Climate Science Glossary

Term Lookup

Enter a term in the search box to find its definition.

Settings

Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).

Term Lookup

Settings


All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Home Arguments Software Resources Comments The Consensus Project Translations About Support

Twitter Facebook YouTube Pinterest MeWe

RSS Posts RSS Comments Email Subscribe


Climate's changed before
It's the sun
It's not bad
There is no consensus
It's cooling
Models are unreliable
Temp record is unreliable
Animals and plants can adapt
It hasn't warmed since 1998
Antarctica is gaining ice
View All Arguments...



Username
Password
New? Register here
Forgot your password?

Latest Posts

Archives

The nature of authority

Posted on 23 July 2010 by gpwayne

Guest post by Graham Wayne

In a recent post, John Cook wrote:

"When it comes to complex science, whether it be climate science or heart surgery or how a plane manages to stay up in the air, we defer to the experts who do this stuff for a living. Why? Because they know every nook and cranny of their area of expertise.

Well, I think there is another reason why we should defer to the experts, but we have to be clear about what that deference entails, for words can be misleading. Sometimes, the dual nature of a word leads us to confuse one thing with another. Consider the word authority, for example.

I started out as a musician. I remember meeting plenty of older players, and they would tell me things from time to time. They didn’t equivocate, nor did they leave any room for doubt in the way they put things. Frankly, they sounded just like my dad, and equally certain. Since he was usually wrong, I assumed these musicians were simply as dogmatic as my old man, and probably talking as much bollocks as he did. ‘Don’t tell me what to do’ I would say, mostly to myself. As far as I was concerned, what they knew was like what my father thought he knew – assumptions, dogma, convention. What right did they have to insist certain things were a particular way, and had to be? I was young, ready to rebel, to change things. The world didn’t have to be like they said, like my father said. I could reshape the world in my own image. I acknowledged no authority but my own, and anyone who told me what to do or how to do it could sod off.

Fast forward 20 years. I’m talking to some young musician, and I have that self-conscious experience of listening to myself, and what I’m saying. And bugger me if I don’t sound just like them, just like my dad. What on earth has happened? How did I become so bloody sure of myself?

The answer is that I did the work. In those intervening years, I paid my dues (rather over-paid, I suspect, due to a certain intransigence). I gained experience, I practiced, I learned from mistakes, I worked hard, and with each passing year my knowledge was improved by my education. Out of these experiences, I gained something unexpected: authority over the subject matter I had spent so much time studying. There are rules, and you cannot break them except at your cost (and the cost of your audience). These standards must be met, else you are doomed to be second-rate.

There are, it turns out, inviolable precepts. If you aspire to excellence and consistency, you are obliged to both acknowledge and obey the precepts that apply. Those who think they can get away with it, take a shortcut, cheat a little here and there; they always discover the same thing – exactly as I did. You can’t fool your audience, not for a minute, and it is equally hard to fool yourself. The work must be done and the dues paid, no matter what discipline you seek to acquire or what reasons you have for doing so. Success is built on the foundations of discipline and experience; once you have these attributes, there is nothing that can undermine them because you know they are not arbitrary, they are not personal. I know now, from discussion and experience, that all the people I admire have learned the same thing, and applied that knowledge uncompromisingly. They respect the rules of engagement and obey them, because they are not optional and you ignore them at your great peril.

So, in this personal example, we can use a synonym for authority: we can call it mastery. In art, in science, in business; in any sphere, if you do the work – all of it – and do it diligently, you gain mastery over your subject. Consequently, when I speak about playing or performing, I am not equivocal – I’m telling it like it is. I’ve had students who argued with me, but they lost every argument, because I had paid dear for my knowledge, as did all my peers, and what I gained was a profound certainty in that which I can be certain about, because this kind of authority is tested under fire - every single time we enter the fray. Since what I learned never let me down – not ever – it becomes more than a theory (and when I ignored the rules, I always got my arse kicked). It becomes like the rules of physics, unbending and subject to no negotiation whatever. When I talk about the knowledge I have gained from such effort and discipline, I may end up sounding like my dad, but it turns out he knew a thing or two after all.

***

The other kind of authority is the kind that children resent when they are told to go to bed or wash behind their ears. It is the arbitrary authority of those bigger than us, stronger than us, richer than us, more powerful than us. Teachers deploy this authority. So do bosses, policemen, higher ranks in military establishments; anyone whose position in the pecking order gives them the notion they have the right to tell us what to do. Sometimes, we work for a boss who is smart, so perhaps we don’t mind him or her telling us what to do (and the wages generally provide sufficient leverage to mute our dissent).

What we resent is the arbitrary notion that underlies this authority. Who are these people? How do they assume they are somehow better than us, when they offer nothing more than a bribe or a cuff round the ear? That isn’t authority, it is bullying. Isn’t it? Taking advantage, in other words; getting us to comply with their wishes whether we like it or not, making us do what they want just because they say so. Just like scientists and their bloody climate change theories, right? Who gave them the authority to tell us what to do?

Well, nobody gave them authority. They earned it, and it isn’t authority over us, it is authority over their subject matter. Scientists have to struggle up a learning curve so steep it is beyond the comprehension of most lay people. To start with – before they can lay a hand on a test tube or a microscope – they must learn everything that has gone before. This can take a decade or more, and the rewards are not only paltry, but often unreliable, since many will not ever make the grade or the salary commensurate with all that work they put in.

After what we might call a very long spell in boot camp, after they have negotiated the training courses comprising several centuries of highly detailed work; only then may the fledgling scientist stand upright on the shoulders of the giants who preceded them, and take a look around them. Only then may they start to work on a theory of their own, or collaborate with others whose theories merit investigation. Even to call yourself a research scientist, it is necessary to gain that mastery, that authority, that uncompromising discipline that is defined by the scientific method. And some of these scientists are studying climate change.

————————–

Scientific authority should not be confused with the authority of parents, or teachers, bosses or politicians. I am constantly amazed at the way lay people dispute science, by attributing to it some arbitrary notion of authority. When all other forms of authority seem to be arbitrary, perhaps it is understandable that, when science speaks with an authoritative voice, it seems equally subjective or capricious. When hierarchical authority is exercised in the pursuit of an agenda – political, legal, caring, educative or whatever – its aims may be equivocal, self-serving or arbitrary, where a different aim or agenda would be equally valid.

Science isn’t like that: it tests what it find ruthlessly and repeatedly, for there is only one right answer to any scientific problem, only one theory that is wholly correct. It is often overlooked that scientists cannot afford to promote myths, or self-serving results. Scientific knowledge is a hierarchy too, where the last paper on a subject becomes part of the next paper, through the process of citation. Nobody wants to do all the work all over again – reinventing the wheel – so all scientists have a vested interest in making sure all the work that is incorporated into the body of science is scrupulously accurate and solid, because they may well base their next research project on the same work, the same given, the same method. Bad science puts all scientists at risk, which is one reason why all scientists are so keen to root it out.

When science speaks with authority, we should respect it, not resent it. And we should not be afraid to accept that there are people who are smarter than we are. One common tone I find in discussions about science is generated by a strange notion of equality, a rather topical political trope where all people are rendered so damn equal there isn’t any individuality left. There are a lot of people smarter than me, and it does not demean me to recognize this, or acknowledge them and their achievements. Of all the branches of human endeavor, science is one of the most intellectually demanding and difficult. What these people do astounds and humbles me. That they are cleverer than me at science does not make me less important as a human being. It does remind me that self-importance is a vice we can ill afford, especially when we try to ignore those who speak with genuine authority.

Check out more Graham Wayne action at gpwayne.wordpress.com.

0 0

Printable Version  |  Link to this page

Comments

Prev  1  2  3  4  Next

Comments 101 to 150 out of 170:

  1. johnd at 04:21 AM on 24 July, 2010 ”…clouds have been determined as having an overall nett cooling effect…” One needs to be careful. As Palle et al (2006) have described an albedo change due to secular cloud variation doesn't necessarily imply a surface temperature response since clouds have warming ("heat trapping") as well as cooling (albedo) effects. Palle have more recently (Palle et al., 2009) described the total albedo variation (expected to be mostly cloud-related) and found that this has been pretty trendless during the last 10 years. E. Pallé et al (2006) Can Earth's Albedo and Surface Temperatures Increase Together? Eos Trans. AGU, 87(4), doi:10.1029/2006EO040002 link to paper Palle et al. (2009) Inter-annual variations in Earth's reflectance, 1999-2007 J. Geophys. Res. 114, D00D03 link to abstract ”But there is still that indecision as to whether temperature is a function of clouds or clouds a function of temperature. We may find that there is rather little relationship between Earth temperature and cloud cover, largely due to the fact that a warmer atmosphere maintains a higher concentration of water vapour ( KR has described this), and so cloud cover has no necessary systematic relationship with temperature. After all the Earth has warmed by an amount (0.8-0.9 oC) since the middle of the 19th century, that supports the conclusion that the climate sensitivity cannot really be below 2.0 oC (i.e. the temperature rise is that expected even without factoring in the slow response times of the climate system and the cooling effects of atmospheric aerosols, although one should consider non-CO2 contributions like nitrous oxides, methane and black carbon). So there pretty much has to be a positive feedback from water vapour as predicted by our knowledge of the greenhouse effect. Otherwise one might ask: “where is this supposed cooling effect of clouds”?! So far (as far as I’m aware) there is only one direct analysis of the cloud response to warming surface temperatures. This study (Clement et al., 2009) tends to support the conclusion that the cloud feedback is a positive one (i.e. a warmer equatorial sea surface results in a reduced cloud cover). However more data is needed on this. A. C. Clement et al. (2009) Observational and Model Evidence for Positive Low-Level Cloud Feedback Science 325, 460 – 464 link to abstract Likewise many of the determinations of climate sensitivity (Earth equilibrium surface temperature response to increased greenhouse gas concentrations) are phenomenological, in that they assess the relationship between CO2 and surface temperature during ice age transitions or during the deep past. In these analyses all of the feedbacks (whether positive or negative) are “lumped in”. Since these analyses pretty uniformly find a climate sensitivity near 3 oC, it’s difficult to support a significant negative cloud feedback (unless there is a positive feedback we’ve not yet discovered). R. Knutti and G. C. Hegerl (2008) The equilibrium sensitivity of the Earth's temperature to radiation changes Nature Geoscience 1, 735-743 link to paper johnd at 09:26 AM on 24 July, 2010 ”Thus it is reasonable to expect that as atmospheric water vapour content varies, so too would that of clouds.” No that’s not a “reasonable” expectation. The fact that a warming atmosphere (so far) tends to maintain a near constant relative humidity means that cloud cover doesn’t necessarily vary with water vapour content. A warmer atmosphere maintains a higher water vapour content than a cooler one, and there is no reason to expect the extent of cloud cover to vary with temperature. That’s not to say that there may not be more rainfall in a warming world (Allen et al. 2008). But remember that rain clouds are just a proportion of total clouds. We expect in a warming world that rainfall will decrease in the equatorial regions of the Earth (consistent with Clement et al’s observation of reduced cloud cover above warming sea surface) and we will have increased rainfall at higher latitudes. That’s pretty much what is observed (Zhang et al, 2007). Thus during the 20th century, the latitude band from around the equator to around 30 oN has become drier (reduced rainfall; enhanced drought) as the Earth has warmed during the 20th century, much as predicted. This latitudinal band of reduced precipitation will widen as the Earth continues to warm (and so, for example, Amazonia is expected to dry progressively towards the South as the Earth continues to warm). The higher latitudes (especially above 50o N and below 10 o) have seen enhanced precipitation. Global warming and shifts in precipitation regimes is expected (and already observed) to lead to amplification of extreme precipitation events (e.g. Allen et al. 2008). X. Zhang et al. (2007) Detection of human influence on twentieth-century precipitation trends Nature 448, 461-465 link to abstract RP Allen et al. (2008) Atmospheric warming and the amplification of precipitation extremes Science 321, 1481-1484 link to abstract
    0 0
  2. johnd at 08:55 AM on 25 July, 2010 "If CO2 levels remained apparently constant from the ice age until the industrial revolution, how could the inter-glacial warming occur if CO2 works the way it is postulated?" It's not obvious what you mean by that johnd. Can you expand on your point or reframe it? After all CO2 levels clearly didn't remain "apparently constant from the ice age until the industrial revolution". The pre-Holocene "ice age" [CO2] was around 180 ppm, and the pre-industrial [CO2] was around 270 ppm. Did you mean something else??
    0 0
  3. Graham, This is an excellent piece. I will be forwarding to many.
    0 0
  4. johnd:"shawnhet at 04:31 AM, it applies as the overall NETT effect over longer time frames. As skywatcher makes mention of, depending on the seasons, types of clouds and regional conditions, the shorter term effects are much more complex and variable with the opposite occurring. It is the balancing out of all these factors that determines to NETT effect which is what is relevant in climate time frames." At the risk of repeating myself here, *if* higher temps lead to more WV in the air which in turn leads to more cloudiness and a reduction in temps, then there are only two ways I can think of for the observed inverse relationship btw cloudiness and temps to hold. Either this relationship is masked by some sort of natural variation OR the temperature feedback from increased cloudiness is so strong as to completely cancel out the original temperature rise. Personally, I don't think the latter possibility is at all likely. Perhaps an example will suffice help here: Imagine a world with no natural cloud variation, such that a 1C initial warming causes an increase in cloudiness of x% which reduces the temps by 0.5C in that circumstance, the relationship btw cloudiness and temps will be direct, right? Now assume that over top of that we add a natural decrease in cloudiness of -2x%, the temps will increase and the cloudiness will decrease, but they will not decrease *because* of the temp increase, but rather in spite of it. I don't disagree that seasons can make things more complicated. KR, I don't disagree that the observed relationship btw cloudiness and temps over recent history appears to be inverse. My point is whether this relationship should necessarily be consistent. chris:"”Thus it is reasonable to expect that as atmospheric water vapour content varies, so too would that of clouds.” No that’s not a “reasonable” expectation. The fact that a warming atmosphere (so far) tends to maintain a near constant relative humidity means that cloud cover doesn’t necessarily vary with water vapour content. A warmer atmosphere maintains a higher water vapour content than a cooler one, and there is no reason to expect the extent of cloud cover to vary with temperature." Well, I suppose it depends on your definition of reasonable here ;), but clearly temperatures a couple of kilometers above the Earth's surface aren't "maintained" - rather they are always heating or cooling. Assuming constant RH, cooling of 1C will condense more water from warmer air than cooler air. Since condensing vapor is one of the chief components of cloudiness, I agree with the idea that *everything else being equal* increased temps should increase cloudiness. Cheer, :)
    0 0
  5. DougB #91 I agree that the 'leakers' of the Climategate emails had an agenda - either a closet skeptic(s) or a disgruntled insider assembled the files of emails. Corcoran says he read all the first 5 years and they form a coherent narrative. He says the more recent emails are obviously hurriedly assembled and difficult to follow. Corcoran acknowledges that they were deliberately released prior to Copenhagen for maximum effect. The critical issue is their authenticity - and that has not been challenged by the scientists involved. The emails revealed however that certain scientists were themselves planning a blitz: quote: "The last emails were sent between Nov. 10 and 12 this year (2009), five days before the whole cache was stolen. One of those last emails outlines an attempt to orchestrate a media blitz by scientists at the American Geophysical Union annual meeting. The strategy was aimed at shaping public opinion going into the Copenhagen talks that ended yesterday." endquote Maybe they were simply 'outblitzed'. Doug your argument tries hard to dismiss the emails as a 'selective dataset'. This is a strawman. They never constituted a 'dataset'. They are a valuable record of the behind the scenes discussion and modus operandi of key players in the AGW story. You also have to consider the difficulty of the leakers slanting the narrative by selectively quoting emails and leaving out others. The narrative for the first 5 years according to Corcoran is coherent - so leaving out vital 'AGW friendly' emails would tend to destroy the narrative, which those involved agree, are the scientists own words. If there are emails missing which would significantly change the story - the scientists involved should have released them in their own defence. If they have - point me to them. I think the shock to everybody with an interest in climate science, was the attempt to present to the world a front of robust high quality research; when in fact there was significant internal dissent, unprofessional personality clashes and far greater uncertainty hidden in the private communications.
    0 0
  6. Bottom line, Ken: Whatever person or group appropriated and published the emails thought it best we not see all of them. It's a familiar odor, no more honest than attempting to break into RealClimate's server to exploit it as a publication site, the perpetrator's first choice for dissemination. All the hallmarks of a juvenile political stunt, but unfortunately slipping into the minds of a receptive and credulous audience not known for critical thinking skills, hence the gullible acceptance of a careful set of selected quotes as a "coherent narrative." Your assertion that the victims of the perpetrators should defend themselves by publishing the material redacted by the perpetrators is frankly bizarre.
    0 0
  7. By the way, Ken, every time a "skeptic" brings up the ancient, dusty emails it's essentially an admission that such a "skeptic" does not have anything useful to say about the actual science under discussion. Gossip is not science.
    0 0
  8. At least Ken had the decency to put the word 'leakers' in quotes. I'm not much fussed whether it was an inside job or not. Theft is theft, illegal is illegal. I tend to use the prism of theft v. leak to make an initial assessment. If someone uses the word 'leak' rather than theft, I'm unsurprised to find that the following text contains a fair amount of silliness.
    0 0
  9. Ken #105 You must be short of substantive argument if you're trying to recycle this old discredited material. None of the climate conrarians attempts to claim nefarious activity within the CRU and their collaborators has met with much success. The enquiries have pretty much universally found that the allegations made by contrarians were without substance. You can of course recycle some more conspiracy theory claiming an inside job put-up, but this will discredit your argument even more :).
    0 0
  10. DougB #106,107, Adelady #108, kdkd #109 I was happy to leave 'Climategate', but DougB wanted to kick along. Corcoran summarises the story pretty well here: Quote: "The emails portray embattled scientists fighting desperately to interfere with official FOI processes. One now widely-circulated email, by Mr. Jones, asked Mr. Mann: “Can you delete any emails you may have had with Keith re AR4? Keith [Briffa] will do likewise. He’s not in at the moment — minor family crisis. Can you also email Gene and get him to do the same? I don’t have his new email address. We will be getting Caspar to do likewise.” In this email, Mr. Jones is asking key scientists who worked on AR4 — the 4th Assessment Report on the science of climate change produced by the IPCC in 2007 —to erase all emails related to that report." endquote One might ask why these emails needed to be erased if those involved felt they were just a bit of honest disagreement between professionals acting in good faith. Clearly they felt there was something to hide if subject emails were revealed in FOI requests. As for legality or illegality m'lady, destroying material to avoid an FOI disclosure might indeed be illegal too. These days whisteblowers are being encouraged and protected in many jurisdictions so that malfeasance is exposed. No doubt the information or documents thus revealed are regarded as theft or breach of confidentiality by those exposed by whistleblowers. I was more interested in the attention drawn to Dr Trenberth's paper and subsequent discussions - even something on the wide error bars on cloud and aerosol forcings.
    0 0
  11. Ken Lambert, give it up : those emails (which you prefer to believe were 'leaked' - why is that ?) have turned into fool's gold for the so-called skeptics. However, like a dog gnawing away at it's manky bone, some people just cannot seem to let go. I still think it's down to embarrassment, mainly - embarrassment that the so-called skeptics, who were led to believe that the emails proved AGW to be a scam and a conspiracy, have now realised they were had by their very own trusted blog gurus.
    0 0
  12. #96. Good quote from Charles Darwin. But just to note, Mr Darwin was also a gradualist, who certainly didn't believe that significant geological changes (such as catastrophic climate change) occurred within the time frame of human lifetimes. He strongly opposed Cuvier's assertion that mass extinctions occured in the geological record. (Darwin was wrong). He strongly opposed the notion that climate, and its effects on biota, can change rapidly. (Darwin was wrong). Both he and Lyell believed Earth history was fundamentally 'stable' or uniform, and not prone to catastrophic 'convulsions' and such like, and therefore they rejected any notion that massive species turnovers ever occurred (They were wrong). The gradualists were fundamentally opposed to the catastrophist assertions that both significant geological 'upheaval' and biological evolution could occur within the general time frame of human history. (This was partly in response to the 'flood' catastrophists). Various geological debates between catastrophists and gradualists have been going on for several centuries. In biology, gradualism has generally gained predominance, however there are major exceptions (eg punctuated equilibrium and debates, mass extinction events etc etc). However, I certainly think that contemporary thought on climate change has been over-dominated by 'catastrophist' assumptions (without those advocating AGW actually realising that that is what they are, and that is where their assumptions on earth dynamics lies); some redress is definitely needed. Charles Darwin,as a die-hard gradualist and staunch supporter of Lyell's uniformitarianism, himself would have been a skeptic of AGW, I suspect.
    0 0
  13. Thingdonta, Most of us agree with Darwin that NATURAL changes are usually gradual. AGW is anthropogenic, so it is fundamentally different. I think Darwin would follow the data, like the majority of scientists, and agree AGW is a problem. Since he is dead we will never know for sure.
    0 0
  14. "Charles Darwin,as a die-hard gradualist and staunch supporter of Lyell's uniformitarianism, himself would have been a skeptic of AGW, I suspect." The connection is not so clear (to me), since AGW is by definition not a process of Nature.
    0 0
  15. to michael sweet Looks like we were thinking something similar, however why should Darwin think AGW is a problem? Evolution guarantees survival of the fittest.
    0 0
  16. Nature innovates, in fact innovated a force that could for instance eliminate the ozone layer and thus inflict what by some measures would be a swift and catastrophic change in conditions on the surface of the planet. Yet by chance this same force was invented as self-aware and thus capable of changing its own behavior at will, thereby reversing its previous course with regard to removing the ozone layer. Marvelous, when you think about it.
    0 0
  17. Sweet, Michael..... Given that Darwin was a consummate logician, I take a different stance to yours and submit to all, that he would have pronounced the AGW agenda as the most intellectually flawed load of B-ll-x he'd ever encountered.....more the remit of the snake-oil salesman than that of the scientist, formerly respected, until those times, as a pillar of rectitude and intellectual integrity, supporting the grand edifice of enlightened European civilisation.
    0 0
  18. To doug_bostrom "Yet by "chance" this same force was invented as self-aware" Somewhere I heard that intellegence evolved through generations of escalated deception.
    0 0
  19. AWoL at 03:42 AM on 26 July, 2010: Why would a logician assume that multiple, independant lines of evidence would indicate an agenda? That's, erm, not logical. ;)
    0 0
  20. Darkskywise. There's a word doing the rounds amongst the great unwashed, of which I am a member, and that is "monopsony". And to the great unwashed, it explains why "multiple, independant(should be independent), lines of "evidence" do indeed, indicate an agenda. Maybe no likee, but it is, erm, LOGICAL.
    0 0
  21. RSVP:
    "Charles Darwin,as a die-hard gradualist and staunch supporter of Lyell's uniformitarianism, himself would have been a skeptic of AGW, I suspect." The connection is not so clear (to me), since AGW is by definition not a process of Nature.
    The principle of uniformitarianism would lead one to believe that since CO2 from natural sources leads to forcing and feedbacks responsible for about a 33C rise in temperature from what we'd see on earth without it, that adding CO2 from whatever source will lead to temps rising even higher. The non-uniformatarian claim is that just as people start adding significant CO2 to the atmosphere, either it stops being a GHG, magic negative feedbacks kick in, etc and therefore doing so can't warm the planet.
    0 0
  22. AWoL, your term "monopsony" is cute and appealing but explains nothing, certainly not in a logical fashion, instead leans on an unproven assumption depending on a hugely unlikely set of imaginary circumstances. You'll need to show in detail how at least a plurality of independent lines of scientific inquiry and results are incorrectly conducted and derived in order begin supporting what I take to be your belief that a broad swathe of scientific knowledge is "snakeoil." Don't get your hopes up; most of the evidence indicating a problem with anthropogenic global warming has roots quite far removed from the theory itself. By the way, circumspection is arguably a key trait of skepticism.
    0 0
  23. One of the fundamental errors of the AGW concept lies not in el nino this, or ocean acidification that, but of the misinterpretation and misapplication of the Stefan-Boltzmann constant. The model is miles off for temperatures relevant to living things. It is misinterpreted by pro-AGWs and anti-AGWs alike. Yet the whole premise of AGW is founded on this utterly ludicrous(for low temperatures) law. In future, when wishing to solve a problem of radiative heat transfer, remind me to consult a Nigerian witch-doctor, for he is just as likely to get the right answer as a climate scientist.
    0 0
  24. AWoL at 04:50 AM on 26 July, 2010: "(should be independent)" Thank you, Oh Great Unwashed. ;) Since English isn't my native language (which is Dutch), a few spelling errors are bound to creep in every once in a wile. Sory.
    0 0
  25. AWoL presumably you can explain to us "the misinterpretation and misapplication of the Stefan-Boltzmann constant"?
    0 0
  26. Replying to Doug Bostrom, post 125, I'll have a go.1st is the fact that the constant(S-B) deals with a plane surface and not a 3-d body.The limitations of this became apparent at the time of the moon landings.The difference between the theoretical predictions of Lunar temperatures and actuality were gross. Trouble is that things get even worse when you get to phenomena involving radiative transfer at temperatures conducive to life, say circa 0-100degCie planet earth.The figures for radiation emitted for temperature bear no relation to reality, yet they are used to demonstrate a "greenhouse" effect. Apply a modified constant for lower temperatures and it turns out that the surface temperature of the earth,devoid of atmosphere,far from being -19degC would be, when illuminated by the sun, midday,at the equator in the order of 50degC. So the atmosphere cools the surface by day and reduces to a variable degree(largely dependent on cloud cover,and not CO2) by night.One thing that is for sure is that CO2 does not act like a greenhouse, which raises temperature by limiting convection, and not by entrapment of radiation. In other words the employment of the word "greenhouse" is entirely inappropriate, and its continued usage has nothing whatsoever to commend it other than "tradition"
    0 0
  27. No go, AWoL. Here's how somebody knowing better than you or I describes the situation w/regard to Stefan-Boltzmann and non-plane surfaces: ...any differentiable surface can be approximated by a bunch of small flat surfaces. So long as the geometry of the surface does not cause the blackbody to reabsorb its own radiation, the total energy radiated is just the sum of the energies radiated by each surface; and the total surface area is just the sum of the areas of each surface -- so this law holds for all convex blackbodies... If you care to have another go you may try rewriting the science starting here. The moon is of course substantially convex, does not reflect on itself in a significant way. The rest of your point w/regard to Stefan-Boltzmann appears to be entirely fictitious. "Apply a modified constant..." is simply making things up to suit your rhetoric. If you want to try changing the constant, start here. Your "greenhouse" remark is just as sophomoric as your correction of DarkSkywise's spelling, pointless and of no utility to this discussion. The term is an unfortunate semantic hangover and has no bearing on the science in play here, the fact you refer to it is diagnostic of naivete on this subject.
    0 0
  28. JohnD - but you are trying to infer information from that data which I suspect is imappropriate for that purpose. It is inappropriate to make such attempts without consultation with the data collectors. Furthermore it is in direct conflict with published analysis the same problem. "given they are significant factor in the energy balance" - but are they? They are both positive and negative feedback and may be close to neutral in the energy balance. You cant develop proxy but you can infer past climate sensitivity and these studies do not indicate the low sensitivity that you are trying to imply. As to the CO2 effect in interglacial warming. Huh? Models with conventional understanding of CO2 and other forcings work do not have a problem reproducing past paleoclimate from estimated forcings - see the various papers in the IPCC. They have sensitivity of around 3.
    0 0
  29. Well at least we agree on one point, Mr Brostrom, "that the moon is substantially convex and does not reflect on itself" very interesting. Stefan-Boltzmann says that a squ mtr of material of typical emissivity of 90-95%,at 27degC will beam out something of the order of 459 watts. That's the energy of nearly 5 light bulbs of 100watts each. Does it? Check it for yourself by using night vision equipment. Dead simple.It's wrong. The prediction does not match the result. The constant is a theoretical concept and simply,in it's present form does not match the real world. Yes I would like to see the constant modified and I wish some physicist would hurry up and get on with it. As to the greenhouse remark. I think I made a very valuable contribution to the AGW debate by pointing out that the improper use of this term implants a totally erroneous idea in the mind of the layman and the politician.The world of science should stop using it if it doesn't want to be accused of the employment of slick and disingenuous language used by advertising agencies and snakeoil salesmen.
    0 0
  30. Sorry, AWoL, I've done what I can. Cheerio.
    0 0
  31. Ken Lambert - I think the stolen emails, to have any credibility at all, need to be complete. Maybe the missing bits are exculpatory, maybe they are damning - we don't know. But we do know the thief had an agenda, and by not including the full set, they manipulated the message - exactly what they accuse the legitimate scientists of doing!
    0 0
  32. AWoL, "night vision equipment" is not the way to measure thermal radiative flux. You want a laboratory thermal radiometer, and with one you will verify that yes, S-B is correct. Frankly, I have to admit I'm astonished by what I see on this website right now. In another thread RSVP is questioning basic laboratory measurements of the spectral properties of gases that have been known since the 1850s. In this thread, AWoL is rubbishing the Stefan-Bolzmann constant, which was first measured in the 1880s (?). That is not skepticism. When something has been measured and applied by scientists and engineers for over a century, and is the building block for a great deal of subsequent science and technology, a skeptic demands very strong evidence to overturn it. As far as I'm concerned, if you come on this site and want to claim that Stefan-Bolzmann is wrong, or Maxwell's equations are wrong, or CO2 does not absorb longwave radiation, you need to present a detailed and explicit case that lays out exactly how and why every physicist who's worked in this field since Tyndall has been mistaken. You need to specify exactly what the problem is. Don't just waste everyone's time by tossing out ill-formed ideas or crackpot hypotheses. And of course, if you can disprove basic tenets of radiative physics, you shouldn't be wasting your own time doing it here. Write it up and submit it to Science or Nature. You will be famous, and future generations of scientists and engineers will be eternally grateful to you. Until you do that, though, posting claims here that a century's worth of physics or chemistry is wrong will inevitably tar you with the label of crackpot. And nobody wants to see this site get mired in crackpottery.
    0 0
  33. May I suggest that, given that we know people ARE mistaking the scientific authority that comes from having mastered the subject matter and mistaking it for the bullying kind, that we move on to the next question? I.e., what do we do about it? Sure we can pronounce the problem identified and go on arguing about the minutiae about little parts of the problem. Or, we can ask the people who are used to dealing with that world and see what might work. Note that there are some parents and nannies who are phenomenal at managing even the most intractable kids. There are people who are so good with animals that with a little work they can get even the most hardcore dog to behave. And -- there are political consultants and scientists who do nothing but study and teach politicians and interest groups on how to persuade people of a particular point of view. I submit to you that they are quite good at it. Any thought of drawing on their "mastery" of the subject? After all, the opposition seems to be mostly led by people in that line of work and they are eating your lunch. Re the need to behave as political animals, the great mass of posters on these science blogs and message boards seem to be like the OP who as a kid heard from the older musicians what works and thinking it's all BS. Perhaps it's time for guest posters from the world of politics, PR or public opinion to give advice on how to turn the tide?
    0 0
  34. #129 AWoL at 10:11 AM on 26 July, 2010 Stefan-Boltzmann says that a squ mtr of material of typical emissivity of 90-95%,at 27degC will beam out something of the order of 459 watts Yes, something like that. A perfect blackbody (e.g. a hole leading to a large cavity) would indeed radiate 459.3 W/m2 at 300 K. This 300 K is only 26.85°C, not 27°C, but that's not a big deal. And the hole's emissivity is 100%, not 90-95%. A material of 90% emissivity would radiate 414 W/m2 at 27°C. You don't even need a laboratory thermal radiometer to see this. Just imagine a ball of 56.4 cm diameter (surface area 1 m2) filled with 27°C water and left in interstellar space (temperature 2.725 K, that is less than -270°C). If you want to keep its temperature unchanged, it is entirely reasonable that more than 400 W continuous power is needed for heating. Or if interstellar space is too far for you, hang the ball in a large space filled with 0°C thermal radiation. You can apply a thin rope to a branch in a dry winter night with low clouds and temperature around freezing. The background radiation in such an environment is 315.7 W/m2 (it is 3.1 μW/m2 in interstellar space). In this case, if the emissivity/absorptivity of the ball is 90%, you only need 130 W to keep it at 27°C. Of course you'd need a bit more, because now it is surrounded by (dry) air and it also cools the ball, but heat conductivity of air is low, so in calm weather most of the losses are radiative. If it is still not personal enough, try to calculate how much do you have to eat to stay alive in such an environment naked. The surface of adult human body is about 2 m2, skin's emissivity is close to 100% and you should not let your skin temperature go too low, otherwise it dies (gets black and peels off your flesh). Tibetan monks do something like that. It is called tumo and it keeps the body warm in extreme cold. But even they need plenty of tea with yak butter to resupply the energy lost. Fat has 37 kJ/g, therefore 40-50 g butter can supply more than enough heat for an hour for a well trained body. Of course if there is also a chilly wind, more energy is needed, because a lot more air gets into contact with skin, and even if it has low specific heat and low heat conductivity, contact losses can exceed radiative ones.
    0 0
  35. BP writes: You don't even need a laboratory thermal radiometer to see this. Well, you need either a radiometer or a mathematical model to quantify it. Since he was voicing disbelief in the model, I suggested the radiometer. I do like your visualization though.
    0 0
  36. #133 dcwarrior at 23:57 PM on 26 July, 2010 Perhaps it's time for guest posters from the world of politics, PR or public opinion to give advice on how to turn the tide? No way, man. It is supposed to be a science blog, not a political one. Neither it is a PR device. Read the Comments Policy please. More than one of my comments even slightly touching on political issues got deleted. And I truly wish all such comments have the same fate, even if they came from the other side. In this respect moderation policy is not perfect yet, as there are also posts which have a clearcut political edge, still, they get published here. But it is a shortcoming, not a strength. If you want to turn the tide with such devices, all the authenticity earned so far is thrown into the wind.
    0 0
  37. Thingodonta:
    Good quote from Charles Darwin.
    I chose that quote because it was Darwin's formulation of the Dunning-Kruger Effect, 128 years before it was named.
    0 0
  38. Ned "In another thread RSVP is questioning basic laboratory measurements of the spectral properties of gases that have been known since the 1850s" That is not what I am doing and you know that.
    0 0
  39. Actually, I don't know that. It sure seems like that's the impression you're trying to convey in this thread. If not, you might want to try to write more clearly. In particular, using repeated expressions like "According to AGW" and "I am being told that ..." when referring to the basic physics of infrared spectroscopy does not convey the impression of confidence in said spectroscopy. Most people, when writing about something they genuinely believe in, don't feel the need to add a continual stream of parenthetical qualifiers.
    0 0
  40. #101 chris at 09:17 AM on 25 July, 2010 We expect in a warming world that rainfall will decrease in the equatorial regions of the Earth You may expect that, but unfortunately reality does not seem to conform.
    0 0
  41. Berényi Péter at 09:14 AM on 27 July, 2010 "You may expect that, but unfortunately reality does not seem to conform." Careful Peter. One location does not define an entire longitudinal band. You really need to look at the paper I cited (Zhang et al., 2007; link in the post that you mined my sentence from). The 20th century has seen a decrease in rainfall in the equatorial regions from around 0 o longitude to 30 o N, and an increase in rainfall in the high latitudes. Pretty much as expected from models. X. Zhang et al. (2007) Detection of human influence on twentieth-century precipitation trends Nature 448, 461-465
    0 0
  42. not sure why I wrote "longitude" when I meant "latitude" in my post just above!
    0 0
  43. Berényi Péter writes: You may expect that, but unfortunately reality does not seem to conform. Can you explain, in words, what that figure shows and how precisely it contradicts the claim from chris's post? Thanks.
    0 0
  44. To Berenyi Peter,post 129. Many thanks for your clear explanation. And to Ned. I am not trolling or seeking to foist radical wacky new ideas on the world of physics. I am not a climate scientist or physicist, but a veterinarian, who has over the years picked up bits of information, some good and some bad.I want to rearrange and check that information. Anyway, the (Stef-Bol)constant is applicable at lower temperatures,and is widely used in the food industry.However,in the article I read, there was a comment to the effect that the computed temperature or heat given off by staightforward application of the formula would be higher than encountered in practice.So an arbitrary factor in the form of "emissivity" was applied. As this,as far as I am aware,is derived empirically, would I be right in deducing that this factor is a combination of actual emissivity(yet to be explained)and a convenient"fudge factor"? If there is a fudge factor,doesn't that point to something "not quite right"? I have attempted to get information on the application of the constant and the law, at low temperatures, but find that I have to pay for the information, which as a taxpayer rankles somewhat. Once again,thanks to Berenyi Peter for his positive response to my post, which perhaps should have taken the form of a question, rather than an assertion.
    0 0
  45. Ah. AWoL, that clarifies things a lot. In your previous comment you wrote The constant is a theoretical concept and simply,in it's present form does not match the real world which (while perhaps not intended that way) would be "fighting words" to anyone with a background in the physics of radiation. If I understand you rightly, though, you're actually asking about the relationship between emissivity and radiant exitance. For a blackbody, the thermal radiant flux emitted per unit area (M, in watts per square meter) is given by M = sigma * T^4 meaning that it's purely a function of the temperature of the blackbody (in Kelvins) and the Stefan-Boltzmann constant (5.6697 * 10^(-8) W m-2 K-4). In the real world, nothing is a blackbody, though some materials (e.g., water) are pretty darn close. Thus, we introduce the concept of a material's emissivity (the ratio of its radiant exitance to the theoretical radiant exitance of a blackbody at the same temperature): M = epsilon * sigma * T^4 If an object has uniform emissivity across a wide range of wavelengths (again, water makes a good example) we call it a gray body. Some material types have emissivities that are dependent on wavelength (quartz, for example), which makes them a bit more complicated to deal with. Emissivity isn't really a "fudge factor" any more than the "color" of an object is a "fudge factor". In fact, color (spectral reflectance) is a very good analogy for spectral emissivity. There is nothing particularly problematic about using the Stefan-Boltzmann law at typical earth surface temperatures. You can measure emissivity of objects very easily (actually, you can probably find tables with typical emissivity values on the web). So I'm really not sure what exactly prompted your comment up here. To anyone who is used to doing calculations of electromagnetic radiation fluxes it just seems wildly over-the-top. Actually, that comment reads a bit like someone claiming that the field of ballistics is garbage because it's based on Newton's inverse square law, which is purely theoretical and has to be modified empirically to account for air resistance. You write that you "attempted to get information on the application of the constant and the law, at low temperatures, but find that I have to pay for the information, which as a taxpayer rankles somewhat." That also seems kind of strange, since the application of the S-B law at normal earth temperatures is not at all obscure; it's covered in lots of textbooks. If there's some particular very specialized paper that you are looking for, would you mind telling us what it is? (I'm just curious, as it would help understand where you're coming from). I would gently suggest that one of the responsibilities of being a skeptic is appropriately modulating one's skepticism. The three comments here, here, and here might be cases where more discretion would have been in order.
    0 0
  46. #141 chris at 09:38 AM on 27 July, 2010 Careful Peter. One location does not define an entire longitudinal band I know. AGW always happens elsewhere, preferably at locations with the poorest data coverage :) Anyway, according to Zhang at al. precipitation is only supposed to decrease north of the equator, while Rio Negro is located right on it. So let's check another location. Hilo, Hawaii (General Lyman field, 19.70 N, 155.10 W) is the only station in GHCN v2 between the equator and 20 N with a reasonably long uninterrupted precipitation record (1943-2009). You can see the trend, can't you?
    0 0
  47. You can see the trend, can't you? Precipitation is highly variable, so it might be helpful to look at the entire 0-20 N region, rather than individual points. From New et al. (2001): The x-axis runs from 1900 to 2000. Note the long-term decline starting in the 1960s.
    0 0
  48. #147 Ned at 22:46 PM on 27 July, 2010 it might be helpful to look at the entire 0-20 N region, rather than individual points Definitely. Provided of course claims hard to verify and based on scant data are preferred to easy and well documented ones. It is Colaba Woods, Mumbai, India (18.9 N, 72.8 E).
    0 0
  49. Provided of course claims hard to verify and based on scant data are preferred to easy and well documented ones. That would be a reasonable assessment of my comment ... Provided of course that illogical and unfriendly interpretations are preferred to simple and straightforward ones! :-)
    0 0
  50. #136 Berényi Péter at 02:02 AM on 27 July, 2010 >> My point is that the writing on here seems very technical and if I may say so, not very persuasive. I understand it's a science blog but it is also a blog that is trying to persuade deniers that climate change is real. Being better at understanding what arguments (supported by science) are more effective at persuading people is "political" but not in the way that the comments policy prohibits. And unless "authenticity" means discussing only technical issues with no hope of convincing anyone of anything, I don't think coming up with focused arguments that better present the science and address the underlying concerns of the deniers would lack authenticity.
    0 0

Prev  1  2  3  4  Next

You need to be logged in to post a comment. Login via the left margin or if you're new, register here.



The Consensus Project Website

THE ESCALATOR

(free to republish)


© Copyright 2021 John Cook
Home | Links | Translations | About Us | Privacy | Contact Us