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Comments 1 to 50:

  1. New paper shows that renewables can supply 100% of all energy (not just electricity)

    scaddenp et al.

    Arriving at this discussion somewhat belatedly, it seems appropriate to point out at this juncture that Ricardo said recently they have designed a low cost, rare earth free EV motor:

  2. The 1C Milestone

    I would put it this way: "Safe" ≠ "benign."

    Yes, indeed, Rob. It also appears to be true that 2C is not necessarily safe; there is no science which says it is. Kevin Anderson has said this and James Hansen has said this.

    We may already be in unsafe territory at 1C (maybe 2C) with more already built in and, as ranyl pointed out, aerosols are masking some of the rise, so any decrease in burning fossil fuels (or maybe even a slowing of the increas), though necessary long term, could make matters worse over the medium term. To my mind, we're already in the non-benign range.

  3. How to make sense of 'alarming' sea level forecasts

    SLR (sea level rise) estimates can only rise. A ratchering process in estimates is due to the trained conservatism of scientists, and the political make up of the IPCC pannel. As such, we must develop technologies to control SLR. We need to expand our sense of what is possible because we will have not choice SLR and agricultural inhospitability are programed into the world unfolding. To deny the possiblity of creating solutions is unwise.

  4. How to make sense of 'alarming' sea level forecasts
    Charlie, the source is hyperlinked, from the URL the linked version is a "COP19" paper rather than the actual AR5 report.The AR5 text does gives the 1993 - 2010 numbers, and "1.7 [1.5 to 1.9] mm yr between 1901 and 2010" (which is very similar to the 1901 - 1990 figures above).
  5. One Planet Only Forever at 13:57 PM on 30 August 2015
    Tracking the 2C Limit - July 2015

    Bozza @ 22 and 23,

    My reference to mountain climbing was an attempt to avoid the confrontational response often generated when I say that the real problem is the business operators, investors and consumers who prefer the perception of prosperity they have when they can get away with obtaining what they want quicker or cheaper (the quickest and cheapest way to do or get things is usually the least acceptable way it can be gotten away with, involving higher risk of damaging consequences to others).

    The real problem is the way the free actions of people in the free market encourages businesses and consumers not to care about how unacceptable their personal pursuits of perceptions of prosperity are. It even leads them to consider any point made about the unacceptability of their perceived or desired prosperity to be a personal threat.

    So, as I see it, the real problem is the way that socio-political-economic systems that determine acceptability of an activity based primarily on popularity and profitability encourage the development of activity that all others cannot be allowed to benefit from (people compete to benefit the most from those limited opportunities). It also encourages the development of activity that creates consequences for others with investors and consumers doing anything they can get away with to avoid personally suffering the full deserved consequences of their risk taking pursuits of pleasure and prosperity. Those who get away with being the least acceptable win the most.

    The unacceptability of already fortunate people getting even more benefit from burning fossil fuels is not the only developing better understanding that challenges the perceived prosperity of many of the wealthiest and most powerful. But of all the developing better understandings of the unacceptability of 'developed human enterprise' the climate change challenge clearly affects the largest amout of illigitimately developed perceptions of prosperity. And it generates the expected perception of threat and expected response to a threat by those who feel threatened by it.

    That undersanding is the best explanation I have for the popularity of the lack of action to date to avoid the creation of more significant problems for future generations. It is why the achievable 1.5C limit (easily achieved if the wealthiest seriously tried to do what should have been started 25 years ago), was never seriously attempted to be achieved. And it is why 2C and 3C and 4C and 5C would also not seriously be attempted to be achieved.

    Collectively, the success of unacceptable pursuits of what people want is, and always has been, the most serious challenge facing humanity. And this climate change challenge has increased awareness of how deliberately unacceptable many of the wealthiest and most powerful actually are.


  6. Tracking the 2C Limit - July 2015

    Rob @29

    Yes, that's much better: keep as close to 2 degrees as possible (even when we exceed it).

    As for a definite zero-point for the temperature anomaly, this is something I've wanted for a long time.  I love it.  I just wish that henceforth the IPCC standardize on it too.

  7. How to make sense of 'alarming' sea level forecasts

    What is the source of Figure 13.3e shown in this article?   

    The figure in WG1AR5 doesn't have the 1901-1990 and 1993-2010 boxes or show the rates for those periods.   The AR 5 figure is at

    It shows tide gauge records, which don't show the 3.2mm/yr recent rise ....  that only shows in the satellite record, not the tide gauge record.

    Please show a 3.2mm trend line from 1993 to 2010.

    One can easily look at the chart and see that there is not a doubling or rate in the data presented.   (I believe the data is Church and White 2011 and Jevrejeva et al. (2008).  The purple and blue appear to be paleo/salt marsh data.

    Moderator Response:

    [DB] "What is the source of Figure 13.3e shown in this article"

    It was linked for you in the article, as noted by others.  However, it was moved.  An archived link is here.

    "Please show a 3.2mm trend line from 1993 to 2010"

    From AVISO:

    And from UCAR:

  8. Tracking the 2C Limit - July 2015

    Tom... I'm hoping, if I just keep posting this month-after-month, eventually more authoritative researchers and institutions will establish an agreed upon measure of preindustrial temperature. Who knows, they may never even notice this but it's certainly worth a try.

    As you say, this is probably good enough for where we are now. I think you're also right that it's worth noting that the 1880-1909 baseline may not account for some additional preindustrial warming. I'll include that for the next update.

  9. Tracking the 2C Limit - July 2015

    TonyW @28, Rob Honeycutt @29, the article by David Spratt uses Mann et al 2008 (cited as Mann, Zhang et al*), although he does not specify whether or not he used the CPS or EIV reconstruction.  He also used a 1750-1779 baseline unlike the 1736 - 1765 baseline I used @11.  Further, it is not clear whether or not the Mann 2008 data was renormalized for the NOAA dataset.  For a more direct comparison, I get a 0.135 C temperature increase from the 1750-1779 baseline relative to GISSTEMP, and 0.148 C if normalized using the EIV reconstruction.

    Curiously, in his article Spratt links to a chart indicating research on paleotemperatures which does not contain Mann et al 2008 (and indeed, which contains primarilly NH temperature reconstructions, and in at least one case a NH extra-tropical temperature reconstruction):

    For comparison, here is the Mann 2008 global EIV reconstruction:

    The key point from this is that the uncertainties in paleoreconstructions are such that preindustrial temperatures could be greater than the 1880-1909 average (by as much as 0.1 C), but are far likely to be less than that average.  Indeed, they could be 0.4 C below that level.  Given this, there is nothing wrong with just using the 1880-1909 average a a preindustrial estimate.  It is worthwhile noting, however, that that baseline is likely to give a low estimate of the temperature increase since the preindustrial.

    (*  In the citation of Mann et al, 2008, Spratt mistyped the page number as 14252, whereas it is actually 13252)

  10. Tracking the 2C Limit - July 2015

    Digby @27... Psychologically speaking, I think it's probably important to keep referencing 2C even when we go over that line, rather than start thinking about avoiding an even higher number. Rather than talk about 4C, talk about how close we can keep temps to 2C, else 4C will become a self-fulfilling prophecy. 

    TonyW @28... I've seen Mann make this argument before, and I'm sure he's correct. It's just hard for me to (currently) justify making that adjustment to the baseline without specific data to base it on. I had thought about this when creating the graph, but decided to stick with a 30 year baseline that's as close to pre-industrial as I could get with the available GISS data.

  11. Ivar Giaever - Nobel Winning Physicist and Climate Pseudoscientist

    Giaever has made a new address to the Lindau Nobel Laureate 2015 meeting.

    Here is a link to the video:

    Giaever on Climate Change

    Here is a link to my rebuttal of his speech:

    Rebuttal of Giaever Speech

    His speech is full of poorly researched data which does not represent what he says it does.

  12. Tracking the 2C Limit - July 2015

    Regarding the 2C limit, James Hansen had this to say in one of his recent missives, "Why have policymakers turned away from GHG amount to temperature as the metric with a value (2°C) seemingly pulled from a hat? Could it be because 2°C allows politicians to set emission targets to be achieved in the future when they will be out of office?"

    Regarding baseline, what do you make of this article (look for "it's hotter than you think") that claims surface temperature in 1750 was 0.2C less than the 1880 baseline? If it's right, we're already at 1.2C above pre-industrial.

  13. Here’s what happens when you try to replicate climate contrarian papers

    Tom Curtis @13

    I am well aware of the works and the scientific approach of Roger Bacon and also that Aristotle was not just some simple philosopher who didn't study any science using empirical evidence. I am also aware that Greek philosophers like Erastothenes did make observations and used them in empirical ways, like for instance, estimating the circumference of the Earth. Yes, my statements were simplistic, but that was because I did not want give a full account of the development of modern empirical science. As for Newton, I am also aware that he spent more time on religious works and alchemy than he did on the scientific and mathematical studies that caused the revolution in the science that now underpins the modern world. The development of modern science is not a black and white affair where suddenly alchemists become chemists, or astrologers become astronomers. My main point is that at the cusp of the 17th century the study of science was done mostly by deeply religious men and was more used to verifying what was in the Bible, than about what the real world was actually like. It is true that if it weren't for the observations of Brahe, Kepler would not have been able to refine the Copernican theory. In fact, Brahe was so much a believer in the Ptolemic view of the motion of the planets because of his religious beliefs and his faith in the teachings of Aristotle, that he developed his own geocentric theory to account for the anomalies of planetary motion rather than simply accepting the Copernican view. As for Kepler, he spent most of his life trying to fit the planets into a geocentric model where the orbits fitted the platonic solids. He abandon his ideas because the actual observations, Tycho Brahe's observations, of the real world did not fit his theory. It was only then that he introduced ellitical orbits into the Copernican model. This was truly a new way of thinking for the time, as he had to abandon deeply held beliefs that he had gained through his religious faith. The vast majority of scientists of this time were highly religious and their scientific efforts were to enhance religious belief and glorify the church. This period is truly unique in that at the beginning of the 17th century, science was done mostly by religious men and used more to verify the prevailing religious orthodoxy. By the end of the 17th century, science was more focussed on the real world and what was actually being observed, i.e. done for its own sake. The Galileo story is just a part of that narrative, and yes he did have contray views to what was generally accepted at the time. However, most of what was accepted was because it verified the religious teachings of the church. Galileo's assertions were not based on religious orthodoxy, although it was obvious from his treatment that there were some religious figures who were sympathetic to his views.

  14. Tracking the 2C Limit - July 2015

    One Planet @ 21

    I think a misunderstanding has been committed!  I meant that it is probably impossible to make an accurate portrayal on the graph of the amount of lag in the system, given that it might be anything from 0.3 to over 1.0 degrees.

    Of course humanity needs to make every effort to avoid dangerous climate change.  If we can't avoid 2 degrees, we should at least be trying our utmost to avoid 4 degrees of warming.

  15. Here’s what happens when you try to replicate climate contrarian papers

    mancan18 @12, your account of the advance of science is too simplistic.  It neglects the strong emperical vein in Aristotle's philospophy, which he put into practise especially as regards biology.  It also neglects the development of that empericism by Roger Bacon (considered by some the inventor of modern science).  It also neglects that the early scientific revolution developed out of medieval scientific enquiries, best illustrated by the fact that Newton's research in fact mirrored that of Roger Bacon.

    Worse, you demonstrate an oversimplistic idea of empericism in science.  It was the geocentrist Tycho Brahe that was the great observational astronomer, not Copernicus.  And his 'refutation' of Copernicism stood at least in part on emperical grounds, notably the absence of stellar paralax (predicted by Copernicus), and initially by a wrong relation with regard to the parallax of Mars.  While Copernicus's theory was in some ways emperically superior, was "intrinsically no more accurate than Ptolomy's", and commonly predicted "errors of a day" in the timing of lunar eclipses, not to mention the wrong length of year. (Kuhn, The Copernican Revolution p 288)

    Likewise Galileo's theories faced emperical falsification from the start, predicting only one tide per day (for instance).

    The fact is the transition from scholasticism to science was a messy affair.  We cannot deprive Galileo's contemporarys of the mantle of scientist just because they were geocentrists, or employed some scholastic arguments unless we wish also to exclude Copernicus (who argued for his theory based on the "perfection" of the circle") and Newton (who was also an alchemist).

  16. Here’s what happens when you try to replicate climate contrarian papers

    M Tucker at @5 and Ger@6

    I think you will find that at the turn of 16th and 17th century when Galileo lived, that there was little scientific evidence for any theory. Science at that time was more philosophical, based on the thinking of Aristotle. This way of thinking came from the Greeks who preferred  to philosophise. They used to just sit around and think about things rather than make actual observations and do experiments to collect data that supported their theories. The prevailing scientific method at the cusp of the 16th and 17th century was to only propose theories that reinforced the Bible. The vast majority of the "scientists" at the time studied in monasteries or were alchemists trying to convert lead into gold. Copernicus was a monk and proposed his heliocentric theory as an alternative to the Ptolemic biblical geocentric theory only as an interesting thought exercise which he saw as a much simpler explanation. He supported his heliocentric ideas with geometry but was too afraid to publish until he was on his death bed. It is no coincident that the spread of the Copernican theory to scientists like Galileo was only possible due to the recent invention of printing. This allowed ideas and findings to be spread more widely. Galileo at least made observations and collected evidence. His work on falling bodies was certainly unique since the prevailing Aristolitean scientific view at the time was that heavier objects fell faster that lighter objects. And we already know that through his observations of Jupiter and the Moon through his recently developed telescope, he gathered evidence of the correctness of the Copernican theory. This correctness was further refined by Kepler, also a deeply religious man, through proposing that the planets moved in elliptical orbits, a position that took him 20 years to come to using the highly accurate data collected by Tycho Brahe, who incidently still believed in a biblical geocentric theory. The whole issue, heliocentric versus geocentric, was finally put beyond all doubt later in the 17th century by Newton, incidentally another deeply religious man, with his Theory of Gravity and the invention of Calculus using the co-ordinate geometry that had recently been proposed by Descarte. Galileo was one of the first scientists who used a modern scientific approach (hypothesise, propose a theory, create experiments, observe, collect data, and test) to justify his ideas. This is quite unlike the many so called "scientists" at the time who were more philosophers who conducted few expirements, collected little supporting data and preferred to use the bible as evidence to justify for their ideas. Galileo was a modern scientific thinker unlike most of his contemporaries. The Galilean story just shows that all scientific ideas are the meticulous work of many scientists pursuing a common truth.

    Theories, where the observations and evidence are contry, are thrown out. Theories, where observations and evidence are supporting, are further refined and become increasingly accepted as scientific truth until there is only one scientifically indisputable piece of evidence that can falsify the theory. In climate science, the contrarians have not found a single piece of evidence that disproves the fundamental scientific idea that rising greenhouse gases will warm the planet. Also, they have not proposed a single coherent alternative scientific idea, nor provided a single piece of indisputable evidence that explains why the current warming is happening. All they have provided are some interesting distracting talking points, which, so far, have only served to further reinforce the idea that AGW and CC is actually happening.

    Just asking. What are the views of the primary scientists who actually collect the data from the primary sources (i.e those on the ice flows gathering the ice core data, those collecting the glacial retreat data, those gathering the sediment data, those collecting the carbon dioxide data, those actually creating and verifying the climate models etc.)? Are there any contrarians amongst the primary scientists who actually collect the data, or are the contrarians only found amongst the secondary scientists who use the data collected by others, in an effort to debunk the basic AGW and CC proposition?

  17. One Planet Only Forever at 07:09 AM on 29 August 2015
    Tracking the 2C Limit - July 2015

    bozzza @ 22 and 23,

    We are probably thinking similar thoughts.

    My point remains that it is not appropriate to declare 2C unachievable making the task impossible, therefore not to be attempted to be met.

    The wise mountain climber will turn back rather than take the risk of attempting to summit a mountain when conditions are not favourable. The risk taker pursuing glory is more likely to die, never to reach the summit, or any others. That wise one gets to try again.

    Unlike that experience, this pursuit of change to the way that humanity determines what is acceptable and permitted cannot take a break just because the current socio-political-economic conditions appear unfavourable.

    Also, unlike a risk taking mountain climber who is the one to suffer the consequences of their thrill seeking irresponsible risk taking, the irresponsible pursuers of benefit for themselves from the burning of fossil fuels (chasing after undeserved perseptions of prosperity), create consequences faced by others.

    That understanding of the unacceptability of risky, damaging and ultimately unsustainable pursuits by people who will not likely suffer the consequences of their grabs for personal benefit any way they can get away with needs to become common understanding ... forevermore.

  18. You can’t rush the oceans (why CO2 emission rates matter)

    Another great SKS article.

    I remember when reading James Hansen's "'Storms of My Grandchildren" that he said at some point the oceans would slow down their uptake of CO2. I also remember being a bit surprised that he didn't seem to know when or at what rate this slowdown would happen. Is this because the 6 points of the domino effect of ocean chemistry and climate are too complicated to model or otherwise work out?

  19. Tracking the 2C Limit - July 2015

    This is a great idea. Maybe the graph could become a box on the right hand side of the home page, and if you click on it you go to the latest monthly update.

    I reckon there's room on the graph for a pointer to the bottom of the CO2 graph giving the level there, a pointer giving the level at about 1940 and one at the end of the graph giving the current/latest value.

    Maybe regarding the already committed 0.3 C (or 0.5 C - notice the space before the C) have an arrow along the 30 year trend line with a pointer saying 'Already committed"? I'm not sure about this last one.

  20. Tracking the 2C Limit - July 2015

    It is interesting that politicians and the media here in Australia talk in terms of the 2 deg C as being a limit as though it is possible to keep the warming below that limit if emissions are reduced drastcally globally. This view leads to misunderstanding in two regards. Firstly, there is already copious evidence that irreversible climate disruption and ocean warming and acidification is under way. Secondly, so long as there are greenhouse gas emissions the degree of atmospheric warming will increase even though some of the emissions will continue to be absorbed in the oceans.

  21. Tracking the 2C Limit - July 2015

    .. if a mountain climber were to be subject to groupthink: what would happen?

    .. if a globalised patchwork of supposed democratically inspired superlatives were to think they added up to a clue: what would be the discoursive result?

      WE DEMAND baked beans in absurdly small tins let alone the shelled crustacens that do oceanic distances to reach our fat-cat pensioner mouths: the mountain is our ego and once it gets smashed the problem is solved and people actually died for this!

     No one cares: that's the problem.. there is no respect for what grandma and Grandpa went through to get us here!!!!!!1

  22. Tracking the 2C Limit - July 2015

    Dear OPOF,

     Can we please forget the fallacy of the wise mountain-climber always climbing the mountain?

     As someone famous once said: "Not all metaphors bear close examination!"

  23. One Planet Only Forever at 14:08 PM on 28 August 2015
    Tracking the 2C Limit - July 2015

    Digby Scorgie @20,

    Let me try to explain why saying "the task is impossible" is not applicable to this issue.

    The task is to raise awarness of the change of human activity that is required for humanity to have a good chance of developing a lasting constantly improving future for all humanity (which requires a robust diversity of other life on this planet).

    The 2C target is an aspiration and not in the sense of making it to the summit of a mountain. Unlike mountain climbing where the wise climber will 'give up the ascent when conditions clearly are not in favour of success', this is a matter where it is essential to achieve the best possible result (which, by the way, a wise mountain climber will be able to do and the risk takers will not), because the consequences of giving up or taking the risk are truly unacceptable (there will be no 'next chance to reach the summit' and others in the fuure will suffer the consequences of the joy-ride of the thrill seeking risk-taker).

  24. Tracking the 2C Limit - July 2015

    Dear Moderator, I thought the correct way to annotate the graph is relevant, but okay I'll go on to something that is:

    I too would like to see some way of indicating the inherent lag in the system.  However, I've seen estimates of 0.5 degrees already built in, not just 0.3 degrees.  I've also seen comments to the effect that 2 degrees is now unavoidable.  Uncertainties like this probably render the task impossible.

    And before signing off, I'll quickly interpolate my defence (excuse?) regarding Celsius: I did say "a few decades" ago!

  25. Here’s what happens when you try to replicate climate contrarian papers

     Looking at the "many scientific contemporaries" this conjectures that it would be less than a dozen. However, one of them was Kepler. I dont think any contemporary would-be-Galileo has someone in the same order supporting them.

  26. Tracking the 2C Limit - July 2015

    Digby, The only exception made to the space convention is for degrees, minutes, and seconds, °, ', " the symbols for the unit(s) of plane angle. °C is the the symbol for a specially defined SI derived unit "degree celsius". Yes, it's not an SI base unit but it is a clearly defined "derived unit". I agree that this detail is principally a style convention but it's a good one to follow. Number_space_unit. 

    It's very clearly laid out in this text from the Bureau International des Poids et Mesures (BIPM).

    See also

    It's also explained clearly in documents from NIST (National Institute of Standards and Technology) for those who prefer a USA centric reference.

    [And don't get me started on the way people embed C for carbon in units of mass or concentration or what not. That's completely wrong and adds to confusion rather than clarifies.]

    Moderator Response:

    [PS] Fixed link. Please use the link button in the editor to create links.

    And please, no more. Dont derail this thread with offtopic discussion.

  27. Tracking the 2C Limit - July 2015

    We are waking up to the fact that the 2C limit is untenable for continuity of an integrated global modern society.

    Moderator Response:

    [PS] Fixed link. Please use the link button in the editor to create links

  28. New paper shows that renewables can supply 100% of all energy (not just electricity)

    @Michael Sweet

    My numbers for Nuclear power are accurate and for wind power are reasonable.  For nuclear power, average capacity factor (including outage time) has hovered right at 90%.

    As for wind power, I still think 25% is a reasonable estimate, though there are numbers out there that are all over the board:

    Also several sources of data from 2008 suggest Europe was struggling to meet even 20%.  So as we add wind turbines, there is the liklihood that as less optimal locations are selected the current USA CF declines from the current values.

    Moderator Response:

    [PS] Fixed link. Please use the link button in the editor to create links

  29. Here’s what happens when you try to replicate climate contrarian papers

    When you look closely at the surveys of the most qualified climate scientists — those actively doing research and publishing their results in peer reviewed journals — you find 97 to 97.5% who believe that the climate is warming and that man is a major cause and only 1% who reject this finding. The other 1.5 to 2% are the fence sitters — the undecided.

  30. One Planet Only Forever at 23:59 PM on 27 August 2015
    Tracking the 2C Limit - July 2015

    I would like to see the 'lagging' likely temperature increase 30 years later due to a rapidly increasing level of CO2. I am referring to he 0.3 degree C value mentioned in "The 1C Milestone" SkS post.

    As mentioned in that article it is likely that accumulated human impacts to date have produced a 1.3 degrees C warming from pre-industrial levels, not 1.0.

    I am not sure how to best represent it. It is related to the rate of increase of CO2. But it is already in the trend of the temperature history. However, if people are assessing how much more impact can be permitted compared to what has already been created the recognition of the 0.3 C must be included in the evaluation.

    Perhaps the best thing to do would be to identify a 1.7 C threshold line with a note explaining why it is on the chart.

  31. PhilippeChantreau at 23:31 PM on 27 August 2015
    Water vapor is the most powerful greenhouse gas

    Venus is better described as having a bright side and a dark side, because of it slow rotation; talking about "daytime" implies that a location on Venus is going to have diurnal temperature variations as experienced on Earth, while not only it is better described as a "yearly" variation but there is also no significant difference between bright and dark side temperatures on Venus. "Daytime" is not an appropriate qualifier of anything on this planet.

  32. Here’s what happens when you try to replicate climate contrarian papers

    It is interesting that the factor making the paper difficult to get published was that it looked at multiple previous studies. Papers showing an inability to replicate the results of just one study get published all the time... almost routinely. Had it been split into 38 separate papers, each showing the inability to replicate a single previous study, it seems unlikely there would have been any controversy.

    Thus, rejecting the 'composite' study because it didn't seek to perform a statistical 'meta analysis' of 'skeptic' vs mainstream replication rates or some other 'collective result' seems to be missing the point. They rejected it for failure to be what it wasn't... while overlooking that it was perfectly sound and replicable science for the issue it was actually looking at.

    The other objection, that the paper clearly had a 'political' point in looking solely at 'skeptic' papers is true... but should have been irrelevant. Rejecting sound science because it has a political intent is, itself, a political decision.

  33. Tracking the 2C Limit - July 2015

    I'd drop CO2 too.

    However there is an intriguing possibility: Plot

     TCRCMIP5 x log2(CO2(T)/<CO2>1888-1909)

    It then has the same units as temperature and provides an interesting model-obs comparison. Tough to explain though.

  34. Tracking the 2C Limit - July 2015

    @6, ..talking about political targets 3 C is exactly what Bjorn Lomborg was hoping to convince the global voters of democracy that fossil fuels should be allowed to warm our kids earth by.

     I just feel that this exact point needs to be made as science and politics are inextricably linked.

     How much more political can it be to have the good name of a prestigious University used to flog fossil fules all in the name of enriching the elite?!!?

  35. Here’s what happens when you try to replicate climate contrarian papers

    I've read the account by Rasmus Bernestad in RealClimate and am intrigued by the journal shopping that took place in efforts to  find a journal that would accept this paper.  Perhaps  unsurprisingly. the journal that finally accepted the paper had the lowest Impact Facor  (1.759) of the five journals approached.  The title of the paper "Learnng from mistakes in Climate Science" is, again perhaps, as applicable to the efforts of the authors in getting the paper accepted as it is to the papers they criticise in their paper.  Quite honestly the efforts seem typical of academics operating under the threat of "Publish or Perish".  That said congratulations to Dr Bernestad for presenting the saga so frankly. I would however ask Dr Bernestad not to use "fairly unique".  Something is unique or it is not. There are no qualifiers

  36. Tracking the 2C Limit - July 2015

    ecwiebe @1

    As a retired technical writer I appreciate your point (3).  I always made sure to keep a non-breaking space between number and unit.  However, there is one exception — or at least there was when I investigated the matter a few decades ago — and that concerns degrees Celsius.  In this case there is no space; in effect, the degree symbol fills the space between number and unit symbol (C).  Interestingly, there is of course no degree symbol when kelvins are used.  I think the anomaly with Celsius arises from the fact that it is a non-SI unit.

  37. Here’s what happens when you try to replicate climate contrarian papers

    M Tucker

    I think Dana's statement that Galileo's conclusions were based on empirical evidence is defensible. After all, he was actually observing the Moon and planets through a telescope. 

    However, I too would cast doubt on the statement that Galileo was supported by "many scientific contemporaries". They were just not many scientists around! As far as I know, Jesuit astonomers like Father Clavius, who was respected by Galileo, were willing to compromise on Galileo's theory by treating it as a method of calculation of orbits rather than physically true. However, Galileo was just not the compromising type.

  38. Water vapor is the most powerful greenhouse gas

    PhilippeChantreau @215, perhaps, but half the planet remains in night at all times even so.  I suspect I have missed your point.

  39. Here’s what happens when you try to replicate climate contrarian papers; he stept on some very powerfull toes (and his theory was flawed)

  40. PhilippeChantreau at 14:45 PM on 27 August 2015
    Water vapor is the most powerful greenhouse gas

    Well, personally I think that talking about "daytime" temperature on a planet that takes longer to rotate on its axis than to orbit around the Sun speaks more about one's ignorance than any other enormity he could profer...

  41. Water vapor is the most powerful greenhouse gas

    re:AJ Virgo @212, I can well imagine a stunned silence when it was claimed the daytime temperatures of Mecury and Venus being "about the same" disproved the existence of a atmospheric greenhouse effect, but it is the stunned silence that shows complete disbelief that anybody could so flaunt their ignorance of basic science.

    Let's start with the basics.  Mercury is closer to the Sun than Venus.  Therefore, because of the inverse square law, Mercury recieves far more radiation than Venus.  Three and a half times as much per meter squared, as it happens, and six and two/thirds times as much as is recieved by the Earth per meter squared.  All else being equal, as a result of this we would expect the skin temperature of Mercury to be 120 K greater than that of Venus, and 169 K greater than that of the Earth.

    All else is not equal, of course.  In particular, the bond albedo of Mercury is just 0.068, compared to 0.9 for Venus and 0.306 for Earth.  That is, Mercury reflects away just 6.8% of radiation that falls on it from the Sun, compared to 90% for Venus and 30.6% for the Earth.  Once we factor that into the equation, we expect a skin temperature of Mercury of 439 K, compared to just 184 K for Venus, and 254 K for Earth.  Ergo, absent any greenhouse effect, we absolutely do not expect the daytime (and night time, winter or summer) surface temperature of Venus to excede the maximum surface temperature on Mercury, but at 737 K, it does indeed exceed the 700 K maximum daytime temperature of Mecury.

    Having ignored elephants like the effect of Sun-planet distance on radiation recieved, and the effect of albedo, it is no surpise that AJ Virgo also ignores subleties such as heat distribution, comparing daytime maximum temperatures with Venus mean annnual temperature (which coincidentally is also its daytime maximum temperature due to its thick atmosphere and strong greenhouse effect).  For what it is worth, the skin temperature, on a planet with no atmosphere, equals the surface temperature.  As it happens the observed mean surface temperature of Mercury is 440 K, near identical to the calculated vaue.

  42. Water vapor is the most powerful greenhouse gas

    AJ Virgo @212...  "We have been led to believe that the warming effect of CO2 is linear but it's logarithmic..."

    Nope. The entire premise of climate sensitivity is a function of a change in temperature per doubling of CO2. That is, in itself, is a logarithmic function.

    And that very premise dates back to Svante Arrhenius in the late 1800's through the early 1900's.

  43. Water vapor is the most powerful greenhouse gas

    We have been led to believe that the warming effect of CO2 is linear but it's logarithmic, decreasing in proportion to saturation. This means that after about 200ppm adding more will do near nothing.
    Obviously if this were not true there would be no life on Earth.
    This can be seen with Venus and Mercury which have about the same daytime temps yet Venus has an atmosphere %96 CO2 and Mercury near none.
    This fact was brought up a few years ago and there was stunned silence then and stunned silence since, it killed the debate stone dead.
    Laughably the politicians soon started saying "The debate is over" but they didn't know why !

    Moderator Response:

    [TD] See the post "Is the CO2 Effect Saturated?" Read the Basic tabbed pane there, then watch the video lower on that page. Then read the Intermediate tabbed pane, then the Advanced tabbed pane. Then read the article linked in the "Further Reading" box below the video. Then if you still are unconvinced, say so in a comment on that post's thread, not this one, and I will point you to two articles on and some on Before commenting again, gain some knowledge and lose some attitude.

  44. Ice age predicted in the 70s

    LizR @58, Scientific American republished that article in 2008 "to offer an historical perspective on some of the issues being discussed at the United Nations Framework Climate Change Conference".  The full original version including charts and illustrations has also been reproduced as a PDF here.

  45. Tracking the 2C Limit - July 2015

    Tom @11... That one is going to take a little more processing on my part. Let me work on it.

    Tom @12... You know, I had thought of the same thing, but I'm having some trouble with Apple Numbers (not using Excel) where there seems to be a bug when I select log scale. When I select that the y-axis defaults to a min of 100 and a max of 1000, which totally messes up the chart. 

    That one is going to take some work too.

  46. Ice age predicted in the 70s

    This looks to be the G Plaas paper. You can find references and links to these early papers here including this one. See also the wonderful Weart book "The discovery of global warming".

    For the sciam reference, see here. A republish of july 1959 article.

    Note that this is offtopic. Please do not continue discussion in this thread.

  47. Ice age predicted in the 70s

    Does anyone have a link to the Scientific American article from the 1950s (or 60s?) called "Carbon Dioxide and Climate". So far I have seen only the attached rather blurred scan. I would like to read it (and find out the date!)


    SciAm article from the 1950s on climate change

    Moderator Response:

    [PS] Fixed image size

  48. Tracking the 2C Limit - July 2015

    Rob, with regard to CO2, it would be better to plot the log of CO2 against temperature rather than just CO2.  If you want to use a linear measure, cumulative emissions has at least some scientific support as having an approximate linear relationship with temperature.  As it relates to the chart, I can understand your reasons for not including a second set of values on the y-axis, but if you do not you need to be more explicit about how CO2 concentration values are related to the temperature values.

  49. Tracking the 2C Limit - July 2015

    Rob, using the Mann 2008 Global EIV reconstruction, the 1736-1765 average is -0.11 C using the same baseline as you do above.  If we renormalize the reconstruction against the GISS LOTI, that becomes -0.12 C.  That renormalization is appropriate given that the reconstruction is normalized against HadCRUT3, which distorts its values very slightly due to the reduced twentieth century trend shown by that (now obsolete) temperature index.  In either event the difference from your assumed preindustrial temperature as reflected by your baseline is small, but your baseline will consistently underestimate the how near we are to the 2 C 'target'.

  50. Tracking the 2C Limit - July 2015

    jphsd... Yes, I'm aware of Victor & Kennel. But Stefan Rahmstorf did an excellent response to their paper on Real Climate titled, Limiting global warming to 2 °C – why Victor and Kennel are wrong. 

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