RCRC Climate Presentation

I made a 30-minute presentation to the California Regional Council of Rural Counties yesterday.   The audience was mainly county supervisors and other officials from about 30 rural counties.  The presentation was the skeptical counterpoint to a presentation by Joe Nation, who among other accomplishments was an author of AB32, the California global warming abatement law.  Download RCRC_Global_Warming_Presentation_update_Sept-25-2008.ppt .  Some of the charts may not be self-explanatory, so I am working on a YouTube video with my speech overlaid on the slides.

It was an interesting experience for me because the audience was hugely sympathetic to my pitch, but frustrated because, for them, it was beside the point:  They were already committed by AB32 to take drastic and expensive action under AB32.  The only policy recommendation I made in my speech was to lament the obsession with cap-and-trade and make a plea for a carbon tax.  The discussion afterward pretty much made my point for me, with every member lamenting the absurdities that are emerging in the CARB regulation process.  Even Mr. Nation admitted that the CARB is setting up programs that are preferentially regulating those with the least political muscle and pushing policies which make no sense in any kind of cost-benefit analysis for fighting CO2.  Mr. Nation said that when he was in the legislature, he tried a carbon tax first but could not get it out of committee, even a small one that would have raised gas taxes about 5 cents.  It seems politicians have no problem enacting huge taxes (which is what AB32 does) as long as those taxes are not called a tax and are hidden from the view of the general public (at least until prices start to rise and businesses start to exit the state).

I thought Mr. Nation did a perfectly reasonable job, and I agreed with much of what he presented.  I differed only, of course, in the amount of past warming I was willing to ascribe to CO2 and the amount of future warming from CO2 that we might expect.  However, this was the first time I have ever seen a global warming catastrophist be explicit that CO2 only causes a bit of future warming, and that most is from positive feedbacks multiplying the greenhouse effect.  Kudos for him for highlighting this, and this certainly fed into my pitch well.

The one area where I thought he made an explicit factual mistake in his presentation was in evaluating Hansen’s forecast to Congress in 1988.  He argued that one shouldn’t judge Hansen by his "A" scenario (which is WAY off) because Hansen said at the time that this was based on unrealistically high assumptions.  But in Hansen’s appendix, he says that the A scenario is based on 1.5% a year future growth in CO2 output.  In fact, the world has grown CO2 output by 1.75 % a year in the last 20 (source), so in fact the A scenario is, if anything, low.  The B and C scenarios should be treated as totally irrelevant.  This is a mistake I think Lucia made at the Blackboard, considering B and C at all.  These scenarios differ in their CO2 forecasts, not the model parameters, so the scenario closest to actual CO2 output should be chosen and the rest are irrelevant.  By the way, here is my chart.  As I did with many of my charts, I like to counterpoint the data against media reports (the box in the upper left).  This helps later in the discussion when the disconnect people have between what I have said and what they have heard inevitably crops up.

Hansen_forecast_1988

I was pleased that Russ Steele of NC Media Watch was there to say hi and observe the proceedings.  Thanks Russ — I enjoy your blog and am sorry that I did not recognize you in my pre-presentation stress. 

Update:  Russ has a more complete roundup of the discussion

Update 2:  The actuals in the chart above are UAH satellite numbers, with the anomaly shifted up about 0.1C to match zero values with the Hansen forecast data.

  • Hi Warren,

    Great presentation, as one Supervisor said, “very dynamic.” Looking forward to your YouTube presentation. I have posted my thoughts and comments on the RCRC meeting on my blog. Thanks for posting a link to your Power Point, you had some great graphics that I want to share with my readers.

    Russ

  • RPJ

    Your comments about Scenario A are misguided at best and dishonest at worst. Scenario A did not assume a 1.5% growth in emissions per year, but a 1.5%/year growth of the annual increment in CO2 concentrations (p9361 of the 1988 paper). The CO2 concentration today, under Scenario A, would be much higher than actually observed.

    Also, it is clearly incorrect to say ‘August 2008 was .3C below June 1988 rather than projected .5C above’, firstly because Scenario A does not resemble the real world, and secondly because no monthly projections were made.

  • An Inquirer

    Few subjects bring out as much passion in blogosphere as Hansen’s 1988 forecasts. Multiple points exist for possible confusion, and I will point out a few. First, there was a paper, and there was testimony to Congress, and they are not identical. Scenario A (1.5% growth) was labeled as the baseline case which most readers would assume is the most likely case unless action is taken. However, Hansen (I think in his testimony) said that he expected Scenario B to be the most likely case because of environmental regulations and resource constraints. Strangely though, Hansen focused on Scenario A in his long term projection. In his famous graphic, he explained that Scenario B assumed no growth in CO2 emissions, but what he meant was that CO2 emissions would grow at a linear rate, not an exponential rate. (For many years, there is not much difference between a linear growth and 1.5% exponential growth.) I find it incredulous that people would believe that as a world we have enacted regulation to limit CO2 — and as been pointed out — emissions have grown faster than the Scenario A assumption. Nevertheless, it matters little even a decade or two later; the difference in emission levels between the two scenarios is small. We have been helped in understanding this last point by Gavin Schmidt who years later revealed the input assumptions. I believe the best analysis of Hansen’s forecasts has been done by Steve McIntyre, and I have posted his analysis before. McIntyre points out that the key driver in the different forecasts for many years is not CO2 but rather other greenhouse gases — some of which were inputed by Hansen in creative ways. (Thanks to Schmidt’s data, McIntrye was able to analyze the role of other GHGs.) Although the Montreal Protocol occurred before Hansen’s forecast, the two occurred close enough together that it is reasonable to place pre-Montreal Protocol GHG patterns in the business-as-usual Scenario A. Therefore, since certain GHGs have been curtailed due to Montreal, it is not outrageous to maintain that overall emissions have tracked Scenario B more than Scenario A. Of course, I understand that Hansen’s model is not reproducible — and therefore not verifiable — for actual experiences of emissions, and that limitation just adds fuel to the passion of discussing this subject.
    An interesting point: Dr. Walt Meier of the NSDIC recently stated that Hansen’s old forecasts are no longer relevant because models have improved vastly in the last couple of decades. He referred to Hansen’s 1980 model — I do not know whether that was a typo for 1988 — or if there are other explanation why he said 1980.

  • “Scenario A did not assume a 1.5% growth in emissions per year, but a 1.5%/year growth of the annual increment in CO2 concentrations (p9361 of the 1988 paper).”

    And the two are different how?

    1.5% growth in emissions
    1.5% growth in concentrations

    Assuming causality between change in emissions and concentrations (and you’ll need be, I think, very careful arguing for any independence between these), the two are identical.

    You seem to be trying to say that 44/88ths is ‘more’ than 4/8ths.

    Perhaps you could explain what the difference is between the proportional growth rate of emissions and the proportional growth rate of concentrations, and how these might vary independently….which is, actually, the import of the distinction you are making.

    If CO2 concentrations aren’t related to emissions, then other factors must be causing any change in Co2 concentrations. What are these factors? Or are you actually trying to say that all the focus on Co2 emissions is just ‘barking up the wrong tree’, so to speak?

  • RPJ

    An Inquirer: I wonder if you’ve actually read either the testimony or the paper from 1988. Your descriptions of them certainly don’t remotely correspond to their contents. Scenario A was not labelled the ‘baseline case’. Scenario B did not assume any environmental regulation or resource constraints: that was Scenario C. Scenario B was clearly described as the most plausible of the three scenarios. There was no ‘focus on Scenario A’. Emissions have not grown faster than the Scenario A assumption.

    Remember that the testimony was written for politicians. Politicians are generally neither numerate or scientifically literate. Science has to be seriously simplified if politicians are to have a hope of understanding it. Therefore, if you think you have found discrepancies between the paper and the testimony, bear this in mind, and always, always trust what is in the peer-reviewed journal paper over what is in the testimony.

    SRasUsual: you’re not reading carefully enough. A 1.5% growth in concentrations is very different to a 1.5%/year growth of the annual increment in concentrations.

  • braddles

    My take on this, from McIntyre’s analysis, is that Hansen actually used a fairly low sensitivity of temperature to increasing CO2. Much of the warming in Scenario A was actually due to wild projections of CFC emissions, which were assumed to continue soaring (in fact they have dropped massively). Whether or not Hansen regarded it as business as usual, it cannot be viewed today as realistic.

    The low sensitivity to CO2 is quite interesting though. This was before they had developed all those positive feedbacks, and their seems to be no emphasis on, or even reference to, ‘tipping points’. The warming is roughly linear and graphs stop after 30 years and only one degree of warming, (admirable self-restraint!); nowadays of course, the modellers have no hesitation to project warming 50 and 100 years out, or even several centuries (in the case of the Stern report).

  • Carl Brannen

    From reading the graph, it appears to me that the “0.5 C above” and “0.3 C below” needs to be changed to “1.0 C above” and “0.6 C below”.

  • J Horvath

    Why have scenarios B and C been removed from the graph? This is disingenuous. Also, The August 08 vs June 1998 is disgusting. Not only have you not compared a like to like, say June with June or August with August, you have totally failed to mention that 98 was a very strong El Nino year, pushing temps far above what they should be, GW or no GW – this is cherry picking of the highest order.

    Argue your case by all means, but spin and lies are pointless. You get caught out and undermine any credibility you have/had.

  • J Horvath: “Why have scenarios B and C been removed from the graph?”

    This was explained in the article. If you object to the reasoning why not explain your objection?

    J Horvath: “you have totally failed to mention that 98 was a very strong El Nino year”

    But wouldn’t doing a complicated adjustment for El Nino make Hansen’s prediction look even worse? Sorry, I cannot see the logic behind your objection?

    Braddles: “Much of the warming in Scenario A was actually due to wild projections of CFC emissions, which were assumed to continue soaring (in fact they have dropped massiambigiousvely).”

    Would you have any peer reviewed papers that you could links us to, that I could read up on this? Excuse my scepticism, but empirical evidence counter to the CO2 hypothesis always seems to be met with highly speculative ad hoc technical excuses. If there is a solid science behind the idea that CFC’s were predicted to drive global warming, that would be very interesting to read about. Being a sceptical website, most readers here would not accept such comments at face value; some links to articles that support this claim would be appreciated.

    An Inquirer: “Dr. Walt Meier of the NSDIC recently stated that Hansen’s old forecasts are no longer relevant because models have improved vastly in the last couple of decades.”

    What does ‘improved vastly’ mean precisely? Does this mean that most of the models have had , say, a better track record in predicting the stasis in temperatures over the last decade? I was under the impression that none of the global climate models made that prediction, so how is ‘vastly improved’ defined? Perhaps twice as good? (I.e., up from 5% accurate to 10% accurate? I’m kidding, sorry.)

    An Inquirer: “Of course, I understand that Hansen’s model is not reproducible — and therefore not verifiable…”

    I agree this appears to be the crux of the problem. Hansen makes three different predictions but is so vague about them that his calculations cannot be replicated, so now anyone can come along later and argue that his predictions cannot be criticised because none of his ‘scenarios’ came to pass. The situation is still somewhat ambiguous. More time will be needed to settle this issue definitively.

  • RPJ

    braddles – you are incorrect. The sensitivity to CO2 predicted by the 1988 models was 4.2°C for a doubling of CO2. That is higher than most estimates today, which tend to lie in the range 1.5-4.5°C.

    Will Nitschke – As anyone who’s read the paper would know, Scenario B was described as the most plausible of the three. Real world forcings have been most similar to those assumed in Scenario B. To only display Scenario A is obviously dishonest.

    Does this mean that most of the models have had , say, a better track record in predicting the stasis in temperatures over the last decade? – there has been no ‘stasis’ over the last decade. A decade is too short a period over which to measure the trend in temperatures.

    I was under the impression that none of the global climate models made that prediction – again, anyone who has read the 1988 paper would be able to look at the graphs and see that in every model, even in Scenario A, there are periods of many years in which temperatures do not appear to rise, or even appear to decline.

  • braddles

    Will Nitschke,

    the sources of warming in Scenario A were presented graphically and discussed by McIntyre (24th January 2008) at

    http://www.climateaudit.org/?p=2645

    Look at the graph labelled “Hansen A”. It shows clearly that by 2020 warming due to CFC11, and CFC12, and “Other Trace Gases” would be greater than the contribution of CO2, with this effect amplifying further by 2040.

  • braddles

    RPJ,

    In Hansen’s 1988 paper, Figure 2 clearly states that an increase in CO2 from 315 ppm to 630 ppm would raise temperature by about 1.25 degrees C.

  • RPJ: “As anyone who’s read the paper would know, Scenario B was described as the most plausible of the three. Real world forcings have been most similar to those assumed in Scenario B. To only display Scenario A is obviously dishonest.”

    I think the argument proposed is that Scenario A most closely matches the real world. (That is the debate in this thread, anyway.) Simply stating “no it doesn’t” without citing evidence is of not much value. Can you support your opinion with evidence?

    RPJ: “A decade is too short a period over which to measure the trend in temperatures.”

    AGW theory is primarily based on just over two relatively recent decades of temperature trends. Could you clarify why you believe slightly more than two decades is sufficient but one decade is not? If you argue that 30 years is required, then AGW cannot possibly be proven yet as we have not had a 30 year trend of steadily rising temperatures. More to the point, the IPCC reports indicated that rising CO2 levels would overwhelm natural forcings and that temperature rises would be fairly steady. There must have been some reconsideration of that viewpoint, I suppose.

    RPJ: “Look at the graph labelled “Hansen A”. It shows clearly that by 2020 warming due to CFC11, and CFC12, and “Other Trace Gases” would be greater than the contribution of CO2, with this effect amplifying further by 2040.”

    Please reread my question. Hansen assets many things that apparently lack validation in the literature and he frequently disagrees with IPCC assessments. I was asking about possible to links to technical articles to support the assertions made. An opinion is not by itself authoritative, even if made by someone such as Hansen. Actually, Hansen’s track record is what is being disputed in this article, so using his opinion as proof is a circular argument isn’t it?

  • RPJ

    It clearly states that the 1.25°C is the warming there would be if there were no feedbacks. The feedback factor they derive is 3.4. Multiply 1.25 by 3.4, and there you have the 4.2°C response to a doubling of CO2.

  • An Inquirer

    RPJ,
    Despite your desire to deny certain features of Hansen 1988, your denials do not change reality.
    I have been generous to Hansen – much more that I would have expected from my Ph.D. committee reviewers and excessively more than I would expect in calls for action in the magnitude that Hansen has urged.
    Hansen’s oral testimony called Scenario A the “Business as Usual” scenario.
    And note page 51 of his testimony: Scenario A assumes that CO2 emissions will grow 1.5% per year and that CFC emission will grow 1.5% per year.. . . My guess is that the world is now probably following a course that will take it somewhere between A and B.”

    (By the way, note Hansen’s use of the use of the word “emissions.” His paper and his testimony refer to emissions when discussing growth rates.)

    In the second panel of Figure 3, only Scenario A is taken through to 2050 and in both panels, Scenario A is plotted as a solid line. Some observers of his oral testimony feel that Scenario B received more attention for its impact in Southeast U.S. rather than being the likely forecast.

    As I have warned, because of these issues, it is easy to get the impression that Scenario A is the scenario that Hansen expected without significant action. (This is especially true considering his description of Scenario B which we will get to later.) However, I have emphasized that Scenario A is not Hansen’s expectation despite page 51 and despite his use of the phrase “Business as Usual.”

    As I have stated, Hansen referred to Scenario B is the most plausible. He described emission growth rates falling from historic 4% to 1.5% in Scenario A due to resource limitations and environmental concerns. Even more so for Scenario B! In his defense, RealClimate has this note, “When Hansen said ‘most plausible’ he was factoring in factors such as limitations on fossil fuels and eventual emissions policies, which may certainly be the case over the longer term but have not interrupted BAU [Business As Usual] as yet.”

    A few notes about Scenario B. In his paper and testimony, he referred to Scenario B as having “constant future emissions.” In his caption on Figure 3, he states that “Scenario B has emission rates approximately fixed at current rates.” On page 51, he says that “If populations increase, Scenario B requires emissions per capita to decrease.” It is difficult to guess from these descriptions that Scenario B assumes a linear growth in CO2 emissions. Yet, that is apparently what he means. Therefore, in my posting, I have warned people about what he means for Scenario B because one can certainly get the wrong impression.

    It is noteworthy what has been the actual experience in CO2 emissions. I have not seen data that suggests that Hansen’s optimism for Scenario A has been met – estimate of emission growth rates are still above 1.5%. Nevertheless, emissions are not the same as concentrations and certainly with more vibrant vegetation, concentrations could rise slower than emissions. According to information supplied by Gavin Schmidt, the 2008 levels inputted for Hansen’s model was 387 for Scenario A and 385 for Scenario B. Apparently, actual current concentrations are reported to be between 387 and 388. So we have almost met Hansen’s optimism for Scenario A, but not for Scenario B.

    However, as I emphasized in my posting, it is just as important – and maybe more important – to look at other GHGs besides CO2. With that consideration, it is plausible to believe that input data has followed Scenario B more than Scenario A.

    I will leave comparisons of observed temperatures to Scenario results for another posting.

  • morganovich

    rpj is just “scientist” hiding his identity again.

  • morganovich

    quote directly from hansen:

    “Scenario A assumes that CO2 emissions will grow 1.5% per year and that CFC emission will grow 1.5% per year. Scenario B assumes constant future emissions. If populations increase, Scenario B requires emissions per capita to decrease. Scenario C has drastic cuts in emissions by the year 2000, with CFC emissions eliminated entirely and other trace gas emissions reduced to a level where they just balance their sinks. These scenarios are designed to cover a very broad range of cases. If I were forced to choose one as the most plausible, I would say Scenario B. My guess is that the world is now probably following a course that will take it somewhere between A and B. (p. 51)”

    so he is talking about emissions growth.

  • I was originally scheduled to give this presentation, but I had to cancel due to other committments that needed more of my attention. Thanks very much Warren for coming to the rescue, and from what I’ve heard, it was a good job you did.

  • Ben McGinn

    I thought UAH data only started in 1978, not 1960 as demonstrated in the graph. This suggests the data in the graph is manufactured. Perhaps you would comment on how you constructed the pre-1978 data?

  • An Inquirer

    morganovich:
    That is a reasonable inference. However, he is being much more civil, and third parties might gain some understanding through the exchange. I hope that we all take a extra measure of care to be civil.

  • RPJ

    A scientist hiding their identity, and baffling you all with data and theories? What a dirty trick that would be.

    Will Nitschke – I did give you the evidence that Scenario A was not what the author thought it was, and does not match the real world.

    AGW theory is primarily based on just over two relatively recent decades of temperature trends – no it isn’t. It is based on our understanding of the radiative properties of CO2, and our knowledge that human activities have substantially increased the amount of CO2 in the atmosphere. The two decades you refer to are observations that confirm the predictions of the theory, and they are only the most recent uninterrupted part of a much longer warming trend.

    If you are wondering what is the minimum period over which a climate trend can be calculated, the answer lies in the errors. You cannot calculate a trend if the error on the trend you derive is larger than the trend itself. We have weather here on earth. Some years are warm and others are cold, even in the absence of any external effect. To discern the influence of an external effect, you need to observe the system for a period long enough that the trend is evident over the noise.

    More to the point, the IPCC reports indicated that rising CO2 levels would overwhelm natural forcings and that temperature rises would be fairly steady. There must have been some reconsideration of that viewpoint, I suppose. – that is not true at all. Rising CO2 levels do not cause the weather to stop. See what I wrote above.

    An Inquirer – there is no page 51 in Hansen’s 1988 testimony, as far as I can see, so I’m not sure what you’re quoting. In any case, you really need to bear in mind that the testimony was written for politicians, and is obviously highly simplified. The peer-reviewed journal paper should always be referred to in preference to the testimony.

  • An Inquirer

    First, it noteworthy that the latest increase in CO2 emissions has been reported at about 3%! So we have not come down to even Scenario A yet in CO2 emissions. (However, as I have stated before, no one should focus only on CO2; there are other GHGs that influence Scenario A results.)
    And a time for chuckle: it turns out that RPJ (among other pseudonyms) is the one who has not read Hansen’s testimony! — he doesn’t even have the readily available document with page 51! (It is already obvious that he does not have a good handle on the paper.)

  • RPJ

    As I said before, Scenario A did not assume a 1.5% increase in annual emissions. It assumed a 1.5% increase in the annual increment of CO2 concentrations. I think we can all chuckle at someone who can’t even accurately report what another document says. And you think I don’t have “a good handle on the paper”!

    And how about, instead of being immature and claiming that I haven’t read something, you tell me where, in Hansen’s 1988 testimony, I should find page 51.

    And what’s with the accusation of “other pseudonyms”? I find that exceptionally rude, especially when you are hiding behind a pseudonym.

  • Keith

    Sorry, RPJ, but your link did not work. What’s the URL exactly that you are referencing? I’m assuming it is this. One would think that there would be other online copies of this, but I cannot find any. Perhaps Inquirer is referencing a hard copy version that he has access to, perhaps the Congressional Register, that would certainly include details of this testimony. It might have differing page numbers.

  • RPJ

    Thanks, Keith – that is the link I tried to make. Missed off the ‘http://’, so it turned into a relative link instead of absolute.

    I wait with interest to find out from ‘An Inquirer’ where we can find the mysterious page 51.

  • Keith

    You’re welcome, RPJ. I think that there may be a page 51, however, but it is not included at that particular site. If you read through the written presentation that Dr. Hansen provided with his verbal testimony, you will find references to a Figure 4 and an Attachment A. The reference is on page 4 of the written presentation, in Section 3. It is on the seventh of the ten pages of the file. The last page in the Guardian image file is Figure 3, and that is on page 48, and there are no attachments. It is entirely possible that additional figures and attachments would take up three pages.

    Also, the description under Figure 3 on page 10 (or 48 depending upon the numbering you wish to use) says that Scenario A is based upon the assumption that trace gas emissions would continue along the growth rate of the last twenty years, that is 1.5% per year emission growth. As Warren and others state, emission growth has been above the 1.5% rate of this assumption. That would to me indicate that comparing temperature projections from Scenario A to the actual temperature record for the twenty year period from 1988 to 2008 is the most valid comparison. Even assuming Scenario B, the current temperature plot is significantly under its projections. The only plot that comes close to actual temperature records is Scenario C, which assumed draconian reductions in GHG emissions, a scenario that has not occurred.

  • RPJ: “…they are only the most recent uninterrupted part of a much longer warming trend.”

    Sorry I couldn’t really comment on your reply here because it seemed more like a rambling generalisation than anything to do with the discussion on this thread.

    RPJ: “that is not true at all. Rising CO2 levels do not cause the weather to stop. See what I wrote above.”

    Take a look at ar4_syr_spm.pdf easily downloadable from the IPCC website. In particular, “Global and continental temperature change” graph. Compare pink trends (natural and anthropogenic forcings) to blue trend lines (only natural forcings). Anthropogenic forcings completely dominate the projections. Natural forcings are presented as insignificant in comparison. I think the impression this leaves any reasonable person is that for temperatures to flat line or trend downwards over so many years would suggest natural forcings must be counter-acting the anthropgenic forcings (volcanic eruptions?) or at least even allowing for the error range, IPCC projections are not probably disproven, but are presently at the very edge of plausibility right now. So the next couple of years should be interesting to observe.

  • RPJ

    Keith – I would always believe Hansen et al. 1988 (the peer-reviewed paper) over what is said in the congressional testimony. As I’ve said, the latter was obviously highly simplified, being written for non-scientists. The assumption for Scenario A was that the annual increment in atmospheric CO2 concentrations would rise by 1.5%/year, not that emissions would grow at 1.5% per year. In any case, what is more important than the assumptions is how they translated into forcings. The Scenario A assumptions led to forcings much higher than what has actually been observed. This graph shows that Scenario B is obviously the closest to observed forcings.

    Will Nitschke – I think it’s quite clear how what I said about trends related to the discussion, so presumably you just wanted to make a childish debating point and so pretended not to understand. You also have not grasped that weather is what is called unforced variation. If you thought that rising CO2 would eventually stop interannual variation in temperatures, then you’ve catastrophically misunderstood the theory. Fundamentally, a decade is, and always will be, too short a period over which to measure a climate trend of less than 0.5°C per decade.

  • Andy

    Who cares which scenario is which.

    He’s wrong.

  • RPJ

    Please describe what makes you believe that, Andy. I’m sure you’ll agree that simply stating ‘He’s wrong’ offers nothing to the debate.

  • JoeH

    RPJ – ref your 9/29 4:23AM post.

    I visited the NASA/GISS web site here http://pubs.giss.nasa.gov/docs/1988/1988_Hansen_etal.pdf and would like to quote directly from Hansen (1988) section 4.1 Trace Gases:

    “We define three trace gas scenarios to provide an indication of how the predicted climate trend depends upon trace gas growth rates. Scenario A assumes that growth rate of trace gas emissions typical of the 1970s and 1980s will continue indefinitely; the assumed annual growth averages about 1.5% of current emissions, so the net green house forcing increases exponentially. Scenario B has a decreasing trace gas growth rates, such hat the annual increase of the greenhouse climate forcing remains approximately constant at the present level.”

    In your reply to Keith you saY, “The assumption for Scenario A was that the annual increment in atmospheric CO2 concentrations would rise by 1.5%/year, not that emissions would grow at 1.5% per year.”

    How does this square with Hansen (1988) that I read and quoted above? Can you point us to a link that supports your belief that Hansen is referring to concentrations and not emissions? Am I reading it incorrectly?

    Thanks.

  • RPJ: “presumably you just wanted to make a childish debating point and so pretended not to understand.”

    I’m not sure how name calling and insults helps your argument. I think it was fair for me to dismiss your argument that all warming is evidence of anthropomorphic warming — that’s plain silly, and at best an oratorical device meant to mislead.

    RPJ: “Fundamentally, a decade is, and always will be, too short a period over which to measure a climate trend of less than 0.5°C per decade.”

    I never said a decade was long enough to measure a small temperature trend. I just made a couple of observations with regard to that statement. I pointed out that two decades of recent warming was also probably too short to ‘prove’ anthropomorphic warming, and your strange reply implied that all warming was evidence for anthropomorphic warming. My other point was that the IPCC has characterised the anthropomorphic warming signal in either a very misleading way or has to be wrong about the anthropomorphic warming contribution. I would not object to the notion that the IPCC report is perhaps misleading and this may perhaps even be unintentional (just poor graphics)?

    I’m not a member of Greenpeace, I don’t get research grants to do climate science. I don’t work for an oil company. I criticise ‘Deniers’ who write nonsense just as readily as I criticise ‘Alarmists’ who make assertions without supporting links and are then evasive when questioned further.

  • RPJ

    JoeH: I gave the reference earlier, to the same paper you are quoting from. Note that your quote refers to ‘trace gas growth’. CO2 is not the only trace gas, and a few paragraphs below the part you quoted, you’ll find the sentence “The abundances of the trace gases in these three scenarios are specified in detail in Appendix B”. And in appendix B, it is stated that the atmospheric CO2 concentration in Scenario A followed the observed Keeling curve until 1981, thereafter rising with an annual increment increasing by 1.5%/year.

    Forcings in Scenario A were much higher than what has actually been observed, and to display only that scenario alongside phrases like ‘grossly exaggerated’ is grossly dishonest.

  • RPJ

    Will Nitschke: your argument that all warming is evidence of anthropomorphic warming – I never made any such argument.

    As you seem not to have gleaned from my apparently strange reply, your belief that the entire notion that humanity is affecting the climate is based on two decades of rising temperatures is false. You seem very keen for everyone to provide links to things, so how about a link to wherever you got this idea from?

    By the way, anthropomorphic = attributing human characteristics to non-human things. Anthropogenic = originating from human activity. Your tone smacks of a desire to condescend, so how about at least getting the basic terms right if that’s what you want to do.

  • Earle Williams

    It is good to see that RPJ has a copy of Hansen’s 1988 paper at hand. In it, on page 9361, is the description of scenario A (hand transcription, I claim all typos):

    Specifically, in scenario A CO2 increases as observed by Keeling for the interval 1958-1981 [Keeling et al, 1982] and subsequently with 1.5% per year growth of the annual increment

    It may be that Dr. Hansen was confused in his congressional testimony and referred to the increase in the annual increment as an increase in annual emissions. Note however that the 1988 paper does not describe scenario A as consisting of 1.5% increase in CO2 concentration.

    Plotting up the CO2 concentrations used in all three scenarios illustrates the deception contained in RPJ’s initial and subsequent comments.

    http://mtaonline.net/~brose98/proj_co2.png

  • RPJ: “As you seem not to have gleaned from my apparently strange reply, your belief that the entire notion that humanity is affecting the climate is based on two decades of rising temperatures is false. You seem very keen for everyone to provide links to things, so how about a link to wherever you got this idea from?”

    You wrote:

    “The two decades you refer to are observations that confirm the predictions of the theory, and they are only the most recent uninterrupted part of a much longer warming trend.”

    I would just like you to establish firmly how two decades “confirm the predictions” but one decade is “random weather noise…” ?

    I’ve always been confused by that argument. If you said, “well, we need 30 years to establish a trend and we don’t have 30 years of AGW so the theory is not yet confirmed” that would appear reasonable based on your own logic. We’re not dealing with random coin flips here. We’re already dealing with a global average temperature. There should be a significant non-random aspect to it. ‘How much’ is the open question, perhaps.

    “Anthropogenic – Anthropomorphic”

    Yes, you’re right of course.

  • RPJ

    Earle Williams – if you want to retract accusations of ‘deception’, I’ll talk to you. Otherwise, if that’s your standard of debate, I’ll leave you to it.

    Will Nitschke – two decades do not ‘confirm’ the theory. That was a poor choice of words. They provide observational evidence which backs the theory, and in that respect they are just the tip of the iceberg and not the totality of it, as you seem to believe. CO2 driven warming has been going on ever since CO2 concentrations began to rise appreciably above the background level, and not just over the past three decades.

  • JoeH

    RPJ
    I read the portion of Appendix B pointed to in your response to my question. Indeed, Hansen does point to Keeling as the source of data for calculating CO2 increases i.e., concentration levels. Interestingly enough in the next sentence referring to other trace gasses, Hansen refers to “emission rates” as complied by the Chemical Manufacturers Association. And then he switches back to concentrations for CH4. While I can’t get into Hansen’s mind, I have trouble understanding why he would use the term “emissions” in section 4, the body of the paper (and congressional testimony), and then in an appendix describe the basis for his computations to be “concentration levels”. The man after all has written and a number of peer reviewed papers, is educated far, far beyond the levels most of us reach and knows the difference between the two terms. As for his testimony to Congress, while I might be giving them more credit than they deserve, I would posit that even the dimmest bulb in that august body (that would be Senator Boxer) could, with a 30 second explanation, understand the difference between the two terms. So, sorry to repeat the question, why in the body of the paper would he use the term emissions? I guess my take away is that an argument could be made that Hansen is deliberately obfuscating the issue but to what end puzzles me. May be this suggests that the peer review of this paper wasn’t what it should have been since a basic error such as confusing concentrations and emissions should have been caught in the process.

    But back to the source of the comments on Warrens presentation which I believe is on target. If the concentrations levels over the last 20 years increase as Hansen describes “1.5% per year of the annual increment”, at the end of 2007 they would be on the order of 385 ppm. Data from Mauna Loa show that the measured CO2 concentration at the end of 2007 was at 383.7 ppm supporting Warrens conclusion that Hansen is “WAY off”.

  • RPJ: They provide observational evidence which backs the theory

    Warming by itself doesn’t back the theory. The warming is what needs to be explained. It’s not evidence for the theory. This is circular reasoning.

    RPJ: “and in that respect they are just the tip of the iceberg and not the totality of it, as you seem to believe. CO2 driven warming has been going on ever since CO2 concentrations began to rise appreciably above the background level, and not just over the past three decades.”

    Perhaps you could outline (even in bullet form would do) what some of this unseen iceberg consists of that is not largely speculative and has stood up to reasonable scientific scrutiny?

    To equate a warming cycle as evidence for human driven climate change is insufficient as warming cycles occur without human driven components. The question is, what percentage of the recent warming cycle is approximately anthropogenic and how can we distinguish the ‘natural’ from the ‘anthropogenic’ ?

    You make lots of assertions and statements of facts existing, but then seem unable to present any when pressed…?

    BTW, on the evidence I’ve been able to find I do take the view that AGW is real, simply on the basis of first principles, i.e., CO2 should warm the atmosphere based on our knowledge of basic physics. What I’m having trouble determining is how one can spin this into catastophism based on the actual good science available to us.

  • RPJ

    You make lots of assertions and statements of facts existing, but then seem unable to present any when pressed…? – this attitude is offensive. Your tone is not conducive to sensible discussion. Are you seeking sensible discussion?

  • RPJ, no doubt you’re very passionate about what you believe in and you want to save the world and all that, but you do need to back-up your assertions with convincing arguments if you want to be taken seriously on a sceptical website. People don’t have infinite patience.

    I agree with you re: Hansen. His prediction can’t be shown to be ‘wrong’ because it was a ‘scenario’ and not a prediction, and since it’s impossible to know in advance the future mix of trace gases in the atmosphere, anything he claims can never be disproven. But if we grant him that, then it seems to me that if his scenarios are fundamentally unfalsifable he is not doing science. Social and political ‘engineering’ perhaps, but not science. And therefore his ‘scenarios’ should not be given the weight they currently receive.

    I suspect we both have similar concerns regarding the environment and humanity in general. But we have to be guided by the best science we have and not ideology. Should we spend a trillion dollars on carbon sequestration when we could for the same money get unlimited clean power on-line in the form of workable fission reactors? Should we be spending millions of dollars trying to discern the AGW signal from ‘weather noise’ when we spend about zilch on monitoring asteroid collisions? (We’ve already been hit several times this century by asteroids that fortunately did not strike populated areas–had they, hundreds of thousands, if not millions, would have been killed.) We have to separate plausible threats to the environment from those that are, based on our best knowledge, more implausible, even if they have captured the public imagination for a time.

  • ‘Fusion’ not ‘Fission’ before you jump in and correct me. 🙂

  • RPJ

    Your patronising first sentence is yet more evidence that you are not in fact seeking sensible discussion, but just looking to make immature snipes. I must say, with Earle Williams’ accusations of deception, ‘An Inquirer’ accusing me of hiding behind pseudonyms, and your obvious lack of interest in substantial argument, it looks as if intellectual standards on this forum are pretty low.

    If you are unhappy that I have failed to guess what things you wish to see evidence for and what things you already know are true, just make a list of what you want to see. And unless you consider yourself exempt from needing to produce evidence to back claims, then you might want to give some links to back what you’ve said – you have conspicuously failed to offer any evidence whatsoever to support your assertions so far.

  • Earle Williams

    RPJ,

    You are incapable of debate. You assert falsely that Hansen’s Scenario A involved a 1.5% annual increase in concentrations. You have the paper at your disposal. You have the internet at your disposal. Yet you persist in maintaining the charade that Warren’s analysis is flawed because the scenario he describes doesn’t match the scenario fantasy that you attempt to portray it as.

    You are wrong about Scenario A. If you were to apologize to Warren and the readership here then I may be convinced that you are indeed a sincere but incompetent individual trying to have reasoned debate. Absent that I remain convinced that you are a pretender with an agenda using every bit of misinformation and deception at your disposal to stroke your fragile ego and discredit the host of this site at every opportunity.

  • RPJ

    I did not assert that. Do not attempt to slander me if you can’t even understand what I wrote.

  • JoeH

    Earle,

    I’ve read and re-read Hansen’s 1988 paper(source: my post above) and one could certainly make the case that there is some ambighity. As I noted in an earlier post here, he clearly used the term “emmsssion” in the body of the paper. In the appendix which cites his source for CO2 growth he cites Keeling, i.e., CO2 atmospheric concentrations as measured at Manua Loa on the island of Hawaii. Subsequently he used a source that appeared to measure emissions and not concentrations for CH4 as I also previously noted. I am not sure there was an accepted source for CH4 concentrations at that time. Be that as it may, he still in this case used emmissions.

    It would seem to me that if Hansen was using emmissions for CO2 he would have cited the Carbon Dixoide Information Analysis Center (CDIAC) http://cdiac.ornl.gov/by_new/bysubjec.html#trace or the Energy Information Administration (EIA) http://www.eia.doe.gov/pub/international/iealf/tableh1co2.xls. Both of these agencies track global emmissions.

    Like you, I believe that Warrens post is “right on” in that a 1.5% incremental growth in since 1988 would but them within 1 or 2 PPM of currently measured concentrations.

    Hansen muddied the waters by using the term emmissions in both his congressional testimony and the body of Hansen 1988. As for his reasons for doing so, only he can answer that question. I believe RPJ is on firm ground when he asserts that Hansen used concentrations as the basis for his “forecast” of temperatues in response to rising CO2 levels. Notice I skirted the issue by bringing in a third term. 🙂 I also think the point is moot because of reasons previously stated.

    I’m a big guy so if I am incorrect in this analysis please don’t hesitate to point out my errors.

  • Earle Williams

    JoeH,

    The scenario A that Hansen used in his 1988 paper for CO2, methane, etc is available online. The data was provided by Gavin Schmidt outside normal NASA channels, but no one has alleged that it is inaccurate. The increase in CO2 from 1988 to present for all practical purposes is linear, and is virtually indistinguishable from the CO2 projection for scenario B and virtually indistinguishable from the observed CO2 values reported from Mauna Loa.
    Data here
    My graph of the data here

    RPJ’s opening salvo (what RPJ would call reasoned debate, I presume) was this:

    Your comments about Scenario A are misguided at best and dishonest at worst. Scenario A did not assume a 1.5% growth in emissions per year, but a 1.5%/year growth of the annual increment in CO2 concentrations (p9361 of the 1988 paper). The CO2 concentration today, under Scenario A, would be much higher than actually observed.

    This is an unsupported allegation with no explanation as to how the increase would be higher, nor with any link to supporting data or analaysis. One would think a person demanding links from others would be able to supply their own.

    As far as Warren’s post refuting the claim in the press that “global warming is three times fatser than worst predictions”, I believe his graphic does an admirable job demonstrating that the press hype is a bunch of meaningless drivel. Observed CO2 is a darn close match to both scenario A and B, so I have a hard time buying any rhetoric from RPJ, Scientist, or anyone else that CO2 was meant to be unrealistic. The overall forcing from those scenarios though include all greenhouse gasses, including methane, N2O, CFCs and other trace gasses. Steve McIntyre took a look at the forcings derived from each scenario compared to the calculated forcing from greenhouse gasses here. There you will see that up until 1990 or so the observed greenhouse gas forcings exceeded the projections of scenario A. So any statement that in 1988 Hansen thought scenario A was unrealistic is speculation at best, but I would be more inclined to categorize it as unmitigated BS.

    I think it is pointless to wrestle the greased pig of RPJ’s semantic gyrations. Look at the projections and look at the observed greenhouse gass concentrations. Look at the projected forcings and look at the forcings calculated from the observed greenhouse gas concentrations. Then ask yourself who exactly is misguided at best and dishonest at worst.

    Cheers,
    Earle

  • Yes unfortunately I have to agree with that assessment. Lots of loud assertions of misrepresentation, no facts presented, then more evasions when pressed. Now he’s crying that his feelings are hurt…

    But I would caution against extrapolating from the mind set of a person of that particular personality type to that of the actual AGW science. In fairness, sceptical websites tend to accumulate their fair share of ‘crackpots’ to balance out ‘true believers’.

    Very interesting thread. I appreciate everybody who posted good quality information and who made insightful comments. Learnt a few things here this week…

  • Keith

    From RPJ – Keith – I would always believe Hansen et al. 1988 (the peer-reviewed paper) over what is said in the congressional testimony. As I’ve said, the latter was obviously highly simplified, being written for non-scientists.

    From Warren’s blog post – The one area where I thought he made an explicit factual mistake in his presentation was in evaluating Hansen’s forecast to Congress in 1988. He argued that one shouldn’t judge Hansen by his “A” scenario (which is WAY off) because Hansen said at the time that this was based on unrealistically high assumptions. But in Hansen’s appendix, he says that the A scenario is based on 1.5% a year future growth in CO2 output. In fact, the world has grown CO2 output by 1.75 % a year in the last 20 (source), so in fact the A scenario is, if anything, low. The B and C scenarios should be treated as totally irrelevant. This is a mistake I think Lucia made at the Blackboard, considering B and C at all. These scenarios differ in their CO2 forecasts, not the model parameters, so the scenario closest to actual CO2 output should be chosen and the rest are irrelevant.

    Since Warren was comparing to Hansen’s Testimony, not the later paper, I think it is save to say that his comparison is valid based upon the criteria he used. If Hansen made a simpler version for politicians, than it is his own fault for not having a better proof reader or a better knowledge of the English language. Either he meant emission growth when he used the term in the secondary paper which was to be entered into the Congressional Record (making it a Federal Document of Record), or he did not consider the implications of the document and poor choice of wording, and the strength of his case is weakened as he himself did not take it seriously enough to give it his best effort and work. Words mean things, especially when giving evidence before our government, even if things have been carefully stage managed to make your audience more likely to believe you.

  • RPJ

    Keith – the testimony was describing exactly the same work as the paper, only in simplified terms. Perhaps over-simplified, you might argue. But there is no distinction between a comparison to the results presented in the paper, and a comparison with those presented in the testimony. It is dishonest to present only Scenario A, regardless, because the forcings assumed in Scenario A were much higher than what’s subsequently been observed.

    Will Nitschke – like I said, if I failed to correctly guess what you understand, and what you still need to learn, then just put down a list. It’s pathetic to say ‘no facts presented’, really pathetic, especially when you have presented not one shred of evidence to back your own confused ramblings.