Talk:Climate change

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New Articles: Global climate change and Climate forcings

Please read the new articles and consider commenting on them and/or moving some material to either one. Note that climate forcings is not specific to global climate forcings, so if it makes sense to create a separate section please do.

I hope this helps get this part of Wikipedia sorted out.

Posted to all discussion pages listed in the "See Also" section of global climate change. --Ben 03:48, 2 Dec 2004 (UTC)

Reverted addition of the Science magazine article

Are you kidding me? You wrote "There is no evidence that "Science Magazine" reviewed any "papers" as described." in the edit summary and reverted without any discussion on the talk page. That is irresponsible. The article was paraphrased in good faith and the article text itself is evidence that she conducted the review. I did in fact cite it incorrectly as the references in the article do show the review was not done by Science, but apparently Oreskes herself, and the essay was excerpted by Science from another work. Oreskes is a relatively reliable source. [1] Because this was added in good faith and does have a well referenced source for the claim, the burden of proof is with the claim that the review was not conducted, not the other way around. It should have been corrected, not removed. - Taxman 16:59, Dec 11, 2004 (UTC)

(William M. Connolley 17:54, 11 Dec 2004 (UTC)) I agree with you on this, and think that Silverback goes way too far in criticising Oreskes, based (IMHO) on his dislike of the result. I've said that elsewhere. However I'm now going to argue in favour of not putting this text at the start of the GW page, and perhaps not on the page at all. I think the O piece belongs on scientific opinion on climate change (and it is there too) and sits rather uncomfortably at the start of the GW piece. I've just beefed up the intro of Attribution of recent climate change (partly in response to the extra ammo provided by the O survey) and I suggest we cut the O text on this page and replace it with:

I disagree. The main article on global warming should reflect the current scientific consensus, and provide references for the best material to back that claim up. Leaving it off to another article is all well and good for the background material, but the main claim and references should be in the main article. I suppose I agree that the entire section describing the Oreskes paper is too much for the intro, and what you have written below is closer to what needs to be there. But the larger explanation that is currently in Scientific opionion... should be included in this article. - Taxman 22:34, Dec 12, 2004 (UTC)

The current scientific consensus is that most of the warming observed over the last 50 years is attributable to human activities (see Attribution of recent climate change) and the extent of this consensus is discussed at scientific opinion on climate change.

Begin Silverback. You should assume good faith. My problem is with the validity and meaningfulness of the results. If she had reviewed the actual papers, published the standards she used, and had the categorizations checked by independent reviewers for compliance with those standards, and came to conclusions supportable by the methods she used, I would have no problems with it. As it is, there is no way to tell what is meant by support for the consensus especially for papers before 2001 or not directly addressing the more disputed part of the consensus or whether the underlying papers would be classified the same way the abstracts were. The classification, would involve some subjectivity anyway, but there is no sign she attempted to conform to the standards of even her own field. Frankly, I happen to believe there is a consensus, although I doubt it is as complete and as unquestioning of the full 2001 IPCC statement as this essay implies.--Silverback 07:55, 12 Dec 2004 (UTC)

(William M. Connolley 10:30, 12 Dec 2004 (UTC)) Hmmm, well, given that you've ripped O out again I've put in my proposed text.

Reverting a valid edit without even discussing it on the talk page and reverting it again after being asked not to hardly qualifies you for good faith, Silverback. In fact, both are examples of very bad wikiquette. That you dispute the validity of Oreskes results is one thing, but the fact is that she does, as published in Science currently make the claim that I added to the article. That means that the text you have reverted twice is better attributed than 99.9% of material on Wikipedia. Do you plan to revert all of that material too, or just the ones you disagree with?

I am asking again, before intervention is needed, do not revert addition of a valid source. Discuss it here, and if consensus agrees with you, then it will be removed. - Taxman 22:34, Dec 12, 2004 (UTC)

The Oreskes reference does belong here and I agree with Taxman that a summary of the report does belong in a prominent position in this page as it has direct bearing on the topic regardless of whether it is on other GW related page, this is the main one and it is pertinent. -Vsmith 17:21, 13 Dec 2004 (UTC)

NPOV disputed

This article has many good sections, but it also has strong POV in many other sections. The following excerpts from the article correctly show that there exists controversy and dispute over the significance of global warming, and in particular, controversy over the human causal nature of global warming.

(the neutrality of these particular excerpts is not being disputed)

• "the brighter sun and higher levels of so-called "greenhouse gases" both contributed to the change in the Earth's temperature, but it was impossible to say which had the greater impact."
• "Various other hypotheses have been proposed, including but not limited to:

1. The warming is within the range of natural variation and needs no particular explanation

2. The warming is a consequence of coming out of a prior cool period -- the Little ice age -- and needs no other explanation."

• "Other scientists theorize global temperature change may in fact be induced by natural causes, such as volcanism and solar activity."
• "Over the past century or so the global (land + sea) temperature has increased by approximately 0.4-0.8 C"
• "It is thought by geologists that the Earth experienced global warming in the early Jurassic period, with average temperatures rising by 5 Celsius (9 Fahrenheit)."

But despite this article having these statements showing the scientific controversy and dispute over the significance and human-causation of global warming, the article has a number of strong POV sections where it expresses a view that global warming is an absolute and undisputed certainty. These need to be fixed and brought into NPOV.

Some examples of these areas are:

• All climate models further predict that temperatures will continue to increase in the future, if human emissions of greenhouse gases continue and there are no significant changes in solar output or volcanic activity.
  • This presents the impression that there are NO theories under which global warming will not occur. This is not the case, and it should be reworded to a more NPOV statement. The word "All" is blatant POV, and the statement should also be followed by a NPOV clarifier which indicates that there also exist theories which claim that observed temperature changes are due to more natural causes.
  • (William M. Connolley 23:16, 16 Dec 2004 (UTC)) The statement - that all climate models predict increases of T if GHGs continue to increase - is correct. *All* is literally correct. If you dispute it, rather than hand-waving about NPOV you should simply produce a counterexample.
    • For the simplest example, any model which includes the sun (kind of a useful thing to include) says that global temperatures can decrease irrespective of GHG changes with a small but significant decrease in solar output.
      • (William M. Connolley 09:46, 17 Dec 2004 (UTC)) Oh good grief, read the text: All climate models further predict that temperatures will continue to increase in the future, if human emissions of greenhouse gases continue and there are no significant changes in solar output or volcanic activity. the all climate models predict... is clearly predicated on (a) GHG increase and (b) no sig changes elsewhere.
    • For another, Global cooling, widely believed in the 1970's, put forth the model that other pollutants would dominate over GHG increase, causing a net decrease in temperature, which for a time they did observe.
      • (William M. Connolley 09:46, 17 Dec 2004 (UTC)) I'm familiar with the cooling page. "Widely believed" is dubious - read the page. But more, you're once again *failing to read the text you complain about* - see above.
    • For a third, there are theories containing feedback mechanisms such as biomass increase which could balance out GHG levels, or feedback mechanisms which could cause temperature to stabilize. So it's complete POV to say "all" models predict human GHG emission will raise temperature. — Cortonin | Talk 23:48, 16 Dec 2004 (UTC)
      • (William M. Connolley 09:46, 17 Dec 2004 (UTC)) Thats nice, why don't you find a model incorporating such feedbacks that predicts cooling, then come back.
• The current scientific consensus is that most of the warming observed over the last 50 years is attributable to human activities (see Attribution of recent climate change) and the extent of this consensus is discussed at scientific opinion on climate change.
  • This is not the case. The IPCC report states that "the balance of evidence suggests that there is a discernible human influence on global climate" and that "There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities", but it does not claim that there is a consensus that global warming was caused by human behavior. In fact, it states, "our ability to quantify the human influence on global climate is currently limited because the expected signal is still emerging from the noise of natural variability". The summary descriptions need to have a NPOV which takes into account dispute, areas of uncertainty, and that research is still ongoing.
  • (William M. Connolley 23:16, 16 Dec 2004 (UTC)) You're wrong. The text you quote is from the SAR [2] and doesn't reflect the *current* consensus.
    • Please read this page from the article you just referenced, which describes the uncertainties which still exist: [3] In particular, " The precise magnitude of natural internal climate variability remains uncertain.", "Some palaeoclimatic reconstructions of temperature suggest that multi-decadal variability in the pre-industrial era was higher than that generated internally by models", etc. Read the rest. — Cortonin | Talk 23:40, 16 Dec 2004 (UTC)
      • (William M. Connolley 09:46, 17 Dec 2004 (UTC)) Uhu, so you're admitting your quote is actually from the SAR? Good, tahts progress. As for your other quotes: yes indeed, they are quite plausible (I haven't checked them, but they sound quite right). So what?
  • In addition, the phrase "most of the warming" implies that the warming which has occured is large. By the evidence later in the article, the warming over the last century is measured to be about 0.4 to 0.8 C. This is small in comparison to natural fluctuations in temperature which have occured before the existence of humans, such as the quote from this same article which refers to a 5 C fluctuation during the Jurassic period.
  • (William M. Connolley 23:16, 16 Dec 2004 (UTC)) This is silly. We're talking about current warming, not stuff that happened millions of years ago. The earth was once molten: are you going to start claiming that the long-term trend is therefore clearly one of cooling?
    • The Earth was not molten during the Jurassic period. The entire point of that refutation is that the current warming is well within the range of fluctuations over the last millions of years, so yes, we are talking about the entire history of the Earth. It doesn't benefit to only look at the dataset which supports ones point, that's selection of fact and that's POV. — Cortonin | Talk 23:29, 16 Dec 2004 (UTC)
      • (William M. Connolley 09:46, 17 Dec 2004 (UTC)) If you're prepared to go back 10s of millions of years, why not billions?
• The observed warming of the Earth over the past 50 years appears to be at odds with the skeptics' theory that climate feedbacks will cancel out the CO2 warming.
  • First, the word "skeptic" implies that all people who question global warming do so out of a habitual questioning of accepted conclusions or religious matters. This is POV, and instead NPOV words like critics, or phrases like "critics of global warming" should be used.
  • (William M. Connolley 23:16, 16 Dec 2004 (UTC)) Oh good grief, go read the arguments over at global warming skeptic over the use of the term "skeptic". But its established practice and won't get changed.
    • I see that you are the primary author of the article global warming skeptic (with approximately half of the edits being yours), which perhaps explains the usage of the term here. But that does not change the fact that usage of the term is dismissive POV. Skeptic definition. — Cortonin | Talk 23:27, 16 Dec 2004 (UTC)
      • (William M. Connolley 09:46, 17 Dec 2004 (UTC)) You have it exactly backwards. I disapprove of the use of the term skeptic (see http://mustelid.blogspot.com/2004/12/septics-and-skeptics-denialists-and.html) because I feel its overly generous to them - denialists would be better perhaps. But its the term we're stuck with.
  • Second, this excerpt blatantly ignores the other scientific explanations for temperature increases based on other factors, such as are described elsewhere in the article. It uses a false dichotomy, and it creates strong POV.

Please do not remove the NPOV dispute until these issues are resolved and until the article (in particular the beginning 1/3 of the article) has a NPOV which acknowledges the existence of theories disputing the significance and causal nature of global warming, acknowledges the uncertainties and significance level of existing data, and does not overstate the scientific consensus about the human-causal component of global warming. — Cortonin | Talk 22:44, 16 Dec 2004 (UTC)

(William M. Connolley 23:16, 16 Dec 2004 (UTC)) The article, correctly, states that the consensus is what IPCC says it is. You need to put up (find a model that shows cooling).

I refer you to Scientific_opinion_on_climate_change#IPCC and Global cooling. — Cortonin | Talk 23:53, 16 Dec 2004 (UTC)

(William M. Connolley 09:46, 17 Dec 2004 (UTC)) Again, I'm very familiar with both of those pages and they are perfectly compatible with this page, so (given your failure to find a model for cooling) I've removed the NPOV header.

You do not just "remove" an NPOV dispute because you don't agree with it. That defeats the entire purpose of NPOV disputes, because it's the POV you're influencing here which is being disputed. I see on your user page that you are a GW modeller,

(William M. Connolley 18:47, 17 Dec 2004 (UTC)) Your inability to read does you no credit. I'm a climate modeller, like it says.

which is all fine and good, but then you make the leap of illogic and say that everyone who questions GW is dishonest, in denial, or a liar.

(William M. Connolley 18:47, 17 Dec 2004 (UTC)) I don't say that explicitly, and just for the record I don't believe it.

To make matters worse, you have reflected this view on the text of this article. The NPOV dispute stands until the article does not reflect this strong POV. — Cortonin | Talk 18:34, 17 Dec 2004 (UTC)

(William M. Connolley 18:47, 17 Dec 2004 (UTC)) I removed the tag because your arguments are all insubstantial. You quote from the SAR when you think you're quoting the TAR. You assert that there exist models predicting cooling but then can't find any.

First, I said "IPCC report", and made no reference to which version.

(William M. Connolley 20:16, 17 Dec 2004 (UTC)) You said *the* IPCC report (my italics). *the* in this context means one not many, and means the most rescent, the TAR. And since we're talking about the *current* consensus, not one of 6+ years ago, its obviously out of order to be quoting the SAR, even if you did it by mistake.

I should hope you already know they are both IPCC reports, and that you are just piddling over details for the sake of argument. The same goes for the Jurassic temperature fluctuations.

Second, you said that global warming critics are just in denial. It's fine if you want to believe that, but you need to stop forcing that POV into the article.

(William M. Connolley 20:16, 17 Dec 2004 (UTC)) Can you source that please?

"I disapprove of the use of the term skeptic ... because I feel its overly generous to them - denialists would be better perhaps." So says William M. Connolley, only a few lines above. — Cortonin | Talk 22:19, 17 Dec 2004 (UTC)

(William M. Connolley 22:29, 17 Dec 2004 (UTC)) Uhu - so, as you've just proved, I didn't say skeptics are in denial. I said that denialists would perhaps be better. There is no good term (see >here (as ref'd above) for my full opinion).

Third, please take a moment to read the NPOV tutorial. In particular, note the definition of POV there which is, "It's what everybody I know believes." Then read the sections on how to avoid POV and guide articles into a NPOV fashion. We need to work together to establish NPOV, not get into ridiculous edit wars. — Cortonin | Talk 19:17, 17 Dec 2004 (UTC)

(William M. Connolley 20:16, 17 Dec 2004 (UTC)) I've read the NPOV - skeptics constantly use it to try to force their opinions into various GW articles.

So your argument is that you don't like NPOV because it allows the perspectives of "skeptics" into the GW articles? That of course, is precisely why we DO have NPOV at Wikipedia. — Cortonin | Talk 22:19, 17 Dec 2004 (UTC)

(William M. Connolley 22:29, 17 Dec 2004 (UTC)) I like NPOV. Its a good idea. But people misunderstand it.

However, WillyC (William M. Connolley Ahem) seems to be correct on at least a few points, which I think you should acknowledge. I.e., you should specify what climate models you believe demonstrate that global cooling could occur along with increasing GHG and no change in solar or volcanic activity. Also, since you are talking about the current consensus, Billiam is correct in that you should be quoting the TAR (third assessment report) and not the SAR (second assessment report). If you feel that you can meet these arguments fairly on the field of battle, then we have grounds for an actual dispute. Otherwise, I'd have to say the balance of the evidence rests in W's camp. Graft 19:24, 17 Dec 2004 (UTC)

"The observed warming of the Earth over the past 50 years appears to be at odds with the critics' theory that climate feedbacks will cancel out the CO2 warming."

• I note that no one bothered to address the false dichotomy I raised here, even though my edit correcting this was reverted. That is strong POV. — Cortonin | Talk 19:37, 17 Dec 2004 (UTC)

(William M. Connolley 20:16, 17 Dec 2004 (UTC)) The statement appears to be obviously true. Why do you object to it?

Because it's an obvious false dichotomy. It says that "Either feedback cancels out CO2 warming" or "the earth will warm". This ignores the fact that there are a large quantity of other possibilities, such as alternate variables unrelated to feedback or CO2 which also affect the temperature of the Earth, and also solar fluctuations which have definitely been observed to have a large impact on the temperature of the Earth. So to say that there are two options, and then to draw a conclusion by refuting one of those two options and saying the other is correct is what's called false dichotomy, and it is listed as a logical fallacy for good reason. — Cortonin | Talk 22:19, 17 Dec 2004 (UTC)

(William M. Connolley 22:29, 17 Dec 2004 (UTC)) But skeptics also attribute all the warming to solar variations. I've never seen a single skeptic argue that solar variation is acting to *cool* the earth. Are you arguing that solar acts to cool?

"Critics have been unable to produce a credible model of the climate that does not predict that temperatures will increase in the future."

• This sentence still remains in the article, and has no qualifier about solar activity changes, even though no one has disputed that solar activity could potentially dominate over GHG's. — Cortonin | Talk 19:37, 17 Dec 2004 (UTC)

(William M. Connolley 20:16, 17 Dec 2004 (UTC)) I've never seen a single scientific paper asserting that solar would dominate over GHG over the next century. Have you? Or even a web page?

As for theories which do not predict warming, here are two from the article:

1. "The warming is within the range of natural variation and needs no particular explanation"
2. "The warming is a consequence of coming out of a prior cool period — the Little ice age — and needs no other explanation."

These are listed, and then summarily dismissed at other locations, occasionally with the word "credible" thrown in to imply that they are somehow not credible. This of course means, not believable. But not believable by whom? POV. — Cortonin | Talk 19:37, 17 Dec 2004 (UTC)

(William M. Connolley 20:16, 17 Dec 2004 (UTC)) When these theories are examined, they are found to be wanting.

You may find them "wanting", but they still EXIST. You cannot say "all" say another thing. Leave out the word all, or any similar sweeping generalities. — Cortonin | Talk 22:09, 17 Dec 2004 (UTC)

(William M. Connolley 22:29, 17 Dec 2004 (UTC)) I've re-inserted "all", since its true, as it says: all-models-predict-warming-given-co2-forcing. You may not like it, but your failure to find a counterexample is becoming rather glaring.

I listed numerous counterexamples in the above discussion, but you didn't like them. Like I said, "models" also means "theories". You cannot say that all theories state a particular thing, that is a false generalization. — Cortonin | Talk 22:41, 17 Dec 2004 (UTC)

Fair enough. However, this article is about a scientific argument, and conjecture must be supported by weight of evidence. That is, a "theory" must be a real scientific theory supported by a believable model. Thus, a reasonable climate model demonstrating that the above conjectures are valid and that, specifically, greenhouse gases do not contribute to warming. Does such a thing exist for either of the two above explanations? I'll agree that the two sentences you quote are not appropriate and should be changed, but I think this is bad prose, not POV. The paragraphs in which they lie are pretty damn choppy. Graft 19:49, 17 Dec 2004 (UTC)

I just added a specific example to the external links section which discusses the drastic climate changes 5,200 years ago as coinciding with significant solar fluctuations, and those climate changes far exceeded anything observed this century. I think observation trumps modelling here. [4] — Cortonin | Talk 19:59, 17 Dec 2004 (UTC)

(William M. Connolley 20:16, 17 Dec 2004 (UTC)) Its terribly vague about what those changes were. Were they global? Did they just affect one glacier? Have they even been published?

In addition, while to a climate modeller the phrase "model" may refer exclusively to simulations, to the rest of the science world and to the wikipedia audience, the word "model" can also refer simply to a "theory" . So when you say no models can account for it, you're not discussing simulations, you're dismissing all possible theories. This is of course wrong by definition, and can only be POV. I apologize if that wasn't clear in the above discussion. — Cortonin | Talk 19:46, 17 Dec 2004 (UTC)

In the context of the article, it's obvious that "model" refers to a scientific model of how the climate behaves. This still demands that the model (or "theory", if you will) be robust and conform to the available evidence. Graft 19:49, 17 Dec 2004 (UTC)

I think the evidence shows that any model which ignores solar fluctuations is not a very realistic model. See above. — Cortonin | Talk 20:01, 17 Dec 2004 (UTC)

Quoi? The same could be said for any model which ignores greenhouse gases. The article already refers to solar variation models and efforts to reconcile the record of current solar variation with warming, and available evidence indicates that solar variation isn't able to account for all of the warming post 1950. So... what gives? Graft 20:16, 17 Dec 2004 (UTC)

I am removing the following sentence for two reasons. "All Climate models currently predict that, in the absence of changes in solar output or volcanic activity, human emission of greenhouse gases will cause temperatures to increase in the future." One, it's biased and apparently Connolley is unwilling to let a NPOV version stand. Two, it is not part of the definition of global warming, as should be in the first paragraph. And three, it is described in a more NPOV way later in the article with the sentence "All climate models that pass these tests also predict that the net effect of adding CO₂ will be a warmer climate in the future.", which is explicitely referring to the appropriate subset of computer models. — Cortonin | Talk 22:31, 17 Dec 2004 (UTC)

(William M. Connolley 22:48, 17 Dec 2004 (UTC)) Sentence restored. The sentence is accurate, as your failure to find a single counterexample demonstrates. Please stop trying to evade the issue: your task is to find a climate model which, when forced by increased CO2, and other variables held constant, shows a cooling (or no warming). If you can do that, then remove/qualify the sentence you so dislike. If you can't, please leave it alone.

Well THAT is accurate, that's just not what the sentence said. I will correct it to match your statement here. I still think "All" weakens the statement, but I will leave it for now as a compromise with the revised sentence. — Cortonin | Talk 23:32, 17 Dec 2004 (UTC)

(William M. Connolley 23:43, 17 Dec 2004 (UTC)) Ah, have you finally read what it says rather than what you thought it said? You version is functionally equivalent, though (in my opinion) somewhat on the skeptic POV side. But I'll leave it for now in the hope that someone else will have a look.

0.6 +/- 0.2, not 0.4 - 0.8

(William M. Connolley 20:37, 17 Dec 2004 (UTC)) I've changed the estimate of the T rise from 0.4-0.8 to 0.6 +/- 0.2. See [5] if you need a source. The reason is that the two are not equivalent, though they superficially appear to be. +/- 0.2 are the 95% confidence limits; this means that not all values in the range 0.6 +/- 0.2 are equally probable, as is implied by 0.4-0.8.

Yeah, that's a sensible change. You may want to also correct it later in the article, as that's where I sourced the numbers. — Cortonin | Talk 22:33, 17 Dec 2004 (UTC)

Models predict warming...

(William M. Connolley 23:23, 17 Dec 2004 (UTC)) having paused for a think and review, I have realised that (for all my calls for C to put up or shut up) the documentation on wiki that GCMs predict warming is really rather thin. This I take as ironic proof of the strength of my case: we all know its true, so no one has bothered to contest the lack of evidence :-).

So I've just added a para+links to the climate model article to provide some evidence.

I agree that the listed evidence is quite thin. I also think that considering the climate model article says, "Whether these models are sufficiently "correct" to be useful or not is a matter of dispute," that perhaps the global warming article should reflect some of that dispute and uncertainty. It's okay for scientists in a field to be uncertain. — Cortonin | Talk 23:29, 17 Dec 2004 (UTC)

"Skeptics unable to produce model that shows temperatures decreasing"

"Skeptics have been unable to produce a model of the climate that does not predict that temperatures will increase in the future."

I am removing this statement for the following reason: The simplest model of the climate which does not predict temperature increases in the future would be solar output significantly decreasing. If you want to put it back, then it would have to say something ridiculous like, "Skeptics have been unable to produce a model of the climate that does not predict that temperature will increase in the future without taking into account any of the other possible variables which could affect the climate." — Cortonin | Talk 23:48, 17 Dec 2004 (UTC)

(William M. Connolley 23:56, 17 Dec 2004 (UTC)) Reinserted. Well, you wanted the word "credible" removed, so I did. But then of course that allows you to construct incredible models, like the one you've just mentioned. The point (and its a vlid one) is that despite the fervent desire in some quarters to avoid having CO2 increase T, not one of the credible skeptics has managed to produce a model that does so; nor have any of the skeptics produced a credible model that does so.

The other point is about whether or not CO2 increase is the primary determiner of global temperature. There are many factors which affect global temperature: solar output, water vapor concentration, surface coating (forestation, civilization, etc), etc, etc. Of course CO2 alone will cause an increase in T. Thank goodness it does, as if you subtract it from the thermodynamic balancing equations it shows up as a bit chilly down here. But it certainly is not the dominant contributer, so it is difficult to assess from simple modelling whether the variable of human output of CO2 will cause temperatures to rise given all the other variables which can simultaneously change, some of which change independently, and some of which are related to CO2 levels in a complex fashion. This is a bit too quickly dismissed in the greenhouse gas section with the argument "Well, temperatures went up a bit this century, so clearly it's due to CO2." To establish this scientifically, one needs to do one of two things:

(William M. Connolley 09:44, 18 Dec 2004 (UTC)) I don't suppose you've considered reading the scientific work that has been done, rather than making up your own? Try attribution of recent climate change.

I read it. I see much talk of consensus and opinion, and of course scientific truth is not obtained from consensus and opinion, it's obtained from evidence. When considering the evidence described on that page, it essentially all falls into two categories. One consists of statements that there are significant uncertainties existing about the contributions from internal variability and external forcing. The other consists of climate modelling. I've done enough computer modelling in my life to be a bit hesitant to take simulation results as established truth without extremely strong supporting evidence, and I don't see this being presented here. There is essentially only one significant dataset being used to compare these to, 20th century temperatures. The simulations which match those temperatures are kept, but how do you verify they're correct? You can't rerun the experiment. So greenhouse gas only simulations overestimate the amount of warming. Is it perhaps because there's a competing temperature changing consequence from greenhouse gases that isn't understood yet? Is it because the aerosols aren't included in the simulation? If you add the aerosols and then the results are closer, does that mean you got it right, or does that mean you could have missed the next thing, just like you wouldn't have stopped to add aresols if the first simulation results had matched better? It's hasty to say such simulations are definitive truth unless you can present some sort of solid evidence that's missing from all this material I've been reading. — Cortonin | Talk 10:58, 18 Dec 2004 (UTC)

1. Show longterm measurements in which CO2 levels are the only possible variable which correlates to global temperature changes, and other changes do not correlate.

2. Show that in the time that CO2 levels changed and global temperature changed, none of the other variables which can affect global temperature changed.

In the time measured (a century or so), the global average temperature has gone both up and down while CO2 levels have essentially only gone up, every other factor relating to the temperature of the Earth has changed significantly, including deforestation, emission of other gases, surface changes, (has water vapor or cloud cover changed during this time?), and even solar output is reported to have increased (the complete effects of which are only guessed at by modelling). So I think the burden of proof to show causation is a little higher than just showing a small short term correlation.

The point is not that greenhouse theory is wrong, of course greenhouse effects contribute. The point is that the climate is a complex system, at it should not be artificially reduced to simpler descriptions without experimental evidence justifying and quantifying those reductions. — Cortonin | Talk 00:16, 18 Dec 2004 (UTC)

The models do artificially reduce to simpler descriptions, and that is part of the reason WMC is correct that they all predict warming. However, there is experimental and theorectical evidence for alot of what the modelers do. The first paragraphs are entitled to present the global warming theory without a lot of qualification, since this is an article about the theory. Balance should be achieved in the latter parts of the article where the opposing views are presented. Keep in mind that even most of the skeptics accept that greenhouse gasses will cause global warming, although based on paleo data and indirect solar effects that the models don't account for, they would argue that a doubling of CO2 would only lead to a temperature increase of approx 0.6 degrees C. --Silverback 07:24, 18 Dec 2004 (UTC)

I would say quite the opposite, that the opening to an article should give the most objectively true summary possible, as by the style guides the opening is supposed to essentially be a definition and quick summary. It is the LATER part of the article which should contain various points of view and interpretations, carefully described as such, to discuss the more complex aspects of the topic. And given the qualifiers you just mentioned, that is sufficient reason to not overstate any claims in the opening section.

The opening section should never "prime" the reader with an opinion from which they should interpret the rest of the article. That's one of the more egregious forms of POV pushing. The opening section should simply present what the topic is by definition, and perhaps also an objective NPOV overview of the major issues involved. — Cortonin | Talk 08:12, 18 Dec 2004 (UTC)

YOu aren't saying the opposite, however, the objectively true summary of an article on global warming theory is a presentation of the theory itself, which should pose no POV problems, if it is presented as a theory.--Silverback 21:08, 18 Dec 2004 (UTC)

Right. Phrases like, "Global warming says this", "modelling has shown this", and "climatologists predict", would make for good objectively true summaries of global warming theory. Phrases that sound like, "All theories agree with global warming theory" should be avoided, even if they only "sound" this way. In many cases POV has more to do with presentation than with the actual content of the information being presented. — Cortonin | Talk 01:58, 19 Dec 2004 (UTC)

Significance of human induced contributions

If the precise magnitude of human induced contributions to global warming is uncertain, then how is the significance certain? If the significance is certain, what is that significance? Is there an objective answer to this based on evidence? — Cortonin | Talk 22:19, 19 Dec 2004 (UTC)

(William M. Connolley 22:38, 19 Dec 2004 (UTC)) That would depend on what you meant by significance - the main reason I deleted the word. If you mean significant in terms of cause-and-effect, then yes of course they are signigicant, by the very construction of the sentence. If you mean significant in terms ot magnitude, thats already covered.

I was reading "significance" in that context in terms of importance or relevance considering other contributing factors, but I can see the confusion about it also being misunderstood as statistical significance within the single variation. — Cortonin | Talk 23:54, 19 Dec 2004 (UTC)

Annual increases of CO2

I propose changing the sentence

"Increases in CO2 measured since 1958 at Mauna Loa show a monotonically increasing atmospheric concentration of CO2. "

to "On an annual basis, CO2 measured since 1958 at Mauna Loa has increased monotonically from 315 ppm (parts per million) to 375 ppm."

Basically because there is a ~ 3% seasonal oscillation at Mauna Loa (a smaller one in the Antarctic record, which is also interesting) as can be seen at http://cdiac.esd.ornl.gov/trends/co2/graphics/mlo144e_thrudc03.pdf

And putting similar language on the CO2 graph

(William M. Connolley 10:52, 23 Dec 2004 (UTC)) Thats OK - just go ahead and do it (possibly also put in a mention for the seasonal osc too). BTW, sign your posts with 4 tildas, thus: ~~~~.

Ice Melt

Can I suggest an alteration to the "Potential Effects" section on ice melt to : "Global warming causes the sea level to rise because sea water expands as it warms, and through thinning of the Antarctic and Greenland ice caps and reduction of glaciers."

Melting of the North polar cap and sea ice, as it currently reads, will not of course significantly affect sea levels as they are floating ice masses.

• I don't think anyone would seriously dispute you on this. Floating ice has no effect whatsoever on water level when it melts, as it displaces precisely as much water either way.

On the other hand, it should also be mentioned that the atmosphere holds dramatically more water when warm, so that a sizable portion of the melt from the land-based glaciers would end up in the air, not the seas, because of the much greater volume of air (which is increasing in storage capacity) versus sea (which is taking up only the leftovers). Kaz 22:46, 31 Dec 2004 (UTC)

(William M. Connolley 22:58, 31 Dec 2004 (UTC)) Total moisture content of the air is slight. I don't have the figures to hand but globally it amounts to about 2-4 mm/m2, which is about one years sea level rise at current rates. Forget it. As to ice: the effect is very small but not zero, due to salinity. See sea level rise I think.

This article should at least mention the effect of melting ice on Thermohaline circulation, and thus, climate. --Ben 07:54, 1 Jan 2005 (UTC)

I added it --Ben 01:53, 3 Jan 2005 (UTC)

Global Mean

At the beginning of the article, there is acknowledgement of the fact that most widely accepted global warming models require

(William M. Connolley 22:39, 31 Dec 2004 (UTC)) Require? You mean, "predict"?

a temperature increase in atmospheric and oceanic temperatures...but then the article goes on to repeatedly cite the rise surface temperatures in reference to global warming. There should be a clear demarcation between the measurement of oceanic / atmospheric temperatures and surface temperatures.

(William M. Connolley 22:39, 31 Dec 2004 (UTC)) Surface (of land and ocean) are the best measured and with the longest series. The t rec page should (and does) say more about this.

To talk about the latter in a global warming article is quite confusing, since they have little or no effect, being mostly a result of the increase in urbanization around land-based weather stations.

(William M. Connolley 22:39, 31 Dec 2004 (UTC)) This is completely wrong. See UHI for details.

For example, the surface temperature is described as having risen .15 celcius, right after a reference to /lower/ atmospheric temperature increases (again, not considered nearly as important as upper atmosphere), but nothing is mentioned about the lack of impact of these on the global mean, regarding global warming models.

(William M. Connolley 22:39, 31 Dec 2004 (UTC)) I don't understand what you mean.

It's as if there were an article about percentage of body fat, in which references to someone growing taller were made without mention to the fact that this didn't increase body fat, per se.

We need to clear this up...global warming models call for a climb in upper atmosphere and oceanic temps, and the surface/troposphere should clearly be clearly marked as an aside. Kaz 22:22, 29 Dec 2004 (UTC)

Warming/Dimming & Silverback

(William M. Connolley 19:35, 14 Jan 2005 (UTC)) I can't say I'm terribly keen on this GD stuff myself, but "A further speculation is that an increase in global dimming would prevent such a rise in temperature" doesn't seem to be defensible. I don't know anyone who expects aerosols to increase in such a way... where does this piece of speculation come from?

I thought this section had become a license to speculate. The original idea that dimming somehow would imply an increase in the sensitivity of climate to CO2 was the original speculation, as if the current climate models don't already have a higher sensitivity to CO2 than implied by the paleo data. Perhaps this dimming is the indirect feedback that resolves the discrepency, and eventually gets the doubling prediction down to to 0.5 to 0.6 degress C range. This seemed more likely to me than the counter-intuitive speculation originally presented.--Silverback 05:24, 15 Jan 2005 (UTC)

(William M. Connolley 10:33, 15 Jan 2005 (UTC)) I don't agree with you, in essentially everything you write above. In particular, no, the section isn't a license to speculate (and that should be obvious, nowhere in wiki is; if you see stuff that you consider speculative the correct response is to remove it or query it on the talk page, not add counter-speculation): everything in it was from the BBC horizon programme, though toned down somewhat. The bits you added seem to be "personal research". Anyway, this may all be a bit irrelevant since I've subsequently cut much of that section out.

New feedbacks section

(William M. Connolley 21:21, 15 Jan 2005 (UTC)) I dislike the new section on feedbacks. The concept is OK (though I think it would fit better on the climate change page) but the section itself is badly wrong.

• Firstly, attributing the idea of positive feedbacks to Day-after-tomorrow, or Al Gore, is silly; it come close to arguing-against-by-giving-bad-sources, which is a poor mode of argument.

• Not everything has to be an argument, nor was that section intended to be. It's information which provides cultural context. — Cortonin | Talk 05:21, 16 Jan 2005 (UTC

(William M. Connolley 10:44, 16 Jan 2005 (UTC)) Oh come on. The DAT is simply wrong and has no place in a science article.

• Secondly, DAT postulates *cooling* in response to GW, which is hardly a *positive* feedback - its a strongly negative one.

• It's just a movie and not intended to be a source of information, it's mention was intended to provide cultural background. But for the record, a "negative change in temperature" is not the same as a "negative feedback". A system in which fluctuations are reduced is experiencing negative feedback, and a system in which fluctuations are amplified is experiencing positive feedback. I suggest for more information, you read the article on feedback, and you will see things like "Feedback may be negative, which tends to reduce output, or positive, which tends to increase output. ", "Positive and negative don't imply consequences of the feedback have positive or negative final effect. The negative feedback loop tends to slow down a process, while the positive feedback loop tends to accelerate it.", and "The negative feedback helps to maintain stability in a system in spite of external changes. It is related to homeostasis. Positive feedback amplifies possibilities of divergences". — Cortonin | Talk 23:08, 18 Jan 2005 (UTC)

(William M. Connolley 23:23, 18 Jan 2005 (UTC)) Well thats all very nice, and presumably an attempt to avoid admitting that you're wrong, but why don't we read the text that you actually put into the page which was: Feedback mechanisms involved with global warming can be either positive feedback, where the feedback causes an unstable increase in temperature.... So DAT *isn't consistent with your own text*.

• Thirdly, +ve feedback, in the conventional sense, *does not* postulate an unstable equilibrium. No one (or at least, not the consensus view) is suggesting that the climate is like a pencil poised on its nose, ready to fall off into a new equilibrium with the smallest push.

• If a slight increase in temperature causes a greater increase in temperature, this can only occur in the case of an unstable equilibrium. A stable equilibrium, by definition, will not respond with positive feedback. — Cortonin | Talk 05:21, 16 Jan 2005 (UTC)

(William M. Connolley 10:44, 16 Jan 2005 (UTC)) No.

See above, at reference to feedback article. — Cortonin | Talk 23:08, 18 Jan 2005 (UTC)

• Fourthly, the factor-of-twenty stuff is so badly wrong that I've removed it out of hand.

• That factor was documented, try reading the source at the end which documents it. If you disagree, provide a different source and we can establish it as a range. — Cortonin | Talk 05:21, 16 Jan 2005 (UTC)

(William M. Connolley 10:44, 16 Jan 2005 (UTC)) See my comments on GHG

• Fifthly, the Iris stuff was exploded long ago.

• Exploded? According to whom? — Cortonin | Talk 05:21, 16 Jan 2005 (UTC)

(William M. Connolley 10:44, 16 Jan 2005 (UTC)) Anyone paying attention.

I'm going to restore it, as I took great care to write it carefully and document the claims made in that section. You should take equal care to document corrections before rushing to delete every contribution another person makes to one of your pet articles. (I will remove the cultural references if you find cultural background that offensive.) A global warming article which does not discuss the associated feedback mechanisms can hardly be considered complete. — Cortonin | Talk 05:21, 16 Jan 2005 (UTC)

(William M. Connolley 10:44, 16 Jan 2005 (UTC)) Its over at climate change now, where it fits. The GW page was > 45k long with the extra section: it needs stuff moved onto other pages, not added here. The cliamte change page includes a lot of stuff that the GW page isn't complete without, which is why the GW page links to it a lot.

Dispute Resolution RFC, William M. Connolley

I started an RFC regarding user William M. Connolley, located here: Wikipedia:Requests for comment/William M. Connolley. If you are interested, please comment or sign as appropriate. — Cortonin | Talk 12:27, 18 Jan 2005 (UTC)

I had a quick look, but I don't feel I can comment without spending lots more time going through the history. (Except to say that William Connolley's habit of putting his sig at the beginning of his comments is really, really annoying. Rd232 13:17, 18 Jan 2005 (UTC)

However, I note that this topic is covered in Climate change, Global warming, Global warming controversy and Attribution of recent climate change, and looking at Category:Climate change, maybe others. Seems like a lot of duplication to me. The stated split between "climate change" and "anthropogenic climate change" (global warming) doesn't really work IMO, because the discussion ends up covering both anyway. So I would say structure needs clarifying (maybe in Overview section of main article, presumably climate change) and improving. Which might help the ongoing debate which led to RFC.

My suggestion would be

• Climate change becomes very short introduction to entire topic (see various articles in the Category which might be mentioned), without any substantive discussion.
• Global warming becomes the main article for climate change discussion, as this largely about the existence/extent of anthropogenic climate change. Global warming itself focusses on lay summary, and links to daughter articles with more detailed discussion. Somewhere in there (maybe as separate daughter article) should be responses to GW (Kyoto, popular culture, political discussion etc). Global warming controversy should be merged into Global warming. If GW ends up too long (as it probably will), then use daughter article structure appropriately (Effects of global warming would be an obvious one). Rd232 13:17, 18 Jan 2005 (UTC)

On the suggestions for re-arranging

(William M. Connolley 19:15, 18 Jan 2005 (UTC)) GW is already too long. I would oppose merging in GWC... some of it is stuff that was spun out of GW in the first place. GWC at one point contained trashy stuff that didn't belong in GW... it may have been cleaned up by now. See also glossary of climate change if you want ot find other stuff.

If it's "trashy" then it either needs deleting or putting in an article with a useful focus (eg popular/political discussion). The point is not that everything should end up in GW - but I think that should be the logical starting-point, with things spun off from GW (in a logical daughter-article structure) only because of the otherwise excessive length. Rd232 23:14, 18 Jan 2005 (UTC)

How about putting your sig at the end of your comemnts? It's really annoying at the beginning, not least because no-one else does it. Rd232 23:14, 18 Jan 2005 (UTC)

My suggestions for re-arranging are on my user pages. The proposal regarding the structural changes needs to be re-done--it's a little too messy and it still needs work and changes, but at least it's an idea.

• Proposal: User:Benapgar/Proposal
• Sample Global Climate Change page: User:Benapgar/Global_climate_change

—Ben 20:20, 24 Jan 2005 (UTC)

The Introduction

I think the current version is more NPOV and accurate. First, global warming isn't caused exclusively or even primarily by carbon dioxide. So I think it is more accurate to simply say that "greenhouse gasses" are the culprits. Also, the use of absolute terms (e.g. "all climate models" should be avoided unless there is some way of clearly documentating what every single climate model in existence predicts.--JonGwynne 19:17, 19 Jan 2005 (UTC)

I agree with all those changes you made. It makes the introduction feel much more encyclopedic, and a lot less like someone is trying to pull a hand-waving fast one. I like when the introduction tries to tell me what global warming is about, rather than tries to "convince" me of global warming. — Cortonin | Talk 21:39, 19 Jan 2005 (UTC)

(William M. Connolley 22:38, 19 Jan 2005 (UTC)) I've reverted to the Silverback version. The assertion about *all* climate models is accurate. Time and again skeptics have tried to weaken it; time and again I've challenged them to find a model that doesn't show warming; time and again they fail. Come up with the goods or leave it alone.

It is safe to assume that all models predict the warming, of course what matters in science is what one is willing to expose to peer review. If someone were defending a model at odds with the consensus we would hear about it and attempts to resolve the discrepency. The skeptics, however, should not be overwelmed by this, the physics in the current models is fitted to the recent historical data, and there is not yet a peer reviewed way to incorporate the indirect effects that skeptics and the paleo data suggest exist. When the science has progress, the most skeptics expect the models will still show warming, just significally less warming than is currently predicted, and hopefully the models will better match each other and the distribution profiles of the various temperature data sets. As to appearance vs documented or published. The data is published and so are interpretations. While this may appear to be an appeal to "authority", it is a scientific "authority", when these are published they have already passed the reviews of some peers hopefully knowledgable in the previous literature, and most important, they have disclosed their data, analysis and conclusions, so that others can also review, repeat or dispute them. Hopefully, with quality work it is the interpretation more than the facts which will be in dispute, although some "facts" such as temperatures measured by specific instruments may be more a matter of interpretation and analysis than raw data than is assumed. Contributers here should not be afraid that in conceding to the terms "documented" and "published" that they are conceding that things are written in stone. Science doesn't work that way. Perhaps we can find some acceptable qualification to the language, but appearance doesn't get us there.--Silverback 22:59, 19 Jan 2005 (UTC)

No matter how "safe" you personally believe the assumption to be, it is still an assumption. The use of an absolute in this case is inappropriate. until and unless you can demonstrate what all climate models predict. Perhaps we should also discuss the inherently problematic tendency of models to simply project current trends into the future. Go read one of Paul Ehrlich's books on the inevitable future starvations of millions (e.g. "The Population Bomb" to see how reliable this technique is for predicting the future)--JonGwynne 10:55, 20 Jan 2005 (UTC)

I don't know how much assurance you need, but modelers and skeptics have performed reviews and searches of the literature and have not found any, they've attended conferences and communicated via email and the web and haven't found any. I think it would be overly cautious to worry about some Captain Nemo out there incommunicado with a model of his own. Note that "all" is no longer in the opening paragraph anyway. "Most" would just beg the question. Search the article for cosmic, and you will see a discussion of some of the model weaknesses more specific than an analogy to the Population Bomb, there are other discussions on wikipedia as well, but the solar activity/cosmic ray/aerosol/cloud link is the one that seems the most plausible to me.--Silverback 11:17, 20 Jan 2005 (UTC)

How do you know what "modelers and skeptics" have done? Are you one? Incidentally, a 2 second search on Google turned up a 1991 article in "Nature" that talks about how an initial rise in global temperatures can cause an overall cooling effect [6]. Without any modifier, the "all" is implicit. It is important for this article to accurately describe the subject at hand. Since we've estabished at least one model which postits an overall decrease in global temperatures as the result of the greenhouse effect, can we put "most" back?--JonGwynne 13:39, 20 Jan 2005 (UTC)

(William M. Connolley 17:34, 20 Jan 2005 (UTC)) Nice try bu no cigar. I don't see any mention of climate models in there. Have another go.

Removing the "all" is not about "weakening" the statement. Weakening only applies in a confrontational or persuasive sense, and that's clearly outside of the goals of Wikipedia. It's about making the statement more legitimate as a description by removing the sweeping absolutes. I will issue you the same challenge JonGwynne just did: List all climate models. Then show that they all show that result. You should not restore the word "all" until you can document that "all" climate models show this. — Cortonin | Talk 23:40, 19 Jan 2005 (UTC)

I placed a compromise word choice of "observed" instead of "published", as "published" is a needless appeal to authority. When given the choice, we can just document what is, rather than try to justify its strength with rhetorical techniques. — Cortonin | Talk 23:40, 19 Jan 2005 (UTC)

(William M. Connolley 23:07, 19 Jan 2005 (UTC)) BTW, after reverting to your version I removed the qualifier about the extent of human influence on the future trends being uncertain. The magnitude of the trends, yes, thats fair enough (well I wrote it myself), but because of the way the scenarios are constructed there is no "attribution" problem for future trends, because you know the forcing that is going into them. I'm fairly sure that future solar (or volcnaic) forcing, for example, is unknown, and therefore not included, so that doesn't muddy the mix.

I also moved the qualifier about uncertainty of human responsibility for future climate changes outside of the modelling sentence to satisfy your concern about the human responsibility being dictated by the model choice. I instead made the sentence about human responsibility for actual climate change, since I believe that was the initial intent. — Cortonin | Talk 23:40, 19 Jan 2005 (UTC)

I don't see what is added by the qualifier, it a qualifier is needed, it is about the uncertainties of completeness of the physics n the models, and their lack of agreement with each other in particulars. However, I think this is satisfactorially addressed later in the article, which is why the rest of the article is there. We don't need to squeeze all qualifications into the opening paragraph, details can come later.--Silverback 23:55, 19 Jan 2005 (UTC)

Q: What does the clause "If the only variable considered is the emission of greenhouse gases related to human activity" add to the sentence "climate models predict temperatures will increase in the future; however the precise magnitude of these increases is still uncertain."? WTF does it mean? Rd232 12:45, 20 Jan 2005 (UTC)

(William M. Connolley 17:34, 20 Jan 2005 (UTC)) Its a sop the the skeptics. Its not scientifically justified though. I suggest you remove it...

wMC, is correct about it being a "sop", but it makes the point that the model "predictions" are assuming that only one forcing variable changes in the future, so even if technically their models are correct, the predictions may not be, if one of the variables being held constant, such as solar or vulcanic activity change. There is evidence that the solar "constant" has been varying, and that vulcanic activity is essential to understanding the 20th century temperature record.--Silverback 17:52, 20 Jan 2005 (UTC)

It doesn't make this point, at least for me. The models clearly "consider" other variables, even if they hold them constant. It is not a good formulation of the point Silverback explains above. If the point needs making in the intro, it should have its own sentence, and be clear and understandable to someone who doesn't already know what's what. Rd232 12:11, 23 Jan 2005 (UTC)

(William M. Connolley 18:45, 20 Jan 2005 (UTC)) OK, perhaps unnecessary language there. This isn't a good time to have this debate (we should settle the RFC first; starting an edit war here was irresponsible) but just for ref: I'm not going to stir up trouble by trying to remove that qualifier though I'd be happy if someone lese removes it; I don't believe it is justified (any plausible guess at solar forcing is too weak to overcome the GHG forcing).

I did remove it, because the point that it is trying to make it makes very confusingly. But someone put it back. What happened to my suggestion to try to unify the various articles on the topic in a logical structure? Rd232 20:01, 20 Jan 2005 (UTC)

That phrase is a qualifier describing the systems that are being modelled in order to predict temperature increases. It may be a bit awkward to make such a statement in such a small space, but it's necessary if climate model predictions are going to be discussed in the introduction so that we accurately portray the applicability of climate models to prediction. If climate model predictions were removed from the introduction and placed in a section where the qualifiers about climate modelling could be written out in more detail beside them, then that phrase could be written with a little less brevity. — Cortonin | Talk 21:36, 20 Jan 2005 (UTC)

Not only was the phrase a "sop" it was compromise language, I believe largely composed by WMC. The original qualifier was far more explicit, here is my language here:

[7]

I think the compromise language should be restored, because removing it destablizes the compromise, and we start all over again.--Silverback 11:12, 23 Jan 2005 (UTC)

I removed the phrase ", of which the most significant human contribution is from carbon dioxide" from the introduction. Apart from the grammactical problems, there's no indication of the nature of the contribution or the significanc. The link to greenhouse gas will provide plenty of information on the names and significance of the various gasses - by the way, even though both spelling are considered accurate, I use the "three s" version simply because it is more consistent with the other variations on the word "gas" (e.g. gassing, gassed, gasser - no reason for gasses to be the odd one out).--JonGwynne 14:28, 23 Jan 2005 (UTC)

Incidentally, we're still waiting for someone to demonstrate that ALL climate models predict temperature increases. If no one steps up to show this, we're going to have to revisit the "modifier" controversy. Would you prefer "most climite models predict..." or "the majority of climate models..." or how about "commonly referenced climate models predict...", would that be OK?--JonGwynne 14:28, 23 Jan 2005 (UTC)

(William M. Connolley 14:45, 23 Jan 2005 (UTC)) Anytime you can find a GCM to predict cooling, do let us know.

Oh, how almost-clever of you to try to get someone else to do your work. For someone who claims to have a PhD, you don't seem to understand how this is done... you want to make a claim, you'd best be prepared to back it up. You want to say that ALL climate models predict warming? Then you'd better find every single one of them and post links. Since you've obviously seen every single climate model ever created (otherwise, why would you be supporting the claim?), this shouldn't be a problem. Until then, what sort of qualification do you think is appropriate? Take a look at the list above and pick one - or feel free to offer your own suggestion. Also, why did you remove my discussion of the shortcomings of the Mann graph? Since you know so much more about climate science than the rest of us, why not take second to explain why Mann's numbers should still be considered valid when they fail to register the two largest climate shifts in the last millenia? Perhaps you could also explain why tree-ring data is a valid proxy for year-long climate numbers when atmospheric temperature is only one of many factors which affects tree-growth. This should be simple for someone of your professed erudition. Come on, show us ignorant rabble what you've got. You may have been a good student in school, but so far at least, you haven't proven to be a very good teacher.--JonGwynne 15:30, 23 Jan 2005 (UTC)

(William M. Connolley 17:25, 23 Jan 2005 (UTC)) I don't have a PhD. I've said that before, BTW. As to the nonsense above: *you* are making the claim that not-all GCMs show warming. Find one. It should be easy, no?

You don't have a PhD? I beg your pardon. I seem to recall you admonishing someone to refer to you as "Dr. Connolley", but I must have been mistaken - So is it just plain "Mr. Connolley" then? I mean, you're a mathematician, right? You don't practice human or veterinary medicine, do you?--JonGwynne 19:09, 23 Jan 2005 (UTC)

(William M. Connolley 20:42, 23 Jan 2005 (UTC)) I have a doctorate, of course, which is why Dr Connolley is correct.

I stand corrected... For someone who claims to have a doctorate, you don't seem to understand how this is done. If you want to make a claim, you'd best be prepared to back it up. You want to say that ALL climate models predict warming? Then you'd better find every single one of them and post links demonstrating what they show. Since you've obviously seen every single climate model ever created (otherwise, why would you be supporting the claim?), this shouldn't be a problem. Until/unless you do, you'd best decide what sort of qualification you think is appropriate? Is that better?--JonGwynne 21:22, 23 Jan 2005 (UTC)

You are making the claim regarding what all GCMs show. It is up to you to document your claim. You can't claim victory by default. If you can't demostrate what all GCMs show, then you shouldn't be making characterizations as to what they all show, should you? --JonGwynne 19:09, 23 Jan 2005 (UTC)

BTW, I notice you utterly failed to address my points about the Mann data. Do you have anything substantive to say on the subject, or was your removal of the legitimate questions regarding the "hockey stick" curve nothing more than petulant censorship? Explain some things to those of us who don't have the benefit of your prodigious insight into all things climatic... explain to us why the Mann data deserve to be taken seriously when they have been so roundly criticized and, from what it appear to me, pretty well discredited. --JonGwynne 19:09, 23 Jan 2005 (UTC)

(William M. Connolley 20:42, 23 Jan 2005 (UTC)) You'll have to be more polite if you want me to discuss things with you.

(doffs cap and tugs forelock) Oh please your worship, could you please condescend to pass on your great wisdom to those of us who so unfortunately lack it? (was that good enough?) I repeat: Since the Mann data have been so comprehensively criticized, why should we take them seriously?--JonGwynne 21:22, 23 Jan 2005 (UTC)

I also added some discussion of the shortcomings of the Mann numbers.?--JonGwynne 14:28, 23 Jan 2005 (UTC)

I see that WMC et al are still up to their old tricks of trying to stifle disagreement with their particular POV by violating wikipedia policy and unnecessarily reverting changes rather than discussing them or modifying the changes in order to improve the article. Further, in spite of having repeatedly attempted to engage them on these questions, they have simply refused to address them.

Facts:

• There is considerable and legitimate question as to whether the temperature measurements taken are sensitive/accurate enough to definitively establish an increase in temperature.

• The "Mann data" are particularly at issue since they fail to demonstrate well-established climatic variations which occurred in the past.

• Carbon dixoide is not the most significant greenhouse gas either in its effect or in the amount that exists in the atmosphere.

• They still insist on using the absolute statement regarding what they claim "all climate models" show when that have failed to demonstrate how they have established what all climate models show.

Would anyone care to address these issues?

(William M. Connolley 12:41, 25 Jan 2005 (UTC)) Yes indeed:

• Even George Bush accepts the existence and size of the warming. There is room for quibble about the exact size (which is why , in the NPOV form, its given with error bounds) but not the degree of doubt you want.

Here's a tip, you don't want to offer GW Bush's opinion to me if you hope to convince me of anything. As far as I am concerned, Bush's opinions are of little value on much of anything - particularly a subject like this. If we were discussing how to cause a business to fail and how to get taxpayer money to bail it out, or how to use family connections to avoid military service, then I might be interested in his expert opinion. In the meantime, politicians like Bush, Gore and the rest of these trust-fund babies who have demonstrated that they have no idea how the real world works should play in their part of the yard and leave the rest of us alone. I can't for the life of me imagine why you would mention him in this context.

Sorry, to address your point: I have no trouble with the numbers you posted, I have no doubt that they are as accurate as it was possible to make them. But. what's wrong with pointing out that they are not yet conclusive?

• Calling it the "Mann data" shows your POV. It isn't, though the skeptics do their hardest to label it as such. The first paper was MBH - three authors. Subsequent papers with different authors show much the same result. Thre is room for debate on this, and indeed it is debated, on the appropriate pages.

I just used the term because it was one I'd heard, it was short and convenient. I know that there are others responsible for the chart in question. If you have a label you'd prefer, I'll be happy to use it. But that doesn't address the fact that the chart in question fails to show significant climate changes that are known to have happened in the past. That fact would seem to call into question the value of the proxies used to determine climate change. If someone showed me a chart that they claimed would predict the actions of the stock market and, when looking at their past data, the proxies in question failed to show the Great Depression, I would be skeptical of the value of the proxies they used. Wouldn't you? BTW, what POV am I supposed to have. Unlike you, I have no personal or professional state in the global warming theory either way. I would consider myself to be non-partisan and NPOV for that reason.

• CO2 *is* the most signigficant anthro gas; its also the most sig forcing on climate change. Being over-insistent about the role of WV is another piece os skeptic misleading.

That's an interently partisan (POV, if you like) qualification. Whether or not CO_2> is "anthro" or not is irrelevant when discussing it as a greenhouse gas. It is also not entirely true. There are many "non-anthro" sources of CO_2> - decaying vegetation as just one example. If we're talking about greenhouse gasses, we should talk about them all, not just the ones we can partially blame on human activity. Don't you think? My point is that there is an element of the self-flagellatory about certain aspects of the GW debate. There are those who are only seemingly happy when they're talking about how evil and destructive human industry is. See what I mean? As I said before, I am very much in favor of reducing the use of fossil fuels as much as possible. I'd like to see biodiesel used extensively (and, if possible, exclusively) as a fuel for transport and power-generation. That would go a long way toward reducing "anthro" CO_2> generation. Though, there's not much to be done about the few billion tons a year put into the atmosphere as a result of human respiration.  ;-) --JonGwynne 13:42, 25 Jan 2005 (UTC)

Also, I'm not sure what you mean about being "over insistent" about the role of WV. Does WV have a stronger greenhouse effect than CO_2>, or does it not? Is there more WV in the atmosphere than CO_2> or is there not? It seems a pretty clear issue to me.--JonGwynne 13:42, 25 Jan 2005 (UTC)

• This point is simply false, as a read of the article will confirm. The all was taken out long ago, at the suggestion of Silverback - very sensible too. Have you really been doing all these reverts because of an error in your reading of the text?

Without any qualification, the "all" is implicit. Taking out the "all" is irrelevant, it doesn't change the meaning of the statement - it requires qualification. Perhaps you could say something like "All IPCC approved climate models", and then list them. Would that be acceptable?--JonGwynne 13:42, 25 Jan 2005 (UTC)

p.s. I'd like to thank you for being more cooperative and dispensing with the objectionable behavior. Perhaps this is the beginning of a cooperative dynamic. I hope that it can continue. --JonGwynne 13:42, 25 Jan 2005 (UTC)

Scientific consensus vs Consensus science

I have fixed what I consider to be a bogus (and sneaky) link to consensus science disguised as Scientific consensus. There is a distinct difference and the attempt to cause an apparent scientific consensus link lead to a made for the moment consensus science page is flat dishonest. -Vsmith 01:05, 21 Jan 2005 (UTC)

I would say that every link to scientific consensus should be named "scientific consensus", and every link to consensus science should be named "consensus science". The terms refer to different (although related) things, and it would not be correct to point one at the other. The goal here is to provide a clear and complete information source to the reader. — Cortonin | Talk 21:37, 23 Jan 2005 (UTC)

External links to [http://www.climatechange.com.au/]

These links have recently shown up on some of the climate change pages. Is an automated wire service/blog an appropriate link in Wiki articles? —Ben 22:42, 24 Jan 2005 (UTC)

Wikipedia:Requests for comment/JonGwynne

(William M. Connolley 23:23, 24 Jan 2005 (UTC)) You are invited to view Wikipedia:Requests for comment/JonGwynne and comment thereon.

Overall Cleanup

I've spent a lot of time cleaning up the document. I appreciate that not everyone will agree with all of the changes I've made and that's fine but rather than reverting the whole, I would appreciate it if you would make changes from this version so the spelling/grammar/spacing corrections I made can stay put. Thanks.--JonGwynne 13:03, 25 Jan 2005 (UTC)

(William M. Connolley 13:21, 25 Jan 2005 (UTC)) Your version has your POV pushed into it again. If you want to do grammar cleanup, do it on a separate edit, do the "addressing POV" issues separately. "apparent" rise is unacceptable; significant dispute is unacceptable; none of these match the scientific consensus around the issue.

Well, according to your POV, it is POV. That's fine. I hope that we can resolve this without reverting to reverting. --JonGwynne 13:53, 25 Jan 2005 (UTC)

What's wrong with "apparent rise"? The increase hasn't been definitively established - it has been accepted by consensus and that's certainly something. But to say that it is definitely and absolutely rising ignores the legitimate concern over the methods used to establish the claim. Put another way, saying something is "apparently" true, doesn't change the fact. I could say that you "apparently" have a doctorate, or that you claim to have a doctorate. These statements would be true. I haven't personally validated your qualifications so I don't know for certain whether you have a doctorate or not. When I qualify my statements, I'm not attempting to diminish your credentials, but rather pointing to my own uncertainty. See the difference? --JonGwynne 13:53, 25 Jan 2005 (UTC)

What's wrong with "significant dispute"? There is a dispute and it is significant. That seems pretty clear. Whether that statement "matches" the consensus is beside the point. Those with the dispute are not part of the consensus.--JonGwynne 13:53, 25 Jan 2005 (UTC)

I think you are overstating or mistating what the disputes are. Today most skeptics accept that warming is most likely occurring, and although they may have residual doubts about how conclusive the data and analyses are, and still see problems and incompleteness in them, they are not countering the weight of the evidence with publications. The skeptical focus now is on the mismatch between the models with each other and the temperature distribution data and the models oversized predictions compared with what one would expect from the published paleo data and analyses. So your version is not consistent even with skeptics emphasis, but rather seems to be insisting unreasonably on uncertainty for uncertainty's sake, where there isn't much published research to hang your hat on. One can always say "well it ain't proven", but while trivially true, it doesn't have much persuasive power, especially when it is used to insist on overqualifying so many statements.--Silverback 14:14, 25 Jan 2005 (UTC)

Follow-up on the major issues, JonGwynne, there is already a lot of solar variation in the article so your major addition is duplicative, perhaps you don't recognize that the cosmic ray stuff is a proposed indirect mechanism? Your other addition about the CO2 from the large increase in the human population states a largely insignificant contribution when compared not only to the fossil fuel sources but also insignificant when compared to the methane from cattle. It is not worth mentioning.--Silverback 15:17, 25 Jan 2005 (UTC)

The last papers I read on sea level rise referred to pretty high systematic uncertainties, and to a pretty wide range in values measured, depending on what land mass they're measured from. So I think JonGwynne's edit to "appear to be" rising is a bit more fair to the content of the literature. — Cortonin | Talk 19:27, 25 Jan 2005 (UTC)

In addition, the line "There are no known climatologists supporting this viewpoint", even if true, is a crappy phrase to put in an encyclopedia. If you want to have a line like that with a sweeping generalization, then you should document it. So in order to keep it, please list all known climatologists, and beside it place their views. (Since claims like that should always be documented.) — Cortonin | Talk 19:27, 25 Jan 2005 (UTC)

Also, the line "The majority of scientists agree that important climate processes are incorrectly accounted for by the climate models but don't think that better models would change the conclusion." is not sufficiently documented. JonGwynne's change of this to refer specifically to the IPCC is more correct. I don't recall anyone ever surveying physicists, chemists, or biologists about their opinions on climate modelling, so lets not make undocumented claims about the majority of scientists. There are also some climatologists who have spoken out saying they don't think the IPCC represents the consensus of all climatologists, so lets avoid such debates by simply making such things "According to the IPCC, the majority of climatologists", or something of the sort. — Cortonin | Talk 19:27, 25 Jan 2005 (UTC)

And as for "All models show that the warming occurring from approximately 1975 to 2000 is largely anthropogenic." Are we still debating this??? List all climate models so you can document this claim. — Cortonin | Talk 19:27, 25 Jan 2005 (UTC)

"Some skeptics would claim that the warming trend itself is not valid, and therefore does not need any explanation." Jon's elimination of the word "would" is correct. This is not a matter of POV, it's a matter of accuracy. It's not that they "would" do it, they have. They've even published papers on it. — Cortonin | Talk 19:27, 25 Jan 2005 (UTC)

"Skeptics have been unable to produce a model of the climate that does not predict that temperatures will increase in the future." How about, "The sun stops shining". Seriously, sweeping generalities are not useful. — Cortonin | Talk 19:27, 25 Jan 2005 (UTC)

And regarding the temperature since the ice age, I think for accuracy's sake, "relatively stable" is more useful of a term than "quite stable". After all, it's pretty damn cold outside today, but it's no ice age. (Thus, "relatively stable".) — Cortonin | Talk 19:27, 25 Jan 2005 (UTC)

And lastly, "and about half the minor ones, I would dispute" If you dispute half the changes, then only revert half the changes!!! This attitude of reverting everything if you can find something you disagree with is completely counter to the way other wikipedia articles are managed, and it makes the climate related articles extremely annoying to work with. Please follow wiki policy and assume good faith. If someone is going to take time out of their day to voluntarilly read an article and think about changes that might improve it, then you should CERTAINLY take time to consider each change before you undo all of that work. This policy of "glance at it, see if there's anything I don't like, and then revert everything" is instead a sweeping assumption of bad faith, and it's very counterproductive. Try to make an effort here to respect other people's contributions and the time they put into them. — Cortonin | Talk 19:27, 25 Jan 2005 (UTC)

Sorry, reverting is the way go with such extensive changes intermixed with POV additions. The language corrections that I agree with are not that remarkable and rather than laboriously edit his version which is more divergent from the final product, it would be easier to just proof read the "original" language myself. You should also bear in mind that some of the awkward language is by "design", since it is not the result single authorship, but a compromise, resulting in point and counterpoint. It doesn't make for beautiful literature, but it is the way wiki is done. An understanding of the history, from having participated in the creation, gives one knowledge of which changes that might seem more concise would actually disturb the stability of a compromise article.--Silverback 22:25, 25 Jan 2005 (UTC)

Reverting may be the "easy" way to go, but it is not the wiki-way to go. Here we assume good faith edits, and we work with contributions and other contributers, not to try to oppose them. — Cortonin | Talk 10:39, 26 Jan 2005 (UTC)

I certainly agree. However, good faith edits do not imply good edits. JonGwynne built up such a large difference in his version through persistence, not good faith cooperation.--Silverback 10:45, 26 Jan 2005 (UTC)

CO₂ POV

Why the insistence on claming that CO₂ is "the most significant"? First of all, it isn't. Water vapor is the most significant greenhouse gas. CO₂ emissions can't even be eclusively attributed to human activities (like, for example, CFCs can).

What's the point of mentioning human activities with regard to CO₂?--JonGwynne 18:38, 27 Jan 2005 (UTC)

Your proposed statement is wrong, because water vapor is the most significant greenhouse gas, humans just make their most significant contribution via CO2. The text you are trying to correct does not imply that humans are the sole source of CO2.--Silverback 18:50, 27 Jan 2005 (UTC)

But you have two problems here. The first is that, in this context, the meaning of "significant" is far from clear. Does it mean that CO₂ has the strongest greenhouse effect of all GHG? No, we've already established that. Does it have the strongest greenhouse effect of all the anthropogenic GHGs? No again. It is, in fact, one of the weakest. Is it the most toxic? Certainly not. Is it the most persistent? Nope. So, I ask again, Why? should it be considered the "most significant"?--JonGwynne 21:43, 27 Jan 2005 (UTC)

(William M. Connolley 22:15, 27 Jan 2005 (UTC)) Its the most significant for the obvious reason: it makes the largest contribution to the GHG of all human-emitted gases. And the WV stuff is irrelevant, of course. Stop trying to minimise the role of CO2. WV is reactive, CO2 is active.

WV has how many times the strength of CO₂? There's certainly a lot more of it in the atmosphere. I'm not trying to minimize anything, I'm simply looking for some perspective. How about talking about the tendency of the oceans to absorb CO₂? If you waved a magic wand and all anthropogenic CO₂ generation stopped, the CO₂ levels in the atmosphere wouldn't just stabilize, they'd start to drop precipitously. Also, how do you explain the cooling trend in the middle of the last century in spite of continually rising CO₂ levels? Seems to me that CO₂ isn't the key factor in global temperature. Yet, you seem to want to suggest that it is. Can we start by clarifying that question? Do you want to suggest that CO₂ is the key factor in determining global temperature?

No. But we do want to suggest it is the key human contribution to changes in the greenhouse effect. The human contribution is not the only contribution to CO2 and methane (attributing cattle methane to humans), but the change in these gas levels is measurable and the human contribution best explains recent changes, and this is net of any ocean absorption. The size of the impact of that change is controversial. Keep in mind that water vapor has a much shorter life in the atmosphere, so short that its local values are highly variable. A global human impact that is less reactive like CO2 will, will likely have a greater global influence on both temperature and water vapor itself, than local human water vapor emissions. Understaning the direction and nature of this feedback through water vapor and its contribution to the greenhouse effect, aerosolsa nd clouds is a central area of research.--Silverback 02:18, 28 Jan 2005 (UTC)

Some questions:

• OK, its the key human contribution, but where does it sit in the overall picture? What percentage of the CO₂ increase is attributable to human activity? What percentage to natural sources (e.g. seismic activity, organic decomposition)?
• When you say "human contribution best explains recent changes", you mean for the CO₂ level only, right? Which brings me to:

Wrong, I also mean for methane levels, where there is much natural variation, a human signal has been teased out.--Silverback 03:56, 28 Jan 2005 (UTC)

• What portion of the observed/projected warming is due to that portion of CO₂ generated by the burning of fossil fuels?

Fossil fuel CO2 is indistiguishable from other CO2. The net contribution to warming is the controversy, the models disagree with each other, the temperature distribution data and the paleo inferences.--Silverback 03:56, 28 Jan 2005 (UTC)

• Even though water vapor "cycles through" the atmospher more rapidly than CO₂, there still is a great deal more of it in the air at any given time, right? Regardless of how much of that WV was actually generated by human activity...

Yes. --Silverback

I think these issues shoud be adressed, don't you?

Some cannot be addressed now and must await further research, if you will carefully review the articles (not just this one, so that duplication is avoided) you will find most of the current state of the science including sides of controversies are represented, perhaps in ways you have difficulty understanding, since the particular point at issue here, took you quite some time.--Silverback 03:56, 28 Jan 2005 (UTC)

It's usually not productive to subtly imply that other contributors "have difficulty understanding" or are slow. It's possible for a person to be intelligent and yet just discussing something out of their expertise. Let's try to keep the commentary civil. — Cortonin | Talk 05:20, 28 Jan 2005 (UTC)

I've got to say that was about the most circumlocutious way of calling someone "stupid" that I've ever seen... and, yes, Cortonin, I agree.--JonGwynne 13:29, 28 Jan 2005 (UTC)

Perhaps it took you some time, not because you were stupid, but because you weren't carefull, as I highlighted in my statement, although as Cortonin pointed out, it may because you are out of your expertise, which should, of course, call for more care. Some of your comments are quite glib and simplistically obvious, which would also indicate lack of serious application. --Silverback 09:31, 29 Jan 2005 (UTC)

I think it's okay to state that the most significant human contributions to greenhouse gases is the contribution of CO2, but in doing so we just have to be careful not to inadvertently imply that CO2 is the most significant human contribution to global temperature (since that is not definitively established), that CO2 is the most significant greenhouse gas (since almost everyone agrees it isn't), or that human contributions are the dominant factor in CO2 levels (since there seem to be wide discrepancies between predicted and actual CO2 levels). I don't believe anyone has been trying to imply either of these things, but keep those things in your mind while rewording that section to make sure none of them are inadvertently implied. — Cortonin | Talk 05:20, 28 Jan 2005 (UTC)

The problem I have is with the word "significant". In this context is is effectively meaningless. Let's try to find something that is more clear and informative. Is that OK?--JonGwynne 13:29, 28 Jan 2005 (UTC)

It is important that the article discuss the ratios of anthropormorphic CO2 and 'natural' CO2 and the use/misuse of proxy data for pre-Industrial Revolution values at a baseline. -Denise Norris 07:24, Jan 28, 2005 (UTC)

Argh, would you people read the paragraph? The preceding sentence discusses how we are trying to understand the influence of humans on global warming, through greenhouse gases - and CO2 is the main gas introduced by humans. I would MUCH RATHER we not say at all that CO2 is the main anthropogenic gas in that sentence than mangle the introductory paragraph by introducing chains of poorly-linked sentences. This discussion can be very nicely fleshed out in a subsequent paragraph, it does NOT need to happen in that one sentence. Shall we turn the whole article into one giant run-on? Graft 15:52, 28 Jan 2005 (UTC)

1000 of NH Temp Graph (Hockey Stick)

In light of the serious questions about statistical process in the work of Mann, et al. brought to light by McIntyre & McKitrick, I think that placing a diagram of the hockey stick without at least a disclaimer is highly POV.

Absoutely, I've been trying to get some sort of qualification in for quite some time, but it is invariably shot down by you-know-who. To present the "hockey stick" graph as the absolute and unqualified truth is irresponsible. --JonGwynne 13:29, 28 Jan 2005 (UTC)

Representing anything in science at an absolute and unqualifed truth is not only irresponsible, but foolhardy as well. History is replete with scholars who have had to eat their words. Imagine the damage to the reputations of the scientists who claimed that traveling fast would be injurious to people and then were proven wrong by the advent of the steam locomotive?

A good scientist is someone who always ready to admit that he might have gotten it all wrong, a second-rater is someone who is sure they know the right answer all the time. --Denise Norris 14:12, Jan 28, 2005 (UTC)

Be careful. While you're exactly correct there with both paragraphs, statements like that will get you eaten around here.  :) Welcome. — Cortonin | Talk 15:18, 28 Jan 2005 (UTC)

I have been flamed before and I am sure I will be flamed again! ;-) --Denise Norris 15:35, Jan 28, 2005 (UTC)

McIntyre & McKitrick identified non-disclosed statistical processing that amplified the proxy data of the Brislecone Pines in such a way that would produce a similar hockey stick with even random noise.

The work McIntyre & McKitrick has been accepted for publication in Geophysical Research Letters (American Geophysical Union). A pre-publication version of the article is available at http://www.climate2003.com/.

Mann, et al. are disagreeing as expected and have set up a counter point at http://www.realclimate.org/.

Personally, I am in favor of removing graph entirely until there is a resolution concerning the approach used by Mann. Furthermore, the article does not even reference it and without clarification, the graph is misleading to the layman. --Denise Norris 08:46, Jan 28, 2005 (UTC)

(William M. Connolley 09:28, 28 Jan 2005 (UTC)) How about replacing it with one of the many others that show the same thing? Why don't you do some howwork and find a PD one from the IPCC site?

Ummm... Perhaps I was not clear. The work of McIntyre & McKitrick shows that the hockey stick is invalid statistically. How about just removing it or explaining it? Why don't you read M&M's work and let me know your opinion? --Denise Norris 09:48, Jan 28, 2005 (UTC)

(William M. Connolley 09:56, 28 Jan 2005 (UTC)) Perhaps you missed my point. There are other reconstructions which show much the same thing. Oh, and while I'm here, I think MBH are correct and M&M are wrong. M&M's work does *not* invalidate MBH.

Well, your POV is immaterial here as would be any of your orginal work. --Denise Norris 10:08, Jan 28, 2005 (UTC)

(William M. Connolley 10:23, 28 Jan 2005 (UTC)) And neither is your POV. MM have been assiduous in trying to attack MBH but its not clear why the rest of us should believe them. One paper - not even yet published - doesn't overturn a whole lot of other work just by itself, until people have had a chance to read it, assess it, and either accept or reject it.

M&M's work was orginally published in 2003. Perhaps you need to update yourself on body of work? You know... do your homework.... --Denise Norris 11:42, Jan 28, 2005 (UTC)

You have to be very careful when you criticize or contradict WMC, he's very sensitive about it. For him it seems to be the equivalent of heresy and he behaves towards those who challege the orthodox (i.e. IPCC) view as heretics. If you're not careful, you'll find yourself the subect of an RFC.--JonGwynne 13:29, 28 Jan 2005 (UTC)

(William M. Connolley 12:59, 28 Jan 2005 (UTC)) Indeed it was. But M&M have a history of making mistakes... degrees and radians, that kind of thing... do your homework (no, thats asking too much, I'll do it for you: http://cgi.cse.unsw.edu.au/~lambert/cgi-bin/blog/science/McKitrick/)

(William M. Connolley 10:23, 28 Jan 2005 (UTC)) I've just realised that MM05 isn't even published. Wiki is here to reflect the mainstream view, whilst giving space to minor views. There is no way that a paper not even published can affect that.

WIki is here to provide NPOV articles, but it is clear you have an agenda to insert your POV into the process. --Denise Norris 11:42, Jan 28, 2005 (UTC)

(William M. Connolley 12:59, 28 Jan 2005 (UTC)) Trying to find a NPOV for the climate articles is very hard, as most people that care to contribute seem to have rather strong opinions. One way is to keep it focussed on the *published* science, which seems like a rather good idea. When MM05 gets published, then its worth talking about.

Presenting only the hockey stick graph without a discussion is hardly neutral. I don't care if M&M, per se, is discussed, but there should a mention that there are challenges to the MBH work if only so the reader has the opportunity to form an informed opinion.

If the hockey stick graph is on the article, it needs to be discussed in a neutral manner and that it's accuracy not only disputed, buts fails to even indicate that the medieval climatic optimum (700 AD to 1300 AD) or the Little Ice Age (Maunder Minimum). When I was last studying Atmospheric Sciences (granted, it was a long time ago that I received my degree), the Maunder Minimum and the associated years without a summer were pretty much accepted facts. Of course back then, many of the scare mongers were busy getting grants to prove were entering another Ice Age! Or that we would all be starving by the year 2000, etc...

(William M. Connolley 20:33, 31 Jan 2005 (UTC)) That too is wrong. See http://www.wmconnolley.org.uk/sci/iceage/ for details.

All I am advocating is that either the graph has to go or a brief discussion of the implications and controversy around the graph has to be added in order to create a NPOV. My use of M&M was an example that there is controversy - it was not an endorsement of their work.

Stick to debating that point for the moment. --Denise Norris 14:12, Jan 28, 2005 (UTC)

Now count to ten and re-read what I wrote before responding. --Denise Norris 14:12, Jan 28, 2005 (UTC)

Well done. We've been trying to make this point to WMC for some time now.--JonGwynne 14:54, 28 Jan 2005 (UTC)

Well, in the fifteen minutes I've been reading about this debate (I'll read more later I promise) I hardly see the justification for minimizing the graph. In the end one must ask whether M&M are correct, in their analysis of Mann et al, and in their larger point that late-20th century warming is not anomalous. Mann defends his original paper reasonably enough, on the first point, and on the second, Mann is one of scads of papers using different methods to demonstrate that late-20th century warming is unprecedented. So... what discussion do you have in mind? To what purpose? Graft 16:10, 28 Jan 2005 (UTC)

Whether M&M are correct or not is not the issue. The real core problem is if we trust the MBH98 results – often portrayed as the famous hockey stick currently under discussion.

The reason the validity of MBH98 is so important is not what it tells us about the last 100 or so years, but what it tries to tell us about the previous eight or nine centuries.

MBH98 describes relatively benign climatic conditions until 1950 for North America until ‘global warming’ kicks in, leading some to believe that there is a correlation to global warming with expansion of industrialization at the end of World War 2 – This included a switch from coal to petroleum as the primary source of energy. However, if MBH98 is incorrect and there is greater climate variability then shown on the hockey stick, the current trend of global warming may just be climatic change and the entire human race is along for the ride, like it or not.

The consensus for global warming starts to fall apart when we move out of the 1880 to 1950 range. Urban heat islands distort the surface temperature dataset (whose monitoring stations do not represent nearly as much of the ‘surface’ as one could hope) and even appears to influence the Near-Surface dataset.

More importantly, there is a great deal on dissent on the paleoclimatic side of things. The MBH98 data is the accepted model for historical climate and is used to justify Kyoto when selling the Treaty to the public.

Depending on the revert of the minute, there is no discussion of the disagreements with the graph leading the lay reader to assume that it is accepted by all scientists. So, either we need to point out to the reader that there is dissent on the representation of reality supplied by MBH98 and direct them to the proper page for additional information. To knowing exclude such information from the reader is just pushing a POV. --Denise Norris 17:33, Jan 28, 2005 (UTC)

I had added a more detailed discussion of the Hockey Stick figure and its possible mismatch with MWP and LIA. JonGwynne deleted most of it. Before I get into an edit war: Why? --Stephan Schulz 17:14, 28 Jan 2005 (UTC)

How about we come to a consensus here on the talk page before editing and reverting repeatly on the article? Give it a few days so all have a chance to be heard. The MBH98 results are the very heart of the arguement for man-made global warming and that belief is near and dear to many.

Well, as far as I can tell, my text was purely descriptive (both of the graph and its interpretation) and should not be contentious. I'm offering it as a starting point:

Over the past 20,000 years the dominant temperature signal has been the end of the last ice age, approximately 12,000 years ago [8]. Since then the temperature has been relatively stable, though with various (possibly local) fluctuations, e.g. Medieval Warm Period or Little Ice Age. The graph "10 centuries of NH temperature" shows a reconstruction of average temperature in the northern hemisphere, computed from proxy data (e.g. tree rings and ice core analysis) and, for recent times, actual temperature measurements. While it shows a slighly warmer climate in medieval time, followed by drop in temperature until the mid 19th century, the effect is not very pronounced. This leads some people to question the validiy of the reconstruction, while others consider it as evidence that the Medieval Warm Period and the Little Ice Age were more localized than previously assumed.

At least the description of what the graph shows (reconstructed northern hemisphere temperatures, based on proxies) should be somewhere. --Stephan Schulz 18:23, 28 Jan 2005 (UTC)

The basic issue here is not if MBH98 is correct or incorrect, but do we add text stating it is disputed. Let's not end up debating MBH98 itself. --Denise Norris 17:33, Jan 28, 2005 (UTC)

I'm sure we could debate to great length about whether MBH98 is a sensible result or not, and that would be an interesting debate to have somewhere else. But you're right that the fact remains that the statistics used to generate it were legitimately questioned and are still legitimately under dispute. This definitely needs to be mentioned when that plot is going to be used. Let the reader know and let the reader decide. — Cortonin | Talk 19:02, 28 Jan 2005 (UTC)

There's another issue which hasn't been brought up, and that's the question of the error bars. If you look at the discussion here, you'll see that the original version had much larger error bars, perhaps indicating the systematic uncertainties in the early temperatures, while the later one, currently in use, seems to have been generated by a wikipedian who discarded those error bars in favor of generating new ones simply using statistical error. I believe this may be artificially overstating the certainty and accuracy of the early temperatures. — Cortonin | Talk 19:02, 28 Jan 2005 (UTC)

(William M. Connolley 18:09, 28 Jan 2005 (UTC)) Do you think you might want to address my point that several other non-MBH records show pretty much the same thing? You are aware of that, aren't you?

Yep, but that was not the purpose of my comment here. But if you want to discuss it on the Temperature record of the past 1000 years page, I will be glad to have a reasonable and polite discussion. --D. Norris 18:20, Jan 28, 2005 (UTC)

If the entire source of the dispute is one crappy paper by M&M, to which Mann has responded (although obviously not in print yet), I don't agree that the debate needs to be highlighted. If you have a more definitive dispute you want to describe, I'm unclear as of yet on what that is. Graft 18:26, 28 Jan 2005 (UTC)

Ummmm.... No, it is more than one paper. It is more than just one author. Dr. Hans von Stoch comes to mind as well. BTW, have you read M&M to see for yourself if it is truly a 'crappy' paper?

Oh yes, one more thing... Mann responded and M&M responded, etc... which is how science get done. --D. Norris 18:37, Jan 28, 2005 (UTC)

I think that there is going to be a storm of controversity when MM05 is published in February.

The Financial Post:

Breaking the Hockey Stick - Part 1

http://www.canada.com/components/printstory/printstory4.aspx?id=108c0400-4e71-4c55-a279-dd43aed1f224

The lone Gaspe cedar - Part II

http://www.canada.com/components/printstory/printstory4.aspx?id=052554eb-ebdb-483a-8f28-c4ce19458973

Lets move further discussion on this to Talk:Temperature_record_of_the_past_1000_years under MM05 heading (forgot to sign --D. Norris 16:52, Jan 29, 2005 (UTC))

Unsigned one. When this is published will be the time to get this on one of the main pages. It sounds the like these authors have good responses to the issues raised by the defenders of the original results.--Silverback 16:15, 29 Jan 2005 (UTC)

Agreed... that is why I suggested the talk page for now. --D. Norris 16:52, Jan 29, 2005 (UTC)

Also, thanx for your references above. It looks like the authors of other studies will come under great pressure to make their data available and show that they are not subject to the same errors. To the extent that the hockey stick on this page is dependent on the Mann data, it may have to go. Since it is probably just one component, handling it properly will be problematic. It sounds like what was thought to be the best hockeystick paper has all but fallen. Weaker ones will have to take up the slack if they can withstand the fire.--Silverback 18:01, 29 Jan 2005 (UTC)

See my blog [9] for the MM05 paper, articles about the paper, and my comments. Maybe guys, we should really show our patience and only post the text about MM05 once it's officially published. William can enjoy the last weeks of decent life before his hockey team is recognized as the authors of the most costly scientific fraud in the history of the humankind. Their future is about as bright as the future of Saddam Hussein after he was found in the spider hole. ;-) You know, there may be a huge snowstorm of the people who will show that the rest of the papers supporting global warming is (probably) fraud, too. --Lumidek 21:06, 29 Jan 2005 (UTC)

I assume that version is not the final paper, it will be interesting to see if they incorporate further responses to points already raised by Mann, et al. I would not call the Mann paper a fraud, perhaps a mistake blinded by bias, but instead, unfortunately, it should probably be praised for at least providing enough detail for a critical analysis. It is embarrassing that the raw data is not available for some of the other papers. Open corrections such as this are the way science is supposed to work, and should improve the quality and openness of future work.--Silverback 06:18, 30 Jan 2005 (UTC)

Dear Silverback, I mostly agree with you. But the reasons why I tend to think that this deserves the label "fraud" are the following: Mann et al. have had the directory called "CENSORED" in which they most likely obtained the graph without the hockey stick shape, properly. But they deliberately continued to make various modifications until the shape is obtained. The "standardization" of the period 1900-1980 that they did is perfectly correlated with the "blade" of the hockey stick. I just don't believe that they did not get the idea that the different shape for 1900-1980 and their different treatment of 1900-1980 are uncorrelated. My experience does not suggest that these people are examples of scientific integrity. The money for the research of climate is certainly used highly inefficiently. It's just amazing that for these roughly billions of dollars, they can't make a controllable treatment of this important data. I am sure that a motivated and smart statistician could verify all these statistically based papers for 1/1,000 of the amounts that are normally spent. --Lumidek 17:21, 30 Jan 2005 (UTC)

I agree that the "CENSORED" label is suspicious, and I hope there is a reasonable explanation for this. If it is part of an evidence trail of fraud, what prevented them from deleting it, rather than giving it an attention attracting name? If they are innocent, I hope they have the sense to openly acknowledge mistakes and limitations, and explain for the betterment of science where they went wrong.--Silverback 18:27, 30 Jan 2005 (UTC)

US Record

This is absolutely relevant to the discussion of temperature trends. Even though WMC apparently doesn't like the data because they don't agree with his pre-concieved views, the fact remains that there is no other collection of actual temperature data over such a large geographical area for as long a duration. The reason for this should be fairly obvious: during the time in question, the US hasn't been subject to any world wars, revolutions or any of the other things that make meticulous science and record-keeping impossible. If someone has data from another country or region they'd like to contribute, let's have that posted as well. But the idea that the US record should be removed is simple unacceptable.

There is already language in the article which makes it clear that records for the US don't necessarily reflect the state of the entire globe. What else is needed?--JonGwynne 19:05, 28 Jan 2005 (UTC)

I have no strong opinion on wether the US temperatures should be in or out. But please, whenever someone restores them, please restore a correct version. The graph displayed shows only the temperature record for the lower 48 states, or about 30% of North America, not "most of it". Check the source! --Stephan Schulz 02:23, 29 Jan 2005 (UTC)

Regardless of why Dr Connoll(E)y removed the comment, lets consider the US surface temperature for a moment.

Two major issues cloud the surface record:

1) Urban Heat Island Effect (UHIE) (http://www.nasa.gov/centers/goddard/news/topstory/2004/0801uhigreen.html) and;

2) there are concerns about the coverage and duration of the collecting stations(http://www.giss.nasa.gov/data/update/gistemp/).

If we wish to include the GISTEMP dataset, there needs to be a similar disclaimer as the 1000 yr record.

Perhaps a more interesting group of datasets is the Near Surface, Sea Surface, Balloon and Satellite. I know someone is going to jump on my case for posting a link from this site: http://www.junkscience.com/MSU_Temps/CompareDatasets.gif --D. Norris 19:41, Jan 28, 2005 (UTC)

(William M. Connolley 11:03, 29 Jan 2005 (UTC)) Junkscience is junk, of course. I removed the US record (and will again) because there is no reason to put in this particular part of the world. The reason the skeptics like it, of course, is because it shows lower than average warming. So we could put in somewhere that shows higher than average, but that would make no more sense. *If* the article developes a section on regional variations of trends, then it would make sense.

You are right, Bill! Localized trends have no place in a global warming article. So lets keep it out. By the same token, we need to remove the 1000yr Northern Hemisphere graph and all references to MBH98 as that is not a global warming trend either. Good point! Glad to have a expert like you on board! --D. Norris 12:59, Jan 29, 2005 (UTC)

It IS a good point - are you seriously suggesting that the US record is on the same par as a hemisphere-wide summary? Can you be less snide, as well? Graft 17:36, 29 Jan 2005 (UTC)

That was sarcasm, sorry you missed it. --D. Norris 17:41, Jan 29, 2005 (UTC)

(William M. Connolley 21:22, 29 Jan 2005 (UTC)) Ah, but in that case you shouldn't keep removing the NH record from the page. Your put in an edit comment: Pls, it is important to be consistant... most of the data is really US data anyhow...). The second part is wrong. The first part is correct, but misapplied. We have essentially global data since say 1860: so there is no reason to show one regional record. But we don't have good global data for the last 1000 years, so the NH record makes sense. Please stop this nonsense.

How about we try for a compromise? You stop removing the US record because it disagrees with your POV and amplify the importance of it demonstating the variablity of the GIS record by specific locale. This is the least of the issues you should be worrying about defending. MM05 is coming! --D. Norris 21:38, Jan 29, 2005 (UTC)

(William M. Connolley 12:48, 30 Jan 2005 (UTC)) How about you write a nice informative article about regional variations, if you're so interested in them? MM05 appears to be a political stunt, judging from the reations of the various skeptics here.

??? Sorry, but do you realize how insane that last sentence sounds? — Cortonin | Talk 18:31, 30 Jan 2005 (UTC)

(William M. Connolley 19:52, 30 Jan 2005 (UTC)) Its pretty clear from the comments of the skeptics that they are judging the paper on their prejudices, not its text. I very much doubt that they have read it, or understood it.

I subscribe to Cortonin's definition of insanity. For me it just sounds absolutely incredible that William M. Connolley, as he explains on his talk page, has not read the paper (MM05) yet. I've read not only the paper, but also all articles that comment on this paper, even though it is not my field. Is William really trying to picture himself as an expert, even though he judges the paper by "the reations [sic] of the various skeptics here"? (William M. Connolley 09:52, 31 Jan 2005 (UTC) comment edited for civility) Do you really believe that even after February, your politicized science will continue as "usual"? (William M. Connolley 09:52, 31 Jan 2005 (UTC) ditto) The paper MM05 is a technically excellent paper - something that you and your Mannly friends will never be able to write. --Lumidek 00:53, 31 Jan 2005 (UTC)

(William M. Connolley 09:52, 31 Jan 2005 (UTC)) MM05 hasn't been published, but that didn't stop you putting it into the pages. I don't like science by press release, which is what MM are doing. MM haven't realised how little any of what they are doing matters, even in the unlikely event of their being correct.

I think its main impact will be to weaken the fear mongering by putting the current warming in historical perspective, perhaps climatologists who try to reproduce paleo and modern climates with the same model may also have an easier time matching correct data, than incorrect data. Also, other results will now be discounted if their data is not available for reanalysis.--Silverback 15:20, 31 Jan 2005 (UTC)

(William M. Connolley 15:24, 31 Jan 2005 (UTC)) Well, very nice, lets wait till its published (or rather, I will; it really isn't very important). In the meantime, what about the inclusion (or as I'd prefer, exclusion) of the US record?

I don't see a reason to have a revert war here, if there is another prominent climate page where it would be acceptable to you. I personally have not felt that strongly either way however. I think the NH data will come under serious question when the MM05 paper is published, especially since some of the other studies have been unable to allow their analysis to be reproduced due shoddy care of the raw data.--Silverback 15:44, 31 Jan 2005 (UTC)

(William M. Connolley 16:40, 31 Jan 2005 (UTC)) This would seem to be where we start to diverge. However, hopefully we can do so in a civilised way. I think its a shame that the people who seem so very interested in regional change spend their time inserting inappropriate pictures and text here rather than starting a proper page about it.

It would of course be wrong to make global arguments on the basis of the US record (which I hope no one is trying to do, although JonGwynne seems to be leaning in that direction in the comment that started this section); it IS illustrative of regional variation, but there's no particular reason to have an extensive discussion of it here, unless it is the basis for a prominent critique of global averages (which I think is being alleged). Is this the case? If so, who advances this critique and is it seriously considered? If not, why discuss the US record in particular here? Would D. Norris or J. Gwynne like to weigh in? Graft 17:15, 31 Jan 2005 (UTC)

The US data is a significant part of the cited northern hemisphere data, since historically much of central and east asia has poor coverage and wars have disrupted European data. Given the significance of the upcoming publication, perhaps there will be an acompanying editorial that helps put it in perspective, including the extent to which the NH data and the IPCC analysis depends upon it and should be reassessed. Any quotes there and from the authors might be of more assistance than asking readers to interpret the US data themselves.--Silverback 18:27, 31 Jan 2005 (UTC)

The US record was in the article until Dr C. unilaterally deleted it without any discussion. I restored and modified it as an example of both the regional variations (to address some of Dr C's objections and to demostrate the difficulties getting a surface trend that accurately reflects reality. My feeling is until there is at least some discussion and the opportunity for all to consider the proposed removal of the US Temp record, it should stay in it's current form or even revert further back and remove my additional text. --D. Norris 17:41, Jan 31, 2005 (UTC)

(William M. Connolley 18:14, 31 Jan 2005 (UTC)) There is plenty of discussion here, so don't pretend I removed it without discussion. It a regional record, not a global one. There is no reason to present it here.

Well actually, Graft, the idea that the U.S. data is more representative is actually put forward, and reasonably well argued. See [10] for an example (starting on page 3). He puts forth that care has been taken with the U.S. data set to avoid phenomena such as the urban heat island effect (known to have yielded a temperature rise which exceeds the observed global temperature rise), but that the rest of the global data has not had similar care taken. He also argues that this indicates there may not actually be any net warming which has occurred, but only statistically insignificant fluctuations, since the largest data set which carefully accounts for systematic effects shows no significant rise. He also argues that satellite temperature data corresponds to the U.S. temperature data, but does not correspond to the global temperature data, indicating that accuracy may be higher for the U.S. data set. Whether or not we agree with this as Wiki editors, it IS a reasoned and published scientific argument, it DOES point to the shortcomings of our temperature measurements (and the fact that we can't go back and remeasure past measurement errors), and it not only warrants inclusion here, but also says we shouldn't go censoring out a perfectly good U.S. data set. — Cortonin | Talk 18:38, 31 Jan 2005 (UTC)

(William M. Connolley 19:03, 31 Jan 2005 (UTC)) The paper you so frequently cite is from 1990 - 15 years ago. In terms of observations and theory, thats a long time. Its obsolete; it was a minority (well, one person) view even then.

I was going to point out that the TAR comments on urban heat islands extensively and specifies their (negligible) contribution, but WMC already seems to have removed it from the article. Does anyone argue against that result? I.e. that UHI is responsible for at most 0.05 deg/century of apparent warming? Graft 19:51, 31 Jan 2005 (UTC)

Are you implying the UHIE does not influence urban stations? Because that is what the article says. No one said that UHIE adds to Global Warming. --D. Norris 20:20, Jan 31, 2005 (UTC)

The contention you are making is that UHIE distorts the temperature record in urban stations, thus suggesting an apparent warming where there is actually no significant warming. This has been studied and reported in the TAR; the contribution of the UHIE to apparent (observed) warming is only 0.05/century. The rest of the observed warming is due to something else (e.g. a real warming trend). Is that clear enough? Does anyone dispute that claim? If not, why the emphasis on the UHIE? Graft 20:48, 31 Jan 2005 (UTC)

Are you saying UHIE doesn't influence urban monitoring stations? Do you have a source on that? --D. Norris 20:55, Jan 31, 2005 (UTC)

Ugh, no. I'm saying the amount by which the UHIE distorts the temperature record is statistically insignificant. That is, the trend is the same whether you consider all data or only non-urban stations. Check out: Easterling et al, Science, 277 364-367. Graft 21:03, 31 Jan 2005 (UTC)

Oh Good, then we agree! I will restore the UHIE affects individual stations and leave in that it is thought not to be significant. --D. Norris 21:20, Jan 31, 2005 (UTC)

(William M. Connolley 21:25, 31 Jan 2005 (UTC)) Don't be silly.

(William M. Connolley 21:25, 31 Jan 2005 (UTC)) Of course it was sourced, to the urban heat island page. Its all there you know... a couple of comments: this is one area where the IPCC TAR is slightly out of date: more recent work (its all on the UHI page) from Petersen (for the US) and Parker (globally) suggests a *lower* influence from the UHI than the TARs estimate. And the 0.05 is an upper bound, not a best guess. Perhaps I should read Easterling, too.

Err, right, upper bound - I misspoke. Easterling says nothing as far as that number, but does do comparison of urban vs. non-urban based on a meta dataset defining "urban" stations, and concludes there's nothing of significance.

D. Norris, do you have some purpose here other than FUD? I'm still unclear why you feel all of this needs to be played up so much. Can you clarify the nature of the disagreement in the following sentence? While the accuracy of the collected station data is not in dispute, the records suffer from incomplete coverage, geographically and historically, making the conclusions drawn from the data subject to disagreement. Graft 21:51, 31 Jan 2005 (UTC)

Why I am here is immaterial. If you wish to start resorting to ad hominem attacks and snide comments, I doubt we will have a constructive dialog.

Since pretty much I wrote the sentence to which you refer, I doubt I am in dispute with it. Dr C. seems to be the one who keeps editing it out, so you best ask him the same question! Right now, I am quite satisfied with the text on UHIE as it stands with your recent edits. --D. Norris 22:09, Jan 31, 2005 (UTC)

Sorry - I don't mean "do you have some purpose here" as in "on Wikipedia", i mean, "in pressing this debate". And the disagreement to which I refer is the one mentioned in that sentence: "...conclusions drawn from the data subject to disagreement." What is the nature of the disagreement in question? Simply throwing up a fog around the subject will not do - we should be clear. Graft 22:13, 31 Jan 2005 (UTC)

Apology Accepted. Moving on - If you don't feel that there is any disagreement that the GIS is compromised because of issues with reporting duration and geographical coverage, then perhaps you can explain why NASA specifically states that they exclude stations? I sourced it right there! --D. Norris 22:30, Jan 31, 2005 (UTC)

I'd just like to point out that if there's a problem with the pre-1990 temperatures in 1990, that problem will not be resolved in the pre-1990 temperatures by 2005. We can't go back in time and retake old temperatures, we can simply rehash the old data. — Cortonin | Talk 01:09, 1 Feb 2005 (UTC)

(William M. Connolley 09:24, 1 Feb 2005 (UTC)) Not necessarily true, in fact quite likely wrong. There has been an awful lot of work on the T record over the last 15 years - its quite an "hot" topic you know. People have improved the corrections to old data and found old stuff not previously available. Also, L's piece is not a research article on this - more a comment piece. Ie, its not a primary source.

WV is not the dominant GHG

(William M. Connolley 09:42, 1 Feb 2005 (UTC)) This keeps coming up. WV is not the dominant GHG. It is the largest contributor to the effect (60-70%) but it is "submissive" rather than dominant. This comes up so often I wrote about it: http://mustelid.blogspot.com/2005/01/water-vapour-is-not-dominant.html

I believe that's more of a semantical argument. We're not talking about sexual dominance, nor are we talking about control. What is really trying to be said is that water vapor is the most significant greenhouse gas in the sense of contributing the largest portion to the greenhouse effect, but the trick is to say that while avoiding the POV of "significance" in terms of "importance". I think there should be no statements at all about which greenhouse gas is most "important", since any assessment of importance would be entirely POV. The word "largest" invokes images of size more than effect size, which just makes it not seem like the best word choice. There are only a few short English phrases I can think of that might describe it: "the most significant", "the dominant", "the major", "the primary", "the principal", and "the most prominent". And the challenge is to pick the best of these. — Cortonin | Talk 19:24, 1 Feb 2005 (UTC)

In the process of doing this, we must avoid phrases like, "the greenhouse effect, caused principally by anthropogenic emissions of carbon dioxide." I think we can all agree that's incorrect, since everyone pretty much agrees that carbon dioxide is not the greenhouse gas with the largest contribution. — Cortonin | Talk 19:24, 1 Feb 2005 (UTC)

(William M. Connolley 20:49, 1 Feb 2005 (UTC)) If you quote the sentence in full, you objections are resolved: it says: The most common global warming theories attribute temperature increases to increases in the greenhouse effect caused principally by human-generated (anthropogenic) emissions of carbon dioxide.. Which is correct. However, to avoid ambiguity, I've reworded it slightly.

It's sort of like saying, "It can't be concluded, either within or outside of England, that by any reasonable conclusion William M. Connolley kicks puppies." Technically this sentence says that you don't kick puppies, yet it certainly doesn't feel like it's saying that when you read the sentence. — Cortonin | Talk 02:49, 2 Feb 2005 (UTC)

It doesn't fix it to say, "increases in the greenhouse effect, those increases caused principally by human-generated (anthropogenic) emissions of carbon dioxide", because the climate models which are predicting significant increases to the greenhouse effect do not receive this principally from carbon dioxide, but instead from positive feedback, and this is too complicated to explain correctly in the opening paragraph. Let's leave the first paragraph simple, outline the topic in the next couple paragraphs, and then provide detail further down. — Cortonin | Talk 02:49, 2 Feb 2005 (UTC)

This may help in writing:

B.7 I understand water vapour dominates the natural greenhouse effect. Doesn't this make changes in the concentrations of other greenhouse gases insignificant? Response: No! While water vapour represents about two-thirds of the natural greenhouse gases, changes in its concentrations are determined primarily by changes in atmospheric temperature and related effects on the hydrological cycle. As increases in other greenhouse gases warm the atmosphere and surface, the amount of water vapour also increases, amplifying the initial warming effect of the other greenhouse gases. Background: Water vapour is indeed one of the most potent and abundant greenhouse gases in the atmosphere. If the effects of all greenhouse gases other than water vapour were ignored, the natural greenhouse effect would be about 60-70% of observed values, compared to about 25% if only CO2 were present. However, humans have little direct effect on water vapour concentrations. Rather, its concentrations respond to changes in temperature and other natural atmospheric processes. Warmer atmospheric temperatures, whether caused by increased greenhouse gas concentrations or other causes, increase the amount of water vapour that the atmosphere can hold. Likewise, warmer surface temperatures increase the rate of global evaporation of water from land ecosystems and ocean surfaces. Much of the increased evaporation comes down again as increased precipitation, but some remains in the atmosphere as water vapour. During recent decades, for example, a rise in global temperatures has been accompanied by an increase in global precipitation and observations of rising moisture content of the atmosphere over many parts of the world. The increase in water vapour also affects other aspects of the climate system, particularly clouds. Most scientists agree that the overall effect of the direct and indirect feedbacks caused by increased water vapour content of the atmosphere significantly enhances the initial warming that caused the increase - that is, it is a strong positive feedback. However, the magnitude of this effect depends on where the increases take place within the atmosphere. If these occur in atmospheric regions where air is already near saturation levels, the additional effect is small. If, on the other hand, it occurs in dry air like that over deserts or in the upper troposphere, the effect can be very large. Most models suggest that the enhancement effect will be quite large (on the order of 60%). However, this feedback is very complex, and its magnitude remains one of the key uncertainties in climate models. Reference: IPPC, 1990 WGI, pp 47-48.

Source Metereological Service of Canada

Urban Heat Islands

This statement, "Recent research shows that the US (and global) records are not much influenced by the Urban heat island" seems to be in both versions of this page, but it is quite conspicuously undocumented. The statement appears to be referring to some specific recent research, but I see no external reference to any of that specific research. We have to be careful with statements like that, because the phrase "recent research" is a powerful one to the reader, and so when it is used it should be documented. I would also suggest the word "indicates" rather than "shows", since all recent research is only indicative until it has had a chance to be tested and evaluated by time. — Cortonin | Talk 19:28, 1 Feb 2005 (UTC)

(William M. Connolley 20:45, 1 Feb 2005 (UTC)) Its fully referenced in the UHI article. Furthermore, both verions contain " (Peterson 2003; Parker 2004)" which are the references. Just how much more do you need?

First, that's a fairly incomplete referencing style. It's okay to use that in a journal article if the end of the article then contains a more detailed reference. But it's completely ineffective in that form. There are 3.8 million google hits for Peterson 2003. The first environmental researcher listed is this woman [11], but I see no publications from 2003 on this topic (although she does have many publications from 2003, indicating the magnitude of the problem in using a poor reference format like that). One of the hits is this ppt slide [12] which does actually describe research on the topic of urban heat islands, but is quite unimpressive in its description of the methodology. He takes temperature measurements, categorizes them by type of location, then subtracts off differences in temperature by type of location, and then concludes, "Oh look, now the urban heat island effect is smaller. Those silly people who were saying it was significant were simply biased." The mechanism of categorizing temperatures by location and then subtracting off the effects found in locations of a certain type is a fairly sketchy and dubious way of "showing" that there is no contribution from locations of another certain type. If I were sitting at the conference where that talk was given you can bet my hand would be in the air asking about confounding correlations, and yours should be too. — Cortonin | Talk 18:30, 3 Feb 2005 (UTC)

(William M. Connolley 09:52, 7 Feb 2005 (UTC)) Have you really not taken the trouble to follow the link to the UHI page? Please do that, find the correct references which are, appropriately, listed there; and read them.

Unspecified disagreement

D. Norris, I'm still unclear on this:

the disagreement to which I refer is the one mentioned in that sentence: "...conclusions drawn from the data subject to disagreement." What is the nature of the disagreement in question? Simply throwing up a fog around the subject will not do - we should be clear. Graft 22:13, 31 Jan 2005 (UTC)

Apology Accepted. Moving on - If you don't feel that there is any disagreement that the GIS is compromised because of issues with reporting duration and geographical coverage, then perhaps you can explain why NASA specifically states that they exclude stations? I sourced it right there! --D. Norris 22:30, Jan 31, 2005 (UTC)

NASA excludes stations to remove distortions from the UHI - this has absolutely nothing to do with the incompleteness of temperature records, so I don't know why you bring this up. Furthermore, I am asking HOW temperature trend estimates are compromised by incompleteness of the record - do you have a source that states this is a substantial problem not allowing reconstruction and accurate estimates? NASA seems to think they can do it okay from 1800 on, if this is the source you're relying on. Obviously spotty data is worse than complete data, but your text implies "Spotty data means we can't really know what's going on." Who makes this claim? Graft 22:44, 1 Feb 2005 (UTC)

NASA excludes an unspecified number of the stations for those graphs. Look at the station graphs:

http://www.giss.nasa.gov/data/update/gistemp/stations.gif and read the text:

http://www.giss.nasa.gov/data/update/gistemp/

Specifically:

In our analysis, we can only use stations with reasonably long, consistently measured time records.

What remains unclear is defination of reasonably long. Also judging from the graphs, about 50% of the stations have record length of less than 40 years, which would be about 1965. This makes the preceding 85 years represented by less then 50% of the sample.

Let assume reasonably long is 50 yrs.

a) Less then 3000 stations would be included.

b) Less then 80% of the NH and less than 50% of the SE is located with in 1200 km of a station.

Assume reasonably long is 100 yrs.

a) About 1000 stations included

b) Less than 65% of the NE and less than 30% of the SE is located with in 1200 km of a station.

BTW, within 1200 km would out to be about 4.9 million sq km of coverage for a station.

Sounds a little spotty to me. --D. Norris 23:52, Feb 1, 2005 (UTC)

Sorry for the late response... Anyway, you should read Hansen's paper, it answers a good number of these issues, on how the data was cleaned and constructed, as well as the distribution of station coverage for select years. And the relevant question remains: "Sounds a little spotty to me" is not justification for the sentence above. Your opinion is irrelevant; is there a published (or even non-published) paper by a scientist in the field which states clearly why Hansen's paper is incorrect, or what the source of error is? Otherwise, we should not report that it is "subject to dispute". Graft 17:54, 6 Feb 2005 (UTC)

What is the source of the graph of US data?

I looked at the link in the text which pointed to figure 2.9, however those are not graphs.--Silverback 14:29, 2 Feb 2005 (UTC)

NASA. Check the 'graphs' link that page. --D. Norris 18:48, Feb 2, 2005 (UTC)

I have removed this text and its accompanying graph:

The temperature increase has not been uniform over the globe or over time. For example, the chart showing US temperatures from 1880 to 2005 and shows a much smaller overall warming trend than similar global data. This implies that other areas show warming trends larger than the global trend [13].

This discussion of the chart does not appear to be correct. The chart does not show a smaller overall warming trend than the similar global data, in fact, it does not show any global data at all. To my eyes there does appear to be a warming trend, but the chart does not aid one is assessing that trend relative to any global trend. What is the purpose of the chart and this text? Does this data pose a problem for conclusions about the overall global warming trend? Is there a citation for that? How about the word "much", is there a cite for that word, it doesn't seem scientific. Perhaps the original was statistically significant smaller trend, which is quite different than "much smaller". "much smaller" would be saying something about the difference in the absolute size the of trend rather than the strength of the statistics, after all, a slightly smaller trend, can also be statistically significantly smaller, if the statistics are good enough.--Silverback 21:08, 3 Feb 2005 (UTC)

I think perhaps you're just misreading it, which is probably an indicator that it should be worded more clearly. I took the text to mean that the chart shows a U.S.-wide smaller warming trend than other charts have shown for the global trend. And yes, some consider this significant given the different standards of data acquisition between the datasets. See page 3 of [14]. — Cortonin | Talk 05:44, 4 Feb 2005 (UTC)

Thanx for the reference. Reading the article, I can see the points that the author makes with the US data. He argues that it is the best data, yet it shows a smaller trend than what is being published as the global trend. He argues that the US data, since it is over a smaller area, should show more variability than the globally averaged data, instead it shows less variability, from which he argues that the global data was not yet of the statistical quality to show the lower variability that it should. While his arguement about variability and smaller area is correct in the statistical sense, such an argument is based upon the statistical assumption of random sampling, which is hardly true here. Arguments can be made that the continental US, lying in the band of westerlies just east of the northern hemisphere's largest body of water, and with weather systems that are also strongly influenced by moisture from the gulfs of California and Mexico and the even the great lakes, could possibly be less a naturally less variable climate area, at least compared to the large land mass of asia and the more northerly and gulf stream dependent Europe. I think the case he makes is a strong one, especially when the global and historical data are included, but his case is for uncertainty and variability larger than any conclusions that can be drawn from the data.

Given the complexity of the case that he is making, using the US data they way that has been proposed in the edit wars in this article is an oversimplification, and correctly using it would be difficult and not germaine to the issues that are most important at this time. At the time of the 1990 analysis you referenced, the skepticism and uncertainty this author argues for had broad support. What changed that were publications such as those by Mann, and it is the repercussions of the criticisms and refutation of the Mann analysis as they play out this month and later this year in the IPCC meetings that will do more to restore the 1990 skepticism than a rehashing of the arguments made at that time. With the hockey stick in dispute, the magnitude of the natural variability is restored to that suggested by the paleo data, and any modern warming falls easily within that variability. I don't think the level of detail required to make the US data useful and in proper perspective belongs in this "Global warming" article.--Silverback 15:39, 4 Feb 2005 (UTC)

I don't think the complete statistical analysis is necessary for this article either. But I think a quick summary of the possible implications of the U.S. data is perfectly appropriate, and a reference can simply be added for those who care to see the more detailed description of why that is. I do hope you're correct that some more skepticism and questioning of conclusions will return to the community following the criticism of the Mann analysis, but it remains to be seen if that will occur. Once conclusions are accepted, it's often very difficult for people to move back toward questioning them, even if critical support for those conclusions is removed. — Cortonin | Talk 00:07, 7 Feb 2005 (UTC)

Comparing the two versions

Let's compare the two versions in dispute:

1. The WMC version states definitively that increases in the greenhouse effect are principally by anthropogenic emissions of carbon dioxide, a complex statement which to document requires extensive supporting arguments involving climate models with significant uncertainty or appeals to consensus, and even with that is stating conclusively the perspective of only one point of view (which by the style guide should be avoided whenever more neutral language is an equal option).

2. The version put forth by Denorris, Cortonin, et al. contains an ever so slightly simpler and more NPOV opening paragraph which postpones pushing any particular perspective, contains an explanatory introductory paragraph which correctly summarizes the relationship between CO2, water vapor, and the greenhouse effect while explaining that global warming theories examine the mechanisms of the interaction of these things, contains additional temperature information in graph form, and contains data from NASA documenting the contributions of the urban heat island effect.

Now, let's review. Which version could possibly be more NPOV? Version 1, which removes all the information and states a single perspective definitively in the opening paragraph, or version 2, which does not push a perspective but simply provides more detailed explanation and documented information? — Cortonin | Talk 18:03, 3 Feb 2005 (UTC)

(William M. Connolley 18:30, 3 Feb 2005 (UTC)) The above just shows how POV your version is. The UHI effect is fully described on the UHI page. Details like that should be there. The lower-48-US graph is a small region and doesn't deserve prominence - the only reason you want it there is because it shows lower-than-average warming. Had it shown higher-than-avg you would have removed it immeadiately with loud cries of "POV!". The opening statement: that increases in the GHE are caused by emissions of anthro GHG, principally CO2, is the std consensus, so by wiki policy belongs at the start, not your weakened version. Even mentioning WV in this context is POV, because it implies it has some important determining property, which it doesn't. You only want it there to muddy the water.

No need to shout! You (Cortonin) wrote: "NOT NPOV TO DEFINITIVELY SAY HUMAN CONTRIBUTION CAUSED INCREASE.", but the original sentence never did so. It was all qualified by "the most common global warming theories"....

I'll try to create a reasonable version that keeps the links and reads nicer. --Stephan Schulz 12:03, 4 Feb 2005 (UTC)

The qualifier did not in any clear way cover the last clause. See above for where I described this. It is also not sufficiently clear to say that common theories predict carbon dioxide to be the primary cause of temperature rises. At best, common theories attribute carbon dioxide to be the initial instigator, and then invoke an entire host of positive feedback mechanisms to amplify this to a sufficiently scary number. I don't think "primarily cause" is at all the right way to phrase that, because it's complicated. That's why I have been advocating for it to be explained more clearly later. First, there are significant positive feedback mechanisms with water vapor. There are also positive feedback mechanisms proposed with plankton or with polar ice melting (such that the ice will no longer reflect as much incident radiation) that are expected by some to cause accelerating feedback [15]. There are also positive feedback mechanisms predicted involving weather patterns [16]. With all these complex doomsday mechanisms being thrown forth, I don't think it's at all sufficient to just begin the article by saying it's all due to anthropogenic carbon dioxide. If it IS all just anthropogenic carbon dioxide, then we don't have a whole lot to worry about as far as increases in temperature. — Cortonin | Talk 19:41, 4 Feb 2005 (UTC)

Clarification of these feedback mechanisms is important, and they are quite notably missing from the article. Every mention I've tried to make of feedbacks has gotten reverted. The only mentions of the word "feedback" in the article (all three of them) are bundled with the word "skeptics" or "critics". Why? The proponents of global warming themselves are the ones who put forth all the positive feedback mechanisms in order to get the predictions they calculate, so why are all mention of these being reverted by the proponents of global warming who are editing the article? This does not make sense. Why is there a push to imply that it's all just directly anthropogenic CO2, when that's not what the theories are proposing, and when that alone is not calculated to produce significant warming? — Cortonin | Talk 19:41, 4 Feb 2005 (UTC)

(William M. Connolley 20:30, 4 Feb 2005 (UTC)) "my" version, says, correctly, that the common theories attribute the warming to CO2. There are indeed a host of feedback mechanisms but the root cause is CO2 and this is what the intro should say. If a boulder was poised at the top of the mountain and someone came and gave it a little push that set it bouncing off down to smash into a village, would you quibble that the root cause was the push, or would you insist on a pile of qualifiers about the main force being gravity; and that a detailed investigation of the topography was necessary to trace the path of the boulder?

A couple of questions for WMC: First, are you a climatologist or mathemetician - in what discipline was your doctorate granted?

Stick to the issues, this ad hominem stuff is irrelevant.--Silverback 16:36, 5 Feb 2005 (UTC)

What ad hominem? It is a simple question.--JonGwynne 11:13, 6 Feb 2005 (UTC)

Second, with regard to your "boulder" analogy, is the boulder meant to represent CO₂? If so, don't you think that's a rather inaccurate analogy since carbon dioxide only makes up a tiny fraction of the atmosphere and its "greenhouse factor" is a fraction of other gasses? In fact, what direct evidence is there that CO₂ is a primary contributor to the apparent increase in global temperatures?

(William M. Connolley 17:38, 5 Feb 2005 (UTC)) Read the IPCC report if you're interested. Or the wiki pages, indeed.

Those documents that I have read don't answer the question, that's why I'm asking. If you don't know the answer just say so. and I'll ask someone else.--JonGwynne 11:13, 6 Feb 2005 (UTC)

How, for example, do you reconcile the claim that CO₂ is a major factor with the fact that, for several decades during the 20^th century, global temperatures decreased significantly in spite of a rapid increase in the CO₂ content of the atmosphere? It seems to me that there are some fundamental questions of causality to resolve before anyone can claim to be certain about CO₂'s role in global temperature. Wouldn't you agree?--JonGwynne 14:29, 5 Feb 2005 (UTC)

sulfate aerosols of vulcanic origin, solar variation? Both are orthogonal to greenhouse gas warming. You aren't claiming these climate variations are due to water vapor effects. CO2 has more impact on global climate, because its half life is longer allowing time to mix completely in both hemispheres, so is long enough that it is accumulating raising average greenhouse effects. The half life water vapor is short, it is not accumulating, although there is some positive feedback with temperature increases, resulting in more H20 in the atmosphere, countered in some poorly modeled way by the formation of aerosols such as clouds.--Silverback 16:34, 5 Feb 2005 (UTC)

Solar variation isn't relevant to global temperature? That's seems an odd claim to make. The fact that solar activity has increased seems particularly relevant to the discussion of global temperatures, don't you think?--JonGwynne 11:13, 6 Feb 2005 (UTC)

The sentence says: both are orthogonal to greenhouse gas warming (not "global temperature"). I think that's pretty clear, and true. Also, you'll note we have an extensive discussion of solar variation in the text, so I don't know what you're complaining about. Graft 18:25, 6 Feb 2005 (UTC)

(William M. Connolley 17:38, 5 Feb 2005 (UTC)) JG has been fooled by Michael Crichton, sadly. Anthro sulphate aerosols, plus a little natural variability, is the answer: its all in the IPCC report. It seems to me that there are fundamental questions of not-bothering-to-read-the-science that some people need to answer.

Ah, so when the change is in the direction you're not trying to predict, then we can attribute it to natural variation, but when the change is in the direction you ARE trying to predict, then we have to say it's primarily anthropogenic. Thanks for clearing that up. — Cortonin | Talk 01:13, 6 Feb 2005 (UTC)

WMC's problem is that he's an IPCC "true believer". Everything the IPCC says, in his view, is correct and everything that even questions (much less contradicts) it is automatically wrong.--JonGwynne 11:13, 6 Feb 2005 (UTC)

Well, the relevant question is, what DO you attribute it to? Anyway, (non-volcanic) sulphate aerosols are obviously anthropogenic, so your statement is a bit of a puzzle. Graft 18:25, 6 Feb 2005 (UTC)

Error bars on the global graph

(William M. Connolley 17:15, 5 Feb 2005 (UTC)) Henrygb is correct - good catch - there *are* no error bars on the graph, as is plain for anyone to see. So the Uncertainty bars (95% confidence limits) shown for both the annual and 5-year means, account only for incomplete spatial sampling of data (added by Ms Norris: [17]) is wrong and should be left out.

The correct graph with error bars is available here: [18]. Denorris simply grabbed the pdf without the error bars when she was making the image. — Cortonin | Talk 01:19, 6 Feb 2005 (UTC)

water vapor

I'm still unhappy with this "water vapor" bit. The lay reader will conclude that water vapor is responsible for warming the planet, whereas this is not really very accurate, since, well, it precipitates. In the absence of other greenhouse gases, the water content of the atmosphere would be nothing. The page should make this clear, and it doesn't. I appreciate the desire to instruct the reader on the mechanistics of the greenhouse effect, but really I think it's just confusing the way it's presented right now. Graft 18:38, 6 Feb 2005 (UTC)

There doesn't seem to be any question that WV has a much greater effect with regard to warming the planet (i.e. contributing to the greenhouse effect) than CO2. Also, I'm not sure what you mean when you say "In the absence of other greenhouse gases, the water content of the atmosphere would be nothing". Are you suggesting that if there were no CO2 in the atmosphere, then water wouldn't evaporate?--JonGwynne 19:48, 6 Feb 2005 (UTC)

Roughly, yes. Feedback would take care of that, I would think. Anyway, the point is that the presentation is silly. What's important is not how much physical radiance is being absorbed by which gas, but what will happen as a result of incremental changes in gas concentration. Correct? That is, water vapor may be responsible for the "majority of the greenhouse effect", but you do not wish to state that water vapor is responsible for changes in the magnitude of the effect, do you? That's the meaning being communicated by the current form of the text. Graft 21:10, 6 Feb 2005 (UTC)

But isn't the question of what is causing the apparent warming of the atmosphere the central issue? If primary contributor to increased global temperature is water vapor, then what's the point about fretting over CO2 levels? BTW, just so we're clear, I think burning fossil fuels is a bad idea. I am very much in favor of switching to renewables like biodiesel (as opposed to impractical daydreams like hydrogen fuel cells or nuclear power). That being said, I think that the questionable science and questionable conclusions of environmental radicals are actually damaging the cause of environmentalism. Good public policy cannot come from bad science. Water vapor precipitates out of the atmosphere as rain? Sure it does. But then water absorbs CO2 as well. So does new plant growth. To quote the 2001 IPCC report's Summary for Policymakers [19]: "On land, the uptake of anthropogenic CO2 very likely exceeded the release of CO2 by deforestation during the 1990s". Indicentally, the summary also shows graphs comparing temperature trends based on their "best guesses" (see page 11) which even when anthropogenic effects are excluded, still shows a warming trend. p.s. Thanks for having the class to engage in discussing these issues. There are far too many people here who lack the rudiments of civility. Cheers! --JonGwynne 21:53, 6 Feb 2005 (UTC)

(William M. Connolley 22:06, 6 Feb 2005 (UTC)) Not quite: the question is, what is causing the observed temperatue increases. And the answer is, anthropgenic emissions of GHGs, as all attribution studies show. As for WV, see http://mustelid.blogspot.com/2005/01/water-vapour-is-not-dominant.html: the point, again, is that WV *reacts* to increases in forcing from other quantities. I'm not sure what your IPCC quote is supposed to mean: fossil fuel emissions are much larger anyway.

No, actually, the answer is "you don't know what is causing the observed temperature increases". You guess it is anthopogenic greenhouse gasses but you have yet to demonstrate that solar radiation is able to distinguish between anthropogenic and non-anthropogenic greenhouse gasses. And what's the point about dwelling on the short amount of time that a specific quantity of water vapor may remain in the atmosphere? You're not seriously trying to argue that there isn't more water vaporizing every second to take the place of that which condenses out of the air as rain, are you?--JonGwynne 23:11, 6 Feb 2005 (UTC)

(William M. Connolley 09:41, 7 Feb 2005 (UTC)) We don't guess, there is an awful lot of scientific research that has gone into attribution, all of which you are ignorant of, sadly. Look at the attribution page, or in the IPCC report, and stop this nonsense about "guessing". As for WV... I'm sorry that you still don't understand... WV is in dynamic balance, of course.

Just out of curiosity, who is "we"? But getting back to the matter at hand, Of course you guess. Climate models are inheretly guesswork. You claim there is evidence that a direct cause-effect relationship has been established between CO2 levels and climate change and yet you declime to provide a link to that evidence. Hmmmm, this smacks of the 3rd-grade "I know the answer but I'm not going to tell you what it is" school of argument. You say I don't understand about water vapor, then spell it out. If I make a statement that someone doesn't understand, I'm willing to take the time to explain it to them. Why aren't you?--JonGwynne 12:32, 7 Feb 2005 (UTC)

(William M. Connolley 14:30, 7 Feb 2005 (UTC)) We is scientists, of course. The links are on the attribution paeg, where they belong. As for WV, I've posted this above, but you're not so good at fnding things, so I'll post it again: http://mustelid.blogspot.com/2005/01/water-vapour-is-not-dominant.html

Holy bloated ego Batman! William, are you seriously offering your own blogs as independent scientific evidence, while claiming to speak for all scientists?! I'll give you the benefit of the doubt that not even you are that arrogant and misguided. Still, there doesn't seem to be any other reasonable interpretation of your statements. Maybe you want to provide one.

(William M. Connolley 17:22, 7 Feb 2005 (UTC)) The obvious one: you said that you didn't understand the situation, and wanted an explanation. I've provided one for you. You said: You say I don't understand about water vapor, then spell it out. I've just done so. Now, instead of flinging insults around, why don't you actually study the page and, if you disagree with it, point out some substantive errors?

How about the substantive error that you said CO2 is not reactive. First, every pre-industrial temperature plot I've seen shows temperature fluctuations LEADING CO2 fluctuations, which indicates that CO2 levels may actually respond to temperature more significantly than they drive it. In addition, half of all anthropogenic CO2 has already been absorbed by oceanic or biomass CO2 sinks. — Cortonin | Talk 20:40, 7 Feb 2005 (UTC)

Sorry, William, I should have specified that I wanted something more substantive than one of your blogs. I have read the page and there isn't really anything there that warrants a response. It is simply your opinion with no independant corroboration. You're certainly entitled to your opinion but to try to pass it off as absolute truth, must less claiming to speak for all scientists is something entirely different.--JonGwynne 23:03, 7 Feb 2005 (UTC)

In the meantime, perhaps I should have been more specific. Why aren't you willing to provide independently-reproducible, peer-reviewed evidence that anthropogenic greenhouse gasses are the primary cause of global warming?

(William M. Connolley 17:22, 7 Feb 2005 (UTC)) As I've said repeatedly, go look on the attribution page - its all there.

Meanwhile, a quick trip to wikipedia's global warming page reveals that the atmosphere is responsible for absorbing 16% of incoming solar radiation and CO2 is responsible for absorbing 26% of that - or a little more than 4% of the total. --JonGwynne 15:37, 7 Feb 2005 (UTC)

The point WMC has been making is that if you add more water vapor to the atmosphere, it just gets rained out within a few days - it doesn't result in runaway warming. On the other hand, CO2 (and CH4) cannot be rained out of the atmosphere as quickly. It stays there, and causes incremental warming, and positive feedback, resulting in more water vapor in the atmosphere and more CO2 being released by the oceans. Etc., etc. In other words, the behavior of CO2 and H2O in the atmosphere is very different - even though it only accounts for a fraction of the GHE, it can play a far bigger role in shaping the behavior of the atmosphere (like a catalyst).

Also, I'm unclear on your above comment: you have yet to demonstrate that solar radiation is able to distinguish between anthropogenic and non-anthropogenic greenhouse gasses. This is not what anyone is claiming; the claim of climate modelers is that the increase in temperature is a result of increase in greenhouse gas concentrations as a result of human contribution. Obviously sunlight can't tell the difference between "natural" CO2 and anthropogenic CO2. But, if that additional CO2 were not present, climate models show that we would not have had the additional warming we observe.

Finally, can we have less insults being thrown around? They really don't do much to help the atmosphere. Graft 17:00, 7 Feb 2005 (UTC)

First point, CO2 is also absorbed quickly - though both water and plantlife. I don't dispute that CO2 increases the greenhouse effect, but I have yet to see any indication that is is causing more warming that is proportional to the increase. The increase in CO2 since the beginning of the industrial revolution represents 0.01% of the entire atmosphere. The portion of solar radiation absorbed as heat by the entire CO2 content of the atmosphere amounts to 4%. Second, climate models don't "show" anything. They are theoretical - at best an "educated guess". But anyone who knows about computers will tell you that we are still a long way from being able to build one powerful enough to accurately model a system as complex as the earth's climate. To claim that what climate models predict is factual is to blunder into fantasy. Just look at the amount of "tuning" that these models require so that their output will match known trends. Get William to explain about tuning these models. It is techno-jargon for "fudging the data".--JonGwynne 23:03, 7 Feb 2005 (UTC)

WMC, could you please document "all attribution studies"? Thanks. — Cortonin | Talk 00:38, 7 Feb 2005 (UTC)

(William M. Connolley 09:41, 7 Feb 2005 (UTC)) Try the attribution page.

Well, unsurprisingly, the attribution page strongly corresponds to your POV. So I decided to see precisely how difficult it was to find peer reviewed papers which point to other attributions. I went to ISI Web of Science, the standard starting point for such a literature search, and typed in "global warming". Sure enough, literally the VERY first result returned attributed the bulk of observed warming to sunspot and solar cycle variations. And by following the references within that paper, within a matter of minutes I was able to find a number of other papers which attribute observed warming to solar fluctuations. — Cortonin | Talk 20:02, 7 Feb 2005 (UTC)

(William M. Connolley 20:41, 7 Feb 2005 (UTC)) The links you put in to Njau are a bit desparate... see my comments on the talk page there. Did you check the citation results for his papers?

"After discarding all data to the contrary, the hypothesis was proven." -- Anonymous. — Cortonin | Talk 21:23, 7 Feb 2005 (UTC)

Well, Njau is cited by only himself, which sort of diminishes his credibility. And there are plenty of other papers dealing with the subject of solar variation which pretty handily put it to rest as the source of warming. Graft 21:34, 7 Feb 2005 (UTC)

(William M. Connolley 21:45, 7 Feb 2005 (UTC)) Cortonin, this is a rather poor response. You have asserted that you are a scientist, I think: you know that an uncited paper in a minor journal lacks credibility.

That's funny, because in my schooling they taught me that science was assessed by its merits, and not by argument from authority. The paper makes a clear testable prediction, that the temperature will begin to drop, and if it does not, then the paper is incorrect. — Cortonin | Talk 22:34, 7 Feb 2005 (UTC)

It is doubly funny coming from someone who cites his own blogs as independent confirmation.--JonGwynne 23:03, 7 Feb 2005 (UTC)

Can you please stop sniping? It's very off-putting. From reading the conversation it's clear he gave that link in response to your plea for clarification on the point about water vapor. You didn't demand a journal article on the subject, and he didn't claim he was giving you one. Stop harassing people. Graft 23:09, 7 Feb 2005 (UTC)

I sincerely apologize to you for my behavior. I know I should be above this sort of thing, but sadly, I'm just not. I know "he started it" is a lame excuse but it is all I've got. I'm sure that others could ignore WMC's provocations, but I'm simply not strong enough. I come from a long line of "puncturers of pomposity" and WMC is too egregious an example for me not to call him on it. You're right, WMC didn't claim that his blog was a journal article, but in fairness to me, I did ask for "evidence". In the scientific circles which WMC claims to inhabit, this usually means something definitive like a journal article documenting an experiment whose results are reproducible and have been independently verified - something that has been subject to scrutiny and, yes William, skepticism. The things that still astonishes me about him is that he claims to regard skepticism as a bad thing. I realize that this may not be everyone's view, but I believe that credulousness is not a positive trait for a scientist. Finally, let me thank you again for keeping things on a civil level and for trying to encourage it in others.--JonGwynne 00:06, 8 Feb 2005 (UTC)

UHI

Cortonin, can you provide a reference demonstrating that UHIs significantly distort the temperature record? I have three separate sources (Easterling 1997, Hansen 1999 and Peterson 2003) that say there's nothing to be seen there. Graft 20:53, 7 Feb 2005 (UTC)

Well we know that the UHI effect exists and is much larger than the reported global warming, as the UHI effect is known to make urban air about 6 C hotter than rural air [20], and we know that plenty of temperature sites are located in heat islands [21]. The real question then, is does the heat island effect contribute to a measured RISE in temperature? If you look at Streutker 2003 (Remote Sensing of Environment 85:3), for example, you'll see a satellite analysis of Houston which shows the heat island there is rising by about 0.6 C per decade. Now obviously that localized effect far exceeds the reported global temperature rise. If you want to see a wide assortment of papers discussing the significance of urban heat islands, then you probably wouldn't have to look much farther than the dozen or so papers Peterson tries to dispute in his 2003 J. Climate article on that topic. — Cortonin | Talk 22:22, 7 Feb 2005 (UTC)

I'm not disputing the effect exists; that's not the issue. I'm saying, is there anyone who claims that it rubbishes attempts to estimate the global temperature record? In other words, does temperature estimated from all stations differ from temperature estimated from only rural stations? Graft 22:38, 7 Feb 2005 (UTC)

Global temperature change

The change is expressed in degrees celcius difference between what the temperature now is compared to what it should have been. But the actual temperature isn't listed. Can someone add this?--JonGwynne 01:19, 8 Feb 2005 (UTC)

INQUA

WMC, could you explain your removal? I don't know anything about this commission, but it seems to exist... claims to have a list of members... etc. What gives? Graft 21:25, 8 Feb 2005 (UTC)

(William M. Connolley 21:45, 8 Feb 2005 (UTC)) Morner has long been a loose cannon, using "his" commission as authority to push his weird views. INQUA finally got sick of him, got rid of the commission, and told him to stop misrepresenting himself [22] - see also Talk:Sea level rise.

(William M. Connolley 22:18, 8 Feb 2005 (UTC)) I've re-removed this after Cortonin re-added it in modified form:

Nils-Axel Mörner, the former president of the INQUA Commission on Sea Level Changes and Coastal Evolution disagrees with the IPCC evaluation: "All handling by IPCC of the Sea Level questions have been done in a way that cannot be accepted and that certainly not concur with modern knowledge of the mode and mechanism of sea level changes." [23]

The problem here is that Morner is still orrowing his authority from INQUA, which has rejected him. The website: http://www.pog.su.se/sea/14_news.htm truncates to http://www.pog.su.se/sea which is invalid: this commission doesn't exist anymore. Morner has been told to take this site down and stop misrepresenting himself. This site now has a status lower than some-bods-webpages, because its some bod misrepresenting themselves. If you can find Morners views in a reputable source - ideally a real publication - then fine; but not from this website.

That site is from 2000, when the commission DID exist, and WAS part of INQUA, and DID "borrow authority" from INQUA for whatever that's worth. Look at the News page, there hasn't been an update since 2000, and the commission existed until July of 2003. This is a perfectly legitimate record of the disputes that occurred at that time to the IPCC report. — Cortonin | Talk 22:47, 8 Feb 2005 (UTC)

However, if INQUA booted him precisely because they wanted to repudiate his use of his authority to advance views that were at odds with the rest of the commission's membership, it would be a bit disingenuous of us to continue to do the same. If he's going to be quoted, I think he should be quoted as a single scientist, not as the representative of that body, since his views don't seem to be representative. Graft 00:02, 9 Feb 2005 (UTC)

The INQUA disbanded the entire commission, rather than simply remove him. The fact remains that he was the head of that commission, and he was clearly speaking from that position at the time he disputed the IPCC's sea level results, and he continued in that position for another three years after doing so. If you look at the current INQUA commissions [24], you'll see that they are no longer actively investigating sea level change, as per their statutes and bye-laws, they change the focus of the things they investigate closely every four years. In fact, if you check here, you'll see that the president of INQUA while Morner expressed his dispute with the IPCC conclusions is NOT the same as the current president of INQUA. It is this person who has spoken up adamantly against Morner, even though it seems this person had very little to do with the commission Morner was serving on. It seems this has much more to do with politics than with disputing Morner's work. — Cortonin | Talk 01:23, 9 Feb 2005 (UTC)

I've decided to step in and update the page to try and solve this conflict. Please check the new para. and see if it is to your satisfaction. —Ben 03:59, 9 Feb 2005 (UTC)

Weird. No one noticed the point I was making--that WMC's reasons for exclusion are POV.—Ben 00:27, 10 Feb 2005 (UTC)

Hmm.

• INQUA finally got sick of him, got rid of the commission, -- Source?
• http://www.pog.su.se/sea which is invalid: this commission doesn't exist anymore.
  • Click on "The Commission" and it says it ended in 2003. SEWilco 08:02, 9 Feb 2005 (UTC)
• The INQUA disbanded the entire commission, rather than simply remove him.
  • g.(i) The officers of a Commission and its subordinate bodies are elected for one inter-Congress period The INQUA didn't have to remove him, simply not reelect him. Where is their discussion of this? SEWilco
    • The INQUA was in the process of restructuring their commissions anyway, so there likely was not a formal discussion on that topic: [25]. (And thus, nothing should be implied here about him as a result of the commission no longer existing, because from the documentation it appears completely unrelated.) — Cortonin | Talk 15:54, 9 Feb 2005 (UTC)
• If you look at the current INQUA commissions [26], you'll see that they are no longer actively investigating sea level change
  • Try clicking on Coastal and marine processes and look for sea level. SEWilco
    • Ah yes, it appears there are still two smaller working-groups working on the topic in there. Leaders, and even members, of INQUA commissions are mandatorily rotated on a regular basis (with optional limited renewals for a term or two in some cases, see bye-laws for details). — Cortonin | Talk 15:54, 9 Feb 2005 (UTC)

The IPCC lists Morner as a TAR reviewer. Anyone know where they published reviewer comments? SEWilco 08:02, 9 Feb 2005 (UTC)

(William M. Connolley 17:00, 9 Feb 2005 (UTC)) Rather than having duplicate discussions, I suggest that sea level rise is the obvious place to discuss this. IPCC TAR reviewer is a near-meaningless status of itself.

Moved discussion to Talk:Sea level rise, and moved all references to sea level rise to sea level rise. (SEWilco 20:30, 9 Feb 2005 (UTC))

Data

I found this data ([27]) from NOAA, Mauna Loa, Hawaii, can anyone see the "raw" numbers?--213.238.212.98 13:42, 9 Feb 2005 (UTC)

Are you having trouble finding what you want when you click on Data at the top of that page? (SEWilco 20:40, 9 Feb 2005 (UTC))

Methane burps

The possibility of volatilization of methane caltrates is referred to in connection with past warmings, but it also has relevance to the discussion of competing views of feedback effects (damping down versus runaway). I therefore added a comment with a link in the "Greenhouse gas theory" section. This article has obviously benefited from a great deal of scientific expertise, so let me acknowledge that the link I added is to a popularization (from the Baltimore Sun), not a peer-reviewed journal article or the like. This kind of reference can be helpful to readers who (like me) aren't scientists. JamesMLane 07:16, 12 Feb 2005 (UTC)

Comparison of Temperature Reconstructions

I created this figure showing a comparison of temperature reconstructions for the Temperature_record_of_the_past_1000_years page. Since it could plausibly also be used on this page, I wanted to point it out here as well, but I'll let you guys decide whether or not you want to incorporate it.

Dragons flight 02:24, Feb 13, 2005 (UTC)

Role of water vapour

The artical is factually incorrect in many ways. I'll just touch on a couple of them. 1) Water Vapour is by far the most important green house gas. CO2 is not!

(William M. Connolley 10:11, 14 Feb 2005 (UTC)) You're wrong. This has all been discussed above. See-also: http://mustelid.blogspot.com/2005/01/water-vapour-is-not-dominant.html

---

No - You are the one who is mistaken. I read your blog and your explanation and I also read the other comments on water vapour here and indeed elsewhere as well.

Your argument does not hold water.

Just as in the case of the IPCC, the central part of your argument is that water vapour is short lived in the environment and hense it has its natural variation and any change will be rapidly restored to normal. This is true if you are looking at a single incident. If you look at this from the standpoint of a process then this is not the case.

Changes in the amount of H2O in the atmosphere can be constantly re-enforcing itself and these changes can be either natural or manmade.

(William M. Connolley 19:03, 15 Feb 2005 (UTC)) No not really. If humans emit lots of WV it just rains out again. To have a serious effect you would have to prevent evap, or cause excess evap, across substantial areas.

At the bottom of my post I tried to contrast the environment of today verses say the Cretaceous where the polar caps and the greenland ice sheets did not exist. Back then it was about 10C warmer on average than today. In addition there was about 50% more Oxygen than today.

I do not think that you can deny that with a 10C increment in temperature and the loss of the polar ice sheets that the atmosphere will hold a considerably increased amount of H2O. But I will ask - do you deny this?

(William M. Connolley 19:03, 15 Feb 2005 (UTC)) If you have some forcing agent - e.g. CO2 - warm the atmos, then you end up with more WV, which acts as a +ve feedback. Thats what I said.

I'm not trying to be personal. I am mearly trying to make my point.

Currently we have massive amounts of irrigatiion all over the planet and we are also releasing directly into the atmosphere a constant stream of H2O vapour. These factors are rather small on a global scale however. I doubt they have much influence but I am sure they do have some and especially we will be creating microclimates near our larger cities as a result. However - I would sort of doubt this might induce global warming.

(William M. Connolley 19:03, 15 Feb 2005 (UTC)) Err yes, thats what I'm saying - the anthro WV makes little difference.

That being said I think we should be taking a really close look at the amount of land area at high elevation and what the distribution of this land is. Every one of the previous ice ages ended at some point and it is not well understood why this might have happened. This is also true of the ice cycles of the say last 2.5 million years.

One possibility for the creation and distruction of the ice ages is the distribution of land masses relative to the poles and whether the poles are open ocean which cannot support a thick ice sheet or land which can. But combined with this if we have a large amount of land at high elevation we get a dry cold climate over that portion of the earth with a much greater loss of energy into space. This is the point I wanted to make. Let me be more specific: The Rocky Mountains for instance are anywhere up to 500 miles in width and at the end of the eocene the amount of land above say an elevation of 10,000 feet would have been considerably greater than today. This might represent say 15% of the total North American land mass. Although there was mountain building in the rockies in the Jurassic, the bulk of it came much later as the tropical sea that filled the Rockey Mountain geosyncline of the Jurassic and Cretaceous was replaced with an uplifted and not yet eroded alpine plateau that was destined to be eroded out to form the present ranges.

This would result in a considerable difference in the amount of energy reflected into space from this region. When we consider that europe and especially Asia/India/Tibet were also involved at a similar time with significant mountian building then I think it becomes clear that a considerable percentage of the incident solar energy falling on these continents could be reflected into space simply because a significant percentage of these contenants was at such a high elevation. A major part of this loss is due to the lack of water vapour at high elevation due to the temperature drop and its effect on the dew point. In addition we have the much greater reflectivity of the expected snow caps and glaciers in the high mountain areas.

In general - for a very controversial subject - the artical does read ok. However I feel the role of water vapour as the primary greenhouse gas should have a greater emphasis.

(William M. Connolley 19:03, 15 Feb 2005 (UTC)) I disagree, for the reasons stated above.

This does not mean that the role of CO2 as a manmade gas should not also have a promenant position.

(William M. Connolley 19:03, 15 Feb 2005 (UTC)) Since CO2 is the primary driver of current change, it should have (and does have) the primary position.

However, if one contrasts the climate of the cretaceous with the 80,000 PPM of atmospheric H2O possible in say a +45C tropical region to the say 30,000 PPM that we might expect today - then the changes in CO2 become insignificant. In fact - during the ordovician ice age the amount of CO2 in the atmosphere was about 19x greater than present and it was also much greater during the Carboniferous.

I think the way the artical reads should reflect this.

Thanx. Terrell

---

Much of the recent warming trends - if in fact this is a trend - could be due to increased atmopsheric H2O. Furthermore when one gets out of the apparently balenced H2O / climate which we arguably have now - some very powerful feedback mechanisms will cut in. In fact I would suggest the 10C plunge in temperature at the end of the Micocene is probably an atmosphere feedback mechanism which resulted in a cold dry climate in place of the hot moist climate which existed from say the Trassic to the Tertiary. (Many millions of years in fact).

While I have not yet been able to prove this - I'll post it here for discussion in case others wish to look for some proof.

At the end of the cretaceous we had quite a lot of land at very high elevation. The Deccan Traps covered much of western India - millions of square miles in fact. The Rocky Mountains as well as the Andies were pushed up - but not yet eroded away. Furthermore we had the Alps Pyrenes and Hellenic Mountains in Europe and again they were not eroded to the extent they are now.

Then India pushed into Asia creating the tibetian Plateau and the Himalayan Mountains. This was probably what pushed us over the cliff climate wise.

Lets consider the Cretaceous climate.

There was undoubtably more ocean and hense a greater percentage of the planet was able to absorb more incomming radation. Next Antarctica and the Arctic were not covered with ice and furthermore the Greenland Ice sheet would not exist.

The planet was about 22C average temperature at this time. If one checks the Absolute Humidity curves one can see that the dew point temperature climbs rapidly with temperature. This means that for instance the atmospheric H2O of a hot Cretaceous rainforest could be say 80,000 PPM (8%) if the temperature was say 45C.

Then if we look at the polar regions which were not frozen we could easily have say 5C and this could mean atmospheric water vapour at say 5,000 ppm (0.5%)

However consider the Himalayn Orogeny for instance. At an elevation of say 30,000 feet the temperature is going to be about -40C for much of the year. There would be a massive amount of glaciation and the attendant higher reflection of incomming radiation. At a temperature of -40C there is practially no water vapour. The curves of the absolute humidity are not detailed enough to read at these extremes.

What this means is that when enough land was sitting and high elevation and could cause the planet to start to cool - then we went over the cliff quickly and when the poles started to freeze over and hense dry out then the positive feedback of cooling -> lower dew point temperature -> reduced atmospheric H2O -> lower greenhouse gas levels -> more cooling kicked in and created our present snowball earth.

Clearly a large amount of land at high elevation as well as land at the poles can cause this tip into an ice world.

Over the last 30 million years we have lost a great deal of the land at high elevation due to erosion. The Himalain Orogeny is still continuing however.

It is possible that we have once again passed the point of no return - in which case if we start to warm up humidity may start to increase and we may lose the polar ice. I think Anarctica is quite a ways from this point at present mind you. How about the Greenland ice sheet? The North Polar ice cap can go and if so then humidity will rise and the amount of retained energy will increase.

In short we could see a relatively rapid rise in temperature.

If anyone wishes to do a GOOGLE search for say "water Vapour Global Warming" they will see there are over 100,000 articals on line. Here is onc from Physics Web.

http://physicsweb.org/articles/world/16/5/7

Here is a short quote:

"...carbon dioxide has received a bad press for many years and is uniformly cited as the major cause of the greenhouse effect. This is simply not correct. While increases in carbon dioxide may be the source of an enhanced greenhouse effect, and therefore global warming, the role of the most vital molecule in our atmosphere - water - is rarely discussed. Indeed, water barely rates a mention in the hundreds of pages of the 2001 report by the Intergovernmental Panel on Climate Change."

The IPCC in Chapter 7 explains why they did not include water vapour in the model. The issues is that when the vastly most significant variable is eliminated - which is equivalent to setting it to zero - then the model will have little value.

To summarize what I am saying.

CO2 levels are about 365 PPM H2O levels are as follows:

Eastern Seaboard of North America - mid summer: 35C => 30,000 PPM Western Europe mid summer: 35C => 30,000 PPM South East Asia / India / Amason: 40C => 40,000 PPM

Water vapour is a stronger absorber than CO2 and there is far more of it.

It is my opinion that irrigation will have a pronounced effect as well. Water that would normally flow to the ocean in a thin ribbon is now forced into the atmosphere via transpiration and rains on otherwise arid soil where it once again enters the atmosphere. This will increase the overall absolute humidity which will result in increased heat retention. OTOH, distruction of the rain forests will have the opposite effect - Ie - global cooling.

Terrell,

I don't object to your attempting to discuss whatever issues you feel are appropriate, but in terms of potential changes to the article, I would direct you to the Wikipedia's policy on no original research. Basically, it says that theories and interpretations of facts should only be included in Wikipedia if they are derived from notable external sources. Which in our context basically only means those theories that have been proposed by scientists within the context of the published peer-reviewed scientific literature.

Some of the issues you discuss (e.g. the importance / unimportance of water vapor) obviously have been argued within the scientific literature, and hence may be suitable for discussion in Wikipedia. Other of the ideas you propose (e.g. the importance of uplift) appear to be original to you, at least as far as I am aware, and hence would not be suitable for Wikipedia.

I don't want to discourage you from discussing and thinking about these issues, but I do want you to understand the nature of Wikipedia. If you want to inject unusual minority viewpoints into a scientific article on Wikipedia, it is really only possible if you can provide rigorous documentation of supporters within the published, peer-reviewed scientific community. The physicsweb article you mention is a small step in that direction (at least in the context of water vapor), but it is not adequate since it is not peer-reviewed.

Dragons flight 15:09, Feb 15, 2005 (UTC)

I don't think the uplift theory is original to Terrell. Although it is probably mentioned in the discussion sections of journal articles rather than being the main topic.--Silverback 15:32, 15 Feb 2005 (UTC)

Moberg publication in Nature

Evidently Nature did not want McIntire and McKitrick to get credit for killing the hockey stick. They had to beat them to the punch.--Silverback 18:10, 15 Feb 2005 (UTC)

(William M. Connolley 18:58, 15 Feb 2005 (UTC)) You're probably premature in that, but no matter for now. I would like to move your nice new text about Moberg over into the last-1-kyr page. With the new pic of the various reconsructions its now clear that there are plenty of versions, so it seems appropriate to have the discussion on that page.

Certainly these results should be discussed in detail on that page, however, I think the signed feature story in Nature [28], where most of the scientist quotes are from (there are more there), make it clear that these results have implictions in the global warming debate. IPCC is criticised for putting so much emphasis on the Mann hockey stick, and there is discussion of how IPCCs credibility will probably suffer. Technically, the scientists are correct that this new understanding does not effect the relative attribution to human influences of the recent warming. However, the credibility of the fear mongering relied heavily on what the hockey stick portrayed as warming unprecedented in human history. I think the text I have in this article should remain. The hockey stick was that central to the political part of the debate, and I think it influenced the level of alarm that scientists raised as well. A note or two on McKitrick should be added when that comes out. There should be some pronouncements at that time or after the may IPCC conference in May of the death of the hockey stick. --Silverback 19:53, 15 Feb 2005 (UTC)

OT Remark: This page is getting huge. Maybe it's time that somebody adept at the technical aspects creates a new archive page? On topic again: As far as I can see, Moberg et al are still within the 2 sigma confidence interval of Mann et al. So it is not revolutionary. Of course, the public usually only sees a much simplified version. But, for a moment, assuming Moberg et al are correct, the warming is still unprecedented. The actual temperature may (or may not) have been similar in the MWP, but the rate of change is unprecedented, as far as I can tell. --Stephan Schulz 14:50, 16 Feb 2005 (UTC)

(William M. Connolley 16:25, 16 Feb 2005 (UTC)) I've archived about 1/3 of it. I disagree with just about all that Silverback said.

I don't think there is enough precision in the reconstructions to say that today's warming is unprecented, especially when the confidence intervals are taken into account. The key implication of the Moberg, et al, and Von Storch, et al is that centenial scale variability is much larger than previously thought, and with the sample being only 10 centuries, the current warming may well be within the natural variability of the current interglacial period. The statements praising Mann's groundbreaking (if technically incorrect) attempt at a global reconstruction and implying that the post 1990 warming may be greater than the Medieval warm period are SOPs thrown to the climate community to make this bitter pill easier to swallow and spin. Combine this uncertainty with the poor current understanding of possible cloud and aerosol feedback mechanisms, and there is reason to be conservative instead of sacrificing hundreds of billions of dollars of wealth.--Silverback 12:36, 17 Feb 2005 (UTC)

(William M. Connolley 13:55, 17 Feb 2005 (UTC)) *You* may not think there is anough precision, but all the climatologists quoted - including von S - think otherwise. Describing them as sops is fine in talk as your own personal POV, but please don't put it into the article.

I don't have any intent to put my personal opionion regarding their intent into the article. I hope it was clear that I was describing the statements and not the persons as SOPs.--Silverback 14:35, 17 Feb 2005 (UTC)

(William M. Connolley 17:34, 17 Feb 2005 (UTC)) OK. I disagree, of course: I see no reason to believe that the statements were sops (incidentally, are we talking about the same thing? You are capitalising SOP as though it were an acronym... I mean sop, as in the thing you fling to the dogs or somesuch).

I think that the use of "SOP" as an acronym for "Standard Operating Procedure" originated in the U.S. military, though I'm not sure. Silverback's use, however, appears to be "sop" in the common English word sense. JamesMLane 20:53, 17 Feb 2005 (UTC)

A SOP is wetter, heavier and louder when it hits the dogs than a sop. My bad.--Silverback 14:24, 18 Feb 2005 (UTC)

organizational

This should be pretty non-controversial.

The six-page bottom section of this page is really ugly. Can some of these links be cleaned up? Are all of them really necessary?

Also, it's pretty obvious that this is a super-meta-topic, and ought to be organized that way. Anyone want to put together a topic template for global warming/climate change topics? Graft 06:07, 16 Feb 2005 (UTC)

Note the controversial label at the top. The way to reach consensus is to be able to cite supporting literature and let everybody have their documented say. The scientific field is going through a lot of turmoil right now, so it is best to wait until things shake out before reorganizing. There is the possibility that there may be lull this summer.--Silverback 08:54, 16 Feb 2005 (UTC)

Recent edits by JonGwynne

Hi Jon. There is not enough space is the summaries, so let me explain my position here. There are three different things in your edit, all of which I disagree with. First, you insist on the "steadily falling" temperatures in the mid-20th century. Looking at the temperature graph, there is nothing steady about it. Of course you can cherry-pick start and end dates to get a "long" downwards trend, but the longest steady drop is about 10 years. The overalll trend is clearly and overwhelmingly upwards, and stating something different is at least misleading.

Secondly, you inserted the water vapour in a way that suggests that CO² does not matter. Your addition is not technically wrong, but again misleading, and adds no useful information.

Finally, you removed the - in my opinion - relevant and useful information on the climate model.

I will revert you again now (unless someone else preceded me), please discuss these points. --Stephan Schulz 02:30, 17 Feb 2005 (UTC)

Reverted JGs revert. Come on Jon, discuss a bit - what are your reasons. I agree with Stephan. Vsmith 03:29, 17 Feb 2005 (UTC)

Sorry, I thought I'd commented on this. My repy seems to have vanished. Oh well, I'll try to remember what I said...--JonGwynne 20:57, 18 Feb 2005 (UTC)

If I described the temperatures during the cooling periods in the 20th century as "steadily falling", then I apologize. I shouldn't have, because they didn't fall steadily from year to year (though, to be fair, the cooling trend over the 30+ years of the event was a steady one). I have no problem with coming up with compromize language that we can all agree on - that's what I always thought the point of wikipedia was. Occasionally, you get guys like WMC who ruin it by adopting the "revert-boy" mentality. But that's beside the point. The point is that we should work together and come up with a description of the cooling trend that we can all agree is accurate. Tell you what, if one of you want to "take point" on this and replace my description with one of your own, that would be fine with me. Or if you would prefer to edit mine, that's OK too.--JonGwynne 20:57, 18 Feb 2005 (UTC)

re CO2. I don't believe I implied that it "does not matter", but it is important to put CO2 in its place as regards the effect it has on global warming. It is not the most powerful greenhouse gas and I think it is important to say that clearly because there are a lot of people who think that it is the sole cause of global warming and that simply isn't correct.--JonGwynne 20:57, 18 Feb 2005 (UTC)

The paragraph that begins "if the only variable considered" is worthless. It doesn't mean anything to only consider the one variable so there's no point in talking about what would happen if someone did.--JonGwynne 20:57, 18 Feb 2005 (UTC)

p.s. Hey Marco! Read the damn talk section BEFORE you revert. You might learn something.--JonGwynne 20:57, 18 Feb 2005 (UTC)

(William M. Connolley 22:07, 18 Feb 2005 (UTC)) I see that JG is now calling for discussion before reversion - what a nice idea. So:

Global average temperatures have risen steadily (0.6 ± 0.2°C) since that time apart from a period in the mid 20^th century in which global temperatures fell just as steadily

This is wrong. Its perfectly clear from the record that the fall was much milder.

I agree. So, let's stay away from characterizing the nature of the changes and simply note that they took place.--JonGwynne 22:52, 18 Feb 2005 (UTC)

Though the majority of the greenhouse effect is caused by water vapor which is non-anthropogenic.

This is true, but misleading and irrelevant, so shouldn't be there. This point may not be immeadiately obvious: so (to others; JG knows this already) see my http://mustelid.blogspot.com/2005/01/water-vapour-is-not-dominant.html.

Explain how something can be true but misleading... The fact is that the majority of the greenhouse effect is caused by water vapor. You may not like that fact but it remains a fact. Your blogs are irrelevant. and articulates many problems with the IPCC's use of climate models . Your editorial views are of no interest to anyone who doesn't already agree with you.--JonGwynne 22:52, 18 Feb 2005 (UTC)

The fact is that the majority of the greenhouse effect is caused by water vapor is correct. But that paragraph deals with global warming, not the greenhouse effect. According to all remotely scientific models, the root cause for the current global warming is an increase in CO₂. Since many people confuse these two concepts, mentioning the relatively small direct part of CO₂ in the greenhouse effect is misleading. It belongs into the greenhouse effect article.--Stephan Schulz 23:55, 18 Feb 2005 (UTC)

(William M. Connolley 23:02, 18 Feb 2005 (UTC)) True but misleading is an easy concept. The link explains it in detail. Blogs are irrelevant... no. Not at all reasonable. That blog contains reasoned argument, which you don't like, but can find no counter to.

If it is an easy concept, they it should be easy for you to explain here. I've read your blog. It was unremarkable. There was nothing to counter, it was simply idealogical wool-gathering - assumptions and musings without foundation... useful for chatting up an Greepeace babe at a party but not much else. Sorry. --JonGwynne 23:20, 18 Feb 2005 (UTC)

If the only variable considered is the emission of greenhouse gases related to human activity, then climate models predict that temperatures will increase in the future; however, the precise magnitude of these increases is still uncertain [29], with a range of +1.4°C to +5.8°C for the temperature change between 1990 and 2100. Much of this uncertainty results from not knowing future CO₂ emissions, but there is also uncertainty about the accuracy of climate models and it is not clear if they under- or overpredict future climate change.

This paragraph explains that T is predicted to rise in the future; an article on GW that didn't mention that, and give a range of values, right at the start would be very odd indeed.

It is still a meaningless paragraph. First, there is no way to "only consider anthropogenic greenhouse gasses"

(William M. Connolley 23:02, 18 Feb 2005 (UTC)) Of course there is, because the para is about models, where you can do exactly that.

How? Explain how the percentage of greenhouse gasses are accurately determined and what that number is.--JonGwynne 23:20, 18 Feb 2005 (UTC)

because there is no way of determining which portion of greenhouse gasses are anthropogenic. Each CO2 molecule doesn't come with an identifying tag. The best that can be done is to guess about what percentage of the greenhouse gasses are anthropogenic and, to quote Michael Crichton just because it annoys you, "guesses-just so we're clear-are merely expressions of prejudice". Perhaps you can explain why we should take the word of scientists who can't predict what's going to happen next week for what is going to happen in a hundred years.

(William M. Connolley 23:02, 18 Feb 2005 (UTC)) Confusing weather and climate won't help you.

Just as confusing "glib" and "cogent" won't help you. A guess is a guess and climate models aren't fact.

You're falling into the classic Paul R. Ehrlich trap. He was another scientist who made all sorts of doom-laden predictions by projecting current trends into the future with no real understanding of what controlled those trends. He isn't taken seriously anymore as a prognisticator (at least not by anyone with an ounce of common-sense) so why do you think it is going to be different for the IPCC brigade? --JonGwynne 22:52, 18 Feb 2005 (UTC)

(William M. Connolley 23:02, 18 Feb 2005 (UTC)) As to credibility: please note that JG made this edit [30] and labelled it "copyedit" - a clearly deceptive edit comment.

Please note that WMC refused to address the issue at hand, preferring to whinge about complaints that exist only in his head.

Note - the read in my recent edit summary was an ambiguous usage, could mean two different things. I meant that I have read the above discussion and still see no reason for JGs changes. Sorry about the ambiguity. -Vsmith 00:51, 19 Feb 2005 (UTC)

Wikipedia:Requests for arbitration/JonGwynne

(William M. Connolley 00:10, 19 Feb 2005 (UTC)) Note: I have filed Wikipedia:Requests for arbitration/JonGwynne, in part for his edits to this page.