Reply was ill-informed (From Bucks Free Press)

This is such a fantastically weird letter! I always get a chuckle from Mr Alexander's rants, but this is a classic!

Bill Williams wrote:
This is such a fantastically weird letter! I always get a chuckle from Mr Alexander's rants, but this is a classic!

It seemed to me that he was crediting you with enough intelligence to need only a pointer towards the sort of information for which you ought to be looking. I guess he was over-estimating your intellectual rigour, which after our last exchange doesn't surprise me.

How delightfully mature. I can see I made the wrong decision in disengaging from our last discussion. Oh well, live and learn.

Ooh, sarcasm.. how cutting. And hypocritical, given your previous comment. I can see why you stopped our previous discussion, though: being shown to be wrong at so many levels must have been a bit hard to take.

Such anger! If it wasn't for the lack of terrible puns every other sentence, I would think you were the Carbon Coach in disguise.
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Tell you what, in an attempt to calm things down, I'm going to attempt to discuss Mr Alexander's letter and exactly why I find it so amusing.
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Firstly, I never claimed that the global warming debate had quietened down, I noted that it had dropped off on every recent poll of public concerns. I wouldn't mind, but, my letter was about 6 lines long and he still missed the point.
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Secondly, I have no interest in lobby groups on either side of any debate. The position of Heartland or Greenpeace etc have no relevance. To bring them up is bizarre in the first place. To consider them a gauge of the state of the debate is just confused.
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Even then, did Mr Alexander, apparent king of internet searches, fail to read about the leaked UEA emails and the ensuing mess? Hide the decline, Mann's dirty laundry? The entire Briffa divergence problem? I've never seen him write a letter even acknowledging these events, let alone imploring readers to google for it. It's all rather amusingly one-sided. But I digress.
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Finally, slightly back towards the point my letter raised, we are treated to the patrons list of "Population Matters". Unfortunately, considering the Royal Society's motto 'Nullius in verba', I was disappointed that Mr Alexander failed to appreciate the irony of an appeal to authority as a "closer" to his argument.
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The fact that James Lovelock, who recently dissented from his previously alarmist position over global warming, is present on the list is just a cheeky bonus.
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That is why I found it "fantastically weird", but then, considering he has previously stated that his daffodils proved anthropogenic global warming, I shouldn't be surprised.

That is why I found it "fantastically weird", but then, considering he has previously stated that his daffodils proved anthropogenic global warming, I shouldn't be surprised.

I can't help but wonder, are you intentionally misrepresenting or have you simply misunderstood? Seeing as you are not the only person on these pages to have attempted ridicule based on one or the other, I'll try and explain so that you might try to be a bit more polite in future.

As I understand it, Eric's observation is that daffodils locally have been coming into flower earlier and earlier in the year over a period of decades. The deduction from this is that locally there has been an average increase in temperature - this, on its own, does not prove global warming, nor the anthropogenic nature of the warming; however, it is an observation which has been repeated across the UK, so it's not a purely local phenomenon.

The increase in temperature on a global scale is very small compared to the fluctuations in temperature we experience on a daily basis, so there aren't many things you can see or measure without instrumentation which are evidence of an ongoing trend towards higher temperatures - the point where daffodils come out each year is actually quite an elegant example.

It doesn't on its own prove AGW, nor is that what is claimed; however, it is another data point in an ever-increasing set which overwhelmingly point the same way.

Even then, did Mr Alexander, apparent king of internet searches, fail to read about the leaked UEA emails and the ensuing mess? Hide the decline, Mann's dirty laundry? The entire Briffa divergence problem? I've never seen him write a letter even acknowledging these events, let alone imploring readers to google for it. It's all rather amusingly one-sided. But I digress.

If the leaked UEA emails made any substantial difference to the underlying data, you might have a point. As it is, it's a bit like Rev. Peter Jackson talking about "missing transitional fossils" disproving evolution - don't look at what isn't there, look at what is and where the data points. The real shame of the words used in those leaked emails is that it has allowed people like you to make a lot of noise, distracting attention from what the almost overwhelming quantity of data shows.

For that sort world view to be correct, there would need to be possibly the world's biggest conspiracy *ever*, with scientists from all over the world lying either about what the data are or what the interpretation is - you obviously don't know that many scientists if you think that's a viable option. The tide of scientific consensus may seem like it at times to the uninitiated, but that's because when the data nearly all points one way, there is only one reasonable conclusion to be drawn - it's not conspiracy, it's data-backed logic.

Secondly, I have no interest in lobby groups on either side of any debate. The position of Heartland or Greenpeace etc have no relevance. To bring them up is bizarre in the first place. To consider them a gauge of the state of the debate is just confused

To be honest, I find lobby groups on both sides of the debate an unhelpful distraction, too, and definitely wouldn't have used them as examples if I'd written myself. However, given that your last letter and comments supporting it contained inaccuracies and fallacies, you're not really in a position to take some kind of high ground and call it "bizarre".

Firstly, I never claimed that the global warming debate had quietened down, I noted that it had dropped off on every recent poll of public concerns.

Fair point. However you did say:

the environmentalist position has now shifted to Malthusianism.

..which does imply that the debate itself has moved on. Even if that implication seems to be a fantastic generalization from one letter based on one report to a wonderfully sweeping statement about "the environmentalist position".

Such anger!

Anger? Not exactly. You wouldn't like me when I'm angry... http://tinyurl.com/c
9dgy8j

Where to begin. Hmmm. Let's start here.
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"It doesn't on its own prove AGW, nor is that what is claimed; however, it is another data point in an ever-increasing set which overwhelmingly point the same way."
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So the daffodils don't prove an anthropogenic signal, yet they were raised in a debate over the proof of an anthropogenic signal. But they are still relevant because they show a regional warming? Even though no-one was debating that there has been warming over the 20th century? That's pretty tenuous.
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Anyway, moving on. Ah, yes, the UEA emails.
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"The real shame of the words used in those leaked emails is that it has allowed people like you to make a lot of noise, distracting attention from what the almost overwhelming quantity of data shows."
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The emails were more than a "use of words", they showed:

- The admission of the divergence problem in the Briffa proxy series and the intended method "hiding the decline" in the proxy from the instrumental record, so as not to "cloud the message" for the AR4.

- The value of Mann's R2 statistics (the so called "dirty laundry") which he fought hard to prevent from divulging when requested. Which is understandable because they showed awful statistical significance in his results.

- The revelations over the Yamal proxy, the difference in the updated and older versions and the obvious attempt to prevent McIntyre from accessing the updated data.

- The intentional deletion of emails which were requested under FOI act.

None of this requires a conspiracy of any size, let alone the world's biggest. It is merely the occurrence of a common phenomenon within science; groupthink. Look at the co-author matrix on pages 2 and 3 of the Wegman discussion of his report (1) to see how this has evolved. His comments regarding the perversion of peer review within climate science are even more interesting considering the recent Gergis 2012 embarrassment.
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To attempt to write all this off as some inconvenient word usage is not very convincing.
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Um, okay, finally we have...
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"..which does imply that the debate itself has moved on."
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Nope, it implies that that is an entirely different debate because the last one wasn't working out so well. My statement wasn't based purely on one letter, that's speculation. I commented because I found it interesting that across the whole spectrum of environmental reporting, the emphasis was being clearly shifted off of "anthropogenic CO2 drives the climate so we need to de-industrialise" to "there's too many people, so we need to de-industrialise". Mrs Carter's letter was just "another data point in an ever-increasing set which overwhelmingly point the same way", as you say.
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I'm embarrassed to admit this, but I don't have any cool, self assured cartoons to tag on the end here. I'll have to sort something out for the future.
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(1) http://www.uoguelph.
ca/~rmckitri/researc
h/StupakResponse.pdf

So the daffodils don't prove an anthropogenic signal, yet they were raised in a debate over the proof of an anthropogenic signal. But they are still relevant because they show a regional warming? Even though no-one was debating that there has been warming over the 20th century? That's pretty tenuous.

If I remember correctly, the first mention of the daffodils came in a letter to the BFP not in a debate that was specifically limited to proof of the anthropogenic nature of an agreed global warming. Your attempt to characterise it otherwise is disingenuous.

There are several points where people denying AGW argue against the consensus in the scientific community:
* That no warming is occurring at all
* ..or if it is, it's completely conisistent with historical warming/cooling cycles
* ..or if it is unlike previous planetary warming, it has nothing to do with mankind
* ..or if mankind does have something to do with the observed warming, it's not significant

In any argument about AGW, if people don't accept there is any warming, then showing a simple, easily visible example of a year-on-year warming effect is an appropriate starting point.

From your quote above, before we go any further can I take it that you agree that warming is occurring, but you are sceptical that mankind has anything to do with it? i.e. where would you place yourself in that list above?

across the whole spectrum of environmental reporting, the emphasis was being clearly shifted off of "anthropogenic CO2 drives the climate so we need to de-industrialise" to "there's too many people, so we need to de-industrialise"

Really? I read the Telegraph daily, the Guardian two or three times a week, the BBC and a few others online most days, listen to the Today programme, watch BBC or ITV news nearly every day and was completely unaware of this seismic shift in the whole spectrum of environmental reporting. Which ever-increasing data set would that be, then?

Since the last link went down so well, here's another one for you: http://tinyurl.com/v
6bgx

PS.. something has just occurred:

"there's too many people, so we need to de-industrialise"

..I'm not aware of anyone phrasing things in those terms, well, ever. Especially as the more industrialized nations have considerably lower birth rates and generally produce more food than their less-industrialized counterparts.

"If I remember correctly, the first mention of the daffodils came in a letter to the BFP not in a debate that was specifically limited to proof of the anthropogenic nature of an agreed global warming. Your attempt to characterise it otherwise is disingenuous."
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I would question your recollection of that debate. It was between Mr Weeden and Mr Alexander over several months via the BFP letter pages. The former agreed that there had been some modest warming in the 20th century, but was not convinced it was entirely anthropogenic nor leading to a disaster. Mr Alexander failed to differentiate between an observed warming and the attribution of an anthropogenic cause of said warming, hence the rather amusing daffodil letter and a fallback position of emoting over "the children" and "the children's children".
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"where would you place yourself in that list above? "
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Firstly, "denying AGW" isn't particularly great language. If I continue to answer your question without comment to this, I would be implicitly agreeing that there is some kind of "fact" which I am "denying". Further to that there is the obvious extraction from "climate denier" which carries obvious, usually intentional, connotations.
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A better way to phrase it is "why are you sceptical?", which is how I will answer.
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I'm not aware of any (serious) sceptic of AGW who claims there has been no warming. Surface records and satellite measurements both show that there has been a modest warming (about 0.7 degrees over the last century).
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Considering that anthropogenic CO2 is assumed to have caused around half the observed warming, it's interesting to note that there has been no significant warming for around 15 years now (statistically speaking), while CO2 levels have been continually increasing over this time. This, coupled with the lack of required ocean warming (Trenberth's infamous 'missing heat'), creates some interesting questions as to the falsification criteria for the AGW hypothesis i.e. considering that for each year there is no net warming the next must, logically, see even greater warming, for how long does the lack of warming have to persist before the AGW hypothesis is falsified?
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But I digress. Primarily, the debate comes down to feedbacks and the sensitivity of the climate. CO2 can only cause so much warming due to it having a fixed transmission spectrum, thus giving a logarithmic response under increasing concentrations. This is generally agreed to be ~0.5-1 deg C for a doubling of present levels and does not, therefore, cause significant concern of planetary disaster.
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Thus, a multiplying factor must be applied in order to achieve several degrees of warming. This, it is argued, comes in the form of positive feedbacks within the climate system which amplify or "force" the initial, minor warming. This is the IPCC position.
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Here is where we find the debate. It is not even agreed as to what the correct way to measure climate sensitivity is. Or if it can ever be measured accurately enough to make predictions.
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The IPCC argues that since climate models cannot accurately hind-cast the modern warming without a large climate sensitivity (the majority of this "forcing" is said to be from increased water vapour), it must therefore exist. This is incredibly circular logic considering that said models cannot even replicate clouds (because we don't even fully understand how they interact with the climate system yet). To assume that we can derive the constants of a system from an incomplete model of said system isn't particularly convincing.
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It is primarily this lack of understanding of the water vapour/cloud factor within the climate system that has caused the IPCC to hugely overestimate the sensitivity of the climate e.g. (1),(2). Although there are a multitude of oversights and leaping assumptions within the IPCC AR4, this is one of the largest.
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I'm aware that this post is already too long and I've waffled a bit (you did ask!), so I'll leave my position outline there.
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Um, I supposed I owe you a link. Here:

http://tinyurl.com/b
wfrw

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(1)
http://www.nature.co
m/nature/journal/v46
3/n7280/full/nature0
8769.html

(2)
http://www.sciencema
g.org/content/327/59
70/1219.abstract

I would question your recollection of that debate. It was between Mr Weeden and Mr Alexander over several months via the BFP letter pages. The former agreed that there had been some modest warming in the 20th century, but was not convinced it was entirely anthropogenic nor leading to a disaster. Mr Alexander failed to differentiate between an observed warming and the attribution of an anthropogenic cause of said warming, hence the rather amusing daffodil letter and a fallback position of emoting over "the children" and "the children's children".

You have a far kinder recollection of Mr Weeden's position than mine: Anthony Weeden repeatedly misinterpreted or misrepresented what Eric Alexander had written, either through a lack of understanding or because he was being disingenuous (how many of the latter's letters involved explaining why what the former had said about his previous letter was incorrect?)

Why do you (and he) repeatedly present the daffodil example as "a daffodil proves anthropogenic global warming" when that is not what he has claimed?

Both you and Anthony Weeden have gone the reductio ad absurdam route of turning a reasonable and appropriate observation into a silly strawman then pointing and laughing. Then you have the hypocrisy to call Eric Alexander out for name-calling. Though the strawman shouldn't surprise me: that's exactly what you were doing on the other comments thread.

I'm not aware of any (serious) sceptic of AGW who claims there has been no warming. Surface records and satellite measurements both show that there has been a modest warming (about 0.7 degrees over the last century).

You call a rise of 0.7 degrees "modest", yet over a period of 100 years has temperature *ever* risen that much before? Certainly none of the proxies for temperature change show anything like that sort of speed (given that global temperature measurement hasn't been around for long enough to use any other way of estimating temperature).

for how long does the lack of warming have to persist before the AGW hypothesis is falsified?

Seeing as there has (from your own comment above) inarguably been warming, either there is no anthropogenic portion at all in the largest 100-year jump in temperature, or the AGW hypothesis is proven: there has already been anthropogenic global warming.

The planet has an almost uncountable number of positive and negative feedback mechanisms, either buffering or amplifying the temperature change, and I don't think we'll ever get to the point where you can look at the modelling and say "that's 100% correct"; however, and this is what I think you fail to understand, the models being used are the best approximations we have at the moment. Come up with a better explanation for that "modest" 0.7 degree rise and it will in time become the scientific consensus.

The climate debate shouldn't be an "I'm right"/"You're wrong" sort of argument, because it's way, way too complicated for that. The IPCC have made errors - show me a scientist who claims never to have - but none of them highlighted so far come close to overturning the current orthodoxy. The parallels with creationists trying to overturn the theory of evolution by pointing to incompleteness in the fossil record are really rather striking.

As for your linking to linking to articles on falsifiability and social network connetions between peer reviewers (the latter presumably to back up your dismissal of the entire climate scientific peer review process as "groupthink" - tell me, do you believe that the scientific consensus around evolution is also "groupthink" and erroneous?), how do you think the current consensus was arrived at in the first place?

"You call a rise of 0.7 degrees "modest", yet over a period of 100 years has temperature *ever* risen that much before?"
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Looking at the data (and this is just one example, there are doubtless others) 1860-1960 (1).
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But that is largely irrelevant if the question is: are we seeing something unprecedented with regard to the rate and scale of the warming?
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Looking at the scale of the warming, the majority of the paleo evidence shows that the "medieval warm period" was warmer than today. So the scale of the warming is not unprecedented.
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Looking at the rate, we don't need proxy data to see that the warming observed across 1860-1880, 1910-1940 and 1975-1998,1975-2010 are all ~0.15 degrees per decade (2). So the rate of the warming is not unprecedented.
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As I mentioned before, the only way an attribution to mankind can be made is by taking the warming due to the additional anthropogenic CO2 and amplifying it with assumed positive feedbacks (primarily from clouds). Without these modelled feedback parameters, the models cannot hind-cast the warming from 1975 onwards.
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This is key, as I believe this is where you are becoming confused.
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The term "AGW hypothesis" does not refer simply to the hypothesis that anthropogenic CO2 causes warming. It also includes the extended part of the argument which are these assumed positive feedbacks and an eventual runaway warming event which will be catastrophic.
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That the transmission spectrum of CO2 contains absorption bands in the infra-red is not disputed.
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That increasing the concentration of CO2, therefore, will obviously result in some level of warming is not disputed.
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What is disputed is that the attribution of the entire modern warming of 0.7 degrees (which yes, is modest) solely to man is based on ignorance rather than evidence. Even the infamous Phil Jones had to admit that the biggest factor convincing him of an anthropogenic cause was...
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"The fact that we can't explain the warming from the 1950s by solar and volcanic forcing"
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....which is hardly a convincing reason. Effectively saying "because I can't think of anything else" when the climate system has, by your own admission, an unknown number of unknown feedbacks, isn't exactly the "science is settled" consensus which we've been told about.
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To make a point, a 1-2% reduction in cloud cover over the past 30 years could be enough to cause the observed warming. Such a decrease has indeed been observed, in spite of the proposed positive feedback between clouds and climate(4).
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I agree that the models we have are the "best approximations we have at the moment". However, your attempt to extend this to an argument that they cannot, therefore, be incorrect is illogical. The biggest disconnect between the models and reality are clouds. Yet this is the largest, assumed, positive feedback used to align model output with reality. And this is without going into the mess of things like "flux adjustments" to help get the correct answer.
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This is what is under debate and the lack of warming over the past 15 years, while CO2 has continued to rise, has only added to the interest.
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N.B. I don't consider your comments or questions regarding evolution relevant or honest so I've purposefully ignored them. An attempt to align me with creationists only weakens your argument.
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(1) http://www.woodfortr
ees.org/plot/hadcrut
4gl/from:1860/to:196
0

(2)
http://www.woodfortr
ees.org/plot/hadcrut
4gl/every

(3)
http://news.bbc.co.u
k/1/hi/8511670.stm

(4)
http://www.ann-geoph
ys.net/30/573/2012/a
ngeo-30-573-2012.htm
l

Looking at the data (and this is just one example, there are doubtless others) 1860-1960 (1).

You have picked a single post-industrial example which overlaps more than half of the temperature rise I was talking about. There are "doubtless others"? Go on, find one.

Looking at the scale of the warming, the majority of the paleo evidence shows that the "medieval warm period" was warmer than today

No it doesn't. Go back and check your "facts".

The term "AGW hypothesis" does not refer simply to the hypothesis that anthropogenic CO2 causes warming. It also includes the extended part of the argument which are these assumed positive feedbacks and an eventual runaway warming event which will be catastrophic.

You seem to be making a habit of mis-stating the view you're arguing against in order to make it easier to argue against. In this case, you're conflating the measurements and inferences from that (that temperature over the past century and a half has risen unprecedentedly steeply, and the inference that mankind was at least in part causal in that temperature rise) with the mechanism - CO2/CH4 as greenhouse gases, mankind's massive energy output, pollution.

Even the infamous Phil Jones had to admit that the biggest factor convincing him of an anthropogenic cause was...

"had to admit".. Your showing your prejudice, here. In the absence of anything else to explain the warming that has been measured, what would *you* say has caused it?

It's kind of how science works, though - in this case, looking at an effect and see if you can work out what has caused it. In the absence of a huge increase in energy input, or anything global, you look at what else has changed and see if there's a chance that one effect has caused the other - hence the focus on mankind's output of greenhouse gases as something that has changed markedly over the past century, and can be shown experimentally (if somewhat simplistically) to cause warming.

To make a point, a 1-2% reduction in cloud cover over the past 30 years could be enough to cause the observed warming. Such a decrease has indeed been observed, in spite of the proposed positive feedback between clouds and climate(4).

OK, I'll bite... You claim a "a 1-2% reduction in cloud cover over the past 30 years could be enough to cause the observed warming" unsourced, but link to an article which shows that there has been a reduction in cloud cover in China.. Regarding your first assertion, if you look a bit deeper rather than accepting at face value what you read on wattsupwiththat.com, you'll find it's a lot more complicated than that (http://journals.ame
tsoc.org/doi/abs/10.
1175/1520-0469%28197
2%29029%3C1413%3ACAA
GCF%3E2.0.CO%3B2); regarding changes in cloud cover, you'll also find that it's a lot more complicated than that, too (http://journals.ame
tsoc.org/doi/pdf/10.
1175/JCLI4031.1).

In other words, it's overly simplistic to say a 1-2% reduction in cloud cover could cause the observed warming; and globally that reduction of cloud cover hasn't happened so the point is moot. In that second article it does show large regional differences, so looking at a single area (even one as big as China) is not significant.

I agree that the models we have are the "best approximations we have at the moment". However, your attempt to extend this to an argument that they cannot, therefore, be incorrect is illogical.

It would have been illogical if that is what I had said. You've mis-stated my position - this is getting to be a bit of a recurring theme, isn't it?

N.B. I don't consider your comments or questions regarding evolution relevant or honest so I've purposefully ignored them. An attempt to align me with creationists only weakens your argument.

Dishonest? That's fairly rich coming from someone whose main arguments are nearly all against something nobody else is saying. Maybe, instead of getting all huffy and indignant, you ought to look to your debating style and not behave in a way which makes such comparisons appropriate.

philbo wrote:

Looking at the data (and this is just one example, there are doubtless others) 1860-1960 (1).

You have picked a single post-industrial example which overlaps more than half of the temperature rise I was talking about. There are "doubtless others"? Go on, find one.

Looking at the scale of the warming, the majority of the paleo evidence shows that the "medieval warm period" was warmer than today

No it doesn't. Go back and check your "facts".

The term "AGW hypothesis" does not refer simply to the hypothesis that anthropogenic CO2 causes warming. It also includes the extended part of the argument which are these assumed positive feedbacks and an eventual runaway warming event which will be catastrophic.

You seem to be making a habit of mis-stating the view you're arguing against in order to make it easier to argue against. In this case, you're conflating the measurements and inferences from that (that temperature over the past century and a half has risen unprecedentedly steeply, and the inference that mankind was at least in part causal in that temperature rise) with the mechanism - CO2/CH4 as greenhouse gases, mankind's massive energy output, pollution.

Even the infamous Phil Jones had to admit that the biggest factor convincing him of an anthropogenic cause was...

"had to admit".. Your showing your prejudice, here. In the absence of anything else to explain the warming that has been measured, what would *you* say has caused it?

It's kind of how science works, though - in this case, looking at an effect and see if you can work out what has caused it. In the absence of a huge increase in energy input, or anything global, you look at what else has changed and see if there's a chance that one effect has caused the other - hence the focus on mankind's output of greenhouse gases as something that has changed markedly over the past century, and can be shown experimentally (if somewhat simplistically) to cause warming.

To make a point, a 1-2% reduction in cloud cover over the past 30 years could be enough to cause the observed warming. Such a decrease has indeed been observed, in spite of the proposed positive feedback between clouds and climate(4).

OK, I'll bite... You claim a "a 1-2% reduction in cloud cover over the past 30 years could be enough to cause the observed warming" unsourced, but link to an article which shows that there has been a reduction in cloud cover in China.. Regarding your first assertion, if you look a bit deeper rather than accepting at face value what you read on wattsupwiththat.com, you'll find it's a lot more complicated than that (http://journals.ame

tsoc.org/doi/abs/10.

1175/1520-0469%28197

2%29029%3C1413%3ACAA

GCF%3E2.0.CO%3B2); regarding changes in cloud cover, you'll also find that it's a lot more complicated than that, too (http://journals.ame

tsoc.org/doi/pdf/10.

1175/JCLI4031.1).

In other words, it's overly simplistic to say a 1-2% reduction in cloud cover could cause the observed warming; and globally that reduction of cloud cover hasn't happened so the point is moot. In that second article it does show large regional differences, so looking at a single area (even one as big as China) is not significant.

I agree that the models we have are the "best approximations we have at the moment". However, your attempt to extend this to an argument that they cannot, therefore, be incorrect is illogical.

It would have been illogical if that is what I had said. You've mis-stated my position - this is getting to be a bit of a recurring theme, isn't it?

N.B. I don't consider your comments or questions regarding evolution relevant or honest so I've purposefully ignored them. An attempt to align me with creationists only weakens your argument.

Dishonest? That's fairly rich coming from someone whose main arguments are nearly all against something nobody else is saying. Maybe, instead of getting all huffy and indignant, you ought to look to your debating style and not behave in a way which makes such comparisons appropriate.

Haha, your question was "over a period of 100 years has temperature *ever* risen that much before?" and I answered it. You can't get all grumpy because you didn't phrase your question properly! =)
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Since the instrumental record only goes back as far as 1850, we can only go off of proxy data which isn't as accurate. The natural variation of the climate regularly achieves 0.7 degrees over a century, but, since you want an example, the Younger Dryas apparently saw temperatures increase by over 10 degrees in a few decades.
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Your comment that the 1860-1960 overlaps more than half of the temperature rise of the 20th century raises an interesting question, though.
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Regarding the Medieval Warm Period (and even, other periods in the paleo record), I'm afraid you're wrong (1). I don't particularly want to go through every single dataset and paper for you because, well, that's for you to do. When you do, you'll find that the "hockey stick" is a very recent invention, the statistical methods of which have been discredited by McIntyre & McKitrick (2) as well as the statistician Edward Wegman in a report into the whole "hockey stick" debacle (3) which upheld the findings of (2) and found their findings "valid and compelling".
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You seem to be making a habit of mis-stating the view you're arguing against in order to make it easier to argue against. In this case, you're conflating the measurements and inferences from that (that temperature over the past century and a half has risen unprecedentedly steeply, and the inference that mankind was at least in part causal in that temperature rise) with the mechanism - CO2/CH4 as greenhouse gases, mankind's massive energy output, pollution.

I don't really know what you are trying to say here, it seems very confused. My point was that the enhancing of the greenhouse effect by additional CO2 and any moderate warming caused thereby wasn't under debate. I was merely clarifying my position.
.

looking at an effect and see if you can work out what has caused it

Again, you are getting confused between the observable warming that has occurred, the observable increase in CO2 that has occurred and the hypothetical high climate sensitivity (which has not been observed and could be much less than assumed) which will lead to disaster.
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With regard to the first paper you cited, if you actually read it you will see it is actually supporting what I was saying above. Effectively, clouds are complicated (I see you also agree with this), we know what their effects are when all other known factors are constant, but that isn't particularly realistic. The part of the closing conclusions which remarks...
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"The numerous, nonlinear and couple interrelationships between the factors that determine the climate suggest that in order to understand the possible role of cloudiness as a global climate feedback mechanism, it is necessary to have a realistic, large-scale, radiative and dynamical model of the land-ocean-atmospher
e system, that includes some microphysical aspects of cloud formation. Such a detailed model is clearly not presently at hand."
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....is still relevant today since little progress has been made in this area. Clouds are still simply parametrised values. Not dynamically modelled entities. Purely because the physics are poorly understood.
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The second paper is very interesting and I remember reading this some time ago. The limitations of the ground based observations don't help much with discerning higher clouds occurring above lower clouds and, more importantly, the effective cloud top height. This latter part is particularly important, as noted in the first paper you cited, as the height at which clouds occur (and their ensuing alterations as they progress) changes their climatological effect hugely (even the sign).
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As a side note, I've just noticed for the first time in Warren et al their finding that the -0.7% change over land is balanced by a +0.4% over sea directly contradicts recent, model-combined, studies which suggest that ocean warming should reduce low cloud over ocean and amplify ocean warming. It's also interesting to note that Warren et al find (as many have) that ENSO is a primary driver of cloud cover in a lot of their records.
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In other words, it's overly simplistic to say a 1-2% reduction in cloud cover could cause the observed warming; and globally that reduction of cloud cover hasn't happened so the point is moot.

That's quite a leap! You're springboarding off of a study from ground stations which, while admirable considering the data restrictions, has huge holes in coverage (look at the grid box coverage plots fig.5,8,9 etc.) and claiming that we have total, global coverage data.
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Considering the relatively tiny scale in change required (1-2%) in global cloud cover, along side the large percentage of the globe which is not covered (particularly over oceans), I hardly thing one can claim that "it hasn't happened". That's more than a stretch.
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It would have been illogical if that is what I had said. You've mis-stated my position - this is getting to be a bit of a recurring theme, isn't it?

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Okay, I apologise, I have misunderstood what it was you were getting at. What was your intended point when you stated:
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"...the models being used are the best approximations we have at the moment. Come up with a better explanation for that "modest" 0.7 degree rise and it will in time become the scientific consensus."
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Finally, I think you have understood my point regarding your attempts to malign me and the negative reflections they have on your own argument. I'll consider that particular matter closed.
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(1) http://www.ncdc.noaa
.gov/paleo/globalwar
ming/paleobefore.htm
l
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(2) http://climateaudit.
files.wordpress.com/
2005/09/mcintyre.mck
itrick.2003.pdf
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(3)
http://www.uoguelph.
ca/~rmckitri/researc
h/WegmanReport.pdf