Extract from Steve Koonin's climate science book “Unsettled”. My personal view is: The Science is almost settled on the changing Sun and Sun-Earth relationship as the cause of almost all climate change; with the greenhouse gas effect being, essentially, fake science.
WHO BROKE “THE SCIENCE” AND WHY, Steve Koonin
Chapter 10, of “Unsettled”, by Steve Koonin, 2021.
If crucial parts of the science really are unsettled, as we’ve seen over the past chapters, why is the narrative of The Science so different? Can it really be that the multiplicity of stakeholders in climate matters—scientists, scientific institutions, activists and NGOs, the media, politicians—are all contributing to misinformation in the service of persuasion? And why has The Science gained such prominence over science?
Observing this scene over the years, I’ve given a lot of thought to how the communication of climate science works. I’m no expert on human behavior, but I have seen this process up close, and my direct experiences, along with some universal truths about humans, suggest not some secret cabal, but rather a self-reinforcing alignment of perspectives and interests. Let’s look at the most important players in turn.
THE MEDIA
When I moved to the UK in 2004, I naturally began reading the British newspapers. I was struck by how much more international coverage there was than in the US, no doubt because the smaller UK necessarily has more foreign interactions, as well as ties to the rest of Europe and historical relationships with Commonwealth countries once part of the British Empire. And of course, soccer—that is, football—got many more column inches. But what surprised me most wasn’t only a matter of content, but tone. The British papers were often overtly partisan, not just in their editorials, but also in their reporting. Although I had read widely among US national newspapers, including the New York Times, the Wall Street Journal, and the Washington Post, it was a revelation to see the stark differences in what was covered, and how it was covered, among the UK’s Guardian, the (London) Times, the Telegraph, and the Financial Times.
In the years since, US media outlets have developed more explicit and more differentiated points of view themselves, and those have likewise seeped from their editorial pieces into their reporting. Most notably, as the age of the internet advanced, headlines became more provocative to encourage clicks—even when the article itself didn’t support the provocation. Today, the shift toward the alarming—and shareable—has traveled well beyond the headlines. That’s especially true in climate and energy matters.
Whatever its noble intentions, news is ultimately a business, one that in this digital era increasingly depends upon eyeballs in the form of clicks and shares. Reporting on the scientific reality that there’s been hardly any long-term change in extreme weather doesn’t fit the ethos of If it bleeds it leads. On the other hand, there is always an extreme weather story somewhere in the world to support a sensational headline.
Changes in staffing also contribute to the media miscommunication of the science. Many newsrooms are shrinking, and serious in-depth reporting is becoming less common. Many people reporting on climate don’t have a background in science. This is a particular problem because, as we’ve seen, the assessment reports themselves can be misleading, especially to non-experts. Science stories are almost always stories of nuance; they require time and research. Unfortunately, the pace of the news cycle has only become more frantic, and reporters and editors have less time than ever. The diversity and ubiquity of modern media have increased the demand for fresh “content” and the competition to be the first to post a story. And as with scientists, a professional code that calls for lack of bias doesn’t mean none creeps in.
As I interact with journalists, I realize that, for some, “climate change” has become a cause and a mission—to save the world from destruction by humans—so that packing alarm into whatever the story is becomes the “right” thing to do, even an obligation. This has been compounded by the rise of a new job category: “climate reporters.” Their mission is largely predetermined; if they don’t have a narrative of doom to report, they won’t get into the paper (whether digital or print) or on the air.
Here’s an example. A recent front-page story in the Washington Post reported that the Biden administration’s climate policy would aim “to rapidly shrink the nation’s carbon emissions,” explaining that “a warming planet has made the issue increasingly hard to ignore, as the litany of climate-related catastrophes has grown with each passing year.”1
Of course, as you have already read, the data does not at all support that “climate-related catastrophes” are growing “with each passing year.” There’s much factual reporting in the full-page story that follows about plans for the new administration. But without those initial alarm bells, would the story have made it to the front page?
In short, the general lack of knowledge of what the science actually says, the drama of extreme weather events and their heart-rending impact on people, and pressures within the industry all work against balanced coverage in the popular media.
POLITICIANS
Politicians win elections by arousing passion and commitment from voters—by motivating and persuading. This is not new. H. L. Mencken’s 1918 book In Defense of Women noted:
The whole aim of practical politics is to keep the populace alarmed (and hence clamorous to be led to safety) by menacing it with an endless series of hobgoblins, most of them imaginary.2
The threat of climate catastrophe—whether storms, droughts, rising seas, failed crops, or economic collapse—resonates with everyone. And this threat can be portrayed as both urgent (by invoking a recent deadly weather event, for instance) and yet distant enough so that a politician’s dire predictions will be tested only decades after they’ve left office. Unfortunately, while climate science and associated energy issues are complicated, complexity and nuance don’t lend themselves at all well to political messaging. So the science is jettisoned in favor of The Science, and “simplified” for use in the political arena, which allows the required actions to be portrayed simply as well—just eliminate fossil fuels to save the planet.
Of course, this isn’t a climate-specific problem, and the electorate— which abhors a gray area—bears part of the blame. It’s hard to rally the base with uncertainty. There would surely be less support for, say, promoting renewable energy sources if they were more realistically portrayed as a possible way to mitigate a possible future problem instead of an essential solution to an imminent crisis. And uncertainty can be a political weapon. Politicians on the right who deny even the basics that science has settled— that human influences have played a role in warming the globe—are not above exploiting climate science uncertainties, offering them as “proof” that the climate isn’t changing after all.
Politicians on the left find it inconvenient to discuss scientific uncertainties or the magnitude of the challenge in reducing human influences. Instead, they declare the science settled and label anyone who questions that conclusion “a denier,” lumping conscientious scientists advocating for less persuasion and more research in with those openly hostile to science itself.
Some politicians have gone far beyond name-calling, brazenly attempting to undermine the scientific process. Two billionaire politicians, Michael Bloomberg and Tom Steyer, whose goal was “making the climate threat feel real, immediate, and potentially devastating to the business world,” conspired with some scientists and others to produce a series of reports mischaracterizing the extreme emissions scenario RCP8.5 as “business as usual” (that is, a world without further efforts to rein in emissions).3, 4 The reports were accompanied by a sophisticated campaign to infuse that notion into scientific conferences and journals.5 Those who seek to corrupt the scientific process in that way are playing the same game as the anti- science crowd they loudly decry. Fortunately, the deception is now being called out in leading scientific journals.6,7
Finally, it is standard practice to suggest that many of the politicians on the right who promulgate the idea of a “climate change hoax” are influenced by ties to industries negatively affected by restrictive environmental regulation. Alas, as the alternative energy industry grows, there is financial incentive for politicians to hype climate catastrophe as well. Science should not be partisan, but climate science’s intersection with energy policy and politics all but guaranteed that it would become so.
SCIENTIFIC INSTITUTIONS
Trust in scientific institutions underpins our ability—and the ability of the media and politicians as well—to trust what is presented to us as The Science. Yet when it comes to climate, those institutions frequently seem more concerned with making the science fit a narrative than with ensuring the narrative fits the science. We’ve already seen that the institutions that prepare the official assessment reports have a communication problem, often summarizing or describing the data in ways that are actively misleading. In the next chapter, we’ll delve a bit further into how this happens; I won’t belabor the point here.
Other scientific institutions, or their leaders, have also been overwilling to persuade rather than inform. The National Academies of Sciences, Engineering, and Medicine (NASEM) is a private, nonprofit institution chartered by the US Congress in 1863 to advise the nation. To quote from their website:
The National Academies of Sciences, Engineering, and Medicine are the nation’s pre-eminent source of high-quality, objective advice on science, engineering, and health matters.8
The Academies provide that advice largely through written reports sponsored by federal agencies. Some two hundred reports are published each year, dealing with a great range of topics in science, engineering, medicine, and the societal issues associated with them.9
Academies reports undergo an extensive authoring and review process. I know that process well, having led two Academies studies and reviewed the reports of several others, along with for six years overseeing all the Academies’ report activities in Engineering and the Physical Sciences (including several in Energy, but none in Climate Science). This process does indeed result in reports that are almost always objective and of the highest quality. Unfortunately, as we’ve seen, their reviews of the National Climate Assessments (they don’t write the assessments themselves) in 2014 and 2017/18 didn’t quite meet that standard.
On June 28, 2019, the presidents of the National Academies of Science, Engineering, and Medicine issued a statement affirming “the Scientific Evidence of Climate Change.” The sole paragraph dealing with the science itself read:
Scientists have known for some time, from multiple lines of evidence, that humans are changing Earth’s climate, primarily through greenhouse gas emissions. The evidence on the impacts of climate change is also clear and growing. The atmosphere and the Earth’s oceans are warming, the magnitude and frequency of certain extreme events are increasing, and sea level is rising along our coasts.10
Even given the need for brevity, this is a misleadingly incomplete and imprecise accounting of the state of climate science. It conflates human-caused warming with the changing climate in general, erroneously invokes “certain extreme events” while omitting the fact that most types (including those that pop most readily to mind when one reads the phrase “extreme events,” like hurricanes) show no significant trend at all. And it states that “sea level is rising” in a way that not only suggests that this, too, is solely attributable to human-caused warming, but elides the fact that the rise is nothing new.
I’m quite sure that this personal statement issued by the presidents in a news release was not reviewed by the usual Academies procedures; if it had been, its deficiencies would have been corrected. The statement therefore carries the weight of the Academies’ name without being subject to its customary rigor. Ironically, the statement goes on to say the Academies “need to more clearly communicate what we know.” Which in this case they didn’t.
When communication of climate science is corrupted like this, it undermines the confidence people have in what the scientific establishment says about other crucial societal issues (COVID-19 being the outstanding recent example). As Philip Handler, a prior president of the National Academy of Sciences, wrote in the 1980 editorial I mentioned in the Introduction:
It is time to return to the ethics and norms of science so that the political process may go on with greater confidence. The public may wonder why we do not already know that which appears vital to decision—but science will retain its place in public esteem only if we steadfastly admit the magnitude of our uncertainties and then assert the need for further research. And we shall lose that place if we dissemble or if we argue as if all necessary information and understanding were in hand. Scientists best serve public policy by living within the ethics of science, not those of politics.11
SCIENTISTS
This book’s introduction described Stephen Schneider’s false choice between being effective and being honest. But there are other factors that encourage climate researchers’ monolithic portrayal of the science as settled, however vigorous their internal debates might be. Feynman closes his Cargo Cult speech by wishing the Caltech graduates
the good luck to be somewhere where you are free to maintain the kind of integrity I have described, and where you do not feel forced by a need to maintain your position in the organization, or financial support, or so on, to lose your integrity.
I know from experience that such institutional pressures are real; whether you’re working for the government, a corporation, or an NGO, there is a message to be adhered to. For academics, there is pressure to generate press and to secure funding through grants. There’s also the matter of promotion and tenure. And there is peer pressure: more than a few climate contrarians have suffered public opprobrium and diminished career prospects for publicizing data that doesn’t support the “broken climate” meme.
Carl Wunsch, a prominent oceanographer from MIT who has long urged scientists to be realistic in their portrayal of the science,12 has written about the pressures on climate scientists to produce splashy results:
The central problem of climate science is to ask what you do and say when your data are, by almost any standard, inadequate? If I spend three years analyzing my data, and the only defensible inference is that “the data are inadequate to answer the question,” how do you publish? How do you get your grant renewed? A common answer is to distort the calculation of the uncertainty, or ignore it all together, and proclaim an exciting story that the New York Times will pick up.
A lot of this is somewhat like what goes on in the medical business: Small, poorly controlled studies are used to proclaim the efficacy of some new drug or treatment. How many such stories have been withdrawn years later when enough adequate data became available?13
Scientists not involved with climate research are also to be faulted. While they’re in a unique position to evaluate climate science’s claims, they’re prone to a phenomenon I call “climate simple.” The phrase “blood simple,” first used by Dashiell Hammett in his 1929 novel Red Harvest, describes the deranged mindset of people after a prolonged immersion in violent situations; “climate simple” is an analogous ailment, in which otherwise rigorous and analytical scientists abandon their critical faculties when discussing climate and energy issues. For example, the diagnosis was climate simple when one of my senior scientific colleagues asked me to stop “the distraction” of pointing out inconvenient sections of an IPCC report. This was an eyes-shut-fingers-in-the-ears position I’ve never heard in any other scientific discussion.
What causes climate simple? Perhaps it is a lack of knowledge of the subject, or fear of speaking out, particularly against scientific peers. Or perhaps it is simple conviction born more of faith in the proclaimed consensus than of the evidence presented.
Leo Tolstoy’s 1894 philosophical treatise The Kingdom of God Is Within You contains the following thought:
The most difficult subjects can be explained to the most slow-witted man if he has not formed any idea of them already; but the simplest thing cannot be made clear to the most intelligent man if he is firmly persuaded that he knows already, without a shadow of doubt, what is laid before him.14
Whatever its cause, climate simple is a problem. Major changes in society are being advocated and trillions will be spent, all based on the findings of climate science. That science should be open to intense scrutiny and questioning, and scientists should approach it with their usual critical objectivity. And they shouldn’t have to be afraid when they do.
ACTIVISTS AND NONGOVERNMENTAL ORGANIZATIONS (NGOS)
My inbox fills with fundraising appeals from such organizations as 350.org, the Union of Concerned Scientists, and the Natural Resources Defense Council. If you believe there is a “climate emergency,” have built an organization on that premise, and rely upon your donors’ continuing commitment to the cause, projecting urgency is crucial. Hence statements like “The climate crisis is immense—we must be daring and courageous in response” (from the 350.org website15) or “Climate change is one of the most devastating problems that humanity has ever faced—and the clock is running out” (from the UCS website16). It’s hardly in your best interest to tell your donors that the climate shows no sign of being broken or that projections of future disasters rely on models of dubious validity. The media tend to accord NGOs an authoritative stance. But these are also interest groups, with their own climate and energy agendas. And they are powerful political actors, who mobilize supporters, raise money, run campaigns, and wield political power. For many, the “climate crisis” is their entire raison d’etre. They also have to worry about being outflanked by more militant groups.
I have no problem with activism, and the efforts of NGOs have made the world better in countless ways. But distorting science to further a cause is inexcusable, particularly with the complicity of those scientists who serve on their advisory boards.
THE PUBLIC
Fear of extreme weather events is understandable, and concerns about changes in climate are as old as humanity. Short-term weather events (storms, floods, droughts) have stressed and challenged societies, while changes extending over decades induced mass migrations or even destroyed entire civilizations. For example, repeated crop failures devastated communities in the southwest United States during the twenty-five-year-long Great Drought about 750 years ago.17
The notion that our behavior might be causing such calamities is also as old as humanity—as is the hope that we might avoid the worst of climate disasters by changing our behavior. Leviticus 26:3–4 promises regular rain (very important in the Middle East) and its ensuing benefits in return for doing the right thing:
If ye walk in my statutes, and keep my commandments, and do them; Then I will give you rain in due season, and the land shall yield her increase, and the trees of the field shall yield their fruit.
We like to think public attitudes toward climate today are more discerning, but they still mostly involve unquestioning acceptance of wisdom handed down from on high. As around the world, most citizens in America are not scientists, and the educational system does not deliver much in the way of scientific literacy to the wider public. Most people do not have the ability to examine the science themselves, and they have neither time nor the inclination to do so. Many increasingly get their information from social media, where it is far too easy to promote misinformation or disinformation. And in my experience, people tend to believe—and trust—their chosen media in areas outside their expertise.
Michael Crichton, the bestselling author of The Andromeda Strain and Jurassic Park, lived near Caltech and was a prominent member of Pasadena’s extended intellectual community until his death in 2008. Crichton, who was a physician before he became a writer, was an outspoken advocate for scientific integrity, and he looked askance at the public presentation of climate science (his 2004 novel State of Fear deals with that subject). Crichton’s conversations with Caltech professor Murray Gell-Mann (the Nobel prize–winning physicist who was one of the first researchers to hypothesize quarks) led him to describe the “Gell-Mann Amnesia” effect:
You open the newspaper to an article on some subject you know well. In Murray’s case, physics. In mine, show business …
In any case, you read with exasperation or amusement the multiple errors in a story, and then turn the page to national or international affairs, and read as if the rest of the newspaper was somehow more accurate about Palestine than the baloney you just read. You turn the page, and forget what you know.18
It certainly doesn’t help that, at this point, even attempting a discussion of The Science is to enter a political minefield. When I tell people some of the things the assessment reports really say about climate, many immediately ask whether I was a Trump supporter. My reply is that I was not, and that, as a scientist, I have always supported truth.
As a scientist, I’m disappointed that so many individuals and organizations in the scientific community are demonstrably misrepresenting the science in an effort to persuade rather than inform. But you also should be concerned as a citizen. In a democracy, voters will ultimately decide how society responds to a changing climate. Major decisions made without full knowledge of what the science says (and doesn’t say) or, even worse, on the basis of misinformation, are much less likely to lead to positive outcomes. COVID-19 offered a sobering illustration of this, and it’s as true for climate and energy as it is for pandemics.
Notes
- Brady, Dennis and Juliet Eilperin. “In Confronting Climate Change, Biden Won’t Have a Day to Waste.” Washington Post. December 22, 2020. https://www.washingtonpost.com/politics/2020/12/22/biden-climate-change/.
- Mencken, H. L. In Defense of Women. Project Gutenberg. Last updated February 6, 2013. https://www.gutenberg.org/files/1270/1270-h/1270-h.htm.
- Helm, Burt. “Climate Change’s Bottom Line.” New York Times, January 31, 2015. https://www.nytimes.com/2015/02/01/business/energy-environment/climate-changes-bottom-line.html.
- The Risky Business Project. “Risky Business: The Economic Risks of Climate Change in the United States.” June 2014. http://riskybusiness.org/site/assets/uploads/2015/09/RiskyBusiness_Report_WEB_09_08_14.pdf.
- Pilke, Roger. “How Billionaires Tom Steyer and Michael Bloomberg Corrupted Climate Science.” Forbes, January 2, 2020. https://www.forbes.com/sites/rogerpielke/2020/01/02/how-billionaires-tom-steyer-and-michael-bloomberg-corrupted-climate-science.
- Hausfather, Zeke, and Glen P. Peters. “Emissions—the ‘business as usual’ story is misleading.” Nature, January 29, 2020. https://www.nature.com/articles/d41586-020-00177-3.
- Burgess, Matthew G., et al. Environmental Research Letters 16 (2020). https://doi.org/10.1088/1748-9326/abcdd2.
- “About Us: Who We Are.” The National Academies of Sciences, Engineering, and Medicine. Accessed December 1, 2020 https://www.nationalacademies.org/about.
- The National Academies of Sciences, Engineering, and Medicine. “Climate Change Publications.” The National Academies Press. Accessed December 1, 2020. https://www.nap.edu/.
- McNutt, Marcia, C. D. Mote Jr., Victor J. Dzau. “National Academies Presidents Affirm the Scientific Evidence of Climate Change.” The National Academies of Sciences, Engineering, and Medicine, June 18, 2019. http://www8.nationalacademies.org/onpinews/newsitem.aspx?RecordID=06182019.
- Handler, Philip. “Public Doubts About Science.” Science, June 6, 1980. https://science.sciencemag.org/content/208/4448/1093.
- Wunsch, Carl. “Swindled: Carl Wunsch Responds.” RealClimate, March 12, 2007. http://www.realclimate.org/index.php/archives/2007/03/swindled-carl-wunsch-responds/comment-page-3/.
- Revkin, Andrew C. “A Closer Look at Turbulent Oceans and Greenhouse Heating.” New York Times, August 26, 2014. https://dotearth.blogs.nytimes.com/2014/08/26/a-closer-look-at-turbulent-oceans-and-greenhouse-heating/.
- Tolstoy, Leo. 1894. The Kingdom of God Is Within You. Project Gutenberg, July 26, 2013. https://www.gutenberg.org/files/43302/43302-h/43302-h.htm.
- “About 350.Org.” 350.org. Accessed December 1, 2020. https://350.org/about/.
- “Climate Change.” Union of Concerned Scientists. Accessed December 1, 2020. https://www.ucsusa.org/climate.
- The Editors of Encyclopaedia Britannica. “Great Drought.” Encyclopædia Britannica, November 26, 2012. https://www.britannica.com/event/Great-Drought#ref=ref112984.
- Crichton, Michael. At the International Leadership Forum, La Jolla, CA, April 26, 2002. http://geer.tinho.net/crichton.why.speculate.txt.
You are close, but you have not explained how the required thermal energy actually gets into the surface or to the base of the nominal troposphere of Uranus where it's 320K - hotter than Earth's surface.
ReplyDeleteNikolov & Zeller came close, but they are wrong in assuming high pressure causes high temperature. Temperature and density gradients are formed by gravity. Pressure is a corollary. Robinson and Catling may well get a rough relationship between pressure and temperature, but the physics tells us the temperature gradient is related to the quotient g/Cp reduced a little by inter-molecular radiation. I don’t see these guys explaining the necessary energy flows – as I have done.
Why don’t you save your time and spend an hour reading my book, and you’ll then understand energy flows on Venus and probably agree with the two physicists who wrote positive 5 star reviews of the book. Email me a postal address to its.not.co2@gmail.com and I’ll post a free copy.
Conduction between sun warmed gas molecules ?
DeleteWhat else do you suggest ?
I suggest spam binning Doug's 140 personas by filtering on "my book"
DeleteJust as a side note,THE James Clerk Maxwell died in 1879, with significant publications in the 1860's and 1870's. So perhaps you are referring to a different Maxwell who was published in 1888.
DeleteI am definitely referring to the great physicist James Clerk Maxwell, and page 331 quoted above in his book Theory of Heat [this is apparently the 10th edition published in 1902 "with additions and corrections by Lord Rayleigh"] in entirely is available here:
Deletehttps://archive.org/stream/theoryofheat00maxwrich#page/n349/mode/2up
But here is a pdf of the entire 3rd edition which was published in 1872
http://www3.nd.edu/~powers/ame.20231/maxwell1872.pdf
I'm not sure when the 1st edition was published, but if you find out, pls let me know. In the meantime I'll change the date to the third edition 1872 in the post.
Thanks for pointing out.
Pretty much as described here:
ReplyDeletehttp://www.newclimatemodel.com/greenhouse-confusion-resolved/
back in 2008
but with added maths.
Your "hydrostatic equilibrium" is identical to thermodynamic equilibrium and that is fundamentally important to understand if you really want to understand the "heat creep" process which is a corollary of the Second Law of Thermodynamics. That non-radiative heat transfer mechanism downwards is what obviates any need for assumed (though impossible) heat transfer from a colder troposphere to a warmer surface.
ReplyDeleteDownwards ?
DeleteDon't you mean upwards via conduction from the sun warmed surface ?
Mr Wilde,
DeleteYou continue to imply, after all these years, that the surface is always warmer and thus, heats the air directly above, via conduction and that that is how the atmosphere is warmed. Which incidentally, also happens to be a major pillar of the debunked "GHE" hypothesis.
Yet the radiosonde data clearly shows that over most of the Earths solid surface, most of the year round, the ground is actually cooler than the air above it. While the oceans covering the remaining 70% of the Earths non-gaseous surface cannot conduct heat the air above because of evaporative cooling.
It's about time you changed the record mate!
W R Pratt
W R Pratt
DeleteWhere the sun is shining the surface is warmer than the air and where it is not shining the air is warmer than the surface. That is on average and through the system as a whole, not necessarily locally or regionally due to winds.
The energy held by the air at any given time was initially obtained by conduction from the solid surfaces.
Water is different. Solar energy enters past the evaporating layer and then is distributed between water molecules by conduction. Evaporation results but does not fully negate that initial accumulation of conducted energy due to the weight of the atmosphere pressing down on the surface.
So, sadly, you are wrong.
Stephen WildeNovember 25, 2014 at 2:05 AM
Delete"Where the sun is shining the surface is warmer than the air and where it is not shining the air is warmer than the surface."
Wrong! This is entirely dependant on the surface material. Most of the Earths solid surface that has strong enough incident sunlight to heat the ground above the temperature of the air, is also covered in vegetation. Vegetation does not heat the air by conduction, in fact it cools it. This can be seen in the radiosonde data. Regions of the Earths surface which are not covered in vegetation and do get warm enough to potentially heat the air above are only localised and therefore cannot possibly be responsible for the atmospheres diurnal 2pm max-4am min, temperature cycle.
"That is on average and through the system as a whole, not necessarily locally or regionally due to winds.
The energy held by the air at any given time was initially obtained by conduction from the solid surfaces."
Wrong again Mr Wilde, unless of course you believe wind travels at light speed!
If local conditions are stable, the warmest part of the day, the diurnal max, is ALWAYS at 2 pm, regardless of surface material. Again, empirical observation disproves your Wilde assertions. This kind of empirical observation is evidence that incident sunlight heats both the surface and the air.
"Water is different. Solar energy enters past the evaporating layer and then is distributed between water molecules by conduction. Evaporation results but does not fully negate that initial accumulation of conducted energy due to the weight of the atmosphere pressing down on the surface."
Well, lets see now, if what you say here was correct, then the temperature of the near surface atmosphere would need to always closely track the temperature of the ocean below. I have yet to see any data to support that Wilde assertion. Therefore the ocean is not able to conduct any significant heat to the atmosphere directly above it and again, if it could it would be a purely localised phenomena which cannot account for the diurnal atmospheric temperature cycle.
Perhaps you have such data to prove me wrong on that. I look forward to seeing that from you.
W R Pratt
The temperature of the near surface atmosphere does indeed closely track the temperature of the ocean below. Meteorologists rely on that for predicting temperatures over land when air flows off the nearby ocean.
DeleteThe rest of your post is too confused to merit a response.
You have no data the Stephan?
DeleteW R Prat
A very fine post; thanks much. It was well written and easy to follow. I only wish all the luke-warmers would read it with an open mind.
ReplyDeleteSo this could explain why the tropospheric hot spot is missing. Instead of warming, the energy that would have formed the hotspot becomes Gravitational Potential Energy?
ReplyDeleteYes absolutely, I just added the explanation of that and more at the end of the post
DeleteIndeed, and further, ALL energy that goes into lifting the atmosphere against gravity but which is not radiated to space from within the atmosphere goes to gravitational potential energy.
DeleteThen it returns to kinetic energy during the inevitable descent and THAT is what raises surface temperature by 33C above the S-B prediction.
It is all about mass, gravity and insolation.
It is variations in the rate of convection that regulates the flow of kinetic energy back to the surface from gravitational potential energy higher up which negates the thermal effect of radiative gases.
Convection controls the balance between radiation and conduction in order to maintain system stability.
Response by Climatepete
ReplyDeleteThe article contains the seeds of its own destruction because it says "It is well-known that CO2 and ozone are the primary cooling agents of the stratosphere up to the thermosphere....".
For a significant part of the infra-red spectrum emitted by the earth back into space it is the temperature of the stratosphere which determines the power radiated into space by the top of the atmosphere. However, the incoming solar radiation is visible light radiation and CO2 and ozone are transparent to those frequencies.
Now think about it - say you have an atmosphere with no CO2 and you add some CO2. From the "primary cooling agents" comment above the temperature of the stratosphere goes down, and therefore so does the radiation emitted back into space from the stratosphere and hence the radiation emitted back into space from the top of the atmosphere also goes down. The radiation from sunlight reflected directly back into space doesn't change. Why should it? All we have done is added a miniscule quantity of CO2 which is transparent to visible light.
But the incoming radiation doesn't reduce because CO2 has no effect on this.
The radiative forcing by definition is the difference between solar radiation received and the radiation emitted back into space at the top of the atmosphere. Adding CO2 makes no different to the incoming or reflected sunlight, but has reduced the outgoing infra-red radiation. Therefore, by the law of conservation of energy it has increased the radiative forcing and the temperature of the surface has to go up.
In other words the phrase "It is well-known that CO2 and ozone are the primary cooling agents of the stratosphere up to the thermosphere...." carries with it an implication that adding CO2 must somehow have increased radiative forcing and therefore surface temperatures. We don't even need to postulate a mechanism to know this to be true.
Regards,
Climatepete
"the temperature of the stratosphere goes down, and therefore so does the radiation emitted back into space from the stratosphere and hence the radiation emitted back into space from the top of the atmosphere also goes down." is backwards.
DeleteIncreased CO2 increases IR radiative surface area of the troposphere through thermosphere, but we'll just talk about the stratosphere. CO2 cools the stratosphere both by radiating the heat received primarily from convection from the surface through the troposphere, but also direct IR from the surface through the atmospheric window.
I'm sorry, but a cooling agent that enhances radiative losses to space can only cool, not warm, any part of the atmosphere.
Your understanding is flawed.
DeleteAssume for the sake of clarity a black-body infra-red spectrum of power emitted from the ground which is dependent on the temperature at every wavelength. Then introduce the CO2 into the atmosphere.
In case you didn't know, the atmosphere (with CO2) is opaque to 10 micron radiation emitted directly from the ground - i.e. you cannot image tanks with hot gun barrels and other stuff from space using the 10 micron band. The 10 micron radiation you see from space comes mainly from the stratosphere so anything from the ground has been absorbed and re-emitted many times as seen from space.
Now if a molecule of anything is in thermodynamic equilibrium with the gas around it then its emissions CANNOT BE MORE at any wavelength than the black-body spectrum for the given temperature, because if they were you could use the imbalance to generate power from evenly distributed heat, which cannot happen by the second law of thermodynamics (e.g. a solar cell sensitive to that wavelength would generate power because it would receive more heat at that wavelength than it naturally emitted)
Therefore, if CO2 cools the stratosphere (which you say it does), and if the direct 10 micron radiation comes from the stratosphere (which it does), then the black-body radiation emitted from the stratosphere must be weaker at all wavelengths purely because the temperature is lower. Sure some radiation still gets through the stratosphere from below, but the power is the same as it was with the original stratospheric temperature before CO2, not higher. Any bands where the radiation comes from the stratosphere have to have a lower power emitted because of the lowering of temperature.
Doesn't matter whether the temperature of the stratosphere is because of convection or because of other effects - if it is lower then at certain bands the emissions will be lower with CO2 that without CO2, which means that overall the radiation at the top of the atmosphere emitted back to space is lower as a direct consequence of the lower stratospheric temperature.
Thus your phrase "a cooling agent that enhances radiative losses to space" is directly forbidden by the laws of thermodynamics.
Note that convection cannot itself carry heat beyond the top of the atmosphere because no molecules are actually lost into space as they don't have the energy to escape.
Regards,
Climatepete
CO2 peak absorption/emission is at 15u, not 10u. 10u is part of the "atmospheric window" of direct emission to space from the surface (although O3 absorbs/emits nearby)
Deletehttp://www.junksciencearchive.com/Greenhouse/2-03.jpg
By Wien's displacement law, 15u emission is equivalent to a BB temperature of -80C. No matter where CO2 is located in the troposphere/stratosphere/etc or the concentration of CO2, or the temperature of the surrounding air, CO2 still absorbs/emits at 15u/-80C, which is colder than any part of the atmosphere.
There is no convection in the stratosphere. Convection stops at P=0.1 bar tropopause as shown by R&C above.
Even the most ardent warmists admit CO2 cools the stratosphere, although they don't agree on why.
http://hockeyschtick.blogspot.com/2014/08/why-does-co2-cool-stratosphere-warm.html
Here's an illustration of the "atmospheric window" from the surface, showing between 8-12 microns [near-IR with higher energy/frequency] most of IR radiation travels directly from the surface to space without running into any GHGs [except O3 a bit], a large negative radiative forcing. Earth's peak IR emission is at 10-11 microns, where most of it isn't impeded by GHGs at all.
Deletehttp://scienceofdoom.files.wordpress.com/2010/04/longwave-downward-radiation-surface-evans.png
climatepete said:
Delete"say you have an atmosphere with no CO2 and you add some CO2. From the "primary cooling agents" comment above the temperature of the stratosphere goes down, and therefore so does the radiation emitted back into space from the stratosphere and hence the radiation emitted back into space from the top of the atmosphere also goes down."
Radiation to space from within the atmosphere increases from the introduction of GHGs but the amount of energy returned to the surface in adiabatic descent declines so that less energy is then radiated directly to space from the surface leaving the net radiative exchange with space unaffected.
Meanwhile the surface temperature is unaffected too because the reduction in energy returning to the surface in adiabatic descent is offset by the increased density of the air at the surface which can then conduct more of the solar energy passing through.
Leakage from the adiabatic cycle of ascent and descent (caused by the presence of radiative gases) simply results in a less high atmosphere (less work is done against gravity due to the leakage) and so surface density becomes higher at the same atmospheric pressure.
Gas Laws apply at all times.
MS, very nice, seems complete and it matches several emperical results regarding IR opaque layers "blocking" heat flow, ie the R. W. Wood experiment from 100 years ago.
ReplyDeleteDid you know that R. W. Wood disproved the exsistence of "N - Rays" as well ?
Maybe there needs to be some "blanket" re-thinking of popular unproven hypothesis now
Cheers, KevinK
Ah, physicist RW Wood, the world's first CAGW skeptic and prime example of why the best scientists are skeptics of the "overwhelming scientific consensus"
DeleteBlanket/greenhouse analogy to gases free to convect is just plain dumb
Stephen and Roger:
ReplyDeleteYes conduction, diffusion, convection (which includes diffusion) from cold to warm in accord with the process described in statements of the Second Law of Thermodynamics. The explanation has been published in March this year in two chapters (complete with graphics) you know where. After all, on Uranus the only source of new thermal energy is mostly in the absorbing methane layer near TOA where it's colder than 60K. But the base of the nominal troposphere of Uranus is 320K. You need to explain energy flows my friends, and your explanation should be applicable universally - for example, throughout the Solar System and no doubt beyond.
Sorry, but I don't get this approach at all. Here is the premise for this analysis:
ReplyDelete"We are determining the temperature gradient within the mass of the atmosphere and the equilibrium temperature is thus at the center of mass. The "effective radiating level" or ERL of planetary atmospheres is located at the approximate center of mass of the atmosphere where the temperature is equal to the equilibrium temperature with the Sun. The equilibrium temperature of Earth with the Sun is commonly assumed to be 255K or -18C as calculated here. As a rough approximation, this height is where the pressure is ~50% of the surface pressure. It is also located at the approximate half-point of the troposphere temperature profile set by the adiabatic lapse rate, since to conserve energy in the troposphere, the increase in temperature from the ERL to the surface is offset by the temperature decrease from the ERL to the tropopause."
But all this only works (at least to a fair approximation) with the Earth. It doesn't work at all with the other planets, notably Venus and Mars.
Check it out for yourselves. The fundamental premise behind this approach thus fails.
No it absolutely does work perfectly for Venus as I tweeted today:
Deletehttps://twitter.com/search?q=90bar%2F2&src=typd
Atmosphere on Mars is too thin to sustain much convection, that's why the convection > radiative forcing principle only applies to the planets with thick atmospheres shown in Fig 1 above.
For Venus, surface P=90 bar
Delete90 bar/2 = 45bar
45 bar is at a height of ~20km per Magellan mission:
https://pbs.twimg.com/media/B3PH_6ICIAAFJEW.jpg
Venus equilibrium temperature with the Sun = 260C
Venus lapse rate =10C/km
260C+10C/km*20km = 460C = Ts
Uhm, no. Venus lapse rate: ~8 K/km. 46 bar is at ~12 km. Surface temp: 735K. Temp at 12 km: [735 - (12*8) =] 639K. Venus radiating temperature in space: 184K (Bond albedo 0.9) or 232K (albedo 0.75). Former at 80+ km (0.003 bar), latter at 65 km (0.1 bar).
Deletehttp://www.datasync.com/~rsf1/vel/1918-3b.gif
https://pbs.twimg.com/media/B3PH_6ICIAAFJEW.jpg
There's plenty of convection on Mars. The ERL is about 2.5 K/km. The surface temp is about the same as the planetary effective emission temperature to space: 210K.
There is no connection.
Mars:
DeleteAccording to R&C: "Mars’ low surface pressure of
∼0.006 bar means that it does not fall within our scope of examining
commonalities in thick atmospheres and so Mars is not plotted
in Fig. 3a."
Venus:
You're right I made an error on Te of Venus and so will begin anew to establish whether the CoM concept applies to Venus, and to Titan...
"Venus does not have a well-developed tropopause temperature
minimum in the global average because it lacks a significant
stratospheric inversion, which is consistent with our tropopause
theory. However, Venus is marginal (Fig. 3a) and, in fact, possesses
a distinct tropopause temperature minimum at ∼0.1 bar in its mid
to high latitudes17, and so conforms to the ∼0.1 bar rule when a
minimum is seen (see Supplementary Information). The reason
for the latitudinal variations in tropopause sharpness is unknown
but may be a modulation of the radiative–convective mean state
by a Hadley-like meridional circulation above the cloud tops18.
The interpretation is complicated by the presence of unknown
absorbers at 0.2–0.5 µm (ref. 19)."
Venus is a special case and very odd planet in comparison to all the others with thick atmospheres as R&C and others have discussed, including opaque TOA, and convection/lapse rate extends way beyond 0.1 bar up to 0.001 bar as shown by R&C, unlike any of the other planets which were analyzed by R&C, so I'm going to think about this some more regarding center of mass from a thermodynamic standpoint on Venus, and maybe ask Claes Johnson about the CoM concept with respect to the special case of Venus and wrt Earth.
Let me know if you have any other suggestions, but just because Mars doesn't apply and Venus could be a special case, no doubt pressure determines the Venus temperature profile, not radiative forcing, so still doesn't support the radiative theory of the GHE vs. the mass/pressure theory of the GHE.
I updated the post adding data for Titan, the closest Earth analog with a thick atmosphere, and it appears the CoM assumption is applicable to Titan. Agreed?
DeleteI believe the Mars discussion founders on empirical observations. Mars is subject to "dust devils" and thus, convection is definitely actively cooling the surface, regardless of the density of the atmosphere. Evidently the same principles applied in the article pertain to Mars.
DeleteClose, however the earth has *two* photospheres, the solid surface and the cloud tops. The radiative equilibruim height for the equator are the cloudtops, The equilibrium height for the desert areas is the surface. 80% of heat is radiated from the desert surface of the Sahara and australia. Look at infrared images of Meteosat to get the picture.
ReplyDeleteThe ERL is (on global average) the height at which T ≈ 255K = equilibrium temperature with the Sun. However, T is a function of P, and radiance/emission spectra a function of T, not the other way around as climatologists assume.
DeleteI think there is an error in Figure 1. The tic mark labelled 0.5 bar looks to me like 0.4 bar. There is a missing tic mark between that and 1 bar, so it looks right if you count down from 1 but wrong if you count up from 0.1. This messes up the perfect agreement with 255K, more like 260K or more.
ReplyDeleteYeah looks like R&C left off the tick mark for 1.0 and that's exactly what I did count back from what I thought was 1.0 but is apparently 0.9 instead. Thanks for pointing that out, but Fig 1 from R&C is very low resolution graph anyway to show all of the planets with thick atmospheres on a single graph.
DeleteNot to worry, the US Standard Atmosphere Calculator
http://www.digitaldutch.com/atmoscalc/
Shows at 5.1km the temperature is 255.0K and P=533 millibars = 0.53bar
Thus, almost precisely what I showed in the post:
P ≈ 0.5 bar and T = 255K at ≈ 5km.
As I keep saying, the 255K temperature is invalid because it is for an impossible situation in which there is no water vapour, but supposedly still exactly the same cloud cover reflecting 30% of solar radiation back to space. If you don't reduce (by 30%) the solar radiation to the surface of an Earth without GHG then you get about 278K, not the 255K which Hansen and Pierrehumbert et al claim then leads to 33 degrees of warming.
ReplyDeleteNote also that the altitude about which the temperature profile rotates as water vapour varies is only around 3.5Km to 4Km because we need the altitude where radiation to space from above equals that from below, including the surface. Even the centre of mass is lower than 5Km because of the density gradient which, by the way, also results from the process described in statements of the Second Law of Thermodynamics - in exactly the same way that the temperature gradient evolves as entropy approaches the maximum.
255K is confirmed by the radiosonde data.
DeleteW R Pratt
W R Pratt misses the point that the 255K figure supposedly relates to an imaginary Earth without water vapour or any greenhouse gases. Hence radiosonde data regarding the real Earth with clouds reflecting 30% of the solar radiation is not relevant. My whole point is that there would be no clouds in the absence of water vapour.
DeleteYet there in black and white in Pierrehumbert's book we see him multiplying the radiative flux by 0.7 which is deducting the 30% of solar radiation which would not need to be deducted because there would be no clouds. Take out the 0.7 and you get a more correct temperature of 278K for that imaginary dry rocky planet.
Is this a valid point? You bet it is. The IPCC clearly claims that the real Earth is 33 degrees hotter than the imaginary planet, whereas in fact it is less than 10 degrees hotter. And even that is very rough and it could be cooler because the 278K figure does not take into account the T^4 relationship. In fact, when water vapour increases from about 1% to 4% we get a few degrees of cooling easily observed in real world temperature data as in my published study in the book. The cooling is at least partly due to cloud cover that increases with increasing water vapour.
As I said Doug, 255K is confirmed by the radiosonde data. Regardless of your arguments to the contrary, 255K is observed by satellite and radiosonde data.
DeleteEmpirical evidence is what you are arguing against.
That is the point.
Radiation between a warmer surface and a cooler troposphere is cooling the surface. Only radiation from a hotter source can raise the temperature of a cooler target, and only to a maximum as per Stefan Boltzmann calculations. Even those calculations become irrelevant if that target does not meet the definition of a black or grey body that does not gain or lose thermal energy by non-radiative processes, only by radiation. But you can work out the maximum mean surface temperature that radiation could support, and, for 163W/m^2 of solar radiation reaching Earth's surface that mean temperature is around 35 degrees below freezing.
ReplyDeleteThe whole concept of "radiative forcing" has absolutely no basis in physics. Radiation from a cooler source can only slow that portion of the cooling of a warmer target which is itself by radiation. Radiation from a colder troposphere does not slow the rate of evaporative cooling or conduction across the surface/atmosphere interface. (See my March 2012 paper.) These non-radiative processes can and will accelerate to nullify the reduction in radiative cooling. In any event, one molecule of carbon dioxide in 2,500 other molecules has absolutely minuscule effect on the rate of radiative cooling of Earth's surface. It does not affect the maximum which must be explained by another process in a completely different paradigm that does indeed operate throughout the Universe.
Radiation from the cooler troposphere cannot be added to solar radiation and the total used in Stefan Boltzmann calculations. Even those calculations overstate the temperature because the surface is simultaneously losing energy from some of the solar radiation by non-radiative processes. You need to explain how the necessary thermal energy gets into the surfaces of Earth, Venus etc. And you need to do this in keeping with the laws of physics, as I have done successfully and in agreement with empirical data.
MS, my replies to Steven Wilde and Doug Cotton have gone missing.
ReplyDeleteW R Pratt
"I suggest spam binning Doug Cotton's 140 personas"
ReplyDeleteI highly recommend that as well. He’s an infiltrator, and pretends that heat conducts down from the top of the atmosphere or some stupid thing, without showing the math for it because according to him, physics doesn’t always need to be explained with math…
What he does is he will clog up your comments with such reams of his spam and silly pontificating that makes it impossible for anyone to extract any valid content from honest commentators. He's a tool of the alarmist machine working to make critical assessment of the climate scam look unalluring.
Great article.
ReplyDeleteIt's mathematical law...beyond physics law. The average of a sequential distribution is necessarily found around the middle of that distribution, not at either extremity, and thus, in the case of the atmosphere, the bottom must be warmer than the average - middle -, etc, and this arises without any concern or reference to "greenhouse gases" at all, although the "GHG" water vapour makes it cooler, not warmer. The entire basic premises of climate science are wrong, and misattributed.
Thanks Joe! and thanks for all your many great articles.
DeleteI was wondering if you had any thoughts as to applying this center of mass concept to the odd case of Venus heated from both top and bottom?
"...is dominated by convection/pressure/lapse rate in the troposphere up to where the tropopause begins at pressure = 0.1bar. When P < 0.1 bar, the atmosphere is too thin to sustain convection..."
ReplyDeleteIf I may,
1) the tropopause is defined by temperature, not pressure. The tropopause is, on average, about twice as high at the equator than it is at the poles.
2) the vertical limit on convection is, as well, defined by temperature not by pressure. If you have a low/mid-level (below the observed tropopause) temperature inversion, that inversion will cap any convection that cannot exceed the inversion differential...i.e. across most of the tropics. The strength of the Tradewind Inversion caps any deep convection to areas of localized surface convergence (easterly waves, sea breeze fronts, etc.), areas of broad upper-level divergence & such but the low-level tradewind cumulus area there nearly 24/7.
Regards
Please read Robinson & Catling Nature 2014. The whole point of that paper is to explain why the tropopause on all those planets is located at P=0.1bar, I.e. The height of the tropopause is set by pressure alone, not radiative forcing from GHGs.
DeleteIm puzzled by the 0.1 bar aspect.
DeleteI can see that at some point density becomes too low to sustain convection but on Earth it is the temperature inversion at the tropopause which stops
further convection and thereby creates the tropopause.
Additionally, there is a slow large scale convective overturning in the stratosphere too. The Brewer Dobson Circulation.
"Please read Robinson & Catling Nature 2014. The whole point of that paper is to explain why the tropopause on all those planets is located at P=0.1bar, I.e. The height of the tropopause is set by pressure alone..."
DeleteMS - Thanks, but I'm not going to pay the $5. I never once said or implied the tropopause is set by radiative forcing from GHG. You are all missing the point that these figures are based on a "Standard Atmosphere" of a fixed surface temperature. The tropopause is set from the surface temperature & the lapse rate that follows from the surface temperature. That is why the tropopause at the colder poles is lower in height (higher pressure) and is higher in height (lower in pressure) at the warmer equator.
Also, convection in the troposphere is capped by the level of the tropopause (regardless what pressure level it is) because the tropopause is defined by the WMO & AMS as a change in the lapse rate not by a fixed pressure level. This has been known since it's discovery back in the late 1800s and is basic meteorology & just because Robinson & Catling want to redefine it does not make it so.
Now, regarding your model/equation - if you can change the surface temperature & it will correctly reflect the change in the height of the tropopause, then it holds promise but if you are presuming the tropopause is at a fixed height for the whole globe (pole to equator), it has problems & is wrong.
"Yet the radiosonde data clearly shows that over most of the Earths solid surface, most of the year round, the ground is actually cooler than the air above it."
ReplyDeleteRadiosondes do not actually measure the temperature of the "ground". They start by measuring the temperature of the air about 1-2 meters above the ground, which is persistently cooler than the ground itself. Experiments have shown that the coldest part of a nighttime near the ground temperature inversion is about 10 cm above the ground with the ground itself being several degrees warmer than that minimum temp.
Carl
"Radiosondes do not actually measure the temperature of the "ground". They start by measuring the temperature of the air about 1-2 meters above the ground,
DeleteI didn't say they did. In fact most soundings begin at 150-200 meters above the ground, not 1-2 meters.
What I am referring to is the ability to closely predict the surface temperature from radiosonde data, compared to actual ground based measurements.
This can be achieved by finding the altitude of -18º C in any particular sounding and then using the normal lapse rate of 6.5º C per km, to calculate the surface temperature.
Where the radiosonde data predicts a higher temperature than the actual ground based measurement, then the air directly above the surface is obviously warmer than the ground and vice-versa.
Over most of the Earths solid surface however, there is a temperature inversion in the first 4' above the ground. This is the reason why Stevenson screens are always placed 4' above the ground.
"Experiments have shown that the coldest part of a nighttime near the ground temperature inversion is about 10 cm above the ground with the ground itself being several degrees warmer than that minimum temp."
That will obviously depend on time of year and location. However, at the opposite side of that diurnal cycle, i.e., the warmest part of the day, the air will become warmer than the ground and a near surface temperature inversion will occur in the first 4' above the ground.
W R Pratt
"This can be achieved by finding the altitude of -18º C in any particular sounding and then using the normal lapse rate of 6.5º C per km, to calculate the surface temperature"
DeleteNice, and do you have a link to the barometric pressure readings that correspond to height where temperature = -18C? And the surface pressure at that same location. By what I'm showing, that height should be where pressure = ~.5*surface pressure.
Hi MS,
DeleteThis is the link to the soundings I use: http://weather.uwyo.edu/upperair/sounding.html
I would say it looks to me, though I haven't looked at pressure until now, that -18º C will be at approximately .5* the surface pressure in ant given sounding. Close enough to back up your work above.
W R Pratt
Thanks much, when I get a chance I hope to work out several specific examples, and if you have any to share, please let me know. Thanks again for your help.
DeleteYou are welcome.
DeleteI do have another piece of corroborating evidence I would like to share with you as I said in the email I sent you. If you could reply to that we can discus it further offline.
W
MS,
DeleteHaving had a quick look at the radiosonde data in the link I gave, I'm not seeing any direct link between pressure @ .5 and ERL of -18º C.
All the evidence I have, indicates that Earths atmosphere is heated by direct incident EMR. Pressure is the result, not the cause, but to a large extent pressure, is determined by gravity.
While obviously there is a certain amount of variation, the vertical pressure gradient appears to be fairly stable compared to the temperature gradient.
W R Pratt
Here is the relevant extract from the R & C paper:
ReplyDelete"the tropopause separates a stratosphere with a temperature profile that is controlled by the absorption of short-wave solar radiation, from a region below characterized by convection, weather and clouds5, 6. However, it is not obvious why the tropopause occurs at the specific pressure near 0.1 bar. Here we use a simple, physically based model7 to demonstrate that, at atmospheric pressures lower than 0.1 bar, transparency to thermal radiation allows short-wave heating to dominate, creating a stratosphere. At higher pressures, atmospheres become opaque to thermal radiation, causing temperatures to increase with depth and convection to ensue. A common dependence of infrared opacity on pressure, arising from the shared physics of molecular absorption, sets the 0.1 bar tropopause"
So it looks like the pressure reduction to 0.1mb somehow alters the ability of the air to respond to incoming solar radiation such that a temperature inversion is created at or near 0.1mb largely independently of composition though for Earth it is the accumulation of ozone around that pressure point that does the trick for Earth.
That's the money quote: "At higher pressures, atmospheres become opaque to thermal radiation, causing temperatures to increase with depth and convection to ensue. A common dependence of infrared opacity on pressure, arising from the shared physics of molecular absorption, sets the 0.1 bar tropopause"
ReplyDelete"vertical stratification, with warmer layers above and cooler layers below, makes the stratosphere dynamically stable: there is no regular convection and associated turbulence in this part of the atmosphere. The top of the stratosphere is called the stratopause, above which the temperature decreases with height."
https://www.princeton.edu/~achaney/tmve/wiki100k/docs/Stratosphere.html
Since the Brewer Dobson circulation is so slow perhaps it has little effect?
I just added at the end of the post additional reasons why the ERL is set by pressure, not temperature or GHG radiative forcing.
DeletePlease forgive my ignorance with these questions.
ReplyDeleteHow does the fact that the depth of the atmosphere at the equator is more than double the depth at the poles affect these discussions? (ie: 7km poles vs. 18km equator)
Is this fact considered within the relevant calculations? Further, how is this determined and factored in on other planets? Is the Venusian atmosphere also twice as deep at the equator than the poles? If not, how does this change things?
We are dealing with global averages in this post, but the same general principle should apply most anywhere since the lapse rate = -g/Cp everywhere. The heat capacity at constant pressure Cp varies widely depending on the pressure and water vapor content, adjusting the lapse rate accordingly. Also the equilibrium temperature with the Sun varies with solar insolation, thus the surface temperature calculation at a given location, but as a global average it is 255K.
DeleteFig showing lapse rate of the "standard" average atmosphere, poles, and tropics:
http://globalwarmingsolved.com/wp-content/uploads/2013/12/non-standard.jpg
"If I may,
Delete1) the tropopause is defined by temperature, not pressure. The tropopause is, on average, about twice as high at the equator than it is at the poles."
"Please read Robinson & Catling Nature 2014. The whole point of that paper is to explain why the tropopause on all those planets is located at P=0.1bar, I.e. The height of the tropopause is set by pressure alone, not radiative forcing from GHGs. "
OK...at first you disagree with me...then, here, you agree with me...that the tropopause height is 'not' fixed but varies with the surface temperature & is defined as a change in lapse rate which agrees with the WMO & AMS. Your web link confirms that. Please explain...which is it?
Thanks!
Good article
ReplyDeleteComment has been made that the results above do not apply very well to Mars and Venus.
This is only to be expected.
The Barometric Equations and the Perfect Gas Laws are only true if the Specific Heat Capacity stays constant while the temperature changes.
This is true for our atmosphere mainly N2 and O2.
It is not true for Mars and Venus where CO2 forms a major part of the atmosphere.
http://www.engineeringtoolbox.com/carbon-dioxide-d_974.html
Bryan
Thanks Bryan, that's a very helpful point, and probably explains why the CoM works for Earth and Titan, but not Mars and Venus.
DeleteTitan atmosphere has similar non-greenhouse-gas percentages to Earth:
"98.4% nitrogen with the remaining 1.6% composed mostly of methane (1.4%) and hydrogen (0.1–0.2%)"
Any other thoughts on the center of mass concept?
Thanks again.
A general point in the hope that it will assist.
ReplyDeleteAny planet can only retain an atmosphere if energy in equals energy out over the long term.
That requires a specific rate of cooling with height which is the 'ideal' lapse rate determined only by mass and gravity. Insolation then determines the length of vertical travel for that ideal lapse rate.
Every planet has an atmosphere with a different composition and there is vertical layering plus horizontal mixing which creates a vast plethora of different lapse rates from place to place and time to time.
However, ALL those different actual lapse rates MUST net out to the ideal lapse rate if the atmosphere is to be retained.
Variable convection sees to it that they do all net out to the ideal lapse rate.
There will be differences from planet to planet depending on how the different compositions configure convective overturning but the basic principle applies regardless.
The head post is essentially correct even if refinements are possible.
Well Stephen, I'm glad to see that you now appear to agree with me (and what's in my book published in March) that there is downward convection transferring thermal energy originally absorbed in the colder upper troposphere (especially on Venus and Uranus) to warmer regions and even into the warmer surface.
DeleteWhen I wrote (two years ago) about downward heat transfer by convection (which includes diffusion) you seemed to think I was mistaken. I am not mistaken Stephen, and your comment clearly agrees with what I have said all along, namely that there has to be a non-radiative (convective) heat transfer downwards in lieu of the assumed transfer of thermal energy by radiation into the surface which cannot happen for a warmer surface.
Doug,
DeleteAs I recall, two years ago,you denied downward convection and insisted on downward diffusion.
The former involves movement within the gravitational field thereby changing PE to KE whereas the latter does not.
Furthermore, the energy that convects downward is not initially absorbed in the colder upper troposphere from incoming solar energy. Instead it is in the form of gravitational potential energy created by uplift from lower levels that then descends and reverts to heat as it does so.
You can have direct absorption of energy from radiative gases higher up and that will be conducted downward as well as upward but it often doesn't reach the surface where there is convective overturning in a lower layer such as in our troposphere beneath or warmer ozone heated stratosphere.
So, no we are not yet in agreement.
There is indeed warming of the surface from convective overturning but that is not diffusion and describing it as a downward flow of thermal energy is incorrect because you miss out the conversion of thermal energy (KE) to gravitational potential energy (GPE) and back again.
MS, I think you should consider highlighting the two last posts of yours as features posts or something. They are both beyond my professional skills but seem to warrant a wider discussion.
ReplyDeleteThanks. Blogger doesn't have a "sticky post" feature to keep posts at the top, but I am going to be posting more on these issues with new posts linking back to these posts, so hopefully the discussion will continue. Thanks for your interest.
DeleteNote to Doug Cotton: I've received several complaints from readers to stop allowing you to spam threads. You've made your same points many times. The purpose of this thread is my GHE derivation, not your book, so I'm not publishing any more of your comments. Take care.
ReplyDeleteI think you are on the right track, but as far a Venus not working out, well it's hard to apply something derived from the ideal gas laws to non-gases.
DeleteThe surface of Venus basically has no gas at all, it really only has CO2 as a super-critical fluid.
For your formula to work, you need to apply it only to gases - I suggest only going down into Venus's atmosphere to the bottom of the gaseous envelope - not to the surface.
However, it's correct to say that Venus is not hot because of the GHE; how can greenhouse gases 'trap heat' and keep the surface warm all through the Venusian 58-day 'night' when there is no sun?
Less that 10% of the sun's energy reaches the surface anyway.
In the video shown here CO2 warming in the lower atmosphere is attributed to the following process: "....Near the Earth's surface, carbon dioxide absorbs radiation escaping Earth, but before it can radiate the energy to space, frequent collisions with other molecules in the dense lower atmosphere force the carbon dioxide to release energy as heat, thus warming the air.....". Does your model consider this?
ReplyDeletehttp://www.ucar.edu/news/releases/2006/thermosphere.shtml
tsh