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Comments 201 to 250:

  1. Philippe Chantreau at 03:10 AM on 28 April 2023
    At a glance - The greenhouse effect and the 2nd law of thermodynamics

    I'll take crack at the 3laws of thermodynamics, although I am only quoting:

    1- You have to play

    2- You can't win

    3- You can't break even

  2. Why the food system is the next frontier in climate action

    The last paragraph indicates population is expected to grow by 50 to 110% over the coming decades, and yet we can abate 55% or more of anticipated warming. Does the 55% abatement mean 55% abatement of per-capita emissions or 55% of total emissions for a baseline year of something like 2022? IF this is 55% abatement of per-capita emissions, then it would seem that population will grow as fast or faster than we can reduce per-capita emissions, so that the net ag-related emissions will continue to grow. Or am I missing something?

    Do the authors have an estimate for baseline, per-capita GHG emissions (quantified in CO2e) in a world where we do all the right things to reduce ag-related emissions?

  3. At a glance - The greenhouse effect and the 2nd law of thermodynamics

    Not bad at all, although a key aim of these mostly short intros is to explain and fully introduce stuff - therefore the need to explain what thermodynamics is. Many folk "out there" do not know what the word means. Some rebuttals are therefore much easier to write in a very short fashion than others.

  4. At a glance - The greenhouse effect and the 2nd law of thermodynamics

    My quick version of "at a glance" in about ten lines:

    "A climate myth claims that greenhouse gases cannot warm the earth because the flow of energy is from cold greenhouses gases to a warm surface, and this violates the second law of thermodynamics, which states that energy can only flow from hotter to colder objects (unless energy in some form is supplied to reverse the direction of heat flow).

    However the CO2 is not generating heat. It acts like a blanket to slow the transmission of heat energy from the surface and  in the atmosphere to colder space. The energy still transmits from hot to cold, just less heat at a  slower rate, so the second law is not violated. By analogy, if greenhouse gases violated the second law a blanket would not keep you warm."

    (Its based on memory of an explanation on a page. Its rough and needs refining, and I do not claim to have much scientific expertise, but I believe the essentials are there in about ten lines.)

  5. At a glance - The greenhouse effect and the 2nd law of thermodynamics

    If any of you want to have a go at explaining why the greenhouse effect does not invalidate thermodynmaics #2 in ten lines, including (essential) an introduction to what rule #2 actually says, then feel free to have a crack at it!

  6. At a glance - The greenhouse effect and the 2nd law of thermodynamics

    I tend to agree with Wilddouglascountry. The at a glance section was quite long. When I see "at a glance" I was hoping for a clear statement in ten lines. If a rebuttal cant be summarised clearly in ten lines, then the rebuttal probably isn't valid. Although clearly AGW and the greenhouse effect doesn't violate any laws of thermodynamics.

  7. At a glance - The greenhouse effect and the 2nd law of thermodynamics

    Note: the link to the full rebuttal is also included in the green box at the top of this post...

  8. At a glance - The greenhouse effect and the 2nd law of thermodynamics

    Wild (may I call you Wild?):

    This "At a Glance" version is intended to be brief. Although in this page, you only see the "At a Glance" part, the entire SkS rebuttal is available from the last link in the "Click for further details" section. This "At a Glance" has been added to the "Basic" tab in the full rebuttal (which also has an "Intermediate" tab).

    Short link from above:

    ...leads you to the long link of the actual page.

  9. wilddouglascounty at 23:52 PM on 26 April 2023
    At a glance - The greenhouse effect and the 2nd law of thermodynamics

    I took a gander at the 2010 TonyWildish original version of this and think that the revision you are offering here is a bit too dumbed down. Wildish and the related comments goes into the details of the dynamics of heat loss a bit more in-depth than your new version, while the new version focuses more on the paper that has been the source of disinformation on this topic, then says it is wrong without discussing enough the important physical details of heat loss/retention that make it wrong. I think the revision needs a bit more of those details; otherwise it's just a "they are wrong" argument without enough "why's" to really get to the heart of their mistakes.

    And by the way, please consider this to be my "form" that you asked feedback to be submitted by, since I didn't. I presume you look at the posted comments as well...

  10. One Planet Only Forever at 12:46 PM on 26 April 2023
    Drastic climate action is the best course for economic growth, new study finds

    I am pleased to see more economists are developing a more comprehensive and realistic accounting of the ‘current day costs of being less harmful’ and ‘the future costs of harm done by harmful current day activities’. Economic evaluations of the ‘perceived current benefits obtained from causing increasing future climate harm’ vs. ‘reducing the harm done’ needed to move away from the Nordhaus style of significantly discounting the ‘future harm done’ toward the more ethically sensible Stern style of evaluation which, by using a lower discount rate, is more concerned about harm done to future generations.

    “The Choice of Discount Rate for Climate Change Policy Evaluation” is a 2012 Discussion Paper that comprehensively presents the case for using lower discount rates. Longer term evaluations require lower discount rates, especially if there are harmful future consequences. Quotes from the paper and related points:

    In the Introduction “Using his own DICE model, Nordhaus indicated that the differences between the Stern-endorsed and Nordhaus-supported discount rate accounted for all of the difference between the more aggressive climate policy endorsed by Stern and the considerably more modest effort supported by Nordhaus.” The Stern-endorsed discount rate was 1.4%. The Nordhaus-supported discount rate was 4.3%.

    In 3a. The Social-Welfare -Equivalent Discount Rate “The choice of ‘social welfare discount rate’ is largely, if not entirely, based on ethical considerations: how much future well-being should count relative to current well-being in the social welfare function.” The Stern evaluation used a 0.1% social welfare discount rate. The Nordhaus evaluation used a 3% social welfare discount rate.

    Even the evaluation discussed in this article is from the perspective of a less ethical economic evaluation that is limited to the financial items that are easy to quantify and enter into the ‘economic models’. An example is the statement that “Achieving such rapid decarbonization would require climate policies commensurate with a global carbon price of about $250 per ton of carbon dioxide today but declining to below $40 per ton in 2100 as the prices for clean technology come down.” There is no ethical reason for high carbon prices to be reduced in the future. The ethical requirement is for the harmful impacts to be ended, not to have them continue to be in the competition for popularity and profit in an ‘economically fair way’. (Note: even the 2012 paper I linked to above is 'ethically neutral' even though it presents the case for using lower discount rates which is more aligned with ethical considerations).

    It is simply unethical for ‘Some people’ to benefit from causing harm that ‘others’ experience and have to try to deal with and repair. A continuously increasing price on carbon is one of the many mechanisms that need to be imposed to achieve the required correction of harmful developed activity, especially the correction of developed popularity and profitability of harmful over-consumption. And a Zero discount rate, and potentially a negative discount rate (increasing the evaluated cost of future harm being created), is probably more appropriate.

  11. 2nd law of thermodynamics contradicts greenhouse theory


    Discussions of extreme events are probably better placed on this thread (after reading the original post):

  12. Rob Honeycutt at 04:12 AM on 26 April 2023
    2nd law of thermodynamics contradicts greenhouse theory

    Gootmud @1522... There is an entire body of research related to precisely this topic known as attribution research. Your lack familiarity of the science shouldn't lead to the conclusion that "we can't explain causally." On the contrary, the overall causality of the shift in distribution is extremely well-known. The only place uncertainties appear are the chances that any given indivual weather event is driven by human causation. But even there, attribution research is demonstrating increasingly how much more likely these are to be primarily a result of the rise of CO2 concentrations in the atmosphere.

  13. 2nd law of thermodynamics contradicts greenhouse theory

    Gootmud @ 1522,

    Hot weather tends to be associated with a high pressure system situated in a position to a) allow maximum insolation and b) to permit warm air advection. That's not "some random process". With global warming, in the synoptic situation I describe, it can be expected to be a bit hotter again. This should not be too difficult to visualise.

  14. 2nd law of thermodynamics contradicts greenhouse theory

    Also note that this conversation is getting of the proper topic, which is the 2nd Law myth.

  15. 2nd law of thermodynamics contradicts greenhouse theory

    Gootmud @ 1522:

    The diagram and explanation provide does not at all mean "some random process we can't explain causally". We can explain variation about the mean. It's called weather.

    If you think that every single normally-distributed measurement is a purely random process, you need to think again.

  16. 2nd law of thermodynamics contradicts greenhouse theory

    Rob @1520...that looks like "climate does weird things" presented as a graph. It suggests heat waves are the result of some random process that we can't explain causally.  We can only talk about the distribution, and we expect that as the mean shifts the tails will shift along with it. That contradicts the idea of attribution.

  17. 2nd law of thermodynamics contradicts greenhouse theory

    Gootmud @1518:

    The 2C rise does not cause the 20C heat spike, it turns an 18C heat spike into a 20C heat spike. Rob's diagram @1520 shows this shift in the overall distribution.

    Rob's diagram also assumes that the spread around the mean remains constant. This may or may not be the case, and may vary locally. Another plausible scenario is that a location used to go +/-16C from it's mean, and now it goes +/-18C around its new mean that is +2C, so +20C (from the old mean) is the result of a 2C shift in the mean, and a +/-2C expansion around the mean. The +20C spike compares to a system that only saw +16C in the past.

  18. Rob Honeycutt at 00:52 AM on 26 April 2023
    2nd law of thermodynamics contradicts greenhouse theory

    And here is a simple graphic explaining it as well.

  19. Rob Honeycutt at 00:50 AM on 26 April 2023
    2nd law of thermodynamics contradicts greenhouse theory

    Gootmud @1518... Probably the best way to understand this is to watch what happens over time with the shifting distribution of temperature events. Here is a great animated graph from the NASA Scientific Visualization Studio.

  20. 2nd law of thermodynamics contradicts greenhouse theory

    Seems to me the main paradox between AGW and the 2nd law of thermo is not about radiation transfer but about attribution.  The greenhouse effect says higher average CO2 over decades causes higher average temperatures. But how does a 2°C temperature rise over a century cause a 20°C heat wave for a week in Toronto? Humans have gotten a bit taller over the past century, but no one would consider that a satisfactory explanation of a village where everyone is 8 feet tall.

    As summer arrives in the northen hemisphere, we're due for another season of news stories that claim such causality without asking whether it makes any sense.  Was CO2 especially dense in Toronto that week?

    One can obviously handwave that Earth is a heat engine not constrained by the 2nd law, or that climate is a chaotic system that does weird things we can't explain, but that undermines the claims we can attribute the heat wave to anything in particular.  Or one can point to computer simulations where similar weird things happen, but that just relocates the paradox from Toronto to SimToronto.

  21. Cranky Uncle earns 2023 IILP Annual Best Publication Award

    Great job John and company. A real win for truth.

  22. Rob Honeycutt at 09:25 AM on 22 April 2023
    There is no consensus

    Okay, let's go over this again, Albert.

    The premise of the paper is as stated in the introduction. 

    We examined a large sample of the scientific literature on global CC, published over a 21 year period, in order to determine the level of scientific consensus that human activity is very likely causing most of the current GW (anthropogenic global warming, or AGW).

    Do you honestly not see the words: human activity is very likely causing most of the current AGW?

    That statement creates the fundamental basis of papers that either endorse or minimize that position.

    If you're telling me that most "skeptics" agree that human activity is very likely causing most of the current GW... hey! We're good!

    "It is a clear indication that only 1.6% of the papers thought that humans were causing most of warming."

    Nope, precisely because categories 1, 2 and 3 all endorse the idea that human activity is very likely causing most of the current GW.

    "...AMS in 2016 and it explicitly asked members if they vpbelieved humans were responsible for the majority of warming and 67% said yes."

    And they also explain that most of their members were NOT experts in climate science and do not publish climate research. The greater their expertise, the greater their level of agreement, with the highest level of expertise also demonstrating ~97% agreement with the idea that human activity is very likely causing most of the current GW.

    "...why Cook went to considerable lengths to hide the category numbers."

    He didn't.

    "I am passionate about truth in science..."

    Clearly, quite the opposite.

    "...I have an open mind on all matters..."

    As Carl Sagan used to say, "It's good to keep an open mind, but not so much that your brain falls out." I think that perfectly describes your position in this matter.

    "In the sixteenth century, 99.9% of scientists believed the Sun orbited the Earth."

    No, it was 16th century scientists who were explaining to people the earth orbited the sun. Once presented within a scientific/mathematical structure, scientists of the day readily accepted this fact. 

    "i Won't be commenting on this thread again."

    We are relieved.



  23. There is no consensus

    "a) If you had bothered to read the actual paper it's explained why the figures are organized as they are."

    I have read the paper multiple times and the so called explanation groups 1,2 and 3 together and compares them to groups 5 6 and 7 and as I have said, most sceptics would be in group 3.

    The "minimise" option Is a red herring as most sceptics believe in an ECS of 1.2C which is both group 3 and groups 56 and 7.

    "b) Your 1.6% figure only relates to papers that explicitly quantify human contribution. With that you'd have to compare that to other papers that explicitly minimize human contribution."

    Nonsense. It is a clear indication that only 1.6% of the papers thought that humans were causing most of warming.

    You can't count, for example, a paper that explicitly quantifies against a paper that implicitly endorses human contribution.

    Nomsense. Most sceptics who write papers would be in several categories and that is the lie in Cooks paper.

    The only time that a scientific organisation has polled its members was by the AMS in 2016 and it explicitly asked members if they vpbelieved humans were responsible for the majority of warming and 67% said yes.

    They didn't play the pretend game of setting up false categories and compare warmists against sceptics like Cook did.

    The AMS were extremely embarrassed by this and tried to spin the result saying it was misinterpreted blah blab blah but since this no scientific body has ever dared poll their members again.

    Roh you still havenot explained why Cook went to considerable lengths to hide the category numbers. It took me a couple of days to eventually figure out how to chuck the file into a spreadsheet and extract the totals.

    I am passionate about truth in science, you're not, so let's just agree to disagree. 

    PS engaged with you on this subject because I have an open mind on all matters and wanted to read whether there were aspects of the "97%" I wasn't aware of, but your comments show me that there aren't.


    Last comment 

    A few years ago the Australian sceptic society had a comment on their home page saying nothing was exempted from scepticism but also had a manifesto on global warming saying the science was settled and gave theit reasons.

    I went through the manifesto line by line discrediting it by referring to data and submitted it. However next day it had disappeared and I contacted the editor and he said he had passed it on to "experts" to see if it was valid. He said he would get back to me but never did.

    So a sceptic society now determines what you can be sceptical about. You can challenge the theories of Newton and Einstein but not the high church of climate change. That makes it a faith, not science.

    Very last comment

    In the sixteenth century, 99.9% of scientists believed the Sun orbited the Earth.

    i Won't be commenting on this thread again.




    Moderator Response:

    [BL] Points previously made, previously refuted, all marked with warning snips. If there had not already been a response, the entire post would have been deleted as sloganeering.

    As this user is incapable of reading, understanding, and/or following a comments policy, the only thing we can agree on is that this will be his last post - on this thread, or any other.


  24. It's not bad

    This doesn't seem to help!  

    "Climate news can seem dire with little hope for a better world. Talk to climate scientists, engineers and researchers, however, and they see a different future – a positive one that's well within our reach.

    For Earth Day 2023, instead of imagining the worst, USA TODAY invites you to envision the best. Conversations with a dozen experts give a glimpse of what a time traveler from today might see as they experience life a generation from now in a United States that put its mind to solving climate change – no miracles or as-yet-uninvented technology needed."

    Is everything really coming up roses? I thought in order to keep temperatures below 1.5 degrees C it would require technology that can take massive amounts of CO2 from the atmosphere and finding a place to store it. If we let it go to 2 degrees C, can we relax?

  25. prove we are smart at 20:06 PM on 21 April 2023
    EGU2023 - Upcoming presentations in Vienna

    Thanks for your thoughtful reply, it isn't often ( well in my information world) I hear even a little of good about Davos and the WEF. You know I believe in the inherent good in people and people can change.

     But I feel like I am constantly on a seesaw-occassionally balancing evenly-a little down and losing some hope to a little up and we'll muddle through. But the last few years have seem me sink way down and no corresponding way up to match.

    Yes I agree with your statement "(SkS can be understood to have been formed in response to the successful misleading marketing by conservative populists trying to preserve and grow their undeserved perceptions of status and superiority)."

    As Prof Anderson asks " Will it be a velvet revolution or a violent revolution?" I believe that is coming, it was coming anyway with the widening inequality, climate disruption has sped it up and will spread it more.

    Perhaps the harmful media ( sometimes contolled by or controlling those populists) can be called out. Then the majority may be ruled by politicians that believe "life is about planting trees under whose shade you will never get to sit" My seesaw may swing up, perhaps my lucky Australia will go with the former then-i think the larger the percentage of homeless and less resilient citizens, the more the latter will dominate-spilling over to their neighbouring countries.

    In this age of misinformation and forgotten morality, we NEED this to happen, from our IPCC-  "Targeting a climate resilient, sustainable world involves fundamental changes to how society functions, including changes to underlying values,worldviews, ideologies,social structures,political and economic systems and power relationships."

    That is a revolution in every way possible-bring on the leaders and media that can wake us up to a velvet one..


  26. One Planet Only Forever at 14:53 PM on 21 April 2023
    Arctic sea ice has recovered

    Albert started an interesting discussion with their comment @120.

    I have an update of my questioning comment @124.

    My updated question for Albert is "What explains the recent reduced rate of Arctic Sea Ice loss given that global ice mass loss has continued to occur?" (in addition to the links @124 see the EGU "Review article: Earth's ice imbalance" here which has the following in its Abstract "The rate of ice loss has risen by 57 % since the 1990s – from 0.8 to 1.2 trillion tonnes per year")

    Similar to my question @124, the answer is not that human impacts have stopped significantly affecting the climate. And, as has been painstakingly pointed out by others, the recent lack of rapid reduction of Arctic sea ice does not mean that the recent rapid reduction of Arctic sea ice due to human induced global warming has ended.

    That raises another question. "Why is the admittedly unusual temporary reduction of the rate of Arctic Sea Ice loss being focused on so relentlessly when global ice loss has continued to occur rapidly?"

  27. One Planet Only Forever at 07:40 AM on 21 April 2023
    EGU2023 - Upcoming presentations in Vienna

    prove we are smart,

    I agree in general with your comment and the presentation by Prof. Kevin Anderson, University of Manchester you linked to. The following is in response to the question you ended your comment with.

    I would caution against simplistically claiming that ‘the 1%’ or ‘the Davos WEF group’ are ‘the problem’. The fundamental problem is the success of more harmful Populist political game players (Note: Populism is fundamentally misleading, but some of the misleading political players are less harmful regarding climate change). Refer to the SkS re-posting of the Thinking is Power item “Science and its Pretenders: Pseudoscience and Science Denial” and my comment @6 on that posting. (SkS can be understood to have been formed in response to the successful misleading marketing by conservative populists trying to preserve and grow their undeserved perceptions of status and superiority).

    Not all of the wealthiest 1% are the problem. The problem is the harmful populist portion of the wealthy and the supporters they have gathered by being misleading about climate science and the required rapid changes of what has developed (note that the harmful populists are harmfully misleading about many matters, not just climate change). And harmful populist people can be found to different degrees in almost every nation, not just the richest and highest climate change impacting nations.

    It does appear that the Davos WEF group are doing less than they could to reduce the climate change harm done (they harmfully compromise what could be done). So it is fair to point that out. But I have noticed that the harmful populists currently claim that the Davos WEF group are a threat because of the climate impact restrictions that are being discussed by that group. The conservative populists want more freedom, especially more sovereignty for regions they control to be as harmful as they please. They oppose the ‘globalist progressive improving understanding’ that has been developed collaboratively and collectively globally (like the IPCC results, the Sustainable Development Goals, or the Universal declaration of human rights). Their opposition is due to the reality that the understood actions required to develop sustainable improvements for humanity, to be less harmful and more helpful, require significant changes of their developed preferred beliefs and ways of living.

    In closing and responding to: “Is dangerous climate change not really dangerous for the 1%?”

    People focused on the pursuit of status relative to others can indeed not consider harmful consequences to be dangerous ‘for them’, especially if they believe those harmed have little ability to ‘do significant harm in return’. And that attitude can exist at all levels of wealth and status. And it is especially true regarding ‘future harmful consequences’ like the type created by accumulating climate change impacts. And those future consequences can be less of a concern if there is ‘doubt about the harm being caused’. Hence the harmful success of populist political players promoting ‘Big Lies’ and ‘Alternative Facts’.

  28. Skeptical Science News: The Rebuttal Update Project

    The blog post was updated on Apr 20 with the link to the latest rebuttal getting the "at a glance treatment": Positives and negatives of global warming

  29. It's not bad

    Please note: the basic version of this rebuttal has been updated on April 20, 2023 and now includes an "at a glance“ section at the top. To learn more about these updates and how you can help with evaluating their effectiveness, please check out the accompanying blog post @

    Thanks - the Skeptical Science Team.

  30. Rob Honeycutt at 00:46 AM on 21 April 2023
    Arctic sea ice has recovered

    Albert @150... I'm curious why you can't see what you're doing is selecting (cherry picking) short time frames out of a clear overall trend in order to fit a predetermined conclusion. 

    This is truly what I find so fascinating to witness. The sheer volume of well-established research and scientific evidence that has to be dismissed or ignored in order to come to such conclusions is staggering.

    Anthony Watts I can understand simply because his income is predicated on keeping climate deniers coming to his website. People who don't have a specific monetary necessity, these I don't understand.

  31. Rob Honeycutt at 00:35 AM on 21 April 2023
    Arctic sea ice has recovered

    Albert @149... So, I guess you're saying ice measurements before satellites weren't accurate unless you're trying to use pre-satellite ice measurements to reject research that you don't like. Right?

  32. Arctic sea ice has recovered

    Albert @151,

    If you start from 2003 you get a linear trend of -0.052M sq km/y, an even steeper decline.

    Perhaps to assist you in this exercise (which is presently somewhat akin to the children's game 'Pin the Tail on the Donkey'), may I point you at the excellent JAXA Vishop webpage which provides 'graph options' that include 'annual graph' and 'draw linear fitting lines from visible region'. This will show you that all trends in this data for periods ending 2022 are declining for start-dates prior to 2015. Given the wobbly nature of the data, using just eight data points, this same facility shows the data yields other instances of non-negative eight-point-long trends in this data so such a short period is entirely unrepresentative.

    Moderator Response:

    [BL] You're doing this wrong. You're not supposed to do actual statistical analysis on the data. If you look at the monthly values, not annual, there is a lot more noise, and you can then use your eyecrometer to just look at the graph (ignoring the "draw linear fitting" button), and then your Morton's demon will filter out any signal that shows a decreasing trend and you can convince yourself that it looks like 0 trend.

    (HTML badly needs a sarcasm tag.)

  33. Arctic sea ice has recovered

    I do look at JAXA data and it evidently has "decreased since 2006" in that the JAXA annual average SIE 2006-22 has a linear trend of -0.032M sq km/y"

    I was wrong, if you start from 2003 instead you will see that JAXA data linear trend shows 0 change.

    Moderator Response:

    [BL] So, to make your point, you start looking for outliers and cherry picking certain times to get the result you want? Classic use of the techniques illustrated in The Escalator (updated version).

    The Escalator 2022

  34. Arctic sea ice has recovered

    The Kinnard has Arctic ice extent increasing from about 750 to 1500 which is an absurdity. Vikings colonised Greenland about 980 and farmed some areas that today are permafrost.

    But the graph shows 980 ice extent to be about the same as 1700 and by that time the areas farmed were permafrost.

    The graph shows ice extent dropping dramatically from about 1400 but the little ice age was ramping up in 1400, not down.

    The graph shows ice extent increasing dramatically from about 1600 but the LIA peaked around 1650-1700 and temperatures have risen sporadically ever since. The Central England Temperature database correlates well with this.

    Here is a different reconstruction that shows 1940 Arctic ice to be about the same as 


    See figure 1b

    But the guy was italian and what would they know?  See, I can be sarcastic as well.

    Moderator Response:

    [BL]Link breaking page formatting shortened.

    Your Greenland myth is covered in this post.

    You have already been pointed to places where your poor understanding of the Medieval Warm Period is covered.

    You can correct your misunderstandings about the Little Ice Age by reading this post.

    The Van Achter reconstruction that you show uses climate model data fitted to recent sea ice data to extrapolate values into the past and future. They also state "The Canadian Archipelago region was removed from the dataset since SIT reaches unrealistic values in this area." They also state "For the variability analysis, the trend and seasonal cycle are removed from the time series (pan-Arctic SIV and gridded SIT)".

    Have you considered how this selection of data might influence the result? The authors have. In their conclusions, they state:

    This analysis of the Arctic SIT and SIV variability bears some limits. Indeed, our results for the temporal and spatial patterns of variability are based on only one model, and despite the use of 30 ensemble members and a reasonable validation against observations, the model is not perfect. Furthermore, the spatial modes of SIT variability are robust for all the 30 ensemble members, but the temporal analysis shows some dissimilarities between members. Other studies with other model outputs are therefore needed to confirm our conclusion.

    Given that you reject climate models entirely, I am surprised that you would be so convinced that a reconstruction based on one is the most reliable indicator of past sea ice conditions.


  35. Rob Honeycutt at 15:44 PM on 20 April 2023
    Arctic sea ice has recovered

    "...the trend has probably plateaued."

    And that is what we call a baseless assertion. 

  36. Rob Honeycutt at 15:42 PM on 20 April 2023
    Arctic sea ice has recovered

    "The graph above showing Arctic ice just shows reconstructions because there was no accurate way to measure total Arctic ice before satellites."

    Oh ye of little faith is the cleverness of smart researchers.

    Kinnard et al. (2011)

  37. Arctic sea ice has recovered

    Thanks for the insert advice, it was driving me bananas.

  38. Arctic sea ice has recovered

    finally managed to insert it.

    if you look at average extents, it can be seen that from about 2007 the trend has probably plateaued. 

    if satellites had been operating from 1940, the downward trend would be Far less.

    The most accurate extent measuring satellite is MASIE which measures in 16km2 blocks rather than the 225km2 blocks of SII and it shows Arctic extent plateauing from 2006.

    From memory I think JAXA and the University of Bremen have the plateau starting even earlier.

    Moderator Response:

    [BL] Here we see the effects of confirmation bias plus overconfidence in one's opinions. In spite of earlier saying "there was no accurate way to measure total Arctic ice before satellites." as a way of rejecting data covering the 1940 period that he does not like, Albert is now asserting his confident opinion that if such data existed, he knows what it would show.

    And again he inserts "has probably plateaued" instead of actually doing any sort of real statistical analysis.

    I expect Albert has also not noticed that the Arctic Ocean is surrounded by land, which severely limits the winter maximum ice extent. There are well-understood reasons why winter extent does not show as much variation as summer extent. But as long as Albert can average away the strong decline in summer extent - which disagrees with his confirmation bias - then averaging it will be!

  39. Rob Honeycutt at 15:36 PM on 20 April 2023
    Arctic sea ice has recovered

    I'll note that all the trend lines in both these graphs are showing ice loss. Anything on shorter scales, up or down, is merely noise. 

  40. Rob Honeycutt at 15:33 PM on 20 April 2023
    Arctic sea ice has recovered

    Also, be sure to check the image size on the "appearance" tab. Make sure to restrict the image to 500px width.

  41. Rob Honeycutt at 15:32 PM on 20 April 2023
    Arctic sea ice has recovered

    Second tab says "insert." See the picture of the tree? Click that and... voila!

    Your problem is that you need to have a direct link to the image, not just the page. Right click the image (control+click on a Mac), then select open the image in a new tab. Use that URL.

  42. Arctic sea ice has recovered


  43. Arctic sea ice has recovered

    I tried to insert a graphic from DMI showing Arctic ice extent from 1979 but without success.

    The URL shows a decline of about 15% from 1979 to about 2012 but unfortunately most warmists only refer to the minimum monthly values rather than all the data.

    Its like only giving January rainfall totals instead of the yearly totals.


    The graph above showing Arctic ice just shows reconstructions because there was no accurate way to measure total Arctic ice before satellites.

    I could show you reconstructions showing significantly different trends but I know it would be a waste of time.

    Moderator Response:

    [BL] Link activated.

    The web software here does not automatically create links. You can do this when posting a comment by selecting the "insert" tab, selecting the text you want to use for the link, and clicking on the icon that looks like a chain link. Add the URL in the dialog box.


    As for your assertion that yearly totals should be looked at, not January (for rainfall) - if the goal of an analysis is to look at crop production in Australia, then January precip is probably much more informative than annual totals.

    Any argument of "all the data" is usually bogus. For Arctic sea ice, you don't include seasonal ice cover in the tropics, either. You don't divide the ice area by total ocean area (or the area of the globe). Every scientific analysis requires the use of relevant data. You have not provided any argument as to the relevance of using annual totals.

    As for offering to show "reconstructions showing significantly different trends", you fail if you do not show that the "significantly different" claim is supported by actual, real statistical analysis. You know: the kind of things that real scientists do.


  44. Rob Honeycutt at 15:21 PM on 20 April 2023
    Arctic sea ice has recovered

    Albert @139... Would you like a quick tutorial on how to post images here?

  45. Rob Honeycutt at 15:18 PM on 20 April 2023
    There is no consensus

    If one thinks about how Albert is trying to frame this, it makes no sense. I've heard the same tripe from other deniers over the years; he's not the first to come up with this.

    He's trying to re-frame the question from "in order to determine the level of scientific consensus that human activity is very likely causing most of the current GW" into "in order to determine the percentage of research papers that endorse and quantify human contribution to GW as >50%."

    It's quite a nonsensical and pointless framing of his (their) own creation that bears no relevance to anything that would have the least bit of interest to anyone.

    Once again, it is fascinating to watch such entrenched, intractable displays like this. 

  46. Arctic sea ice has recovered

    linear trends have their uses but can be misleading and if the above trend had a 12 month filter, that would give a more realistic interpretation of Arctic ice trend.

    the start and stop times of linear trends can heavily influence what a trend looks like and the assumption that Arctic ice is on a permanent downward spiral rather than cyclic is just speculation.

    The end  of summer Arctic ice has been predicted regularly since 2006 by the top Arctic experts but it never eventuates. 

    Moderator Response:

    [BL] Your baseless assertion about predictions of the end of arctic summer ice needs to be backed up by specific references.

  47. Rob Honeycutt at 15:03 PM on 20 April 2023
    There is no consensus

    Albert... I think you should take a moment to read the comments policy for this site. Accusations as you've just leveled are against policy.

    As for your question, no one was trying to hide anything. The data is there available for anyone who wishes to dig into it. But it's not really relevant to the results of the paper. It just creates fodder for people like you whose intent is to misinterpret the data.

    Regarding the AMS paper, different from the Cook paper, that research was about the opinions of their members. As already stated, the paper was structured similar to Doran/Zimmerman where the subjects had varying degrees of expertise in the subject matter. Once you got to publishing PhD level scientists, yes there was a consensus in the 97% range.

  48. Rob Honeycutt at 10:29 AM on 20 April 2023
    There is no consensus

    @933... Missed this one: "The only 'evidence' for the positive feedback theory are models which are trying to model something where many variables are only guesstimates."


    Knutti and Hegerl (2008)

  49. Rob Honeycutt at 10:24 AM on 20 April 2023
    There is no consensus

    "But Michael Mann showed us in his model that the medieval warm period and little ice age never existed so all those thousands of scientists that proved they did exist must be wrong."

    a) Please look up the definition of the word "heterogeneous."

    b) Assuming you're talking about MBH98/99, that was nearly 25 years ago and their research only went back too the MWP. Perhaps you should catch up on more recent research.

    (Yes, this is quickly veering off-topic... as one would expect.)


    Moderator Response:

    [PS] Any further discussion on this thread that is not about the consensus will be deleted.

    [BL] Discussion of the Medieval Warm Period should go on one of these threads:


  50. Rob Honeycutt at 10:18 AM on 20 April 2023
    There is no consensus

    @934... "believe it or not there are other factors that effect global temperature like, the sun, solar winds, magnetic fields, cosmic rays...(etc., etc.)."

    This is starting to gish into a big gallop.

    If you're going to accept low CS figures then you also need to accept high CS as well, otherwise you're just cherry picking your preferred conclusions without considering the full body of research.

    There are good reasons to believe the high CS figures have low probability, as there are even stronger reasons to believe low CS figures are improbable.

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