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Those pesky scientific facts…

Filed under: — gavin @ 5 March 2006

We would be remiss in not bringing today’s Doonesbury cartoon to a wider audience.

Hat Tip: Pharyngula and Hank Roberts.

88 Responses to “Those pesky scientific facts…”

  1. 1
    John Wiley says:

    Yes, I get the cartoon. Is it science or is it not? Time will tell, many now accepted ideas were “just not scientific” when they were first developed–until we needed them!

  2. 2
    Eli Rabett says:

    More to the point John, how many “just not scientific” ideas were just wrong (for a semi-comprehensive, but amusing listing see

  3. 3
    John Hunter says:

    Sorry, my eyes aren’t so good nowadays, but is the guy with the calculator named Stewie or Stevie?

  4. 4
    Chris says:

    Stewie, definitely Stewie. Does it matter for any particular reason?

  5. 5
    Lisa says:

    And let’s not forget that what has often been accepted as scientific fact is later debunked. And the corollary, what often passes for scientific “fact” is not fact…….

  6. 6
    Hank Roberts says:

    Reminds me of this, somehow:

  7. 7
    Nick says:

    Funny, I could have sworn it said “Stevie”…

  8. 8
    Max Schwing says:

    Hmm, if I understand it right, then ANY politized science is bad, because it tends to stroll off the facts (and this is also in respect to pesticides, or nuclear power (where facts are oftened ignored)).

    I think they have a deal, especially when it comes to religion, but it’s not the religious right that critisizes man-made climate-change, but rather sceptics…

    However, I like this cartoon, especially if one followed the battle between creationism and evolution or the neglect of facts and complexity in politics at all… (As if Scientists can proclaim one easy step to solve the problems, as if a democratic consensus in science mattered at all…)

  9. 9
    nanny_govt_sucks says:

    Here’s another cartoon which I feel pretty well sums up the CO2/GW hypothesis:

  10. 10
    Peter Backes says:

    Re: 9
    I’m not sure I get the point. Atmospheric C02 goes up, temperature increases – where’s the miracle? The theory has been around for years.

    I do think Gary Trudeau misses an important point, however. ‘Situational Science’ is itself controversial. Mr. Trudeau should give its detractors equal time in his strip.

    Confused? Not thinking about global warming anymore? That’s the point…

  11. 11

    Time will tell, many now accepted ideas were “just not scientific” when they were first developed–until we needed them!

    since they are plentiful, at least from your perspective, you wouldn’t mind giving some specific instances, would you? of SCIENCE now, not inventions or technology.

  12. 12
    per says:

    Re: # 11
    1) The idea that stomach ulcers are caused by bacterial infection was roundly ridiculed, and got the Nobel recently.
    2) Tectonic plates
    3) That mitochondria are prokaryotes living in a eukaryotic cell
    4) that the earth goes round the sun
    I think that’s a few to be going on with :)

  13. 13
    Don Baccus says:

    Re #12: Which of your examples were once considered scientific fact, then later debunked?

    I was under the impression that each of your four hypotheses, while originally controversial, became accepted after a lot of research and hard work, and have yet to be debunked.

    How does this differ from the AGW hypothesis? While originally controversial, it has become accepted, and has yet to be debunked …

  14. 14
    Don Baccus says:

    Oops, I mistakenly thought posts #11 and #12 were referring to post #5 … my goof.

    Scratch that post if you can :)

  15. 15

    regarding “(1)”, that’s “normal science”. that is, it is a reasonable hypothesis, however skeptically it was received, which was proven true. the Nobel affirms that.

    “(2)” was surely a paradigm shift, but in actuality, it had little or nothing to do with Wegener’s “continental drift” hypothesis, which is probably what you consider the object of ridicule in that case. indeed, plate tectonics was the achievement of a single guy, J Tuzo Wilson, somewhat anticipated by Arthur Holmes and David Griggs. even so, if you consider Wegener, his ideas were only ridiculed in the United States but were accepted in Europe. and, of course, Wilson was trying to explain the new evidence from seafloor spreading measurements and geomagnetic reversals, not merely the origin or shape of continents.

    “(3)” isn’t quite correct. mitochondria are not independently living organisms. for example, they’re not capable of apoptosis apart from their host cell, nor do they undergo mitosis except when signalled by the host. the idea of a prokayotic origin of mitochrondia is widely accepted today but that’s because endosymbiosis is recognized now as a more widespread biological relationship than it once was, notably with respect to chloroplasts, plastids, and kleptoplastidicity. the idea is if the mechanism exists today, why couldn’t it exist then?

    “(4)” is actually quite old, traceable at least to ancient Greece. it’s just too bad the result was forgotten in the following centuries because it was inconsistent with a particular religious world view and its accompanying philosophy.

  16. 16
    nanny_govt_sucks says:

    “Atmospheric C02 goes up, temperature increases”

    Like in the 1940’s, 50’s and 60’s?

  17. 17

    i think from the standpoint of policy the emphasis upon whether or not there is warming due to anthropogenic sources is misplaced. what is far less controversial is that there is warming. whether or not the warming is natural or anthropogenic, its consequences are all the same.

    as a result, i think the effort oughtn’t be upon trying to mitigate anthropogenic sources, although desirable in the long run. instead, what’s needed is a major program to begin to prepare for its many deleterious consequences. warming is irreversible now.

  18. 18
    Hank Roberts says:

    > 1940’s, 50’s and 60’s?

    Good for you, Nanny, you’re thinking scientifically.

    “Since 1751 roughly 290 billion tons of carbon have been released to the atmosphere from the consumption of fossil fuels and cement production. Half of these emissions have occurred since the mid 1970s.”

  19. 19
    Hank Roberts says:

    Tsk! I didn’t cite that properly.
    Here you are:
    Data so you can check the numbers:

    CITE AS: Marland, G., T.A. Boden, and R. J. Andres. 2005. Global, Regional, and National CO2 Emissions. In Trends: A Compendium of Data on Global Change. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tenn., U.S.A.

  20. 20
    nanny_govt_sucks says:

    Like in the 1940’s, 50’s and 60’s? … when global temps DECREASED?

  21. 21
    Coby says:

    Hi nanny,

    There are many factors that affect the global climate, CO2 being just one, though at the quantities we are plaing with it is a critical one. Given this fact, it is not the brick wall you make it out to be that for a period of time other forcings were able to dominate, especially as this was relatively early on in the CO2 pulse we are in the midst of (hence Hank’s references).

    Check here for an overview of the various forcings over the last century:

    As you can see, stratospheric aerosols provided a very strong negative forcing at around the time you note global temperatures fell slightly (haven’t we covered this before??)

  22. 22
    nanny_govt_sucks says:

    “haven’t we covered this before??”

    With some hand waves.

    “As you can see, stratospheric aerosols provided …”

    The magic aerosols again. The problem is that the regions where aerosols are produced show warming not cooling in recent times, and the 1940-1975 cooling trend is seen in many parts of the globe where aerosols were not a factor. So your claims are not backed up by any observations that I’m aware of. So we still have:

  23. 23
    Coby says:


    This is not a problem because the aerosols do not hover over the place they are produced. Think of Pinatubo! It, like any large volcano, had a global effect despite being a rather local phenomenon. That seems to me a reasonable observation to back up my point.

    What do you say? Your expectation is that stratospheric aerosols only affect the region in which they originate but obsevations don’t support this. Can we put that misconception to rest?

  24. 24
    Hank Roberts says:

    I think Nanny’s getting it. Yes, we had a slow trend of cooling for a while there — lots of coal being burned, lots of sulfur. Heck, lots of high sulfur diesel oil too, that’s what’s burning in the furnace in the house I grew up in still, that’s what the farm coop delivers for heating oil. Corrodes the heck out of the chimney, too, that sulfur.

    Half the CO2 produced from fossil fuels burned up til the mid-1970s, most of it the sour oil and coal — and a slow cooling trend if anything.

    Then comes the mid-1970s. The other half of the CO2 produced from fossil fuel happens starting then. More refined fuel. Kerosene in jet engines, not just in oil lamps. Hugely more fossil fuel burned, as much in thirty years again as had been burned before. Big change.

  25. 25
    Stephen Berg says:

    In the next few years, we should be able to completely refute the argument that solar fluctuations are a primary reason for the change in surface temperatures. Apparently, the “Solar Minimum has Arrived”:

  26. 26

    Re #23,

    Coby, the Pinatubo was a stratospheric injection of a lot of SO2 at once, which spread over both hemispheres and lasted several years as sulphate aerosol. The human induced SO2 is emitted in the lower troposphere and has an average lifetime of only 4 days, before raining out. Thus the human made aerosol cooling (and changes in cooling with changes of emissions) should be seen in the main wind direction of the sources, which are by far largest in the NH. But temperatures (including ocean heat content) are increasing faster in the NH…
    See further my comment on aerosols on RealClimate

  27. 27
    Lawrence McLean says:

    I have a question relating to a point that the skeptics troll out. It is the issue of the predicted Ice-age in the 1970’s. Does anyone know who was the author of this theory and why it was raised? It is raised by the skeptics now as an attempt to discredit the current climate scientists and their findings.

    [Response: See here – it’s a complete red herring. -gavin]

  28. 28
    Almuth Ernsting says:

    Re 27 and ideas in the past:

    I spent a couple of interesting hours recently looking through British geology textbooks from the late 50s and mid-70s. Interestingly, none of them suggested a coming ice age (not for tens of thousands of years anyway). Both explained that CO2 levels were rising and that one would assume this to lead to higher temperatures, but that this seemed to be cancelled out because the ocean took up so much of our emissions and because of human sulphur aerosols off-setting the warming. Not far off the mark, as far as the situation at that particular time went. Fascinatingly, the book from the mid-70s said that there was one climate scientist – Wally Broecker- who predicted that the greenhouse warming was on the verge of overtaking the aerosol cooling effects and that by the year 2000 the planet would be warmer than it had been in 1000 years.

    Almuth Ernsting

  29. 29
    Pat Neuman says:

    re 27. The global cooling myth (RC Jan. 2005) says: “people were well aware that extrapolating such a short trend was a mistake (Mason, 1976).”

    I too am aware that extrapolating short trends can be a mistake but I am also aware that trends should not be taken lightly when a lot is at stake concerning the outcome.

    During recent decades, overall temperatures and humidity have been increasing while variance (annual, monthly, diurnal) averages have been decreasing.

    Globally averaged SST has increased about 1 Deg C over the last 50 yrs.

    Global warming feedbacks are expected to increase the rates CO2 accumulation and global warming in this century (and next?).

    With decreasing variance in annual (and decade) temperature, predictive capability should increase.

    In Science, James C. Zachos, et. al, (June, 2005): [During the
    Paleocene-Eocene thermal maximum (PETM), sea surface temperature (SST)
    rose by 5 Deg C in the tropics and as much as 9 Deg C at high latitudes, whereas bottom-waters temperatures increased 4 to 5 C. The initial SST rise was rapid, on the order of ~1000 years, although the full extent of the warming was not reached until some ~ 30,000 years later.]

    The PETM was an especially intense (rapid rate) warming period in
    Earth’s past.

    In “Ancient Climate Studies Suggest Earth On Fast Track To Global Warming”, Santa Cruz CA (SPX) Feb 16, 2006″

    [Human activities are releasing greenhouse gases more than 30 times
    faster than the rate of emissions that triggered a period of extreme
    global warming in the Earth’s past, according to an expert on
    ancient climates.

    “The emissions that caused this past episode of global warming
    probably lasted 10,000 years. By burning fossil fuels, we are likely
    to emit the same amount over the next three centuries,” said James
    Zachos, professor of Earth sciences at the University of California,
    Santa Cruz.]

    The rate of ocean surface warming of 1 C over the last 50 years (fig.
    at NCDC) when extended 1,000 years out = 20 Deg C, which would be
    around 4 times the rate of warming which took place during the
    especially intense period of rapid global warming for the first 1,000
    years of the PETM.

    It is likely that there was a substantial amount of ice near the poles during the period which preceded the global warming that led to the PETM (i.e. prior to PETM warming, global climate state may not have been greatly different than the current?). “A relative sea-level fall (~30 m) immediately preceded the late Paleocene thermal maximum, during which sea-level rose again by ~20 m. This rise may have been eustatically controlled, possibly through a combination of thermal expansion of the oceanic water column and melting of unknown sources of high-altitude or polar ice caps in response to global warming.”

    The rate of ocean surface warming of 1 C over the last 50 years (fig.
    at NCDC) when extended 1,000 years out = 20 Deg C, which would be
    around 4 times the rate of warming which took place during the
    especially intense period of rapid global warming for the first 1,000
    years of the PETM.

    … “Based on sea-level history, we have proposed that ice sheets existed for geologically short intervals (i.e., lasting ~ 100 ky) in the previously assumed ice-free Late Cretaceous-Eocene Greenhouse world (36).” … These ice sheets existed only during “cold snaps,” leaving Antarctic ice-free during much of the Greenhouse Late Cretaceous-Eocene.” … 25 Nov 2005 article in Science, The Phanerozoic Record of Global Sea-Level Change (Miller, K.G. et. al.).

    These scientists used “cold snaps” to mean lasting 100 ky. Makes one wonder what they’d call the thawing rate over the last 50 years.

    Based on the analysis above, it is unreasonable to think that rates of warming have been more rapid than over the last 50 years, thus it is also unlikely that such rapid warming as in recent decades is related to non anthropogenic causes, and likely entirely or nearly entirely due to human activity. It is not unreasonable, given the potential outcome, to consider a 50 year trend in evaluating futures, along with climate modeling results. I also think it may be a mistake to take the recent 3 year analysis of conditions in Antarctica with a grain of salt. It would be unfortunate for climate scientists, fearing faulty ridicule concern the global cooling myth scare, to underestimate global warming signals that seem drastic for fear of being ridiculed. Such has been the case, frequently, in hydrologists under predicting extreme flood level out of fear from being called chicken little by their coworkers, colleagues and/or supervisors.

  30. 30
    Tom Fiddaman says:

    Re 28 (old geology texts)

    Cool. Can you provide citations? I’d love to find copies and post some excerpts.

  31. 31
    Ike Solem says:

    Here is a comment I recall a few geosciences department scientists harping on about five years ago:

    “We know for sure that the Antarctic system is isolated from the effects of global warming due to the influence of the circumpolar Antarctic current. We are also sure that the Greenland ice sheet is stable and won’t be melting anytime soon. So these ideas of rapid climate change are really overblown.”

    So… it looks like they were entirely wrong. I should also mention that one of these guys was working summers at a Houston oil firm – a lucrative position. Yes, scientists are subject to political and financial pressures, and these pressures often lead them to sing the song they think their audience wants to hear.

    Take a look at the March 06 Washington Post story on the gutting of various environmental satellite programs:

    This is the idea behind this kind of science budget: what we don’t know won’t hurt us. In fact, we don’t want to know! Those pesky scientific facts…

  32. 32
    Chuck Booth says:

    Re #12 1) The idea that stomach ulcers are caused by bacterial infection was roundly ridiculed, and got the Nobel recently.

    I think it is inaccurate to say that the idea that stomach ulcers are caused by bacterial infection was “roundly ridiculed.” In 1983, Drs. Barry Marshall and Robin Warren reported that they had identified a bacterium that was responsible for stomach ulcers. Their report was met with both interest and skepticism – the latter because Marshall’s and Warren’s findings defied conventional wisdom that bacteria could not survive in the highly acidic environment of the stomach, and earlier studies on stomach contents had offered no convincing evidence that bacteria were present. Marshall and Warren conducted a series of careful experiments (reported in The Lancet and Annals of Internal Medicine in the late ’80s and early ’90s) to convince themselves and their critics that yes, bacteria can live in the stomach (under the mucus layer, where they are protected from the HCl), and yes, they do cause ulcers (and possible cancer). This seems to be a textbook example of the way science is supposed to work.

  33. 33
    Hank Roberts says:

    > Washington Post
    This sounds familiar, doesn’t it?
    “… _Last month Scripps’ Valero was notified that the Deep Space Climate Observatory, a project he has led for more than seven years, would be canceled. The spacecraft has already been built, but NASA is reluctant to spend the $60 million to $100 million it would cost to launch and operate it. … it would have hovered between Earth and the sun at a distance of roughly a million miles, it would have been able to observe the entire sunlit surface of the planet constantly.”

    This is the L1 position — same satellite discussed earlier under other names, cancelled yet again? Or with extreme prejudice this time, have they decided to quit paying the storage locker rent and landfill the satellite?

  34. 34
    Coby says:

    Thanks for the information, Ferdinand. I accept that my volcano comparison may not be appropriate. I clearly don’t know enough about aerosols and won’t comment further til I can rectify that.

    [Response: Coby — don’t feel too bad. You weren’t entirely right, but Ferdinand’s comments about aerosols are rarely completely on the mark either. I applaud his efforts to read the literature, but am a little frustrated by his refusal to learn from what people tell him. Nonetheless, read the papers Ferdinand mentions. He’s often right about what’s worth reading, even if often wrong about the implications. With regard to the pattern of mid-20th century cooling, as compared to the aerosol response, there is no question that there are some strong features of the observed cooling that are consistent with aerosol response. These come out most impressively in Tapio Schneider’s analysis of 20-th century variability, which appeared a while ago in J. Climate. This was a completely model-free data analysis that yielded a pattern very much like the expected aerosol cooling. Now, there are some places where you get cooling in the observations that isn’t clearly connected with a local aerosol effect. This is hardly surprising. First of all, the mid-20th cooling is not sole-ly a response to anthropogenic aerosols. You have variations in solar forcing and volcanic activity as well, which also is being offset in some places by CO2 effect more than in others. Moreover, when you change one thing in the atmosphere, things like the Hadley cell response, Rossby waves, jet streams, ice movement all redistribute the response, which means you can’t necessarily match things feature for feature with the forcing. On top of it all, the signal at that time is very small, so small errors in the SH observations, or internal variability, can cloud the signal. Much of this was very well discussed in the 2001 IPCC report, and no doubt the forthcoming report will be even more complete. Add to that the possibility that there are some forcings that aren’t done completely right in the models yet, probably — black carbon and indirect aerosol forcing. I’d worry if the match were too perfect. So, we match a lot of the extreme pattern of cooling, and we match the global mean. More importantly, the much bigger late-20th century warming is fingerprinted very well. There’s stuff to think about, which is why people are still working on this, but nothing that casts any real doubt on the aerosol hypothesis. Again, if somebody thinks they have a better theory for mid-20th century climate, they ought to turn it into mathematics and play for real. –raypierre]

  35. 35
    Gerald Machnee says:

    Re the cooling and Ice Age – National Geographic did an article on it in 1976. I do not remember what the split was in scientists agreeing and disagreeing.

  36. 36
    Richard Ordway says:

    1970’s global cooling?

    You want to see some deliberate obsfurication of science by people who are directly manipulating you personally? Read on:

    Deliberate omission of a sentence from the U.S. National Science Board’s writing.

    “In 1972, the U.S. National Science Board concluded that “judging from the record of the past interglacial ages, the present time of high temperatures should be drawing to an end…(included punctuation-Richard)leading into the next glacial age! However, the warm 1980s…(my punctuation-Richard)and it concludes “It’s no coincidence that “greenhouse effects” seem to appear after warm spells only to quietly disappear a few years later”, “Skywatch West: The Complete Weather Guide:”, “Changing Climate” chapter. published in the last four years. Richard A. Keen,

    So the U.S. National Science Board stated in 1972 that we are going into an ice age, right? Well, he’s a meterologist, a scientist and it’s a published book, so it must be true, right?

    Do you want to see the very next sentence that he deliberately left out according to a direct full quote from Wipedia that directly says the opposite?

    “In 1972, the U.S. National Science Board concluded that “judging from the record of the past interglacial ages, the present time of high termperatures should be drawing to an end…(origional punctuation-Richard)leading into the next glacial age.”

    Next are the direct following words omitted by Keen. “However, it is possible and even likely that human interference has already altered the environment so much that the climatic pattern of the near future will follow a different path.”

    So, now Keen’s (who is printing in a non-peer-reviewed journal) reader thinks that the official U.S. National Science Board says that we are going into an ice age…but it is a deliberate lie…and unscientific.

    Many statements like this create and spread scientific myths by people who cannot print real science in peer-reviewed journals because their evidence does not stand up under scientific scrutiny.

    This is not science. This is terribly damaging personal politics against the nations’ interests and against you personally. You need to start out with real facts. If you want to know what science really thinks, read the peer-reviewed journals, not political articles and books put out by idealogues.

  37. 37
    Lawrence McLean says:

    Thanks Gavin, much appreciated.

  38. 38
  39. 39
    Lawrence McLean says:

    It is a skill of animals including us to be able to find patterns that are hidden in a lot of noise. Example, being able understand someone at a noisy party. From my own observation I sensed a change in climate in the late 1970’s. By the way, I grew up in Wollongong, in south-eastern Australia. One change was that obvious cold fronts stopped coming through, these were a regular and very familiar weather pattern, especially in the summer time (at least one per week) until the late 1970’s. These storms were quite wonderful, their features were wind that was: strong (but not dangerous), steady and from one direction only, heavy but short lived rain and when they passed the air was cool and crystal clear. They had the affectionate name of “southerly buster”. The other noticeable change at that time was that winters used to come suddenly. Although the average climate statistics show a steady decline in temperatures from Summer to Winter weather, the actual pattern, prior to he late 1970’s was that we would get a last summer southerly buster that would herald wintry weather. Obviously the day in the year that had this event varied from year to year which meant that long term averages masked this pattern. Nowadays however, we get a slow drift into winter weather.

    My own observations are the primary reasons why I believe the Climate scientists.

    The question that I asked in this thread (#27) regarding the 1970’s ice age story, was the last point raised by the skeptics that I had not been able to find any information about. That has now been clarified for me, thanks again.

    In summary, from my review in reputable sites I have found that EVERY single point raised by the skeptics is rubbish.

  40. 40
    Gerald Machnee says:

    Re #39 – **In summary, from my review in reputable sites I have found EVERY single point raised by the skeptics is rubbish.**
    Riding on the bus I hear “the weatherman is ALWAYS wrong”
    Neither you or the riders have documented the data. There is intelligent discussion on both sides.

    [Response: There is intelligent discussion on many issues. However, the majority of the skeptic ‘talking points’ are red-herrings, strawmen or simply wrong. – gavin]

  41. 41

    Re #16 and “Atmospheric C02 goes up, temperature increases” versus nanny’s “Like in the 1940’s, 50’s and 60’s?”

    Okay, modify the statement to, “when CO2 increases, the temperature of the ground increases, all else being equal.” The point is, in the ’40s through ’70s, negative forcings dominated. You bring up an objection, the scientists find an explanation for the anomaly (aerosols), and then you reject their explanation with your comment about “magical aerosols.” It just seems to me you want to believe what you want to believe and the hell with the evidence. The scientists can’t win.

    A lot of cities were burned in the 1940s — Hamburg, Dresden, Tokyo are the ones that come to mind just offhand. We also bombed the oil fields at Ploesti. There was a lot of debris in the atmosphere in that period. It’s no coincidence that when governments began controlling particulate pollution, in the 1970s, the upward temperature trend started up again.

    More CO2 in the air, hotter ground, all else equal. Scientific fact. Reject it at the cost of everybody knowing you’re an ideologue who puts his fanaticism ahead of empirical evidence.

  42. 42
    Pat Neuman says:

    re 34.

    I gave a different explanation than the aerosol hypothesis for the early-mid 20th century climate, link (3) below.

    Warmer 1930s-mid 1950s: (1) “rise in solar forcing during the early decades of the 20th century” (2) El Ninos: early 1940s – early 1950s

    Cooler mid 1950s to mid 1970s: La Ninas (2)

    (3) .. comments 117, 141

    Also see:

  43. 43
    Gerald Machnee says:

    Re #40 Response by Gavin: Check “Hurricanes and Global Warming – Is there a Connection?” Read the last several posts where one of your contributors was suggesting that the Hurricane off Brazil was caused by global warming. Then there was another post wondering if the earthquakes were caused(strengthened) by typhoons (also suggesting they were strengthened by global warming).
    Your comment applies to both sides.

  44. 44
    Mikel Marinelarena says:

    Trying to clarify and quantify what the pesky Scientific Facts exactly are I have done a lot of reading of past threads in this website and found this assertion by Gavin:

    “…there are good reasons to expect CO2 levels to continue to grow. Any conceivable growth rate (even a constant 1.5ppm/yr) will add by 2050, another ~1W/m2 to the climate forcing. Add in the current radiation imbalance of ~1 W/m2, you have at least 1.5 deg C surface warming to come (assuming a canonical 0.75 C/W/m2 sensitivity)”.

    So Gavin predicts a warming of the surface temperature of *at least* 1.5 deg C for the next 5 decades or so, which is very much in line with the IPCC mean estimate of about 3 deg C for the next 100 years. However, the current warming of the surface is accepted to be around 0.18 deg C/decade (even less for the lower troposphere, according to most measurements, even though GCMs generally predict a tropospheric amplification of AGW, especially in the tropics). This means that, at the currently observed warming rate, Gavin’s most conservative predictions will actually fall short by around 40%.

    Am I right in assuming that we should thus see a rapid increase of the GW trend in the coming years/decades? Is it OK to infer that, failing some major negative forcing (such as a big volcano eruption or solar irradiance decrease) there’s no reason for this 0.18 deg C/decade GW not to increase from now on? Should the models/physics on which Gavin’s predictions are based be assumed wrong if the said increase is not realized in as short a period as, say 5 or 10 years (absent the above mentioned negative forcing/s)?

    If my reasoning is correct we might actually be close to finding out how indisputable the pesky scientific facts are.

  45. 45
    Dano says:

    RE 43:

    Two economists were walking down the street when they noticed two women yelling across the street at each other from their apartment windows.

    “Of course they will never come to agreement”, stated the first economist.

    “And why is that”? inquired his companion.

    “Why, of course, because they are arguing from different premises”.

    Maybe the difference in your ‘two sides’ has to do with the tenacity of holding on to information. I wonder if the folk who read the (few) media reports of AGW=tsunami still believe the “connection” after reading the corrections, backed by scientific analysis.

    Just a thought.



  46. 46
    Steve Sadlov says:

    RE: #39. Well then based on your logic, if I look at the weather at my locale over some 40 years, then we are surely on the verge of a glacial. But obviously this is only a local observation, subject to significant non-global factors. This is something where I can sheepishly say I agree with Dano….. :-)

  47. 47

    Re # 44

    No, your reasoning is incorrect. The warming lags the forcing, as the ocean heat capacity slows the response down. We have some unavoidable additional warming, and the additional 2 W leading to 1.5 C seems a realistic estimate of what we cannot avoid.

    However, just as today we see an imbalance, in 50 years we will also see an imbalance. The total warming does not show up until the system re-equilibrates, several decades thereafter.

    If we implement sufficiently large cuts in CO2 emissions as soon as is feasible without major economic disruptions, we *eventually* see (according to the conventional wisdom) about 1.5 C of additional warming, about double what we have already seen. Most of that effect will occur within three decades thereafter. Which leaves us neatly in the right ballpark. 8 * 0.18 = 1.44 , so no major acceleration of the trend is required.

    If the estimated sensitivity of surface temperature per TOA W/m^2 is high or low, the amount of temperature change we are already committed to goes up or down.

    In fact, the emission scenario discussed here is very optimistic, so we do in practice expect the trend to accelerate.

  48. 48
    Pat Neuman says:

    re 39. Lawrence, you wrote that from your own observation you sensed a change in climate in the late 1970’s. When did you become convinced that rapid global warming was happening? When did you become convinced that greenhouse gas emissions from using fossil fuels for power generation is causing rapid global warming? Have you made an effort to reduce your GHG emissions and tried to convince others to reduce GHG their emissions? I’d like others to share their experiences on these questions, and I would too if I thought others wanted to see that.

  49. 49
    David B. Benson says:

    Local climate changes —

    In the 35 years I have lived here, it seems that the climate has indeed warmed. Milder, dryer winters are particular noticable but it seems to me the growing season is longer. In the 1970s tomatoes often froze and it was necessary to pick the whole vine to bring it indoors. No longer required.

    Since coming here I have always walked to work. Should get around to more insulation in the attic.

  50. 50
    Richard Ordway says:


    Re. Comment by Hank Roberts


    This is a National Geographic Magazine (NG) article reprint that I have read before. It is a “public” magazine….not considered a real peer-reviewed scientific journal by the scientific community. NG can print whatever they want. It is not “Science”, “Nature”, “Journal of Geophysical Letters”, etc.

    In fact, this lie was given at Congressional testimony as well as in the Washington Post.

    …and he got away with it. Check this exact Congressional record with the US Library of Congress as I personally did.

    “patterns and perspectives in environmental science: national science board, 1972. Lib. of Congress cat 73-600219. Part III, chapter 1, p55.”

    The whole deleted paragraph is there.

    You can email them (Lib. Congr.) the request and get a fax or copy of it, etc. Look at their website and request a copy of “Pg 55”.

    Do a Google search on these exact words and you will see who is lying to you…

    “Judging from the record of the past interglacial ages, the present time of high temperatures should be drawing to an end … leading into the next glacial age.”

    They censor out the following sentence,

    “However, it is possible, or even likely, that human interference has already altered the environment so much that the climatic pattern of the near future will follow a different path.”

    This changes the meaning 180 degrees from “Scientists think we are going into global cooling in the 1970s” to scientists did not say this at all.

    These people/organizations that show up on Google with this search think they have a heck of a lot of money and ideology to lose.