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New public opinion poll on global warming

Filed under: — gavin @ 23 August 2006

There is a new Zogby poll on public attitudes in the US towards global warming and the potential connection between severe weather events and climate change.

Unsurprisingly to us (but maybe not to others), most of the US public feel that global warming is happening (around 70%), and roughly the same amount of people report being more or much more convinced of this over the last two years.

More interestingly, the pollsters asked whether people believed that global warming was having an effect on intense hurricanes, droughts, heat waves and the like. Again, roughly 70% of people thought that global warming was having either some effect or a major effect on these weather extremes (note that the question was not phrased to ask whether any specific event was thought likely to have been caused by global warming (which was probably a good choice)).

This begs the question whether people’s experience of severe weather has convinced them that climate change is occuring. Televangelist Pat Robertson, for instance, said very recently that it was the latest heat wave that finally convinced him. I think this is likely to be true for most of the public who are not following the issue very carefully (which is most of them of course!). The most significant single event in this context was probably Katrina, regardless of how much climate change can or can’t be associated with Katrina the Hurricane (let alone Katrina the Disaster!).

I would guess that this is likely to be a very common way for public opinion to be formed across a whole number of issues. That is, when a dominant theme is very prevalent across a wide spectra of media, everyday occurrences or new information are often processed with that in mind, and given our extraordinary ability to see patterns in noisy data, we often end up associating the theme with our own experiences. Other examples surely abound in medical or political contexts.

Given that pattern, it is probably overly optimistic to expect scientists, who continually stress that single weather events can’t in general be attributed to climate change but that changes in statistics might be, to have much success in conveying these finer points to the public directly. Instead, their skills are probably best used in clarifying these points to those (e.g. journalists, policy-makers) that set the dominant themes in the first place.

102 Responses to “New public opinion poll on global warming”

  1. 51
    Dano says:

    RE 47 (Sadlov):

    How about something more scientific, such as the areal distribution of humanity. A density function of course.


    Most human societies distribute themselves along transportation corridors and proximate to arable land. That is: you must overlay multiple factors requisite for societies to function to gain useful information on the density function returned from your calcs [that is: wrt to high-quality aragle land density function, ‘sprawl’ is likely accurate to a high probability with a high significance].

    But anyway, wayne was using rhetoric to illustrate a tactic. Not every single word written on a blog comment thread can adhere to someone’s purported wishes for every word ever used in a discussion to be scientific. This is not an abstract.



  2. 52
    ike solem says:

    Public opinion is largely modified by reading the newspapers, listening to the radio, and watching television. In this respect, the widespread acceptance of the threat of global warming in Britain is interesting, in that the media coverage has been far more comprehensive and analytical (with some exceptions). For example, see the following reports from Britain:

    “Climate change is a far greater threat to the world than international terrorism, the UK Government’s chief scientific adviser has said.”(Jan 2004)

    “New proof that man has caused global warming, From Mark Henderson, Science Correspondent, in Washington: The strongest evidence yet that global warming has been triggered by human activity has emerged from a major study of rising temperatures in the world’s oceans.” (Feb 2005),,3-1489955,00.html

    “Millions ‘hit by global warming’
    The increase in traffic is going to hamper CO2 targets
    Millions of people in England and Wales are being seriously affected by pollution and global warming, the Environment Agency says.”
    (Jun 2005)


    Oddly enough, the recent paper claiming global cooling of the oceans by Lymann et. al. was prepared after these two reports from Scripps and Woods Hole (to which the above news stories relate):;309/5732/284 (July 2005)
    “Penetration of Human-Induced Warming into the World’s Oceans
    Tim P. Barnett, David W. Pierce, Krishna M. AchutaRao, Peter J. Gleckler, Benjamin D. Santer, Jonathan M. Gregory, Warren M. Washington
    A warming signal has penetrated into the world’s oceans over the past 40 years. The signal is complex, with a vertical structure that varies widely by ocean; it cannot be explained by natural internal climate variability or solar and volcanic forcing, but is well simulated by two anthropogenically forced climate models. We conclude that it is of human origin, a conclusion robust to observational sampling and model differences. Changes in advection combine with surface forcing to give the overall warming pattern. The implications of this study suggest that society needs to seriously consider model predictions of future climate change.” (June 2005)
    “Dilution of the Northern North Atlantic Ocean in Recent Decades
    Ruth Curry and Cecilie Mauritzen
    Declining salinities signify that large amounts of fresh water have been added to the northern North Atlantic Ocean since the mid-1960s. We estimate that the Nordic Seas and Subpolar Basins were diluted by an extra 19,000 ± 5000 cubic kilometers of freshwater input between 1965 and 1995. Fully half of that additional fresh water – about 10,000 cubic kilometers – infiltrated the system in the late 1960s at an approximate rate of 2000 cubic kilometers per year. Patterns of freshwater accumulation observed in the Nordic Seas suggest a century time scale to reach freshening thresholds critical to that portion of the Atlantic meridional overturning circulation.”

    I included some more comments on the Lyman paper at (comment #65)

    I’m guessing that after these two papers were published in Science, some folks at NOAA got together and decided they needed to support a contrary opinion, and made the funding available for that purpose. There is clearly a group at NOAA that has devoted a lot of time and effort to attacking climate research on all fronts – even if they have to contradict themselves to do so. This mimics the approach that the climate skeptics used some years ago to attack the climate models based on satellite measurements of tropospheric warming, one of Richard Lindzen’s favorite topics (which has now been resolved), until his more recent conversion to believing the models over the data. Idee fixe? An inability to accept contrary evidence is a symptom of that malady. (That accusation can fly both ways, but the science supports AGW – it’s just the eventual magnitude that’s debatable). As far as the current ocean warming rebuttal goes, without comprehensive polar region data, I really think that Lyman et. al have a very poor dataset (who can tell?) and their notion of radiative loss to space as an explanation for their results is also unsupported. I’m guessing that they chose their time period (2002-2005) after a first pass at the data. Deliberate selection of a limited number of years to include in their datasets is another hallmark of this NOAA group – what’s next? I’m waiting to see a ‘spotty dataset’ in which inconvenient years are not included in their time spans (Data from 2000, 2002 and 2006 shows a declining trend!).


    To get back to the British media, some news reports are not quite as reliable, for example:

    “The truth about global warming – it’s the Sun that’s to blame
    By Michael Leidig and Roya Nikkhah
    (Filed: 18/07/2004)
    Global warming has finally been explained: the Earth is getting hotter because the Sun is burning more brightly than at any time during the past 1,000 years, according to new research.”

    This has been refuted in quite a bit of detail, and any decent science journalist would have included a less definitive headline (maybe that was the editor’s choice, however). For details see the Realclimate discussion of solar issues and links therein:


    For comparison to the US media, look at what the Houston Chronicle is publishing (excerpted, as you can’t link directly to their archives – quite unlike the bbc) – and to prefix, I think there are other explanations for a reduced hurricane season so far this year:

    “Hurricane forecasts cooling off / Fewer named storms are likely as winds tame heat in the Atlantic, experts now say
    With record-breaking heat waves sweeping the eastern U.S. and Europe, it may seem odd to suggest that a cooler Atlantic Ocean bears responsibility for the subdued start to this year’s hurricane season. But that’s what is happening, forecasters say. Although the northern Atlantic is considerably warmer than normal, the tropical Atlantic – where most hurricanes form – is about 3 degrees Fahrenheit cooler than last year, when a record 28 tropical storms and hurricanes formed.

    As a result, the most well-known hurricane forecaster, Colorado State University’s William Gray, has dropped his prediction for the number of named storms this year from 17, which he made in late May, to 15. The forecast also calls for fewer hurricanes, down from nine to seven, and fewer major hurricanes, from five to three. So far this year, three tropical storms have developed, including the weakening Tropical Storm Chris, slightly more than normal for this time of year. Eight named storms had formed by this time in 2005.

    “Last year was just freakish early on,” said Phil Klotzbach, a research associate at Colorado State who now leads the study for Gray, an emeritus professor. “We’re not expecting anything like that for the rest of this year.” The temperatures are cooler largely because of stronger easterly trade winds, which have kept the Atlantic Ocean churning, bringing cooler water to the top. In addition, the higher surface winds have caused more evaporation, which also cools the ocean off. As a result, the tropical ocean temperatures are just slightly above normal for this time of year.”

    The Houston Chronicle’s choice of experts is not exactly surprising, though it is fairly revealing. I did find the new home of the Reynolds SST at NOAA; here it is: Not very user-friendly. I also wonder if they’ve changed their method of calculating the anomaly? (There is no description of the method that I could find). They’ve also eliminated their archived forecasts from the web-based dataset (because they were so far off for 2005?), and instead include this little disclaimer:

    “If you require archived forecast data prior to January, 2006, please contact Ludmila Matrosova directly at

    What is going on at NOAA?

  3. 53
    Mark Hadfield says:

    Re 52

    You seem to be suggesting that the recent Lyman et al paper on ocean heat content is an attempt at a rebuttal of global warming, hastily prepared by the folks at NOAA in response to papers showing ocean warming. (If I’m mis-stating what you’re saying, please say so.)

    That’s just bizarre. Josh Willis (now at JPL, but previously at Scripps with Dean Roemmich and Bruce Cornuelle) has been working on ways for assessing ocean heat content with Argo floats, XBTs etc for several years. In 2004 Willis, Roemmich & Cornuelle wrote a JGR article showing that the ocean had warmed fairly steadily from 1993 to 2003. Obviously that time series is of considerable interest and would have been extended as new data became available. I expect that Josh would have been surprised as anyone when the next couple of years’ data showed a significant drop. So he published that result along with a couple of new co-authors. Now, those new co-authors are affiliated with NOAA, so *perhaps* they were sent out by the NOAA powers-that-be to turn Josh Willis to the Dark Side. Then again, perhaps not.

    Anyway, the Lyman et al heat content numbers are hardly a refutation of ocean warming or global warming generally. They say that the ocean heat content in 2005 dropped back to the level of 2000, having exceeded this for the years in between. Their significance in terms of climate variability won’t be clear for a few years, until the data and the models have been re-examined and more Argo data have been collected. Furthermore, the heat content and sea-level data, taken together imply that the freshwater input into the Ocean has increased recently, which won’t be good news for the deniers (though of course it could be wrong).

    Re the suggestion that the loss of this heat to space is “unsupported”. Lyman et al point out that there’s nowhere else in the climate system for this lost heat to go, so it *must* have been radiated to space. This doesn’t mean that changes in the Earth’s radiative balance *caused* the ocean cooling–it could have been the other way round.

    Let’s just assume–until proven otherwise–that Lyman et al are not hired guns of the denier lobby, but scientists who are studying the Earth system using the available data (warts and all), reporting their resutls honestly and trying to assess their significance.

  4. 54
    Steve Sadlov says:

    RE: #51 – Dano, you once again missed the point. Density of human population. It’s very straight forward. The less straightforward part is the transform. For so called “1st world” countries the transform approaches a certain set of characteristics and for the least developed ones another certain set is approached. Then the continuum between the two. But still, I believe a good approximation could be done. Pielke Sr. appears to be on the right track with his notion of various types of anthropogenic forcing.

  5. 55
    Jim Dukelow says:

    Re Comment #37

    A potentially ad feminam comment with some relevance to the mini-thread on Industrial Spam.

    The content and English-is-not-my-native-language flavor of Comment 37 suggest that Sonja Christiansen might be the same person as Sonja Boehmer-Christiansen, a Reader in Sociology at the University of Hull in the UK. Sonja.B-C was a regular contributor to the Climate Sceptics Internet mailing list in the early 2000s. Although having no educational background in the physical sciences, she had decided that the proponents of anthropogenic global warming were wrong and the sceptics were right and devoted herself to providing spurious sociological explanations for why the proponents were such bad people. She was the editor of the non-, or sub-, or quasi-peer-reviewed journal Energy and Environment, and offered her journal as a forum for the “sceptics” on the list to get their message out. More than coincidentally, Energy and Environment published both the piece-of-trash white paper by Soon, Baliunas, Robinson, and Robinson that Frederick Seitz had formatted to look like a PNAS paper and was peddling to several thousand of his dearest friends AND the first McKitrick and McIntyre hockey-stick hit piece. Uniquely in my experience with climate issues, Sonja.B-C is a left-wing “climate sceptic”.

    Of course, there are lots of Christiansens in the world and probably more than a few Sonja Christiansens, so the Sonja Christiansen of Comment 37 may be a completely different person.

    On a more substantive note, Sonja Christiansen wrote:

    “The idea of humans changing climate is by no means new and has been used for political purposes for centuries, if not longer. Just another version of the politics of fear, note it is always the future that will be worse, diverting attention from present problems.”

    This appears to assert that human society has never affected climate, and assertion for which there is a fair amount of contrary evidence. Consider the deforestation accompanying human settlement around the Mediterranean and elsewhere and the dispersal of agricultural societies to the ends of the earth from centers of agricultural innovation in the Middle East, China, and Meso-America.” Back in the late 1800s, the same sorts of economic interests now fighting understanding of climate change were trying to sell land in the Western Great Plains and would tell prospective land buyers that “rain follows the plow”. Their campaign destroyed John Wesley Powell’s sensible program for settlement and agricultural development in the arid West, with consequences that haunt us to this day. This time the stakes are much bigger.

    Best regards.

    Jim Dukelow

  6. 56
    SecularAnimist says:

    Another followup to Jim Redden who wrote in #14: “what solutions will be ultimately proposed, and the actual effectiveness, holds my keen interest.”

    The US Public Interest Research Group published a report today entitled “Rising to the Challenge: Six Steps to Cut Global Warming Pollution in the United States” in which they lay out a six-point plan by which the USA “can reduce its global warming emissions by as much as 19 percent by 2020 by taking a set of aggressive but achievable steps toward improved energy efficiency and increased use of renewable energy, within the context of mandatory limits on global warming pollution.”

    Technical solutions exist and are ready to be implemented. What’s needed is the political will to implement them. The importance of shifts in public opinion such as indicated by this poll is that it suggests that the necessary political will may be coming into existence.

  7. 57
    Dano says:

    RE 54 (Sadlov):

    Thank you Steve. I refer you to our previous discussion on how your assertion about my missing the point is erroneous.

    Nonetheless, lest we waste too much bandwidth on nits, perhaps you have a ref that does the density function with the GHCN record, and shows the bias you seem to be arguing for? Did not the initial stab at this idea say something different than your density f assertion, or do you have data you collected that say something different than Imhoff?

    Or perhaps you are preparing a manuscript for the ‘approximation’ you mention above? Will it appear in the first issue of Galileo?



  8. 58
    Margie says:

    I find it extraordinary that intelligent educated people are not aware that Katrina was both a hurricane and a disaster, and apparently have not looked beyond mainstream media coverage, which was almost exclusively of NOLA, to comprehend the extent of the coastline destroyed by Katrina’s surge. It is in fact the largest natural disaster this country has experienced, and that is true even if talking about the disaster areas that do not include NOLA. Since no one seems to know basic geography anymore I feel obliged to point out before going any further that NOLA is not on the coast, and when I talk about a disaster along the coast, I’m by definition not talking about NOLA. It is precisely in support of what people along the Gulf Coast call the “invisible coastline” that I am in the process of documenting the extent and severity of the surge this month, albeit in a fairly casual non-technical manner, but as best I can. I have spent this past year trying to figure out how I could find a forum to bring public awareness to the disaster, before the one year aniversary approached, of the miles and miles of coastline that were obliterated by the record surge, which surpassed all historical measurements for the northern Gulf Coast region.

    However, even though NOLA did not get the brunt of the hurricane, and even though the canal failures were exacerbated by design flaws and lack of ongoing maintenance, and so it was these canal failures that caused so much of the damage in that city, and not the direct effects of the hurricane, I cannot in my heart feel anything but sympathy and compassion for the people of NOLA. I certainly don’t understand snarky comments meant to imply that NOLA’s suffering was no more than they deserved for not putting money into maintaining an adequate levee system. Although the shortcomings were those of local government, it was ordinary people who suffered as a result.

    Also, not all the damage in NOLA was caused by levee failures. Some damage was caused directly by the hurricane. I know of a home that was destroyed because wind blew off part of the roof, rain came in, and because they couldn’t return for some time, mold destroyed everything in that home. So I have no problem with understanding NOLA’s damage as being the result of a hurricane: a natural disaster. But I’d be a lot happier if every person in the US understood that NOLA was only a very small part of the actual area affected by this natural diaster. How is it possible to put this into perspective? Katrina affected two-thirds of the entire state of Mississippi, and that is just one state out of several that were affected. Mississippi had to remove over 40 million cubic yards of debris, after the storm. Twenty-five million of that was directly along the coast. They did it in record time: ten months.

    The area of coastline that was affected by Katrina was about the same distance as the coast between, say, Baltimore and New York City. I’m curious to know, now that I’ve made you aware that miles of populated coastline and dozens of communities were either totally or partially destroyed, if your lack of compassion for NOLA extends to the people of the Louisiana, Mississippi, and Alabama Gulf Coast as well. Is there some specific number of people that have to die before you consider it a bona-fide disaster? Some minimum average income for the area? Perhaps some sections of the country “count” and others don’t? Some communities are important, others are not? Shame on you, regardless of whether your attitude comes from ignorance or prejudice.

  9. 59
    pat neuman says:

    re: 52


    These link might help in answering your question: ‘What is going on at NOAA?’

    NOAA Leadership

    NWS Headquarters Organization and Structure

  10. 60
    Chris Rijk says:

    A Europe-wide study on the arrival of spring (it’s coming earlier):

    Press release:

  11. 61

    Here’s why the Sun can’t be doing it.

    The emission temperature of a planet, the temperature as measured from some distance away, can be found with this equation:

    Te = (S (1 – A) / (4 sigma)) ^ 0.25

    where Te is in kelvins, S is the Solar constant, A the Earth’s bolometric Bond albedo, and sigma the Stefan-Boltzmann constant. S at Earth’s orbit averages 1367.6 Watts per square meter, the Earth’s albedo is about 0.3 (assume this is exact for the moment), and sigma has the value 5.6704 x 10^-8 in the SI, which gives an emission temperature for Earth of 254.9 K.

    Global warming since 1880 or so has been about 0.6 K. How much would the Solar constant have to have risen to provide that much of an increase? Solving for S, we have

    S = 4 sigma Te^4 / (1 – A)

    Plugging our results for Te back into this equation, it gives S = 1367.9 (which shows the problems of using significant digits). If we take Te = 254.9 – 0.6 = 254.3, we get S = 1355.1. In other words, the Solar constant would have to have increased by 12.8 Watts per square meter to get the observed warming. The Solar constant has, in fact, risen by about 1 Watt per square meter over this time period. Solar can’t do it alone without violating conservation of energy.

    Now, there may be some feedback in the Earth system that “multiplies” changes in the Solar constant. But until the Solar freaks identify what that feedback is, their theory fails on basic scientific grounds.


  12. 62
    Hank Roberts says:

    Abstracts, online early, from the journal Global Change Biology that reported the study on early spring (and late fall) that Chris refers to above.

    This is I think what convinces people — when everything you look at shows a small change and almost all the changes are in the same direction, you don’t think “random” you think it’s an effect.

    This is an amazing collection of abstracts well worth some serious attention by the climatologists — as in, please, folks, read and discuss:

  13. 63
    Russ Hayley says:

    It really surprises me that Realclimate has mentioned a poll on Global Warming. On a site that supposedly seems to pride itself on the apolitical side of the the issue, why would the admin be bothered about a poll? It seems it could be in danger of dragging itself into the political wrangling over climate change and have the ‘misinformation mud’ accusation slapped over it.

    [Response: It was just a post pointing out some interesting results on how people in the US think about this issue. We’ll be back to the science soon! – gavin]

  14. 64
    Eachran says:

    Dear Gavin, dont apologise please for including a poll result in your excellent material. I am sure that people who read the posts on this site know a cause from an effect and an alarmist from a denier.

    As for science I recall one of the group, I think it was Raypierre, writing about accessibilty not so long ago. Quite so.

    Dont weaken.

  15. 65
    Wacki says:

    Re: 63 Russ Hayley

    It really surprises me that Realclimate has mentioned a poll on Global Warming. On a site that supposedly seems to pride itself on the apolitical side of the the issue, why would the admin be bothered about a poll? It seems it could be in danger of dragging itself into the political wrangling over climate change and have the ‘misinformation mud’ accusation slapped over it.

    This poll reflects how well the general public understands the science of climate change. Do you think a first grade science quiz is political? What about the teacher perfomance evaluations? There isn’t a whole lot of difference between those two and this poll.

  16. 66
    Eli Rabett says:

    A good first order surface measure of population density can be seen here.

    As to the general discussion, one should NEVER start a conversation on Katrina/heat wave/anthropic global climate change by saying “one can never attribute any single event such as Katrina/heat wave/etc. to anthropic global climate change. Some useful responses have been suggested above. I prefer “on average” followed by a pause.

    There are two reasons for this. First, if you are talking with a denialist, the burden is shifted back to him or her to make the attribtuion argument. If you start by making the denialists argument, you might as well grab another beer and go sit in the corner. Second, the answer “on average” might be sufficient for someone with a cursory interest, or who knows a bit, and it provides a platform on which you can build.

    In building your answer, NEVER say that you CANNOT attribute Katrina, etc. to anthropic global climate change. State your argument in a positive way, such as we know that man made climate change is warming the oceans and the seas. We know that warmer sea temperatures make for more intense hurricanes, so when we see a string of very intense hurricanes in very warm seas, where the temperature of the seas is what we expect from anthropic global climate change, why yes, we are very suspicious that some of this disaster was caused by man made climate change.

    BTW, that answer was much too wordy, but I hope the idea gets through.

  17. 67
    Dano says:

    IMHO, taking Eli’s comment (now 66) and Hank’s (again) excellent links in [now 62] together, it should be simple enough to enjoy a decent conversation regarding global change. (BTW, the paper that utilizes Eli’s foto also has close-ups that are fascinating as well).

    After all, it is not just climate that is changing, but plants and birds too. Everyone can see that, every day, they have plants and birds in their backyards, but not everyone can see that every day they have climate in their backyard (scalar perception problem).



  18. 68
    Joseph O'Sullivan says:

    About the last paragraph of the post, how scientists might be more effective by focusing their efforts to explain the climate science to those (journalists, policy-makers) who set the dominant themes, I would say yes and no.

    Yes, conducting scientific research and communicating complex ideas to the general public are two different jobs that require different skill sets. So at times it would be better for the scientific community to communicate to the public through people who have more experience in public relations.

    No, maybe not for the general public, but for the interested public it is very helpful to be able to hear what the scientific community is saying, directly from the scientists. I think blogs like RealClimate are invaluable for this. If someone wants to find out more than just a short news item, there should be a source they could go to for more in-depth coverage.

    As far as why a science blog would do a post about a public-opinion poll, I’m pretty sure the scientists want to know if their efforts to educate the public are working!

  19. 69
    Dan Hughes says:

    #65 “This poll reflects how well the general public understands the science of climate change.”

    No it does not because it cannot. The results of the poll reflect what some of the general public have heard/read/studied (in order of likehood) about climate change. A public opinion poll cannot be used to determine how well any science is understood.

    #67 “Everyone can see that, every day, they have plants and birds in their backyards, but not everyone can see that every day they have climate in their backyard (scalar perception problem).”

    Nope, what people see every day in their back yard is weather, not climate. And they would need to keep detailed records over a 30 year period to attempt to ferret out the effects of climate. Plus, a single back yard is far from sufficient spatial scale to actually observe climate. Unless of course, the back yard in question just happened to be at a boundary or margin for the flora and fauna and plants and birds which occupy said yard and the changes in the temporal and spatial ranges of these could be observed. Well, maybe over 30 years one could determine some temporal aspects of climate in a yard.

    [Response: Actually, this statement is wrong, and it exposes a common misconception worth correcting here. An obvious counter-example is the seasonal cycle which itself can be considered a ‘climate’ signal (that is, a systematic shift in the statistics of daily weather variables), and one which has a highly predictable and easily perceived influence on daily weather statistics. But more subtle examples are the interannual variability associated with the El Nino/Southern Oscillation and North Atlantic Oscillation phenomena, which are certainly climate phenomena. In the case of the NAO, for example, in an article in Science from 2001, Thompson and Wallace established that a negative phase NAO winter is associated on average with a tripling (Orlando, Florida) to nearly tenfold (Paris, France) increase in the incidence of cold winter temperature extremes relative to normal, over the course of a season. This is easily perceptible in day-to-day experience. Other examples abound. – mike]

  20. 70
    Steve Sadlov says:

    RE: #60 – I thought I’d pull just one thing out of the press release: “Their research also reveals a definite contrast with Spring arriving later in countries such as Slovakia, that have had recent decreases in temperature.”

    I have many questions about other aspects this study.

  21. 71
    Steve Sadlov says:

    RE: “Unless of course, the back yard in question just happened to be at a boundary or margin for the flora and fauna and plants and birds which occupy said yard and the changes in the temporal and spatial ranges of these could be observed.”

    Funny you mentioned that. Our place is at such a boundary, between the typical “foothill” biome below 1000 feet and the typical “coastal highland” one above it, on the lee side of one of the Coastal Ranges. Simply put, below us is open coast live oak forest and savanna and above mixed evergreen forest. A few notable things over about a 15 year time frame. Firstly, within the “foothill” area the oaks are expanding. Secondly, more “highland” species such as Steller Jays and newts are showing up. Generally, the overall assemblage seems to reflect some sort of push into a slightly cooler and wetter regime, over the long haul.

  22. 72
    Dano says:

    RE current 69 response (to Hughes):

    Thank you for the help Mike.

    Gardeners and birders often can indeed perceive climate in their backyards, and often – because of their familiarity with the seasons – can better relate observed phenomena to larger-scale phenomena. Gardeners notice earlier springs or droughty conditions because of the effect on their plants (and many keep records). Birders document the earlier return of migratory birds to the area because they watch which birds frequent their feeders and when (and many keep records).

    This information is among the many, many indicators present in the global change literature that Hank linked to above [BTW, thanks again Hank – I just noticed one of my undergrad advisors is a co-auth on one of the papers].

    That is: there is ample evidence for global change and it is not dependent upon certain totems named after winter sports devices.



  23. 73
    Lynn Vincentnathan says:

    I’ve always figured lay people would flip quickly from under-attributing effects to GW to over-attributing, once they accepted GW was happening.

    However, another way of looking at it is the environmentalist/precautionary view that some “people living in the world” might hold. That would be opposite science, and would be what I call the “medical model.” Since we know pretty well AGW is happening, then we could attribute all effects to it (that are supported at least somewhat in theory — maybe even throw in earthquakes, at least those near glacier melt regions) — and let others disprove that AGW had absolutely no causal impact on, say, Katrina whatsoever at 95% certainty…or 99% certainty…or (the denialist standard) 101% certainty.

    But it’d be a moot point even if they could prove beyond a shadow of a doubt that AGW had absolutely no impact on Katrina, since I’d still go on reducing my GHGs & saving money anyway!

  24. 74
    Lynn Vincentnathan says:

    Guess there’s still a lot of room for doubt about human-caused GW, as a recent Salt Lake Tribune story goes :( : “A new study published in the influential journal Nature reveals the Arctic had a tropical climate 55 million years ago, further adding to doubts that climate fluctuations are due to human activities.”

    Yep, blame it all on nasty nature…sure makes us feel good as we head into mega-Katrinas, etc. And we don’t even have to turn off lights not it use.

  25. 75
    Dan Hughes says:

    Yes, records over many years and over significant spatial scale define climate. Day-at-a-time-in-a-backyard does not define climate. Steve must have a big backyard.

  26. 76
    Bryan Sralla says:

    Re: #69 (Moderator Response) Mike, what is your feeling about climate changes along western North America (high latitudes) and phase shifts in the PDO? In some recent personal coorespondence with the Alaska Climate Research Center, they indicated that the current 2006 cooling trend (Fairbanks -2 F from 30 year climatological mean through first seven months of 2006) in Alaska may be associated with a phase shift in the PDO. How do these regional observations line up with your understanding of the PDO?

  27. 77
    Wacki says:

    Re 69: No it does not because it cannot. The results of the poll reflect what some of the general public have heard/read/studied (in order of likehood) about climate change. A public opinion poll cannot be used to determine how well any science is understood.

    I used the *first grade* qualifier. I really don’t think there’s a whole lot of difference between getting the questions in this lesson plan right:

    and a public opinion poll on climate change right. I still think public polls is a *somewhat* reasonable way of measuring the combined effectiveness of things like, press releases, etc. Bleh arguing about this is pointless.

  28. 78
    Hank Roberts says:

    The definition biologically for “Spring” and “Fall” isn’t the equinoxes — they’re describing behavior; pupation, emergence, arrival, departure, flowering. You have to look at each study — each species — and pay attention to which use day length, which use temperature, which use cues second hand from other plants or animals that are seasonal. The point is that so many studies over such a large area shows sudden changes, and that ecologies are built from coevolution including timing.

    Where the caterpillars’ timing is more advanced, and they have turned to butterflies before a bird species’ fledgelings are hatched, the caterpillars won’t serve as a food source.

    And then the farmers will notice a plague of caterpillars, perhaps.

  29. 79
    jre says:

    Re/ #74: Lynn was right to be wary of the Salt Lake Tribune piece. It is not actually a story, but an op-ed by David Ridenour, who has been paid handsomely for some years now to place anti-Kyoto press releases wherever they will be most visible. It is, to put it bluntly, disinformation.

  30. 80
    Dano says:

    RE 79 (jre):

    Indeed. That particular facet of the campaign was launched some days ago and is gathering steam.

    Caveat: even on filtered news compilers like ClimArk, one must be critical and careful of what one reads (hence the value for some of he said-she said articles) – viewing the bio of the author may help (as it provides a clue in this case).



  31. 81
    Dean's World says:


    In sort of but not really related news, the RealClimate folks display their usual int…

  32. 82
    Eli Rabett says:

    There is a good example of what I was warning about in #66 on Andrew Dessler’s blog in the comments, starting with a comment from George Landis, definately on the denialist side”:

    “George Landis said…
    Oh, Oh, let me bill f.
    From Kerry Emanuel’s [MIT] homepage:
    “Q: I gather from this last discussion that it would be absurd to attribute the Katrina disaster to global warming?
    A: Yes, it would be absurd.”

    Quoting from the interview in detail is no help after that although Emanuel says all of the things that have been repeated here.

    So again, I will admonish folk NEVER to answer the way Kerry Emanuel did. Answer in the positive: On average yes, or there is good reason to believe that it exacerbated the situation, etc.

  33. 83
    Bob Lane says:

    You write: “This begs the question …” No, it RAISES the question! Begging the question is the name of an informal fallacy in logic. Come on!

  34. 84
    Eric E says:

    In response to your question on how I could have based skepticism on ocean carbon uptake – I was an oceanography master’s student at the time, so certainly I had gaps in my knowledge at that time. And you are right that my skepticism was about whether warming was anthropogenic and not source of carbon. The issue as it appeared to me then was: we knew that some 40% of our emissions are coming out of the atmophere, but we didn’t know where they are going, and part of that was whether the ocean was a source or sink. Right or wrong, I interpreted that as an indication of vast error bars on physical mechanisms that precluded distinguishing natural variability from anthropogenic warming. Since then, however many other measurements have been made (and/or I have become aware of them) which confirm climate sensitivity and require anthropogenic warming to explain. My point was really just to illustrate how measurements like that have to percolate through various kinds of people. Hope that makes more sense.

  35. 85
    Jan Lindström says:


    Surely this equation apply on visible and perhaps IR? Recent research shows that the high energy cascades from the sun creates clouds in the atmosphere. Albedo is affected by aerosols which in turn are of 99% natural origin (such as forrests etc). However, there are still 1000 reasons why we should stop using fossile fuel, even if the natural variations are shown to be of a much greater magnitude than previously expected.
    Can any one explain how the Urban Heat Island effect is accounted for in he temperature readings? According to some recent theses and articles it can be signifikant, sometimes a couple of degrees more than a presumed average. Why is not very remote stations used as a reference instead, if there is a discussion about the magnitude of the UHI?

  36. 86
    Eli Rabett says:

    Re #85: For the GISS surface temperature record see

    From the abstract:
    (3) a more flexible urban adjustment than that employed by Hansen et al. [1999], including reliance on only unlit stations in the United States and rural stations in the rest of the world for determining long-term trends. We find evidence of local human effects (“urban warming”) even in suburban and small-town surface air temperature records, but the effect is modest in magnitude and conceivably could be an artifact of inhomogeneities in the station records. We suggest further studies, including more complete satellite night light analyses, which may clarify the potential urban effect.

    but read the entire paper for the nitty gritty details (there is an Acrobat file you can download). You can also find less technical discussions here and there

  37. 87
    Jim Dukelow says:

    Re #85 and #86

    A few years ago (Nov 2001) I investigated the impact of UHI by using the Idso’s nice temperature database GUI (free at that time) to compare average temperature trends for 1979 to mid-2001 for the Jones et al. and MSU temperatures for some of the world’s “empty places”, places on the map where there are few nighttime lights.

    Location, MSU (deg C/dec.), Jones et al. (deg C/dec.)

    N. Quebec & W. Labrador, 0.31669, 0.32748
    N. Ontario & James Bay, 0.41266, 0.53266
    N. Alberta/Sask./Manitoba, 0.4238, 0.47048
    E. Yukon & Nunavut, 0.10099, 0.66523
    Alaska (N. of Fairbanks), 0.19095, -0.00815
    SW Alaska, 0.1955, -0.01285
    Arabian Peninsula, 0.02097, 0.32769
    Sahara, 0.1045, 0.34583
    W. China and W. Mongolia, 0.33462, 0.3284
    the Outback, 0.00745, -0.05663
    Amazon Basin, -0.18314, 0.17134
    Patagonia, -0.01297, 0.04853

    The correlation coefficient for the 12 MSU/Jones data pairs is 0.42645, which is not significantly different from zero, using the standard Fisher-z transformation to construct a 95% CI for r = (-0.19524, 0.8737).

    What is striking in this data is the general strong warming, particularly in the northern high latitudes and the general agreement between MSU lower tropospheric average temperatures and the Jones et al. surface temperatures.

    It would be interesting to see the same comparison using the current Spencer and Christy anomaly data, which has changed substantially from the 2001 version.

    A lot of the concern about UHI would go away if the surface data set compilers would generate a Voronoi tesselation of the surface and do an area-weighted average of urban and non-urban stations. This would have the effect of increasing the weight of non-urban stations in the average.

    Best regards.

    Jim Dukelow

  38. 88

    #87, Jim, really appreciate this info. The Yukon and Nunavut trend is particularly stronger than with MSU, any reason for this difference? In fact since 2001 I suspect that this rate is even greater for remote locations.

  39. 89
    Jan Lindstrom says:

    Thanks to Jim Dukelow and Eli Rabett (86 and 87)

    “Urban heat islands occur mainly at night and are reduced in windy conditions. Here we show that, globally, temperatures over land have risen as much on windy nights as on calm nights, indicating that the observed overall warming is not a consequence of urban development.

    The reasoning behind this is that the major cause of urban heat islands is the reduced cooling that occurs at night when the “view to space” of the surface is blocked by buildings. In more rural areas, cooling can be stronger. This is more likely to occur in calm conditions, when air near the surface is less well mixed with air higher up. Since the UHI effect is reduced in windy conditions, if the UHI effect was a significant component of the temperature record, then we would see a different rate of warming when observations are stratified by calm or windy conditions. The absence of such an effect (which is what Parker finds) is, conversely, evidence of a minimal UHI effect on the record.”

    I´ve read articles showing that an important UHI factor is aerosols (pollutants) and the absorbance of surfaces. There must also be a substantial emission of heat from the buildings themselves not coming from the warming up by the sun. I also think that the effect of boundary layers could well extend trends very far from the urban areas. Turning everything round. What if the boundary layer whe are studying are “contaminated” of a magnitude so that they will not be affected as much by the wind as expected. At least european cities are built to withstand wind influences on the climate, preventing it to reach the surface by narrow streets etc. A work from Uppsala, Sweden shows that the mean temperature deviation from two meauring sites in the city, can vary between 0.28 (min) (season, windy and clear) up to 0.48 (max)(season, cloudy and calm) on annual basis. Assuming these results can be moved to be valid for other cities, does not that mean that assuming max 0.05 from UHI is an underestimation?

    The work can be found here (in english as well)

    Is still think that the reasoning behind the omitting of the UHI is a bit over simplified. I have done some research on so called micro-meteorology. This could apply to cities. I think the whole issue is very complex and needs much more attention before we really can say the warming trend is global as opposed to an integration of heat islands effects. Just taking a quick look at a map showing the different temperature trends globally I can not help asking the question; why are in broad terms, the warming trends so strongly correlated to urbanised areas and the cooling trends to remote locations.

    Back to the sun.

    I have seen only one article going through the suns influences not only studying the visible and IR-part of the spectrum after all the sun is emitting a lot more energy than that so why not at least trying to calculate the energy imparted throughout the whole electromagnetic spectrum? Also, what effect has the variations in the magnetic field from the sun? It must have an influence on temperature, but how large is it?


    There are articles showing that aerosols can due to their surface properties sometimes contribute to warming. This makes it more complex in the modelling work. But another factor pussles me, how is the aerosols accounted for when they finally have been deposited to the surface? Surely, they will affect albedo on glaciers for example. Since the aerosols mainly have absorbing qualities (regarding visible light and IR) could not the retraction of glaciers be attributed to such an effect rather then a temperature rise? Has anyone looked into that? It is known that aerosols can travel a long way. I was myself a part of a study looking at the emission of aersols in UK deposited in Scandinavia. We found that when the aerosols drops and travels near the water surface (North Sea) a boundary layer about the 2-100 meters above the maximum wave heights worked as a non-friction ice! I.e the particles are thought to drop into the sea but they may travel long distances before actually depositing. I´d guess the glaciers and other snow and ice -areas are full of particles changing the light and heat absorbing properties to a measurable degree? Does anyone agree?

  40. 90
    Jan Lindstrom says:

    Regarding my question if there is an article on energy consumption rate vs. temperature, there is one and they found a striking connection to the registered temperature trends! – engelska

    If what they show is true, could there actually be a substantial UHI-effect where the weighting factor of the city area is far too low? If this in turn is true then, on average, we should not see any warming trend in the oceans? According to a recent article there is actually a cooling trend right now (see below), however, for an extended period there is still a warming trend contradicting my suggestions above.

    “Recent Cooling of the Upper Ocean
    John M. Lyman1,2,3, Josh K. Willis4, and Gregory C. Johnson1
    Submitted 26 May 2006
    Geophysical Research Letters
    Accepted 31 July 2006
    Abstract. We observe a net loss of 3.2 (± 1.1) x 10^22 J of heat from the upper ocean
    between 2003 and 2005. Using a broad array of in situ ocean measurements, we present annual estimates of global upper-ocean heat content anomaly from 1993 through 2005. Including the recent downturn, the average warming rate for the entire 13-year period is 0.33 ± 0.23 W/m2 (per unit area of the Earth’s surface). A new estimate of sampling error in the heat content record suggests that both the recent and previous global cooling events are significant and unlikely to be artifacts of inadequate ocean sampling.”

  41. 91
    Eli Rabett says:

    (Re #90) Jan, it is important to remember that what is measured is a temperature anomaly (difference to a base period) at locations, not a temperature. So what counts is not the absolute temperature (which is higher in urban areas), but how that changes over time at each location.

  42. 92
    Hank Roberts says:

    Good article here on California Sierra Nevada mountain studies:

  43. 93
    Dano says:

    RE 92 (Roberts):

    I continue to enjoy your links Hank. Compare the discussion in that article with a discussion about Andean glaciers on a different type of climate website.



  44. 94
    Jim Dukelow says:

    Re #90

    Well, I read the Nigro et al. paper that Jan pointed us to and it strikes me a being some sort of joke. The authors confect a transient heat transfer equation

    c_eff*(dT/dt) = CapPhi + Delta_Phi + little_phi – k*T^4

    where CapPhi is solar flux at surface, Delta_Phi is solar cycle variation in solar flux at surface, little_phi is human energy consumption, T is surface temperature in K, and

    c_eff = 4*10^22 J/K is the global heat transfer coefficient.

    The authors claim that the value of c_eff “suggests” a value 3.5 +/- 2 meters of the earth’s surface that is “involved in the warming process”. This effective depth might make sense were not 70% of the Earth’s surface ocean, which will act very differently in absorbing heat than solid earth. The temperature T on the left hsnd side is the surface temperature, but the temperature on the right hand side (controlling the loss of heat from the system) ought to be the temperature at some point high in the atmosphere.

    CapPhi is roughly three orders of magnitude bigger than Delta_Phi, which is probably two or three orders of magnitude larger than little_phi. Finally, little_phi is a reasonable proxy for anthropogenic carbon dioxide, methane, and nitrogen oxide emissions, which really do have an impact of global temperatures, unlike the simple conversion of fossil fuels to thermal energy.

    If you look at Figure 1, it doesn’t really support the authors assertions in the text.

    The whole thing is just silly.

    Best regards.

    Jim Dukelow

  45. 95
    ike solem says:

    Re#59, hi pat,

    That does help explain things.

    Last week’s issue of Science contained an article relating to Western US hydrology and increases in wildfires that you might find interesting:

    I haven’t looked over it yet, but I think it will be interesting to read the article and then review some of your prior posts on the topic of hydrology. More feedforward carbon effects, seems to be the gist.

  46. 96

    re #95


    Thanks for the link to climate change, fires and hydrology out West. Many people understand that hydrologic change is part of climate change, except NOAA’s NWS meteorologists who remain skeptical that climate change is happening.

    I’d like to know more about how fossilized leaves from bean plants were found in the Big Horns which Scott Wing said had migrated 1,000 miles north from the latitude of Louisiana to escape the heat which preceded the Paleocene Eocene Thermal Maximum (PETM) 55 mya. I wonder how he reached the conclusion that the plants were escaping heat in the South preceding the PETM? I think drought, fire and the rising sea had a large role in the migration. I posted a similar comment (#38 of the entry by Eric Steig called Is Antarctic climate changing?). I have an impression that Eric Steig dislikes many of the posts which I’ve made since RC began in 2004. but I don’t know why. Anyway, that’s the reason for making a comment similar to #38 below the entry on Antarctica. In #38 of the entry on Antarctic, I questioned what polar amplification means for areas in the South and Upper Midwest (where average Jul-Aug daily minimum temperatures are increasing). I posed the question to Eric Swanson, who seems to me like he’s a well respected climate scientist by his comments and the comments which Eric Steig made recently. I don’t know much about you but you also seem to be a well respected scientist (by the nature of your comments and those of others at RC).

    It must be rewarding to earn that type of respect. I wouldn’t know, not having earned any genuine respect from other scientists lately. I can blame myself in part for that. I also blame arrogance I’ve seen from NWS supervisors and staff. Meteorologists are arrogant as a result of having studied the atmosphere and having gained operational experience making weather predictions which they say save lives and property, although other factors are no doubt involved which make a person seem arrogant. I’ve been told I came across as arrogant for spring runoff outlook inter-agency meetings held at the Corps of Engineers in St. Paul and the NWS North Central River Forecast Center in Chanhassen, MN. That surprised me when I learned that. In trying to appear confident when giving the spring flood outlooks, instead it seems that others got the impression that I was arrogant, not confident of my work. Oh well, I need to forget about all that now and get back to prairie gardening for wildlife, and being a better husband, which is much more rewarding and less stressful than working for NWS in hydrologic modeling and forecasting (29 years and 5 months).

  47. 97
    Jennifer says:

    I didn’t read all the comments, I hope I’m not repeating anyone. I don’t want to discount the effect of the media — but (anecdotally) I often hear people talk about “when I was a kid.” My mother-in-law for example used to ice skate on ponds which haven’t frozen in over 20 years. When she starts saying things like this, everyone around chimes in with his or her own experience… So I think people’s experience with the weather over decades (and not just recent severe weather events, as you mention) leads them to believe in global warming.

  48. 98
    Pat Neuman says:

    The people in the US are responsible for the majority of anthropogenic carbon now present in the atmosphere and oceans. The discussions at realclimate have been unsuccessful in changing public perception on global warming enough to result in meaningful reductions in US greenhouse gas emissions to date. Although several dozen posts at rc since Nov 2004 have identified the main reason* for the failure in changing public perception on global warming, the rc scientists have ignored the reason and those commenting at rc have ignored and ridiculed the reason given.

    * reason – The National Weather Service has failed in it’s responsibility to help educate the people on climate change which is shown in the article linked below titled: ‘Arrogant meteorologists are downplaying global warming’


  49. 99
    Rod Brick says:

    RE #63: a poll tells us the depth of knowledge of the people polled??? Wacki, you must be wacky. (I’m so sorry; I hate ad hominems but the pun was just irresistible…)

  50. 100
    Rod Brick says:

    re #56 and Secular Animist. Using the USPIRG for technical and economic justification is really a stretch. I admire and respect the people at USPIRG (even though I, being a crabby conservative, disagree with most of their contentions and assumptions) but for what they are: political activists. Scientists and economists they ain’t.