Who writes Rodney’s rubbish?

rodenymorph.gifWho’s this supporting the NZ C”S”C’s idiotic attempt to cast doubt on the NZ temperature record? Why, it’s none other than Rodney Hide, leader of the ACT Party, and Minister of Local Government, Associate Minister of Commerce, Minister of Regulatory Reform and Parliamentary principal climate crank. Hide has written to climate change minister Nick Smith, demanding that the NIWA release the temperature data:

There is only one process that is appropriate for matters of science, and that is to release all data, together with a detailed account of what adjustments have been made, with an account of the reasons for doing so, and the computer codes that have been used to adjust and smooth the final published series, together with details of which measurements have been discarded. All the data and the relevant computer codes should be available for scientific scrutiny.

Free the NIWA code! What a rallying cry. It’s a pity that he thinks the likes of Treadgold constitute independent scientific scrutiny. Hide’s also been taking instructions on the CRU hack, and is seemingly happy to completely misrepresent what’s been going on. Apparently the emails:

…reveal a systematic attempt to manipulate the historical time series data, together with what appear to be arbitrary adjustments to the computer codes which produce the averaged and smoothed temperature data…

Er, no. That’s not true. The Herald does a far better job than the Minister of Local Government of covering the stolen emails and what they actually say. But perhaps Rodney gets his “facts” from somewhere else. So, in the spirit of his letter to Nick, here’s mine to Rodney.

Dear Mr Hide,

In your letter to Nick Smith, dated November 27th, you refer to a NZ Climate “Science” Coalition document entitled Are we feeling warmer yet? and use it as the basis for the request of further information from NIWA. In the interests of open government, and the full disclosure of the interests of Ministers of the Crown seeking to use to use their position to advance the agendas of external organisations, I request that you answer the following questions in full, revealing any email or other communications made in relation to this subject during the period in question.

  • Who drew your attention the NZ CSC document?
  • Have you actually read to it?
  • As an “environmental scientist“, who understands (per your letter) that adjustments to temperature series are necessary, did you not notice that the NZ CSC document deliberately ignored the adjustments in order to make their case?
  • If you did not, why not?
  • Who drafted your letter to the Minister for Climate Change Issues?
  • What correspondence, via email, letter or other means (including telephone conversations), have you had with Bryan Leyland, Alan Gibb, Terry Dunleavy, Bob Dedekind, Owen McShane, Richard Treadgold, or any member of the NZ Climate “Science” Coalition, in respect of NIWA temperature data, the theft of emails from the Climatic Research Unit at the University of East Anglia, or climate science or policy matters in the last month?
  • As a Minister of the Crown, do you support the theft of emails and data from universities here or overseas?
  • If not, why do you use stolen emails to support your case?
  • If you have not read those emails, who supplied your interpretation of them?
  • Do you think its reasonable for a Minister of the Crown to join a smear campaign against New Zealand scientists?

Thank you for you urgent attention to these matters. I look forward to receiving a full disclosure of all and any information relating to this issue at your earliest convenience.


Gareth Renowden

(But I won’t be holding my breath…)

50 thoughts on “Who writes Rodney’s rubbish?”

  1. “There is only one process that is appropriate for matters of science, and that is to release all data, together with a detailed account of what adjustments have been made, with an account of the reasons for doing so, and the computer codes that have been used to adjust and smooth the final published series, together with details of which measurements have been discarded. All the data and the relevant computer codes should be available for scientific scrutiny”

    … err whats the problem here Gareth?

    Note that others are also calling for exactly the same thing internationally,

    ““This whole concept of, ‘We’re the experts, trust us,’ has clearly gone by the wayside with these e-mails,” said Judith Curry, a climate scientist at Georgia Institute of Technology.

    She and other scientists are seeking more transparency in the way climate data is handled and in the methods used to analyze it.”


    1. … err whats the problem here Gareth?

      It’s a beat-up, R2. Rodney is just playing along with the crank idée du jour, most likely doing a favour for his mates in the NZ CSC. If he deigns to answer my questions, then we’ll find out.

      There is no secret about NIWA’s temperature data — just a bunch of allegations based on lies promulgated by fools.

      Do you support smearing scientists, based on falsehoods?

      You wanna side with the fools?

      1. I’m not siding with anybody. I don’t belong to a group. I don’t carry a card, I don’t attend meetings.

        I don’t see a conspiracy. I don’t think Judith Curry has gone to the dark side. The letter probably came from Rodney hide.

        What he is asking for is reasonable. There is still unknown information – I still do not know the reason for any of the adjustments apart from Wellington. This is important information to the public. I am surprised you are not interested yourself.

        And as Rodney says, the data they didn’t use is as important as the data they did use. What stations are available to NIWA that were not used in the set that gave the trend?

        As Rodney says, this data contributes to global data sets that are used in AR4 to assess the merit of AGW.

        This does not mean that I am siding with “these fools”. I am saddened you break every issue into sides. It is more constructive to evaluate issues on logic rather than some deep seeded hatred for certain individuals and perceived groups.

        1. As Rodney says, this data contributes to global data sets that are used in AR4 to assess the merit of AGW.

          NZ could be warming (or cooling) at 4ºC per decade and it would make bugger all difference to the global picture.

        2. Actually R2, you ARE siding with these fools. There are only two substantive “sides” to this debate – on one side the scientists are warning that all their research is saying that the world needs to urgently cut emissions of greenhouse gases to avoid large and irreversible changes to the world’s climate. On the other side people are saying “Nah, nothing too bad is going to happen, so we can keep burning fossil fuels as usual”. Sure there are many variations on that argument but essentially everything you have said boils down to either supporting that statement or trying to undermine the scientific predictions.

        3. NIWA data, here, free of charge (just register yourself):

          Method of adjustment explained:
          Rhoades & Salinger, 1993, “Adjustment of temperature and rainfall recors for site changes”, Int. J. Climatology, 13:899-913

          You might also want to look here:
          since citeSeerx is a great way to navigate around scientific publications.

          Since (even if they are too lazy to do the search that took me all of an hour to find these documents and data) the CSC were told of this directly, years ago, it is hard to come to any conclusion except malevolent intent in repeating their claims and pretense at ignorance of the underlying data.

  2. Yes, private emails show that scientists are human, too – what a surprise…

    That climate change deniers have gone hyperbolic over this only shows how weak their case against AGW is.

  3. I’m with R2 on this.
    Your suggested letter to Rodney is simply a diversion, similar to the infamous letter Plimer sent to Monbiot because he found Monbiot’s questions about his book too hard to answer. If you have confidence that NIWA’s methodology is above board, and I do, why wouldn’t you be urging them to be more open about it?
    The popular suggestion that providing more data to the likes of the NZCSC is just providing them with ammunition (the same excuse Phil Jones likes to use) is short sighted stupidity, stupid enough in my opinion to justify dismissal.
    The scientific method is based on openness, if AGW needs secrecy, it has become a religion.

    1. NASA GISS decided some time to make their data and methodology freely available. The moronic deniers couldn’t even understand it and not one suggested improvement has been made by the said morons.

      Has that stopped the deniers from circulating their nonsense?. Nope. NIWA have better things to do than deal with ignorant vexatious, time wasting deniers.

      1. I agree with DP. It appears CRU is going to release all its data subject to getting the appropriate releases from its data providers.

        The deniers will do nothing with the data. What some might do is a line by line critique of the computer coding, but it will be at the level of

        “oh this is clumsy coding I could do it better.” They will fail to point out that their suggested improvements, if they make any, don’t make a difference to the results.

    2. A diversion? No. I’m making a political point in a political debate. This is most assuredly not about science. A few points you should bear in mind:
      1: NIWA has already released the “raw”, unadjusted data. If they hadn’t, Treadgold wouldn’t have been able to do anything.
      2: Some of the information on station adjustments has already been provided, or is available in the peer-reviewed literature. The Dunedin record, for instance, was published years ago.
      3: Some station adjustments haven’t been published. NIWA may or may not wish to publish them at some point (but doing so in these cash-strapped times will mean not doing something useful).
      4: Asking for “the code” is just risible. Does he want a free copy of Excel handed out with every set of files?
      5: If you look at a set of long record stations that do not require adjustments (because they’ve never moved, for instance), then they show the same warming, confirming that the full record is pointing in the right direction. I understand that Jim Salinger is going to demonstrate this point soon…

      I repeat, this has nothing to do with science or openness.It’s purely a political sideshow designed to add to the denialist noise pre-Copenhagen. If anything is a “religion” then it seems to me to be the cranks that exhibit the classic signs. They have their holy books (Plimer), they cling stubbornly to their beliefs in the face of the overwhelming evidence, they even have places they can go to worship, where they can recite their catechism (“warming’s a hoax”, “it’s all a fraud”).

  4. Gareth, I agree with you, but one small point: asking for the code (for all that Rodney likely doesn’t understand what that means) isn’t that big a deal. The data analysis was probably done with a scriptable language, so if you really want to know what was done you need a look at the scripts. Of course it would probably take weeks to collate them into a form readable by someone unfamiliar with the project. I’m sure NIWA don’t have an account code for “wasting my time to give AGW denialists something they don’t actually want”.

    1. Best response I’ve heard to the “show us code” stuff is to have someone complain that they dont have Matlab or Abacus and that scientists should be coding only in freeware.

      On data sharing – this is actually a great deal more expensive than you think. We have issues sharing data between different science groups let alone with amateurs. Reasons? The associated metadata is inadequate and it opens up the possibility of data being used by a scientist that would be inappropriate given the data’s limitation which are not understood by a non-expert. Its very time-consuming (read expensive) creating this metadata and while in an ideal world it would be done for every data set, the real world of limited funding ensures that it often only happens when the data set acquires significance. This is an important issue in science and along with e-science initiatives, it is generating a lot of discussion.

  5. Gareth,

    I agree with you that the CSC paper was pretty shallow. And Rodney is, I think, often on the wrong track with his climate change policies.

    But, and it is an important but, that doesn’t mean it is OK to just refuse to provide information.

    On the temperature record, yes, the Wellington site correction makes sense. However, there isn’t an adequate description of the remainder of the corrections. It surely wouldn’t take someone more than a day to write down a summary of the corrections that were applied to the different stations – there are only a handful of stations. Surely part of the mission of a publicly funded organisation like NIWA is to educate people about science, refusing to provide information is hardly aiding in that mission.

    Next, your assertion that even if NZ was shown not to be warming then that would be irrelevant. That is about as good as the argument that NZ’s contribution to climate change is miniscule so therefore we don’t need to do anything. If your position is that those on the other side are idiots, then mirroring their arguments hardly speaks well for you.

    On the release of the computer code (god knows why people continue to call it “codes” as if it’s a secret set of pass phrases), nobody said “fully comment the code and make it beautiful.” They just said release it. I’m not suggesting deliberately obfuscating the material, as Phil Jones suggested doing in one of his e-mails, but I’m also not suggesting turning a half day piece of work into a massive problem.

    On comparing it to Excel, that is a silly comparison. It is equivalent to releasing the Excel spreadsheet, not to releasing the source code of Excel. People aren’t asking for the source code to the statistical package used for the manipulation, just for the workings of the manipulation itself.

    You’d have to admit that there were a bunch of corrections done to the data, and that all bar one of those corrections worked in the direction of showing an increased warming trend. Wouldn’t the law of averages suggest that some of the corrections would go the other way? Has there been no correction for urban heat island at any of the sites? Was there no increase in urbanisation in the last 100 years around any of the sites? Did none of the sites move to a lower/warmer location, they all moved to higher/colder locations? Surely you can see that this seems a bit suspicious?

    The law of averages is just that, and any one observation is quite likely to be different from the average. But when we are a fair way away from the presumed average, saying “you’re an idiot so I don’t want to give you my work”, and for a publicly funded institution to basically say “we don’t have enough time to explain our work to the public, we’re too busy doing important stuff” is, I think, a poor look.

    1. …that doesn’t mean it is OK to just refuse to provide information.

      NIWA didn’t refuse to provide information. They provided the NZ CSC with the raw station data, and in an extensive exchange of emails with the NZ CSC three years ago, provided a great deal of information about the adjustments that were made (I expect to be able to say more about that soon).

      Wouldn’t the law of averages suggest that some of the corrections would go the other way?

      There is no such thing as a “law of averages”. The adjustments are determined by the station moves (etc), and so you would only expect “cooling” adjustments if the stations moved to lower altitudes. Since most of them either started or remained close to sea level, you would only get a cooling adjustment if you moved the station below sea level. I think you’ll agree that’s not a reasonable expectation…

  6. Are you saying there is nothing else adjusted for than station location? No heat island adjustments? Surely Kelburn today looks a fair bit different than Kelburn in the 1930s. If all the adjustments are for location change, then it would presumably take about 10 minutes to summarise that.

    If there has been an extensive series of e-mails, why would that same information not be made available on the NIWA web site? I have nothing to do with the CSC, and I’m certainly not going to be e-mailing them asking for the e-mails. But I’d be interested in the content of the adjustments.

    At the moment I have an argument that I’d like to have a personal opinion on. The folks in the CSC side clearly have problems with their analysis, and don’t look all that scientifically competent to me. On the NIWA side, I have obfuscation and lack of information. I don’t know who to believe, and a bit of public domain information would help me a lot in forming an opinion.

    As you say, this debate is intensely politicised and polarised. There is no good way to form an opinion other than some decent information being made available. “That information was provided in an e-mail 3 years ago to some folks that you have no association with” isn’t what I have in mind. It would make sense to me that NIWA provide this kind of information directly on their website, then they wouldn’t have to get into endless e-mail exchanges with organisations like CSC

    1. It would make sense to me that NIWA provide this kind of information directly on their website, then they wouldn’t have to get into endless e-mail exchanges with organisations like CSC

      See Phil’s comment at #13 above. You have to remember that this stuff was regarded as non-controversial until very recently — until, in fact, the NZ CSC started to agitate. Equally, until April 2007 NIWA did not/could not (because of CRI funding and structure) release climate data FOC. They were (and continue) to be happy to help though. In every dealing I’ve had with scientists at NIWA I have always had a positive helpful response…
      Will NIWA expand their web site section on current climate to make data access easy, and provide a full set of metadata about station adjustments? I suspect that they’d be happy to do that — but it will take time and money to deliver. Perhaps Rodney would be better off asking for money to do that, instead of adding his support to those smearing scientists.

  7. 1. They already have, on their website, a summary of the Wellington adjustments. Would it take more than about a day to flesh that out with the other adjustments? That would deal with this specific issue.

    2. More money can be an answer to getting things done. Another way might be to reprioritise within the funding available. Every area of government would like to have more money, I’m not all that convinced by the refrain “get us more funding and we’ll do it.” I’m sure Rodney would be happy to go through a list of everything that NIWA does and suggest areas that might not be necessary. But that is probably a debate for another day. At the moment I’m interested in this specific issue.

    3. On my other questions, I note that you’ve pretty much ducked all them. Do you happen to know whether there are any other adjustments/corrections made to the data than purely for location change?

    4. Do you accept that providing the code – i.e. the statistical adjustments that were made – is not all that onerous, and not akin to providing the source code for Excel?

    5. I suspect the concern around “code” relates to offshore debates where genuine models are being used. My brief look at what’s going on here is that the statistical adjustment wouldn’t really fit within the definition of code – looks like a simple subtraction of an average difference. If that’s all it is, then providing the “code” shouldn’t be all that hard – it’s probably just a spreadsheet.

    1. 1. It quite possibly would – these may be adjustments which were made before computerization. Digging up the information might not be as simple as opening a folder on a network share.

      2. Good luck with that. To me, answering a never-ending series of questions from cranks is a waste of public money (and a more precious resource: the scientists’ time)

      3. your questions are already answered on this page if you read fully.

      4&5. papers on the process exist. It has been explained in detail. You don’t need “code” or a spreadsheet; it is a meaningless demand.

    2. Re Wellington: the stuff on the web illustrates how these adjustments can be done, but is not a complete description of the adjustments done to the full Wellington record. Pulling all of this information together for all of the stations in the series is not a trivial matter. Remember, much of the work was done before computers were common on desktops, and historical adjustments are usually only made once. Current data is added to the end of the series, but changes to the earlier stuff are only made if improvements are possible.

      I haven’t ducked anything. I don’t hold all the information. The majority of adjustments would have been for station moves, but other corrections are possible.

      The statistical techniques used in the correction process may or may not be trivial — it depends on the site and approach used. But I do agree that they are not likely to be difficult to implement. A historical record based on 7 stations is a rather different beast to a global record based on 1,000s…

      You, however, seem to want to skip the central point: this whole fuss over NIWA data is based on a facile analysis, and is nothing more than a attempt to smear NZ’s climate scientists, cashing in on the beat-up over CRU emails. It’s nothing to do with science — pure politics, red in tooth and claw.

    3. Only NIWA can answer many of your queries but I would expect adjustments related to instrument replacement and station housing changes at least.

      UHI – please read some literature. Broadly the effect has been found to be reasonably approximated by inverse of size and average wind speed. Plugging in the no.s and wellington is effectively rural; only a few stations could possibly have an effect.

      1. Phil: yes, for Wellington. Is that also true for all the other NZ sites? I still have some reservation about the fact that all the corrections bar one appear to have been in the direction of showing increased warming. It is a red flag. It may be valid, but without knowing what the corrections were and why, it is hard to have an opinion.

        1. “All” the corrections for the entire set of NZ stations won’t show a great amount of warming, but the overwhelming majority show an unmistakeable amount of warming, and they are rural almost exclusively by the kind of criteria used to assess this – which anyone who knows anything about NZ’s climatological history and public service setup already knows. None of it was even remotely “controversial” until recently, and this whole mess is just a cynical ploy by the “antis” to be vexatious and to annoy the hell out of people who are trying to get on with their research, the whole point being to cause distractions and a feeling of public uncertainty, since the average member of the public knows absolutely nothing about meteorology in general and climatology in particular.

          Before you start ranting about red flags, do some proper research of your own and learn something about our climate history, about which you arec clearly ignorant. And nothwithstanding general public ignorance, produce me even one intellectually coherent 80-year old who doesn’t think things are warmer than they used to be.

  8. Bugger. I hadn’t finished that (obviously).

    I see that climate science has becoming increasingly political for some time. You see it in organisations like the CSC who have little to no scientific content in their critiques. I see it in the IPCC process and other processes that tend to pick the politically desirable information, rather than the scientifically relevant information.

    I know you think the e-mail leak is just noise, but it does go some way to confirm the level of political work that is going on behind the scenes, v’s pure science.

    The problem is, if we’re talking about a political process and not a scientific process, then the rules of opinion forming become quite different. When it’s a genuine scientific process, I’m generally happy to work off peer reviewed science, tempered with some suspicion about the reporting of that science (which is usually wrong) and the amount of credibility I give to outlier results.

    If this is a political process, then I get much more worried about “consensus” – I am well aware from politics that the fact that lots of people think something doesn’t make it good or right.

    A good example for me is the ETS. It has quite a lot of support (enough to pass parliament). That doesn’t make it good. It has a lot of flaws, and fundamentally I see emissions trading as a mechanism to satisfy rent seeking behaviour from large corporates and other interest groups. Politically it is therefore good, but in a public policy sense I strongly believe that a carbon tax would be a much better response. Much of what is going on in climate science, or more accurately the whole edifice that is being built up around climate science, is overtly political. We cannot treat it as if it were absolutely true or untrue, it is usually some sort of blend of grey on the facts, plus a fair bit of opinion.

  9. C”S”C doesnt do science. Neither does IPCC for that matter – it summarizes published science for the purpose of informing governments. When scientists are told to produce results that match what a politician wants to see, then you have politicized science. Good luck on that as numerous politicians have found on a great many issues.

    An ETS isnt much to do with science either – its a response to science and like all responses is bound up in ideological conflicts, economic and other political factors.

    Lets draw the line on science here – if you are trying to model (explicate) natural phenomena and testing your model against observations then you may make a claim to science. Your expression of that model and method of collecting observations will also have conform to certain expectations (which have changed over the centuries) to be acceptable to other scientists.

    ETS, taxes, other enactments of governments are not science but it is the duty of scientists to inform governments (and thus the public in democracies) on results of research which may have an impact on public policy. The disputes about measurements, methods, and models here are a great deal less about matters of opinion and more of attempt to shoot the messenger which has once again brought unwelcome news.

  10. The politics is in what you do with the evidence, not the science that delivers that evidence. That’s not what cranks/sceptics/deniers want you to think, however. Try this piece on manufacturing doubt by Jeff Masters, for a perspective on how it’s been a deliberate tactic.

    We could go all post-modern on this, of course, and over analyse the way stuff gets interpreted, but there’s one basic message that (thankfully) seems to have got through to the world’s leaders: we have a problem, and we need to do something. Will we do enough? That’s the really, really big question…

  11. I agree that climate change is now a mainly political issue and that the NIWA calculations have become part of the debate. It is usually dangerous to agree with anything raised by your political opponent. On the other hand, you don’t want to get backed into a corner where you appear to be defending some indefensible principle.

    Presumably, the NIWA data and analyses (and codes?) were all developed by public servants during working hours. The information was paid for by the public and ought to be available to the public at large. Suppressing information is not a good look.

    But it would be a bigger worry if the public (especially the media) got the impression that NIWA was reluctant to allow any critics to have access to its technical work. The expectation – and its quite an appropriate one – is that most scientists would jump at the chance to show off their work and demonstrate their cleverness.

    1. Where on earth do you get the idea that NIWA is reluctant to release its data and methods. A publication has already been given, the data is downloadable for free (thats how treadgold got it).

      As to data collection. NIWA scientists are employees of a private company. The data collection was paid for by government but until recently maintaining databases and public delivery systems were not as far as I know.

    2. NIWA is a Crown Research Institute — constituted as a private company, tasked with making a return to the Crown, and only partially funded by government. This is not the place to discuss the strengths or weaknesses of that system, but you cannot fairly describe CRI scientists as public servants. Much of the work they do is funded by third parties, and often (too often, some would argue) subject to IP restrictions.

      NIWA has never been reluctant to take its work to the public. Most of the scientists I know have a considerable commitment to outreach, both to the public and media. The NZ CSC’s assertions that stuff has been hidden, or that NIWA has refused to release information, is just baseless nonsense.

  12. See, that is where I have a problem. I’ll happily agree we’re warming. I’ll happily agree it is correlated with CO2 and other gases. I’ll happily agree that the models we have are reasonably closely modeling the past (give or take a bit for year to year / decade to decade natural variation).

    What I am not so sure about is that the models correctly predict the future. Most of them are not predicting a straight line, they’re predicting a curve (not the famous hockey stick, but in concept similar). This is predicated on positive feedbacks, and I am sceptical about positive feedbacks. Further, while the models are in agreement, the peer review process tends to have a confirmation bias – the peer review process uses as a criteria the alignment between a new model and older models. There is a tendency therefore for newer models to confirm older models (and vice versa). This bit of the science to me looks quite political.

    So, I’ll happily agree we should do something. But the question of whether that something is “enough” is a very political one. Even what that something is – adaptation v’s prevention – is a political question. The science sheds little light on these things unfortunately. And there are (even if you might deny it) some doubts around aspects of the science. Not to the extent that it makes the difference between “warming” v’s “not-warming”, but certainly the difference between “the ice melts and we all drown” and “some rich people’s houses get eroded”. One of those I’d agree with spending public money to prevent….

    1. “This is predicated on positive feedbacks, and I am sceptical about positive feedbacks.”

      Huh??! what the hell have you read about this??
      1/ As ocean warms it can absorb less Co2. This is kind of basic.
      2/ Ocean water and rock have much lower albedo than ice so as ice melts albedo drops.
      3/ As methane hydrates warm, then release methane.

      Major positive feedbacks. What is there to be skeptical about here? Really good luck finding a model with ice ages where you can do without this. For all the uncertainities in paleoclimate, it does constrain the minimum values for feedback.

    2. I’ll add one feedback to Phil’s list: water vapour. A warmer atmosphere can hold more water, and because water vapour is a GHG, so on, etc, und so weiter.

      Climate models do not/cannot “correctly predict” the future, because what happens depends to a greater or lesser extent on what we do about the problem. There are also the known unknowns (which is where I would place methane hydrates), and the unknown unknowns, aka nasty surprises. Could there be a get out of jail free card? It’s possible, but only remotely. I certainly wouldn’t be basing public policy on its existence.

      We know enough to act. We know that adaptation and mitigation will both be required, and we know it will get worse before it gets better. This is inevitably fuzzy knowledge, but it’s the best we’ve got…

  13. Well, I’m glad to hear NIWA is not reluctant to release its data and methods. Shouldn’t be any issue here, then.

    Positive feedbacks? I agree that a warming ocean would release more CO2 and H2O, but that means more clouds and so a greater albedo, doesn’t it?

    Also, do you have any ocean temperature figure or trends for the past 30 years (perhaps a URL)? I heard that ocean temps seemed to be driven more by oscillations than by atmospheric temps.

  14. My view on feedback is formed by relatively simplistic analysis. If our climate is so finely balanced that a relatively small temperature increase causes a runaway change towards some new (warmer) stable state, it seems unusual to me that over our planet’s very long history this doesn’t appear to have every happened (i.e. there aren’t a lot of periods that are substantially warmer than now).

    Conversely, there are a lot of periods that are substantially colder than now (ice ages). So it seems to me reasonably logical that whatever feedbacks there are are probably net negative – pushing us towards a colder climate.

    Unless we are postulating a climate that has a number of stable states, with feedbacks driving us rapidly from one stable state to another (i.e. a cold-state that correlates to ice ages, a mid-state that correlates to now and similar warm periods, and an as-yet-unseen hot state that we haven’t seen as yet in any climate history). I guess it’s possible, it just doesn’t seem all that likely.

    I thought one of the major unmodelled negative feedbacks was cloud formation in the tropical regions?

    1. PaulL, it would really help this discussion if you read the IPCC AR4 WG1 so you came into the debate with your head around the basics. Most of earth’s history has been warmer – we are really in an ice age. The riddle is how come we have been getting slowly colder while sun has been warming (on a billion year scale of course). The answer is gradual removing of CO2 from atmosphere by geological processes which are very very slow. Earlier times had much more CO2 in atmosphere.

      Cloud feedbacks are area where this are still largish uncertainties in feedback – they are hardly unmodelled and research has reduced the uncertainty substantially since the IPCC TAR. There is a nice little diagram on this in the AR4 WG1 SPM. Go look at

  15. Hmm. I have heard about low level stratiform clouds for a while, and I thought there was consensus they were a positive feedback. I thought high level tropical clouds were the unmodelled negative feedback. There is even a genuine peer-reviewed paper discussing it.

  16. Thanks for the ref http://icoads.noaa.gov. Not too easy to find, but it seems to confirm that the changes in sea surface temperatures in the past 50 years have all been within the margins of error. If that continues for the next 50 years, it seems to me the modelling should ignore any feedbacks (in either direction) which would theoretically arise from warming oceans.

    Now, I know Phil said “total ocean content”, but I have a couple of problems with that. First, evaporation occurs at the surface (which is driven by oscillations) and secondly, there doesn’t seem to be any confident temp records of key areas like the Southern Ocean.

    1. RealClimate has just recently set up a page with links to climate data (like icoads). IPCC report WG1 has this rather massive bibliography with the critical papers on ocean heat.

      1. Look you lot, I nip out for a curry, and I find you bickering over music. That’s my job.

        Both Sides Now is a Joni Mitchell song (correct R2), written in ’67 and on her (appropriately titled) album Clouds, but the first commercial release of the song was by Judy Collins (forgivable, Rob).

        I prefer Big Yellow Taxi, or Coyote, or A Case Of You.

  17. Uh, isn’t there a bit larger issue here?

    Depending on who you look at as an authority, we have various temperature reconstructions going back anywhere from 1,000 years to many millions of years.

    Ann arbitrary 30-year period of recent vintage has been selected as “normal”.

    Go back and read the original Lamb, from East Anglica, on the climate history of the world.

    The larger question is, given the length of the inferred record, is a 30-year base period statistically defensible? Can you select any arbitrary 30-year period and make accurate hindcasts and forecasts from that point? If you can demonstrate that it is, was the correct 30-year period chosen?

    A second part of the question is do you actually understand the role the sun’s activity plays in shaping climate?

    This 3rd rock has been around for 4.5 billion years. It has had no atmosphere and now has one. There have been blooms of life and mass extinctions. There have been periods of tropics and periods of ice ages. CO2 concentrations have been higher and they have been lower. Sometimes it is warm and sometimes it is cold. Sometimes lava flowed freely over vast areas, and sometimes not. Whatever caused these documented events in the geologic record is unknown, as there is no comprehensive theory that explains the ice ages or much of anything else to a reasonable consensus of current scientific opinion.

    Lamb pretty well demonstrated with timely contemporary documented proof areas and times when it has been warmer, and colder.

    Heated debate about thermometers over the last 150 years is a bit juvenile. But it is worth noting that if an agency has a standard for properly locating an observation station, should it not be observed/enforced?

    Oh, and as side note, areas ‘x’ meters from the shore and above the shore consistently show lower highs and higher lows than stations farther above or away from the shore. It ain’t a local thing.

    1. The 30 number isnt arbitary – is based on the statistical estimates of internal variability in the instrument record.

      Paleoclimate records are a very different issue since you have changes on much larger scales but also larger errors in both estimate of temperature and time.

        1. Thanks R2D2. This is an area I know very little about and it is interesting reading. It certainly looks like progress is being made in this area and may affect global agreements.

  18. Hi Terry – yes it is all very interesting to discuss the ‘big picture’ of climate change over the eons (and as Phil mentioned above, quite interesting how the earth has managed to cool the climate whilst the sun is getting hotter by slowly sequestering CO2 from the atmosphere).

    However, on that perspective, you must agree that a doubling of CO2 in little over 200 years (a blink of the geological eye) is actually a major intervention on this system of slow climate cycles and feedbacks. It is going to have a major effect on the climate. In an extremely short period of time (geologically speaking, although in human terms a hundred years or so seems like a long time).

    Now the question of what is ‘normal’ climate may be academic when you’re discussing changes over millions of years – but it is not academic when you’re discussing the last few hundred years (in other words, what we have built our civilisation around). In that context it is critical that we do understand how big the climate impact of our activities is likely to be. And taking 30 year averages over our recent history seems entirely reasonable in that context.

Leave a Reply