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Comments 28101 to 28150:

28101. KR at 23:39 PM on 9 July 2015
       2015 SkS Weekly Digest #27
       

       MIchael Fitzgerald - Keep in mind that satellites are not looking at a single emitting layer at a single temperature, but rather a range of wave-length dependent radiating altitudes where given the GHG spectra the majority of emissions can reach space. I've commented previously on this topic here. 

       Secondly, it's entirely clear to me whether you're accounting for the lapse rate between the effective emission altitude and the surface - the Stephan-Boltzmann dependent emissions from TOA are in essence amplified by the lapse rate to actual surface changes. 

28102. Kevin C at 23:18 PM on 9 July 2015
       Climate denial linked to conspiratorial thinking in new study
       

       By word count the original study comprises less than half (about 45%) of the new study.

28103. Tom Curtis at 22:50 PM on 9 July 2015
       2015 SkS Weekly Digest #27
       

       MA Rodger @16, thankyou.

28104. Tom Curtis at 22:42 PM on 9 July 2015
       Climate denial linked to conspiratorial thinking in new study
       

       ryland @12, the specific claim in the blog post to which you link is:

       "As a result of its investigation, which was carried out in respect of academic, ethical and legal factors, Frontiers came to the conclusion that it could not continue to carry the paper, which does not sufficiently protect the rights of the studied subjects. Specifically, the article categorizes the behaviour of identifiable individuals within the context of psychopathological characteristics."

       It is not mentioned whether or not the rights which are "not sufficiently protected" were ethical rights, or legal rights, or (quite frankly) fantasy rights.  Given this, and given the statement in the official communication, you are not entitled to interpret those rights as ethical rights.  

       Nor is it stated that the rights were violated.  Taking insufficient steps to protect a right is not the same thing as violating a right.  You can take insufficient steps to prevent pregnancy, and still have no pregnancy eventuate; and likewise you can take insufficient steps to protect a right without that right in fact being infringed.  Of the nature of rights, it is only infringement of rights that can constitute an ethical violation; whereas insufficient measures to protect rights can leave one open to legal liability (on grounds of negligence) even when no right is in fact infringed.

       Further, the supposed right to not have your behaviour categorized if you are identifiable, and if it is in the context of discussion of "psychopathological characteristics" is very vague.  There is an ethical duty on psychologists to not diagnose people without consultation; but categorizing behaviour in the context of psychopathological characteristics is not diagnozing them.  Saying somebody has "conspiracy ideation" is not diagnozing them as a conspiracy theorist, which is not a psychopathological diagnosys in any event.  Any theory that suggests doing so is an ethical breach shows absurd levels of overreach.  It is also (given the normal fare on denier blogs) a massive hypocrissy to claim it is an ethical violation.

       However, categorizing people's behaviour can lead to people mistakingly assuming a diagnosis has been made where no diagnosis has been made.  That is, it can lead to potential issues with regard to libel.

       So, there is nothing in the blog post to which you refer which contradicts the official statement, and subsidiary evidence in that blog post strongly suggests it was in fact legal issues that created the problem - said legal issues being vapourware as shown by the lack of legal response to the continuing publication of the paper on the UWA website.

       Finally, while the recent paper is related to the retracted paper, it apparently also includes new research.  Ergo it is not just a reboot of that paper.  However, I cannot comment on the exact extent of similarity, having not read the recent paper.

28105. jgnfld at 22:14 PM on 9 July 2015
       Climate denial linked to conspiratorial thinking in new study
       

       As this is a republication of the original results with additional reconfirmation and further work to extend the findings but now in a journal perhaps more directly on topic the "unethical" argument goes by the board. The remaining argument is the litigation fear of the original publisher.

       
       Those engaging in conspiratorial thinking on public forums may now sue. It is their perogative. I am unsure as to what country's legal system would apply and doubt such a suit would get much shrift anywhere but they are now welcom to try. Of course they were welcome to try suing UWA over the past year which hosted the paper and failed to do so.

28106. Kevin C at 22:13 PM on 9 July 2015
       Climate denial linked to conspiratorial thinking in new study
       

       I am slightly troubled by your use of language: the second response from 'Frontiers' didn't 'show' anything. Both the first and second responses made claims, and those claims contradicted one another. For context, the second response from Frontiers came after a significant amount of criticism had been directed at Frontiers over the incident.

       There are a number of possible interpretations. The first response from Frontiers might have been an attempt to be diplomatic. Or the second might have been an attempt to save face. The correspondance between Frontiers and the university might provide more insight on the question.

       There are multiple issues being conflated here:

       1. Was the research ethical according to the norms of the field?
       2. Was the research ethical according to the norms of the university?
       3. Was the research ethical according to the norms of the journal?
       4. Did 'Frontiers' consider the research to be ethically problematic, or were they simply making an expedient argument to justify their actions? (This contains the further simplification that an organization can hold an opinion.)

       There appears to be a significant amount of literature on the use of internet communications in research - here are the first two that I found. A survey of recent opinion on the question would be interesting.

28107. ryland at 21:22 PM on 9 July 2015
       Climate denial linked to conspiratorial thinking in new study
       

       As always Tom Curtis thank you for your comment.  Although you do not specifically say so, I gather from your  comment the paper is not new.  You are quite correct that the initial statement from the Journal made on March 27 2013 did state there were no issues with academic or ethical aspects  of the study. This however was contradicted in a later statement from the  Journal on April 4 2013 which does indeed show retraction was on ethical grounds.  I append that statement below (my emphasis}  

       "As a result of its investigation, which was carried out in respect of academic, ethical and legal factors, Frontiers came to the conclusion that it could not continue to carry the paper, which does not sufficiently protect the rights of the studied subjects. Specifically, the article categorizes the behaviour of identifiable individuals within the context of psychopathological characteristics. Frontiers informed the authors of the conclusions of our investigation and worked with the authors in good faith, providing them with the opportunity of submitting a new paper for peer review that would address the issues identified and that could be published simultaneously with the retraction notice."

       The authors agreed and subsequently proposed a new paper that was substantially similar to the original paper and, crucially, did not deal adequately with the issues raised by Frontiers.

       One of Frontiers’ founding principles is that of authors’ rights. We take this opportunity to reassure our editors, authors and supporters that Frontiers will continue to publish – and stand by – valid research. But we also must uphold the rights and privacy of the subjects included in a study or paper.  The reference is here,  

       In fairness I must note however that the retraction of the paper was controversial and Ugo Bardi the chief specialty editor  of Frontiers in Energy Research, Energy Systems and Policy resigned in protest against the retraction.  In so doing he stated:

       "The climate of intimidation which is developing nowadays risks to do great damage to climate science and to science in general. I believe that the situation risks to deteriorate further if we all don’t take a strong stance on this issue". `see here

       All that said, to repeat what I said above, I gather this is not a new paper but a revamp of the paper retracted by Frontiers. 

28108. ranyl at 21:20 PM on 9 July 2015
       Carbon cycle feedbacks and the worst-case greenhouse gas pathway
       

       tmbtx,

       Presuming there is a carbon debt, then any additional carbon emitted to atmosphere adds to that debt, (i.e. any additional carbon emissions), therefore the carbon needed to manufacture renewables or anything else for that matter is an addition to the debt.

       All renewables are carbon emissions dependent to manufacture, as they are made of materials like concrete, aluminium, steel, metallic grade silicon, rare earth metals, etc, all of which require large scale mining, large amounts of energy and create significant amounts of general and toxic waste.

       There is little doubt that over time producing energy from a wind turbine in comparison to coal, gas or liquid fossil fuels, costs a lot less carbon emissions, causes much less toxic waste, mining disturbance and has a significantly lower adverse impact on general biodiversity. However that doesn't mean wind turbines are clean for they do have associated with carbon emissions and do have adverse affects on biodiversity, they are just far far less dirty than coal.

       Clearly the renewables that have been manufactured should be used until they cease to function, although maybe they should positioned optimally, (e.g. putting the solar panels already manufactured on south facing roofs rather than in fertile fields?)

       However on the premise of stopping all fossil fuels use ASAP, (meaning there is no fossil fuel burning displacement carbon emissions payback for renewables), then they do have a definitive carbon cost and biodiversity impact. Add in the batteries needed and the impacts of manufacturing and disposing of these batteries and the general costs rise, and the end of life of renewables also has to be considered; what is the end of life of a large scale hydro dam?

       Given the gravity of the situation faced and considering the scale carbon debt (Is 350ppm safe? maybe 300ppm (300ppm =1C rise, 6-9m sea level rise), for me the question is how much more carbon emissions and biodiversity impacts can be gambled?

       Further given 1.5C isn't seemingly that safe (considering the weather already?), and 350ppm by 2100 might keep the temperature rise to between 1.5C and 2C, (although 3C-5C more in the longer term and with eventual sea levels rises of ~15-25m, if the early Pliocene is anything to go by), again is 350ppm safe?

       What would getting the atmospheric CO2 levels down to 350ppm take?

       95% power down?

       Not using the power means no carbon emissions and no biodiversity impacts. Further due to the reduced power generation biodiversity should increase and therefore carbon should be sequestered. Therefore reducing down, in terms of energy use saves the most carbon emissions, increases biodiversity and removes carbon dioxide from the atmosphere to some degree as biodiversity enriches.

       Cars?

       Think of rubber plantations, road impacts, road deaths (biodiversity and people), manufacturing impacts, disposal impacts, what do electric cars become at the end of their life, even if recycled a few times?

       And when considering all this also note the degree of adaption that is going to be required, planning for 1:1000 extreme weather isn't easy, and if go up 2C, then 1:1000 event will be mild merely by the shift in mean temperature by 5 standard deviations and this will affect infra structure and crops (e.g. wind, flood, hail, drought).

       Is it possible to go back to sailing rather than flying?

       Would imagine with human ingenuity to ships would be impressive, however who wants to go back to skilled craftsmen building wooden ships as wood in an appropriate amount can be truly sustainable?

       What would it require to actual stop using fossil fuels?

       And what is sustainable?

       Renewables utilise renewable energy sources (e.g. the sun) however they are machines and aren't renewable in themselves (as in they don't renew themselves), as they need to be manufactured and that costs carbon emissions and has biodiversity impacts. Further all renewables also impact biodiversity to some degree in use. Not as much as fossil fuels by any means, however still impacts when biodiversity is falling rapidly, therefore minimising these seems reasonable. And not needing as many renewables by using much less power reduces these impacts the most. That is the less renewables acutely required for functionality the easier it will be to achieve ecosystem regeneration.

       Biomass can potentially be grown sustainably in the long term and without displacing food crops, displacing soil carbon or negatively impacting biodiversity (e.g pesticides, fertilisers), the question is how much? and what is the best done with its limited supply?

       Ambulances or X-Boxes?

       Therefore tmbtx,

       Is there hope?

       I agree overall at the present getting energy sourced from renewables is much better than getting it from fossil fuels, therefore positive to a degree.

       However, again not as positive, as not using the energy.

       And if only it was just about energy production as the debate is so always shifted, when biodiversity losses are just as, if not more worrying, and over fishing in an electric boat is just as impacting as over fishing in a petrol one and cars do kill a lot of birds each year as any wind turbine manufacturer will confirm.

       Personal cars?

       And then there will climate displacement of large numbers of peoples, is current situation that well suited for mass migrations?

       Also if 350ppm is seen as safe, and that is a large carbon debt, the higher we go above that the larger the debt becomes.

       And to get 350ppm given the melting permafrost, forest fires, tree die offs (which will continue to increase in scale as there is warming in the system), basically means becoming massively carbon sequestering as soon as possible. And further the carbon that was taken up into the forest and sea sinks will be re-released as the atmospheric CO2 falls, which means to get 350ppm by 2100 would require removing ~twice amount of carbon dioxide that has been accumulated in the atmosphere plus removing the additions from the permafrost etc.

       At present 1:5 or more (worldwide) don't even feel climate change is happening although I'm not aware of the current perceptions of the biodiversity crisis.

       What scale of change would be needed to achieve that massive amount of true carbon sequestration by 2100, whilst also adapting to the changes to come and repairing the earth's ecosystem?

       Is there hope?

       What are the carbon costs of war and destruction?

       Syria?

       Is there hope?

       For me I suppose theoretically yes, although only if there is a paradigm shift in the perception of the problem, a massive reduction in power use, the cessation of fossil fuels use within 5-10years, and stopping of using non sustainable materials and the transformation of human interactions with nature and each other, in order to facilitate a sustainable society and ecosystem regeneration.

       Is there hope though?

       Not sure, however whilst the focus remains on BAU replacement with renewables then for me it is definitely no.

       Is there hope?

       I wish I could say yes, but as mentioned to most the mobile phone is essential.

28109. bozzza at 21:00 PM on 9 July 2015
       2015 SkS Weekly Digest #27
       

       Surely the question,"...what is the sensitivity as a function of temperature?", can't be answered!

       Moderator Response:

       [PS] Well yes, but a very carefully worded restatement could be - ie something like how much extra temperature change would there be for a purely forced temperature change of 1 degree. It still comes down to magnitude of feedbacks - and also timeframe of interest since have both fast and slow feedbacks.

28110. MA Rodger at 20:52 PM on 9 July 2015
       2015 SkS Weekly Digest #27
       

       Tom Curtis @9,

       The 65 is an approximation of σ-¼ = 64.8.

       j*=σT⁴

       T = σ^-¼ x j*^¼= 64.8 j*^¼

       dj*/dT = ¼ x 64.8 j*^-¾

       This gives the slope of the Stephan-Boltzmann equation which at j* = 238.5 Wm^-2 yields a slope of 0.2669444ºC/Wm^-2. The approach employed @12 by Michael Fitzgerald gives a slope of 0.2669446 ºC/Wm^-2. As the concept of climate sensitivity compares ΔT resulting from a doubling of CO2 where ΔF = 3.7 Wm^-2, zero-feedback sensitivity = 0.267 x 3.7 = 0.99ºC which happily is the value quoted in climatology and Wikipedia.

       "Without any feedbacks, a doubling of CO2 (which amounts to a forcing of 3.7 W/m2) would result in 1°C global warming, which is easy to calculate and is undisputed." (My emphasis.)

28111. Tom Curtis at 20:24 PM on 9 July 2015
       Climate denial linked to conspiratorial thinking in new study
       

       ryland @10, the retraction of Recursive Fury stated:

       "In the light of a small number of complaints received following publication of the original research article cited above, Frontiers carried out a detailed investigation of the academic, ethical, and legal aspects of the work. This investigation did not identify any issues with the academic and ethical aspects of the study. It did, however, determine that the legal context is insufficiently clear and therefore Frontiers wishes to retract the published article. The authors understand this decision, while they stand by their article and regret the limitations on academic freedom which can be caused by legal factors."

       (My emphasis)

       Transparently, your claim that Recursive Fury was withdrawn "for ethical reasons" completely misrepresents the case.  Rather, a small group of people were so determined to prevent the publication of Recursive Fury that they were threatening legal action, and the publisher was overly cautious.  That they were overly cautious was shown by the fact that the paper remained available for over a year at the UWA with no legal action being taken.

28112. ryland at 19:27 PM on 9 July 2015
       Climate denial linked to conspiratorial thinking in new study
       

       Is this a new paper as your headline states or is it a revamp of the paper Recursive Fury that was withdrawn for ethical reasons from The Journal of Social and Political Psychology?  

28113. uncletimrob at 17:47 PM on 9 July 2015
       Climate denial linked to conspiratorial thinking in new study
       

       This kind of study is very interesting as it reflects what we (I) see in my profession as a teacher - if there is no explanation that I can understand or accept then there MUST be something else happening eg "they all hate him/her" , "he/she is being picked on" , "this school really has it in for (name your group) people".  I suspect it is a way of aligning or justifying  some core beliefs/ideas/biases with what is actually the truth. Alternatively it is a way out as it allows the user to justify an exit because the alternative is just to uncomfortable to consider.

28114. Rob Honeycutt at 16:44 PM on 9 July 2015
       We're heading into an ice age
       

       Echo_Alpha...  Then if it's a fact you should be able to show us the research that supports that position.

28115. MIchael Fitzgerald at 15:51 PM on 9 July 2015
       2015 SkS Weekly Digest #27
       

       There is definitely some surface of some radius where radiative fluxes are in balance.  The specific temperature of rarified upper atmosphere gases shouldn't be very important as their specific emissivity is so close to zero they contribute little to the flux of photons leaving the planet.  We should be able to define some radius where the net flux of photons is on average zero, beyond which power emissions drop off as 1/r^2.  From space, this radiation is directly measured by weather satellites whose LWIR senors see surface emissions and see cloud emissions but do not see LWIR emissions from anything above the troposphere except perhaps buried in the noise.

       You are saying that this boundary is about 5 km above the surface.  This seems to low to me since clouds can extend to the top of the troposphere and the coldest cloud tops are about 260K.  5 km above the top of the troposphere seems more plausible.  Anyway, getting late here, will pick this up again tomorrow. 

       Thanks for your time,

       Michael

28116. Tom Curtis at 15:07 PM on 9 July 2015
       We're heading into an ice age
       

       Echo_Alpha @363, evidence please.  Or are you only interested in sloganeering?

28117. Tom Curtis at 15:05 PM on 9 July 2015
       2015 SkS Weekly Digest #27
       

       Michael Fitzgerald @12 and 13, what you call TOT (Top of Troposphere) is by convention called Top of Atmosphere (TOA) by climate scientists.  The IPCC Annexe III for WG1 says:

       "Radiative forcing is the change in the net, downward minus upward, radiative flux (expressed in W m–2) at the tropopause or top of atmosphere due to a change in an external driver of climate change, such as, for example, a change in the concentration of carbon dioxide
       or the output of the Sun."

       As you can see, " top of atmosphere" is given as an alternative term for the tropopause (by definition the top of the troposhere).  The reason for this convention is probably partly historical and partly convenience.  As to convenience, the difference between radiative fluxes at the top of the troposphere and at the (very ill defined) highest altitude with gaseous content is small, as you note yourself, so that the convention make little difference in the approximate estimates in which it is used.  Historically, early climate models did not include a stratosphere, so that the Top of Model (the other term you will see) was also the tropopause), which I presume helped give rise to the convention.

       If you want to discuss the literal top of the atmosphere, we face a problem that it is undefined.  The Karman line is, by convention, the demarcation between the "atmosphere" and "outerspace", but it demarcates the lowest levels of the thermosphere as being in the atmosphere, while the bulk of the thermosphere is treated as being in outerspace.  Ergo it is an entirely arbitrary demarcation with no physical basis.  Worse, the particles in the thermosphere still act as a gas meaning that however tenuous, they are an atmosphere.  Further, the thermosphere is radiatively significant (although almost inconsequential as regards surface temperatures).

       Moving on, the temperature at the top of the gaseous envelope of the Earth is not 255 K.  Depending on whether you define it as the Stratopause, Mesopause, Karman line, or Thermopause it is approximately 275 K, 180K, 220 K, or much greater than 270 K.

       

       Where the temperature is 255 K (ignoring temporal and geographic variation) is the average altitude of radiation to space, also known as the skin layer.  This can be treated withto a reasonable approximation as the altitude within the troposphere whose temperature matches that of the skin layer, or about  5 km above the surface.

       Finally, the advantage of using the tropopause to define radiative forcing is that the temperature at the tropopause is fixed relative to the surface by the lapse rate induced by convection.  That means that temperature changes in the tropopause are more or less constant with altitude, ie, a 3 C increase in temperature at the tropopause will result in a 3 C increase at the surface, and vise versa.  This again is only true averaged across the diurnal and seasonal cycle, and ignores the effects of the increase of altitude of the tropopause with increased global warming, and the lapse rate feedback (ie, the cause of the tropospheric hotspot).  This relationship of equivalent temperature changes allows you to reason out the effects of radiative forcing without needing always to use a full GCM (which is the only way to avoid such rule of thumb reasoning).

28118. MIchael Fitzgerald at 13:59 PM on 9 July 2015
       2015 SkS Weekly Digest #27
       

       Moderator,

       The page you pointed me to was all the uncertainties.  The other page 82 is a different document.  Anyway, in the document you refered me to radiative forcing was defined as,

       Radiative forcing (RF) is a measure of the net change in the energy balance of the Earth system in response to some external
       perturbation. It is expressed in watts per square
       metre (W m–2); see Box TS.2

       Box TS.2 on page 53 defines it more precisely as a net difference at the top of the troposphere after the stratosphere has arrived at equilibrium but keeping all other state, including surface temperature, constant.

       Thanks for the reference.

28119. Echo_Alpha at 13:15 PM on 9 July 2015
       We're heading into an ice age
       

       The fact is that through out recorded history a significant increase in Volcanic activity along with a weak solar maximum has always been a precursor to an Ice Age. Anything that has skeptical in its name is bullshit. They are skeptical about the truth and the evidence that goes with it.

       Moderator Response:

       [PS] Welcome to Skeptical Science. Please take your time to familiarize yourself with the Comments Policy. Conformance in not optional. Please in particular note the prohibition on sloganeering. If you wish to challenge the science, then do so with evidence, preferably from peer-reviewed sources. Thank you.

28120. MIchael Fitzgerald at 12:25 PM on 9 July 2015
       2015 SkS Weekly Digest #27
       

       It is at 238 W/m^2 which corresponds to the 255K temperature of the planet from space.  238 W/m^2 -> 254.53 and 239 W/m^2 -> 254.8K for a difference of 0.28K per W/m^2.  If I do the other calculation to 2 decimal places (instead of 1) I also get 0.28K per W/m^2.  One W/m^2 of forcing from the Sun after reflection is the same at all altitudes from TOT to TOA so why is there any distinction (You said forcing is defined at TOA, but I thinkj you meant TOT)?  The input power is still 239 W/m^2 (up from 238 W/m^2) and the sensitiivty is defined to be relative to this difference.  I don't see how the temperture at TOT is relevant.  The temperature at TOA is 255K.

       Also, isn't the current surface temperature consequential to 238 W/m^2 of input and that 150 W/m^2 of additional warming power already the LTE (i.e. after all feedback has been accounted for) result?  What additional feedback can make that much difference?

       Moderator Response:

       [PS] A quick look at the IPCC Technical Summary, especially TFE.6, pg 82 might help getting you on the same page with respect to definitions etc.

28121. Tom Curtis at 12:06 PM on 9 July 2015
       Explainer: the models that help us predict climate change
       

       Hick'ry, try here for a starter.  The page explicitly explains CO2 lasers, so does not cover some of the important factors for atmospheric absorption, but covers the basics reasonably well.  You will notice that of the three types of modes that allow CO2 to absorb or emit IR radiation, the most important in the atmosphere is the bending mode, that absorbs or emits radiation at 667 cm^-1.

28122. Tom Curtis at 11:52 AM on 9 July 2015
       2015 SkS Weekly Digest #27
       

       Michael Fitzgerald @10, the slope of the Stefan-Boltzmann function at 250 W/m^2 is 0.258 Degrees K per Watt/m^2.  At 400 it is 0.181 Degrees K per Watt/m^2.  Neither is λ.  That is because λ includes not only the planck response (ie, the slope of the Stefan-Boltzmann function) but also the further effect of any feedbacks.  These increase the temperature response by 1.5 to 4.5 times the base response, ie, increase λ to 0.39 to 1.16 K/W/m^2.  

       I used the value of the Planck responce at 250 W/m^2 for that calculation because forcings are calculated for the TOA (ie, near to the effective altitude of radiation to space where the temperature calculation does not include the greenhouse effect), and hence λ is defined for that altitude as well.  We could calculate a climate sensitivity parameter for surface forcings but the values would differ from the more conventional calculation for the TOA. 

28123. MIchael Fitzgerald at 11:07 AM on 9 July 2015
       2015 SkS Weekly Digest #27
       

       OK. But isn't ΔT/ΔF (λ) just the slope of the Stefan-Boltzmann relation at 255K?  In your calculation, you added 150 W/m^2 of extra warming power to the 238 W/m^2 of solar power (255K).  That being said, increasing 238 W/m^2 to 239 W/m^2 should only result in another 0.63 W/m^2 to the 150 W/m^2 of warming resulting in a surface temperature of 287.9 K which is 0.3C warmer, or 0.3C per W/m^2 and not 0.75C per W/m^2.  Where does the extra 0.45C come from?

28124. Tom Curtis at 11:06 AM on 9 July 2015
       2015 SkS Weekly Digest #27
       

       MA Rodger @7, you appear to have taken the derivative of formula (1) @8, which gives (if I have done this correctly):

       (3) dT/dF = 1/σ*0.25*(j*/σ)^-0.75

       However, you express the relationship between σ and j* as a product rather than a ratio, and I am not sure how you derive the value 65 in your concluding sum which eliminates σ from the calculation.  Could you clarrify.

28125. Hick'ry at 10:21 AM on 9 July 2015
       Explainer: the models that help us predict climate change
       

       Can you point at a presentation on the CO2 infrared absorption process? Many thanks.

28126. L. Hamilton at 09:10 AM on 9 July 2015
       Climate denial linked to conspiratorial thinking in new study
       

       But getting back to "Recurrent fury" ... it occurs to me that the "do you trust scientists for information about X?" questions we've been asking on surveys basically tap into the obverse. Who trusts scientists? People *not* inclined toward conspiracy thinking.

       

       Moderator Response:

       Duplicate image removed.

28127. Tom Curtis at 08:57 AM on 9 July 2015
       Climate denial linked to conspiratorial thinking in new study
       

       Michael Fitzgerald, I have responded to your questions here.

28128. Tom Curtis at 08:56 AM on 9 July 2015
       2015 SkS Weekly Digest #27
       

       Michael Fitzgerald from elsewhere asks "...what is the sensitivity as a function of temperature?"

       The simplest response is that the sensivitity function is given by the Stephan-Boltzmann law, j* =  σ * T⁴, where j* is the power in Watts per meter squared, σ is the Stefan Boltzmann constant, and T is the temperature, in this case the Global Mean Surface Temperature (GMST).

       Transforming the equation to a formula for temperature, we have:

       1) GMST = (j*/σ)^0.25

       j* in turn is the sum of the effect of all forcings and all feedbacks.  That is, it is the globally averaged insolation, times (1 - albedo) plus the total greenhouse effect.  Putting those numbers in we have

       GMST = ((0.25 * 1360 * (1 - 0.3) + 150)/σ)^0.25 = 287.6 K, or 14.46 C

       Very clearly this is an approximation as I have ignored emissivity, which raises the temperature in degrees K by a degree or so (as the Earth is not a perfect black body at IR temperatures), and the uneven distribution of surface temperatures (which would lower it by approximately the same amount), but it is a pretty good estimate, as can be seen by comparison with the estimates from observations (14 C from HadCRUT4, 13.4 from GISSTEMP) and from models (CMIP5 mean of 13.7 C) which take far more detail into account (right section of graphs).

       

       Using all known energy sources for the Earth's surface and the current total greenhouse effect (rather than that from the 1980's as used in the calculation above), the estimate absolute temperature using this formula comes out at 289.65 K, but again given the approximations involved that is quite good.

       From your discussion with MA Rodger, it appears that you may be confusing the result of this equation with the Climate Sensitivity Factor, λ, which is defined such that the temperature response to a given forcing (ie, not including feedbacks) that perturbs the Earth's temperature from a prior quasi-equilibrium is:

       2) ΔT = λ * ΔF

       where ΔT is the change in temperature, λ is the climate sensitivity factor (having units of degrees C per W/m^2) ΔF is the change in forcing.  This works as a linear approximation only for small perturbations relative to the total incoming energy plus total greenhouse effect.  Further, it only works for conditions approximately like those currently existing.  Clearly at very low temperatures λ would be much different from current values both because of the larger planck response to temperature (ie, the response based on the Stefan-Boltzmann law), and because many feedbacks that currently exist would not exist, or be very much weaker.  For example, much below the freezing point of water there is no water vapour feedback and essentially no albedo feedback.  More than a hundred degrees below the freezing point of water and there is essentially no greenhouse effect (because all of the CO2 would have precipitated out of the atmosphere), and so on.  It follows that it is a mistake to try and apply formula (2) except in current conditions.  However, in current conditions, λ is for all intents and purposes  the "sensitivity as a function of temperature", and is approximately 0.75 which corresponds to a climate sensitivity of 2.8 C per doubling of CO2.

28129. MA Rodger at 07:00 AM on 9 July 2015
       2015 SkS Weekly Digest #27
       

       Michael FitzGerald @here.

       You say @that3 "Your equation seems to assume that dT/dF is linear" but my equation is dT/dF = 0.25 x 65 x F^-0.75. How can that be linear?

28130. MA Rodger at 07:00 AM on 9 July 2015
       Climate denial linked to conspiratorial thinking in new study
       

       Michael Fitzgerald @5.

       The Weekly Digest is sort-of Open Topic thread. I'm surprised this is needing more than a single Q&A, but...

28131. MIchael Fitzgerald at 06:38 AM on 9 July 2015
       Climate denial linked to conspiratorial thinking in new study
       

       Philippe,

       Sure.  Can you suggest an appropriate thread? I can't seem to find one.  Might I suggest that one of your authors find a reference for sensitivity as a function of temperature, write an article about it and then we can have a place to discuss this.  It seems to me that such a reference must exist somewhere, I just can't seem to find it and your authors should know more about what is out there then I do.

       Thanks,

       Michael

28132. tmbtx at 05:59 AM on 9 July 2015
       Carbon cycle feedbacks and the worst-case greenhouse gas pathway
       

       Ranyl - I still have some hope. Maybe that's just the part of my brain rationalizing the recent purchase of a home in Holland... 

       I'm not following though how switching to renewables will add to a carbon debt. Seems like it would be a net positive change. 

28133. PhilippeChantreau at 05:43 AM on 9 July 2015
       Climate denial linked to conspiratorial thinking in new study
       

       Gentlemen, this is kind of OT and should be taken to he appropriate thread, as usual.

28134. MIchael Fitzgerald at 05:37 AM on 9 July 2015
       Climate denial linked to conspiratorial thinking in new study
       

       MA,

       The zero feedback sensitivity I used is the slope of the Stefan-Boltzmann Law as this would precisely quantify the relationship between temperature and incremental input (forcing) for a planet with no GHG's or clouds in its atmoshere (i.e. no feedback).  As for feedback, I don't even account for that at 1K, so the actual sensitivity at 1K must be even higher than 65C per W/m^2, making the situation even worse.

       Your equation seems to assume that dT/dF is linear which can't be true based on the requirements of Stefan-Boltzmann.  Back to the original question, where can I find a plot of the sensitivity as a function of temperature?

       
       Perhaps a better way to pose the question would be that if the next W/m^2 of forcing increased the surface temperature by 0.8C what did the one before that do, the one before that and so on.  If I just divide the current surface temperature of 288K by its Planck emissions of 390 W/m^2 I get 0.74 C per W/m^2, however the relationship between temperature and emissions is far from linear (its a T^4 relationship), so I would expect a sensitivity closer to the slope of Stefan-Boltzmann at 288K which is about 0.2C per W/m^2.

28135. MA Rodger at 05:16 AM on 9 July 2015
       Climate denial linked to conspiratorial thinking in new study
       

       MIchael Fitzgerald @1.

       I'm not sure what sensitivity function you're using. The Stefan-Boltzmann Law does yield a rise of 65°C for the first W/sq m (actually 64.8°C). At 239 W/sq m, it yields a temperature of 255 K or -18°C which is, of course below freezing, this being the temperature of the atmosphere up where it radiates out into space, theoretically.

       Sensitivity (from the direct forcing alone) would presumably be 3.7 x  dT/dF =3.7 x d/dF ((5.67e-8 x F)^0.25) = 3.7 x 0.25 x 65 x F^-0.75 = 0.99°C. However, do note this is the sensitivity without any feedback mechanisms. With feedbacks the sensitivity is put in the range 1.5 °C to 4.5 °C according to IPCC AR5.

28136. wili at 05:10 AM on 9 July 2015
       2015 SkS Weekly News Roundup #27B
       

       Something to include in next weeks news roundup?

       www.esquire.com/news-politics/a36228/ballad-of-the-sad-climatologists-0815/

       Includes interviews with Box, Mann, Schmidt, and Parmesan, and lots of interesting insights into their (and our) emotional responses to our predicament.

       Moderator Response:

       [JH] I alerted my fellow SkS authors to the article yesterday and it will be included in the next posting of the Weekly News Roundup. I will also post a link to it on the SkS Facebook page. Thank you for bringing it to our attention.

28137. MIchael Fitzgerald at 04:01 AM on 9 July 2015
       Climate denial linked to conspiratorial thinking in new study
       

       Something the deniers say that troubles me is that the first W/m^2 of forcing results in a temperature of about 65K for a sensitivity of 65C per W/m^2 and that the Stefan-Boltzmann Law requires more forcing as the temperature increases, thus the sensitivity must decrease as the temperature increases which is consistent with the stated sensitivity of 0.8C per W/m^2 at the current temperature.

       The problem is that When I plot the sensitivity as a function of temperature starting at 65C per W/m^2 for the first W/m^2 ending at 0.8C per W/m^2 forcing at 239 W/m^2 (the total forcing from the Sun at the defined sensitivity) and integrate across all 239 W/m^2 of forcing, the surface temperature I end up with is higher than the boiling point of water. I simply can not find any reasonable function for the sensitivity as a function of temperature that produces the correct temperature based on the constraints on the sensitivity.

       My question is what is the sensitivity as a function of temperature? I
       haven't been able to find this in any of the literature.

28138. ranyl at 03:20 AM on 9 July 2015
       Carbon cycle feedbacks and the worst-case greenhouse gas pathway
       

       Howardlee and Tom C,

       The ocean will take up CO2 from pulse but over a long time though, the graph is misleading, look at the X axis on those graphs and that is in a very hypothetical situation were CO2 releases just entirely stop into the atmosphere.

       If we stopped all fossil fuel emissions tomorrow CO2 levels would still rise from land use, permafrost melting, forest fires (also not in IPCC) and the land sinks becoming acute sources as vegitation shifts and we have at least 0.5C warming to come, and in general warming tends to cause the releass CO2 in all the last Ice ages, most likely due to Southern Ocean linked mechanisms.

       Then everyone talks about grand children when the climate right now is quite literally becoming very extreme everywhere, so the impacts are now not tomorrow or in several decades.

       Then the question is how long does it take to get to equlibrium temperature?

       Hansen and others say 80% in 100 years, and ~99% in 1000 years.

       CO2 now ~400ppm.

       Last CO2 400ppm was the early Pliocene and Miocene, 3-5C to 4-6C warmer respectively.

       And people somehow claim we have a carbon budget; isn't this a debt situation?

       And if this is a debt situation, isn't replacing all the power supply with renewables and cars with electricity merely going tp add to that debt.

       That is if there is no CO2 budget, but a debt, then anything that requires CO2 emissions to make it is merely adding to the debt, even if it does slow the rate of debt accumulation in the long terms as fossil fuel usage is reduced. And at present all renewables carry a CO2 cost, and a significant biodiversity cost as well (mining rare earth metals, toxic wastes, mining steel, concrete, aluminium, solvents, etc,etc,etc), and soberingly we are in a rapid mass extinction and climate change is only just taking hold.

       Hope, is there hope?

       Unless we get CO2 below 350ppm by 2100, 2C is inevitable and considering the extremes we are already having how can that be at all safe?

       How?

       350ppm by 2100 given only 60% warming materialised gives 1.8C still.

       A 2C rise is a 5-SD shift in the world's mean temperature (using natural variation for the last 2000 years), and that is like increasing the average height of men by 15inches, extremely extreme.

       And it is becoming more and more apparent that in terms of weather there are other influences that are making things even more extreme that just a shift in temperature might be expected to produce, like Arctic rapid warming, the front ending of deluge events resulting in greater peaks of flow to exacerbate flash flooding and so on and on.

       Therefore as the climate dramatically shifts before our eyes we pretend there is room to move.

       And we locked into at least another 10 years of higher than 1990 emissions?

       And there are things like, New York is unsustainably vulnerable to sea level rise and storm surge increase, yet is anyone saying lets move?

       Florida?

       Venice?

       Shanghai?

       Bangladesh?

       Anyway lets hope the ocean do perform a miracle as Tom suggest for it is hard to see any other way out of this as even letting the mobile phon eis too great a sacrifice to anyone I've asked.

28139. Rob Honeycutt at 03:14 AM on 9 July 2015
       2015 SkS News Bulletin #6: Pope Francis & Climate Change
       

       Tom @63... That may be true in the northeast of China where it gets much colder than Chongqing, I'm not really sure. But if you look at early traditional homes in China, there is a cultural element that is very different from western culture.

       

       Whereas westerners build their homes around a central fireplace, these courtyard style arrangements are found in some remarkably colder regions in China. The central courtyard is (obviously) open, and all the various rooms surrounding the courtyard are generally very open as well, with lattice work for window coverings and such. I think much of that carries through into the culture today.

       The few rural homes I've visited in China were all very open. Even the kitchen, which is a room generally separated from the main living structure, still had no door and had open windows in the winter. It's just a big food prep room with a fire and one massive wok for cooking.

28140. ryland at 02:43 AM on 9 July 2015
       2015 SkS News Bulletin #6: Pope Francis & Climate Change
       

       My apologies.  In the interests of clarity I should have written "If someone you love dearly receives it the exact emotional cost to you is total emotional devastation.

28141. ryland at 02:41 AM on 9 July 2015
       2015 SkS News Bulletin #6: Pope Francis & Climate Change
       

       Tom Curtis @59  In response to your comment:

       "Come to that, what is the exact emotional cost of an excessive dose of anaesthetics? Please elucidate"  

       If you receive such a dose the exact emotional cost is none as you'll be dead.  If someone you love  dearly receives it the exact emotional cost is total emotional devastation.  I trust that elucidates sufficiently.

28142. howardlee at 01:55 AM on 9 July 2015
       Carbon cycle feedbacks and the worst-case greenhouse gas pathway
       

       Tom Curtis @ 8 - I was referring to the work of Zeebe & Zachos who were looking at the PETM compared to today. Most people estimate the rates of carbon release in the PETM were much slower than modern rates. But the recovery curve is broadly similar to Archer's figure you post. Here's a relevant figure:

       

       Regarding strong ocean absorbtion continuing for centuries, I'm simply highlighting research that may not apply to us. In addition to the Randerson et al paper there are others reporting the same thing such as this, and this.

28143. Alexandre at 01:19 AM on 9 July 2015
       Carbon cycle feedbacks and the worst-case greenhouse gas pathway
       

       Sorry, on my post above I meant a warming of 20 ºC over land.

28144. Alexandre at 01:17 AM on 9 July 2015
       Carbon cycle feedbacks and the worst-case greenhouse gas pathway
       

       IPCC scenarios do not convey the full gravity of the situation. They are usually limited to 2100 and people tend to think that 4.9 ºC (projection for RCP8.5) is the worst that can happen, bad as it is.

       It is plausible to assume that we're not leaving any fossil fuel underground. We are going to sell it and burn it to the last dollar, if we just continue our business-as-usual behavior. Try to talk seriously with any politician or executive of the fossil fuel industry about giving up available oil or coal.

       If we burn it all, and considering long-term climate sensitivity, we'll eventually pour enough CO2 in the atmosphere to reach about 20 ºC over land (reference below). This pathway we're in is tantamount to destroying the planet we live in. That's not something people gather from reading the mild-mannered IPCC report.

       Hansen 2013: Climate Sensitivity, Sea Level, and Atmospheric CO2

28145. howardlee at 01:08 AM on 9 July 2015
       Carbon cycle feedbacks and the worst-case greenhouse gas pathway
       

       tom Curtis @ 5 - OK I'll grant you nobody is talking of Venus-style, ocean-boiling runaway greenhouse. My point was that the paleo record shows several abrupt, strong global warming episodes.

28146. Tom Curtis at 23:54 PM on 8 July 2015
       Carbon cycle feedbacks and the worst-case greenhouse gas pathway
       

       howardlee @6, the consensus view on ocean uptake is represented schematically by David Archer thus:

       

       From memory, this is for a 1000 Petagramme pulse of CO2.  As you can see, the oceans keep on absorbing CO2 strongly for several hundred years after the pulse, eventually absorbing around 80% of CO2, before chemical weathering of different sorts eventually, and very slowly removes the rest (over hundreds of thousands of years).

       The models showing this pattern have successfully retrodicted the decline in CO2 concentrations following the PETM, so it is highly unlikely that they will fail for the CO2 increase expected over the next few hundred years with BaU.

       Yes, some scientists think differently, but they are a distinct minority.  It makes no more sense to work on the assumption that they are right than it does to work on the assumption that that other distinct minority much loved by Anthony Watts are right.

28147. Tom Curtis at 23:35 PM on 8 July 2015
       Carbon cycle feedbacks and the worst-case greenhouse gas pathway
       

       howardlee @5, a runaway greenhouse effect is when the Climate Feedback Paramater, α, approaches zero.  The Climate Feedback Parameter is defined by the IPCC:

       "Formally, the Climate Feedback Parameter (α; units:
       W m–2 °C–1) is defined as: α = (ΔQ – ΔF)/ΔT, where Q is the global mean radiative forcing, T is the global mean air surface temperature, F is the heat flux into the ocean and Δ represents a change with respect to an unperturbed climate."

       Here is one of the diagrams from the post to which I previously linked:

       

       In this diagram, the difference between the green line (representing the OLR prior to any forcing) and the red line (representing the OLR after a forcing is applied) is the change in OLR required to reach a temperature equilibrium.  As you will note, the y axis is in W/m^2, and the x axis in degrees K, meaning the instantanious slope of the blue line is the Climate Feedback Parameter for a given GMST.  As the slope approaches zero, you require a larger and larger temperature response to achieve equilibrium until, eventually, the temperature response to achieve equilibrium is greater than that consistent with liquid water on the Earth's surface.

       In simpler terms, the Cimate Feedback Parameter is the inverse of the Climate Sensitivity Parameter, λ, which is defined by the IPCC:

       "The climate sensitivity parameter (units: °C (W m–2)–1) refers to the equilibrium change in the annual global mean surface temperature following a unit change in radiative forcing."

       Fairly simply, as α approaches zero, λ approaches infinity.  So, a runaway greenhouse effect is that condition in which, until the oceans boil dry, climate sensitivity is for all practical purposes infinite.  Neither of the two posts you link to suggest evidence of this state, nor even use the term "runaway greenhouse effect".

       With regard to the "long tail", I clearly discussed the long tail of climate sensitivity, ie, the extended tail of the Probability Density Function of climate sensitivity as estimated using some statistical methods.  It has nothing to do with the long duration until equilibrium climate sensitivity is reached.

28148. howardlee at 23:34 PM on 8 July 2015
       Carbon cycle feedbacks and the worst-case greenhouse gas pathway
       

       I hate to add to the pessimism but there is evidence that the oceans, which have been "scrubbing" about 28% of our CO2 for us, will decline in their capacity to do this. In a recent study, Randerson et al showed that the ocean feedback will overtake the terrestrial feedback by the end of the century. This is because as the ocean warms it resists uptake of CO2, and a warming ocean reduces circulation, which diminishes the ability to refresh the saturated surface ocean with deeper water. A slowed biologic "pump" from sluggish, hot, acidifying oceans may also be a factor.

       In other words, the oceans will effectively amplify our emissions in the coming decades, over and above all the worst case scenarios mentioned in this article.

28149. howardlee at 22:48 PM on 8 July 2015
       Carbon cycle feedbacks and the worst-case greenhouse gas pathway
       

       Tom Curtis @2. Paleoclimate indicates that at geologically short timescales the climate can in fact do the equivalent of a runaway greenhouse - for example the end-Permian, end-Triassic, Capitanian etc. When CO2 rates overwhelm the terrestial and surface ocean sinks the Earth can undergo rapid, lethal warming. For example see this post and this post.

       The rock weathering thermostat does indeed prevent a runaway greenhouse over timescales of millions of years - but that doesn't prevent centuries-multi-millennia-length abrupt warming events which have happened several times in Earth's past.

       On the long tail, again paleoclimate does indicate a very long tail of 10s to 100s of thousands of years for anthropogenic climate change. For an article on that topic see this post.

28150. tmbtx at 16:00 PM on 8 July 2015
       Carbon cycle feedbacks and the worst-case greenhouse gas pathway
       

       Tom - I specifically am referring to the behavior of the climate system. Even more specifically I'm referring to how gaps in the understanding seem to turn out a bit worse than best guesses. There is nothing strange about this as scientists are usually cautious in their conclusions and making guesses without sufficient study. I suppose finding that we won't likely turn into Venus is a good thing, but the geologic record seemed to make that pretty clear to begin with. Certainly there are good things in our response with regards to renewable energy, etc. I'm not saying we're all dead and that there's not hope (well not most days) but that the size of the problem seems to grow a bit with each incremental advance. Concluding that our supposed worse case scenario is a lot easier to reach than previously believed is consistent with that.

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