Saturday, October 1, 2011

Global Warming Litmus Test

     Recently, over at The Atheist Conservative, the conversation turned to global warming. I have frankly avoided writing on climate change. This has not been from delicacy about controversy, as regular readers know. It has been instead from simple doubt. There seemed to be clarity on global warming some years ago. The basic effect of greenhouse gasses is indisputable, and carbon dioxide is demonstrably the culprit for why Venus is hotter than Mercury even though it is twice as far from the Sun. Human civilization clearly produces a lot of carbon dioxide, and there certainly seems to be an impressive correlation between recent (100 years or so) rises in carbon dioxide and average global temperature. I am not a climate scientist and do not pretend to be able to sort out what is going on with the weather. As in many other areas (medicine, astrophysics, plate tectonics), I was initially prepared to trust the experts. But...



     It began to be apparent a few years ago that some climate scientists were doctoring their data. This is the cardinal sin of science. Granted, they might be right nonetheless, but perhaps they were overstating things a little. Or a lot. Perhaps the warming is not going to be as bad as they fear. A second look at (for instance) some of the data Al Gore cites shows a drop of half a degree during the first century of industrialization [An Inconvenient Truth, p. 65]. This result is counterintuitive (at least).

     Unlike some religious conservatives, for whom non-human species are sometimes just a God-given resource, I dearly regret every extinction. In the whole of the universe, we know of no place besides Earth where life definitely exists. Each Earthly species is therefore profoundly unique. Indifferent nature has been driving species extinct without our help for æons, but we might think of ourselves as a little less indifferent than an unknowing cosmos. Still, human lives are ultimately more important (else how could we eat meat, for instance?). The economic activity of an awakening global market is lifting billions of people from poverty. That is a very good development. Endangering it on grounds of discredited science would be unconscionable.

     So, is climate science discredited? A few researchers definitely have been. Perhaps more than a few. My own experience with academics is that as soon as their work approaches anything with political implications, its quality as science diminishes. On the other hand, the basic premise of global warming remains sound. What seem to me in doubt are (1) the degree of warming and (2) the extent to which human economic activity contributes to it.

     What is needed? Clean data, to start with, so that we can be sure of the extent of the problem. With partisans on both sides hurling accusations at each other, it may be impossible to obtain such data for some time. On the other hand, perhaps we already have the facts but simply cannot recognize them as clean because of the mud and vitriol. As an issue, global climate change has become a litmus test for both Right and Left. It is astonishing how people proclaim their certainty when the complexity of climate science is beyond all but a few specialists—and they seem to be the least certain of all.

     With this much doubt on the topic, it seems unwarranted to impose major economic dislocation on billions of humans when we cannot even agree on whether the data are actionable. In the military, facts are sometimes referred to as actionable intelligence when they provide sufficient clarity and certainty as to an enemy’s intentions or capability. Regarding climate change, we seem to lack actionable intelligence. By contrast, our economic and moral dangers are widely apparent. In the triage of emergent dangers to civilization, we are better advised to spend our efforts on balancing the budget and figuring out what to do about the decline of the family. In any event, if we can accomplish these difficult tasks, we will be in far better shape to handle a rising tide.

9 comments:

  1. Consvltvs, if you read the IPCC report, please also read some of the many criticisms of its findings - easily found on the net. "Watts Up With That" is a good source. So is "Climate Debate Daily" which gives arguments on both sides of the debate.

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  2. "My own experience with academics is that as soon as their work approaches anything with political implications, its quality as science diminishes."

    Very true. I noticed it in my own major in undergrad (linguistics), where phonetics, phonology, and morpho-syntax had more genuine debate and more rigorous standards than the courses on language and culture or language and gender. When it comes to topics with big political impact, such as climate science, the science becomes even less useful.

    It doesn't help that some scientists have trouble separating their activism from their study.

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  3. A simple equation based on the physical phenomena involved, with inputs of only sunspot number and ppmv CO2, calculates the average global temperatures (agt) since 1895 with 88.4% accuracy (87.9% if CO2 is assumed to have no influence). The equation, links to the source data, an eye-opening graph of the results and how they are derived are in the pdfs at http://climaterealists.com/index.php?tid=145&linkbox=true (see especially the pdfs made public on 4/10/10, 3/10/11 and 9/22/11).

    The future average global temperature trend that this equation calculates is down. The huge effective thermal capacitance of the oceans (about 100 times everything else) will cause the decline to be only about 0.13°C per decade. The decline may be as much as 0.22°C per decade if the sun goes really quiet.

    This trend is corroborated by the growing separation between the rising CO2 and not-rising agt. From 2001 through August, 2011 the atmospheric CO2 increased by 23.1% of the total increase from 1800 to 2001 while the average global temperature has not increased. The 23.1% CO2 increase is the significant measurement, not the comparatively brief time period.

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  4. Jillian: I've checked out both sites. Thanks as always.

    Hortensio: I was thinking about gender studies, so you read my mind. I suppose we should forgive academics for being human. Thomas Sowell's excellent book Intellectuals and Society provides useful insight into why they are so often biased in the direction they are.

    Dan Pangburn: This is exactly what I want, data and logical analysis. Thank you. There is a saying in my line of work, referring to how any given case is likely to resolve: Change the facts and you will change the outcome.

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  5. Thanks for the feedback.

    I too am a Thomas Sowell fan. I recently read another of his excellent books titled Basic Economics.

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  6. From Harold Vandenburg, via e-mail:
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    Dan: I am trying to understand your equation - I would be grateful for clarifiaction.

    The first term in brackets - is this the total number of sunspots since start time? This is a proxy for solar activity and therefore the total energy input?

    From this we subtract the global temperature ^4, times 6.52 x 10^-9. Is this the total radiation from Earth, and hence the total energy output?

    From this we subtract "a"

    We then add ESST. Can you explain ESST? Most google hits are from your own posts, where you replace SST with ESST. Can you please explain this, as I am not clear what it is.

    We then add the log term for the ratio of CO2/ start concentration CO2.

    In the absence of any other terms, the input / output term would "predict" a direct link betweem anomaly and sunspots. Actual plots of this kind show a reasonable correlation until recent decades, when the temperature rises even as the incident radiation falls. This is usually "explained" by the increase in forcing by CO2. In your equation, this is mainly "explained" by the ESST.

    The key to introducing the periodicity is the ESST, which is adding and subtracting large amounts of energy. Can you please explain this?

    I also notice that tthe fit is not very good for the early years of the plot. Your ESST term seems to be adding a periodicity not shown in the data at that end. Is there any data going back further?

    I do not see why anyone would find this more convincing than the huge body of peer reviewed published data. If Dan gets back with some clarifications, we can discuss further.

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  7. The general methodology is fairly well described in the 4/10/10 pdf but perhaps the following will help.

    “…is this the total number of sunspots since start time?” It is, but, since time increments are all equal (1 year), it is also the time-integral of sunspot numbers. Thus it takes both magnitude and duration into account and becomes a proxy for ‘energy in’. Others just took either peek magnitude or spacing of cycles into account.

    “…total radiation from Earth…” Yes, it’s ‘energy out’. Page 6 of the 3/10/11 pdf explains about 6.52E-9.
    Energy in minus energy out = change in energy stored. You may recognize this as the first law of thermodynamics. Dividing ‘change in energy stored’ by the effective thermal capacitance results in the contribution of this factor to temperature anomaly.

    Note that ‘a’ is just an offset, much like the derived constant (the one that is not multiplied by the independent variable) in a linear regression. All that it does is move the curve to, on average, overlay the data. It shifts the curve without changing its shape.

    ESST is short for Effective Sea Surface Temperature. If such a thing could be measured it would be the average surface temperature of all of the oceans in isolation from external influence (thus constant total energy) but with currents and internal non homogeneity of temperature. The general character, 32-year long up trends and down trends and approximate magnitude were arrived at by observation of average global temperature history directly measured since about 1880 with some consideration of PDO data. The result is a saw tooth shape with the last low point in 1973 and last high point in 2005. The magnitude for best fit to measured temperatures is always about +/- 1/6°C. The fact that it results in high coefficient of determination for over a century indicates that it should hold fairly well for a couple more decades.

    “…add the log term…” Early versions of the equation assumed a linear influence of CO2. Since the range is fairly small, changing to the more correct logarithmic decline of influence made a minor improvement.

    “Actual plots of this kind show a reasonable correlation until recent decades, when the temperature rises even as the incident radiation falls. This is usually "explained" by the increase in forcing by CO2. In your equation, this is mainly "explained" by the ESST.” This is the crux of difficulty in understanding the equation. The ‘Actual plots’ that you refer to are Total Solar Irradiation (TSI) which changes very little. What I calculate is energy retained by the planet which is entirely different and continues to correlate.

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  8. continued,

    A graph which shows the upsurge in the sunspot time-integral that started in about 1941 is on page 14 of the pdf made public 4/10/10. I describe the mechanism by which I think the increase in retained energy happens in the pdf made public 6/21/11. Another theory is that sunspots influence the latitude of the jet stream. I have no insight on this.

    The agt increase (which ended about a decade ago as indicated by measurements but about 6 years ago as calculated by the equation) is explained by the time-integral of sunspot numbers. ESST is a ‘background’ oscillation with no net change over its 64 year period. The decline from 1941 to 1973 would have been about 65.6% greater if not for the net energy gain from the sunspot time integral. The rise from 1973 to 2005 combined the rise of the cyclic ESST with the net energy gain from the sunspot time integral. The result was an increase about 81.6% greater than it would have been without the increased sunspot time-integral. (These values supersede the values in the 4/10/10 pdf. The values if CO2 is assumed to have no influence are 66.5% for 1941 to 1973 and 60.2% for 1973 to 2005)

    “…ESST, which is adding and subtracting large amounts of energy.” ESST does not add or subtract energy. (See above) It only indicates change in average surface temperature as a result of upwelling and down-welling. This is discussed further on pp 3-4 in the 9/24/11 pdf.

    “…fit is not very good for the early years.” I have not looked at earlier times or tried to reconcile the poor match prior to 1895 mostly because of increased uncertainty in the accuracy of the older temperature measurements.

    “I do not see why anyone would find this more convincing than the huge body of peer reviewed published data.” There are many egregious mistakes in the ‘peer reviewed published data’. I describe some of them in the pdf made public 8/11/10.

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  9. continued further,

    The usual journals are hopelessly biased. The reviewers that they usually assign to climate related papers are meteorology types who are not knowledgeable in a lot of relevant science and are unaware of it. Some of the disciplines that they may be deficient in include computer modeling, mathematics, heat transfer, thermodynamics and feedback theory, all of which are familiar to an experienced Mechanical Engineer like me.

    Consider also this quote in http://www.mja.com.au/public/issues/172_04_210200/horton/horton.html by Richard Horten, editor of the Lancet “But we know that the system of peer review is biased, unjust, unaccountable, incomplete, easily fixed, often insulting, usually ignorant, occasionally foolish, and frequently wrong.”

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