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Comments 72251 to 72300:

  1. Lindzen Illusion #2: Lindzen vs. Hansen - the Sleek Veneer of the 1980s
    Well, I read the links to see if Charlie A was right in this thread or not. This paragraph seems to be the relevant:
    Nor, he said, was the temperature data collected in a very systematic and uniform way prior to 1880, so comparisons often begin with temperatures around 1880. "The trouble is that the earlier data suggest that one is starting at what probably was an anomalous minimum near 1880. The entire record would more likely be saying that the rise is 0.1 degree plus or minus 0.3 degree."
    If I read that correctly, Lindzen is claiming that the reason the ITR shows warming from 1880 is that 1880 was a local minima. 'The entire record' seems to refer to a fictitious but accurate temperature record going back rather further. His suggestion is therefore that the early 19th C temperatures were rather warmer, and that warming relative to the long term average is therefore rather smaller. My reading may be wrong, but it does look to me as though Charlie has a point: The reconstruction of Lindzen does not reflect what Lindzen is actually saying. Lindzen's claims may be confused and bizarre, they certainly contradict multiple sources of data, but I don't think he is claiming what the graph shows. (Sorry)
  2. Eric (skeptic) at 20:26 PM on 18 October 2011
    Continued Lower Atmosphere Warming
    ...this 'flattening' can be explained by increases in aerosol emissions, decreases in solar activity, and changes in ENSO (the former two of which are not 'natural variability,' but rather are forcings)... Dana, an even more precise description of those three examples is 1) a mostly anthropogenic, but partly natural (varying) forcing, 2) a naturally varying forcing in several modes and 3) a natural variation mostly resulting in ocean-atmosphere exchange but also some forcing. One could look at this paper ftp://128.95.176.42/pub/breth/CPT/cess_jcl01.pdf and conclude that cloud forcings from ENSO generally cancel so they can be disregarded. But the paper shows that over short periods they don't and that is what I and others would call a naturally varying forcing.
  3. Correction to the True Cost of Coal Power - MMN11
    Basically, $50tCO2e gets you all the abatement that is cheaper than $50tCO2e. That's quite a bit, which is why a price on CO2e is a foundational measure and the cheapest way to do abatement. That of course isn't a measure of the true community cost of burning fossil HC, because as I said, the externalities go to much more than AGW. Really, we should err, if we must, on the high side. Let's make it clear that we are moving quickly to $100tCO2e (plus beyond if needed) and see what happens.
  4. Ocean Heat Poised To Come Back And Haunt Us?
    alan - inconsistency is just a sign of immaturity. What does a three year old wear where they're allowed to dress themselves and choose whatever they want? They wear all their favourites. The rubber boots and the beach hat. The rainbow striped socks and the tartan pants. The party jacket over the pyjama top. No account of the obvious fact that there is no relationship of function, colour or pattern. They all look good on their own - so they all go on together. Bit like the intellectual and factual armoury of some rejectionists.
  5. Correction to the True Cost of Coal Power - MMN11
    On the other hand, there'd be positive feedback (in the good sense) from a tax of say $50tCo2e. Because the price signal would affect consumption and push renewables into a very competitive position, many of the other costs associated with fossil fuels would go down (like the risks and costs of transporting the stuff long distances - local supplies would be used first, and be much closer to sufficient). I'm not saying that's the exact right price, but I think we could get to a safe sub-450 ppm peak without needing a price as high as Fran thinks. I'm far from an expert though.
  6. OA not OK part 20: SUMMARY 2/2
    To underscore my point above, Watts has (almost on cue) posted some dog-whistling nonsense that plays Dunning-Kruger bingo with every possible acid chemistry cannard - including the notion that a decrease of about half a pH unit over a century and a bit constitutes "a small change in ocean pH" to which "nature" should be able to adapt. It's enough to reduce to tears anyone with teritiary training in chemistry or biology...
  7. Ocean Heat Poised To Come Back And Haunt Us?
    Good post. The skeptics don’t understand that, like weather phenomena, the long term trend is modulated by shorter-term cycles. And deep ocean heat exchange isn’t the only one. There is also the modulation due to the average 11 year solar (sunspot) cycle – and we are presently at a solar minimum. It seems inconsistent that skeptics can maintain that the sun, rather than CO2, drives climate change, and yet when it suits them, maintain the climate is not changing by ignoring the modulation of the solar cycle. But then, consistency is only required if you want to follow the scientific method.
  8. Continued Lower Atmosphere Warming
    I find it bemusing that Pielke Snr can acknowledge that the post-1998 interval is too short an interval with which to determine (with statistical power) any trend, and then immediately - in the very same sentence, no less - claim that "the warming has halted". This is truly a bizarre stance, and one that implies the action of some sort of cognitive dissonance. Further, Pielke Snr seems to be confabulating planetary warming with perceived plateaux in planetary surface temperature*. The two are separate phenomena, correlated certainly, but not in lock-step. If Pielke Snr has the reference for the work that the planet has in fact not warmed since 1998 (or whenever) I would be most interested to read it. [* I perform a number of polar biology insulation experiments with my students that involve ice baths. These students understand that the ice baths are continuously warming as they sit on a bench, even as the temperature within the baths is not increasing...]
  9. Continued Lower Atmosphere Warming
    Dana @71, Re "Those who live in glass houses". I do not agree with that assessment of what is going on here as it suggests that SkS was indeed ridiculing Pielke. SkS was not doing so, in fact, John H. has said as much and I believe him. I will post more on that thread soon. As for these statements made by Dr. Pielke's post @69: "Your hypothesis that this is just part of the natural variability certain might be correct. It could also mean that the longer terms trend includes a larger natural component than you assume based on the model results. It could mean the other human climate forcings play a larger role than represented in the models. We need to explore each of these issues (and others) rather than being dogmatic and insist the models are faithfully replicating this aspect of the climate system. Also, "By ignoring the obvious (which is hardly "meaningless"), plays into the hands of those you call "skeptics"." It sadly seems that Dr. Pielke is intent on misrepresenting SkS's position, attributing to us positions that we do not hold and engaging in inflammatory rhetoric rather than objective science (e.g., "dogmatic"). Also, I fail to see how Dr. Pielke could have not seen the "flat" trend in the RSS data for 1998-present shown above. Note that the GISTEMP (NASA) surface data (land and ocean) for 1998-present shows a rate of warming of 0.11 C/decade for 1998-present (and we humans live near at the surface not the lower troposphere near 600 mb/14 000 ft). Although I have not tested the statistical significance of that particular trend-- it is still probably too short a period of time for which to derive a statistically significant trend, even for the GISTEMP data. But it does highlight again that one has to use a very particular dataset and for a very particular short-period of time to make the (very misleading) claim that the warming has 'halted'. Dr. Pielke has noted that we humans live on land and that "with respect to the global average surface temperature trend, the land portion makes up a significant portion of it". Well here is what has been happening at the land surface (from NASA)[we are aware of the limitations of the station data and Dr. Pielke has posted about that so there is no need to rehash them again here please]: [Source] Rather than SkS "ignoring the obvious" as Dr. Pielke falsely claims, I would argue that it is the "skeptics" (some who should know better) who are ignoring the obvious regarding the statistical relevance (and power) of their claims when they calculate trends for statistically insignificant periods of time and then make very definitive statements regarding the implications of that trend. Now while continuing arguing in circles may suite some who wish to create the impression that there is a debate, ignoring and dismissing inconvenient facts about statistical tests (and power) is not open for debate. There is a correct way to calculate a statistically meaningful and robust trends from noisy data. And to be quite candid, it was incorrect for Dr. Pielke to choose 1998, and worse yet 2002, as start dates for which to support the claim that "global warming has halted". There are no shades of gray on this. Had such a calculation and attendant claim that "global warming has halted", been been submitted for review in a reputable journal, that portion of the analysis and text would have received harsh criticism and the author/s would have been told to add a very clear caveat that the trend was not statistically significant, but far more likely they would have been instructed to remove the claim as it was not supported by the data in question.
  10. El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
    skywatcher, thanks for that. Am digesting Peterson et al 2008
  11. El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
    I'm not sure I'm the one to try and answer that question. Certainly there seems to be trends in extremes, whether in the oft-quoted trend in US daily record highs over daily record lows, or in Peterson et al 2008. The temperature patterns are consistent with AGW as a cause, ie a rise in maxima, a rise in minima, and in many cases minima rising faster than maxima (along with winters warming faster than summer, nights faster than days) - see the relevant threads on human fingerprints of AGW.
  12. El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
    skywatcher, thankyou for your help. "A warmer atmosphere means that the ENSO extremes are made even more extreme, and relatively more records tuble as a result." Your disclaimer is also well noted. From what I've seen in recent years the extremes are certainly becoming more extreme. What are we looking for to be able to identify AGW as pushing these extremes? Is it a matter of waiting until our data of recorded events extend for long enough to be statistically valid?
  13. El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
    Reprint from 2011, not 2001.
    Moderator Response: [John Hartz]Thanks. Will correct.
  14. El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
    Stevo, I think what you are missing is that a significant El Nino or La Nina represents a relatively extreme distribution of the energy in Earth's system. there's lots of heat in some places, less in others, some areas are particularly dry, others particularly wet. In a world with no warming trend, then extreme events related to heat, dry and wet might be expected to occur relatively more often when ENSO is at one particular end of its cycle, occasionally breaking records. Add in a warming trend, and the extreme events still occur quite often at the endpoints of ENSO, due to the (heterogeneous?) distribution of energy about the earth, conducive to local extremes of weather. However, the extra energy, heat, evaporation, precipitable water etc that is a physical product of a warmer atmosphere means that the ENSO extremes are made even more extreme, and relatively more records tumble as a result.* Not sure if that helps, but it's how I visualise it. For me, the increase in extremes are a product of global warming, but ENSO provides conditions in which you'll more likely see extremes. *disclaimer, I'm not saying all extremes are a consequence of ENSO, or all ENSOs produce large extremes.
  15. El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
    As has been demonstrated on other threads, the frequency and intensity of extreme weather events are on the rise and have been for 15 to 20 years. As some of you have pointed out to me the cause of many of these events can just as likely be sheeted home to ENSO as they can be to AGW. Can someone please help me out on this as I am getting a little confused? How can we explain the increase of extreme weather events if ENSO has not noticably intensified, but the extra water vapour and energy in the atmosphere due to warming can also be put down to effects of ENSO? Surely warming would be the culprit if ENSO is basically unchanged. What am I missing here?
  16. Comparing Global Temperature Predictions
    Thanks for the article, Dana. And I love that animated GIF. Really tells the story. What would help, though, is to put that projected rise to 2100 in context - by, say, including the measured temps from 1900-2000 on the chart as well.
  17. Continued Lower Atmosphere Warming
    Dr Pielke, I refer you back to my figure in #5. In 1985 (or 1994), or any of a number of low points in the record, could it honestly be said that "warming had halted", or that the trend was remotely likely to change, based on the available data? You lose a very great deal of credibility by concentrating on the noise rather than the signal.
  18. Continued Lower Atmosphere Warming
    Roger, You seem to be indulging in an abuse of terminology: - When you say, "The warming has halted," that implies that a warming trend has turned around. - But it has already been established quite clearly that no trend can be established over such short time intervals. So such a claim simply has no meaning. - By analogy, one doesn't claim that the local climate has gone into a local cooling period during the last quarter of the year: It's inappropriate to attempt to define a climate trend over such a short period.
  19. Continued Lower Atmosphere Warming
    Dr. Pielke, several times we have noted that the TLT trend has been essentially flat over recent short periods (which are not statistically significant). We have also discussed that this 'flattening' can be explained by increases in aerosol emissions, decreases in solar activity, and changes in ENSO (the former two of which are not 'natural variability,' but rather are forcings). As for 'ridicule', this is not an activity SkS engages in. And those who live in glass houses should not throw stones.
  20. Pielke Sr. and SkS Warming Estimates
    Well said @Rob Honeycutt, nicely distilled. Sometimes it's easy to miss the grain for all the chaff in the air. Was going to ask what the motivations were from Pielke Sr for arguing on such a point of contention - is it a need for correctness? It seems the motivations for SkS were summed up well by Rob HoneyCutt, though it seems in this thread they have been pretty nicely co-opted in creating more chaff for the doubters to point at (in my [admittedly] humble opinion).
  21. Continued Lower Atmosphere Warming
    Dr. Pielke - "Why not just state that you see this flatness in the data, but have concluded it is part of the natural variability as represented by the climate model predictions" With all due respect, that has been stated multiple times by multiple participants in this discussion, and in fact is a core conclusion of Santer et al. (2011), as linked and quoted in the opening post of this thread: "Because of the pronounced effect of interannual noise on decadal trends, a multi-model ensemble of anthropogenically-forced simulations displays many 10-year periods with little warming. A single decade of observational TLT data is therefore inadequate for identifying a slowly evolving anthropogenic warming signal. Our results show that temperature records of at least 17 years in length are required for identifying human effects on global-mean tropospheric temperature." (emphasis added) To be quite blunt, you are presenting a strawman argument by claiming that others do not recognize the effects of natural variability (they do, which is one of the major points of this discussion), and furthermore contradicting yourself when you "agree it is too short of a record" and then immediately claim "that the warming has halted". I find (IMO) this approach rather disingenuous.
  22. Ocean Heat Poised To Come Back And Haunt Us?
    victull @29 Good question, but there's no way to tell without a lot more info than I have. There's no big change in the standard deviation in the data after about 2001, so whatever goes into that statistic (e.g., improved instrumentation) didn't change much. If they added a bunch of buoys in 2001, and that was it, there would have been a glitch at that point that went away the following year. If they kept adding a few buoys each year for several years, it might skew the data. But after the buoys are all planted, it should settle down again. So the question (to which I don't know the answer) is when they finished, not when they started.
  23. Continued Lower Atmosphere Warming
    I see you have been busy commeting (and presenting q cartoon) while I was on travel and off of the internet. It seems SkS cannot get away without ridicule. :-) Nonetheless, in this first comment since my return, I want to make sure my perspective on the recent MSU lower tropospheric trends is clear. I keep getting asked in the comments why I do not complete a statistical evaluation of the data. The reason should be rather obvious but seems to still not be clear. So here it is. First, I am NOT saying anything about the effect of the lack of warming in the global-annual average surface temperature since 2002 or 1999 (or whatever start year) on the long term trend. I agree it is too short of a record. However, it is trivial in my view (and does not need any statistical evaluation) to see that the warming has halted, with this being clearly seen in the RSS Figure 7 in http://www.ssmi.com/msu/msu_data_description.html#channels. Whenever I show the RSS MSU data (including the lower stratospheric data which you have ingored in all of the comments), no one has raised the objection stating that the data is not ~flat in recent years. In my talks (and you soon will be able to hear the Waterloo talk if you chose) you will hear me highlight that this lack of warming does not tell us anything about the longer term trend. Your hypothesis that this is just part of the natural variability certain might be correct. It could also mean that the longer terms trend includes a larger natural component than you assume based on the model results. It could mean the other human climate forcings play a larger role than represented in the models. We need to explore each of these issues (and others) rather than being dogmatic and insist the models are faithfully replicating this aspect of the climate system. By ignoring the obvious (which is hardly "meaningless"), plays into the hands of those you call "skeptics". Why not just state that you see this flatness in the data, but have concluded it is part of the natural variability as represented by the climate model predictions. Then we can move on to other issues.
    Response:

    [DB] "I see you have been busy commeting (and presenting q cartoon) while I was on travel and off of the internet. It seems SkS cannot get away without ridicule. :-)"

    While it is appreciated that you partake of and enjoy the wide variety of threads available here at Skeptical Science it is recommended that you comment on the threads specific to the core of the above statement. 

    Thus, if you have a probelem with the subject matter of the cartoon in question, it is advised that you take that matter there instead of remonstrating about it here, where it is OT (indeed, please share with us - on the appropriate thread - just specifically how the cartoon in question is ridiculing anyone in specific).  After all, cartoons on blogs are hardly anything new...

    "...it is trivial in my view (and does not need any statistical evaluation) to see that the warming has halted, with this being clearly seen in the RSS Figure..."

    Again you repeat your mantra of the power of visual inspection in lieu of actual analysis.  In that case, I invite you to visually inspect the figures in this comment.

    As someone once said, "You do not need statistics to see the obvious."

  24. Dikran Marsupial at 09:11 AM on 18 October 2011
    El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
    tblakeslee Do not assume that just because a paper has appeared in a journal that it is correct. Be skeptical of all you read. First see if the paper has been cited, and by whom and where. If a paper has been in print for a while (or is one of a sequence of papers along the same lines) but nobody is citing it (other than self-citations) then there is probably a good reason for it. Second ask where it was published, was it published somewhere it would get a competent peer review. Look at the lines of evidence cited in the paper and see if they pan out, follow the references and see what they say. One should always be especialy skeptical of papers that are contraversial, big claims require big evidence. In this case, the paper cites the work of Friis-Christensen and Lassen (1991) on the link between solar-cycle length and northern hemisphere data. However, he doesn't cite the papers that show that the correllation was partially due to errors in the analysis and that as Lassen himself points out the correllation broke down soon after the Friss-Christensen paper was published. Now this was well known by the time Landscheidt wrote the paper, so you have to ask yourself (a) why he didn't mention this and (b) why the reviewers didn't pick it up if they were competent to review a paper on solar-climate links. The Friss-Christensen-Lassen paper is discussed here Secondly ISTR that you mentioned Landscheidt's work earlier and the statistical problems with his work were pointed out then, and yet you have not mentioned that caveat nor addressed them AFAICS. If you want to discuss this sort of solar-climate link, the thread concerned with the Friss-Christensen and Lassen paper would probably be more relevant.
  25. El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
    tblakeslee, your links point to astrological theories about the movements of the planets causing solar cycles. Theodor Landscheidt for example had a book called "Sun, Earth, Man: A Mesh of Cosmic Oscillations - How Planets Regulate Solar Eruptions, Geomagnetic Storms, Conditions of Life and Economic Cycles". Those are the type of sources you think help your case? Really??
  26. Solar Cycle Length proves its the sun
    tblakeslee - In previous threads your hypothesis seemed to be that temperature was controlled by cosmic ray levels, not CO2. Now it's solar cycle length (Landscheidt) and momentum, not CO2? I hate to say it, but I'm seeing a certain lack of consistency here.
  27. El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
    tblakeslee: A paper from Energy and Environment? Really? With regards to the paper's suggested cooling, see here. As far as solar output goes, you should note that 2009 was the second-hottest year on record despite declining solar output.
  28. El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
    tblakeslee - Given your promotion of Landscheidt's theories, and their dependence on information from Friis-Christensen and Lassen (1991), a more appropriate thread for your posts on 'natural cycles' would be the What does Solar Cycle Length tell us about the sun's role in global warming thread. I have replied there.
  29. Solar Cycle Length proves its the sun
    tblakeslee - Note that Friis-Christensen 1991 simply does not hold up due to simple math errors. Landscheidt's theories of cycle length to temperature, based upon that information, are equally unsupported. Once you pass 1970, where CO2 warming really separates from natural variability, and insolation decreases, it becomes extremely clear that the CO2 effects are overriding solar changes.
  30. Comparing Global Temperature Predictions
    Charlie @11, You are still on the wrong thread. I would suggest going to the other thread, reposting your question there and someone will answer.
  31. Antarctica is gaining ice
    # 107 Peter Hogarth Thank you for the response. When you write that there is even less doubt about increasing loss of land based ice in western Antarctica, what do you then base that on? The Zwally paper? Another question, in Zwally the estimated overall ice loss is 31 Gt/year. Could the cause for this be an decrease in precipation over Antarctica?
  32. El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
    "Unaffected by climate change" in the title doesn't make sense. I guess you are equating climate change to CO2. There are natural climate cycles which certainly drive el nino. One obvious driver is the 22 year and 172 year cycles of solar activity caused by the solar tidal effects of the nearby planets. Here is a paper discussing these effects which predicts a 30 year tendency towards la nina has just started. http://multiscience.metapress.com/content/f524m4271487p0u2/?p=d0e5d392df674dd3afb4df2304b3f5e9&pi=9 More info at http://www.landscheidt.info/
  33. An exponential increase in CO2 will result in a linear increase in temperature
    Hi Muoncounter. Yes, I understand the nature of the three curves. The point I was trying to make was that if the real-data plot was distilled to a trajectory representing only the CO2-forced component, would it (or would it not) more closely follow the 3 degree sensitivity, than it does with overlying feedbacks/forcings included?
  34. Comparing Global Temperature Predictions
    @#9 Dana -- you did not address the difference in how you offset the baseline for the various projections. It appears that you used a baseline of 1880 for your interpretation of Lindzen's prediction. Correct? It also appears that you have offset the IPCC projections to match more recently observed data. Correct? What would the Lindzen plot look like if you offset that data using the same adjustment procedure you used for the IPCC projection?
    Response:

    [dana1981] I answered the question in comment #9.  It would be off by 0.38°C in 2010.

  35. Comparing Global Temperature Predictions
    Rob P - thanks, and thanks to jg for making the animation.
  36. Comparing Global Temperature Predictions
    Charlie A, please read the quote in comment #6 and the linked post. It's all explained there. Lindzen effectively predicted 0.01°C warming per decade, so if we ignore half of his incorrect comments (claiming 0.1°C warming from 1880 to 1989), he would have predicted about 0.02°C warming from 1989 to 2011, whereas GISTEMP observed about 0.4°C warming over that period. So Lindzen's would still be off by 0.38°C (in the ballpark of Easterbrook A).
  37. Comparing Global Temperature Predictions
    Dana1981, please explain why Lindzen's 1989 prediction (as interpreted and generated by you) differs from measured global temperature anomaly by about 0.5C, even in the start year of the prediction. If you used the same technique to baseline(offset) your "Lindzen" data in the same way you adjusted the baselines of the IPCC projections, what would your hypothetical 1989 Lindzen prediction be in 1989?
  38. Comparing Global Temperature Predictions
    Great post Dana. I particularly like the animation, as it makes abundantly clear just how wrong the "skeptic" predictions are.
  39. Comparing Global Temperature Predictions
    There were several comments made by Lindzen which went into the reconstruction of what his temperature prediction might have looked like, as explained in the linked post in question.
    "The trouble is that the earlier data suggest that one is starting at what probably was an anomalous minimum near 1880. The entire record would more likely be saying that the rise is 0.1 degree plus or minus 0.3 degree....I would say, and I don't think I'm going out on a very big limb, that the data as we have it does not support a warming. Whether it contradicts it is a matter of taste...I personally feel that the likelihood over the next century of greenhouse warming reaching magnitudes comparable to natural variability seems small"
    In other words, Lindzen was both saying that the surface temperature had hardly warmed (~0.1°C) from 1880 to 1989, and that it would continue to hardly warm (~0.1°C) over the next century. The Lindzen reconstruction reflects both components.
  40. El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
    William, There is a strong correlation between the ENSO cycles and Arctic cloud formation. El Nino increases evaporation which leads to increased cloud formation, which results in warmer winters, but cooler summers, La Nina has the opposite effect. The timing of each is crucial as the possibility exists for both warmer winters and summers, cooler winters and summers, or one warm and one cool. The other factor is the polar vertex. A strong polar vortex leads to reduced sea ice, while a weaker vortex induces sea ice growth. This winter, we are headed towards a weak La Nina, with an expected strong polar vortex, which would result in reduced sea ice this winter.
  41. Warming causes CO2 rise
    @Dikran, ah I think I see where you're going with this. Thanks for taking the time to explain this.
  42. Dikran Marsupial at 06:38 AM on 18 October 2011
    Warming causes CO2 rise
    meznaric, El Nino causes big changes in the terrestrial biosphere around the pacific, so it isn't surprising that ENSO affects CO2. However, the sneaky thing in that plot is that it shows that ENSO changes the rate of change of CO2, not the level of CO2. If you look at a plot of CO2 itself, from Mauna Loa, you see a big exponential increase (due to anthropogenic emissions), an annual oscillation caused by the growth and die back of terrestrial plants (becuase there is more land in the north hemisphere than the south), the variations in the rate of change in CO2 due to ENSO result in the even smaller inter-annual variations on top of that, which are barely perceptable. As the text explains, the differencing operation obliterates the linear trend in the data, which is essentially most of the increase due to anthropogenic emissions.
  43. Warming causes CO2 rise
    @Dikran, OK thanks for that. Having read much of this website, I am quite convinced that what you write is true. But what puzzles me is how do you explain the data in that graph (second from the top)? It's strange that even the El Nino would be in such good agreement.
  44. Dikran Marsupial at 06:04 AM on 18 October 2011
    Warming causes CO2 rise
    meznaric If the natural environment were a net source of CO2 into the atmosphere, then atmospheric CO2 levels would be rising faster than the rate of anthropogenic emissions as both the natural environment and mankind were net sources. However this is not the case, atmospheric levels are only rising at a rate about half that of anthropogenic emissions, which shows that the natural environment is a net carbon sink and takes more carbon out of the atmosphere each year than it puts in. This is one of the relatively few things we know about the climate where we can be certain, beyond reasonable doubt.
  45. El Niño: Unaffected by climate change in the 21st century but its impacts may be more severe
    What is the effect, if any, of both ends of the ENSO cycle on the melting of ice in the Arctic Ocean?
  46. Warming causes CO2 rise
    This Heidelberg stuff is the same silly argument that Beck used in disputing Callendar. When Callendar started collecting CO2 readings back in the 1930s and 40s he found alot which showed a slow consistent upward curve and then a bunch of outliers... all on the high side of the curve and all near major industrial centers. He reasoned that the outliers were due to local emissions which hadn't dispersed throughout the atmosphere yet. Beck argued that they were instead indicative of global changes (even though contradicted by other readings) and should be factored in to show atmospheric CO2 levels roller coasting up and down by huge margins. Of course, Keeling solved this problem in the late 1950s by taking readings at a location (Mana Loa) far removed from any local emissions... and getting results which proved that Callendar's steady curve conclusion was correct. This has subsequently been duplicated at dozens of other isolated sites around the world showing the same results. Arguing that higher readings in industrial areas are thus indicative of anything except the source of the increasing atmospheric CO2 levels is thus clearly specious. You might as well argue that temperature readings taken inside ovens should be factored into global trends... when the oven is off they display massive cooling! Clearly our global warming fears are misplaced!
  47. Comparing Global Temperature Predictions
    KR @3, Indeed, comments policy "No accusations of deception". CharlieA has done this before and is doing it again now. The origin of the offset is clear if one actually invests the time to read the relevant post, something CharlieA has apparently not done. Lindzen has not gone the trouble to make his own projection/s. He loves to berate his colleagues and their efforts to predict what the future holds for a doubling of CO2, but he is either incapable or not willing to make his own predictions. So one has to make a best estimate based on what information Lindzen has volunteered in terms of climate sensitivity and expected temperature change. If one does that, one obtains very little warming for doubling CO2 because Lindzen believes (or has convinced himself) that climate sensitivity is unrealistically low. The huge problem for Lindzen (and his supporters) is that his own arguments have been contradicted by observations-- in fact, his bold proclamation made at MIT in 1989 was wrong the moment he said it. Now if Charlie A has a problem with what Dana did and wants to try and defend Lindzen's refuted claims, then he (and others) can argue that on the relevant thread (link provided by KR), but without suggesting deception. But CharlieA should note the bolded caveats provided by Dana. This post very nicely demonstrates who has had the better track record when making predictions about global temperatures, and it is not the "skeptics" and those in denial about AGW.
  48. Comparing Global Temperature Predictions
    2, Charlie A, It would be great if so called skeptics would actually read and follow links for more detailed explanations (the relevant link is provided in the post above), rather than simply looking at the pretty pictures and jumping to unfounded conclusions (which seems to be pretty much how the skeptical mind consistently works on the subject of climate change -- it's oh so much easier to see what you want to see than to learn and consider the facts). Lindzen's proposal results in ridiculously inaccurate temperature predictions, even back to 1958, because that's how ridiculous his position is. A climate sensitivity as low as his requires that the climate be more stable than has been demonstrated in this entire century, let alone the last 30 years of AGW.
  49. Comparing Global Temperature Predictions
    Charlie A - I would suggest looking at the Lindzen Illusion #2: Lindzen vs. Hansen - the Sleek Veneer of the 1980s, where dana1981 generated a prediction using Lindzen's numbers. Comments might be more appropriate there, with a link in this thread if desired. I will note that (IMO) your comments seem out of line, in that you appear to be accusing dana1981 of fudging the data to make Lindzen look bad.
  50. Comparing Global Temperature Predictions
    Dana, you could make your hypothetical version of Lindzen's predictions look even worse if you moved them down another arbitrary 0.25C or so. Or you could use the same baseline adjustment method you used for the other lines, in which case is would be relatively close to the observed temperatures. It's really a moot point, though, since you are the one that generated the data you claim to be Lindzen's prediction.
    Response:

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