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Comments 151 to 200:

  1. One Planet Only Forever at 07:19 AM on 2 December 2018
    But their Emails!

    Instead of trying to angle to get David's emails though some version of a FOIA, maybe Drs. Hughes and Overpeck could Publicly request tha David Schnare do the honorable things of being totally transparent "In the Public Interest he claims to be Concerned about" by sharing all of his emails - without reviewing them for potential Personal Confidential Interests.

  2. One Planet Only Forever at 06:32 AM on 2 December 2018
    But their Emails!

    SInce David Schnare claims to be performing a Public Service through this Public Process it seems reasonable that someone could do FOIA request for all of his emails, starting form the date he began using this Public Mechanism to perform this Public Service.

  3. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    dkeierleber @15,

    Can I provide references? Not easily.

    On line, perhaps Siegel & Howell (1971) may be of use to you. Alternatively, you may wish to narrow your enquiry within what is a piece of physics that doesn't get described within published literature in the manner that is understandable to the general reader. Or more correctly, I have never found anything on-line more complete than the likes of this overly-simplistic UCAR page.

  4. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    @14, MA Rodger

    Can you provide references for your response?

  5. But their Emails!

    The Consensus on Anthropogenic Global Warming Matters

    http://journals.sagepub.com/doi/abs/10.1177/0270467617707079?journalCode=bsta

    Moderator Response:

    [DB] Please set image widths to below 500.

  6. But their Emails!

    Michael Mann vs. Climate Deniers & more

  7. But their Emails!

    i do love the fact that worshippers at the "church of the eternally concerned" hold climate scientists to much higher standards than just about any other human - living or dead

    I beleive even Einstein had issues with data conflicting with theory

    the earth is round, evolution is the best theory that explains the diverstity of life on earth and AGW is the best thoery that explains the data - get over it

  8. But their Emails!

    It's a bit disappointing that already, and even here, David Kirtley's concerns described above are being fulfilled- cherry-picking, misrepresentation, fake concern etc.

    JP66 quoted a passage out of context, which was part of an email discussion that went on for several emails (10 July 2000 email by Ray Bradley, with replies by other people). The discussion was evidence of scientists doing science and working hard, talking together, to try to get to the bottom of what was happening 1000 years ago, well before thermometers and barometers.

    Even if JP66 didn't look at the other emails in the discussion, they could hardly have missed key lines in the one he/she cherry-picked. After explaining some of the difficulties of sorting through data to get valuable information, Ray Bradley wrote:

    In Ch 7 we will try to discuss some of these issues, in the limited space available. Perhaps the best thing at this stage is to simply point out the inherent uncertainties and point the way towards how these uncertainties can be reduced. Malcolm & I are working with Mike Mann to do just that.

    That's leaving aside the fact that the email thread was yet another example showing the dedication of scientists. They were working late into the night. (Researchers do not stick to 9-5 hours. For a lot of them, like the ones writing these emails, it's a 24-7 commitment.)

    Now if anyone is concerned about how scientists view or speak about fake sceptics, they hold them in the same contempt as I do. Who can blame them?

  9. But their Emails!

    JP66 @8

    Virtually every peer-reviewed article backs up the theory of athropogenic global warming mostly forced by massive fossil fuel use.

    The 97% consensus on global warming

     

    If you're straddling a fence then one half of your body is being crushed up against the wall of evidence.

    The models being discussed in these taken out of context emails don't "prove" that anthropogenic global warming is happening, they are an attempt to model what we might expect to see in coming years given specific forcings. And even if the models could be discredited totally - which they haven't been - it doesn't change the basic science telling us why the globe is warming so rapidly and what is almost certainly the main forcing. Coarbon dioxide absorbing huge amounts of longwave EM ratiated by the Earth.

    A forcing that has been understood for well over a century and more than a century ago climate sensitivity was calculated before we even understood the fundamental mechanism that causes the greenhouse effect. Namely photons being quantized to be absorbed by certain molecules but not others.

    Svante Arrhenius - Climate Sensitivity

     

    The idea is not to wait until there is nothing we can do about this growing global catastrophe, the signal rose above the noice over two decades ago. The idea is to let the overwhelming evidence on this existential issue determine policy. Something that still isn't happening not because the evidence is not far above a rational doubt, but because people skilled in hitting the scientific method where it's most vulnerable - in the constant application of skepticism - keep demanding 100% certainty before we change anything. There is zero genuine skepticism being applied by these people to their own positions.

    That's not science, I'm not going to put in blunt words what it is but that is not science and there is nothing sacrosanct in playing silly bastards with an issue that is already killing large numbers of people every year and driving entire essential ecosystems like coral reefs to the edge of existance.

  10. But their Emails!

    JP66, the email you quote is a single email relating to climategate taken completely out of context, which shows the whole problem with these thefts / hacks. It's hard to even know what they are really saying, other than they appear to be arguing whether a paleo climate reconstruction of the medieval warm period is reliable, notice its in reference to "a" reconstruction.

    I don't see what "theory" this undermines. Greenhouse gas theory, human impacts on climate,and future modelling of temperatures obviously do not rely on reconstructions of the medieval warm period.

    What theory do you claim it undermines? What is it you think they are really saying?

    Yes they are also talking about problems they are having with analysing the past, misakes that might have ocassionally been made, people attacking their work and how they should respond to this. Wouldn't any normal person do this? Why do you think this is somehow nefarious or abnormal?

    If this is the so called smoking gun in climategate its laughable.

    I do agree with you if the latest data and the accepted theory diverge then question the theory, but this is not apparent in this case.  Also question whether the data is reliable, as it often turns out the data is wrong, for example the problems where the satellite temperature record originally showed a cooling, when it turned out there were problems with the satellite sensors or something.

    Please note that many groups have analysed the MWP and found it was no warmer than temperatures over the last decade.

     

    Moderator Response:

    [DB] Indeed, the first volume of the 4th National Climate Assessment released by the Trump Administration found this to be the case, with regards to the MWP:

    Last 1,700 years

  11. But their Emails!

    I need to put my thought in context.  Science to me is sacrosanct.  A key element of science is the understanding that when data contradicts a theory then one discusses the validity of said theory; one does NOT worry about responding to "the antis".  As a scientist one should question the theory.  That is incredibly simple and extremely damning to me.

  12. But their Emails!

    Avowed fence sitter here . . . 

     

    I am reading the entire thread of emails and following the discussion, but I am afraid it does not put climatologists in a good light when I read something like this . . .


    But there are real questions to be asked of the paleo reconstruction. First, I should point out that we calibrated versus 1902-1980, then "verified" the approach using an independent data set for 1854-1901. The results were good, giving me confidence that if we had a comparable proxy data set for post-1980 (we don't!) our proxy-based reconstruction would capture that period well. Unfortunately, the proxy network we used has not been updated, and furthermore there are many/some/ tree ring sites where there has been a "decoupling" between the long-term relationship between climate and tree growth, so that things fall apart in recent decades....this makes it very difficult to demonstrate what I just claimed. We can only call on evidence from many other proxies for "unprecedented" states in recent years (e.g. glaciers, isotopes in tropical ice etc..). But there are (at least) two other problems — Keith Briffa points out that the very strong trend in the 20th century calibration period accounts for much of the success of our calibration and makes it unlikely that we would be able be able to reconstruct such an extraordinary period as the 1990s with much success (I may be mis-quoting him somewhat, but that is the general thrust of his criticism). Indeed, in the verification period, the biggest "miss" was an apparently very warm year in the late 19th century that we did not get right at all. This makes criticisms of the "antis" difficult to respond to (they have not yet risen to this level of sophistication, but they are "on the scent").

    Moderator Response:

    [DB] For context, if you are going to quote an email exchange here, please also include who sent the email and to whom they sent it, including the date.  That will enable others to help you improve your understanding of the science in question.

    Briffa and the divergence issue is discussed here and here.

  13. But their Emails!

    Curiously enough I was reading this article at the end of a television episode of Dr Who, where the Dr time travelled back to the time of King James and the persecution of so called witches. I thought it an ironic sort of coincidence.

  14. But their Emails!

    What you have with the EELI and other climate sceptics groups is a marriage of convenience between fossil fuel interests, libertarian small government fanatics, scientific cranks, conspiracy theory people, ignoramuses, and hired guns. Read any climate sceptics website and you find these characters lurking.  

    Their propaganda is nothing more than personal attacks,  material taken out of context, and bullying. They are not genuine sceptics or whistle blowers, they traffic in muck raking. They have no shame, no conscience, and no ethical standards, and know nothing about anything of value.

  15. But their Emails!

    Good catch, John. Changes made.

  16. But their Emails!

    David Kirtley: Recommend that you change the acronym for the Energy and Environment Legal Institute from E&E to EELI. The acronym E&E is used by a E&E News -  respected news organization focusing on energy and the environment.

  17. But their Emails!

    It's really quite simple: Unless we stop burning fossil fuels, civilization will collapse from the consequences of Global Warming. But if we stopped burning fossil fuels immediately, civilization would collapse before the end of the week. Of course, this is not a real choice, we all get up in the morning and pretend that what we do isn't ruining the future. We are all lying to ourselves.

  18. But their Emails!

    "One wonders, if the shoe were on the other foot, and the private correspondence and paperwork of E&E were made available, what might the public learn about this “charity."

    Probably that its funding comes from individuals and corporations closely associated with the fossil fuel sector like the Kochs and Exxon Mobil. 

    This is the world turned inside out, where professionals carrying out their duty as part of an endeavour to understand the natural world in a way that has great benefit to everyone must constantly defend themselves from a very tiny yet incredibly well funded front group.

    And this is a multi phased attack on the science, not only is the intent to get more raw material that can then be feed into the widespread disinformation machine created by the fossil fuel sector, it will also have a chlling effect on scientists who will then be looking over their shoulders for the next attack.

    And it also encourages people who don't want any change in their lives to become ever more resistant to change as they are convinced once again the "evil elites" are out to get them.

    This will only end when the fossil fuel sector no longer has the millions of dollars to spend fueling this disinformation machine. The British Royal Society asked Exxon Mobil to please stop funding climate change denial over a decade ago, but the only thing that has changed is the money from Exxon Mobil to the network of denial "think tanks" has gone "dark" now.

    And as long as the money keeps flwoing to these groups the garbage will keep shooting out of them. 88 people just died in a climate change related disaster in California and many more are unaccounted for and the catastrophic impacts of a hothouse world are sobering to say the least. The IPCC has just made clear, we have very little time left to take real measures to avoid a world that will almost certainly be unable to support our current population plus some.

    And the people who take money from the fossil fuel sector still try and prevent those real measures from being implemented because it would mean they would have to find another occupation.

    There will always be a need for people who fill the roll scientists do now, do we really have a need for people who distort reality in such a way it places our entire species at risk of extinction...

  19. But their Emails!

    Gunslingers tend to have what are these days politely called "chaotic lifestyles" and Schnare appears to coincide with both of those attributes.

    If there's a single good thing that's come out of the whole episode, it may be the photochop in this article. :-)

  20. Discussing climate change on the net

    Sunspot @21 ~ intrigued by your earlier comment, I chased up the comments column of a Yahoo climate article.

    The article was quite fair and reasonable (on AGW effects) . . . but Oh My . . . the comments column was a Niagara of 1- to 3-sentence denialist mini-rants.   Maybe 98% denialist?   Absolutely no way could that represent a randomized cross-section of opinion.

    Is Yahoo being a magnet to half the crazy galoots in the USA?   Do the crazy galoots simply join in there (having been rejected by their friends & relatives) in order to air their opinions & vent their anger?   And yes, one could well believe that some of them are there as "paid actors" . . . or, in this modern automated age, perhaps many of them are simply Heartland-funded bots?

    What is not clear to me is Yahoo's business plan, in all this nonsense.   To gain reading clicks by stirring up the crazies, allowing them to vent in an echo-chamber . . . and keep them watching/clicking?

    In comparison, the comments columns of WattsUp are almost half-sane.   Yes, about a third of the posters are so intellectually insane that they totally dismiss the global warming mechanism of CO2/GHG's.   And three-quarters of them are rabid political extremists, to whom the term charity (let alone the word tax) is anathema.   A further one-fifth are such victims of their own Motivated Reasoning, that they say that around 90% of recent rapid global warming comes from 70-year and/or 1000-year oceanic cycles (or from cosmic rays causing clouding or unclouding . . . or whatever).

    I don't bother closely reading the WattsUp articles ~ they are mostly trash & sour-grapes "spin".   But I do skim through the comments super-fast, lookin for "names" with a track record of sane intelligence (names such as Nick Stokes, Mosher, and a few others also worth reading) ~ posters who are cool oases in that intellectual desert.

  21. Discussing climate change on the net

    While it is tempting to think that something like Yahoo comments presents a randomized cross-section of opinion, unfortunately, like most things on the internet it seems, this is far from the truth. Comments are arranged to elicit response and keep me on the page. And when Yahoo doesn't like what I am saying, the page I am on will stop getting new comments from anyone else, and the link will disappear from the main page. All clear manipulation. I call them out occasionally for it, for all the good that does. I have never seen any mention of this anywhere, but I can see it happening all the time.

    I do like the free email, though... :-)

  22. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    dkeiereber @13,
    Gas molecules do increasingly whiz about with increasing temperature. If the gas contains polyatomic molecules (like CO2) it will have a higher Specific Heat Capacity as there will also be energy being absorbed into extra rotation and vibration as temperature increases. The vibrational energy can be transferred to other molecules/atoms as kinetic, rotational or vibrational energy but can also result in the emission of a photon. So the answer to your question "Can the higher quantum state of an excited GHG molecule be transferred to another molecule through a collision?" is 'Yes.'
    And the opposite can occur; a collision or a photon of the correct wavelength can set a polyatomic molecule vibrating in a particular mode.
    Quantum rules apply to vibration (and rotation) so the photon is always of the same wavelength, abet the rotational energy and kinetic energy do create small variations (broadening) in wavelength for emitted/absorbed photons.
    Relative to the energy transferred between molecules/atoms in a gas, the emitting/absorption of photons are a rare events and most absorbed photons will become added to the energy in the gas rather than being immediately emitted as another photon.

  23. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    Pretty sure this is on topic. I’m struggling with the details of the physics. BTW, I thought the video was good but it didn’t go far enough. My question is whether the absorption of infrared radiation (IR) by greenhouse gas molecules directly warms the air. I have seen an explanation regarding the hot atmosphere giving off IR. But, since 1859, we know that the majority of the atmosphere doesn’t absorb IR.So I'm assuming it can't emit IR. The atmosphere isn't a black body (maybe a gray body).

    GHGs absorb IR because they have at least three atoms and two bonds allowing more than one quantum vibrational state. A GHG molecule is boosted to a higher state only by a photon with the right energy. The energy must match the energy gap between two allowed quantum states of the molecule.

    Similarly, it seems the molecule could only emit a photon of the same energy and return to its base state. Some of the emitted photons will be reabsorbed by the Earth causing further warming.

    But gas molecules are also in kinetic motion---whizzing about. The faster the molecules move---the more kinetic energy they have---the warmer the air is. Can the higher quantum state of an excited GHG molecule be transferred to another molecule through a collision? I know that the kinetic energy isn’t quantized so it seems that in order for that to happen the excited molecule would have to emit a lower energy photon, to return to its base state, as part of the energy transferring collision---the transferred kinetic energy plus the energy of the photon would have to equal the energy gap between the two allowed quantum states---kind of the reverse of collisional broadening of the absorption bands.

    I hope I’ve made my question clear and I’d really like to know the answer.

  24. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    Ken,

    I am astonished that someone who claims to be interested in the science behind AGW is so ignorant of the basic data.  All gases follow the log relationship.  Please provide a citation to support your wild claim that methane and other gases do not. 

    You are about 100 years behind in your understanding of the science.  Claiming you want a scientific discussion while criticizing those who know the science is insulting.  Follow your own advice instead of making political, insulting statements.    You appear to have informed yourself with a brief review of nonsense (non-science) sites on the internet. 

    Your wild claims contradict your claims that you want a non-poloitical discussion.  You are the only one who is making wild, incorrect claims.

    People here are willing to help you obtain an understanding of the science and will provide you references to the science.  If you want to make false assertions and insult those who reply to you they will quickly lose interest. Try to up your game.

  25. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    Ken @8,

    Although it is not relevant to the substance of this interchange, you evidently have a different understanding of the term "directly proportional" than I do. And it seems my understanding is shared with Wikipedia.

    As for the log relationship resulting in there being a diminishing relationship between rising CO2 levels and extra direct climate forcing, there is also another non-linear relationship - the greater the forcing imposed on climate, the greater the harm to humanity from a unit rise in that forcing. Mankind really does not want to arrive at a point where CO2 emissions have a negligible direct effect on climate forcing. If we do arrive we will find that 'negligible' increases in CO2 forcing will nontheless bring with it non-negligable impacts, either in resulting feedbacks or in dramatic climatical effects.

    You say that "someone must have developed the first partial derivative of Temp with respect to CO2" but do not express this overtly as a question or why the inception of this work would be relevant to policy decisions today.

  26. Discussing climate change on the net

    "If you think education is expensive - try ignorance"

  27. Discussing climate change on the net

    Eclectic 18, yes exactly.

    "Nothing in all the world is more dangerous than sincere ignorance and conscientious stupidity." - Martin Luther King, Jr. quotes from BrainyQuote.com."

  28. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    Ken @8, I think I can see where you are going with this. Before you waste your time posting a whole lot of data, read the following:

    skepticalscience.com/saturated-co2-effect.htm

  29. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    So we can assume you are now satisfied on the questions of snowball earth and why Mars isnt hot? Given your stated background, it would seem that you could have easily consulted a text book.

    The amount of radiation acting on the earths surface is what is proportional to CO2. Double the CO2 concentration to double the forcing. The effect of change from 200ppm to 400ppm is same as change from 400ppm to 800ppm. The effect on surface radiation can be directly measured.

    The surface temperature that results from such a change in radiation is not so straightforward because of feedbacks. You cant change the earths temperature up or down without also affecting the amount of water in the atmosphere and the albedo. Hence the relationship of CO2 to temperature is much more complex.

  30. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    MA Rodger at 02:58 AM on 29 November, 2018

    I appreciate your bringing up the log relationship for CO2 and GHG effictiveness.  That was going to be my next question, because no one seems to want to address it.  I believe what you meant by not "directly proportional" was "not linear", because it is directly proportional, but in a ln (natural log) curve, and that means it is a smooth, continuous function.  CO2 GHG effectiveness is a ln function of CO2 consentration.  This means that the slope of that ln curve is the effectiveness.  The problem is that the slope of the ln curve (or the first partial derivative) is equal to 1/(CO2 consentration).  For example, at 200 ppm the slope is 1/200  and at 400 ppm the slope is 1/400.  Eventually the ln curve approaches horizontal, which means the GHG effectiveness is reduced by 50% when the CO2 consentration doubles.  Any engineering of scientific system that follows the ln curve has the same result, the more you have of the independent variable (x-axis) the less effective the dependent variable is.  

    The best physical example of this is laying a chain on the ground, holding one end and running toward the other end.  You move the chain quickly at first, but pretty soon you can hardly move the chain and your speed, or effectiveness, goes to zero.

    I realize the interactions in the atmosphere are complex, but that complexity does not negate the properties of the natural log function.  Methane and other gases do not follow the ln curve, but CO2 and water vapor do follow it.

    If more CO2 means more temperature at some ratio, someone must have developed the first partial derivative of Temp with respect to CO2, otherwise how can we make estimates of containing Temp by reducing CO2 by a certain amount over a certain number of years.

    Just to clear the air here, I am very serious about wanting to know how the atmosphere really works.  I am a retired AF pilot, I have a BS and MS in aerospace and aeronautical engineering, a MS in software engineering/computer science.  I have worked in these fields and taught university courses for over 40 years.  I am a serious amateur astronmer and astro photographer, and design custom astronomy equipment.  

    I am sorry if scientific questions and comments upset people.  I was hoping to find people who want to find real answers and leave people and politics out of the scientific discussions.

    I am traveling right now, but will answer the other comments and show some data I have next week.

    Thank you for your time.

    Moderator Response:

    [DB] Inflammatory rhetoric snipped.  Please read this venue's Comments Policy and stick to the science and all will be fine.  Thanks!

  31. Discussing climate change on the net

    Sunspot @17 , please keep up the good work!

    The "Russians" (as you call them ~ but doubtless including some "Home-grown Russians") are driven to public lying, by their own warped psychologies plus, in some cases the regular receipt of "dark money".  (Old psychological experiments, from the 1970's and earlier, show that even quite small rewards can be remarkably motivating, in influencing actions and beliefs.)

    The lies find fertile soil in the scientific ignorance of many citizens ~ and fertile soil in those intelligent/educated citizens who desperately wish to believe the lies & distortions.  And all of them ~ the good, the bad, and the ugly ~ are voters.

    Besides, Sunspot, I would hope that you find an additional measure of fun and entertainment in "Striking a blow for Liberty".   It all adds up, over time.

  32. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    Ken, so just how much effort did you put into trying to answer your own question? Frankly looks like grasping at a straw because perhaps you cant imagine a solution to climate change that is compatiable with your political philosophy? Or if you are simply trolling, perhaps its time to find another site for your amusement.

  33. Discussing climate change on the net

    I frequently comment on Climate Change articles at Yahoo. I'm Sunspot there too. I present them with scientific facts. I don't care who "believes" me or not. Just the fact that the truth is there helps counteract all the lies. I also frquently call out the trolls, and I call them Russians. Which may be true. There are people over there - "Gooner(something), "It's Me", "Fun", and numerous others are regular features there and must be getting paid to spend that much time at it. I'm retired. It seems futile sometimes, but there are times when I get thanked for explaining something concisely, like I did yesterday with the old "but they predicted an Ice Age in the 70s" song.

    My favorite question this time of year is "Do you know what causes winter?". Because they don't! They really expect Global Warming to eliminate winter. But nobody ever explains the seasons. And with all the discussions I've seen on the TV, I have never seen an explanation of why it gets cold in the winter. If we don't educate ourselves and others, it's truly over... I, for one, intend to keep doing my part.

  34. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    I am an old enough geezer & what catches young folks' attention is somehat outside my zone of understanding. So I think it might suit the generation it is aimed at, and kudos to Climate Adam for trying. I enjoyed it and watched to the end.

  35. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    Ken @4,

    A very quick reply, (but perhaps not as quick as the Moderator Response).

    (1) The GHG effect from CO2 is not "directly proportional" to the level of CO2. It is a lot more complicated than that. For small changes in the terrestrial atmosphere (200ppm to 1,200ppm) the relatinship is logarthmic. However your general assertion that more CO2 would result in more warming would be correct in most circumstances.

    (2) The Snowball Earth episodes were a long time ago so their circumstance are not very well nailed down. The favourite cause of Snowball Earth is that it begins with lowering levels of CO2 allowing global temperature to drop and this cooling is amplified by an increase in albedo - the extensive snow/ice fields increasing the amount of sunlight being reflected into space and so not warming the planet. Once a Snowball Earth has formed, it requires a very large increase in GHG (ie CO2) to warm up the planet enough to melt the snow/ice and release it from the Snowball. Note that through this time, the sun was much weaker. By the end of the Snowball Earth eposides, it would still have been 6% weaker than today, roughly equal to losing a third of today's GHG effect.

    (3) The Martian atmosphere is almost all CO2 and, although there is little gas in the Martian atmosphere, it still has more CO2 than Earth. Indeed Mars (95% x 6mb) has well over ten times the CO2 of Earth (0.06%[mass] x 1,000mb) in its atmosphere. The problem for a GHG effect on Mars is not the level of CO2 but the lack of any other GHGs to fill in the gaps of the electro-magnetic spectrum not being insulated by the CO2. On Earth, the CO2 warms the planet enough to boost H2O levels which then provides this extra insulation. [The Mars GHG is a bit like going out on a snowy day wearing just a hat and gloves. They don't keep you very warm. Even thick furry hat & gloves will not improve the situation.] And additionally, Mars has on 43% of the sunlight that Earth enjoys. A cold Mars with its CO2-laden atmosphere and a warm Earth with just a small portion of CO2 in a nitrogen atmosphere is what the theory expects and exactly what we see.

  36. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    If atmospheric heating is directly proportional to C02 consentration, how did the Earth go through at least three "Snow Ball Earth" periods when the atmosphere was essentially 100% C02?  Also, why is it so cold on Mars when the atmosphere may be thin, but it is 93% C02.  

    Moderator Response:

    [DB] "how did the Earth go through at least three "Snow Ball Earth" periods when the atmosphere was essentially 100% C02"

    That's nonsense.  Atmospheric carbon dioxide has never been more than even 50% of the total:

    Atmospheric composition over geologic time

    "why is it so cold on Mars when the atmosphere may be thin, but it is 93% C02"

    Less solar insolation received at the surface due to the greater distance from the Sun.  

    Please note that posting comments here at SkS is a privilege, not a right.  This privilege can and will be rescinded if the posting individual continues to treat adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Moderating this site is a tiresome chore, particularly when commentators repeatedly submit offensive or off-topic posts or simply make things up, as you do. We really appreciate people's cooperation in abiding by the Comments Policy, which is largely responsible for the quality of this site. 
     
    Finally, please understand that moderation policies are not open for discussion.  If you find yourself incapable of abiding by these common set of rules that everyone else observes, then a change of venues is in the offing.

    Please take the time to review the policy and ensure future comments are in full compliance with it.  Thanks for your understanding and compliance in this matter.

  37. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    Much better link => https://climatekids.nasa.gov/greenhouse-effect/

  38. Jerry Mitrovica: Current Sea Level Rise is Anomalous. We've Seen Nothing Like it for the Last 10,000 Years

    I'm not seeing the video on this page, but assume it is:

    https://www.youtube.com/watch?v=RhdY-ZezK7w

    By the way, I suppose a few things have changed since 2012, in particular understanding how ice sheet melt is likely to accelerate, and recognition of Rignot et al (2011) and Church & White (2011).

    I'm trying to recall the two researchers who demonstrated the acceleration in Antarctic melt around 2014. This year web searches find me papers by Konrad et al on Antarctic glacier grounding lines, and by Silvano et al on freshening by glacial meltwater and by IMBIE on tripling of Antarctic ice melt between 1992 and 2017.

    Moderator Response:

    [DB] Updated video link in post.  Thanks!

  39. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    I totally agree with nigelj here. I cannot picture kids being overwhelmed by this presentation. Frankly speaking, it's quite boring and not easy to grasp that way.

  40. Philippe Chantreau at 15:11 PM on 28 November 2018
    Discussing climate change on the net

    Art, that may be so but there is something about expanding effort where it will bring maximal return. 

    Scaddenp, point taken. Make sure you stay away from the strawberries too... :-)

  41. CO2 lags temperature

    The time lag is likely an illusion caused by an age date discrepancy between the ice and the gas trapped in the ice. The ice is snow before it is ice. The atmosphere is free to circulate to the bottom of the snow layer, so the gas is considerably younger than the ice it is imbedded in. Parrenin et al 2013 found that there is no lag between CO2 and the temperature changes when both are put on the same chronology.

    Synchronous Change of Atmospheric CO2 and Antarctic Temperature During the Last Deglacial Warming
    F. Parrenin et al.
    Science 339, 1060 (2013);
    DOI: 10.1126/science.1226368

  42. Discussing climate change on the net

    Philippe @ 9:  Air travel is not the most urgent emission source to tackle. Getting rid of coal burning and slowing deforestation would achieve far more than reducing air travel.

    It's an easy one to target however, given that 78% of air travel is a  recreational activity for relatively wealthy individuals. On the other hand, deforestation today is mostly ocurring in developing countries of Asia and South America, as a consequence of economic development. 

  43. Climate science comeback strategies: Al Gore said what?

    It's important to remember that the globe is not a homogenous whole, warming or cooling uniformly.  And that regional and seasonal differences exist, sometimes opposite in sign, over time.  So if the goal is to gain the best understanding of change over time, then I think that most would agree that the imperative is to use as many locations as possible using the most proxy types as possible, with the longest records possible.

    With that in mind, we can look at the last 1,700 years, (from the NCA4, Vol 1 from 2017), which covers the specific period in detail, but from a global perspective (and not confined to just winters):

    Last 1,700 years

    For additional perspective, we can look at global temperatures over the past 22,000 years (from Bruce Railsback's Fundamentals of Quaternary Science):

    Last 22,000 years

    So as we can see, global proxies offer the best context.

    A good summary of the present iteration of warming, from last week's released National Climate Assessment 2018, Vol. 2, from the Trump Administration:


    "Scientists have understood the fundamental physics of climate change for almost 200 years. In the 1850s, researchers demonstrated that carbon dioxide and other naturally occurring greenhouse gases in the atmosphere prevent some of the heat radiating from Earth’s surface from escaping to space: this is known as the greenhouse effect.

    This natural greenhouse effect warms the planet’s surface about 60°F above what it would be otherwise, creating a habitat suitable for life. Since the late 19th century, however, humans have released an increasing amount of greenhouse gases into the atmosphere through burning fossil fuels and, to a lesser extent, deforestation and land-use change. As a result, the atmospheric concentration of carbon dioxide, the largest contributor to human-caused warming, has increased by about 40% over the industrial era.

    This change has intensified the natural greenhouse effect, driving an increase in global surface temperatures and other widespread changes in Earth’s climate that are unprecedented in the history of modern civilization.

    Global climate is also influenced by natural factors that determine how much of the sun’s energy enters and leaves Earth’s atmosphere and by natural climate cycles that affect temperatures and weather patterns in the short term, especially regionally.

    However, the unambiguous long-term warming trend in global average temperature over the last century cannot be explained by natural factors alone.

    Greenhouse gas emissions from human activities are the only factors that can account for the observed warming over the last century; there are no credible alternative human or natural explanations supported by the observational evidence.

    Without human activities, the influence of natural factors alone would actually have had a slight cooling effect on global climate over the last 50 years."

  44. Climate science comeback strategies: Al Gore said what?

    JP66 @11 ,

    A/ Yes you are quite right, we should assess things coolly and logically, and not be swept away by a few tiny pieces of evidence (like cherry-picking a handful of leaves from a large forest).  There is a vast wealth of  evidence ~ consilient evidence ~ supporting the mainstream climate science . . . and there is almost none supporting the "denialist" viewpoint.   The denialists have rhetoric, and not much else.

    B/ As you are already aware, I'm sure, the hugely significant difference between the previous changes in temperature during the Holocene, and the present day global temperature . . . is that of rate of change.  At present, the surface temperature is climbing vertically like a Hornet on afterburners (excuse the mild hyperbole!).  And it is still climbing rapidly.   This is a vastly different situation from the slow & slight changes during the so-called Holocene Optimum and during the 5,000 years since then.

    C/ It's a good idea to step back and look at the bigger picture.  Coming out of the last glacial stage (and speaking in broad terms) there was a 10,000-year gradual rise of temperature of roughly 5 degreesC (and there was also a 1,000-year wiggle in the middle of that, named the Younger Dryas).  Then came a rather flat period of about 5,000 years, which some call the Holocene Optimum.   Following that, for 5,000 years has been a slow fall of temperature . . . until now.   Just as seen in the level Holocene Optimum, we also see during the declining past 5,000 years ~ various minor bumps and minor troughs (named the Roman Warm Period, the Medieval, the Little Ice Age, etcetera etcetera).   These small wiggles are very small, and came and went slowly (and they are so small in amplitude of rise/fall, that is is difficult to exactly define their start and finish).

    D/ The more important point is : what caused these previous minor wiggles during the Holocene?  There's only a limited number of candidates ~ minor variations in solar output (on a multi-decadal scale); occasional major volcanic activity; long-cycle oceanic overturning currents; etcetera.  Climate changes when something causes it to change.   It doesn't change for no reason.  (And I am sure you also know of the ultra-long cycle of Milankovitch.).   This is why the denialists are talking arrant nonsense, when they say that the recent warming [say from 1800 or 1850] is just "a rebound from the Little Ice Age" ~ they seem to forget that there must be an actual cause for change.

    JP66 . . . against the overall picture, the overall evidence . . . it is very difficult to find anything to get excited about, in fjord depths.  (If I have mis-read that, then I would be grateful if you would explain the significance.)

    JP66 , if you wish to question the general world data being correct/incorrect ~ you should read & discuss at a more appropriate thread.  [And a Spoiler Alert : the denialists have got that wrong as well!]

  45. Climate science comeback strategies: Al Gore said what?

    I am a climate fence sitter.  I like to think I read diligently on all sides.  Recently I came across a paper listed on a "denier" site and was wondering what the folks here had to say.  The conclusion of the study was quite clear:

    "The record shows a substantial and long-term warming during the Roman Warm Period (~350 BCE – 450 CE), followed by variable bottom water temperatures during the Dark Ages (~450 – 850 CE). The Viking Age/Medieval Climate Anomaly (~850 – 1350 CE) is also indicated by positive bottom water temperature anomalies, while the Little Ice Age (~1350 – 1850CE) is characterized by a long-term cooling with distinct multidecadal variability. When studying the Gullmar Fjord bottom
    water temperature record for the last 2500 years, it is interesting to note that the most recent warming of the 20th century does
    not stand out but appears to be comparable to both the Roman Warm Period and the MCA."

    Tracing winter temperatures over the last two millennia using a NE
    Atlantic coastal record
    Irina Polovodova Asteman1
    , Helena L. Filipsson 2
    , Kjell Nordberg 1 5
    1 Department of Marine Sciences, University of Gothenburg, Carl Skottbergsgata 22B, 41319 Gothenburg, Sweden
    2 Department of Geology, University of Lund, Sölvegatan 12, 22362 Lund, Sweden

    https://www.clim-past-discuss.net/cp-2017-160/cp-2017-160.pdf

    I realize the first and foremost rebuttal would be to say the report covers a subset of the globe and not the whole, but similar such studies show the same result in many areas of the globe.  Is the data incorrect?  Why are global average anomalies better suited to determining whether there is warming?

    Thank you for your input.

    Joe in NY

  46. Discussing climate change on the net

    I listen to talkback radio sometimes (please forgive me) and you hear the same characters phoning in with the same often identical comments in a certain type of style and usually related to climate change denial and small government ideology etcetera. I can't be sure, but it looks like they work for libertarian leaning lobby groups paying them to saturate the media. These people are organised, and to them the means justify the ends and they don't give a damn about standards of ethics, fair play or integrity. Cherrypicking is their middle name.

    The book Dark Money is very illuminating.

    I'm a free speech advocate, so I dont think climate scepticism should be banned as such, but I think repetitive propoganda, and wild claims should be culled out. Give people are change obviously, a warning, and don't be over zealous either as it alienates people on all sides of the debate and nobody will post comments. Bit of a balancing act I guess.

    A certain other climate website (won't name names) has a very slack moderation policy, and their website is a total mess imho full of repetitive  denialist propoganda, political rants,  and personal insults often among the warmists themselves, which is just embarrassing. It's counter productive, they are shooting themselves in the foot.

  47. Discussing climate change on the net

    Phillipe - that graph needs wider publicity. A lot of deniers see climate action as a threat to their car - justified to some extent - but understanding that coal electricity generation and agricultural are more important is helpful. However, the emission graph depends on your country. Here (NZ) it is roughly 50% transport / 50% agricultural (thermal electricity is a small player). When your economy is based on agriculture (particularly dairy with high methane emissions) and tourism (which needs air and car transport), it can be pretty sobering.

  48. Why does CO2 cause the Greenhouse Effect?! | Climate Chemistry

    I hugely respect Climate Adam, and realise hes trying to make science fun, but this video is a trainwreck and just so childish and distracting. A few wiggles of CO2 molecules on a diagram would have been more informative, and taken a fraction of the time.  Give them smiley faces, if you want to make it fun.

    How do we get from measuring the level of energy absorption by the molecule to calculating a change in global temperature? It would be interesting to see the basic maths and physics but kept at a level the average person in the street can relate to.

  49. Discussing climate change on the net

    "Rebukes that this constitutes censorship or infringement of their rights to free speech can be safely ignored as there are many other websites - perhaps even their very own Facebook page! - where they can post whatever they want. And if they don't get this message, you can always show them the door via XKCD's neat cartoon:"

    When you look at the amount of money from individuals like the Koch brothers and corporations like Exxon Mobil, I don't see how climate change denial can be considered free speech in any sense. And more and more this denial is being funded in the same way drug cartels and terrorist groups move money around to avoid discovery.

    "Dark Money" Funds Climate Change Denial Effort

    "The study, by Drexel University environmental sociologist Robert Brulle, is the first academic effort to probe the organizational underpinnings and funding behind the climate denial movement.

    It found that the amount of money flowing through third-party, pass-through foundations like DonorsTrust and Donors Capital, whose funding cannot be traced, has risen dramatically over the past five years.

    In all, 140 foundations funneled $558 million to almost 100 climate denial organizations from 2003 to 2010."

    Climate change denial has nothing to do with evidence and fair comment, it is essentially deceptive advertizing. And follows on from the same kind of deceptive campaign to prevent action in the public interest that tobacco corporations funded for years.

    The denial industry

    'So the fight against a ban on passive smoking had to be associated with other people and other issues. Philip Morris, APCO said, needed to create the impression of a "grassroots" movement - one that had been formed spontaneously by concerned citizens to fight "overregulation". It should portray the danger of tobacco smoke as just one "unfounded fear" among others, such as concerns about pesticides and cellphones. APCO proposed to set up "a national coalition intended to educate the media, public officials and the public about the dangers of 'junk science'. Coalition will address credibility of government's scientific studies, risk-assessment techniques and misuse of tax dollars ... Upon formation of Coalition, key leaders will begin media outreach, eg editorial board tours, opinion articles, and brief elected officials in selected states."'

    When comments from such sources are removed and people who are quite likely being paid to disseminate false information are banned it is in all our interests.

    Climate change is becoming more destructive and deadly every year, the wildfires in California now are just the opening stage of this catastrophic process. 

    Sites like Skeptical Science and those who are involved in presenting the real story based on clear evidence are working in the interests of our entire species against what is now obviously an existential threat.

  50. Discussing climate change on the net

    Art Vandelay @8

    Yes effective top down action requires the majority are comfortable with it, however the case of the French protesting against fuel prices is probably not an ideal or representative example. Refer article here. Its due to a combination of higher prices for fuel imports and extra taxes one of them being a carbon tax, so its the combination that has possibly pushed them into protesting. And the French protest about anything, believe me while other countries do not.

    The government indeed obviously needs to tread carefully with taxes. It looks like Macron chose the wrong time just when petrol prices are at a peak, which was obviously going to be temporary so he could have waited.

    In addition, the french carbon tax is not a tax and dividend scheme, so is quite harsh on consumers. The tax goes into funding a range of things, not just renewable energy. 

    There's no escaping the need for a top down solution. Individuals cant build electricty grids and individuals are reluctant to reduce carbon footprints, possibly because they dont see many other people doing the same, hence the need for top down solutions of various kinds to get things moving. When people see some action they are likely to be more personally motivated.

    Some people might indeed tend to say its governments problem, but I think the vast majority have enough sense to realise mitigation requires both electricity grids and personal changes in behaviour of various types.

    Of course its important to show there are several things people can do to make a difference without waiting on governments, and which can only be driven by consumers,  like reducing meat consumption and trying to be more economical with energy use. There are multiple benefits in such things as you also alluded to regarding renewable energy. Perhaps this needs to be used more in education campaigns.

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