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Comments 51 to 100:

  1. Mastering FLICC - A Cranky Uncle themed quiz

    Thanks to all who have played the quiz thus far!

    Some feedback comments mentioned that explanations are missing of why a selected answer is wrong. Unfortunately, that's a limitation of using a Google form as a quiz. It's only possible to provide one explanation for the correct and another one for all the wrong answers.

    However, all the cartoons with the respective fallacy definitions and examples are available in our graphics resource @ So, if you wonder why answers you gave are wrong, you can find out by scrolling down the list and selecting the "problematic" cartoon(s).

    Hope this helps!

  2. Skeptical Science New Research for Week #21 2024

    Michael Sweet @ 3:

    Technically, David-acct has not actually made any argument at all in comment 1. All he did is quote some numbers. We are left to speculate as to what argument he was trying to make. I agree that he was probably trying to make an argument along the lines of "oh, my, look at how huuuugely expensive this is!!!", to which the rejoinder is "compared to what?".You have pointed him in the direction of "what?"

    Maybe his argument was intended to be "look at how cheap this will be!!!", but I somehow doubt it. If David-acct's past commenting habits are a guide, I also doubt we'll see him return to be more specific or actually make a logical argument.

    My analogy to David-acct's "argument" is to compare him to a homeowner who has been told "Your roof is leaking badly. It will cost $20,000 to replace it." The homeowner balks at the cost, and decides not to do it. Meanwhile, he's doing $60,000 of renovations to upgrade the kitchen to granite counter tops and walnut cabinets, and has spent $40,000 to create a media room on the second floor, with flat screen TV, 7-channel sound system, etc.   ...and all those renovations get destroyed a few months later when the leaking roof causes major flood damage. He expects insurance to cover the cost, but when the insurance company finds out he was told about the leaking roof earlier and chose to ignore that advice, the insurance company says "you're on your own".

  3. michael sweet at 01:12 AM on 27 May 2024
    Skeptical Science New Research for Week #21 2024

    Sorry, my link in 3 is broken try

    Jacobson 2022 free

    Moderator Response:

    [BL] Same link problem fixed. There seems to have been some sort of "chrome-extension" text prepended to the proper link. Probably best to pass it through a plain text editor before copying and pasting.

  4. michael sweet at 22:39 PM on 26 May 2024
    Skeptical Science New Research for Week #21 2024

    Jacobson 2022 describes a completely renewable system for the USA including all transportation, all industry and all other energy used in society.

    I note that in Jacobson 2022 he models a system using renewable energy (primarily wind and solar but including hydro, geothermal and other minor sources) without any burning of anything.  Other proposed systems burn renewable sources like vegetable oil, forrestry waste and trash and are cheaper than Jacobson's system.  Jacobson argues that it is worth the extra cost to reduce pollution as much as possible.

  5. michael sweet at 22:26 PM on 26 May 2024
    Skeptical Science New Research for Week #21 2024


    And where you live fossil fuels are free?  You fill up your car for free?  Electricity is free?  Heating and cooling are free?   This is such a stupid argument that it is difficult to reply.

    You are like the teenager who tells his dad that a $30,000 Tesla is too expensive so he has to buy the Ferrari. (He doesn't mention that the Ferrari costs $200,000).

    Jacobson 2022 (free copy) states:

    "In the “Total USA” case, the 2050 BAU annual private energy cost is $2.5 trillion/yr, and the 2050 BAU annual social energy is $6.8 trillion/yr (Tables 4 and S20; Figs.5 and S3).   Thus, the private and social costs of WWS energy (both $933 billion/yr) are~63% and ~86% lower, respectively, than those of BAU"

    The energy costs alone of fossil fuels are 2.7 times more expensive than renewable energy (WWS in Jacobson).  Millions of people are killed every year by fossil pollution in your choice.  The social costs are about 7.3 times the cost of renewable energy. 

    Your argument about costs is simply ignorant bluster.

    Moderator Response:

    [BL] Link fixed

  6. Skeptical Science New Research for Week #21 2024

    ...or a little over $400 billion per year, or about $1300 per person per year.

    The US plans to spend nearly $900 billion this fiscal year on defence.

    I have to admit, David-acct, I am amazed at your ability to avoid seeing context.

  7. Skeptical Science New Research for Week #21 2024

    From the David Brown Wood MacKenzie article / link above


    Figure 1. US$11.8 trillion dollars in capital investment in US energy is required on a cumulative basis from 2023-2050 to reach our net zero scenario.


    The $11.8 Trillion dollars is approx $35,000 per person in the US or approx $72k-$75,000 per household.  


  8. CO2 is not the only driver of climate

    Please note: the basic version of this rebuttal was updated on May 25, 2024 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 @

  9. One Planet Only Forever at 13:45 PM on 23 May 2024
    2024 SkS Weekly Climate Change & Global Warming News Roundup #19

    A follow-up comment to my comment @1,

    This CBC News item: Small island states hail ocean court victory on greenhouse gases is evidence that the 'law and order' approach can work ...

    But there need to be more votes of support for helpful harm reducing law and order actions. More people need to choose to 'learn to be less harmful and more helpful to others' so that 'justified rule of law' can effectively limit the harm done by those who resist such learning.

    Competition for perceptions of status and reward can obviously powerfully compromise such helpful pursuits. These recent legal wins, like the recent increased actions to limit climate change impacts, have been diminished and delayed ... to the detriment of the future of humanity ... by the popularity and profitability of 'more freedom to believe and do whatever is desired'.

  10. One Planet Only Forever at 06:47 AM on 23 May 2024
    Climate Adam: Can we really suck up Carbon Dioxide?

    An extreme example of carbon dioxide removal greenwashing is the marketing of the glory of the Pathways Alliance plans to make Alberta oil sands production 'Net-zero by 2050' (see here for their self promotion details).

    As mentioned in Climate Adam's video, and the earlier CCS video he mentions (a link at the end of this Climate Adam video), CCS of oil sands operations will only keep part of the ghg impacts of the operations from entering the atmosphere, with risk of leaks of the stuff thought to have been captured and stored. In particular, any methane emissions are not captured for storage.

    So, to be 'net-zero' the Pathways Alliance will have to divert (consume) some of the 'real carbon removal activity' that will almost certainly be necessary to bring total human impacts back down to 1.5 C levels (human impacts are expected to exceed the globally agreed 1.5 C level).

    Pathways Alliance action, if they get subsidized to the degree they want and actually do something to reduce carbon emissions, would improve Canada's Climate Actions. But the most recent Climate Action Tracker evaluation of Canada linked here (pointed to by prove we are smart in this comment on another SkS item) is "Highly Insufficient" significantly due to leadership being compromised by being interested in profiting more from being more harmful and evading the costs of being less harmful. The Pathways Alliance improvement may only move Canada to "Insufficient" Climate Action.

    It appears the (Canadian, Alberta, oil sands investors) hope is that some fossil fuel use will be globally agreed to be needed after 2050 to exclusively provide essential assistance for the least fortunate to live basic decent lives. And they (Canada, Alberta and oil sands investors), being net-zero suppliers by then, should be globally supported to be the chosen suppliers.

    Harmful actions can only be justified if the harm is required to provide essential life assistance to the less fortunate (and it would be unacceptable for anyone to profit from providing that assistance - it should be not-for-profit).

    That raises many questions including:

    Will Canada, Alberta and oil sands investors all agree to be Net-zero-profit-takers after 2050?

    And will they have taken action and paid what it costs to minimize the need to divert 'real carbon removal actions' to offset their remaining impacts (diversion required so they can claim to be 'net-zero' suppliers of a harmful product)?

    And will they agree by 2050 that the only benefit from their 'net-zero product that will produce harmful impacts when used as expected' is to be obtained by the least fortunate (refusing to export it to questionable buyers)?

  11. prove we are smart at 22:44 PM on 20 May 2024
    Climate change is affecting mental health literally everywhere

    “Sometimes people report it’s not one feeling or the other,” Lawrance says. “They feel a lot of ways at once, and feelings can change day to day.” One day might bring a mix of fear, grief, anger, guilt, hopelessness, or numbness"

    Thats me-all of the above and I have to remind myself often-

    "There is no threshold past which we should stop trying to address climate change, according to climate scientist Michael Mann, who has frequently collaborated with Hassol. Every tenth of a degree change in temperature affects the extent of climate disruptions. That means the sooner we accelerate efforts, the better, but it doesn’t mean all hope is lost because we haven’t already solved the problem."

    Also by Daisy Simmons..

    For our Australian perspective...

  12. Hurricanes aren't linked to global warming

    Please note: the basic version of this rebuttal was updated on May 19, 2024 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 @

  13. One Planet Only Forever at 05:52 AM on 19 May 2024
    Fact Brief - Does breathing contribute to CO2 buildup in the atmosphere?

    Great brief rebuttal of the ridiculous belief that breathing contributes to increased CO2 levels in the atmosphere.

    A minor nit-pick with a suggested better presentation added in italics:

    The CO2 we breathe is part of a balanced carbon exchange between the air and the earth. In contrast, burning fossil fuels injects oxidized carbon, CO2, into the atmosphere that has been stored underground in hydrocarbon molecules for millions of years, causing a rapid buildup.

    Tragically, the popularity of absurd beliefs requires efforts to 'change the minds' of people who are easily tempted to believe nonsense when the alternative is 'learning about the need to stop trying to benefit from being unjustifiably more harmful'.

    The first Open Access Notable presented in "Skeptical Science New Research for Week #20 2024" - Publicly expressed climate scepticism is greatest in regions with high CO2 emissions, Pearson et al., Climatic Change - highlights that regions benefiting from high harmful CO2 impacts have higher percentages of the population willing to believe nonsense.

    I live in Alberta so I was not surprised by the research results regarding climate skepticism ... and I am painfully aware that nonsense beliefs like 'breathing contributes to the CO2 problem' can be persistently popular among 'highly educated people' who have developed interests that conflict with being less harmful.

  14. The Conspiracy Theory Handbook: Downloads and translations

    On May 17, 2024 the Dutch translation of the Conspiracy Theory Handbook was published, bringing the number of available translations up to 19!

  15. prove we are smart at 14:21 PM on 17 May 2024
    Drought fuels wildfire concerns as Canada braces for another intense summer

    I read of these fires and their terrible impact locally and their downwind smoke impact on its bigger neighbour over the border. Reading more information here, the similarities with some of our Australian Climate Change experiences was apparant, although some of our aussie flora is adapted to fire, probably not so Canadian flora. The catastrophic fires burnt approx a similar area size too -17million hectares and incinerated over a billion animals in the case of the conservative Australian fire estimate                                                  

    Both countries have a terrible colonial history which is still felt in these times- their massive reliance on sinks in the land sector obscures its ongoing support for fossil fuels. Our rating remains "Insufficient."  and Canadian govt? 

    If when "the chickens come home to roost" would apply only to the biggest fossil fuel users and exporters-

    77% of climate scientists agree at least 2.5degrees Celsius is our worlds best effort  It's kinda impressive how many people didn't get the point of the video: she isn't saying that the goals aren't legitimate or necessary, she's pointing out the disconnect between what's potentially necessary and what is actually being done

    We are fiddling while Rome burns or up the creek without a paddle in the case of the biggest flood in my local 150yr history- 2yrs after those horrendous fires-over 2m higher!

    Our societies are comfortably numb, till an outrage from the grass-roots, it's keep us divided and change channels when faced with a major reality check.


  16. Martin Watson at 09:41 AM on 15 May 2024
    There's no correlation between CO2 and temperature

    Bob Loblaw and MA Rodger

    Thank you both for your replies. I will follow up on those suggestions.

  17. 2024 SkS Weekly Climate Change & Global Warming News Roundup #19

    Video -- Skeptical Science - Weekly Climate Change & Global Warming News Roundup #19 4:51    

    Moderator Response:

    [BL] Eddie: when you post a link like this, please remember to give a brief description of what people should expect to find at the other end of link.

    For the information of others, it is a Youtube video reading of the SkS News Roundup of this week (as suggested in the text title of the link).

  18. There's no correlation between CO2 and temperature

    Martin Watson @ 184,

    As you say, the graphic appears in a Science article CenCO2PIP Consortium (2023) 'Toward a Cenozoic history of atmospheric CO2', although more correctly it was in the 'commentary' of the paper and it also then sported a scale for the GMST (which in my eyes isn't so helpful).

    The paper itself does provide a more conventional graphic (Fig2) which does show 20-odd Mya CO2 levels of perhaps 300ppm and GMST of some +3ºC above pre-indusrial.

    While CO2 is the major control knob of Earth's GMST, other factors can make a big difference. The closure of the Panama Isthmus certainly is one of these 'other factors'. The timing is not so well defined (with some even suggesting a date as ancient as 23Mya, this a seriously controversial suggestion), and the changes at work in the climate system which resulted are far from straightforward. The conventional version is that the inital result of the closure was a warmer Earth but that kicked-off the Norhern glaciations which tipped the Earth into a colder phase leading to the recent ice-age cycles (as per for instance Bartoli et al (2005) 'Final closure of Panama and the onset of northern hemisphere glaciation'.)

  19. There's no correlation between CO2 and temperature

    Martin Watson @ 184:

    The diagram you post is not radically different from the graphs and data presented in the intermediate tab of the "CO2 was higher in the past" rebuttal. That rebuttal gives a fairly detailed look at CO2 history over longer periods, and discusses many of the other factors that also affect temperature at geologic time scales.

    From a brief point of view, many other factors would have been different at the time you ask about (25 million years ago), so one would expect that temperatures would not exactly match those of today.

    I suggest that you look over that rebuttal for possible answers, and then continue the discussion on that thread.

  20. Martin Watson at 03:16 AM on 14 May 2024
    There's no correlation between CO2 and temperature

    Could someone clear up another little issue for me. I've come across this graph today, which was taken last year from a big literature review in the journal Science. I'm confused by the dip at about 25 million years ago. It seems to show CO2 levels similar to today but temperatures much higher. I don't think I've seen this dip on other graphs.

  21. One Planet Only Forever at 03:23 AM on 13 May 2024
    2024 SkS Weekly Climate Change & Global Warming News Roundup #19

    Based on the Story of the Week:

    The consensus of people who seriously and responsibly investigate global climate appears to be that, due to the undeniable failure of global leadership by the most harmful powerful people, humanity's future requires adaptation to more dramatically end the use of fossil fuels and other harmful developed human activities plus adaptation to the expensive effort to reduce the excessive accumulated harmful impacts.

    When people resist learning to be less harmful 'liberty reducing law and order' can become the required corrective recourse (far better than the disaster of attempted rebellion against undeserving powerful harmful leaders) ... but that requires people who are focused on being less harmful and more helpful to others to 'govern law and order actions without compromising the actions to get along with people who resist learning to be less harmful'.

  22. The science isn't settled

    Bob Loblaw @108 , 109 : Thanks.

    Bob, you and MAR have a great deal of technical knowledge ~ certainly well above my pay-grade.

    As you both are doubtless suspecting, poster TWFA probably does not have that level of knowledge.  Even so, he wishes to challenge the mainstream science of climate, for his own personal reasons.  (Yet possibly, part of him does wish to learn more.)

    But TWFA has boldly jumped into a gunfight, while he's only carrying a knife.

    ~Or to re-frame the old cliche more humorously :-  TWFA has gone into a gunfight while carrying a rolled-up Forbes magazine.  

    [Future readers can be forgiven for missing my reference to a current May 2024 American politico-legal item of notoriety & humor].

    Still, I welcome TWFA's presence in this thread !

  23. The science isn't settled

    To follow up on MA Rodger's comment (#106) on TWFA's comment (#104) that presents data from Delague and Bard (2010).

    • MAR has provided a link to a free copy of the paper.
    • The journal page is here,
    • That journal page includes a link to Supplementary data, which is a CSV file that includes their TSI reconstruction (discussed, but not graphed or presented in the paper).

    With respect to Delague and Bard's TSI reconstruction, it is worth noting:

    • It provides values on a roughly 10-year interval.
    • The first value is for the year 695.
    • The last value is for 1982.
    • The graph presented by TWFA says "5-per running mean", so it is a smoothed graph where each point represents roughly 50 years.
    • The difference between the maximum and minimum in Delague and Bard's TSI data is 1.2 W/m2. You need to divide by 4 to compare it to the CO2 forcing, to get 0.3 W/m2. You need to then adjust for the earth's albedo, since 30% of TSI is reflected, further reducing the absorbed radiation to 0.21 W/m2.

    We can graph the original data (no smoothing) for the period 1900 to present. It looks like this:

    Delague and Bard TSI


    Question for TWFA:

    How much of the warming observed since 1900 do you think is accounted for by the changes in TSI, as indicated by your source (Delague and Bard)?

  24. The science isn't settled

    I agree with Eclectic that TWFA seems to be getting some rather bad information from dubious sources. Given that TWFA often seems to just jump to a different "talking point" when challenged on his interpretation or argument, it seems that he lacks understanding of exactly what point his snippets of information are supposed to represent.

    As an example, after arguing about the features of the Jevrejeva sea level reconstruction, in comment 99 I pointed to a RealClimate post that shows the Jevrajeva methodology is suspect. In comment 100, TWFA did not make any attempt to justify the use of Jevrajeva - instead, he made a bogus general argument about trends and processing, and did a "Look! Squirrel!" about comparing 1600 with 1750. After I commented in #101, he continued with more Just Asking Questions.

    I will attempt to respond to TWFA's comment 102 in two ways. First, to address his general question about past climates, what we know, and what does it tell us.

    • The information we have about past climates is limited, and often requires use of proxies (geological records, tree rings, ice cores, etc.) That does not mean we "know nothing". though. In essence, the proxies are the result of past climates, rather than direct measurements of the temperature, precipitation, etc.
    • By understanding the physics of climate (including physics of solar output, etc.), we can use the evidence we do have about past climates to determine what factors were playing a role at that time. And we can compare that to what we can directly measure about those factors now.
    • ...and we see that the best explanation for current trends must include greenhouse gas changes (mostly CO2 from fossil fuel use) to get things anywhere close to right. Other factors were active in the past to a sufficient degree to cause changes we see in the past - but they are not sufficient now to cause the changes we are seeing now.
    • To directly respond to TWFA's "I don't understand how what is now deemed to be abnormal can be so determined if prior normal cannot be",
      • We can determine what "prior normal" was - at least to some limited extent. But that limited extent contains a range of uncertainty due to our limited information. (Even today, we have limits on what is measured.)
      • When we interpret our evidence of the past, we have to include that uncertainty range. Hence Eclectic's question in comment 98: the broad mauve band versus the smooth calculated curve in the graphs that were being discussed.

    The second approach I'll take is by analogy. A thought experiment.

    • Let's assume I am on trial for stealing money from TWFA's bank account.
    • The prosecution has shown evidence of an electronic transfer of $10k from his account to mine on a particular date last month, and evidence that this transfer was initiated for a login from my IP address. At the time, TWFA was on vacation in central Africa, with no internet access.
    • I have presented evidence that TWFA's bank account balance in the past has gone up and down by thousands of dollars from month to month. I do not have information about individual transfers in the past, but I do have evidence of TWFA's approximate income and typical monthly expenses.
      • I argue that this past range of bank balances raises doubt that I stole the money. How can we be sure that some expense that existed in the past did not cause the removal of $10k?
      • On cross, the prosecution presents detailed records that show each transaction for the past year (when detailed records are available). None of the historical  expenses that cause $10k changes in the older historical bank balances were happening during the period I am accused of stealing money. They again point out that the current detailed records include a transfer to my account.
    • The judge ends up saying "it's settled - guilty as charged".

    Climate scientists have spent a lot of time looking at past climates, using the available (albeit limited) evidence. We've spent time to understand the physics, analyze the data, and determine the range of effects that have caused past climate changes. And now we've looked in detail at the role of CO2, and we are observing the effects of increased CO2 that are in broad agreement with theory.

    There are things we still want to learn (always), but the fact that CO2 is a greenhouse gas, has caused most (if not all) the warming in the recent past, and will continue to cause warming in the future is settled science.

  25. The science isn't settled

    MA Rodger @106 :  Thanks for that.

    TWFA hasn't yet said where he gets his background info from ~ but it seems he had been lurking in some mighty crappy corners of the internet.   Corners where the order of the day is to supply doctored graphs and other deceptive half-truths to the Man-in-the-Street.   And in corners where the products marketed are heavily slanted toward conspiracy, outrage, and FUD.

    Still ~ as Pollyanna would say ~ he may be on the path to thinking things through, and picking up better-quality information.

  26. The science isn't settled

    TWFA @104,

    I assume your presentation of somebody's helpful re-drawing of Delague & Bard (2010) fig 5 (below) is your true message and your comment is being ironic.Delaygue&Bard(2010)FIG5

    There are some seriously dodgy proxy TSI reconstructions that survive zombie-like through the decades. 

    Bard et al (2000) has been criticised for finding larger wobbles in TSI than other studies using the same proxy data (eg Vieira et al (2011) [fig5 below] or Wu et al 2018) but I don't see that criticism is greatly extending to the Delaygue & Bard (2010) graph you post.

    Given there is no dispute with the measured TSI record over the last half-century (so after your graphic runs out) during which we have also seen rising global temperatures, would an increase in +1.5Wm*-2 in TSI 1650-1950, that equal to a spherical forcing of +0.375Wm^-2 so less than a decade's-worth of the GHG forcings seen of late; would such a TSI forcing applied over half a millenia be particularly significant?Vieira et al 2011 fig5

  27. The science isn't settled

    TWFA @104 :

    (Thanks ~ good timing ~ I was about to leave the house.)

    Your question would be better expressed, not as "nature bringing temperature up stopped [in 1850]" . . . but rather as : nature reducing the greater downward pressure (by about 1850).  Of course, from a Milankovitch-cycle aspect, we would expect the slow gradual line of temperature decline . . . to continue for about 15,000 years, until "the ice really hits the fan" . . . ;-) . . . and the world plunges deep into the next Glacial Age (a genuine Ice Age).

    [ So there was no rush for humans to burn all their coal to keep the next glaciation at bay. ]

    TWFA, the forcing from the sun ~ is only one factor in the big picture.  And as best I currently understand it, the Little Ice Age was caused by two roughly equal factors.  Those factors being (A) the Grand Solar Minima [Spoerer, Maunder, etc] . . . and [B] a period of greater frequency of major volcanic eruptions [stratospheric particulates causing cooling ].   A Grand Solar Minimum, by itself, is rather weak in its cooling effect.

    The major factors causing climate change are : Albedo, Sun, Particulates, and CO2  (currently!)

    Yeah, it's complicated.  But the scientists have been doing good work in getting an understanding of it.

    Fair to say : the science is settled enough for our current practical purposes.   It is the politics of how to tackle our self-made problem . . . which is the difficult part to carry out efficiently.

  28. The science isn't settled

    OK, so in 1850 whatever forcing nature was doing to bring temperatures up stopped and we took over, the sun had nothing to do with anything, right? 

  29. The science isn't settled

    TWFA @102 :

    Best if you look at the bigger picture ~ not just the past 500 years.

    As you know, back before about 150-200 years, the various temperatures must be assessed by means of proxies.  And the more proxies over a wider area, then the smaller the amount of uncertainty.

    The proxy evidence points to the past temperature normals [note: plural] following a cycle [Milankovitch] during the past million years.  For instance, during the Holocene period, world temperatures were at a high plateau for roughly 5,000 years . . . followed by a slow decline of [all rough figures of course] about 0.7 degreesC for the past 4.000 years.    ~All this, due to natural factors.

    During that slow decline, there were small deviations from the line of decline [owing to certain transient natural causes].   E.g. the Medieval Warm Period of several centuries showed a world warming of about 0.3 degreesC ;  and the Little Ice Age (including the 1600-1800 period you express interest in) showed a downward "blip" of about 0.3 C  . . . and thus was about 0.6 C below the peak of the MWP.

    The LIA finished roughly 1850 ~ by which time world temperatures had reached the "normal"  i.e. were near the average line of decline from the Holocene peak.  And by 1850, thermometer readings were starting to be used (outside the Central England Temperature region).   And so we know, quite accurately, that the world temperatures have then "shot up like a rocket" ~ way above the (Milankovitch-related) line of natural decline . . . and world temperatures today are roughly 0.5 C above the peak of the Holocene.

    # A very impressive sudden warming change (and with more to come) ~ and all this is clearly "not natural" in its causation.

    TWFA ~ so where is your "not unreasonable" objection?

  30. The science isn't settled

    So the answer is, "What was going on prior to 1850 is not important", or all that data is suspect, or has not been presented properly, or some such thing?

    I don't understand how what is now deemed to be abnormal can be so determined if prior normal cannot be. Again, the simple question is, what was the temperature doing in 1600, 1650, 1700, 1750 and 1800, as best can be estimated? It's not an unreasonable or silly thing to ask.

  31. The science isn't settled

    TWFA @ 100:

    I see where your problem is. You have no idea what you are talking about.

    Determining trends is "processing". The data that goes into that trend determination will affect the trends that are calculated. Noise does matter, and uncertainty in trend calculation takes that into account.

    Of course, you are probably determining "trend" using the eyecrometer, so it is easy for you to just see what  you want to see, and filter out anything you don't like.

    ...and this may be news to you, but "global sea level" is not something that is measured using a single data value. It requires a bunch of values at different locations, and  you need to combine those data values together properly to get an estimate of a global value. You know: that "processing" step?

    ...and because sea level measurements are not evenly distributed, you can't just average the individual locations with equal weighting. The weighting method (more "processing") does matter, and that is what Jevrejeva does poorly.

    As for your focus on the 1700s - there are many factors that affect sea level, both locally and globally. If one factor affects sea level in 1700, that does not mean that other factors can't affect sea level at another time. I think you need to read the "Climate's change before" rebuttal. There is a reason it is #1 in the "Most Used Climate Myths" list.

  32. The science isn't settled

    Noise or improved processing does not change a trend fom negative to positive, where were the sea levels in 1600 vs 1750, higher or lower? Is the assertion that but for mankind the sea levels today would be at or below the level they were in 1600?

  33. Medieval Warm Period was warmer

    Please note: the basic version of this rebuttal was updated on May 9, 2024 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 @

  34. The science isn't settled

    It probably comes as no surprise that TWFA is relying on the Jevrejeva sea level reconstruction. It is probably the least reliable one, and a 2013 post at RealClimate discussing the state of knowledge of sea level rise has provided detailed discussion of the methodology and its problems.

    Two paragraphs from that RealClimate post:

    The one curve that does not show an unprecedented recent rate in Gregory et al. is the data of Jevrejeva et al. (2008). That contrasts with our treatment of the same data in Rahmstorf et al. 2011 (Fig. 5), where we applied a stronger and more sophisticated smoothing (as compared to the running average used by Gregory et al) which lowers the temporary high peak in the rate around 1950. This peak is not found in any of the other data sets, and as shown in Fig. 2 above, it makes the Jevrejeva data run outside the grey range found by combining all contributions.

    I think this peak is spurious and results from the fact that the data of Jevrejeva et al. cannot be considered an estimate of global-mean sea level on such relatively short time scales (a couple of decades). For example, in this data set the North Atlantic data (including Arctic and Mediterranean, overall 16.6% of the global ocean area) provide 31% of the global average and are weighted four times as strongly as the Indian Ocean, although the latter is larger (19.5% of the global ocean). The Northern Hemisphere is weighted more strongly than the Southern Hemisphere, although the latter has a greater ocean surface area. (For more on the Jevrejeva weighting scheme, see our reader’s exercise below.) That is not to say that other tide-gauge based estimates guarantee a properly area-weighted global sea-level history, but it means that Jevrejeva et al. are guaranteed to not represent an area-weighted global mean, while e.g. Church and White (2006, 2011) are making a decent attempt at representing a global mean.

    Follow down that RealClimate post to the section titled "A reader’s exercise: the “virtual station method” of Jevrejeva et al" for further details.

    Perhaps TWFA will illuminate us on why he prefers that Jevrejeva analysis, but I won't hold my breath.

  35. The science isn't settled

    TWFA @90  (and others) :

    Yes, the two graphs are somewhat different ~ and they both contradict your claims.  (How do you disbelieve your own eyes?)

    Your Jevrejeva Figure 1 shows not only a great deal of jagged variation in the main black line (which is quite to be expected in averaged measurements at different dates) . . . but also shows the broad mauve bands above & below the averaged measurements in the pre-1850 region.

    TWFA, what do you suppose that very broad mauve band means?  ~ For one thing, it means that the smooth calculated curve is merely a convenient approximate fit.  Also, that the smooth curve is not imposed by Divine Will upon that wiggly graph in order to show TWFA a 5mm sea level fall (& rise) between 1700 and 1800.

    TWFA, in this thread please do not raise all that Conspiracy Theory stuff ~ it is difficult to have an intelligent discussion about real things, if you choose instead to wander off into Conspiracy Crazy Land.

    The phase out of Fossil Fuels is not (and cannot) be carried out "overnight".   It is looking like it will take maybe 40 years or more ~ and so your precious plastic shopping bags will be available for quite some time yet.  No need for alarm or panic.

  36. The science isn't settled

    Correction, vegetable soup into corn chowder...

  37. The science isn't settled

    scaddenp, FF phase-out means petrochemical phase-out as well, you can't have one without the other, refine a quart of corn chowder into a quart of vegetable soup with nothing left over, so as long as there is plastic, insulation for all those wires needed in the FF-free world and asphalt to roll the synthetic rubber Tesla tires on, there will still be at least a third of every barrel of crude being cracked into some form of hydrocarbon fuel or gaseous byproduct that cannot be sequestered or stored, only burned.

  38. The science isn't settled

    I don't know that innovation, adaption and migration will be cheaper, but I know it has worked every time tried. On the other hand you do not know the global thermostat approach will work for sure, will be cheaper, or even that, given all the people on the planet that may not be able to be controlled without global autocracy, a fate worse than a few degrees and inches of water, IMO, it can or will work even if the West goes net negative or transfers wealth to the underdeveloped world to bring us down to equilibrium for our sins.

  39. The science isn't settled

    Sorry, you're wrong again, perhaps your eyes didn't notice the first chart starts at 1700 and the second at 1800.

    In the second chart the authors used data from the 2014 study, which basically took some of the noise out of the '08 paper but did not change the overall curve from 1700, however this particular evangelist cut off the data prior to 1810 to show the slight dip between 1810 and 1860 in order to make an apparent human caused reversal to fit the Industrial Revolution chronological orthodoxy, even though the lagging emissions curve still needed quite a bit of explaining... perhaps in the future they will discover or "adjust" preceding emissions to better fit the narrative.

    By the way, I am not "regurgitating" anything, I first noticed the second chart about six months ago when somebody posted it as some sort of devastating proof of the coming inundation we are to be blamed for, it didn't make sense to me based upon the lagging emissions curve, then I drilled deeper into the source data and it all made even less sense.

    In any event whether the science is settled (an oxymoron if there ever was one, no theory or law following the scientific method can ever be proved right, only not yet proved wrong) or not is moot, the evangelists ARE getting their way and we WILL be spending hundreds of trillions over the next four or five decades, probably forgoing a chunk of liberty along the way as well, seeing if we can operate a global CO2 controlled thermostat, either it will work, or nature will have something to say about it.

    My money, if there is any to be left over, is on the buckets.

  40. The science isn't settled

    Still not answering:
    "Again, why do you believe adaption is going to be cheaper than FF phase-out?"

    This is the core of the issue isnt it?

  41. The science isn't settled

    TWFA @90 (etcetera) :-

    Your second graph clearly does not support your claim in @88 that:  "...sea levels began to rise in 1750, when James Watt was twelve years old..."    Indeed that graph shows sea level falling until about 1860  (when James Watt had been dead forty years).

    And your first graph ( Jevrejeva; Figure 1 ) shows no support for your wild claim, whatsoever.  Please consult your optometrist, urgently.

    TWFA, it appears you are regurgitating some wild claims from some third-party source.  Where is that source ~ and how did they get it all so very wrong?

  42. The science isn't settled

    Oh, and as to their conclusion, inertia works both ways, if temperature is the controlling factor, in order for the levels to stop receding and "turn the tide" around 1750 the temperatures would actually have to have been climbing beforehand.

  43. The science isn't settled

    Of course I looked at Fig. 1... the ebb point in curve is at 1750, clearly rising by 1800 and well on the way by 1850.

    I just want to know why, if we are the ones causing all this, that it began long before we were emitting measurable amounts of CO2, which was around 1890. Do I need to show you a chart of sea levels vs emissions?
    Time series of sea level anomalies (blue) Jevrejeva et al. (2014).
    Time series of sea level anomalies (blue) Jevrejeva et al. (2014).
    Million tons of carbon emitted from burning fossil fuels from the Carbon Dioxide Information Analysis Center (CDIAC 2014)

  44. The science isn't settled

    TWFA @88 ,

    The paper Jevrejeva et al., 2008  does not support your wild claims.

    Did you actually read that paper?  It appears you did not look at Figure 1, and it appears you did not look at Figure 3.

    Nor does it appear that you read or understood the Conclusion of Jevrejeva  ~ which states in its final sentence :-  "However, oceanic thermal inertia and rising Greenland melt rates imply that even if projected temperatures rise more slowly than the IPCC scenarios suggest, sea level will very likely rise faster than the IPCC projections [Meehl et al., 2007]"

    TWFA ~ where do you get your strange ideas from?

  45. The science isn't settled

    Come on, 2 buckets a day is 730 a year, and now you're bitching that it's a thousand a year instead, like that changes anything, it's all within an order of magnitude of my first 365 estimate, why didn't you just go right to 100,000 a century for greater effect?

    The point is we KNOW such methods work and have been effective, not just on the coast, but improved insulation, hydroponics and gee, maybe agriculture will come back in thenorthern climes.

    The Venetians have been dealing with rising water since the 5th century, on the other hand we only have an alleged 97% certainty that by adjusting the atmospheric content of CO2 up or down by a fiftieth of a percent from the four tenths of a percent it is now that we can control the temperature of the entire planet and avoid having to buldoze all that sand.

    Besides, according to the Jevregeva data in '08 and refined in '14 the sea levels stopped receding and began to rise in 1750, when James Watt was twelve years old and over a century before our emissions were even measurable, see Fig. 1
    Jevrejeva '08

  46. The science isn't settled

    TWFA @85 ,

    the Obamas' expensive mansions have something like 10 feet (or more) of elevation . . . and judging by expected sea-level rise, the Obama grandchildren may well need to sell (or abandon) the mansions when they themselves  reach the age of 100 years or thereabouts.  Yes, it's a sad problem when super-rich families have to move house ;-)     And perhaps you could spare some thoughts & concerns for the poorer folks who live on the coastlines of the world?

    TWFA . . . please use more mathematics, and less sour grapes.

  47. The science isn't settled

    It is not 2 buckets - it is close to 1000 buckets a year. Maths matters.

    "Nobody with beachfront property of any size is going to be moving"

    Trivial to see that is not true. Why do you believe that given that coastal erosion data and property loss is readily available? You can also look up loss of agricultural land to salt incursion.

    Again, why do you believe adaption is going to be cheaper than FF phase-out?

  48. The science isn't settled

    I came up with that bucket in a quick mental estimate, which was well within an order of magnitude of your exhaustive analysis... so big deal, it's two buckets a day, not ten or a hundred, and that's for somebody with the money to have an acre on the beach.

    Nobody with beachfront property of any size is going to be moving, I can assure you, even after hurricanes with 15' storm surges they don't. Obama has two lavish oceanfront estates in the Atlantic and Pacific, he doesn't seem to be worried about his great, great grandkids drowning.

  49. The science isn't settled

    "a five gallon bucket of sand tossed upon your acre of oceanfront property every day will keep up with 8" of sea level rise over the next century."

    I think that example is problematic.

    8" = 200mm -> 2mm per year. Global sealevel rate is currently 3.4mm and accelerating.

    Check your maths on the 5gal of sand. I make that 19L or 19,000 cubic cms. 1 acre = 40470000 cm2  19,000/40470000 isnt remotely keeping up with 2mm/year of sealevel. Out of curiousity, where did you find this statement about the 5gal bucket? Sounds like a source bent on misinformation.

    Where do you get your sand? At a sustained 4mm/year of sealevel rise, your beachs vanish.

    Sand or any other easily mined material is also highly erodable - without an expensive seawall, wave action will take it away.

    And finally, the real point. Adaption is not free. It costs to make those changes. Why are you so confident that adaption is cheaper than just converting energy sources to renewables, especially as renewables+storage has better LCOE than FF?

  50. The science isn't settled

    I still get hung up on the plane example, not sure anybody is framing it correctly.
    If you consider the plane to be built upon an aeronautical theory of AGW and is predicted with 97% certainty by those who designed it to be airworthy and get you to your destination, which would be surviving changes in the climate by preventing them altogether using a human controlled CO2 thermostat to control the temperature of the verses planet... verses choosing an alternative, far more pedestrian and proved means of transportation to climate survival that has worked for thousands of years, namely innovation, adaption and migration, which would you choose?

    For example, a five gallon bucket of sand tossed upon your acre of oceanfront property every day will keep up with 8" of sea level rise over the next century.

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