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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 110701 to 110750:

  1. Ocean acidification isn't serious
    I got to wondering if anyone had estimated the numeric relationship between atmospheric CO2 concentration change vs. ocean pH change. The dots in the graph you show suggest the glacial-interglacial difference of 100 ppm corresponded to a pH variation of 0.2 units of pH, so about 50 ppm / (0.1 pH) A bit of searching in Google Scholar yielded: K Caldeira, ME Wickett - Nature, 2003 "Anthropogenic carbon and Ocean pH", cited by 499 http://crecherche.ulb.ac.be/facs/sciences/biol/biol/CaldeiraWickett2003.pdf A key finding of theirs is that large but slow pCO2 changes led to somewhat smaller final ocean pH response, thanks to geologic-scale "buffering" effects (top 1/4 of their figure 1(b)). However, over shorter time spans, "[w]hen a CO2 change occurs over a short time interval (that is, less than about 104 yr), ocean pH is relatively sensitive to added CO2" So, just how sensitive, I wondered? I tried to glean from their graph whether ocean pH response to changes in pCO2(atm) is basically linear or logarithmic (they don't state either way). The X axis of figure 1(b) is log (or semi-log?) while the vertical bands for each pH level are spaced about equally, suggesting a logarithmic relationship. If so, the response for a doubling of CO2 along the bottom of fig. 1(b) (i.e. over short, human-scale time spans relevant to ACC) looks like roughly 0.3 pH units per doubling of pCO2. I'd appreciate if others would review the article and see if my takeoffs make sense of what's there.
  2. A detailed look at climate sensitivity
    CBDunkerson: That makes sense. Thanks for clearing that up.
  3. A detailed look at climate sensitivity
    Werecow, yes the values for 'climate sensitivity' that the article describes are all predicated on the assumption of the current climate. Whatever the 'true' value is would not hold exactly the same after multiple 'doublings' of CO2 over a span of thousands of years. You may notice that most of the paleoclimate studies which attempt to figure out climate sensitivity are focusing on time periods where conditions were relatively close to those we have today. If sensitivity were a constant it wouldn't really matter what time period you looked at. That said, the single largest climate sensitivity factor we have identified is water vapor... and that is tied directly to temperature over a very wide range. Basically, this largest aspect of climate sensitivity wouldn't show significant variation unless the temperature got to the point where all water froze or all water evaporated.
  4. Roger A Pielke Sr at 03:33 AM on 10 September 2010
    Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    robhon - Thank you for your comments. With respect to changing metrics to diagnose global warming, if one elects, the global average surface temperature trend, of course, could be retained. However, we now have sufficiently robust analyses of the global annual average upper ocean heat content (since 2004 according to the experts, such as Josh Willis who work directly with this data) which permits us to adopt it as the primary global warming metric. This metric provides heat in its proper units - Joules, and the difference in heat content between time periods (i.e. the time slices) permits a diagnosis of the global annual average radiative imbalance in units of Watts per meter squared. Comparing the surface temperature trends and upper ocean heat content can itself be informative. In an earlier study Barnett, T.P., D.W. Pierce, and R. Schnur, 2001: Detection of anthropogenic climate change in the world's oceans. Science, 292, 270-274. http://pielkeclimatesci.files.wordpress.com/2010/04/barnett.pdf part of their conclusion reads "Perhaps the most important aspect of this work is that it establishes a strong constraint on the performance and veracity of anthropogenically forced climate models. For example, a climate model that reproduces the observed change in global air temperature over the last 50 years, but fails to quantitatively reproduce the observed changed in ocean heat content, cannot be correct." This was written in 2001 and applies even more so today since the upper ocean heat data is more accurate.
  5. The Little Ice Age: Skeptics skating on thin ice
    This "basic version" is pretty good; I really love the title. But again, as I have said so often, a "basic version" has to avoid the fancy vocabulary that repels the target audience: 'thermohaline' and 'forcing'. It is especially bad that 'forcing' is used with no preparation for the technical sense of the word, which is SO different from the sense the reader is likely to assume -- if he assumes any meaning for the word at all. Also, I would have put much more emphasis, using bold fonts and the like, on "But since WW2 the sun has slowly grown quieter, yet the temperature on Earth has gone up." Such emphasis goes a long way to prepare the reader for the conclusion that the skeptics argument is completely groundless. That, by the way, is what the article should be saying instead of pathetically weak conclusion like, "the skeptical argument... is unlikely". We can say a lot more about it than just 'unlikely'. The skeptical argument is wrong, very wrong. We should say so in no uncertain terms.
    Moderator Response: [Graham] Sorry, but this is the statement that's wrong: "We can say a lot more about it than just 'unlikely'. The skeptical argument is wrong, very wrong". That may be your opinion, but there is no scientific evidence to support it. If there was I'd be more than happy to use it, but in this instance we really must be candid, and admit the uncertainty that pervades this whole issue. Fact is, if the cause and effects of the LIA and MWP were not so equivocal and our knowledge so sketchy, the skeptics wouldn't keep bringing it up. The argument is weak, but so is any rebuttal that relies solely on scientific evidence.
  6. The Little Ice Age: Skeptics skating on thin ice
    Re: Cornelius Breadbasket (4) Many factors are in play regarding temperature balance, with solar activity being just one. If solar activity ramps up and other forcings and feedbacks stay uniform, then yours would be a reasonable assumption. So, yes, you would be correct in that event. But remember that solar forcing, compared to other forcings, is not the main actor on this stage. CO2 is the big dog. If, at the same time, man reduces the quantities of sulfate aerosols injected into the atmosphere (which act to reduce the GHG warming coming from the CO2, then temperatures could rises even more. Factoring in albedo changes in the Northern Hemisphere if, as expected, the Arctic sea ice melts out in the next few years, then expected changes could get very "pronounced". All of these converging together = bad news. Worst case scenario: If on top of all this a methane hydrate/clathrate release initiates... ...then the Earth pinball game goes TILT. What is certain: many uncertainties exist. And we're all in this together. The Yooper
  7. How we know the sun isn't causing global warming
    "solar magnetic field has not changed appreciably over the past three decades" By way of a partial update, see Solar wind loses power, which notes that "the sun's underlying magnetic field has weakened by more than 30% since the mid-1990s". The weaker solar (and hence interplanetary) magnetic field should mean higher incidence of galactic cosmic rays (GCRs) -- which matches observation. GCRs are the high-energy particles that should seed clouds and thereby cool the earth in the Svensmark model. However, we have persistent warming during this period. So weaker magnetic field = more GCRs and warming is indeed 'a nail in the coffin' for this idea.
  8. The Little Ice Age: Skeptics skating on thin ice
    A feature of the Little Ice Age were Frost Fairs on London's Thames, when it froze in the winter. I have heard claims that these were annual occurrances, but they were not, but were quite infrequent and were often of short duration. The last one was held in 1814, and lasted 4 days. Frost Fairs
  9. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    I've been reading this whole exchange with great excitement. It's rather like having a box seat at the big game. We should all thank Dr Pielke for taking the time to post his responses here. Something disturbs me about this notion that Dr Pielke seems to be putting forth that OHC should supplant global temperature readings as a proxy for global warming. Please correct me if I have that wrong. When he says "global warming has halted" based on OHC measurements I read a rhetorical leap that may not yet be justified. I believe I understand that OHC should be a better metric being that such a larger volume of the actual energy is resident in the ocean. But it's also strikes me as an act of changing the rules of the game at half time. It's almost even like saying, "Well, we've been playing football the first half, but really baseball is a much better game so let's play that the second half." The part that makes me suspicious of this attempt to change the game is that, while baseball might be the better game, it sounds like we're still figuring out how to build baseball mitts and bats, and measuring how far apart the bases should be. The uniforms aren't yet even stitched up and we're making grand statements about the score? Is the ARGO buoy network really robust enough to completely change how we define climate change? Think back 20 years ago. Where were we with satellite readings? We had big battles going over the UAH reporting cooling while ground stations were reporting warming. Right? There were a lot of kinks to work out to get to the understanding of atmospheric temperature we have today. I don't want to jump to conclusions about any ulterior motives that Dr. Pielke might have in this. I accept that he is an upstanding scientist, just as the others opposing him here are also upstanding scientists. Each scientist is still human and has personal motivations. From my box seat I would suggest it's a mistake to make the rhetorical leap in referring to OHC as "global warming." If baseball truly is the better game, get all the gear and all the rules right first, then change the game. In the mean time, be careful with your words. The stands are full of very rowdy fans.
  10. Cornelius Breadbasket at 02:38 AM on 10 September 2010
    The Little Ice Age: Skeptics skating on thin ice
    What is really worrying is that solar activity has been so quiet since 1950, yet temps are still increasing. This implies that once solar activity starts up again, global warming will speed up - is this right?
  11. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    RSVP, the mechanisms by which the atmosphere heats the ocean certainly are known. For example, a Google search for "heat transfer from atmosphere to ocean" returns a Columbia University class lecture page, which explains that conduction and radiation do that. Regarding radiation:
    "The infrared radiation emitted from the ocean is quickly absorbed and re-emitted by water vapor and carbon dioxide and other greenhouse gases residing in the lower atmosphere. Much of the radiation from the atmospheric gases, also in the infrared range, is transmitted back to the ocean, reducing the net long wave radiation heat loss of the ocean. The warmer the ocean the warmer and more humid is the air, increasing its greenhouse abilities. Thus it is very difficult for the ocean to transmit heat by long wave radiation into the atmosphere; the greenhouse gases just kick it back, notably water vapor whose concentration is proportional to the air temperature."
  12. A detailed look at climate sensitivity
    Figure 1 displays temperatures for two Antarctic sites. I think it might confuse readers that they are called "global" in the caption.
  13. A detailed look at climate sensitivity
    Also the link to Knutti & Hegerl 2008 is broken (there'a %20 tagged on at the end).
  14. The Little Ice Age: Skeptics skating on thin ice
    Re: doug_bostrom (2)
    "Nobody on the Internet would be wrong, if we were all bachelors."
     If we were all bachelors we wouldn't be on the Internet. Catch-22. Nice post Graham! You may want to reiterate that, while the LIA was an intensely "personal" event to those in Northern Europe, there is a lack of evidence to extend its effects to the rest of the globe (thus no "global cooling" during the LIA). The Yooper
    Moderator Response: [Graham] Thing is Dan, when we lack evidence - and this applies to the MWP as well as the LIA - introducing the global argument serves to muddy the waters, and may be construed as over-egging the issue. A lack of evidence is not grounds for suggesting further problems with the skeptical argument in my opinion.
  15. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    NETDR wrote : "A 5 year pause cannot happen if Catastrophic AGW is real." It would depend on what 'Catastrophic AGW' is. What does that mean ?
  16. A detailed look at climate sensitivity
    I've been wondering about this for a while, but doesn't climate sensitivity depend on your initial conditions to some degree? For example, if you start of with a positive forcing under glacial conditions, you need to take into account ice albedo feedback. On the other hand, if you start of in hothouse conditions where no significant ice caps exist, it seems that the same forcing would not be amplified in the same way. Am I missing something, or is it just that we focus on sensitivity under conditions comparable to those of today?
  17. The Little Ice Age: Skeptics skating on thin ice
    Chris: And my wife has soundly taken me to task for hanging round the blogosphere at 1.30 am when I'm meant to be finishing a psych report :-) Nobody on the Internet would be wrong, if we were all bachelors. :-)
  18. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    All, My last post on this. I would encourage everyone concerned to read the summary on global OHC by Palmer et. al (pages 60-61)in the "2009 state of the climate report"
  19. How we know the sun isn't causing global warming
    Ned @ 19 summed it up well. Yes, there are nuanced solar influences which can impact local temperature and weather, but the Sun is not responsible for the long-term increase in the average global temperature. It's important to distinguish between not understanding all solar effects and understanding the big solar effects. As for the format of the article, there's a reason I linked to the Intermediate version at the beginning. It has a very thorough list of peer-reviewed studies on the subject, and in fact that's primarily what it's devoted to. Thus it doesn't make sense to also devote the Advanced version to a long list of peer-review references. Instead I thought it would be a worthwhile endeavor to go through how the solar radiative forcing is calculated so that people can see the numbers for themselves. It's all well and good to read the IPCC's range of possible solar forcing values, but personally, I like to go through the calculations myself. And I think that's appropriate for an 'Advanced' rebuttal.
  20. How we know the sun isn't causing global warming
    Thanks for clearing up an urban myth Ned (that's the crisis and opportunity one). As an interesting aside, there's a similar confusion around the Greek word 'stasis' which today we use to mean 'coming to a halt' but to the ancient Greeks meant a political crisis (no - I'm not showing off my non-existent erudition in classical Greek - my 21 year old son is the seriously bright Greek scholar who is now dipping into Mandarin!). Plate tectonics is fascinating. In Darwin's 'Voyage of the Beagle,' there's a fascinating description of major earthquake in South America - Darwin speaks of a big chunk of land rising. Darwin can't explain it but notes the phenomenon. I recall reading his description and having a huge 'Aha' moment - Darwin had just observed a shift which to a modern observer is all too obviously plate tectonics at work. So actually, the evidence for plate tectonics today is a little bit more than circumstantial. Indeed, we can measure its operation. Darwin's by contrast explained the phenomenon he observed in terms of volcanism (if my memory serves me correctly) citing the apparently near simultaneous eruption of a volcano some many (but not too many) miles away. In fact, of course, we recognise today that volcanic activity has heaps to do with plate tectonics. So Darwin proved was working on a good hunch - he just didn't know how to integrate the information because he didn't have all the bits of the jigsaw. I definitely don't reject evidence just because it's circumstantial - I merely argue for greater caution as would any defence barrister. But I don't hold a 'brief' for 'scepticism' even if my mind tends that way.
  21. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    Re Daniel Bailey [59] As I stated earlier Did anyone post that the Atmosphere was cooling at the same time that the oceans were cooling according to both the GISS and UAH satellite temperature readings. http://www.woodfortrees.org/plot/uah/from:2005/to:2009/plot/uah/from:2005/to:2009/trend So the heat isn't in the oceans and it isn't in the atmosphere, where did it go ? To the Lithosphere ? I doubt it. ****** The charge of cherry picking is inadequate because if the measurements are correct, which is an issue which has been addressed elsewhere heat cannot leave the system for a 5 year period. It could go between the atmosphere and the oceans and back again due to El Nino's and La Nina's but it must keep increasing. A 5 year pause cannot happen if Catastrophic AGW is real. When huge positive feedback is shown not to be happening currently the defense is that the heat is being stored in the oceans to come back and cause rapid warming later. If it hasn't been stored during a 5 year period the rapid warming probably won't happen. No cherries involved if the data is correct.
  22. The Little Ice Age: Skeptics skating on thin ice
    This is a fascinating follow up from dana1981's post. The C14 data cited show a solar activity level just around 1950 that is greater than that of the putative mediaeval warm period. If we go back to dana's post, we find a graph taken from Lockwood (2001) which shows maximum coronal source flux in the mid 1990s 1.5 times greater than the 1750 maximum. Lockwood's paper is rich in data - the abstract says coronal source magnetic flux had risen 34% since 1963 and 140% since 1900. If I understand her correctly, flux is a good measure of TSI. Her 10Be isotope data which she says is also a good proxy for flux suggest peaks in 1500 with a trough around 1520 and a huge trough in 1700. 10Be peaks dramatically around 1950 as best as I can make out from her graphics. I'm not quite sure how her data translate into the current decade with its 'quiet' sun. Alas, I haven't yet mastered (and probably never will) the art of posting links and graphics but then I always was a technological dinosaur :-( But I would be interested if anyone wanted to have a closer look and see how these data play out in the overall picture. And my wife has soundly taken me to task for hanging round the blogosphere at 1.30 am when I'm meant to be finishing a psych report :-)
  23. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    Excellent rephrasing, MrJon!
  24. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    GPWayne @77, Well stated. I was going to address comments made by HR directed at me, but what is the point? They and Pielke have made up their mind, you and I and others have made up ours based on the data and caveats associated with such data, and thought son this matter by experts working closely with the data (Lyman, Tremberth, von Shuckmann, Levitus, Willis etc.) It would have been nice to say at the end of this exchange that Pielke Snr recognized and acknowledged what he said on OHC (and other climate metrics) was misleading and perhaps even revised his public statement/s on those issues. But sadly other, less scientific, factors seem to be standing in his way. All I will say to HR regarding his/her comment: "Really, enough of the morality tales! Stick to the science." First, those two points are not mutually exclusive. Second, maybe your second sentence should be directed at Pielke Snr and not me and others here (and elsewhere) who have (with very good scientific reason) criticized Pielke.
  25. How we know the sun isn't causing global warming
    It's said that the Chinese use the same character to represent 'crisis' and 'opportunity.' And apparently, one Chinese curse goes, 'May you live in interesting times!' The "crisis" and "opportunity" thing is a bit of a misunderstanding, at least as most Westerners use it. The words for "crisis" (wēijī) and "opportunity" (jīhuì) both incorporate the character "jī" but it doesn't really convey any sense of connection between the two. "Jī" is combined with lots of other characters to make bisyllabic words with all kinds of different meanings. Bringing this back within hailing distance of the topic of this site, Al Gore unfortunately repeated this fable about "crisis/opportunity" on a couple of occasions in speeches about climate change. For example, from his 2007 speech accepting the Nobel Prize:
    In the Kanji characters used in both Chinese and Japanese, "crisis" is written with two symbols, the first meaning "danger," the second "opportunity."
    So, chriscanaris, you've got good company on that one!
  26. How we know the sun isn't causing global warming
    chriscanaris: I know I make this comparison a lot, but climate change is very similar to plate tectonics in a lot of ways, one being the importance of "multiple converging lines of evidence." Both theories seek to explain very slow planetary-scale processes that can't be completely replicated in the lab and that aren't amenable to the traditional controlled-experiment that people in certain other fields get to use (there's only one Earth!). Thus, both theories rely on modeling, observational studies ... and multiple converging lines of evidence. We all accept plate tectonics (I hope), but some are reluctant to accept anthropogenic climate change. Of course, it's possible that in this case the particular lines of evidence for climate change are individually or collectively not as impressive as those for plate tectonics. Alternatively, one could speculate about other reasons that would explain people's willingness to accept one theory while rejecting the other, but I'd prefer not to wander that far off-topic. My point is just that we don't generally object to the reliance on "multiple lines of evidence" in principle, when it comes to complicated theories about planetary-scale physical processes.
  27. A detailed look at climate sensitivity
    Daniel Bailey (#25) said "in order for the air to hold increased moisture over time it must have warmed." True for an ideal situation (the C-C relationship), but certainly does not hold for a global average. If that global average increased moisture is evenly distributed then the world must be warmer on average. If not, then not necessarily depending on how uneven water vapor is (as a whole, not just the increase). This is an very common misconception here, and your second point is a good starting point: "Water vapor acts as a feedback to the warming". How? By absorbing and emitting IR, some of which returns downward. The distribution of water vapor is what determines the amount of GH warming from WV. There is more GH warming from WV on average if WV increases on average. But that is only true if the distribution of that WV stays the same (meaning weather stays the same on average). There are many threads here insisting that weather is changing and that the distribution of WV is more highly concentrated (increased precipitation extremes as one common example). When WV is highly concentrated, the areas with greater concentration reach saturation for IR absorption. The areas with less have less absorption than if the WV were more evenly distributed. The result is less warming (sensitivity) than if the weather remained constant with the increased warming from CO2.
  28. How we know the sun isn't causing global warming
    All the citations of Haigh are interesting... in that Haigh herself has said that it is disingenuous to claim that her work suggests recent warming has been caused by the Sun. Yes, the Sun has important impacts on climate. No, it isn't causing the recent warming.
  29. Roger A Pielke Sr at 00:30 AM on 10 September 2010
    Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    JMurphy - Our paper on siting quality issues with respect to multi-decadal surface temperature trends is nearly complete. On other climate metrics, such as sea ice, sea level, etc, they all support climate variability and longer term change. There clearly is a significant human influence (e.g. black carbon deposition on Arctic sea ice), but the natural variations remain incompletely understood (for example, we cannot skillfully predict more than a season at most into the future regional circulation features such as the NAO, the PDO and ENSO). The annual global average OHC is just one climate metric. Indeed, it tells us nothing about these regional atmospheric/ocean features (although the regional OHC data does). The annual global average OHC, however, is the most accurate way for us to diagnose the global annual average radiative imbalance, as I discussed in the paper Pielke Sr., R.A., 2003: Heat storage within the Earth system. Bull. Amer. Meteor. Soc., 84, 331-335. http://pielkeclimatesci.wordpress.com/files/2009/10/r-247.pdf I also recommend interested readers of this weblog look at the paper Ellis et al. 1978: The annual variation in the global heat balance of the Earth. J. Climate. 83, 1958-1962. http://www.climatesci.org/publications/pdf/ellis%20et%20al%20JGR%201978.pdf Finally, Bill Cotton and I completed a book Cotton, W.R. and R.A. Pielke, 2007: Human impacts on weather and climate, Cambridge University Press, 330 pp.http://www.cambridge.org/catalogue/catalogue.asp?isbn=9780521600569 which I recommend if readers would like a more in depth perspective of our conclusions on climate science. I also recommend my son's book The Climate Fix: What Scientists and Politicians Won't Tell You About Global Warming (Basic Books) http://rogerpielkejr.blogspot.com/2010/04/climate-fix.html whose recommendations I agree completely with.
  30. actually thoughtful at 00:29 AM on 10 September 2010
    Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    RSVP: "Normally, oceans are seen to directly influence air temperatures and not the other way around." Thank you for that reminder - that is one point of data that shows our OHC accounting is probably not robust yet. If 90% of the world's heat content is in the ocean, and oceans affect air temp (and not the other way around) AND air temps are rising (which they are): Then OHC is rising - which is what folks like Trenberth seem to suspect. (I understand it is more complicated than that - RSVP's comment just turned on a lightbulb for me on thinking about the "missing" OHC.
  31. How we know the sun isn't causing global warming
    Ned: I think the migratory bird analogy is actually a very good one. I might take it further. Some birds get lost and end up in strange places. This probably means little in the scheme of things. When whole populations go off course, it probably means an awful lot. Which brings to mind John Cook's 'meme' of multiple converging lines of evidence one of which I think includes changing population distributions in various species. I'm going off topic but here, I have to confess to having a philosophical difficulty with the multiple converging lines of evidence notion - not because it lacks validity but because it's 'circumstantial' evidence. Of course, you can still get a jury to convict an offender if the circumstantial evidence is overwhelming. However, circumstantial evidence of its nature demands more rigorous testing. This rather than a wish to 'deny' AWG prompts the 'sceptical' undertone of many of my comments. Of course, I'd rather not see the temperature go up 6 degrees C in 2100. However, my wishing that it wouldn't won't alter the outcome if we have indeed messed up our planet (and continue to do so). So I maintain a keen interest in the debate watching how it plays out. A very recent interesting twist in all this seems to be that the Chinese in their usual 'subtle' approach to matters economic have reportedly just ordered a clamp down on greenhouse emissions - a big short term worry for Australia which has for better or worse hitched its economic wagon to Chinese demand for our coal and iron. It's said that the Chinese use the same character to represent 'crisis' and 'opportunity.' And apparently, one Chinese curse goes, 'May you live in interesting times!'
  32. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    Could we not put this issue to bed by rephrasing the catchy, if contested statement: 'This means that global warming halted on this time period.' With a somewhat less pithy but probably more informative: 'Taken at face value the NODC data clearly show a lack of warming over the four years commencing 2004, however the short term nature of the trend, the uncertainty in the accuracy of the data and its inconsistency with numerous other lines of evidence mean that this has little to say about the wider science and story of anthropogenic climate change. However were the trend to continue for longer and the data shown to be an accurate reflection of the actual situation then it would be of great importance.'
    Response: Yes, but can you tweet that? :-)
  33. Roger A Pielke Sr at 00:01 AM on 10 September 2010
    Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    Ken Lambert - Thank you for your thoughtful comments. My statement below, however, is correct (and I agree with you that simultaneous measurements are optimal). As I wrote (and you reproduced) "Roger Pielke Sr wrote "There does not need to be years of record to obtain statistically significant measures of upper ocean heat content. This is the point of using heat. We just need time slices with sufficient spatial data. A trend is unnecessary." The concept of "time slices" is precisely what you have very clearly expressed; "To measure the global OHC content in Joules (call it J1) at time T1 is only meaningful if you then measure it again (J2) at time T2 (probably exactly 1 year later at 1200 hrs GMT). The difference J1-J2 would be the positive or negative OHC change in Joules/year. Heat energy (Joules) divided by time (1 second) has the same unit dimensions as a Watt which is the unit of power or energy flux (called 'forcing' by non-engineer climate scientists)." My only addition to your summary is that the statistical robustness would be improved by more frequent (say monthly slices) in order to resolve the annual global cycle of warming and cooling that is seen, for example, in Josh Willis's analysis in my Physics Today paper.
  34. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    Gpwayne - I must completely agree with this post on equivocation, and your followup comment here. Dr. Pielke - Your statements certainty are simply unsupportable in light of the data quality. If you make statements as as strong as "...global warming halted on this time period" based upon 5 years of data, you are cherry-picking, and I'm disappointed to see such behavior coming from an accomplished scientist such as yourself. The ARGO data is an excellent measure, but it is not perfect in spatial coverage, in temporal noise, or most certainly in analysis. 5 years is too short a time period to make unqualified statements from that data stream. If your snapshot is noisy, you need to take multiple snapshots before drawing conclusions. Following some of the other comments on this thread, I've also seen your rather unqualified statements based upon short time series regarding sea level rise, ice levels, and surface temperatures. While I'm hesitant to guess at motivations, it certainly appears from these incidents that you are (repeatedly) willing to use a statistically unsupportable cherry-picked data subset to score rhetorical points against efforts to mitigate human-caused global warming. You seem to have done some interesting work on ground cover and it's climate implications, and I'll continue to read those along with other sources. But, Dr. Pielke, I'm afraid I cannot trust your conclusions to be unbiased, or even solidly based upon your data. And I'm very sorry to have to say so.
  35. Is climate science settled? Especially the important parts?
    RSVP, this is what I mean about not living in a world of certainties. For climate modelers to be able to do what you suggest, they’d have to exactly quantify the various feedbacks and time-lags at each stage of the process. I don’t think it’s reasonable to expect that from science. However, the IPCC does model the range of possible temperature rises for a range of possible emissions scenarios (the scenarios having been defined in a previous report). See this page from the Summary for Policymakers. Under the best-case B1 scenario, global temperatures are projected to rise 1.1-2.9°C. In the worst-case A1FI scenario, the temperature rise is 2.4-6.4°C. The large error bars are because of lingering uncertainties to do with cloud feedbacks and so on. The same table also includes numbers for sea level rise as well, but bear in mind these do not take into account the contribution from ice sheets. More recent models which do include ice sheets predict around one to two metres of sea level rise over the next century. Projecting future climate change is probably the most uncertain aspect of climate science. But I would still argue that these uncertainties shouldn’t be used to justify inaction. The prognosis might well be better than we currently think, but it is equally likely to be worse than we think.
  36. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    HR #70 and #74 Well stated HR. Albatros is stretching a very weak argument to breaking point. Of course Argo is vastly better than what preceeded it in terms of coverage and accuracy - but it still is sparse in large areas of ocean and I would suggest as I already have in an earler post #17 on this thread that the 'gold standard' for OHC measurement would be a system of tethered buoys which measured the same 'tile' of ocean all the time T1, T2, T3 etc. ie: "How close the drifting Argo come to the 'ideal' is hard to determine. For sure, strong currents will tend to coagulate drifting buoys so that the same 'tile' of ocean might might not be measured at time T2 as was measured at T1. Two or more buoys might enter a tile of ocean and leave none where a prior measurement was taken." Although I support Dr Pielke's general conclusions about the lack of OHC increase since 2003-4 which is 6-7 years - and therefore its direct relationship to a 'lack' of warming imbalance by CO2GHG forcings, Dr Pielke certainly has made a confusing statement here as restated by Tom Dayton at #54: 54.Tom Dayton at 09:40 AM on 9 September, 2010 Roger Pielke Sr wrote "There does not need to be years of record to obtain statistically significant measures of upper ocean heat content. This is the point of using heat. We just need time slices with sufficient spatial data. A trend is unnecessary." This is wrong unless the "time slices" are over several years. To measure a global change in OHC you need a global snapshot at time T1 to set a baseline and then snapshots at times T2, T3 etc to measure the change from T1. I think that Dr Pielke might be confusing the total energy with the rate of energy accumulation. To measure the global OHC content in Joules (call it J1) at time T1 is only meaningful if you then measure it again (J2) at time T2 (probably exactly 1 year later at 1200 hrs GMT). The difference J1-J2 would be the positive or negative OHC change in Joules/year. Heat energy (Joules) divided by time (1 second) has the same unit dimensions as a Watt which is the unit of power or energy flux (called 'forcing' by non-engineer climate scientists). As we can easily calculate, a 'forcing' of 1.0W/sq.m of the Earth's surface equates to about 160E20Joules/year of heat energy gain or loss to the planet. Dr Pielke should clarify this point and perhaps comment on my suggested 'ideal' gold standard OHC measurement system of globally tethered buoys all reporting at the same time. (Post #17)
  37. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    gpwayne wrote : "unqualified claims that global warming has not been occurring on the basis of contested ocean temperatures alone are highly misleading, and the certainty of the statement is both inappropriate and unscientific." To me, that seems to be the biggest criticism of Dr Pielke Sr and I think he has quite a history of cherry-picking short periods with regard to other metrics. For example : "Sea level has actually flattened since 2006" "Their has been no statistically significant warming of the upper ocean since 2003." With regard to Arctic sea ice : "Since 2008, the anomalies have actually decreased." These can all be seen on Dr Pielke Sr's blog (from the middle of last year). There is also this from 2008 : The focusing on global warming as the reason for any hurricane (or making it more likely to occur or become more intense) ignores that natural variations are not only more important than indicated by the AP news story, but also that the human influence involves a diverse range of first-order climate forcings, including, but not limited global warming [which, of course, has not occurred since at least mid-2004!]. Again at his blog. There is also interesting information from the talk that Dr Pielke Sr gave last year to a gathering under the auspices of the George Marshall Institute, including : Lower Troposphere The warmest time period was during the big El Niño in 1998, but if you look at the period from, say, 2001 to the present, if anything it is slightly falling. It is certainly not rising. But you notice that since about 1995, if you put a linear plot since then, there has basically been no further cooling of the stratosphere. [ARCTIC ICE LEVEL] has recovered, so it is higher than it was this time last year, for example. Antarctica, for the last number of years, actually has been increasing in its sea ice cov-erage. There are some that are trying to suggest that this is also consistent with a warming planet and a warming Antarctica. I find that concept hard to grasp. The problem is that the climate hasn’t been warming over the last number of years. There certainly are changes over time which again shows that climate is variable and we can’t just talk about one single metric like the global average temperature, for example. Anthony Watts has written a very influential and carefully put-together report, Is the U.S. Surface Temperature Record Reliable?, which came out of a Heartland Insti-tute meeting, held a few months ago. What Anthony Watts has done (and we are working on a paper with him on this for publication soon) is document how many sites are well located and how many are poorly located Any further information on that paper ?
  38. A detailed look at climate sensitivity
    Re: Eric ("skeptic") @ 24
    "BTW, proving that humidity has gone up on average means nothing. The distribution of water vapor is the only thing that causes or doesn't cause global warming. If water vapor is evenly distributed then there is global warming, if not, global cooling. There is a large natural range encompassing both cases and a lot in the middle."
     You are in error. 1. As my earlier link clearly shows, global humidity anomalies have increased since 1970 (by about 4%, the equivalent volume of Lake Erie of the Great Lakes). As humidity levels in the air normalize within nine days (excess precipitates out while evaporation "refills the tanks"), in order for the air to hold increased moisture over time it must have warmed. Multiple global datasets show this warming. Look it up. 2. The GHG effects of CO2 work their stuff in the upper troposphere, above the major concentrations of water vapor in the lower troposphere. Water vapor acts as a feedback to the warming impetus caused by rising levels of CO2 concentrations (forcings). This is all basic stuff (the physics of greenhouse gases are very well understood). Look it up (keywords: back radiation). Ample resources for education on both points exist on Skeptical Science. And on many other reputable websites. Pour the coppers of your pockets into your mind and your mind will fill your pockets with gold: Real Climate: Start Here The Discovery of Global Warming Richard Alley's talk: CO2 is the biggest control knob The Yooper
  39. How we know the sun isn't causing global warming
    chriscanaris writes: The preceding paragraph is also important: [...] Agreed. I think this ties in with my two questions above. In the paragraph you quote, Lean is making the case for what I identify as "question 1". In other words, "Yes, the sun plays an important role in climate, and there are a lot of things that climate models won't be able to get right without accounting for that!" chriscanaris continues with the disclaimer: This does not, repeat not, mean, 'Great, lets burn more coal folks!' Understood, and appreciated.
  40. How we know the sun isn't causing global warming
    chriscanaris, your "macroeconomic / microeconomic" analogy is probably a good one but for some reason I'm not quite getting it. I think we need to be careful to differentiate among various possible questions. (1) Does solar variation have any significant effects on climate? A lot of the material in both Haigh 2007 and Lean 2010 (both of which are fairly long review articles) is about demonstrating the influence of solar variations on aspects of the climate system. And they both convincingly document those influences. If you're a climate modeler, you want to understand those effects. If you're trying to evaluate changes in the climate system among periods when the sun has been more vs less active, you want to understand those effects. (2) Does solar variation "explain away" the multidecadal observed warming trend (say 1975-present)? The question addressed in this thread here at SkS (and in Raypierre's "nails in the coffin" quote) is different, and I think more directly focused on the concerns of skeptics vis-a-vis climate change. The answer to this question appears to be pretty clearly "No, solar variation doesn't explain the underlying warming trend over the past three or four decades". The warming has now continued across multiple solar cycles. Insofar as there is a long-term trend outside of those cycles, we'd expect the sun to be promoting slight cooling rather than warming in recent decades. For a different analogy, consider some kind of migratory animal, like a sandhill crane or something that's heading south for the winter (it's that time of year here in the northern hemisphere...) There is an underlying impetus to keep heading south as winter approaches. But superimposed on that southward migration, the bird moves around its local vicinity in search of food, places to roost for the night, its fellow cranes, etc. So you can't understand the actual movement of this bird without considering the factors that cause the crane to go a little bit east today, and a bit southwest tomorrow, and then north the following day. But those factors (the bird's immediate needs) don't explain why after a period of a month or two it's hundreds or thousands of km south of where it started. OK, maybe your macro/micro economics analogy is better. But at least I think this is a more useful "bird" analogy than BP's dropping some kind of bird out of the leaning tower of Pisa!
  41. How we know the sun isn't causing global warming
    The preceding paragraph is also important: 'Dismissal of Sun–climate associations was, until recently, de rigueur because climate models were not been able to replicate them. But the increasingly extensive, broadly self-consistent empirical evidence accruing in multiple high-fidelity datasets of present and past climate, combined with new appreciation of the complex mechanisms, now precludes this. Climate models are instead challenged to reproduce this comprehensive empirical evidence.' This does not, repeat not, mean, 'Great, lets burn more coal folks!'
  42. How we know the sun isn't causing global warming
    Judith Lean has another recent paper on this subject: Lean 2010, Cycles and trends in solar irradiance and climate, Wiley Interdisciplinary Reviews: Climate Change, 1: 111–122. The one-sentence quote that captures its point: Although solar irradiance cycles impart only modest global mean surface temperature changes (of ∼0.1°C), they are nevertheless sufficient to alter climate ‘trends’ on decadal time scales and must therefore be understood and quantified for more reliable near-term climate forecasts and rapid detection of the anthropogenic component to aid global change policy making. In other words, looking forward, at decadal time scales the solar cycle will tend to produce an oscillation in global temperatures that is superimposed on the underlying anthropogenic warming trend. Over the course of each solar cycle, this will alternately amplify the underlying anthropogenic warming trend for a few years, then retard it for a few years.
  43. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    gpwayne @ 77 - I concur, all I've seen so far are smoke bombs.
  44. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    HR @ 74 "The poorest data, as expressed in AchutaRao et al. 2007, can be found in the pre-ARGO data yet you maintain your strongest critisism for the data quality in the ARGO period." HR, the ARGO network is not without it's problems either, pressure sensors are failing in a number of floats: Two micro-leak defects leave some 25-35% of the Argo floats deployed between 11/2005 and 7/2009 vulnerable to errors in reported pressure and possible eventual failure Seems to be typical teething problems with new technology.
  45. How we know the sun isn't causing global warming
    However, Ned, I do think we ought to go back to Haigh's 2007 paper where she argues inter alia: 'Thus a better estimate of radiative forcing to solar irradiance changes should incorporate the effects of the influence of variations in UV on stratospheric temperature and composition (as first noted by Haigh, 1994).' This seems to be one divergence between dana1981 and Haigh who further writes: 'Recently an atmosphere-ocean GCM with fully coupled stratospheric chemistry has been run (despite huge computational demands) to simulate the effects of changes in solar irradiance between the Maunder Minimum and the present (Shindell et al., 2006). As in the previous studies the results show a weakened Hadley circulation when the Sun is more active, and they also suggest an impact on the hydrological cycle with greater tropical precipitation. Furthermore, they provide additional evidence that coupling with stratospheric chemistry enhances the solar signal near the surface.' Moreover: 'There is some observational evidence that variations in the strength of the polar vortex in the upper stratosphere may subsequently influence surface climate. A study of polar temperature trends by Thompson et al. (2005) suggests a downward influence, and modelling experiments by Gillett and Thompson (2003) demonstrate that depletion of stratospheric ozone over the south pole can affect the troposphere after about one month. Neither of these studies is specifically concerned with a solar influence but the accumulating evidence suggests that any factor influencing the strength of the polar stratospheric jet may be able to influence surface climate, at least at high latitudes.' I don't want to turn this into a quote mining exercise. To be perfectly honest, evaluating the claims and reconciling the seeming divergence between two thorough looking summaries of the literature, ie, dana1981 and Haigh (2007) is beyond me. But I'd be interested in hearing what others think on this score. As best as I can tell, Haigh seems to be saying that the sun keeps doing things to climate (or 'weather' if you prefer) at, to use an analogy from another discipline, the 'microeconomic' level while the papers cited in dana's response to omnologos seem to make a 'macroeconomic' assessment. I guess the question then is, is it valid to brush aside the microeconomic perspective or does this risk detracting substantially from our the macroeconomic perspective? Bear in mind that earlier posts have alluded to numerous sensitive feedbacks that go way beyond CO2 rises as causes for concern (eg, CH4 clathrate release and the like).
  46. How we know the sun isn't causing global warming
    regarding the response to #13 So the Advanced Version contains fewer references than the Intermediate one? Go figure!
    Response: I guess my intermediate version is a broadbrush approach - just listing just about every paper on the topic with a single quote, while the advanced version picks a few papers to go into more indepth analysis. Then the basic version is the cliff notes version :-)
  47. Climate and chaos
    As far as I can tell, BP's contributions to this thread consist of the following: * A lot of fish died in Bolivia. * Something unclear about a "birdie" dropped from the leaning tower of Pisa. The point of the first comment seems to be that the fish might have died because it was cold, and if it was cold in Bolivia recently then global warming isn't occurring. Or something like that. I have no idea what the point of the second comment is. Perhaps it's an attempt to illustrate the subject matter of this thread (chaos) by randomly posting irrelevant remarks and seeing where the discussion goes?
  48. How we know the sun isn't causing global warming
    Ned @ 11 Fair point :-)
  49. Climate and chaos
    By birdie do you mean something to do with golf? A model for predicting ball location based mostly variation of angle of strike and force? Okay, so there is wind and bounce too but this doesnt seem either difficult nor to involve an dynamical system theory either. Of course the theory wont help you get one...
  50. A detailed look at climate sensitivity
    scaddenp (#11): my mantra is "all climate is local". There is no such thing as "messing an average" since the average is a function of all the locals. The satellite shot I showed may indicate some local uneven distribution of water vapor (at least in N. America and adjacent Atlantic right now), but that unevenness is NOT balanced by some evenness somewhere else to produce an average. If there is more unevenness elsewhere then the world is cooling, period. Tomorrow it might even out and we will have global warming. What happens is entirely up to the local weather. Your appeal to models falls flat. Computation of the effects of Pinatubo for example are very crude. The aerosols affected weather differently as they spread, not just an oversimplified reduction in solar radiation as is performed in the model. The weather response to Pinatubo also included the fact that we were in El Nino beforehand, also poorly modeled in the GCM. Once the GCM's can replicate (not predict obviously since that requires unknowable initial conditions) the frequency and magnitude of climate features like El Nino, then they will be believable for modeling the response to Pinatubo. BTW, proving that humidity has gone up on average means nothing. The distribution of water vapor is the only thing that causes or doesn't cause global warming. If water vapor is evenly distributed then there is global warming, if not, global cooling. There is a large natural range encompassing both cases and a lot in the middle.

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