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Transparency in climate science

Good thing? Of course.*

I was invited to give a short presentation to a committee at the National Academies last week on issues of reproducibility and replicability in climate science for a report they have been asked to prepare by Congress. My slides give a brief overview of the points I made, but basically the issue is not that there isn’t enough data being made available, but rather there is too much!

A small selection of climate data sources is given on our (cleverly named) “Data Sources” page and these and others are enormously rich repositories of useful stuff that climate scientists and the interested public have been diving into for years. Claims that have persisted for decades that “data” aren’t available are mostly bogus (to save the commenters the trouble of angrily demanding it, here is a link for data from the original hockey stick paper. You’re welcome!).

The issues worth talking about are however a little more subtle. First off, what definitions are being used here. This committee has decided that formally:

  • Reproducibility is the ability to test a result using independent methods and alternate choices in data processing. This is akin to a different laboratory testing an experimental result or a different climate model showing the same phenomena etc.
  • Replicability is the ability to check and rerun the analysis and get the same answer.

[Note that these definitions are sometimes swapped in other discussions.] The two ideas are probably best described as checking the robustness of a result, or rerunning the analysis. Both are useful in different ways. Robustness is key if you want to make a case that any particular result is relevant to the real world (though that is necessary, not sufficient) and if a result is robust, there’s not much to be gained from rerunning the specifics of one person’s/one group’s analysis. For sure, rerunning the analysis is useful for checking the conclusions stemmed from the raw data, and is a great platform for subsequently testing its robustness (by making different choices for input data, analysis methods, etc.) as efficiently as possible.

So what issues are worth talking about? First, the big success in climate science with respect to robustness/reproducibility is the Coupled Model Intercomparison Project – all of the climate models from labs across the world running the same basic experiments with an open data platform that makes it easy to compare and contrast many aspects of the simulations. However, this data set is growing very quickly and the tools to analyse it have not scaled as well. So, while everything is testable in theory, bandwidth and computational restrictions make it difficult to do so in practice. This could be improved with appropriate server-side analytics (which are promised this time around) and the organized archiving of intermediate and derived data. Analysis code sharing in a more organized way would also be useful.

One minor issue is that while climate models are bit-reproducible at the local scale (something essential for testing and debugging), the environments for which that is true are fragile. Compilers, libraries, and operating systems change over time and preclude taking a code from say 2000 and the input files and getting exactly the same results (bit-for-bit) with simulations that are sensitive to initial conditions (like climate models). The emergent properties should be robust, and that is worth testing. There are ways to archive the run environment in digital ‘containers’, so this isn’t necessarily always going to be a problem, but this has not yet become standard practice. Most GCM codes are freely available (for instance, GISS ModelE, and the officially open source DOE E3SM).

There is more to climate science than GCMs of course. There are operational products (like GISTEMP – which is both replicable and reproducible), and paleo-climate records (such as are put together in projects like PAGES2K). Discussions on what the right standards are for those projects are being actively discussed (see this string of comments or the LiPD project for instance).

In all of the real discussions, the issue is not whether to strive for R&R, but how to do it efficiently, usably, and without unfairly burdening data producers. The costs (if any) of making an analysis replicable are borne by the original scientists, while the benefits are shared across the community. Conversely, the costs of reproducing research is borne by the community, while benefits accrue to the original authors (if the research is robust) or to the community (if it isn’t).

One aspect that is perhaps under-appreciated is that if research is done knowing from the start that there will be a code and data archive, it is much easier to build that into your workflow. Creating usable archives as an after thought is much harder. This lesson is one that is also true for specific communities – if we build an expectation for organized community archives and repositories it’s much easier for everyone to do the right thing.

[Update: My fault I expect, but for folks not completely familiar with the history here, this is an old discussion – for instance, “On Replication” from 2009, a suggestion for a online replication journal last year, multiple posts focused on replicating previously published work (e.g.) etc…]

* For the record, this does not imply support for the new EPA proposed rule on ‘transparency’**. This is an appallingly crafted ‘solution’ in search of a problem, promoted by people who really think that that the science of air pollution impacts on health can be disappeared by adding arbitrary hoops for researchers to jump through. They are wrong.

** Obviously this is my personal opinion, not an official statement.

295 Responses to “Transparency in climate science”

  1. 1

    The issue is not whether to strive for R&R, but how to make scientific progress efficiently.

    The main advantage of sharing data and code is that it saves the rest of the scientific community time when building on your work. It is possible when building on someone’s work that you notice that something does not work and you have to go back and reproduce or replicate the results to understand why, but this is very rare in the natural sciences. (In contrast to more empirical fields like social psychology that do not have a firm theoretical foundation.)

    The person most like to build on your work is your future self. With increasingly good tools for Open Science the main beneficiary of good science practices is likely you.

    I am best know for my validation study from 2012 of homogenization algorithms in the project HOME. Several climate “sceptics” have asked me where my data is. When I gave them the URL they were no longer interested.

    As far as I know only one colleague has used the dataset afterwards and also just as one of many validation datasets, so it would not have been missed much. But I did make a new analysis on the data myself this week. Even after 6 years this was easy because everything was well organised to be able to publish the data. I was the main beneficiary.

  2. 2
    Dan DaSilva says:

    Gavin, I am glad you agree with transparency.

    How can this be an issue?
    Why did it take Trump to force this to happen?

    [Response: Huh? This is nothing to do with Trump, and everything to do with increasing community expectations, larger data volumes, journal policies, better and more usable tools being developed etc. See our previous discussions on the topic going back years. – gavin]

  3. 3
    Eli Rabett says:

    You might want to have a word with the


    A cross one perhaps.

    [Response: They are not a serious operation, and the only case where they mention climate is factually wrong in almost every particular. – gavin]

  4. 4
    Dan DaSilva says:

    1 Victor

    Quote: “(In contrast to more empirical fields like social psychology that do not have a firm theoretical foundation.)”

    Where is the “firmness” in climate science? Climate science has huge unknowns and the only way to run test scenarios is with models. Sure it has a firm theoretical foundation at some level, it just no one knows how the pieces interact or which are most important. Where is the “firmness” in water vapor, clouds, aerosols, and ocean heat transfer/storage? We may very well understand more about the social interactions of people than we do about interactions in climate. How do I dare say these things? Scientists have written them.

  5. 5
  6. 6
    Mark Schaffer says:

    Hello Dan,
    What is your provable background in climate research and where have you looked for answers to your questions?
    “WattsUp…” is not a source with any credibility nor integrity.

  7. 7

    Dan DaSilva: “Why did it take Trump to force this to happen?

    It took Trump’s corrupt cronies to convert a scientific movement to adapt to the new possibilities of the internet into a way to protect the political donors from inconvenient science showing that the donors are hurting the health and lives of Americans.

    The abuse of the Trump administration should not be a reason to go back on something that is basically a good idea. If only because the world is a lot bigger than the USA.

    Dan DaSilva: “Where is the “firmness” in climate science? Climate science has huge unknowns and the only way to run test scenarios is with models.

    Your buddies at WUWT & Co. manage to write blog posts about stuff that is physically impossible on a fairly regular basis. Many fundamentalists even deny the existence of the greenhouse effect itself. So clearly physics is helpful in weeding out bad ideas, at least within science.

    If you hold a rock in your hand and you open it, the rock will fall down. If you hold a living organism in your hand and you open it, it may fly away. Nearly any empirical result is possible in the life sciences and you will thus have to put a lot of effort into understanding the processes behind it before you get to firmer physical grounds. That firmer ground includes quantified confidence intervals/uncertainties.

  8. 8

    Eli Rabett: “You might want to have a word with the NAS

    For the innocent: This astroturf NAS, The National Association of Scholars, should not be confused with National Associations of Science, which are legitimate organisations having the interests of science in mind.

  9. 9
    Ray Ladbury says:

    Huge unknowns, huh? Such as? There are error bars on all the critical inputs. And for climate change not to be a serious problem, all those errors have to line up on your side. And based on the data we are seeing, it ain’t lookin’ too good for your side.

    This is why we call you luckwarmers.

  10. 10
    David Young says:

    Seems to me a related issue is whether uncertainty is being biased low by the way the inter comparison project is run. One source of uncertainty is related to parameter choices. If there is no credible observational constraint for the choices, one should I think include a range of runs with a range of credible choices. This looks like a potential form of selection bias that is very common in CFD for example. You run the model varying the parameters until you get a credible result that you like. Then you publish that result sometimes omitting the rest of the results because they “were not the best way to run the code.” The result is that since parameter choices are often not fully specified, replication is difficult and the overall literature is biased in the positive direction. A few papers have appeared recently on this issue. Zhao the al had one on cloud microphysics models I think.

    I don’t know if CMIP5 had such multiple runs of the same model. The number of parameters is in reality quite large ranging from grid density and type to numerical stabilization choices to time steps to turbulence model parameters.

  11. 11
    Hank Roberts says:

    But we’re not about to have another all-DDS-all-the-time thread, are we?
    We’ve been through that before with his cheerfully verbose predecessors.
    Same chant, different speaker.

  12. 12
    bcw says:

    Thanks for the pointer to NAS, digging through their website was fascinating:

    “NAS was founded to confront the rise of campus political correctness.”
    “1992 – NAS proposes and helps establish the American Association for Liberal Education (AALE), an accreditation body focused on liberal education, now located in Washington, D.C.” By liberal they don’t mean “liberal” but the old meaning of teaching philosophy, history, Latin – that kind of stuff – rather than an engineering, science or trade school curricula. The site is a regular potpourri of Alice in Wonderland Humpty-Dumpty word re-purposing.

    Their board is chock full of scientists: political science, linguistics, anthropology. “Prior to working at NAS he was the sole librarian at the John McEnroe Library..” We have “Professor of Philosophy, University of Texas at Austin, where he specializes in the application of logic to metaphysics, the philosophy of mind, political philosophy, and philosophy of religion.” There are no hard scientists on their board or staff.

    If they can do it, so can I; I’ll start calling myself a NOAA scientist (national association of amateur anthropomorphisers …)

  13. 13
    Jacob Coburn says:

    Dan DaSilva,

    Trump had nothing to do with the push for reproducibility in climate or any other science. As Gavin pointed out, it is an age-old conversation that has been going on for years – history didn’t start on January 20, 2017.

    As per your assertions that nothing in climate science is firm, that would require a few things – 1) havign a flagrant diregard for learning and research (all the information you spoke of is out there and available), 2) an unwillingness to confront complex ideas in venues which are not built to simply regurgitate information in a way which conforms with your preconcieved notions and 3) a vast and unsupported assertion that everything you hear (say from climate science) that you don’t like is a lie made up by those outside your “tribe”.

    If you really want to understand climate science and not just have your nonsense reflected on you (which I doubt), the resources are out there (including this site). You just have to actually look and learn.

  14. 14
    ab says:

    About reproducibility and replicability:

    What the greenhouse gas theory does not say, is that when you add more gas into the atmosphere, it scatters more incoming sun rays into the space, and thus it produces less IR rays at ground level.

    This has been reproduced and replicated thousands of time in spectroscopy experiments and even by John Tyndall a long time ago: incoming rays (experimental sun) passing through a tube filled with gas are scattered and at the end of the tube (experimental ground level) less energy is found and proportionally to the addition of gas into the tube.

    This suggests that adding gas into the atmosphere produces less incoming sun rays and less secondary IR ground rays, effectively cooling the climate.

    The atmosphere, made of gases, is indeed a powerful cooling system.

    [Response: A detectable effect for water vapor (in the SW), but not important for CO2. In both cases the effect is overwhelmed by the IR absorption of upwelling longwave. So, not really. – gavin]

    [Further response: Sorry – my comment related to SW absorption, not scattering. See Eli’s comment and link for better info. – gavin]

  15. 15
    Carrie says:

    Sorry, did I say something wrong when submitting this url with comments? or it was only lost.

    about comments at #2 and #13 and so on

    The awareness of issues around reproducing scientific data has been driven by the political nature of climate science, said Andrea Dutton, a geologist at the University of Florida and expert in sea-level rise.

    “Climate science has undergone a lot of public scrutiny as we’re all aware,” she said. “And I think dealing with that has really increased our awareness as a community of being very rigorous about quantifying our uncertainties and being transparent in reporting, being transparent in data archiving.”

    A group of researchers from the academies is reviewing the issue at the behest of Rep. Lamar Smith (R-Texas), chairman of the House Science, Space and Technology Committee. The National Academies will produce a report by the end of the year that explores the issue.

    Smith has accused federal climate scientists of committing fraud and misrepresenting humanity’s role in driving climate change. He was also instrumental in helping shape a new rule proposed by EPA Administrator Scott Pruitt that would require research used by EPA to craft regulations to have data that are public and transparent.

    there seems to be so little shared reality in the human world these days. almost none.

  16. 16
    ab says:

    [Response: A detectable effect for water vapor (in the SW), but not important for CO2. In both cases the effect is overwhelmed by the IR absorption of upwelling longwave.]

    For each molecule of the atmosphere, whatever is its chemical composition (so including CO2 and all GHG or non GHG as well), there is as much probability for a descending SW sun ray than for an upwelling IR ground ray to collide with the molecule, and both rays also have the same probability to be scattered.

    Thus, statistically, by adding more gas into the atmosphere, 1) there is more energy reflected back into the space than energy pushed down onto the ground (because at equal number of SW and IR rays colliding with the molecule, E(SW) > E(IR)), and 2) at incoming SW sun rays constant, there are more SW rays reflected back into the space than before the addition of gases, thus there is less production of secondary IR ground ray.

    Conclusion: by adding gases in the atmosphere, there is less incoming SW energy and less upwelling IR energy, thus a net cooling of the global mean temperature. So the measured global warming in open lands can only be attributed to changes in convection, and thus to global deforestation, and not to any addition of gases within the atmosphere, because all gases have a net cooling effect, independently of their individual propension at absorbing totally or partially some bands of the spectrum.

  17. 17
    Carrie says:

    about uncertainties and unknowns.

    are the impacts from positive feedbacks for a summer ice free arctic circa 2030 or after included in any forecast climate model or the rcp 8.5 scenario (closest trend to current real trend) used in the ipcc ar5 and other papers?

    Given the ar5 said there was no known changes in the AMOC at that time, is any slowing of the AMOC at 15% or more as shown @ included in any published climate models?

    Any examples where they are? Would like to see them. thank you

  18. 18
    Steven Emmerson says:

    ab@14, You’ve got Tyndall’s experiment backwards. The rays entering the tube represent IR radiation from the Earth. The rays exiting the tube represent IR radiation to space. See for more information.

  19. 19
    Carrie says:

    Any well accepted credible climate science papers showing the extent of regional weather and climate impacts from a summer ice free arctic from 2030 or thereafter, say starting a sea ice free period of under 1 month out to 3 months?

    Any well accepted credible climate science papers showing the impacts of arctic sea with only very small areas with MYI no more than 2 years old and with a summer ice free arctic period?

    Any well accepted climate papers or IPCC reports projecting non-summer anomalies consistently above 10C as high as 20C in the high arctic?

    Some refs would be appreciated. It’s a difficult task when over 250 new papers on climate science on average are now being published each week.

    I cannot imagine how the new batch ar6 volunteer reviewers and authors are supposed to effectively and accurately get through the huge numbers of new climate papers since the ar5 at an ever increasing rate to today but with only the same numbers of scientists and ipcc staff and resources of previous assessment reports. The stress levels must be very high while they all try to hold down their day jobs. No one can do teh impossible over an extended period of time. Something has got to give.

  20. 20
    Russell says:


    “For climate change not to be a serious problem, all those errors have to line up on your side. And based on the data we are seeing, it ain’t lookin’ too good for your side. This is why we call you luckwarmers.”

    True believers in the Precautionary Principle who concatenate dozens of worst-case assumptions are equally at risk of  Murphey’s  Second  Law :

                                               If everything must go wrong, don’t bet on it.

  21. 21

    DDS, #4–

    Dan, you are getting carried away. While it is true, of course, that there are substantial uncertainties in understanding and/or modeling “water vapor, clouds, aerosols, and ocean heat transfer/storage”, let’s not forget that all of these are in fact modeled with considerable skill all the time.

    You can’t say the same for basically anything in social psychology, as far as I know. Nor are the underlying mechanisms in social psychology nearly as well-understood as the physical mechanisms involved in climate studies.

    Moreover, there is, contrary to your assertion, considerable understanding of “how the pieces interact [and] which are most important.”

    For example, here’s a search of the water vapor feedback:

    There’s a lifetime of reading right there. But one indicator is to take the top search results ‘as they come’, then compare results filtered by year. Subjectively, it seems to me that more recent papers tend to be much more tightly focused in their scope, which I take to indicate that the ‘big picture’ questions are somewhat settled. (Eg., “The role of the water vapor feedback in the ITCZ response to hemispherically asymmetric forcings,” (2018) as opposed to “Water vapor feedback and global warming” (2000).)

  22. 22
    Hank Roberts says:

    Seriously, guys, read the Eos article, op. cit. above, if you want to follow the scientific conversation.

    If you’d rather keep banging on the political spin, there’s

  23. 23
    Eli Rabett says:

    If you are talking about Rayleigh scattering the scattering is a bit smaller for water vapor than for N2 and O2 (~ 5 x 10^-27 cm2. The CO2, cross-section is maybe 2 times larger. While the scattering is significant throughout the atmosphere, as long as the pressure does not change much there would not be a significant difference. It’s doubtful that such a small scattering would have been seen by Tyndall. Ballpark Rayleigh scattering in his system would be of the order of 1 part in a hundred thousand.

    If you are talking about water aerosols, that would make more sense


  24. 24
    CCHolley says:

    ab @16

    You do realize that the burning of fossil fuels does not add gas molecules to the atmosphere. For every carbon atom combusted one O2 molecule is removed from the atmosphere to form every CO2 molecule that is returned. Net gain to the atmosphere is zero molecules.

  25. 25
    nigelj says:

    AB @16

    “For each molecule of the atmosphere, whatever is its chemical composition (so including CO2 and all GHG or non GHG as well), there is as much probability for a descending SW sun ray than for an upwelling IR ground ray to collide with the molecule, and both rays also have the same probability to be scattered….Conclusion: by adding gases in the atmosphere, there is less incoming SW energy and less upwelling IR energy, thus a net cooling of the global mean temperature. ”

    Except only CO2 and water vapour etc absorb the IR, and this makes all the difference and creates a net warming effect. So the rest of your commentary is wrong.

    “So the measured global warming in open lands can only be attributed to changes in convection, and thus to global deforestation, and not to any addition of gases within the atmosphere,”

    So how do you explain warming oceans? A cooling stratosphere? More warming at night etc. More crank junk science I suppose.

  26. 26
    Hank Roberts says:

    AB @16
    Are you coming up with this error yourself, or are you channeling the confused guy who blogs at “”?

  27. 27
    Hank Roberts says:

    P.S for AB: Google really wants to be your friend. I searched on terms from your question. Here’s a relevant discussion:

  28. 28
    Carrie says:

    I think more equanimity would be an improvement in discussions here.

    4 Dan DaSilva says: “Where is the “firmness” in climate science? Climate science has huge unknowns and the only way to run test scenarios is with models.

    22 Hank Roberts says: “Seriously, guys, read the Eos article, op. cit. above, if you want to follow the scientific conversation.”

    Quoting the EOS article
    “Model simulations of many climate phenomena remain highly uncertain despite scientific advances and huge amounts of data.”

    “Scientists must do more to tackle model uncertainty head-on.”

    “Model uncertainty is one of the biggest challenges we face in Earth system science, yet comparatively little effort is devoted to fixing it”.

    “aerosol radiative forcing of climate, for which the uncertainty range has remained essentially unchanged through all IPCC assessment reports since 1995″

    “Without such reductions in uncertainty, the science we do will not, by itself, be sufficient to provide robust information for governments, policy makers, and the public at large.”

    There is no difference between the meaning of “Climate science has huge unknowns” versus climate scientists saying “Model simulations of many climate phenomena remain highly uncertain”.

    adjective: uncertain – not able to be relied on; not known or definite.

    adjective: unknown – not known or familiar.

    Even if DDS is seen as a contrary denier that’s no justification to distort or deny the obvious meaning of his words when it is no different to what climate scientists have said for decades.

  29. 29
    Steven Mosher says:

    One reason we try to reproduce work.

  30. 30
    Ray Ladbury says:

    In science, “uncertain”=/=”unknown”. Uncertainty implies error bars. Error bars make things manageable. Aunt Judy is being disingenuous with her “uncertainty monster”. DDS is being either disingenuous himself or selectively credulous.

  31. 31
    zebra says:

    Carrie #28,

    There is no difference between the meaning of “Climate science has huge unknowns” versus climate scientists saying “Model simulations of many climate phenomena remain highly uncertain”.

    Sure there is– a (“huge”) difference.

    This is the old business of accuracy v precision, rhetorically framed to be misleading. There’s a “huge” difference between saying “GMST will increase by zero +/- 1C” and GMST will increase by 2C +/- 1C.

    And even “…be sufficient to provide robust information for governments, policy makers, and the public at large.” is essentially rhetorical.

  32. 32
    ab says:

    Steven Emmerson @ 18,

    In his experiments, not only John Tyndall used as a source of radiation some boiling water, but also a “powerful lime light” in order to test the “quality” of the radiation onto the observed effect, as measured with a differential galvanometer made out of thermopiles. What he measured is the “radiant heat” generated at the end of the tube when different gases were added or removed, that is, the energy resulting from the light passing through the tube. What he discovered, by adding or removing some gases, is: 1) for an “obscure source” (IR) a differential in energy at the end of the tube, 2) for a “visible source”, no differential in energy. That is, he demonstrated experimentally that IR energy which does not pass through, because of gases, is negligible compared to the visible energy passing through. In other words, the chemical composition of the air within the tube modifies the energy which is passed through the tube, but the IR energy composant is negligible. That is also what R. William Wood demonstrated in a different way with hot-boxes experiments in 1909: trapping all IR radiation does not increase temperature in hot-boxes, showing effectively that IR energy is negligible compared to the rest of solar ray energy.

    Eli Rabett @ 23,

    Many forms of refraction, reflection, scattering and absorption occur within the atmosphere. The thing is that Tyndall erroneously inferred from his experiments that the differential in energy found with an IR source passing through gases has been absorbed by the gas under the form of heat, and that, without any experimental evidence of it. In fact, we know today that most of the differential in energy has been absorbed by the tube itself through scattering and reemission by the gas, and not by the gas inside the tube under the form of heat, because the heat produced by absorption in a gas is negligible compared with the energy that has been either scattered or reemitted or internally converted by the gas. Thus, 1) the IR energy is negligible compared to visible light, and 2) the heat produced by IR energy is negligible compared to the IR energy that is dissipated by other means.

    CCHolley @ 24,

    Following the experimental evidence, my point was that an atmosphere is a powerful cooling system that limits the energy coming from space, and that adding more gas into it, whatever the gas is, strengthens that effect, while if one removes gas from it, it increases the energy coming from the space. On Earth, the combustion of fossil fuels does not only consist in exchanging one O2 with one CO2, there are also a lot of by products of combustions polluting the air. So we are adding more gases and particles to the atmosphere with combustion, therefore it limits the energy coming from space, and thus cools the climate, but, once again, at the expense of polluting the air, with all the consequences, notably on the health of human beings and of the vegetation (acid rains), which in turn may affect the climate.

    nigelj @ 25,

    As explained in my comments to Steven Emmerson and Eli Rabett above, John Tyndall demonstrated that IR energy is negligible compared to visible energy and moreover, we know today that the heat generated by IR absorption is negligible compared to the IR energy that is either scattered, or reemitted or internally converted (not in heat) by a gas. So GHG may have a tiny warming effect at night, but at daytime, they have a net cooling effect, and cooling is also the daily global effect (combining daytime and nightime effects). So adding more GHG would decrease the global mean temperature, whereas removing them would increase it. Global deforestation implies huge changes in daily thermal amplitude which profoundly modifies heat fluxes and the cycle of water in the atmosphere. Those modifications explain, by convection, the global warming measured in open lands, and also the modification of the distribution of heat in upper layers of the atmosphere. To my knowledge, ocean surface temperatures, as measured by babythermographs, have been steadily stable, oscillating from less than one-tenth of a degree Kelvin above or below the normal between 1955 and 1990. The heat content of oceans have augmented in some parts of the world, and the sea level has rised, but that is evidently due to the melting of ice in the North Pole, not to IR radiation, which is, once again, negligible compared to visible light.

    Carrie @ 19,

    250 new papers per week is a lot to review indeed, and sadly, most of them are clearly based on the incorrect assumption or belief in GHG having the ability to increase the global mean temperature, from the nineteenth century, when they physically can’t. The science is clear, but many scientists are not looking at facts, clear, unambiguous and experimentally demonstrated.

  33. 33

    ab, #32–

    What [Tyndall] discovered, by adding or removing some gases, is: 1) for an “obscure source” (IR) a differential in energy at the end of the tube, 2) for a “visible source”, no differential in energy. That is, he demonstrated experimentally that IR energy which does not pass through, because of gases, is negligible compared to the visible energy passing through.

    You appear to have the conclusion from sentence #1 roughly inverted in sentence #2: what sentence #1 is saying is that IR was absorbed, whereas SW was not. How, then, can zero absorbed SW be greater than some unspecified-by-you-but-apparently-significant amount of absorbed IR?

    I started to critique the rest of your comments, but decided that life is just too short. So let me just say that you are very, very confused, and that the prognosis is that you are going to stay that way, because that is what is really important to you at an emotional level. You are orders of magnitude more interested in being superior to a ‘deluded’ scientific establishment than you are in actually learning something.

    Sorry, but “reality is a bitch sometimes.”

  34. 34

    ab,. #32–

    OK, can’t resist one more comment here:

    …an atmosphere is a powerful cooling system that limits the energy coming from space…

    I think that observations of Lunar temperature are, er, ‘challenging’ to any such interpretation:

  35. 35
    Hank Roberts says:

    Sigh. So “ab” is a believer in the “Sky Monster” story.
    Since that conflates a huge amount of nonsense, trying to deal with it all yet again from this new mouth will become very boring.

    From that Researchgate Q/A page, five years ago, op. cit.:

    Alastair Bain McDonald added an answer
    “Principia Scientific International (PSI) was originally conceived in 2010 after 22 international climate experts and authors joined forces to write the climate science bestseller, ‘Slaying the Sky Dragon: Death of the Greenhouse Gas Theory.’
    The two-volume publication is the world’s first and only detailed refutation of the greenhouse gas effect. According to prominent climate skeptic, Lord Monckton the book soon became ” the talk of the Cancun Climate Conference.”…

    In other words, PSI is a sceptic think tank producing junk science in order to prevent action being taken ….


    “ab” — you’re rebunking old misconceptions long since addressed.

  36. 36
    Jan H. Höffler says:

    The ReplicationWiki is a website created for the discussion of transparency in the sciences. Its database documents availability of data and code for published empirical studies and provides information for methods, data, and software used, which makes it a tool that is used in courses around the world for those who teach methods and search for practical examples. The database also collects published replications. So far it has focused on economics and related sciences but an expansion is planned, and we are searching or partners interested in collaboration. Some studies included are already to climate science, such as

  37. 37

    ab 16: For each molecule of the atmosphere, whatever is its chemical composition (so including CO2 and all GHG or non GHG as well), there is as much probability for a descending SW sun ray than for an upwelling IR ground ray to collide with the molecule, and both rays also have the same probability to be scattered.

    BPL: No, they do NOT have the same probability to be scattered. That is just false. Scattering probability varies radically with wavelength, as does absorption probability, and therefore transmission probability.

  38. 38
    Steven Emmerson says:

    ab@32 I don’t understand your use of the work “negligible”. Tyndall showed that IR absorption by CO2 is definitely non-negligible which, logically, leads to the conclusion that atmospheric CO2 warms the surface of the earth.

  39. 39
    Windchasers says:

    ab @ 16:
    “For each molecule of the atmosphere, whatever is its chemical composition (so including CO2 and all GHG or non GHG as well), there is as much probability for a descending SW sun ray than for an upwelling IR ground ray to collide with the molecule, and both rays also have the same probability to be scattered.”

    Forget whatever Tyndall said — we know that this is wrong. For many gaseous molecules (CO2, H2O, NO2, etc.) the probability of absorbing and scattering a photon *strongly* depends on the wavelength of the photon.

    We’re talking about orders of magnitude difference for H2O’s aborption, between infrared and visible light.

    So yeah: this is just flat wrong. Descending SW photons do not generally have the same probability to be scattered as upwelling IR photons.

  40. 40
    Marco says:

    @ab, #32, Abbot had some things to say about Wood’s experiment:

    Your claim about the CO2-O2 ratio being 1-to-1 isn’t correct. Only coal comes somewhat near (1.17), whereas it is almost 2 for gaseous fuels (e.g. methane)

    You also state that according to your knowledge ocean SST has been stable between 1955 and 1990, apparent measured using “babythermographs”. No idea what those are, but if you meant buoys…those didn’t come into use until around 1980. And there most assuredly is an upward trend from 1955 to 1990. So it appears that your knowledge isn’t quite up to date on multiple aspects.

    You then top it off by claiming sea level is rising due to the North Pole melting. Say what? Yes, it has a little impact (fresh water vs salt water), but the observed sea level rise is too much to be explained by that difference.

    Are you a Poe?

  41. 41
    zebra says:

    Kevin M #33,

    No, he’s correctly describing what happens– what he doesn’t realize is that he is supporting the standard description of GHG effect.

    The sun is the “visible source”,
    The energy passes through the atmosphere,
    It heats the surface (land and sea),
    The surface is the “obscure source”,
    The energy from the surface is absorbed by GHG in the atmosphere.

    ab is exhibiting very confused thinking; it is unlikely that he/she would be able to benefit from even a very patient explanation.

  42. 42
    Hank Roberts says:

    ab: “… heat generated by IR absorption is negligible …”

    Needs to read.

    Try this:

  43. 43
    ab says:

    Kevin McKinney,

    @33, Not at all. You are not reading well if one may point out: 1) IR source with added gas deflects the galvanometer. There is no SW here, just IR source. IR energy that has been dispersed is measured. 2) Visible source with added gas doesn’t deflect the galvanometer. Here, the IR that has been dispersed is shown to be negligible compated to the visible source: IR dispersion is not measured.

    @34, That is exactly what I’m pointing out: the absence of an atmosphere makes a planet, like the moon, faced to sun “boiling hot”, while the other face “freezing cold”. An atmosphere would cool its climate by reducing incoming energy and by distributing the heat through convection. Without atmosphere, no heat distribution, and no limitation of incoming energy makes the temperature extreme both in day side and night side.

    Hank Roberts @ 35,

    I do not know what you are talking about. Personally I do not belong to any think tank or organisation. I’m writing as an individual here. I do not know the group nor the reasons of the group you are talking for not endorsing the greenhouse theory, but personally, mine are clearly expressed here and based on science, not ideology, belief, or politics.

    Barton Paul Levenson @ 37,

    We are not talking about the same thing. Each ray has the same probability of colliding with a given molecule. What happens when it collides (scattering, absorption, partial absorption, etc) is another story which depends on multiple factors: kind of molecules, orientation of the molecule, energy level of the molecule, energy of the ray, direction of the ray, etc…

    Steven Emmerson @38,

    By negligible, in the context of an issue, I mean a value that is so small that it has no physical significance for the issue that is considered. One good example is the first experiment made by Tyndall: an IR source with plain air into the tube. The galvanometer is deflected. Then he pumps out all the air, so that the tube is empty (like in space). Result: no change at all. So the air and its gases have no measurable effect on the IR energy passing through the tube. Thus the IR dispersed by the air is negligible. There is no greenhouse effect trapping energy into the air. Tyndall only measured a significant dispersion effect by replacing the air with plain gas, in high concentration.

  44. 44
    nigelj says:

    AB @32, you relate warming to global deofrestation, but seem unaware warming is happening in areas heavily forested.

    You try to downplay ocean heating, but all NASA Giss data plainly show substantial warming in temperatures, and increases in ocean heat content in recent decades. The kelvin scale is completely deceptive way of portraying temperatures in terms of human adaptation.

    You gave some unintelligible explanation for what is “melting the ice” You see your theory cant account for this, no matter how you massage your theory, but the greenhouse effect easily explains it.

    You are wrong about the Greenhouse effect: read KM’s posts.

    Yet you are clearly incapable of seeing the obvious simple problems like this, which makes you a “crank”. My advice. See a psychologist.

  45. 45
    Hank Roberts says:

    I’d guess “ab” mistakenly thinks that it’s infrared rays from the Sun that heat the Earth.
    And that those rays can somehow be “scattered” away from Earth.

  46. 46
    Carrie says:

    On uncertainty and subsequently transparency and credibility/reliability of past and current Model Forecasts of the Climate System. One paper of thousands published in 2017 is an example of this problem.

    The Impact of Parametric Uncertainties on Biogeochemistry in the E3SM Land Model Daniel Ricciuto Khachik Sargsyan Peter Thornton
    First published: 27 December 2017

    1 Introduction

    Uncertainty about land surface processes contributes to a large spread in model predictions about the magnitude and timing of climate change within the 21st century. Land surface models incorporate a diverse array of processes across various temporal and spatial scales, and include from dozens to hundreds of uncertain parameters. As components of complex Earth system models, these land‐surface models provide crucial information about fluxes of water, energy, and greenhouse gases to the atmosphere and oceans. However, the signs and magnitudes of these fluxes depend on multiple competing feedbacks, and model projections diverge in the latter half of this century (Friedlingstein et al., 2014). Much of the current understanding about land‐surface process uncertainties at regional to global scales derives from model intercomparison projects (MIPs, see, e.g., Friedlingstein et al., 2014; Huntzinger et al., 2013; Piao et al., 2013). However, such MIPs conflate structural and parametric uncertainty, so that combining models or drawing conclusions is difficult (Knutti et al., 2010).

    5 Conclusions

    Although there have been extensive observations of land processes over the past several decades, many land‐surface model parameters remain highly uncertain because they are difficult to connect to measurements, are highly variable, or reflect incomplete process understanding. This parametric uncertainty is a large source of prediction uncertainty in climate models, but it is not often considered in model intercomparison studies or individual model ensembles. Information about the sensitivity of specific model outputs to parameters is valuable for (1) understanding the controlling processes, (2) focusing model development efforts, and (3) for ideally targeting new observations to reduce parameter and prediction uncertainty.

    Posterior probability density functions of these parameters obtained from calibration, in combination with more informative priors from plant trait databases, will enable a formal quantification of uncertainty for land surface model and climate model hindcasts and forecasts. Such uncertainty estimates are essential for policy makers and for the assessment of climate impacts on the Earth system.

  47. 47
    Carrie says:

    One climate science paper, 3 short paragraphs and the words uncertain (uncertainty) are used 10 times and once in the title.

  48. 48
    Carrie says:

    30 Ray Ladbury says: “DDS is being either disingenuous himself or selectively credulous.”

    There are other possibilities, especially if you see DDS as only one example of the tip of an iceberg of hundreds of millions of other normal untrained non-scientists in the public and political classes.

    In their world uncertain means unknown and or not sure. The onus of responsibility for meaning is not on the public’s head. The responsibility rests only in the hands of the scientists (the UNFCCC and the IPCC) no one else.

    While your reliance on the errors bars as a reasonable explanation in a hard technical sense that would apply to some uses of the words Uncertainty (if the world ever got to a point of comprehending that issue explanation) it is not an across the board excuse for all such uses of the word Uncertain in Papers or when spoken publicly by the science community to the public and policy makers at large.

    Sometimes it does mean “we do not know”

    and/or “it’s the best educated guess we can make at this time based on the limited incomplete knowledge we have.”

    Quickly followed by “we need to do much more data collection from observations and do more research”

    So Ray, how I see it while acknowledging error bars do apply in some cases it does not explain away the IPCC Scientific papers pronouncements that an Summer Ice Free Arctic will “likely” not occur until the 2090s, changed a few years later to the 2050s, brought forward soon after to the 2030s, while recent observations and continued rapid warming suggests that might shift to the mid-2020s very soon or in the IPCC AR6. Who knows? We’re uncertain at the moment. :-)

    What I am saying more simply is that is one hell of a huge error bar that can accommodate a variation of one climate variable ASIE from the 2090s back to the 2030s in a geological instant.

    Even if the climate science community is doing the absolutely best they can this does not make any difference to everyday normal people having doubts when the forecasts do keep shifting across decadal timescales. Not when the words Uncertain etc are repeatedly used in media reports, in lectures by scientists on youtube, at Congressional hearings, and in almost every single climate science paper ever published.

    Normal people cannot be blamed or found to be at fault for having doubts about Models, forecasts and more. To me it is quite reasonable and understandable that they are. Treating them all like morons and disingenuous liars is no solution at all.

    The problem is the science and the scientists. They are 100% responsible for the solution – not DDS not Victor not the Republican party or Fox News et al. YMMV fine.

  49. 49
    David Young says:

    Yes S. Mosher, replication is always good. The problems here are really structural. There is little incentive to do it and the bigger payoff is to produce yet more positively biased results. Academic science is really riddled with unreliable results as the major journals such as Nature and the Lancet have editorialized about. There is a new paper on preregistration of trials that is very disturbing.

    Basically, allowing researchers to decide after the fact which effects to publish leads to a huge positive in the literature.

  50. 50
    nigelj says:

    Carrie @48, yes climate science has some elements of uncertainty, and we should just call it what it is. However you go on to suggest that if only scientists could remove all that uncertainty, the denialists would become believers. It might sway a few people in the middle of the debate at best, but will have no effect on people like DDS or Victor. Their denialism is deeply rooted in vested interests, political ideology, and psychological issues or crankiness.

    And once people take firm political positions change is difficult. Even if the science was 100% certain the denialists will just move on to “CO2 is plantfood” etcetera. The problem is mainly the denialists, not so much scientists.

    There’s another issue in relation to all of us ordinary folks. Humans are status seekers, and we demonstrate this through materialism ( to varying degrees of obsessiveness), and climate mitigation requires we reduce our materialism, so obviously this is challenging, however there are alternatives to materialism.