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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 105951 to 106000:

  1. CO2 lags temperature
    Sentient, can you provide a link or citation for Tzedakis' paper? Can't find it, would like to take a look. BTW, mistermack might want to read sentient's post so as to get a better understanding of how tracking insolation for a single day is actually employed. Reevaluate what's "worthless," your remark versus the science.
  2. Waste heat vs greenhouse warming
    KR #301 Thanks for the answer.
  3. Waste heat vs greenhouse warming
    pbjamm #302 "It really appears to me that you are being argumentative rather than arguing." Well it's a shame it appears that way, but I am being asked to justify things that to me are fairly obvious. For instance, there are those that would just as well hang out downwind from a forest fire than upwind, or assume the plume of ash and gases from Iceland that stretched all the way to the Baltic, (now maybe it was just only Scotland, very sorry), contained no latent heat whatsoever, etc. What is more of a shame is the distraction from the real discussion, especially what appears to be pure provocation, that is best ignored, although it can be difficult.
  4. The 2nd law of thermodynamics and the greenhouse effect
    At least once I agree with SkS. This is some point where some skeptics are horribly wrong. Not including me.
  5. CO2 lags temperature
    You know, in science, there was once this thing we called the Theory of Multiple Working Hypotheses. Anathema (a formal ecclesiastical curse accompanied by excommunication) in modern climate science. So, in juxtaposition to the hypothesis of future global climate disruption from CO2, a scientist might well consider an antithesis or two in order to maintain ones objectivity. One such antithesis, which happens to be a long running debate in climate science, concerns the end Holocene. Or just how long the present interglacial will last. Looking at orbital mechanics and model results, Loutre and Berger (2003) in a landmark paper (meaning a widely quoted and discussed paper) for the time predicted that the current interglacial, the Holocene, might very well last another 50,000 years, particularly if CO2 were factored in. This would make the Holocene the longest lived interglacial since the onset of the Northern Hemisphere Glaciations some 2.8 million years ago. Five of the last 6 interglacials have each lasted about half of a precession cycle. The precession cycle varies from 19-23k years, and we are at the 23kyr part now, making 11,500 years half, which is also the present age of the Holocene. Which is why this discussion has relevance. But what about that 6th interglacial, the one that wasn’t on the half-precessional “clock”. That would be MIS-11 (or the Holsteinian) which according to the most recently published estimate may have lasted on the order of 20-22kyrs, with the longest estimate ranging up to 32kyrs. Loutre and Berger’s 2003 paper was soon followed by another landmark paper by Lisieki and Raymo (Oceanography, 2004), an exhaustive look at 57 globally distributed deep Ocean Drilling Project (and other) cores, which stated: “Recent research has focused on MIS 11 as a possible analog for the present interglacial [e.g., Loutre and Berger, 2003; EPICA community members, 2004] because both occur during times of low eccentricity. The LR04 age model establishes that MIS 11 spans two precession cycles, with 18O values below 3.6o/oo for 20 kyr, from 398-418 ka. In comparison, stages 9 and 5 remained below 3.6o/oo for 13 and 12 kyr, respectively, and the Holocene interglacial has lasted 11 kyr so far. In the LR04 age model, the average LSR of 29 sites is the same from 398-418 ka as from 250-650 ka; consequently, stage 11 is unlikely to be artificially stretched. However, the June 21 insolation minimum at 65N during MIS 11 is only 489 W/m2, much less pronounced than the present minimum of 474 W/m2. In addition, current insolation values are not predicted to return to the high values of late MIS 11 for another 65 kyr. We propose that this effectively precludes a ‘double precession-cycle’ interglacial [e.g., Raymo, 1997] in the Holocene without human influence.” To bring this discussion up to date, Tzedakis, in perhaps the most open peer review process currently being practised in the world today (The European Geosciences Union website Climate of the Past Discussions) published a quite thorough examination of the state of the science related to the two most recent interglacials, which like the present one, the Holocene (or MIS-1) is compared to MIS-19 and MIS-11. The other two interglacials which have occurred since the Mid Pleistocene Transition (MPT) also occurred at eccentricity minimums. Since its initial publication in 2009, and its republication after the open online peer review process again in march of this year, this paper is now also considered a landmark review of the state of paleoclimate science. In it he also considers Ruddiman’s Early Anthropogenic Hypothesis, with Rudddiman a part of the online review. Tzedakis’ concluding remarks are enlightening: “On balance, what emerges is that projections on the natural duration of the current interglacial depend on the choice of analogue, while corroboration or refutation of the “early anthropogenic hypothesis” on the basis of comparisons with earlier interglacials remains irritatingly inconclusive.” As we move further towards the construction of the antithetic argument, we will take a closer look at the post-MPT end interglacials and the last glacial for some clues. An astute reader might have gleaned that even on things which have happened, the science is not that particularly well settled. Which makes consideration of the science being settled on things which have not yet happened dubious at best. Higher resolution proxy studies from many parts of the planet suggest that the end interglacials may be quite the wild climate ride from the perspective of global climate disruption. Boettger, et al (Quaternary International 207 [2009] 137–144) abstract it: “In terrestrial records from Central and Eastern Europe the end of the Last Interglacial seems to be characterized by evident climatic and environmental instabilities recorded by geochemical and vegetation indicators. The transition (MIS 5e/5d) from the Last Interglacial (Eemian, Mikulino) to the Early Last Glacial (Early Weichselian, Early Valdai) is marked by at least two warming events as observed in geochemical data on the lake sediment profiles of Central (Gro¨bern, Neumark–Nord, Klinge) and of Eastern Europe (Ples). Results of palynological studies of all these sequences indicate simultaneously a strong increase of environmental oscillations during the very end of the Last Interglacial and the beginning of the Last Glaciation. This paper discusses possible correlations of these events between regions in Central and Eastern Europe. The pronounced climate and environment instability during the interglacial/glacial transition could be consistent with the assumption that it is about a natural phenomenon, characteristic for transitional stages. Taking into consideration that currently observed ‘‘human-induced’’ global warming coincides with the natural trend to cooling, the study of such transitional stages is important for understanding the underlying processes of the climate changes.” Hearty and Neumann (Quaternary Science Reviews 20 [2001] 1881–1895) abstracting their work in the Bahamas state: “The geology ofthe Last Interglaciation (sensu stricto, marine isotope substage (MIS) 5e) in the Bahamas records the nature of sea level and climate change. After a period of quasi-stability for most of the interglaciation, during which reefs grew to +2.5 m, sea level rose rapidly at the end ofthe period, incising notches in older limestone. After briefstillstands at +6 and perhaps +8.5 m, sea level fell with apparent speed to the MIS 5d lowstand and much cooler climatic conditions. It was during this regression from the MIS 5e highstand that the North Atlantic suffered an oceanographic ‘‘reorganization’’ about 11873 ka ago. During this same interval, massive dune-building greatly enlarged the Bahama Islands. Giant waves reshaped exposed lowlands into chevron-shaped beach ridges, ran up on older coastal ridges, and also broke off and threw megaboulders onto and over 20 m-high cliffs. The oolitic rocks recording these features yield concordant whole-rock amino acid ratios across the archipelago. Whether or not the Last Interglaciation serves as an appropriate analog for our ‘‘greenhouse’’ world, it nonetheless reveals the intricate details ofclimatic transitions between warm interglaciations and near glacial conditions.” The picture which emerges is that the post-MPT end interglacials appear to be populated with dramatic, abrupt global climate disruptions which appear to have occurred on decadal to centennial time scales. Given that the Holocene, one of at least 3 post-MPT “extreme” interglacials, may not be immune to this repetitive phenomena, and as it is half a precession cycle old now, and perhaps unlikely to grow that much older, this could very well be the natural climate “noise” from which we must discern our anthropogenic “signal” from. If we take a stroll between this interglacial and the last one back, the Eemian, we find in the Greenland ice cores that there were 24 Dansgaard-Oeschger oscillations, or abrupt warmings that occurred from just a few years to mere decades that average between 8-10C rises (D-O 19 scored 16C). The nominal difference between earth’s cold (glacial) and warm (interglacial) states being on the order of 20C. D-O events average 1470 years, the range being 1-4kyrs. Sole, Turiel and Llebot writing in Physics Letters A (366 [2007] 184–189) identified three classes of D-O oscillations in the Greenland GISP2 ice cores A (brief), B (medium) and C (long), reflecting the speed at which the warming relaxes back to the cold glacial state: “In this work ice-core CO2 time evolution in the period going from 20 to 60 kyr BP [15] has been qualitatively compared to our temperature cycles, according to the class they belong to. It can be observed in Fig. 6 that class A cycles are completely unrelated to changes in CO2 concentration. We have observed some correlation between B and C cycles and CO2 concentration, but of the opposite sign to the one expected: maxima in atmospheric CO2 concentration tend to correspond to the middle part or the end the cooling period. The role of CO2 in the oscillation phenomena seems to be more related to extend the duration of the cooling phase than to trigger warming. This could explain why cycles not coincident in time with maxima of CO2 (A cycles) rapidly decay back to the cold state. ” “Nor CO2 concentration either the astronomical cycle change the way in which the warming phase takes place. The coincidence in this phase is strong among all the characterised cycles; also, we have been able to recognise the presence of a similar warming phase in the early stages of the transition from glacial to interglacial age. Our analysis of the warming phase seems to indicate a universal triggering mechanism, what has been related with the possible existence of stochastic resonance [1,13, 21]. It has also been argued that a possible cause for the repetitive sequence of D/O events could be found in the change in the thermohaline Atlantic circulation [2,8,22,25]. However, a cause for this regular arrangement of cycles, together with a justification on the abruptness of the warming phase, is still absent in the scientific literature.” In their work, at least 13 of the 24 D-O oscillations (indeed other workers suggest the same for them all), CO2 was not the agent provocateur of the warmings but served to ameliorate the relaxation back to the cold glacial state, something which might have import whenever we finally do reach the end Holocene. Instead of triggering the abrupt warmings it appears to function as somewhat of a climate “security blanket”, if you will. Therefore in constructing the antithesis, and taking into consideration the precautionary principle, we are left to ponder if reducing CO2’s concentration in the late Holocene atmosphere might actually be the wrong thing to do.
    Moderator Response: Your comment likely will spark discussion that belongs on the thread We’re heading into an ice age. So will you please copy it into a comment on that thread? Then post a new comment on this thread, simply pointing to your comment's new home. When you have done that, I'll delete this original comment from this thread. Thanks.
  6. Waste heat vs greenhouse warming
    archiesteel #303 "I want to see you post an example that clearly illustrates what you claim" As I was saying earlier RSVP #292 "...if it isnt found on the internet, it cant be true." muoncounter #304 "1320 MW" Since ALL that energy is going straight up, lets just hope the IR detector has some major filters in place.
  7. DMI and GISS Arctic Temperatures: Hide the Increase?
    Peter, you ought to think about updating your main post w/that "reanalysis." A shame to have it buried in the 3rd page of comments... Nice work. BTW, if you're looking for a decent chart/plotting package without any encumbrances, take a look at gnuplot if you've not already done so.
  8. Waste heat vs greenhouse warming
    @muoncounter: thanks for this convincing demonstration.
  9. Waste heat vs greenhouse warming
    #300: "command hot air to blow straight up" Here's a graphic illustration that all this waste heat discussion is just so much hot air: The 1320 MW power plant Joliet 29 is shown as the light blue cluster in the upper left-center in the upper image (visible and NIR); the waste heat, both from its structures and its cooling pond, are shown as white-red in the lower (ASTER) thermal image. Within the confines of the pond, the false-color IR has gone back to green, which is only slightly warmer than the heat signature of the nearby environment. Also note this plant's CO2 emissions in 2006: 6.5 Megatons. Unlike this waste heat and all the hot air it has generated here, that CO2 is still out there.
  10. David Wrathall at 03:31 AM on 24 October 2010
    Newcomers, Start Here
    Thank you archiesteel and Riccardo, your comments explain both the extreme narrowness and misleading nature of this source. On the basis of this I could and will (if necessary) respond to Wilson Flood on the BANC website. However, I think it would be far more effective if you could post a response on the site if at all possible. Wilson also says this: "Carbon dioxide absorbs heat energy only at specific wavelength bands. Once all the energy at that wavelength band is absorbed adding more gas has no effect whatsoever. There is already enough carbon dioxide in the atmosphere such that all the energy at the centre of the band is absorbed." I guess there's already evidence to refute this assertion somewhere on this site. If you're aware of it, I'd really appreciate a link to it or your take on it if possible. Many many thanks for your responses. David
    Moderator Response: CO2 effect is saturated
  11. The science isn't settled
    @mistermack: please read the "It's not bad" article. At least now you're acknowledging that AGW is real. It took some time to get you to admit it, but your last sentence leaves no room for interpretation.
  12. Waste heat vs greenhouse warming
    @RSVP: "You keep insisting I produce a map and that I claim something about maps existing" I didn't ask for a map, I asked for the map-like projection you mentioned. You know, like when you said: "So instead of the effect you describe, as seen from a map, there is typically a large smudge or plume that emerges around an urban center that tapers eastward... heat that is gradually dispersed but never lost" I want to see you post an example that clearly illustrates what you claim. And no, the middle image above doesn't count, as it does not include city limit, and it seems to be an averaged measurement. You also don't have wind patterns indicated. I'm still waiting. "Again, your insistence in all this is just a way to detract from the topic at hand" No, I'm just trying to keep you accountable, which you are trying to avoid by any means necessary. "Congradulations! You are king of the hill." Sorry, but you lost the debate days ago. You're just trying to squirm your way out of it, and it's kind of sad to watch.
  13. CO2 lags temperature
    #181: "A tiny CO2 rise, following 800 years after a miniscule rise in insolation due to the Milankovitch cycle, just doesn't fit the bill. At the depth of the ice-age, a high proportion of the sun's energy is being reflected back into space anyway." Your remarks convey a very one-sided sense of scale. A tiny CO2 rise? Look at the CO2 graph you posted in #178: 180ppm at LGM, 280 at the graph's t=0 and 390 now. Those are not tiny changes. A high proportion of solar energy reflected back to space? This requires that you understand how the LGM changed the total albedo of both the sum total land area and the oceans basins. From Broccoli and Manabe 1987: ... both the ice sheet and CO2 effects are found to be required in order to produce sufficient cooling on a global basis. ... the loss of heat energy due to the reflection of solar radiation by Northern Hemisphere continental ice is almost entirely compensated by a reduction in the upward terrestrial radiation from that hemisphere.
  14. DMI and GISS Arctic Temperatures: Hide the Increase?
    @FLansner: when accused of pixel counting, you pointed to graphs and suggest we eyeball them as confirmation of your thesis. Basically, you just proved the accusation. Instead of eyeballing, which can be misleading, why not do as Peter did and use actual data to produce charts using the appropriate software?
  15. Waste heat vs greenhouse warming
    RSVP - It really appears to me that you are being argumentative rather than arguing. I have read this entire thread and am still unclear what it is you are trying to say. @300 - "Actually if you take a look at the center image above, you will notice the contours indicating temperatures actually are asymetrical around city center, with warmer temperatures downwind." Two problems with this claim. Cities are asymmetrical and the map does not include any wind information from which to draw your conclusion.
  16. Waste heat vs greenhouse warming
    RSVP - If you want to know the theoretic energy use that (with no GHG production) would raise global temps by 1.0°C, just turn the equation around: dT / λ = dF That's why I like giving the appropriate equations - you could have done this yourself. Averaging λ to be 0.87, dF = 1.15 W/m^2. Current forcing with an energy use of 15 TW is 0.028 W/m^2. Therefore to reach 1.15 W/m^2 and 1.0°C of energy change we would need to use 41x our current energy, or 615 TW. With the range of climate sensitivity going from 0.54 to 1.2, that might range from 0.62°C to 1.38°C, but it's a mid-range estimate. Hmmm - I don't need any lakes boiled at the moment... But to return to the topic of this thread - Waste Heat is not responsible for the current warming (0.8°C and nowhere near equilibrium); it might at equilibrium add 0.015°C to 0.034°C.
  17. CO2 lags temperature
    @mistermack: you clearly didn't understand what CBDunkerson explained. During those times, CO2 was a feedback. When the main forcing stopped, the feedback diminished. Today the situation is different. We don't have an insolation-based forcing. However, CO2 levels are 35% higher than at the highest point during the past 600,000 years. It *is* the forcing, not the feedback. If you disagree, please provide scientific evidence supporting your point of view. Anything else will be ignored as more noise from the contrarian side.
  18. The 2nd law of thermodynamics and the greenhouse effect
    Bibliovermis, the blanket analogy is precisely that, an analogy. It is not a model that represents every aspect of global warming. Nor does it need to, it shows the point that a warm body can be made warmer by something cooler, without violating the second law. So it's enough to disprove the skeptics' claim. Tarcisio, are you implying that the second law does not apply to radiation? If that were true then this rebuttal would not need to exist. As it is, the second law applies equally to all forms of heat-transfer - you will not find a textbook anywhere that defines the second law as behaving differently for conduction, convection, or radiation. KirkSkywalker, nothing in this rebuttal is specific to a certain gas, any GHG will exhibit the same effect. CO2 is important because there's so much of it, and adding more is like adding another blanket, and another, and another. As others have pointed out (#3, #14) I didn't emphasise this point enough in the post, but adding more blankets will make you warmer, even though the outermost blanket may itself be quite cold.
  19. CO2 lags temperature
    CB, you clearly don't rate CO2 as having much of a greenhouse effect, if you think that a slight drop in insolation could halt temperature rises, at a point of extremely high and rising CO2 levels. A factor of 1 could hardly suddenly drag the world out of the depths of an ice-age, all the way to the hottest point in the cycle.
  20. Tarcisio José D at 02:01 AM on 24 October 2010
    The 2nd law of thermodynamics and the greenhouse effect
    Visitei o site sugerido por LukeW, scienceofdoom.com e achei um absurdo aplicar a segunda lei aos corpos sujeitos à energia radiante. É como se um corpo ao receber energia radiante mandasse a energia parar e responder se veio de um corpo mais quente ou mais frio. Se a resposta for mais quente, pode entrar, caso contrario será bloqueada. Quanto a questão da atmosfera ser mais fria que o solo, podemos diser a mesma coisa. O solo recebe milhões de emissões das particulas do ar e não tem a propriedade de escolher se esta emissões provem de um corpo mais quente ou mais frio. Ele simplesmente recebe esta energia. "Google tranlated" I visited the site suggested by LukeW, scienceofdoom.com and thought absurd to apply the second law for bodies subjected to radiant energy. It's like a body to receive radiant energy to send power to stop and answer came from a body warmer or colder. If the answer is hotter, you can get, otherwise it will be blocked. Regarding the question of the atmosphere is colder than the ground, we see the same thing. The soil receives millions of emission of particles from the air and has no property to choose whether this emission comes from a body warmer or colder. He just gets this energy.
  21. The science isn't settled
    Archie, the difference is, a plane crash is almost 100% bad. A bit of warming isn't. (Certainly not for Britain). So it's not black and white like a plane crash. And considering that without MMGW, if you go by the previous cycles, we are due to drift into a full ice-age, a moderate amount of warming might be a good thing for the rest of the planet too.
    Moderator Response: Further comments on warming's benefits versus costs must be made on It's Not Bad. Further comments on the need to prevent the next ice age must be on We’re Heading Into an Ice Age.
  22. It's the sun
    e #717 This is the introduction to your cited Hansen paper: "Our climate model, driven mainly by increasing humanmade greenhouse gases and aerosols among other forcings, calculates that Earth is now absorbing 0.85 ± 0.15 W/m2 more energy from the Sun than it is emitting to space. This imbalance is confirmed by precise measurements of increasing ocean heat content over the past 10 years." I don't think so. OHC content measurement debated at great length elsewhere on this blog eg; "Robust warming of the global upper oceans" has shown that OHC measurement is everything but precise. Even Dr Trenberth who would be on the same side of the debate as Hansen can only find 60% of the OHC increase posed by the 0.9W/sq.m imbalance. Will post my numbers when completed and checked. You all can be my peer review.
  23. Waste heat vs greenhouse warming
    archiesteel You keep insisting I produce a map and that I claim something about maps existing, etc. Someone's imagination definitely got sparked and related the word "map" to satellite surface imagery. Actually if you take a look at the center image above, you will notice the contours indicating temperatures actually are asymetrical around city center, with warmer temperatures downwind. I'm sure real estate agents would be thrilled have the kind of control on physics that you purport so that they could indeed command hot air to blow straight up around houses they cant sell. Again, your insistence in all this is just a way to detract from the topic at hand which looks like your best shot. Congradulations! You are king of the hill.
  24. Vote for SkS in the physics.org web awards
    Come on people, voting was not so difficult. :-) You do not vote a single website; you can give 1-5 'points' to any of the shortlisted websites for each group. You have the chance to visit the sites first before voting. Open new tabs for each website. When you do the rating for each website (selecting 1-5 stars), the system sends your vote to physics.org to get counted.
  25. CO2 lags temperature
    mistermack #181: "Archie, "never stop" was not meant to be taken literally. (why do I have to explain that?)" Because it's the opposite of what you said? "If CO2 is the main driver, the feedback loop would have to continue as long as there was dissolved CO2 available to come out of the oceans." Why? If we take humans digging up and burning fossil fuels out of the equation then rising CO2 levels are a FEEDBACK. Once the forcing, in this case increased insolation of the northern latitudes, stops the feedback will eventually stop as well. Look at the ice-albedo feedback for example. Even if we stopped increasing atmospheric CO2 levels today ice would continue to melt for decades to centuries. It should not be at all surprising that there is a lag time between the point that a forcing peaks and the point that all of the feedbacks caused by that forcing peak. "And as I said earlier, what is the sudden stopping mechanism?" So long as the feedback factor is less than 1 it is simple mathematics that once the forcing ends the feedback must eventually do so as well. Ergo, the 'stopping mechanism' is quite obviously the end of the forcing. When you move your foot from the accelerator to the brakes of your car does the vehicle stop instantly? If not, why would you think that the entire planet can shift directions on a dime?
  26. DMI and GISS Arctic Temperatures: Hide the Increase?
    Hi Peter! At first glimpse your work appears brilliant, i will dig into it as soon as i get a little time. I just want to comment fast: The general picture, that the dive in DMI data might be caused by my pixel counting is flat wrong. Just check out years in the DMI link: http://ocean.dmi.dk/arctic/meant80n.uk.php 1991, 1993-4 shows temperatures above average in the melting period while 2010 shows temperatures clearly below average. So the essence here has nothing to do with my pixel counting that could lead to a little marginal error in both directions. So therefore as i said earlier, either DMI´s data in melt season are pretty useless or else we have had a cooling in the meltperiod 80N-90N from 1991 and foreward. And both options to me are surpricing and "hard to swallow". If you are correct above, then i believe that DMI´s presentations contains rather fundamental errors. It simply doens make sence to present melting temperatures warmer than average in 1991 and colder than average in 2010 if this has nothing to do with reality. I think i will forward your work to DMI, perhaps? K.R. Frank Lansner
  27. CO2 lags temperature
    Archie, "never stop" was not meant to be taken literally. (why do I have to explain that?) If CO2 is the main driver, the feedback loop would have to continue as long as there was dissolved CO2 available to come out of the oceans. Which would heat the planet way past the point where it "did" stop. Is that any easier? If you look at the graph I posted above, where I averaged out the peaks and troughs, you can see that the trend is a continuous fall into an ice age, until some drastic event causes a spectacular temperature rise to a one-off peak, with this repeated over and over. It doesn't reflect the patterns of the Milankovitch cycles at all. Find out what drives that huge rise, and you will know what drives the climate. That's why the widely accepted 800 year lag is important. A tiny CO2 rise, following 800 years after a miniscule rise in insolation due to the Milankovitch cycle, just doesn't fit the bill. At the depth of the ice-age, a high proportion of the sun's energy is being reflected back into space anyway. I can't see a slow, tiny, gradual increase in insolation causing such a sudden and violent rise. And as I said earlier, what is the sudden stopping mechanism?
  28. DMI and GISS Arctic Temperatures: Hide the Increase?
    FLansner at 08:16 AM on 23 October, 2010 Klaus Flemløse at 02:50 AM on 23 October, 2010 Albatross at 09:51 AM on 22 October, 2010 (and thanks also the many others who have commented). I have concentrated my efforts on the two points of 1) possible pixel counting errors in the Lansner data, and 2) possible bias steps in actual DMI data. This highlights significant problems with the Lansner chart. My summary based on the best available evidence is that Summer Arctic temperatures are increasing slightly, the Lansner chart contains errors and any conclusions based on this chart are likely to be incorrect. 1) I used an evaluation version of a commercial chart conversion software package to carefully create a “pixel counted” version of the DMI daily data for the past few years. I then compared this with the real DMI data. Some of the Summer daily values were as different as -0.98 or +0.84 degrees C. Difference values in Winter are much larger, but the re-generated overall charts looked very similar visually. Because the “above zero degrees C” only covers a few days, and it is above a threshold, any errors have high impact here, especially as the data is extracted from a different DMI chart for each year, each with potential scale and offset errors. I have concluded that "pixel counting" is not an appropriate method for analysing trends or data in this case. The Lansner chart has large differences from the correct DMI values and it appears the conversion of numerical data to images and then pixel counting from these images is easily capable of creating bad data. 2) I obtained daily ERA-Interim 2m air temperature data from 1989 to 2009 gridded for 80.25N to 90N. The ERA-Interim uses identical raw data inputs to the operational models used in DMI, but is a re-analysis, where a great deal of attention has been paid to systematically resolving small bias differences (particularly between different satellite sensors), so that the re-analysis can be used for climatology purposes and trend analysis (Dee 2009, ECMWF Newsletter). The absolute temperature plots of both ERA-Interim and DMI for 2008 (or any other year in the overlap period) indicate that the underlying raw data is almost identical. I used the daily ERA-Interim >80N data to look at the Summer melt above zero degrees C in exactly the same way as we have treated the DMI data. Results are plotted for daily minimum air temperatures greater than zero degrees C and also daily maximum air temperatures to look at possible differences. The ERA-Interim trends over the period 1989 to late 2009 for both Tmax and Tmin are identical and positive. This means it is likely that bias steps are affecting the real DMI melt season data. The two operational model transitions in DMI at 2002 and 2006 are identified with crosses below, but there are other points where new satellite data streams are assimilated where bias errors have been identified and addressed comprehensively in ERA-Interim. A rolling 365 day average plot was then generated based on the daily data from DMI and ERA-Interim, which highlights the small bias steps in the DMI series which are likely to be related to the changes briefly described in the “advanced” article. The ERA-Interim >80N 2m air temperature trend from 1989 to 2009 is 1.27 degrees C/decade. Based on the most comprehensive data set we currently have, it appears GISS is underestimating the recent high Arctic temperature trends, and the Arctic is not currently “cooling” through the melt season.
  29. Waste heat vs greenhouse warming
    Oh, and where are those map-like top projections that show UHI effects "trailing off"? I mean, you must have some handy, considering you claimed they existed several posts ago, right? Right? You know, unless you made that up.
  30. Waste heat vs greenhouse warming
    @RSVP: you didn't mention that, in that hypothetical scenario, humans were still emitting GHGs. How am I supposed to know what's in your imaginary world? Maybe it's full of grazing unicorns whose flatulence actually remove methane from the air. Your cooking analogy is similarly flawed. But hey, you're clearly lonely, who am I to judge.
  31. Waste heat vs greenhouse warming
    archiesteel #293 "how about "100 times," Looks like you forgot about the effects of GHG. 100 seems too high now. I do a lot of cooking, and turn the flame down when I put the lid on the pot. It doesnt take much to keep the pot going once the right temperature is reached.
  32. Waste heat vs greenhouse warming
    Oh, and KR did provide a decent answer. You should apologize to him for your rude behavior. Moderators, you should delete this entire exchange.
  33. Waste heat vs greenhouse warming
    Replying to yourself, RSVP? (You posted #292.) The answer to your question is no. It didn't even stop when contrarians began to ignore the facts to spew strange theories and engage in amusing but otherwise wasteful sophistry.
  34. Waste heat vs greenhouse warming
    #292 One question leads to another, not that KR shouldnt provide a decent answer, but here's one more. Did scientific inquiry stop when AGW was formulated? Just a question.
  35. Waste heat vs greenhouse warming
    @RSVP: I don't really think you're looking for an answer. You're just here to waste people's time. If I'm wrong, and you *are* looking for an answer, how about "100 times," since waste heat is 100x smaller than AGHG forcings. Two orders of magnitude. You know, what it says in the article above.
  36. Waste heat vs greenhouse warming
    doug_bostrom #291 On the otherhand, for the so called "non-skeptic", if it isnt found on the internet, it cant be true... most amusing indeed.
  37. Climate cherry pickers: Falling humidity
    Thanks for the clarification Kooiti. Readers might want to view a video of Andrew Dessler addressing the humidity issue & climate sensitivity at Deltoid
  38. Vote for SkS in the physics.org web awards
    Tenney Naumer... What's a VCR? :-)
  39. Vote for SkS in the physics.org web awards
    I believe this nomination is nothing to do, directly, with the AGW/Anti-AGW debate or SkS position on it; except so far as this debate has forced a lot of people to communicate science in general and physics in particular, at a number of levels, with the general public. As a spin-off of this 'debate' sites like SkS have provided some stupendous explanations, digestible by anyone and everyone, whatever their perspective on AGW. SkS's 3 level explanations, appropriate use of graphs, equations, analogies etc. is clearly a great example of the communications of science with the general public - what ever your perspective on climate change.
  40. The 2nd law of thermodynamics and the greenhouse effect
    Glenn Tamblyn it shouldn't be necessary to add "net" to heat, it is already the net energy exchange (or flux). Though, you're right that there's a lot of confusion on this concept, we all often call heat the energy emitted by warm bodies (the Stefan-Boltzman law).
  41. Waste heat vs greenhouse warming
    Is there any amount of energy put out by man on a continual basis that could cause the Earth's temperature to rise, say 1 degree C? The amusing thing about that question is that to a "skeptic" a proper answer would be impossible for all the same sorry reasons we're familiar with. A model would be necessary, feedbacks accounted for, parameterizations established, etc.
  42. Waste heat vs greenhouse warming
    Daniel Bailey #288 You just stepped in something. Check your shoe.
  43. Waste heat vs greenhouse warming
    To archiesteel... It is accurate to say a response is not an answer. KR The answer only required a YES or a NO, and a number please if YES. Let me put training wheels on the question and rephrase. Is there any amount of energy put out by man on a continual basis that could cause the Earth's temperature to rise, say 1 degree C?
  44. The 2nd law of thermodynamics and the greenhouse effect
    Tony Several comments have already mentioned this, and I understand that this is a basic post, but the distinction between 'Heat cannot flow from a cold source to a hot source' (NOT a correct statement of the 2nd Law) and 'NET Heat cannot flow from a cold source to a hot source' (A more correct statement - we wont mention entropy at this level) is fundamental to identifying the fallacy in this sceptic argument. So somehow you need to weave in the NET element to avoid giving sceptics rope to hang themselves with. (On the other hand....)
  45. Are we too stupid?
    Doug, your nuke car is only missing a flux capacitor. Add a small crane on the back and it would look like it was a Krell design out of Forbidden Planet.
  46. Are we too stupid?
    Two things about that car bother me (I mean, besides whether or not the reactor is given an airbag). First, the designers apparently decided they'd change the polarity of radio broadcasts along w/introducing reactors to the roadways. Second, it looks as though it would be necessary to climb on top of the reactor to retrieve the spare wheel. I mean I'm sure it's perfectly safe even without lead underwear but it looks extremely inconvenient.
  47. Vote for SkS in the physics.org web awards
    Somebody has thought hard how to make a voting system that is as awkward as possible. I voted SkS too, probably. I gave some stars to zooniverse too, as I have been there long time ago classifying some galaxies and lately I have digitized some old weather observations. I suggest that to everyone - this is your chance to do real climate science: http://www.zooniverse.org/home
  48. Waste heat vs greenhouse warming
    Re: archiesteel (287) I believe that may have been RSVP's version of a concession speech...
  49. CO2 is not increasing
    KirkSkywalker, just one of several places you can find details of the problems with Jaworowski's claims is by Jim Easter.
    Moderator Response: Thanks to all three of you for responding to KirkSkywalker's comment. However, in the interests of not diffusing this discussion all over the site, let's redirect any additional comments to the thread where KirkSkywalker first posted on this subject (What does past climate change tell us about global warming?).
  50. CO2 is not increasing
    Make up your mind, Captain Kirk. Elsewhere just a few minutes ago you said the problem w/ice cores is sublimation of CO2, here something different. It's ruinous to your credibility when you spew hypotheses willy-nilly.

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