There is even more to measuring warming than you indicate, and others can point that out. But please get the language right. 'Climate change denialists' is sloppy and misleading language. It is characteristic of climates that they change. No one known to me denies this. The debate is about whether warming has taken place, how much of it there has been, to what extent humans have caused it, and whether or not, if it has occurred, it is dangerous.

No one known to me denies warming has taken place - except perhaps Dr Tim Ball or Dr Bob Carter.

I would agree however, the 'debate' is about how much of it there has been and to what extent humans have caused it. Indeed, this so called 'debate' (in scientific circles) is usually couched in terms of studies in climate sensitivity and attribution. It is very robust.

Whether or not it is dangerous is the reason for the bun-fights between politicians - less so the scientists.

As to the term "Climate change denialists" - perhaps Stephen Kleim is just alluding to those who deny that climate change is, or can be, caused by human activity - and there are quite a few who believe that.

Oh dear! I said that no one known to me denies that climate changes! Yes, no doubt he did mean what you say he meant, but it is sloppy language. Why doesn't he say that some people are sceptical that humans have had much effect on whatever warming has occurred in the last fifty years? If that's what he means. That at least would be clear.

I am agnostic, rather than sceptical, and I have looked hard at the issue over the last three years. I don't think that the underlying measurements are robust at all. They are based on the daily average of the lowest maximum and the highest minimum for the points of record, averaged on a 100 sq km plot, averaged for the planet, and estimated where there are no recording instrument. Why do you think it is robust, let alone valid or reliable? It may be what we have, but it's not robust.

Stephen Keim writes:

“The earth stations which measure temperature do not cover every centimetre of the planet. Hadley leaves such unrepresented areas out of their averaging process. If, for example, the Arctic, which is poorly represented for measuring stations, is warming more quickly than other areas, the Hadley analysis would understate the process of warming.”
“GISS uses a technique (which they have tested for accuracy) which allocates to unmeasured areas the reading of their neighbours. Hence, a different averaging and a different set of results ensue.”

To my untutored eye this seems all very arbitrary. One can easily think of other exclusions.

• For instance all weather stations located above an altitude of 500m.

• All stations where local topography has changed over the years, since local structures may have an “urban heat island effect.”

• All data bases where the number of independent weather stations has been reduced by X% over last fifty years.

Indeed there is no end to the exclusion process.

The weather people should include in their reports an account of all likely errors and assumptions. Further an easily assessable description of their statistical methods and sampling procedures would not be amiss.

The term 'denialist' is used to suggest there's something immoral and an absence of integrity about those dissident voices among scientists who question the orthodoxy of Official Science, and it is used to intimidate others: dare to question the orthodoxy (that human activity is the principal driver of climate warming/change) and you are no better than a denialist. The term has clear meaning in terms of its most common intellectual use in relation to Holocaust denial. It has distant origins in its use by the Inquisition, in similar ways for similar ends.

What is needed is freedom of science in which dissident voices and rigorous debate are encouraged rather than the vilification of dissident scientists as denialists.

qanda: evidence for Bob Carter denying that climate has warmed? My reading suggests that the dissident scientists accept the IPCC estimate of an increase in global temperature over the past 140 years of 0.7 degrees.

The current reviews of procedure on the part of the IPCC and also East Anglia University, arising from Climategate and Glaciergate, will be worthwhile if they result in a return to the principle of open and free scientific inquiry.

The climate scientists all believe we should not be trying to understand their science, and just take their word for things.

They all say different things, they disagree and contradict, when you read what they say on their websites, you are left feeling they are a little oversensitive to questioning or criticism but are not backward in flaming or attacking competitors (and skeptics).

Not a conspiracy, just a common area of interest. If you're a scientist and don't go with the man made contributions to warming theory, well don't expect a grant any time soon, you denying bastard!

The money is for climate research to support Agw or other science areas, the effects of climate on your pet subject, like "Lions in the Serengeti and the effects of climate change on xxxxx" (insert unknown here, try to be original)

If you're a scientist and go along with the Agw theory, you're mainstream, one of the lads and in the team, have a grant, off you go, fine fellow that.

Gosh, is there any incentive there? You don't need a conspiracy, just a mortgage and the usual human nature attraction to conform.

Is it warmer now than ever before, some scientists say yes some say no - both passionately.

Have scientists ever been wrong? Have scientists ever fabricated results, tweaked them a little to get a good result?

Can anyone predict the weather, no, but if their models and science is so good - why can't they?

Because it's complicated.

Yes, we know it's complicated, but why do scientists make absurd statements about climate like, "it's simple physics", well if it's so simple, why can't you predict weather.

Many will pour scorn on this, as weather is considered too complex and too many variables to predict, but climate is simpler for some reason. What?

The community at large hear this strange and alarming contradiction, and put it down to "they just don't have a clue, and attack anyone who questions them" (no reason to deny anything, the scientists supply the fuel for skepticism)

That much, we do know

Amicus, genuine scepticism allows for the possibility that global warming is primarily caused by human activity. Most 'deniers' (sceptics) - from my reading - question the extent to which human activity contributes and others dare to question whether warming will be catastrophic (given observed trends and theoretical understanding as against sanctification of computer modelling) - maybe a continued warming will just be problematic, or maybe no big problem, or maybe advantageous on balance.

Science just does not survive without genuinely free and open debate. Charges of denialism seek to stifle that.

Regardless of that, however, there is good reason to support vastly greater investment into energy sources other than fossil fuels, as these will become depleted and more expensive due to massively increased demand upon them from places like China and India. Medieval windmills aren't the answer and solar cannot generate base-load power. This leaves nuclear and geo-thermal - but why not think big? Why so little support for fusion power?! (Answer: in my view, because capitalism stifles innovation because new capital will undermine existing capital)

The author says the two main sources for temperature readings but he forgets all about satellite measurements.. there are two sources of satellite measurements of temperature of the atmosphere (as opposed to the ground networks), UAH and RSS. Both of those show the peak at 1998. Hanson's GISS site needs to reword its calculations. But so many questions have been raised the ground network (all the sites using ground instruments draw considerably from the same network) that we have to default to satellite in any case. Climategate was only a small part of it.. there were also the problems raised over Steve Jones' allowances for heat island effect, and the very recent fuss over the measuring stations being left out of the network they all use.
Sorry fellas, but we have to use the satellites.
Now those measurements show an increase of about 0.6 degree C since the mid-70s and there is no real question that this decade is hotter than any of the preceeding decade for perhaps centuries.
1. Is that an unusual increase?
2. Is the hot decade significant?
Answers - 1. No-one knows. 2. No.
Even with the imperfect surface network we are seeing the present temperature record in high resolution, but what we know of past changes for which there is only low resolution (quality, accuracy, completeness) data there is nothing unusual about the increase.
We know climate goes through cycles, and we are in a high part of one cycle. There have been suggestions that industrial gases have boosted temperatures but the trouble with that is there is no real way to tell whether any part of the increase is artifical. Even if this proposition is found to be true making forecasts using that knowledge given the vast unknowns in atmospheric feedback systems is a waste of time.
As is now acknolwedged the great oceanic climate cycles are a major marker of climate and both the Pacifc Decadal Ascillation and the Atlanic cycle have turned into cool mode. Ergo temperatures will turn down..

byork, I'm open to climate change being added to by human activity, like land clearing, river course changes, farming practices and so many other possible sources of contribution, in fact I am pretty well sure those behaviors affect the climate.

What I'm not a believer in is that CO2 is THE culprit, there is no proof of that outside of climate scientists saying, well we know it can't be all these other factors, so it must be .. oh, that!

We don't know enough about climate to say that, which is why I'm skeptical, because if it was all so clear, why do climate scientists need to groom data?

Don't mistake skepticism of CO2 adding to climate change, to climate change skepticism - I'm not skeptical about, nor do I deny the climate changes.

I just got an email from an employer organisation in Victoria, one of the courses they offer is "How to recognize Carbon in the office environment and how to eliminate it", just the most absurd rubbish you could expect to hear. Is that what the "science" is about? We should be opposing that sort of crap, and the climate scientists do not.

I'm happy for open debate, are the Agw believers?

It seems the suppression of debate and insults (Denier!)come from the AGW side, would you agree?

So let's have a debate, but how do have it not reduced to slanging and insult? We haven't been able to so far have we?

Why do climate scientists want debate now, they never did before, it was all consensus, and the debate is over?

Whenever they are put to the test, they humbly request open debate .. yeah, right, sure they do.

Someone mentioned fusion on another article today and was attacked by a climate scientist, well they claim to be a scientist anyway, who knows this is an opinion site.

Me, I'd like more investment in bio fuels, like grassoline .. let's mow! Seriously, renewables that we can grow, have got to be considered, currently we seem to be pursuing renewables where we can't control the source.

Take a legal matter to your lawyer, & you'll get an opinion. Take the same matter to 5 more, & you'll get five more, & different opinions. And this is in their area of expertise. They can never agree.

In that case, why would we pay any attention to the opinion of these blokes, when it comes to something they know nothing about?

One thing this AGW debate has brought home to me is just how lacking in any ability to understand anything are the legal profession, & even more suprisingly, the economists.

With the economists you would expect at least some understanding of numbers, but no, they have almost the least understanding when you talk figures.

Only the social science people, who could not possibly make the suggestions they do, if they had not stopped studding any math, after year 10, show less understanding.

I suppose one should have expected the lack of ability with numbers with economists, in view of the global financial crisis they have inflected on us, but it does still come as a bit of a surprise that they are quite as bad as they are.

The leagal blokes obviously just don't care. They'll take "evidence" from anywhere they can get an opinion that suits their case.

So much talk and dogma about what the temperatures were in the last 10 years. What is always totally ignored by the believers in the gw religion is the fact that past prophecies of global cooling and warming often have be proven totally false despite the 'science' or should I say dogma being settled. Whether it be the recent freeze in Europe and America or the flooding of Queensland anyone with half a brain can see that these prophets really are guessing. If you want to call it science so be it but to slam and label people for questioning the dogmas is sheer arrogance.

Amicus, yes, I agree that "the suppression of debate and insults (Denier!)come from the AGW side".

It does worry me, though, when the other side shows a similar tendency at times. The "suppression of debate", however, can only come from those with the power to suppress debate - and that's not the skeptics!

Amicus. Many of the same inconsistencies and arbitrary decisions apply to short and medium term weather forecasting as are used in long term climate predictions. E.G. There are several different definitions of "average temperature". Some are good for certain purposes (crop growth, weekly forecasts, evaporation predictions, etc), others for other purposes. Those in the trade know the subtleties and why, outsiders who ignore the complexities (the ignorant) may see it as arbitrary, however it is just the nature of the beast.
Clearly, the weather report is less than "perfect" in the sense that a layman can easily digest it, yet no one sane would claim that because of this it is useless.
One of the major reasons that shipping and aircraft are so safe these days is because they *can* rely to some extent on forecasts and predictions made by models, despite the so called flaws. Chaos dictates that specifics will always be limited, yet the shape of the attractor, the range of possibilities certainly can be modelled and predicted.

...As for the CO2 issue: Yes, it is settled. Solid theories predict certain patterns: If it were sunshine variation the numbers would go one way. They haven't. The fact is that all viable alternate theories to CO2 induced warming have been considered, tested, and discarded because the predictions that have been made by the CO2 model, even the more incredible and formally dismissed (science is inherently conservative and sceptical), are now tracking with the real-world data.
Sure there is ongoing debate about details, but there is enough agreement on enough things to say the big debate is over...Warming will occur, it is due to CO2, it will cause change that is so rapid that plants and animals will not be able to cope, and for the human animal it will cause untold suffering and probably cause wars. If you want an exact date on when the ice fields will collapse you will get much "debate"; just how high the seas will be by 2050: very debatable.
You are aware of the butterfly effect? Well in the terms of chaos theory we know the attractor is shifting radically, yet we cannot, as always predict the trajectory along the attractor nor when some of the tipping points will "tip". That they will tip however is as certain as certainty can get.

Byork, it constantly amazes me that with all the financial backing and all the sympathetic media resources at their disposal, the Agw brigade constantly complain about how they are getting beaten up.

You can count the public skeptics of Agw and the skeptical media in Australia and still have fingers left over, yet they act as if there is some huge conspiracy against them.

There isn't, it's just their case is so weak it invites skepticism .. you would expect with all the resources and power they could suppress debate, as they thought had been done pre-Copenhagen.

Why do many scientists doubt and are skeptical as well?

You have to ask, is there another way to explain the additional, if it exists, warming - as curmudgeon says, it may be cycles we do not understand - that also sounds reasonable.

If they really are as wrong as many think, and the climate goes into a cooling phase, against all the predictions of doom - there will be a lot of egg on face and the remains of climate science credibility (such as it is now) may never recover.

It will be the byline of jokes and the definition of hubris forever.

qanda,

I have urgent need for credibility assessment of Ferenc MISKOLCZI Hungarian physicist's allegedly constant, law.

I don't understand the maths but it seems to me that conservation of energy and matter is being bent a bit. Can you ask around and get back to me.
Thanks
examinator

Gee, Ozandy, I wish I was as certain about what's for dinner tonight as you are about the inevitability and the effects of global warming. By my calculations five propositions need to be true for the AGW alarmists to be correct: here they are and here are some extremely generous evaluations of their probability.

1. CO2 levels are rising -- probable but not undisputed (see http://tinyurl.com/yl789dc for instance) -- probability of, say, 90%.

2. This rise will cause major climatic changes -- certainly not proven, but let's be generous and allocate a probability of 75%.

3. The negative effect of these changes will outweigh the positive effects -- AGW enthusiasts don't say much about this but if I was in Russia or Canada I would be looking forward to a warmer climate. We know already that more people die of cold than heat, and that many people deliberately emigrate to warmer climates -- let's say 70% for this one.

4. We can stop these changes through human effort, given the current state of the world. Copenhagen -- need I say more? 65% for this.

5. The costs of stopping the changes will be less than the costs of allowing them. Also very dubious -- let's say 60% for this.

Multiply this out and what do we get? An 18% chance that all five of these are true. And on that 18% chance we are meant to bet our economy and our children's prosperity? Come now!

The White Queen told Alice that she could believe six impossible things before breakfast. AGW alarmists are only one short.

Steven Keim is a lawyer and I have the greatest difficulty beliveing he has any sincerity, only the attraction to the cause of making the law complicated, unjust and very profitable.
That said he would have seen many many hoaxers in his time, all with very good stories and all the evidence to back it up. y2000 Bug, Ozone holes and now a tax on the air we breathe. That is just brilliant all us muppets have to pay it excepting of course the very rich and others who have "Charitable" (Tax free) status.
Steven just does not get it! Say reduce pollution, reduce waste and we would all be right behind you. Say we will increase the tax take and public service pensions and we all know we are being well and truly duded! Understand now?

Stephen Kiem, a well-known AGW proponent has quoted two of the most disreputable sources he could possibly find. The Hadley (Climategate!) Research Unit for goodness sakes!.

Being an ideologue does not eliminate the need for research and checking facts.

Here is a section of the interview by the BBC with Phil Jones (University of East Anglia, Hadley Research Centre)regarding this very question (after he was caught out):

B - Do you agree that from 1995 to the present there has been no statistically-significant global warming?

Yes, but only just. I also calculated the trend for the period 1995 to 2009. This trend (0.12C per decade) is positive, but not significant at the 95% significance level. The positive trend is quite close to the significance level. Achieving statistical significance in scientific terms is much more likely for longer periods, and much less likely for shorter periods.

(A weak way of admitting he was dead wrong. I'm only "just" wrong!!)
http://news.bbc.co.uk/2/hi/science/nature/8511670.stm.