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Comments 110551 to 110600:

  1. 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.
  2. 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.
  3. 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.
  4. 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 :-)
  5. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    Excellent rephrasing, MrJon!
  6. 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.
  7. 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!
  8. 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.
  9. 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.
  10. 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.
  11. 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.
  12. 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.
  13. 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!'
  14. 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? :-)
  15. 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.
  16. 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.
  17. 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.
  18. 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)
  19. 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 ?
  20. 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
  21. 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.
  22. 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!
  23. 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!'
  24. 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.
  25. 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.
  26. 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.
  27. 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).
  28. 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 :-)
  29. 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?
  30. How we know the sun isn't causing global warming
    Ned @ 11 Fair point :-)
  31. 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...
  32. 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.
  33. Berényi Péter at 19:49 PM on 9 September 2010
    Climate and chaos
    #24 Ned at 00:53 AM on 9 September, 2010 Its behavior can be ascribed to obvious physical processes I wonder if anyone were capable to implement a computational birdie model based on those obvious physical processes that could predict the trajectory of birdies dropped. Or even say anything meaningful on the statistical population of such trajectories.
  34. The surprising result when you compare bad weather stations to good stations
    chriscanaris, keep in mind that you're looking at the result of averaging large numbers of stations. Intuitively, one might guess that individual poorly sited stations would have larger variance in their trends (some with too much warming due to new pavement nearby, others with too much cooling due to the growth of trees, and of course many others might be poorly sited but nonetheless have no particular bias to their trends in either direction). To some extent, all of this will cancel out in the process of aggregating to the nationwide scale. In any case, I find this juxtaposition (from your comment) a bit odd: Scientists have nothing to lose if they present real data limiting adjustments only to what needs adjusting to ensure we're comparing apples with apples. I would feel far more comfortable with data showing wider divergence between well and poorly sited stations. Well, the Menne paper does just present real data comparing apples to apples. They just divided the set of stations into two groups, those classified as well-sited and those classified as poorly-sited, and then compared the average trends for both groups. There were no differences in how the two groups were handled or "adjusted". But it sounds like you still have some predetermined outcome that you want to see. Unless there's a divergence between the two mean trends, you won't feel comfortable. This does sound like a "lose-lose" proposition for Menne.
  35. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    Well, that's quite enough obfuscation for one thread. Let's get back to basics here and recall what all this was about - prior to attempts to change the subject. This is what Dr. Pielke Sr claimed: “Global warming, as diagnosed by upper ocean heat content has not been occurring since 2004”. I made the following observations: • one metric alone (ocean heat, however measured) cannot be indicative of the state of an entire climate system. • significance attributed to a four year period is specious because it’s too short a period from which to draw any kind of conclusion, especially when there is considerable uncertainty within the scientific community about the validity of the data, the methods of gathering it, and the analysis applied to it. • 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. While I appreciate Dr. Pielke engaging with us, I find there has been a concerted effort to change the subject, to deflect criticism, and a failure to answer what I believe are robust and clearly stated criticisms. Sophistry will not change my view, nor will hyperbole or obfuscation. My criticisms therefore stand as written, and I reject the rather circuitous attempts to defend statements that owe more to climate change skepticism than they do scientific research. I believe that clear bias is displayed in such incautious statements, and - most importantly - they present opportunities for less principled actors to distort, delay and pervert government, civil, media and legislative measures to address what is potentially the most serious problem mankind has ever faced. Dr. Pielke - I find you are handing live ammunition to the enemies of science e.g.the ones calling for climate change advocates to be flogged and books to be burned. Please be more circumspect about the inevitable politicisation of what you say. It's not what you say, it's the way you say it, right?
  36. A detailed look at climate sensitivity
    Hi, cruzn246. I agree that it was probably warmer than today at the peak of the previous interglacial; my point was just that we don't necessarily know exactly how much warmer because Antarctic ice cores aren't necessarily giving us the global mean temperature -- temperatures in the Southern Ocean are probably weighed more heavily. As for the distribution of plant communities, the biosphere had thousands of years to adjust to warming temperatures at the time. Right now we're raising CO2 and temperatures on a decadal-to-century time scale. It takes a while for things to come into equilibrium (which won't actually happen until after we stop increasing CO2 concentration).
  37. How we know the sun isn't causing global warming
    I shall read with keen interest the links put in the response to #6. In the meanwhile, my original point has now been reinforced. This blog entry's text needs to be edited and the more up-to-date works added to it.
    Response: We have 3 different rebuttals to the "It's the sun" argument. This blog post is the Advanced version. All the papers posted in that earlier response come from the Intermediate version which features a fairly extensive list of peer-reviewed papers on the solar influence on climate. The Basic version hits the subject in a very brief, simple manner. Something for everyone.
  38. The surprising result when you compare bad weather stations to good stations
    chriscanaris @63: "What puzzles me..." Indeed..it puzzles you, me, Menne, Jim Meador and (I suspect) also John Cook and a great number of people. Alas, not everybody is as interested in the science.
  39. How we know the sun isn't causing global warming
    Argus, you're right that spectral reflectance varies as a function of incidence angle. In the analysis presented in this thread, the author simplifies this with the assumption of an overall average albedo of 0.3, or an absorptance of 0.7 (that's where the "0.7" comes from in the equation dF = 0.7 * d(TSI)/4 way up at the top). That's probably good enough for a nonspatial model like this. If you want to look at the energy balance of a particular point on the Earth's surface over time, then you're absolutely correct -- you might have to take into account variance in reflectance as a function of solar elevation angle.
  40. How we know the sun isn't causing global warming
    Hi, chriscanaris. Erlykin 2009 find that solar irradiance (and cosmic ray flux, for that matter) could explain at most 14% of the warming since 1956. It's an upper bound, not a best estimate. They don't attempt to come up with an actual estimate of the magnitude of warming attributable to TSI or CRF, just that for the period 1956-present it has to be less than 14% of the observed warming. You also want to keep in mind the difference in time periods. As noted above, some of the papers do find non-negligible values for the influence of solar irradiance on temperatures prior to the 1970s. But they pretty much all are in agreement that it's essentially zero since then.
  41. How we know the sun isn't causing global warming
    Thank you Ned, for a quick and clear answer! My thoughts concern the fact that most of earth's surface is ocean, and that a water surface has a varying reflectance (or reflectivity), which is depending on the angle of incidence. For an angle of 60 degrees the reflectivity is still less than 0.1, but for 80 it's almost 0.4 (then rising up towards 1.0). This means that not all of the incoming light (and infrared, etc?) is absorbed, which is what 'divided by 4' is presupposing. Actually a reflectivity of 0.0 is assumed for all angles of incidence. Maybe the constant should be around 4.5 instead? Or even 5?
  42. How we know the sun isn't causing global warming
    ◦Erlykin 2009: 14% ◦Lockwood 2008: -1.3% +/- -0.7 to -1.9% That's a a huge spread of variability if you stop to think about it. Do we understand insolation quite as well as we think we do? 14% -> less than zero in a system acknowledged to have multiple sensitive feedbacks is an awful lot of variability with major implications for climate models and mitigation strategies.
  43. How we know the sun isn't causing global warming
    Argus, TSI is measured in a plane perpendicular to the earth-sun axis. In this plane, the area of illumination is a circle with area (pi r^2). However, when incident on the earth it is distributed over the spherical surface area of the earth, with area (4 pi r^2).
  44. How we know the sun isn't causing global warming
    What exactly is meant by the following: "... divided by 4 to account for spherical geometry" (in the second paragraph)? Can somebody explain this to me? I have higher education in math and physics, so I should be able to understand an explanation - it's just that I need a clue to where the 'universal constant of 4' comes from.
  45. How we know the sun isn't causing global warming
    Not sure what the replies above are about. For example, Raypierre's non-peer-reviewed comments surely can't be put on the same level as peer-reviewed work? Let's go back to my points. The omission of Haigh's 2007 paper is even more glaring given that the first section of the blog mentions works of 2002, 2004 and 2005, plus AR4. Here's some other work of hers around that timeframe, again not referred to by the blog entry above: Gray, L.J., J.D. Haigh, and R.G. Harrison, 2005: Review of the Influences of Solar Changes on the Earth’s Climate. Hadley Centre Technical Note No. 62, Met Office Haigh, J.D., 2003: The effects of solar variability on the Earth’s climate. Phil. Trans. R. Soc. London Ser. A, 361, 95–111. Furthermore, Haigh (2007)'s conclusions are pretty clear. And she already deals with the objection "there is NO trend over the last 30 years in any of the known solar factors that might influence climate" by writing in her abstract: "it is difficult to explain how the apparent response to the Sun, seen in many climate records, can be brought about by these rather small changes in radiation" Here's also some quotes from AR4-WG1-Chapter2: "empirical results since the TAR have strengthened the evidence for solar forcing of climate change by identifying detectable tropospheric changes associated with solar variability, including during the solar cycle" "It is now well established from both empirical and model studies that solar cycle changes in UV radiation alter middle atmospheric ozone concentrations...solar forcing appears to induce a significant lower stratospheric response (Hood, 2003), which may have a dynamical origin caused by changes in temperature affecting planetary wave propagation, but it is not currently reproduced by models" ===== So in 2007 there was some work to do...this is what science at the time said, and this is exactly what the IPCC reported. Does anybody know of any peer-reviewed work on the overall topic of the sun's influence on global warming, updating AR4 and Haigh (2007), either confirming or refuting her statements? ======== Say, can't we even agree on taking AR4 as reference? The impression is that we're back in "more royalist than the king" territory...published science is telling us "we don't know enough", yet the blog post boldly states "we know it isn't the sun". Hardly what is expected from a website where science should be in command.
    Response: Some peer-reviewed research since the IPCC 2007 report:
    • Erlykin 2009: "We deduce that the maximum recent increase in the mean surface temperature of the Earth which can be ascribed to solar activity is 14% of the observed global warming."
    • Benestad 2009: "Our analysis shows that the most likely contribution from solar forcing a global warming is 7 ± 1% for the 20th century and is negligible for warming since 1980."
    • Lockwood 2008: "It is shown that the contribution of solar variability to the temperature trend since 1987 is small and downward; the best estimate is -1.3% and the 2? confidence level sets the uncertainty range of -0.7 to -1.9%."
    • Lean 2008: "According to this analysis, solar forcing contributed negligible long-term warming in the past 25 years and 10% of the warming in the past 100 years..."
    • Lockwood 2008: "The conclusions of our previous paper, that solar forcing has declined over the past 20 years while surface air temperatures have continued to rise, are shown to apply for the full range of potential time constants for the climate response to the variations in the solar forcings."
  46. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    Dr Pielke "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." In principle this might be right, but do you really believe the data is accurate enough quarter on quarter to provide a 3 month earth heat balance ? Given the noise in the data this seems so obviously wrong it's positively alarming coming from a reputable scientist. You repeat several times that the spacial coverage is what matters, but the noise in the data from the spacial coverage seems to show that it cannot be relied on at a snapshot level. Please comment
  47. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    73.Albatross I don't really want to reply to these sorts of comments because they really are going nowhere...... but I can't help it. "It is sad for me to see a reputable and respected scientists tarnish his reputation and diverge from acceptable scientific protocol in this manner." Really, enough of the morality tales! Stick to the science.
  48. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    72.Albatross You seem to make the point I highlight in #71. 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. I think you are taking AchutaRao et al critism of the early poor data set and piling that all on teh ARGO data. I thought Josh Willis on Roger's website did a good job of defending the present ARGO data set and believes there are unlikely to be many large scale corrections. It's funny that you then go on to say how models and data agree over the long term and how you have confidence in the long term trend. "OHC data are sufficiently accurate to state with high confidence (and statistical significance) that the long-term change in OHC is positive" How do you have confidence in a very, very, very poor early data set when you seem to have little to no confidence in the later, global data set. That makes no sense to me. What specifically about the ARGO data don't you like? And what specifically about the early data gives you the confidence in the long term trend?
  49. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    Roger A Pielke Sr #40 "The EOS article is introduced to document that we have identified a wide range of human climate forcings, beyond the radiative forcing of CO2. The IPCC is too conservative at presenting these other forcings. These are in addition to the human caused CO2 forcing." You might want to check the thread at this same website that goes into human waste heat, and I support your concern for possible biologically harmful effects of changes in the atmosphere's composition. That said, I read the article twice, and nowhere found an explanation as to how the additional amounts of anthropogenic CO2 could be warming the ocean to this degree, and how exactly this accomplished, (i.e., direct radiative forcing?, convection? etc.) Normally, oceans are seen to directly influence air temperatures and not the other way around.
  50. Pielke Sr and scientific equivocation: don't beat around the bush, Roger
    HR @68, "Rather than mince words please state clearly exactly what Dr Pielke has said about OHC that is untrue?" Please read the thread. With respect HR, if the answer to that question is not blindingly obvious to you by now you have not being paying close attention. You also say that "Pick apart that reasoning rather than repeatly calling into question his integrity?" Again, you have not being paying attention. For the record, Pielke Snr insisted that people read the EOS article, and that led to the CATO letter. Regardless, Dr. Pielke has only himself to blame for people calling his actions and statements into question. HR, you don't understand, there is no vendetta here, and I am not alone in being frustrated by his cavalier use of words concerning OHC, for example. I own his text book on mesoscale modeling and have cited his work. I respect his work on land-atmosphere interactions, he has clearly made some valuable contributions in that field. BUT, that does not mean I have to agree with him when he elects to publicly make highly misleading statements on climate science, or support him standing idly by when others distort his proclamations even further. It is sad for me to see a reputable and respected scientists tarnish his reputation and diverge from acceptable scientific protocol in this manner. You are of course free to uncritically agree with him on his misleading claims about OHC, sea level and Arctic ice......

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