulation: smog - chemical and photo-chemical, standing for many days urban and industrial areas of high pressure, nocturnal boundary layers (NBL), etc., etc., Real Climate, T. Rogers, 30 october 2009: “My interest was to compare the possible effect of waste heat on the temeperature of urban areas. To do this I made some (wild!?) assumptions that 50% of the world population lived in urban areas but 90% of waste heat was released in urban areas (power stations, industry and residential vs residential/low tech in rural areas). I used world population and a an estimate of urban population density to calculate an estimate for the area of the earth’s surface that was “urban”. Using this method I obtained figures for waste heat in urban areas of 7.7 W/m^2 in 1900 and 20.6 W/m^ in 2000. [!!!] THESE SEEMED LIKE FAIRLY SIGNIFICANT NUMBERS TO ME.” -
Ned at 23:54 PM on 27 July 2010Waste heat vs greenhouse warming
Ken points out that a 2.9 W/m2 forcing from greenhouse gases doesn't represent the full picture, since there are other negative (and positive) forcings and feedbacks. John Cook nicely summarizes these different forcings and feedbacks here: CO2 is not the only driver of climate However, introducing the other factors obscures rather than clarifies the role of greenhouse gases. Let's consider my body mass as an analogy for the atmosphere. I'd like to keep it in equilibrium! There are a mix of positive and negative forcings (basically, eating tasty stuff makes me gain weight, while exercising makes me lose weight). Let's say I'm both eating a lot and putting a lot of time into exercising, but the former outweighs (ha!) the latter, so my weight is slowly increasing at 3 kg per year. If the question is "how far out of equilibrium is my body's mass balance" then we need to look at all the positive and negative drivers. But if the question is "which is responsible for my weight gain, the toast I have for breakfast or the heaping bowls of ice cream I have after lunch and dinner" then we just want to compare the magnitudes of those two individual forcings. In case the analogy isn't clear, in this case the toast represents the waste heat and the bowls of ice cream represent the greenhouse gases... :-) -
KR at 23:40 PM on 27 July 2010Waste heat vs greenhouse warming
TOP, RSVP, others - regarding sources of heat energy and it's distribution: Heat can enter the atmosphere via convection, latent heat, conduction, and radiation. Convection from a radiator or a hot rock (that doesn't radiate at IR wavelengths, an odd statement considering the data I found here on rock-forming minerals) warms the immediate area, while IR radiation tends to get absorbed within the first 10 to 100 meters. But all of the energy will get absorbed, at least until it has a chance to go somewhere else. After that, the source of the energy does not matter. The temperature of the air goes up. the 10^9 collisions/second/molecule distribute the energy to all molecules in the air mass, whether O2, N2, CO2, CH4, Ar, whatever. Energy has been added to the system. At atmospheric temperatures, CO2 and other greenhouse gases will radiate energy. Tropospheric convection will occur. Water vapor will circulate, with evaporation and rain moving energy around. And eventually, that energy will radiate from the top of the atmosphere as longwave infrared radiation. But there is no difference in the heat from different sources. A joule is a joule, a photon is a photon, and unlike Arizonans, they don't carry ID cards indicating where they are from. And given that industrial energy usage is 1% that of GHG entrapment, industrial heat isn't an issue at this time. -
Ned at 23:36 PM on 27 July 2010Waste heat vs greenhouse warming
TOP, your points 2, 3, and 4 are actually part of why waste heat is so directly comparable to the radiative forcing from GHGs. Doug's large boulder loses some heat by radiation and some by conduction into the ground. Waste heat from our various mechanical machinations is proportionately more likely to go directly to the atmosphere. Likewise, the warming from GHGs occurs directly within the atmosphere. TOP and RSVP seem hung up on the idea of the surface losing heat via radiation ... but the warming that occurs, and the 2.9 W/m2 forcing, is the absorption of radiation within in the atmosphere. All of the 2.9 W/m2 are transferred to the atmosphere, and once there, they behave exactly like the 0.028 W/m2 from waste heat once it gets in the atmosphere. The origins of the two sources are different, but once they're in the atmosphere, they behave identically. The only difference is that 2.9 W/m2 is two orders of magnitude greater than 0.028 W/m2. -
Ken Lambert at 23:35 PM on 27 July 2010Waste heat vs greenhouse warming
John Cook, (original post) John Cook and Gentlemen: Your 'Greenhouse Warming' of 2.9W/sq.m is only half the story. The good Dr Trenberth has shown us that the net TOA imbalance by his calculation is in fact 0.9W/sq.m when cloud, aerosols, albedo, feebacks and radiative cooling are taken into account. So the Earth is not warming at 2.9W/sq.m -- rather more like 0.9W/sq.m. As we know also - as of Aug09 - he could only find about 0.55W/sq.m in land and OHC. As for waste heat; here is a more interesting sum: Globally the rate of 0.028W/sq.m gets much bigger if you reduce the sq.m from which nearly all of it emanates. Not much human industry or population on the oceans (71%) or the Arctic and Antarctic, or the vast deserts or steppes. I believe only about 6-8% of the global surface is producing this human/industrial waste heat. Some will be much more concentrated around urban and highly industrialized centres. So 0.028 divided by say 0.07 (7% of the global surface) becomes 0.4W/sq.m heat flux over these inhabited areas. A figure of 0.3-0.5W/sq.m has been quoted for the continental USA. This is not small in comparison to the purported TOA imbalance of 0.9W/sq.m. for those areas (which are also on the globe). So UHI effects being concentrated further and general effects over industrial populations should have a significant effect on land temperatures in that 6-8% of the global surface. Of course BP and others have fought out the UHI vs population density relationships elsewhere, but the issue of how much of the 6-8% of the global surface accounts for all the GHCN core data records is a live one for those more expert than me. -
Rob Painting at 23:30 PM on 27 July 2010Waste heat vs greenhouse warming
TOP - "Since either form of removal results in an increase in the green house gas H2O there is another forcing resulting from this form of waste heat." Are you saying, what you seem to be saying?. -
Ned at 23:26 PM on 27 July 2010Assessing global surface temperature reconstructions
Thanks, Ken. A few comments on your comments about my comments.... My criticism centres around the notion that three analyses of the same core data somehow adds validity to the basic core data. Again, keep in mind that we have to start with baby steps here. There are people who think the software to produce these reconstructions is secret and the results can't be replicated. There are people who think that decreasing the numbers of high-latitude stations is artificially warming the record. There are people who think that the GHCN adjustment process is somehow implicated. None of these are true, so it's helpful to establish that. I agree that going further requires looking at other data sets besides GHCN. Of course we have satellite data on sea surface temperatures and lower troposphere temperatures, so that's helpful. It would also be helpful to have another land temperature record not based on GHCN -- that's what Ron Broberg and Nick Stokes have been working on. Anyway, there seems to be a lot of evidence in support of the existing surface temperature reconstructions. After spending all this time researching them, I now feel pretty confident. Nobody seems to be able to come up with a reconstruction that's radically different. Ken continues: It is most probable that a temperature trend is non-linear in any case. Yes, I agree, though I'd politely differ a bit from your explanation of this. CO2 doesn't depart a lot from a linear trend over short (1-2 decade) time scales, and I think the solar contribution is pretty small (it's been declining over the past few decades but temperatures have been high since 2000). I think most of the nonlinearity comes from internal processes related to the movement of heat within the climate system (e.g., ENSO). That's a difficult thing to model, so looking at short time periods (sub-decadal) is problematic. My personal opinion about the "flattening" is that it's an artifact of the very rapid jump in temperatures at the start of the decade (2000-2002) plus a large La Nina near the end (2008). If you refer back to my figure from a previous comment temperatures have persisted at a high level. A substantial La Nina in 2008 only temporarily brought us down to temperatures that were ordinary back in the mid-90s, and a relatively small El Nino now produces temperatures that rival the peak from the monster El Nino of 1998. So I think the "flattening" thing will ultimately turn out to be an artifact of people over-interpreting the noise in the signal. -
TOP at 23:17 PM on 27 July 2010Waste heat vs greenhouse warming
doug_bostrum Any difference between a warm rock and a warm engine, thermally speaking, RSVP? Yes. 1. Depending on the temperature of the warm rock, the heat may or may not be captured by CO2 since CO2 has a very narrow band in the IR where it will capture heat and the IR band in which the hot rock radiates changes with temperature. H2O in the atmosphere has a much higher chance of capturing the hot rocks IR radiation. Think of the desert where the temperature falls like a rock when the sun goes down (pun intended). Desert areas are a good indicator of the effect of GHG because there is little effect from H2O acting as a GHG. 2. A hot engine is shielded from radiating directly to space by an insulated sheet metal shield (the vehicles body). Therefore the heat loss of the engine is primarily through conduction to the air and then convection. 3. Waste heat from a power plant is generally carried away by a cooling tower or placed into a water body. In either case it transfers heat to the atmosphere by either convection or phase change. Since either form of removal results in an increase in the green house gas H2O there is another forcing resulting from this form of waste heat. 4. Waste heat from the use of energy is primarily put back into the atmosphere by means of convection (think the heat coming from your monitor and cooling fan as you read this post). -
CBDunkerson at 23:05 PM on 27 July 2010Waste heat vs greenhouse warming
TOP, you seem to be assuming that 'climate sensor density' increases the impact of a particular region on global temperature reconstructions. That would only be the case if all the results were added up and divided by the total. In actuality results are computed based on geographic distribution... thus 100 temperature stations in New York City have the same impact on the total global temperature reconstruction as ONE temperature station in a Kansas cornfield the size of New York City. _Flin_, the temperature forcing from 'waste heat' will not equal CURRENT GHG forcing until the human race uses roughly 100 times as much energy as it does now. From 1950 to 2000 energy use quadrupled... and the growth rate has since slowed. Thus, it will be at least several centuries before waste heat begins to be a problem similar to current AGW effects. In that timeframe we will likely convert to solar and wind power (indeed we must unless we go nuclear) and then just be 'moving around' energy already in the system... and the 'waste heat' issue disappears. Ergo, it is unlikely to ever be a real concern. -
Ken Lambert at 22:56 PM on 27 July 2010Assessing global surface temperature reconstructions
Ned #38 It was a bit unkind Ned - don't take it to heart. Put it down to hardened arteries and red wine. You obviously put a lot of work into the piece. My criticism centres around the notion that three analyses of the same core data somehow adds validity to the basic core data. The question to be asked is who (and where) assembled the basic core data - and how good is it?? As for moderator Johns comment; and Peter Hogarth #40 ; why does a linear trend line run from end to end of a temperature set, the best or most informative fit? It is most probable that a temperature trend is non-linear in any case. The drivers of temperature are non-linear. CO2GHG forcing is logarithmic, Solar 11 year cycle is sinusoidal, longer term Solar cycles are probably sinusoidal, Radiative cooling is exponential (with T^4), cloud and aerosol cooling nobody really knows - so what is sacred about a linear trend line?? If you do a least squares or other spline or smoothed fit - you will get flattening since about 1998 on all these temperature reconstructions. What has to be explained is how can the earth system be subjected to more forcing and produce flatter temperatures over this last 12 years or so. -
Ned at 22:46 PM on 27 July 2010The nature of authority
You can see the trend, can't you? Precipitation is highly variable, so it might be helpful to look at the entire 0-20 N region, rather than individual points. From New et al. (2001):
The x-axis runs from 1900 to 2000. Note the long-term decline starting in the 1960s.
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Rob Painting at 22:39 PM on 27 July 2010Waste heat vs greenhouse warming
RSVP - "I think I did explained above that the "rate" of transfer for the same temperature is higher via radiation then convection... please check these formulas.." No need to check formulas, you're going wrong somewhere else. How does longwave radiation leave the atmosphere?, radiation? or some other mechanism?. -
TOP at 22:33 PM on 27 July 2010Waste heat vs greenhouse warming
There is one other thing that bears looking into regarding this paper. NCDC Map shows that climate sensors have a higher concentration in the same areas that AWH is the highest. While this post gives a number of .028, the number is much higher in areas where climate sensor density is higher. "but over the continental United States and western Europe, it is +0.39 and +0.68 W/m^2" (Flanner). Flanner gives 0.39 W/m^2 for the continental US, but he doesn't give a number for the US east of the Mississippi which is probably in line with Europe's number. This can skew climate data regardless of whether the climate sensor is placed properly. Second, the local effect of AHW is very much higher on the US East Coast and this has to contribute to warming of the Gulf Stream. Third, AWH, being based on consumption primarily of coal, petroleum and nuclear continues through the night which may skew night time temperatures as measured in areas where there are high concentrations of sensors and sources (the East Coast). Fourth, AWH is also correlated with another greenhouse gas release, H20. This is also true with nuclear power where cooling towers are used. -
_Flin_ at 22:32 PM on 27 July 2010Waste heat vs greenhouse warming
Just wanted to mention that while "waste heat" is rather low compared to CO2, it is rising as well. Furthermore it is radiated back at Earth just the same through GHG (Warmth = Warmth = IR). Just because it is tiny compared to GHG, it doesn't mean it isnt important. 1% compared to greenhouse warming isn't much now, but if we are able to limit emissions of GHG, at one point the need for limiting waste heat will arise. In a few hundred years, that is. -
Ned at 22:30 PM on 27 July 2010Waste heat vs greenhouse warming
Peter, that is a useful explanation, but as I mentioned we seem to have left the topic of waste heat -- everyone seems to be OK with the figures provided by Flanner 2009 -- and we're back on the topic of the fundamental principles of the greenhouse effect and the spectral properties of gases. -
Berényi Péter at 22:23 PM on 27 July 2010The nature of authority
#141 chris at 09:38 AM on 27 July, 2010 Careful Peter. One location does not define an entire longitudinal band I know. AGW always happens elsewhere, preferably at locations with the poorest data coverage :) Anyway, according to Zhang at al. precipitation is only supposed to decrease north of the equator, while Rio Negro is located right on it.
So let's check another location. Hilo, Hawaii (General Lyman field, 19.70 N, 155.10 W) is the only station in GHCN v2 between the equator and 20 N with a reasonably long uninterrupted precipitation record (1943-2009).
You can see the trend, can't you?
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Ned at 22:18 PM on 27 July 2010It's waste heat
I agree 1000% with Doug Bostrom's comment up here, both in terms of the substantive issue and the reflections on the context that Doug offers in the first and last paragraphs. There is nothing wrong with having people come here and ask basic, even naive, questions. Like Doug, however, I am uncertain about how we as a community should respond to someone who continues to make the same fundamentally wrong claims over and over again, running over all explanations and corrections like an implacable bulldozer of willful ignorance. We have seen this before with other commenters (e.g., a certain commenter in this thread). Most of the people who comment on this site do so in good faith, with the expectation that their efforts to promote understanding won't be wasted. The presence of a commenter who is more or less impervious to reasonable discussion and the mutual sharing of ideas throws a large spanner into the works. -
Peter Hogarth at 22:12 PM on 27 July 2010Waste heat vs greenhouse warming
17.RSVP at 20:27 PM on 27 July, 2010 Imagine the atmosphere is only O2 and N2. Energy in the form of Short wave (light) radiation from the sun is incident on the earths surface where some is absorbed. Energy is transferred, the surface “warms”. Some of this energy is re-emitted from the surface as longer wavelength IR (infra red) radiation. As N2 and O2 are tightly bonded and not resonant at IR the longer wavelengths do not interact with these molecules, and IR would pass to space unimpeded. Conduction at surface, diffusion, convection would operate to ultimately increase the kinetic energy of the bulk N2 and O2, the molecules move faster, they “warm”, but radiative transfer as such is “black body” whether from Earths surface or from individual N2 and O2 molecules in Atmosphere. An equilibrium is reached, Earths surface and atmosphere warms to a given temperature. Introduce some CO2 into the atmosphere. CO2 molecules have bending bond resonances which are excited by IR wavelengths. IR is strongly absorbed. Less is radiated directly to space. Where does this energy go? The CO2 molecules increase their kinetic energy and internal energy. They “warm”. This internal energy is released (no net gain) when the molecules re-radiate (or cool) at peaks in IR according to same bond resonances. Now, some of this IR re-radiates downwards to contribute to surface warming (now we have net heat gain at surface). This extra kinetic energy is also transferred by direct collision, diffusion, as well as conduction from warmer surface and more convection so that bulk atmosphere warms more than in the non CO2 case (net gain in atmosphere). In the greenhouse case there is an extra contribution from the re-radiated energy from wavelength specific absorbed IR by CO2 (and other greenhouse gases). This is the energy that would have escaped to space in the non greenhouse scenario. A new equilibrium is reached as Earths surface and atmosphere “warms” to a higher temperature. Maybe? -
Ned at 22:02 PM on 27 July 2010Models are unreliable
Pete Ridley writes: In his counter-point, Cook talks about the urban heat island effects that are "negligible". Well, they're surely not negligible because the estimated urban warming in typical large cities exceeds the whole assumed warming caused by CO2 - something like 0.6 °C. So it matters a lot whether the urban effects are isolated. But the urban effects are far from being the only problem with the surface temperature record. The number of recently found dramatic problems with the surface record is so huge that I can't even enumerate them here”. Comparing the elevated temperature in urban areas to the magnitude of the global increase in temperatures is misleading since urban areas constitute a tiny fraction of the surface area of the earth. The greatest warming is occurring at high latitudes where there are no large urban areas. We have a thread here that addresses many of the alleged problems with the surface temperature record. In my experience, most of the "skeptical" claims about that record have turned out to be groundless once people started looking into them quantitatively. -
Ned at 21:57 PM on 27 July 2010Models are unreliable
Pete Ridley writes: And since 1998, it's just cooling. I am not aware of any global temperature index that shows a cooling trend since 1998. From Jan 1998 through last month, both satellite series (UAH and RSS) and all three of the major surface series (GISTEMP, HADCRUT, and NCDC) have a positive slope. This is pretty remarkable considering that you've cherry-picked an interval with the largest El Nino on record at the start, and a substantial La Nina near the end. FYI, here's a graph of RSS (satellite) temperatures that I posted in another thread recently:
You will note that most of the past decade has been above the 1979-2000 trend line. The apparent "flattening" you refer to is just an artifact of the more-rapid jump of temperatures at the start of this past decade (2000-2002).
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Ned at 21:43 PM on 27 July 2010Waste heat vs greenhouse warming
AWoL writes: And all the IR emitted from the earth is being absorbed by CO2, hence adding more will have very little extra effect on atmospheric temperatures. But what happens at night in say a cold region? Won't 1/2 the IR rad from CO2 be radiated back to earth if the temperature of the earth is lower than that of the atmosphere? So there would be some heat energy returned by CO2 to the surface. There are not two stockpiles of heat in the atmosphere, one that comes from CO2 and one that comes from everything else. This is the fundamental misconception that RSVP is laboring under. -
Alden Griffith at 21:41 PM on 27 July 2010Waste heat vs greenhouse warming
On a related note, I recently compared the total heat content increase in the oceans between 1994-2007 (Lyman et al 2010) and total global energy consumption during the same period (World Bank): 1994-2007 Global Energy Use: 0.578 (10^22 joules) 1994-2007 Ocean Heat Content Gain: 13.5 (10^22 joules) In short, the increase in ocean heat content during that period is 23 times greater than all of the energy used by humans during the same period. If we wanted to heat the ocean, we are doing a far better job heating it with greenhouse gases than we possibly could with direct heating. -
Ned at 21:40 PM on 27 July 2010Waste heat vs greenhouse warming
RSVP writes: Whether you realize it or not, the more you defend CO2's efficiency in transferring energy, the less significance you are actually attributing to the effects of CO2 concentration level. Why? What's the connection? You're just making stuff up. Longwave infrared radiation is absorbed by CO2 molecules (and other greenhouse gas molecules). That process is dependent on the concentration of CO2 molecules in the atmosphere; the presence of other "transparent" gases is mostly irrelevant (I write mostly because there are minor technical exceptions that are not relevant to this discussion). Individual CO2 molecules exchange energy with the rest of the atmosphere via collisions with other molecules. For a given molecule, the rate of these collisions is dependent on the overall density of the atmosphere, not the concentration of CO2 in the atmosphere -- of the billion or so collisions per second that a CO2 molecule experiences near sea level, most of them will be with N2, O2, H2O, etc. rather than with another CO2 molecule. With all due respect to my good e-friend Doug, the "rock" analogy is not really all that helpful here. Waste heat from anthropogenic sources is mostly put directly into the atmosphere, as RSVP notes. Likewise, the warming from GHGs all occurs within the atmosphere. As I said in the other thread, every CO2 molecule is effectively a tiny machine using longwave IR as fuel and putting out waste heat into the atmosphere. It's just that the flux from these molecular machines is 100X greater than the flux from our crude mechanical devices down here on the surface. -
Pete Ridley at 21:34 PM on 27 July 2010Models are unreliable
Peter Hogarth, ref. #204, I think that Physicist Luboš Motl’s blog thread “John Cook: Skeptical Science” (Note 1) Item 4 should help you. Motl says “It's cooling: Again, Cook's graphs and statements are obsolete and a few years from the moment he wrote the page were enough to falsify his new predictions about the accumulating heat. The reality is that between 1998 or 2001 or other years on one side and 2009 on the other side, the global mean temperature dropped. Sometimes it's cooling, sometimes it's warming. The year 2010 is likely to be much warmer than 2009, approaching the temperatures of 1998, but when the El Nino fully switches to a La Nina, things can be very different. The fact that there's been no significant warming for 15 years has been accepted by both sides of this debate. And since 1998, it's just cooling. Cook has no counter-arguments. He just says that the heat flows influence the temperature and I agree with that. Except that he doesn't show in which way the flows are going to go e.g. in the next 10 years”. Motl also comments at Item 5 about this thread with “Models are unreliable: Cook says that models have made predictions that were successfully compared to observations. Except that this is not enough for the models to be reliable. For them to be reliable, it would have to be the case that the models have produced no predictions that were inconsistent with the observations - because one wrong prediction is enough to falsify a model. Clearly, such falsification has taken place with all of them. In particular, all IPCC-endorsed models predicted a warming since 1998 that didn't occur. They're gone. Again, both sides agree that we can't rely on them. Kevin Trenberth agrees that the disagreement of the models and the data is a travesty. There are hundreds of recent examples showing how deeply flawed the existing IPCC-endorsed models are”. KR, Here are Motl’s comments about those global temperature measurements you were on about in #203 “Temp record is unrealiable: In his counter-point, Cook talks about the urban heat island effects that are "negligible". Well, they're surely not negligible because the estimated urban warming in typical large cities exceeds the whole assumed warming caused by CO2 - something like 0.6 °C. So it matters a lot whether the urban effects are isolated. But the urban effects are far from being the only problem with the surface temperature record. The number of recently found dramatic problems with the surface record is so huge that I can't even enumerate them here”. The rest of Motl’s thread is worth reading too – enjoy. NOTE 1) see http://motls.blogspot.com/2010/03/john-cook-skeptical-science.html Best regards, Pete Ridley -
CBDunkerson at 21:33 PM on 27 July 2010It's waste heat
RSVP #30, no you really didn't answer my questions - but hey, why not; 1: No. 2: Same as all other heat... it radiates at equal intensity in all directions. 3: "energy dissipation" is two words... and two words neither you nor I have used. Ergo, it is impossible for me to determine what meaning they are meant to have "in this context" because there is no context. 4: Same as all other matter in the universe... they absorb some wavelengths of EM radiation and allow others to pass through. Absorbed radiation is (per issue 1 above) then re-emitted, though possibly at a different wavelength. 5: The wavelengths involved are different. Specifically, Nitrogen and Oxygen are largely 'transparent' to the infrared wavelengths emitted by the planet's surface while GHGs are not. BTW, your hypothesis seems to depend on a belief that waste heat 'goes into' N2 and O2 and stays there (which is completely wrong) while solar heat somehow avoids those two elements. Which is, of course, pure nonsense. -
Paul D at 21:28 PM on 27 July 2010Waste heat vs greenhouse warming
RSVP said: "A warm rock radiates whatever heat it has accumulated from the Sun during the day and delivers it back to the heavens where it came from. " The Ville: With a delay caused by GHGs. Hence as John Cook has pointed out, we have warmer evenings. RSVP said: "In any event, whatever heat "doesnt make it back to where it came from" is responsible for leaving global temperatures at it natural level." The Ville: Levels that can be altered. Your use of 'natural level' implies to many that there is some fixed level, there isn't. RSVP said: "Also, it is interesting to note that the hotter the rock gets, the more it wants to radiate. This is very different from the warmed up air from the engine which is lingering and is in no "hurry" to cool. " TheVille: You are talking about materials science and engineering. If the 'rock' were a lump of metal it would behave in the same way as a car. ship or any other metal object. It will radiate heat and transfer heat by conduction or convection. I don't think anyone here was interested in going into such ridiculus detail. -
Ned at 21:26 PM on 27 July 2010The nature of authority
Ah. AWoL, that clarifies things a lot. In your previous comment you wrote The constant is a theoretical concept and simply,in it's present form does not match the real world which (while perhaps not intended that way) would be "fighting words" to anyone with a background in the physics of radiation. If I understand you rightly, though, you're actually asking about the relationship between emissivity and radiant exitance. For a blackbody, the thermal radiant flux emitted per unit area (M, in watts per square meter) is given by M = sigma * T^4 meaning that it's purely a function of the temperature of the blackbody (in Kelvins) and the Stefan-Boltzmann constant (5.6697 * 10^(-8) W m-2 K-4). In the real world, nothing is a blackbody, though some materials (e.g., water) are pretty darn close. Thus, we introduce the concept of a material's emissivity (the ratio of its radiant exitance to the theoretical radiant exitance of a blackbody at the same temperature): M = epsilon * sigma * T^4 If an object has uniform emissivity across a wide range of wavelengths (again, water makes a good example) we call it a gray body. Some material types have emissivities that are dependent on wavelength (quartz, for example), which makes them a bit more complicated to deal with. Emissivity isn't really a "fudge factor" any more than the "color" of an object is a "fudge factor". In fact, color (spectral reflectance) is a very good analogy for spectral emissivity. There is nothing particularly problematic about using the Stefan-Boltzmann law at typical earth surface temperatures. You can measure emissivity of objects very easily (actually, you can probably find tables with typical emissivity values on the web). So I'm really not sure what exactly prompted your comment up here. To anyone who is used to doing calculations of electromagnetic radiation fluxes it just seems wildly over-the-top. Actually, that comment reads a bit like someone claiming that the field of ballistics is garbage because it's based on Newton's inverse square law, which is purely theoretical and has to be modified empirically to account for air resistance. You write that you "attempted to get information on the application of the constant and the law, at low temperatures, but find that I have to pay for the information, which as a taxpayer rankles somewhat." That also seems kind of strange, since the application of the S-B law at normal earth temperatures is not at all obscure; it's covered in lots of textbooks. If there's some particular very specialized paper that you are looking for, would you mind telling us what it is? (I'm just curious, as it would help understand where you're coming from). I would gently suggest that one of the responsibilities of being a skeptic is appropriately modulating one's skepticism. The three comments here, here, and here might be cases where more discretion would have been in order. -
AWoL at 21:23 PM on 27 July 2010Waste heat vs greenhouse warming
RSVPsaid "Whether you realize it or not, the more you defend CO2's efficiency in transferring energy, the less significance you are actually attributing to the effects of CO2 concentration level" As a layman, having listened to both sides, that is my thinking at the moment. And all the IR emitted from the earth is being absorbed by CO2, hence adding more will have very little extra effect on atmospheric temperatures. But what happens at night in say a cold region? Won't 1/2 the IR rad from CO2 be radiated back to earth if the temperature of the earth is lower than that of the atmosphere? So there would be some heat energy returned by CO2 to the surface. -
kdkd at 21:12 PM on 27 July 2010It's waste heat
RSVP #58 "On the one hand, the more you defend CO2's efficiency in transferring energy, the less significance you are actually attributing to the effects of CO2 concentration level. " Ummm. No. These are two separate processes that are physically independent. Your logic is wrong, and your physics is deficient. -
thingadonta at 21:02 PM on 27 July 2010Waste heat vs greenhouse warming
I suspect if there is such a thing as waste heat, there is also waste cold somewhere. -
RSVP at 20:40 PM on 27 July 2010Waste heat vs greenhouse warming
Ned "There is no difference in "quality" between the 2.9 W/m2 from radiative forcing and the 0.028 W/m2 from anthropogenic waste heat. A watt is a watt! " I think I did explained above that the "rate" of transfer for the same temperature is higher via radiation then convection... please check these formulas.. http://biocab.org/Heat_Transfer.html Convective heat transfer (i.e. air needing to cool) is a function of a difference in temperature, whereas radiative cooling goes as T exp(4). -
RSVP at 20:27 PM on 27 July 2010Waste heat vs greenhouse warming
Ned I am glad you noticed that. However it doesnt mean I am denying greenhouse effects... at least those that may have elevated temperature from subzero conditions millions of years ago. Even though it is getting off topic, I did also notice to something you wrote on the Waste Heat thread which is related to what you have brought up here. << Ned "Likewise, most of the heat from GHG absorption will also be transferred to O2 and N2 molecules, thanks to the fact that each CO2 molecule collides with N2 or O2 molecules roughly one billion times per second." >> Whether you realize it or not, the more you defend CO2's efficiency in transferring energy, the less significance you are actually attributing to the effects of CO2 concentration level. -
RSVP at 20:20 PM on 27 July 2010It's waste heat
doug_bostrom I went there and (as before) read... "Likewise, most of the heat from GHG absorption will also be transferred to O2 and N2 molecules, thanks to the fact that each CO2 molecule collides with N2 or O2 molecules roughly one billion times per second." On the one hand, the more you defend CO2's efficiency in transferring energy, the less significance you are actually attributing to the effects of CO2 concentration level. -
AWoL at 20:10 PM on 27 July 2010The nature of authority
To Berenyi Peter,post 129. Many thanks for your clear explanation. And to Ned. I am not trolling or seeking to foist radical wacky new ideas on the world of physics. I am not a climate scientist or physicist, but a veterinarian, who has over the years picked up bits of information, some good and some bad.I want to rearrange and check that information. Anyway, the (Stef-Bol)constant is applicable at lower temperatures,and is widely used in the food industry.However,in the article I read, there was a comment to the effect that the computed temperature or heat given off by staightforward application of the formula would be higher than encountered in practice.So an arbitrary factor in the form of "emissivity" was applied. As this,as far as I am aware,is derived empirically, would I be right in deducing that this factor is a combination of actual emissivity(yet to be explained)and a convenient"fudge factor"? If there is a fudge factor,doesn't that point to something "not quite right"? I have attempted to get information on the application of the constant and the law, at low temperatures, but find that I have to pay for the information, which as a taxpayer rankles somewhat. Once again,thanks to Berenyi Peter for his positive response to my post, which perhaps should have taken the form of a question, rather than an assertion. -
Ned at 20:07 PM on 27 July 2010Waste heat vs greenhouse warming
RSVP writes Seen this way, I would even venture to suggest that the real comparison should be between 0.028 and zero. I didn't really notice this earlier, but there seems to be no dispute over the actual accounting of waste heat. Instead, RSVP's actual claim seems to be that the greenhouse effect does not exist (heating from CO2 should be "zero"). If that is in fact the real position motivating RSVP's involvement here, this discussion is almost certainly going to go nowhere. -
Ned at 20:00 PM on 27 July 2010Waste heat vs greenhouse warming
Thanks for this thread, John. RSVP writes: In terms of accounting, this is very different from the 2.9 W/m2 that is being "slowed" down by GHGs but eventually makes its way up and out. Seen this way, I would even venture to suggest that the real comparison should be between 0.028 and zero. If not, what part of the 2.9 W/m2 is not making its way out? There is no difference in "quality" between the 2.9 W/m2 from radiative forcing and the 0.028 W/m2 from anthropogenic waste heat. A watt is a watt! There is no magic Heat Fairy who sits in the atmosphere and says "This packet of energy came originally from absorption of IR by a CO2 molecule, so I'll make it go away; that packet came from someone's car engine, so I'll keep it around and let it accumulate." Effectively all of the heat from IR absorbed by GHGs is shared with the rest of the atmosphere including the O2 and N2 that RSVP thinks are somehow noteworthy here. It's not kept in solitary confinement in CO2 molecules, isolated from the rest of the system until it radiates outward into space. -
RSVP at 19:48 PM on 27 July 2010Waste heat vs greenhouse warming
doug_bostrom at 17:50 PM on 27 July, 2010 Any difference between a warm rock and a warm engine, thermally speaking, RSVP? A warm rock is not shrouded with a cooling circuit pumping excess heat to a heat exchanger and elevating the temperature of air (N2, O2). A warm rock radiates whatever heat it has accumulated from the Sun during the day and delivers it back to the heavens where it came from. Some of this heat, in fact, does heat up the surrounding air by convection as does the engine, but about 150 years ago this didnt seem so interesting to scientists in explaining the effect of GHGs. In any event, whatever heat "doesnt make it back to where it came from" is responsible for leaving global temperatures at it natural level. Also, it is interesting to note that the hotter the rock gets, the more it wants to radiate. This is very different from the warmed up air from the engine which is lingering and is in no "hurry" to cool. It will only give up this energy in fact when it runs into something cooler. Something on the surface of the Earth. Not a hot rock of course. Something cooler, like ice. -
Paul D at 19:11 PM on 27 July 2010Waste heat vs greenhouse warming
I agree John. Despite the greater efficiencies, we use more energy and hence produce more waste heat today than we did in the past. Breaking heat sources down: 1. Heat generated from fuel use, this includes heat emitted at power stations/generators and from the use of products that use the energy produced from fuels, the manufacture of products etc. 2. Heat emitted by the earth. eg. all forms of geothermal. 3. Heat from solar sources. This indirectly includes renewable energy, although for the for-see-able future renewables will also have other energy inputs as well. 4. Stored energy in atoms (nuclear energy). I suppose in some respects this can be lumped in with geothermal, although nuclear energy is human activated. -
John Russell at 18:14 PM on 27 July 2010Waste heat vs greenhouse warming
Marcus @#1 Are you sure what you say is correct? The term 'waste heat' is, I think, rather confusing. As I understand it, the heat generated by human beings -- which is the 'waste heat' we're talking about -- has nothing to do with how thermally-efficient our houses, factories and other activities are. Clearly the vast majority -- if not all -- of the energy used by humans will end up eventually as heat, even if it's doing useful work. So the total amount of 'waste heat' must be, by definition, the sum of the energy contained in all the fuels we're burning. As the total amount of fuel burnt by humans has increased steadily since the 19th century, so the amount of heat being produced and absorbed by the environment has increased. But as most of the fuel we consume also produces CO2 then the waste heat build-up adds to the heat retained by the greenhouse effect at a similar rate (though in a different proportion). However, as others have said, 'waste heat' -- which I'd suggest is better called 'by-product heat' -- represents only a tiny percentage of the overall anthropogenic warming. This is a lay explanation of the science as I understand it from reading what others have said, so maybe one of the scientists can confirm that my understanding is correct. -
Paul D at 18:09 PM on 27 July 2010Waste heat vs greenhouse warming
Long term and massive use of nuclear and geo-thermal energy would warm us, according to Eric Chaisson: http://www.tufts.edu/as/wright_center/eric/reprints/eos__agu_transactions_chaisson_8_july_08.pdf
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