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

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Comments 8951 to 9000:

  1. CO2 was higher in the past

    nyood @92,

    (1a) To present a value for CO2 forcing without providing evidential support is not axiomatic, either in the sense of it being self-evident or (probably in the sense you intend) unquestioningly-evident. The evidence can be presented should you so wish and, uncontroversially beyond-question, it is correct.

    You yourself present @92 an unsupported evaluation of CO2 forcing, providing a maximum value which appears novel and controversial in the extreme. You fail to present any evidential support which in the circumstance is turning this discussion into a pantomime. Perhaps you could correct the untenable postion you create for yourself by providing that missing evidence.

    (1b) Your confused statements regarding HHE/LPC appear to contrdict the geographical situation as commonly understood, in that the "Land mass" Gondwawa sits static over the "Polar Circle" throughtout this period. You need to consider how it is your LPC appears then disappears within this period when the contition you say causes LPC remains unchanging?

    (2) Your cut-&-paste from the Schwark & Bauersachs slides appears particularly inept as support for your assertion "in fact it doubts CO2 as a driver." If you, for instance, examine Slide 11 you will see your assertion is fundamentally contradicted.

    (3) Here you really do dip into uncomprehensibility. Do note that the Schwark & Bauersachs slides do not ever say CO2 dropped to present atmospheric levels 400-odd million years ago. The statement you misread from Slide 23 says purely that CO2 varied "between 8-16 x PAL and near PAL." The value 1500ppm can be taken from their Slide 11.

    (4) If it is not land at the polar circle that creates your LPC condition; if it is ice-covered land, you do then reqire to explain the forcing that allows the growth/shrinkage of that ice. And in doing so, your theory now lacking the tectonic element, do consider that you are now describing a climate feedback not a climate forcing.

  2. CO2 was higher in the past

    Nyood

    continuing with my itemized points of post #90 and your itemized replies in post #92 (subsection) :-

    (A)  Your quote: <" ... can not apply CO2 with a clear value (uncertainty)">

    Here, too much is lost in translation.  You will need to make a re-translation of your idea into English, to achieve a meaningful statement.   Secondly: "Saturation" is invalid, and "Lindzen" is (often) invalid.

    (B)  <"(B) same as (A)">  does not make sense as a reply.

    (C)   <"observational evidence support my theory today">   Yes, but only in part. The full picture of observational evidence (on CO2 greenhouse) renders your theory invalid [ungueltig].

    (D)  Geological evidence supports your theory only in part.  The full picture of geological evidence renders your theory invalid.

    Nyood ,

    in my post #90 , the final and most important question (for you) was: "why do you choose to ignore evidence?"  Note the word choose  [waehlen].

    You have not answered that question.  Please do so, carefully and thoughtfully.  It requires using insight [Einblick; Selbstverstaendnis].

  3. Philippe Chantreau at 10:04 AM on 5 November 2019
    CO2 was higher in the past

    Nyood: "I state that CO2 forcing is max 1°C, reaching saturation with roughly PAL levels, pretty much always or already."

    Earlier you said "The total climate forcing from 6000ppm CO2 is very roughly 40Wm^-2"

    That would suggest then that a 40w/sq.m forcing would produce only a 1 deg C change? What published work is this based on? How did you get the 40 W/sq.m value?

    What is your basis for claiming "reaching saturation with roughly PAL levels, pretty much always or already."

    Current forcings are calculated from radiative physics, Iacono and Clough, and many others have worked on that. So what do you mean by "CO2 forcings as assumed (too high)"? AFAIK, these forcings are not assumed, they are calculated on the basis of the physical properties of the gas.

    Moderator Response:

    [PS] "And these forcings are not assumed, they are calculated". And directly observed https://www.nature.com/articles/nature14240. ie observations match theory. By contrast we are seeing wild claims from Nyood with no supporting evidence.

    Argument about CO2 saturation belong in this thread. If nyood wants to make that claim, then present the evidence in that thread please.

  4. CSLDF: Here’s How Science Has Suffered During the First 1,000 Days of Trump

    Thanks, jabell. I think we need to hire you! ("hire" not implying actual salary :-) )

  5. CO2 was higher in the past

    "(1) The total climate forcing from 6000ppm CO2 is very roughly 40Wm^-2. There is no evidence
    to suggest that climate was impacted by such forcings (from any source) during the Ordovician."

    (1) The first sentence is axiomaticly using an estimated forcing of CO2 and therefore is a statement, though the consequences you state are true (none).
    I state that CO2 forcing is max 1°C, reaching saturation with roughly PAL levels, pretty much always or already.

    The Second sentence is true, the forcings that Do determine climate Temperature (T) are the two equilibrium forces
    hothouse effect (HHE) and high landmass ratio within polar circles (LPC).
    The faint sun paradox (FSP) underlines the strength and dominance of the terrestial forcings by allowing
    the orrdovician-silurian events, HHE - LPC - HHE, to happen within the same T amplitude of all compareable HHE and LPC events untill today.
    Neglecting CO2 and reducing the FPS or -4% TPI, in its forcings.

    On top of that you devaluate some of your own arguments brought up in the coming sections. According to (1) you do not allow yourself any comparison from there on.

     

    "(2) According to your cited reference (slides 11 & 14), the period with elevated CO2 significantly above 4000ppm
    coincides with the Katian, a period of warming."

    (2)This sentence has no expressiveness. HHE is happening anyways before and after the LPC.
    The Katian documents the late transition state towards an LPC, in fact it doubts CO2 as a driver.
    The discrepancy between assumed CO2 forcing and T is underlined by the general high CO2 level in the atmosphere, the planet will reach a glaciation from here on, to develop extreme ice shields despite CO2 levels this high. The FPS is solved as mentioned.
    Furthermore forces mentioned in the Schwarck study explain the Katian warming already:
    " Bodaevent:
    Continental Flood Basalt Province.Alternatively to a bolide impact, LIPs have been postulated as warming triggers."

    The forcing here that matters is Ice albedo reduction due to dust and ashes.
    We can see this again when younger impacts and events causie warming rather then cooling.
    An accumulation of dust and ashes at the poles are the result of a rather quickly cleanse of the atmosphere.

     

    "(3) The period following the Katian sees falling CO2 and falling temperature.
    The period of high glaciation during the Himantian sees CO2 estimates
    dropping to perhaps 1500ppm. Relative to our recent ice ages with 180ppm CO2,
    the Himantian CO2 forcing would thus be perhaps +11Wm^-2 while the relative solar forcing would be -8Wm^-2."

    (3) "dropping to perhaps 1500ppm". The Schwarck study claims PAL up to x6 till x20. Please specify "perhaps"
    and clarify why it is not PAL but minimum PAL x3 according to you. Where are Schwank et.al wrong ?

    Reminding here that the level of CO2 does not matter in the first place unless it is below PAL (max -1°C), using my axioms.

    Again you apply axiomatical values, which are not needed to explain temperatures, you are still using the FSP as a theory support, or to bring it in an equilibrium with
    CO2 forcing, by trying to "ramp up" CO2 to a minimum of 1500ppm. Ironically this opposites many attempts
    that try to lower CO2 to explain why a glaciation happens, despite ~6000ppm before and after the glaciation, in the first place. These views higlight the needs to explain CO2 forcings as assumed (too high).

     

    "(4) Your assertion @89 is that the major forcing of climate is the tectonic positioning of land over polar regions.
    Yet there was such land over polar regions throughout the Ordovician when these great swings of climate appear suggesting
    the climate was being forced by entirely different mechnisms.

    I would therefore suggest you have failed to provide any support for your assertion "CO2 is no driver at all." "

    (4)This is partly true, as strong as it is the Ice has to build up, which happens very quickly in the hirnation, after the Bodaevent.
    The middle to late ordovician is in transition, the continental drift towards the pole is remarkable.
    Which is documented with the Silurian:

    Ordovizium

    Silur

    Furthermore one has to take in account the varying lengths of time periods. The ordovician has been added historicaly,
    it was included in the silurian before, therefore this interesting periods are "staunched".

    Antarctica shows a trend towards having a "drop back" to the south pole, mentioned in the devonian and possible in the jurassic.
    Maybe this happened here too and we need more accurate paleogeorgraphic data.

     

    Answering two other comments here made by other users:

    89.Moderator response:

    "[PS] This is heading way into sloganeering territory. You are selecting only observations that support your ideas and ignoring completely all others. Science does not operate that like.
    You cannot ignore measured increase in downwelling radiation, conservation of energy, nor explain past climate change with hand-wavy statements that violate physics.
    If you have a theory that can match all observations, simpler and with better precision than current theory and concordant with laws of physics then by all means publish. Meanwhile,
    current climate theory is the one that matches Occams razor. No more half-baked sophistry please."

    My theory already has a better explanation with its radical attempt, that is the whole point. This is not "sloganeering" it is just a very radical attempt so it asks for situations where we have evidence that show CO2 as a significant driver, relating to topic.
    I understand that my radical attempt makes it easy for me but i have to insist on the fairness that i am allowed to show that radical assumptions that i made, make more sense then your axiomatical assumptions.
    There is the inherit problem that we eventualy go off topic but i have to ask you at this point which laws and forcings (radiation, energy conservation) are ignored by me in which way ?
    I ignore factors as far as they allow me, hence ockham.
    I insinuate that your axioms make less sence then mine. Your critisicsm lacks precission at this stage, when it comes to why my radical assumptions are not allowed and where they are not concordant with laws of physics.

     

     

    90. Eclectic:

    "Nyood, the importance of CO2 as a driver of climate, is supported by (A) theoretical calculations [Arrhenius and later scientists]; is supported by (B) experimental evidence; is supported by
    (C) observational evidence; and is supported by (D) geological evidence. In other words, the mainstream science developed during the past 200 years.

    The principle of Occam's Razor is a often a helpful guide to thinking : it is not in itself evidence and it is not in itself a method of proof.

    Ockham (or Occam) did not support the cutting off or ignoring of evidence. Newton and Einstein did not ignore evidence. Nyood, why do you choose to ignore evidence?"

    (A) Arrhenius,Planck Feldmann et.al give a frame, it is known that we can not apply CO2 with a clear value (uncertainty). This leads to a Saturation and or Lindzen et.al and therefore inevitable offtopic, as much as i am willing to discuss it.

    (B) same as (A)

    (C) I clame that observational evidence support my theory today: Dramatic CO2 increase with a moderate warming trend. My initial post was rightfully snipped of modern time references as offtopic.

    (D) Geological evidence is the core of the LPC theory.

    Moderator Response:

    [DB] Off-topic, sloganeering and inflammatory snipped.

    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, off-topic posts, ignores the refutations of others (sloganeering) or simply makes things up. We really appreciate people's cooperation in abiding by the Comments Policy, which is largely responsible for the quality of this site.  The point of commenting is to further the understanding of the science, using credible evidence and citations to credible sources.  Much of what you are attempting to do would be better-placed on other threads (many exist).  Blanket asserting that the greenhouse effect is not well-documented, well-researched and well-understood is an own-goal and a waste of everyone's time.
     
    Finally, please understand that moderation policies are not open for discussion (complaining about moderation that everyone else has little to no issues with rather than simply adhering to the Comments Policy likewise wastes everyone's time).  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.

  6. One Planet Only Forever at 04:59 AM on 5 November 2019
    It's methane

    Estoma,

    I hope that the development of the Sustainable Development Goals improve awareness and understanding of how fatally flawed the developed ways of living are, including but not limited to the problem of methane resulting from human activities.

    There are many examples of undeniably 'unsustainable and harmful developments'. And in each major case there is evidence of damaging resistance to correction.

    The most glaring example of harmful developments and resistance to correction is fossil fuel use. Climate science has unwittingly produced the powerful proof of how fatally flawed the developed socioeconomic-political systems are.

    Hopefully the Climate Science case will be a Tipping-point regarding the awareness and understanding of the need for Governing/Limiting what is allowed to happen to ensure that the results will be sustainable improvements for humanity. Ethical governing/limiting to achieve and improve the Sustainable Development Goals, including limits on merthane production, is undeniably required when people pursue Personal Benefit or Status relative to Others, especially in Competitions for Popularity and Profit.

  7. Climate Change: The 40 Year Delay Between Cause and Effect

    kootzie @66,

    The paper you reference Zickfeld & Herrington (2015) 'The time lag between a carbon dioxide emission and maximum warming increases with the size of the emission' adds to the findings of Ricke & Caldeira (2014) 'Maximum warming occurs about one decade after a carbon dioxide emission' by modelling different sizes of CO2 impulse from 100Gt(C) to 5000Gt(C) while Ricke & Caldeira consider just the one size of impulse - 100Gt(C). (Note that we have emitted nearly 700Gt(C) and are today adding to that total at a little over 11Gt(C)/year.) Within such models of a CO2 impulse, the warming from the CO2 forcing is impacted by the drawdown of CO2 from the atmosphere which reduces the resulting CO2 forcing. Were we to stop our CO2 emissions, reduce that 11Gt/yr to zero, we should expect a similar rapid response to this end of emissions with atmospheric CO2 levels falling away (initially quite quickly) and temperature increases replaced by roughly constant temperature.

    Be sure not to confuse these 'impulse' response times with the response to an increase in atmospheric CO2 levels in which the increased CO2 level (and associated forcings) is maintained in coming decades/centuries. Such projections are quite common (they re used to calculate ECS) and show perhaps 40% of the warming within the first decade followed by a long slow warming lasting into the following century.

  8. Climate Change: The 40 Year Delay Between Cause and Effect

    I just came across this paper which indicates a much shorter response time of 10ish years for the full effect to be observed with that tome-reaponse being dependant on the size of the impulse

    https://iopscience.iop.org/article/10.1088/1748-9326/10/3/031001

  9. CSLDF: Here’s How Science Has Suffered During the First 1,000 Days of Trump

    Please note that the second pie chart repeats the first, although correctly titled from the original source.

  10. It's methane

    One Planet Only Forever, thank you for your interesting reply.  There hasn't ever been a time when humans haven't advertised to the detrament of society.  I fear that by the time we come to the realization that it might be to little to late.

  11. Ynyslas, western Wales – a place made by climate change

    Lookds like I'll be buying this book. Spent many field trips for my degree, forced to go to the beach at Ynyslas (and one surveying Borth bog). :-)

    Fascinating location with many rare features.

  12. CO2 was higher in the past

    Nyood @89,

    You ask that we roll back to your initial comment here, up-thread  @83 where you begin by quoting from a talk by Schwark & Bauersachs [slides] quoting from its summary:-

    "Massive perturbations of the atmospheric and hydrospheric carbon cycle occurred with CO2 concentration varying between 8-16 x PAL and near PAL over short periods of time." (PAL = Present Atmospheric Level.)

    From this you conclude the following:-

    "This is quite remarkable, it tells us that a glaciation is capable to absorb even CO2 ammounts of 6000ppm. It does not matter how high CO2 Levels are, a glaciation will happen when the following event occurs:"

    Your conclusion is incorrect on a number of levels.

    (1) The total climate forcing from 6000ppm CO2 is very roughly 40Wm^-2. There is no evidence to suggest that climate was impacted by such forcings (from any source) during the Ordovician.

    (2) According to your cited reference (slides 11 & 14), the period with elevated CO2 significantly above 4000ppm coincides with the Katian, a period of warming.

    (3) The period following the Katian sees falling CO2 and falling temperature. The period of high glaciation during the Himantian sees CO2 estimates dropping to perhaps 1500ppm. Relative to our recent ice ages with 180ppm CO2, the Himantian CO2 forcing would thus be perhaps +11Wm^-2 while the relative solar forcing would be -8Wm^-2.

    (4) Your assertion @89 is that the major forcing of climate is the tectonic positioning of land over polar regions. Yet there was such land over polar regions throughout the Ordovician when these great swings of climate appear suggesting the climate was being forced by entirely different mechnisms.

    I would therefore suggest you have failed to provide any support for your assertion "CO2 is no driver at all."

  13. CSLDF: Here’s How Science Has Suffered During the First 1,000 Days of Trump

    And the administrations attacks on science have implications that cause even more trouble for example here: NOAA’s chief scientist will investigate why agency backed Trump over its experts on Dorian, email shows

  14. CO2 was higher in the past

    Nyood, the importance of CO2 as a driver of climate, is supported by (A) theoretical calculations [Arrhenius and later scientists]; is supported by (B) experimental evidence; is supported by (C) observational evidence; and is supported by (D) geological evidence.  In other words, the mainstream science developed during the past 200 years.

    The principle of Occam's Razor is a often a helpful guide to thinking : it is not in itself evidence and it is not in itself a method of proof.

    Ockham (or Occam) did not support the cutting off or ignoring of evidence.  Newton and Einstein did not ignore evidence.   Nyood, why do you choose to ignore evidence?

  15. CO2 was higher in the past

    Moderator Response:

    "[DB] Please re-read the entire post before commenting. As the post notes, CO2 is not the only driver of climate.
    No climate scientist makes any such assertion. So you tilt at windmills of your own building."

    There seems to be a  missunderstanding here, apologies for my bad writing in my initial post if this is the reason for the confusion.

    I do not contest that or if CO2 is a sole climate driver. I state that CO2 is no driver at all.

    So let me try to give a summary here again:

    The theory is radical. The two equilibriums glacial period (high landmass ratio within polar circles,high LPC) vs Hot House Effect (HHE),
    are that dominat, they neglect all other drivers. low LPC will result in a HHE no matter what.
    General backround HHE forcing is so effective, all other factors do not matter, the warming rate is always rapid, the transition is always within 100 mio years.
    The second largest factors that still have significant forcing are all factors that relate to albedo foremost ice albedo (dust, ashes, sea level).

    Following Orckham we have several situations where neglecting CO2 makes way more sense than assuming any significant forcing.

    Ordovician high disparity of CO2 and T. Carboniferus CO2 drop way before temperature (T) drop. Jurassic CO2-T meeting. Cretaceous all time highest discrepancy.

    TempCo2History to

    The situations where an explanation for CO2 is needed to justify its assumed forcings, is simply and higly objected by Orckham`s razorblade principle.

    So politely i have to say dito: Please re-read my initial post.

    Moderator Response:

    [PS] This is heading way into sloganeering territory. You are selecting only observations that support your ideas and ignoring completely all others. Science does not operate that like. You cannot ignore measured increase in downwelling radiation, conservation of energy, nor explain past climate change with hand-wavy statements that violate physics. If you have a theory that can match all observations, simpler and with better precision than current theory and concordant with laws of physics then by all means publish. Meanwhile, current climate theory is the one that matches Occams razor. No more half-baked sophistry please.

  16. One Planet Only Forever at 02:28 AM on 4 November 2019
    It's methane

    Estoma@47,

    As a pursuer of improved awareness and understanding, and the application of that constant learning to help develop lasting improvements for all of humanity far far into the future (this planet should be habitable for about 1 billion years), my understanding is that what matters regarding food is:

    • the way that food is produced
    • the amount of a type of food that is consumed
    • the amount of consumption of non-nutritious stuff
    • the ability of everyone to get adequate nutrition (and healthy water and healthy air)

    The Sustainable Development Goals provide a robustly developed comprehensive basis for evaluating the acceptability of: what has developed, the required types of new developments, and corrections that are required.

    And pursuing improved awareness and understanding makes it clear that competition for impressions of superiority measured by popularity and profit have driven the development, and resistance to correction of, the following harmful unsustainable food production and consumption results:

    • Desires for unhealthy harmful unsustainable Diets. Many people in supposedly more advanced nations develop a liking for eating in ways that produce many understandably harmful results.
    • Desires to over-consume, particularly the over-consumption of meat. The body can only process the protein from about 4 oz of meat in a meal. And a healthy diet does not require that 4 oz helping of meat in every meal.
    • The preponderance of over-consumption of non-nutritious stuff.
    • The starvation and malnutrition of portions of the population which is a result of competitions for popularity and profit, including the way people are driven to not be as aware and understanding as they should and could be.

    A major driver of harmful unsustainable developments is successful disinformation and misinformation marketing (Misleading storytelling). That success is due to people developing an 'interest in trying to Win in harmful ultimately unsustainable ways', combined with developing an easily impressed population that resists improving understanding when that awareness and understanding would require changing developed popular and profitable activity and related perceptions of prosperity or opportunity for personal benefit.

    The supposedly more advanced nations have not succeeded at developing populations that pursue improved awareness and understanding. What they have developed is populations easily tempted to be passionately triggered by misleading marketing developed and delivered by pursuers of harmful and unsustainable popularity or profit.

    And Social Media and News Media pursuing popularity and profit can be seen to be publishing a lot of misleading stories that do not help improve the awareness and understanding of what is really going on regarding food.

    The need to correct many things regarding food production and consumption does not mean 'eliminating those things'. However, the fossil fuel burning related to food does indeed need to be ended, not just be reduced.

    With that understanding in mind your concerns are warranted. Reread the article. It will likely become obvious how much of it is sensationalist extremist correction resistant storytelling trying to defend the 'harmful unsustainable creations developed by competition for impressions of superiority measured by popularity and profit' rather than 'helpfulness to developing a sustainable improving future for all of humanity'.

    Many popular and profitable developments of competition for status do indeed need to be corrected to develop a sustainable improving future for all of humanity. Reducing climate change impacts is a major, but not exclusive, part of the required corrections. Human activities that create accumulating negative impacts, like the use of fossil fuels need to be ended. Other changes of human activity that would reduce GHG levels in the atmosphere are also helpful, but do not need to be taken to the extreme correction (the elimination of them) that is required regarding fossil fuel use.

  17. It's methane

    Just read the USA today opinion article entitled, "Let them eat steak: Hold the shame, red meat is not bad for you or climate change."

    https://www.yahoo.com/news/let-them-eat-steak-hold-090012002.html

    My concern was not over whether eating meat was unhealthy or not.  It was the claim that it didn't effect AGW because livestock only account for a 2,6% increase in CHG's.  I checked a 2017 study in PNAS which verified the 2.6% reduction in greenhouse gases due to other factors ivolved in increasing the amount of plant production. 

    https://www.pnas.org/content/114/48/E10301

    The thing for me is; are we bound to keep producing plant based food under the methods were producing it today?  Do we have to keep producing plant based food with the same CHG intensity that were presently producing it at?  My family grows 16 acres of organically grown vegetables in field and high tunnels but I'm skeptical that it can be the solution for feeding the world at this point in time.  

    The study also concludes, "the removal of animals resulted in diets that are nonviable in the long or short term to support the nutritional needs of the US population without nutrient supplementation."  My wife and son eat absolutley no meat and I'm what I like to term a "social caravore."  If your serving meat I'll partake but that's the extent of my fleash eating activity.  I'm 72 and my wife is 69 and my son is 38.  Last year when I told my doctor that unlike my friends and I've never had a stress test or an EKG.  She ordered up an EKG.  The tech came in and did the test.  About 15 minutes he popped her head in the door and said, "Your an athlete, arn't you?" to which I replied, I'm a farmer.  I'm not sure why our diets would need suplamention.  I'm concerned about what I'm reading.

  18. CO2 was higher in the past

    Nyood @87 , my apologies to you, for my speaking overly-briefly about LIP eruptions.

    My example of the Siberian Traps event demonstrated the vast release of CO2 and consequent high temperature rise on Earth.  The Deccan Traps event was smaller in effect, and also was complicated by the cooling effect of the Chicxulub asteroid impact.

    You are quite right to say LIP events can have a transient cooling effect from the venting of sulphate & other aerosols . . . and also in the much longer term, the exposed silicate rock does gradually draw down the atmospheric CO2 (and hence the lower CO2 will lead to a global cooling, relative to what had gone before).

    My essential point with respect to Antarctica, was that a future LIP eruption could be of enough size to produce a major boost in atmospheric CO2 and consequently a major temperature rise for a lengthy period ~ sufficient to melt away the huge Antarctic ice sheet.

    We must hope that a major LIP eruption will not occur, for its result could be catastrophic.

    The question of Ordovician temperatures and glaciation is a difficult one, for the timing of events & CO2 changes rests presently on low-resolution data.   For the relevance to the climate of the modern age, we must rely heavily on the lessons from basic physics.

    Moderator Response:

    [JH] Links activated.

    For future reference, when you include a link in a post, please activate it by using the "Insert/Edit Link" feature of the Edit Box.

  19. CO2 was higher in the past

    "There are two scenarios where Antarctic ice will disappear:
    - (A) the very long term (many millions of years)
    as the solar output continues its gradual increase, and
    (B) an unexpected Large Igneous Province eruption of CO2,
    such as the Siberian or Deccan events. In either of these
    circumstances, the South Polar ice would disappear, even if
    Antarctica did not move from its present polar position."

    (A) This is true the sun will warm for a billion years. If and
    when this will melt the poles i do not want to discuss
    here,interesting question towards the HHE Hot House Equilibrium though.

    (B) The Deccan Traps caused cooling. wikiDeccan
    The polar ice would not disappear, you just make an assumption here. The ordovician
    tells us the opposite: Even with levels of 6000ppm a glaciation occurs.
    You miss the start of my original post: "This is quite remarkable, it tells us
    that a glaciation is capable to ABSORB even CO2 ammounts of 6000ppm"
    and you ignore the core of my LPC theory, basicly by just saying "it is so, Antarctica would melt"

    Please be more carefull with prospective criticism, you can try to go on and find
    other arguments pro CO2, like the PETM or the permian-triassic in the past to stay on topic.
    Or you can fight my theory and i give you a hint here: i mentioned the "triassic north pole paradox".

    "The present day crisis involves the small-magnitude warming which will displace around 200 millon people
    as sea level rise approaches 1 metre [Kulp & Strauss, 2019]. And probably a much greater size of refugee problem,
    coming from storm surge, land salination, and other agricultural adverse effects
    (including low-humidity and high-humidity heat waves]."

    What you are doing here is seen very often, you let someone speak for you.
    I would have to read the study, check the sources, check the context
    and then come back to you. You have to express your thoughts yourself and use studies to back up your argumentation.

    First of all what we are seeing here is the common axiomatical acception that CO2 plays a strong role, i would have to argue with Strauss
    and confront him with my LPC theory first.
    You can check accepted sources like NASA on Sea rise. It will never be that quick that men will not adept let alone react in time.
    Furthermore since i see the increase as natural, there is no point to try to change it.

    Moderator Response:

    [DB]  Please re-read the entire post before commenting.  As the post notes, CO2 is not the only driver of climate.  No climate scientist makes any such assertion.  So you tilt at windmills of your own building.

    Relevant to this discussion:

    "The evolution of Earth’s climate on geological timescales is largely driven by variations in the magnitude of total solar irradiance (TSI) and changes in the greenhouse gas content of the atmosphere.

    Here we show that the slow ∼50 Wm−2 increase in TSI over the last ∼420 million years (an increase of ∼9 Wm−2 of radiative forcing) was almost completely negated by a long-term decline in atmospheric CO2. This was likely due to the silicate weathering-negative feedback and the expansion of land plants that together ensured Earth’s long-term habitability.

    Humanity’s fossil-fuel use, if unabated, risks taking us, by the middle of the twenty-first century, to values of CO2 not seen since the early Eocene (50 million years ago).

    If CO2 continues to rise further into the twenty-third century, then the associated large increase in radiative forcing, and how the Earth system would respond, would likely be without geological precedent in the last half a billion years."

    Foster et al 2017 - Future climate forcing potentially without precedent in the last 420 million years

    Foster Figure 2

     

    Off-topic and inflammatory snipped.

  20. CO2 was higher in the past

    Nyood @85 , thank you for that comment: <"The only thing that will cause earth to leave the glacial period of the cenozoic is when Antarctica will move away from the south pole once again.">

    I think it is not controversial that Earth will remain in an ice age for a very long time (ice age defined as Earth having substantial ice at one or both poles).

    Even during the warm Eemian period, there was polar ice in the Scandinavian region (at least) plus the huge amount of land ice on the Antarctic continent.

    A small rise in temperature (from today's) might fully melt Greenland ~ but that would likely take  >1000 years.   Still, most of the East Antarctica ice sheet will survive.

    There are two scenarios where Antarctic ice will disappear:-  (A) the very long term (many millions of years) as the solar output continues its gradual increase, and (B) an unexpected Large Igneous Province eruption of CO2, such as the Siberian or Deccan events.  In either of these circumstances, the South Polar ice would disappear, even if Antarctica did not move from its present polar position.

    The present day crisis involves the small-magnitude warming which will displace around 200 millon people as sea level rise approaches 1 metre [Kulp & Strauss, 2019].  And probably a much greater size of refugee problem, coming from storm surge, land salination, and other agricultural adverse effects (including low-humidity and high-humidity heat waves].

    All this, within the lifetime of children born in 2019.

  21. CO2 was higher in the past

    Ok i will try to be more structured with future comments.

    You seem to confuse cambrian and precambrian in your criticism. The precambrian is a superaeon before the cambrian era, also called Cryptozoic. Therefore i was talking about the maximum value of a 25% dimmer sun, One of the snowball effects i refered too happend very early in the hadian, the younger double snowball event happen way closer to the cambrian.

    <a href="https://en.wikipedia.org/wiki/Geologic_time_scale"> WikiGeoTime</a>

    Yes my conclusion statement stays:

    The only thing that will cause earth to leave the glacial period of the cenozoic is when Antarctica will move away from the south pole once again.

  22. CO2 was higher in the past

    Nyood,

    your presentation of items is jumbled or durcheinander, as the Germans say.  It would be helpful if you could make a succinct summary of the information you wish to convey for this particular thread (and not a Gish Gallop of disparate items belonging to many different threads).

    Please note that the Ordovician sun was about 3% fainter than the modern sun.  The "25% lesser sun" belongs to the very early life of the planet Earth.

    You seem to be suggesting that atmospheric CO2 has no effect on planetary surface temperature.  But that goes against all modern science ~ but still, if you are serious in stating it, then you should present your argument in the appropriate thread here in this SkS website.

  23. CO2 was higher in the past

    According to this recent study we have a way more accurate view on this issue now:

    Schwark2019

    In the Hirnation Event Summary:

    "Massive perturbations of the atmospheric and hydrosphericcarbon cycle occurred with CO2concentration varying between 8-16 x PAL and near PAL over short periods of time." PAL means Present Atmospheric Level.

    This is quite remarkable, it tells us that a glaciation is capable to absorb even CO2 ammounts of 6000ppm. It does not matter how high CO2 Levels are, a glaciation will happen when the following event occurs:

    Sufficent Landmasses within the Polar Circles (LPC).

    Going through all time periods, we can show how decisive landmasses at the polar circles are. Note that the polar circles represent a very narrow area at the north and south borders on these pictures. Greenland todayis a good example as it forms the only northern ice shield, mainly being within the arctic circle, while edging Canada and Russia are not inland iced.

    Cambrian warm period, Landmasses in the Polar Circles (LPC): 0%-10%

    Cambrian

    Ordovician hirnantion glacial event antarctic LPC 100%:

    HirnantionEvent

    Silurian cold LPC antarctica 90%:

    Silur

    Devonian warming LPC 10% - 40% :

    Devon

    Carboniferus glaciation, Continents drop back to the south pole antarctic LPC: 90%-100%

    Karbon

    Permian Cold with late permian transition towards mesozoic Pangea arctic LPC 80% - 100%:

    Perm

    Triassic warming, antarctic PLC 10%-20%, arctic PLC 70% to 90%. only Southern PLC decisive? Arctic inland ice forming reversed with the jurassic? Triassic north pole contradicton.

    Trias

    Jurassic, Landmasses moved away from the arctic cycle. arctic LPC 10%-20%. antarctic LPC 5%-10%.

    Jura

    Cretateous, sea level rise noticeable, deglaciation at its maximum, transition to upcoming glacial period, Antarctica moving south. Antarctic LPC 80%-100%:

    Kreide

    Today, Cenozoic glacial period Antarctica resting at the pole once again. Greenland LPC 10% -20%, Antarctica 90%-100% LPC.

    With an Ockham attempt i want to make 3 main arguments on why CO2 is not needed and not likely to play any thermal role at all:

    1.Faint Sun Paradox,Snowball Earth and the Hot House Equilibrium.

    The faint sun paradox is not a paradox. It is another evidence of how strong the terrestial force Ice Albedo is and therefore again the continental distribution.

    Even with a 25% lesser sun, Oceans occur,hence the term "paradox".While precambrian snowball effects due to a supercontinent at the south pole, demonstrate the lesser sun effect.

    The so called paradox underlines the trumendos forcings of Albedo and it describes the fundamental drive towards a hot house equilibrium whenever the poles are uncovered by land.

    This Basic heating Trend that is strong enough to even compensate the faint sun paradox puts CO2 further away from having any thermal influence. This basic heat trend is documented by all the terminations of glacial epoches and even more so in the precambrian, with a barrier where no more heating seems possible.

    So we keep in mind that we have a Glacial period during the ordovician to the early silurian, with Co2 levels around up to 6000ppm.

    2. Carboniferous CO2 Levels

    The carboniferous marks the point where the flora takes an increased influence on CO2 levels.

    T°Co2overview

    The late devonian till the middle carboniferus show how CO2 is absorbed while temperatur takes ~90 mio years to "follow".The reason temperature goes down is as usual, the continental drift towards the south pole.

    What we eventualy see is a double decline in CO2.

    The jurassic-cretaceous meeting of CO2 and temperature speaks for itself.

    3. Today,GISS and an estimated CO2 sensitivity of 1,5°C

    The uncertenty itself on the CO2 sensitivity after 30 years of research tells us per se that the science is not settled. IPCC on a global warming of <ahref=https://www.ipcc.ch/sr15/chapter/chapter-1/>1,5°C

    "Past emissions alone are unlikely to raise global-mean temperature to 1.5°C above pre-industrial levels (medium confidence)"

    "1.5°C emission pathways are defined as those that, given current knowledge of the climate response, provide a one- in-two to two-in-three chance of warming either remaining below 1.5°C

    or returning to 1.5°C by around 2100 following an overshoot."

    GISS  actualy does show us a trend towards 1°-1,5°C ~2100 a.d. It is the natural interglacial trend. There is no evidence that our warming period is unique in its rate of warming compared to past medieval epoches

    or to the past 11 Interglacials in our ice cores

    The lowest model called the "russian model"

    What is with Planck and Bolltzmann? my guess is Lüdeckepage19
    and others are right, the saturation is already reached at PAL with 1°C

    Since the Ordovian showed how much CO2 can be absorb in the oceans, acifidication of the ocean  due to human emissions might be the bigger threat. Even though most of the CO2 was embeded in limestone, hence the CO2 "starvation".

     

    Moderator Response:

    [DB] Off-topic snipped.

  24. One Planet Only Forever at 10:49 AM on 1 November 2019
    The Scientific Guide to Global Warming Skepticism

    NPR has published a short article and 26-Minute Listen "Fake News Is Scary. Here's How To Spot Misinformation" as part of their Life Kit series of guides.

    It is a good supplement to the this Guide.

  25. Tipping Points: Could the climate collapse?

    i'd tried to respond the other day, but was having network issues...

    As to "sacrifices", general morale on the domestic front was very high during WWII mobilization (see Brinkley's "End of Reform" among many others)... suicides were at record lows, most of the population was better off in spite of rationing etc. Above all, US citizens felt they were part of an important project.

    Another note about "sacrifices" in the US.

    Much of our emissions come from the unwanted driving of 2 - 7 (e.g. Ford 150) ton blocks of steel and glass in an ellipse every day. The vast majority of the "jobs"  this is done for are materially useless.

    If we decided to re-arrange society to provide food, shelter, healthcare, education and community, we could get rid of these "jobs" everyone hates (see Graeber's "Bullshit Jobs").

    At the least, assuming you want to keep Capitalism, we could have all the nonsense jobs of the Finance, Insurance, Real Estate done from home and convert all those office buildings to housing.

    We could also re-arrange society so everyone could walk to work (if most insisted on keeping these useless sectors around).

    All this could lead to shorter work weeks and not "sacrifices" in the USA.

    Yes it would take planning away from the corporations and put it in the hands of the people, and yes you'd have to have agreement among the voters.

    Anecdotally and in polls, everyone knows this way of doing things is ridiculous. Nobody likes their commute. Many don't even like their houses. Everyone is getting sick of the increasing share spent on insurance, mortgages/rent and health insurance.

    Look at the PCE, and you'll see, people are spending more in the Financispere (that "70% consumption" number includes healthcare, education and insurance), not on consumer durables.

    In terms of political viability, 1919 everyone knew women would never get the vote. In the 1950s, everyone knew African Americans would never go to school with whites; in the 19th century everyone knew children would always work in factories...

    Better still, in 2015 everyone knew Medicare for All was fringe looney, $15 min wage was WAY out there, free college a crazy wish, student loan write offs a no way in hell...

    So we could get to 0 emiisions in 3 years if we decided to, considering WWII mobilization.

    And some people at MIT just published about a new electrochemical CO2 capture mechanism that might be scalable (not sure the time scale though, and it does uses carbon nanotubes which are pretty energy intense), so there may be hope for humans yet.

    And we could do it in a rational but most importantly, democratic fashion.

    But first a large majority of us have to agree that things could be very different once we decide to make it so.

  26. CO2 levels during the late Ordovician

    Hello, i think i stumbled across an "Undead" thread here.

    I googled for "co2 levels ordovician" and was linked here, after reading i registered and commented. After a few hours my probably flawed post was deleted. If i type "ordovician" in the SkepticalScience search bar i get 2 related links, exlcuding this thread. I guess it is obsolete, since the ppm values of Seth Young (2009) are considered wrong (5000) ppm.

     

    What kind of makes me sad is that the 2 pages of comments in this "undead" thread will get lost as contemporary witnesses (?). It is interesting to see how the debate was 9 years ago. Aint it possible to merge these threads and maybe make a notification that, at this point people had obsolete data?

    Thank you for your patience.

    Oh one more thing: The linked tool "tinypick,com" to HTML post graphs is obsolete, it now links to "Photoshop" now which is not free.

    Moderator Response:

    [PS] All threads are live. Most users follow the site with the "comments" menu item which show activity everwhere. However, your comment was deleted because it was a gish gallop and unsupported by appropriate references. Please ensure your comments conform to our comments policy.

  27. One Planet Only Forever at 09:21 AM on 31 October 2019
    Skeptical Science New Research for Week #43, 2019

    michael sweet@5,

    In addition to the improved understanding, reduced uncertainty, regarding the number of relocation refugees due to climate impacts, the next question is how soon will they need to relocate?

    The revised estimate is the number of people who will need to relocate in the 3 decades before 2050. How rapidly the relocation must begin is not certain. How many have to be relocated in each of those 3 decades?

    The follow-up is, of course, how many will have to relocate per-decade in the decades following 2050?

    And this brings up my favorite "Method of evaluation that needs to be ended - Discounting of future negative impacts". Clearly, having to relocate people in the decades after 2050 is as bad as having to relocate them today or in the decades before 2050. But the discount-rate fans defend being dismissive about future harms all the time. The further in the future, the less it matters to them.

  28. Skeptical Science New Research for Week #43, 2019

    It has been known for a long time that estimates from satellite data were greatly underestimating sea level rise damage.  Climate Central scientists showed in the USA that actual ground data showed greater damage than satellite data.  They wrote this new study 

    I imagine the biggest issue was how to correct the data in countries where ground data was not available.

    Bad news for people who live in low areas.  Hundreds of millions of refugees!  Where will they all go?

  29. One Planet Only Forever at 14:48 PM on 30 October 2019
    Skeptical Science New Research for Week #43, 2019

    doug-bostrom,

    OPOF is indeed OK.

    I also get the point of the new report. But, my personal experience with the issue is less high tech.

    This was an issue with stereoscopic aerial photogrammetry. You could fairly easily determine the elevations of what was visible. What was harder to determine was ground level under what was visible from above. Lidar was better, but not if the growth canopy was dense.

  30. Skeptical Science New Research for Week #43, 2019

    Thank you, OPOF (if that contraction is OK). 

    After boggling over the figures this morning: "how did I miss it??" It was published about 12 hours after the final sweep for #43. There's no value in being too rigid and it's quite important not least because it'll be scrutinized heavily so I'll just add it now. 

    But it seems worth a blog post of its own. The paper appears to be bad news given the limitations of foundational SRTM data and the plain, crisp way the authors are able describe those.

    Oddly enough I have some experience dealing with SRTM data on a practical level in a way that lends me confidence in the article, that of establishing microwave transmission paths in some challenging locations under tricky requirements and heavily dependent on a DEM with SRTM underpinnings. What SRTM claims is indeed heavily affected by "ground truths" in the form of vegetation and (rarely in our case) structures. It was fairly easy to see the limitations of the corrections applied to our particular SRTM-derived DEM when we checked optical paths as part of the RF path verification process. In our case the main problems manifesting from this had to do with Fresnel interference being a threat where by DEM it shouldn't. 

     

  31. One Planet Only Forever at 12:53 PM on 30 October 2019
    Skeptical Science New Research for Week #43, 2019

    I should have linked the NYTs article in mention in my earlier comment.

    Here it is: Rising Seas Will Erase More Cities by 2050, New Research Shows

  32. One Planet Only Forever at 12:49 PM on 30 October 2019
    Skeptical Science New Research for Week #43, 2019

    This Report should be included in next week's New Research list, but deserves special notice.

    New elevation data triple estimates of global vulnerability to sea-level rise and coastal flooding

    Credit to the New York Times for reporting on it so quickly.

  33. prove we are smart at 11:50 AM on 30 October 2019
    60 Years of Satellite Earth Radiation Budget Observations

    I have learnt and still learning / enjoying from this wonderful website. Thanks to all, and i often quote this site for scientific facts. Thanks for the story on our ERB, Doug.. 

  34. Water vapor is the most powerful greenhouse gas

    Agree Eclectic - shouldnt be trying to do this in a hurry.

  35. Water vapor is the most powerful greenhouse gas

    Even lower than 0.2mm

    360Gt for 1mm sealevel rise?  Call it close to 0.05mm/year.

  36. Water vapor is the most powerful greenhouse gas

    faerr - you seem to be missing the point that water vapour condenses out. No matter how much water you push up into the atmosphere by any means, the amount of water that the atmosphere will hold is dependent on the temperature. Once saturation is reached, then it just precipitates out. Burning FF does deplete O2 in atmosphere while making that water and I guess it makes an extremely tiny contribution to sealevel rise. (20Gt/y would be about 0.2mm)

  37. Philippe Chantreau at 05:11 AM on 30 October 2019
    Climate's changed before

    TVC,

    I'll add that I looked at both links in your comment above and can not understand the allusion to "government." One study from Oxford University was funded by the Gary Comer Abrupt Climate Change Fellowship, the other is from the Annals of the Brazilian Academy of Science. Unless you're from Brazil, it would suggest your interlocutor did not spend much time looking at the studies; it would be a pity because the full text is available for free on both of them.

  38. Climate's changed before

    Again many thanks to both MA Rodgers and Ecletic!

    I am also out of my depths with respect to sea-level highstands but I knew that this denier was as well and I knew enough to know that neither of his links disproved anything I stated.

    Without this site I would have to return to college and go an additional 2 years with intense focus on the science mythologies of climate change.

    Thank you so much for broadening my scientific knowledge! :)

  39. Video: Dorian’s Deadly Stall – How Climate Change is Weaponizing Hurricanes

    Last year after Hurricane Florence made her deadly stall on the coasts of the Carolinas, I sent an email to the National Hurricane Center asking them if it was time to revamp the Saffir-Simpson Scale since wind speeds are taking a backseat to rainfall and storm surges in the more recent hurricane impacts.  They agreed and said that they were indeed working on such a system, but that it may take time for acceptance since the public is so used to the Saffir-Simpson scale.  I think we would be better informed on the potential devastation for a hurricane if we knew the estimated rainfall and storm surge.

  40. One Planet Only Forever at 00:01 AM on 30 October 2019
    Skeptical Science New Research for Week #42, 2019

    Dawei@3,

    The following points may clarify my thoughts regarding "Are global tropical cyclones moving slower in a warming climate?", specific regarding it suporting a claim "...that AGW is likely *not* having an effect on cyclone speed":

    • This document attempts to be a follow-up to a previous attempt to refute an evaluation of the full global satellite data set that strives to establish if, with the limited data currently gathered, there is evidence that the rate of movement of cyclones is reducing (they are moving slower), with the related result that the total amount of rain and wind damage from a cyclone event on a location could increase. The most likely cause of such a change of behaviour would be global warming.
    • The previous critique of that report by this author resulted in modifications of the original report that did not change the conclusion of the report.
    • This new critique appears to attempt a more detailed evaluation of regional 'sub-sets of the accumulated global satellite data'. If the global total data set is only marginally large enough to identify trends in, no sub-set should be expected to be large enough to note a trend. Yet the author seems to want to claim that their identification of 'regional speeding-up of movement after the eye makes landfall (my para-phrasing)' can be identified and is the basis for refuting the global evaluation.
    • A lot of rain and wind damage can occur before the eye makes landfall. A recent major damaging storm swept up the coast of Florida without making landfall. And many others have done that. However, Dorian definitely 'sat on top of land for a long time', unlike cyclone movement after the eye finally makes landfall on a large land mass (the type of regional difference that the author seems to want to focus on - and it is possible that Dorian's behaviour above an 'island' would be excluded from the 'regional behaviour after landfall' that the author appears to want to write a story about).
  41. Climate's changed before

    TVC15 , if I may add a little to MA Rodger's Post #800 :

    your denialist friend's 2nd scientific paper quoted, is dealing with a small coastal area at the southern tip of Brazil.  The paper specifically says it has not allowed for "tectonic processes" that might modify the results.

    When you add in a quantum of uncertainty of timings locally, and at the Vostok site also . . . then really he is making no useful comparison with changes in insolation at 65N  [was your 651N a typo?] . . . nor any useful comparison with CO2 levels.  And looking at temperature changes over the course of each MIS or interglacial period, you see that each cycle shows its own unique pattern of variations against the grand sweep of glaciation/deglaciation.  From "minor" variations in insolation, ocean currents, vegetation changes, etcetera ~ and variation in sea-levels.

    Your denialist friend has not shown any evidence to disprove the role of CO2 in connection with planetary surface temperature.

    And he seems to have quite misunderstood the papers he quoted : indeed he is wasting the time of the readers.

    And tell him, regarding sea-level highstands . . . he's out of his depth!

  42. Water vapor is the most powerful greenhouse gas

    Faerr @364 ,

    it would be an interesting exercise if you made a quick back-of-envelope calculation to give a rough quantification of what you are proposing.

    Use the burning of coal/oil at an annual rate of 10 Gigatons of carbon ~ each carbon atom would liberate about 2 atoms of hydrogen (and hence 1 molecule of water vapor.   Thus (from atomic weights) . . . carbon 12 grams would produce 18 grams of water.

    So, 10 Gigatons of carbon producing 15 Gigatons of water vapor annually (but probably a shade more, allowing for coal impurities and shorter-chain oily compounds).   Let's round up to 20 Gigatons of water injected as vapor into the atmosphere, annually.  You might have to subtract a bit from that (but how much?) to allow for coal/oil burnt in wintry & far northern regions, where you might expect much vapor to condense and "rain out" rather quickly.  And the purer & dryer the coal, the less the water liberated.

    But for simplicity, let's stay with 20 Gigatons water = 20 cubic kilometers of liquid water, annually.

    I can't vouch for Wikipedia's accuracy, but Wiki says the world's annual precipitation is 505,000 cubic kilometers.  In other words, so large that it seems completely justifiable for the scientists to choose to ignore the 20 cubic kilometers.  ( I am without coffee, so please check with your own pen & envelope.)

  43. Climate's changed before

    TVC15 @799,

    It is a rather incoherent rant from your denialist. When you raise the point that only two of the last 8 interglacials were higher than today, he responds "No, it's every single one of them." Yet nothing he presents (his "science") is saying that all past interglacials had sea level above today. Indeed none are saying that global sea level was any different to your assertion (2 of 8 higher).

    He presents two references.
    Henderson et al (2006) is discussing the timing of the interglacial high stand in the Bahamas during MIS7 & MIS9 (note MIS9 is also one of the 2 past interglacials that were higher than today). They were certainly not considering the height of the peak sea level globally. Even if Henderson et al were discussing the height of the highstand, the isostatic movement of land means a local measure of relative sea level is not a reliable marker of global sea level. Nowhere do Henderson et al mention isostatic land movement. The height of the highstand is not their thesis, the timing is. (Note in the following reference Lopes et al, fig 6 shows the MIS1 holocene highstand 4 metres above present sea level. This would be down to local isostatic movement.)

    The denialist's second serving of "science" is Lopes et al (2014) is again primerally concerned with dating and having concluded that it is an MIS7 highstand they have identified, do not proclaim that MIS7 sea level has been underestimated (as the denialist concludes). Instead they look to find reason for their highstand being higher than they would have expected, their suggestion being that plate tectonics may be at work.

    The denialist then sets out non-controversial CO2 levels from the Eemian. Quite how this links to his final grand "science says" assertion can only be speculated. Is he saying that if CO2 was below 300ppm in the Eemian with its higher sea level, then (sarcastically perhaps) with CO2 at 400ppm today sea level must rise?  Strangely, this is the case. The warming resulting from increased CO2 will add perhaps 2.3m/degree C to global sea level, according to IPCC AR5.

  44. Water vapor is the most powerful greenhouse gas

    My first post, may it be interesting.  I read these two posts concerning water vapor and GHG. My comment is that for the current level of 409 ppm, there must have been a much higher corresponding amount of water vapor emitted by burning fossil fuels (putatively how the CO2 is formed, eh?).  Now there is a small exception of coal.  However, since a given hydrocarbon has more Hydrogens than Carbon, the worst ratio being Methane 4:1 H:C and thus 2 molecules H2O to 1 molecule CO2 perhaps this will make up for coal then.  So given the increase in water vapor, where is this considered?  To me it seems that some scientists have oversimplified or missed or ignored it.  It is far too easy to follow CO2, but not so easy to follow increased atmospheric water vapor until it enters the water cycle of ecosystem. 

  45. Climate's changed before

    MA Rodger @788

    OK so I shared the link showing that only two of the last 8 eight had sea level rise higher than today and this is what he came back with.

    No, it's every single one of them.

    Here's more science showing sea levels in MIS-7 and MIS 9:

    The presence of a sea-level highstand at E180 ka represents a challenge to the idea that Pleistocene climate is driven by summer insolation at 651N. Sea-level is increasing (and therefore ice is melting) when 651N summer insolation is at one of its lowest points of the last 400 ka.

    [emphasis his the denier]

    Recognition of non-Milankovitch sea-level highstands at 185 and 343 thousand years ago from U–Th dating of Bahamas sediment

    https://www.whoi.edu/cms/files/Hende...2006_21693.pdf

    Here's another on MIS-7...from your own government....omigod...how can you debunk your own government?

    Thermoluminescence (TL) and electron spin resonance (ESR) ages from sediments and fossil shells point to an age of ?220 ka for the end of this marine transgression, thus correlating it to MIS 7 (substage 7e). Altimetric data point to a maximum amplitude of about 10 meters above present-day mean sea-level, but tectonic processes may be involved.

    https://www.ncbi.nlm.nih.gov/pubmed/25590701

    Sucks to be you.....you can't scream, "Oil company funded research!"

    The last interglacial (LIG; also known as the Eemian or MIS5e) lasted from 129 to 116 thousand years before present (ka).

    If we look at EPICA Ice Core Data for CO2 levels in ppm, we find:

    YBP ..... ppm CO2

    116,501.... 262.5
    117,750.... 267.6
    118,649.... 273.7
    119,672.....271.9
    120,382.... 265.2
    121,017.... 277.6
    122,344.... 272.1
    123,070.... 276.4
    124,213.... 268.7
    124,257.....266.6
    124,789.... 266.3
    125,081.... 279.7
    125,262.... 273.0
    125,434.....277.1
    126,347.....273.7
    126,598.....267.1
    126,886.... 262.5
    127,132.....262.6
    127,622.... 275.3
    127,907.... 275.6
    128,344.... 274.0
    128,372.....287.1
    128,609.....286.8
    128,866.....282.6
    129,146.....264.1
    129,340.....263.4
    129,652.... 257.9
    129,736.....259.0

    For a brief period, CO2 levels were in the 280s ppm CO2, but for the most part below that and the average is only 271.7 ppm CO2.

    That, is Science, and Science says sea levels are going to rise and you can't stop it.

    I've never stated that sea levels are not going to rise so him tossing that in at the end is a non sequitur.

    I don't think that either link he posted is refering to sea-levels being higher than the two interglacials you mentioned in 784. (only two previous interglacials that saw such sea levels - the Eemian (MIS-5e) and 400,000y bp the MIS-11).


  46. 60 Years of Satellite Earth Radiation Budget Observations

    Heh, this article was written in extreme haste when I realized we were about to ignore an important birthday. And the author is a mile wide and an inch deep, with shoals. :-0

    Yes, moving the decimal to the correct position and using 2013 figures, our own power delivery is about 18TW. 

    Yup, wrong on total imbalance expressed as instantaneous power. Digging on this, I find I made exactly the same mistake as Greg Easterbrook, so at least I'm in superior company. Details of how to go wrong here: How much extra energy are we adding to the earth system?

  47. 60 Years of Satellite Earth Radiation Budget Observations

    It is definitely worth memorializing the beginning of observational (satellite) measurements of Earth’s Radiation Budget (ERB). A couple of caveats about the information in the explanatory background on the ERB (that have no effect on the overall message of the article) seem in order. The first has to do with the present energy imbalance. If we take this as 0.8 watts per square meter, then the total over the Earth’s surface (about 5 x 10^14 square meters) is about 400 terawatts, not “well over a thousand terawatts”. Second, the International Energy Agency has the total energy used by all human activities now nudging 20 terawatts, not 1.2 terawatts from “human manipulation of energy from all sources”. The comparison of 5% from human activity is negligible, but not as trivial as the article implies. It seems important, in communicating about climate science and climate change, to make sure these kinds of details are correct, so readers can be confident that the rest of the material is also trustworthy.

  48. A small electric plane demonstrates promise, obstacles of climate-friendly air travel

    Further to Rob's remarks, as I read it the objective of hybrid aircraft is to employ batteries and electric assist to reduce fuel guzzling during take-off and a portion of ascent. 

    JATO: particulate emissions from aviation boost rockets as an elliptical geoengineering scheme? Hmm. Maybe we'd best remain silent on this. :-)

    Leisurely aviation: go to ntrs.nasa.gov, plug in "dirigible" and "airship" as search terms, sort results in ascending order and one sees a picture of a world that did not happen, with airships occupying the top slot in commercial aviation. However it wasn't so much problems with lifting gas that truncated this path as issues with control of the vehicles in inclement weather, particularly during docking and while at dock. 

  49. Climate's changed before

    Eclectic @796

    MA Rodger @ 797

    Thank you both so much! I learn so much everytime I come here and post the weird things that denialists state.

    Thank you both so much!

  50. One Planet Only Forever at 01:52 AM on 29 October 2019
    Skeptical Science New Research for Week #42, 2019

    Dawei@3,

    Doug has provided a good reponse regarding the section the Report is listed under.

    I will provide the following in an effort to respond to the other parts of your comment.

    The abstract ends with the following: "The relationship between the slowdown of tropical cyclones and anthropogenic warming is therefore not apparent and the relevant potential increase in local rainfall totals in the future warming climate is suspicious."

    That appears to be inconsistent with claiming "...that AGW is likely *not* having an effect on cyclone speed".

    My comment was pointing out that, in addition to reading the complete abstarct, reading just a little further raises even more doubts about the claim "...that AGW is likely *not* having an effect on cyclone speed".

    Along the lines of Doug's point regarding the category for the Report, claiming to doubt a conclusion of another report that has already been corrected without the corrections affecting the conclusions seems to indicate that serious skepticism should be applied regarding the claims this report appears to try to make. The author is not refuting the revised conclusion of the other report. They appear to be trying to tell a different story based on their personal interpretations of selective information.

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