This from gavin at RealClimate in 2004 is interesting. This is the last paragraph:

So what does this all of this imply? First, short term observations should be interpreted with caution: we need more data from the Antarctic, over longer time periods, to say with certainly what the long term trend is. Second, regional change is not the same as global mean change. Third, there are very reasonable explanations for the recent observed cooling, that have been recognized for some time from model simulations. However, the models also suggest that, as we go forward in time, the relative importance of increasing radiative effects, compared with atmosphere and ocean dynamic effects, is likely to increase. In short, we fully expect Antarctica to warm up in the future.

I’ve highlighted the bit that seems to be directly contra to what you said.

On ice loss, have a look at this from Jan 2008:

The team found that the net loss of ice mass from Antarctica increased from 112 (plus or minus 91) gigatonnes a year in 1996 to 196 (plus or minus 92) gigatonnes a year in 2006. A gigatonne is one billion metric tons, or more than 2.2 trillion pounds. These new results are about 20 percent higher over a comparable time frame than those of a NASA study of Antarctic mass balance last March that used data from the NASA/German Aerospace Center Gravity Recovery and Climate Experiment. This is within the margin of error for both techniques, each of which has its strengths and limitations.

In other words there’s nothing going on down there that would disturb the AGW paradigm, but in terms of sea level change…

However, there is no question that warming happened in the last couple of decades of 20thC, what is being debated is why.

Have a look at what gavin says about the attribution of 20th Century climate change to CO2. If you want to argue with him you need to get your head right into the science of the physics and chemistry of the topic, the way observations are made and conclusions drawn, and then get your head into climate model construction, then come up with something that can be peer reviewed and published.

But one of the reasons why I feel reasonably comfortable with the AGW story is that at the end of all that it has coherence and tells a consistent story that explains the main features of what has happened in the last 65 million years and is understandable by the interested lay person.

Re confirmation bias - sure. I agree, and I guess that may be one reason I seized on 1938/34.

However, there is no question that warming happened in the last couple of decades of 20thC, what is being debated is why. Given the implications of the costs and the changes/damage that can be done to civilisation via inappropriate policy, whatever assumptions lie behind it, it is essential that the assumptions be sound and justified. To me, when Freeman Dyson discounts the role of CO2 in global warming, an Al Gore slide show doesn’t cut the mustard. And yes, I know mentioning Dyson seems an appeal to authority, but it isn’t. It is more a matter of when someone like that expresses an opinion, a wise man considers it. Or maybe that’s just confirmation bias again.

bespeaks a mindset that is scrambling to find anti-AGW evidence. At least that’s the way I see it.

And I, on the other hand, see so much reason to question the AGW hypothesis, that I ofttimes find it incomprehensible that others don’t.

Oh well, funny old world, innit?

My perception is that your position is to pick holes in the AGW position, which has it’s uses if backed by sound science.

I saw the 1938 thing as so far off reality that it indicated an extreme cherry picker. Frankly the notion that “the 1930’s figure nonetheless demonstrate that there is nothing special about current temperature levels” still bespeaks a mindset that is scrambling to find anti-AGW evidence. At least that’s the way I see it.

But I’m willing to accept that you are writing in good faith. I actually have to go out and work now and may get back to a more detailed response this evening, but I’m severely time-poor at present.

Re. 1938, you are right, It was a few months since I last read on that, and I had remembered it as global, not just the US. I stand corrected, and thank you. However, this matter is about temperature trend, the 1930’s figure nonetheless demonstrate that there is nothing special about current temperature levels. They are not out of court in historical terms. If you can demonstrate otherwise, I am happy to listen.

As far as Antarctica does, I am not obsessing, merely raising the matter that the Antarctic climate trends, along with a number of other observations – see the list, serve to invalidate the AGW hypothesis.

Regarding your statement on Antarctic ice loss, you will find here a 2002 NASA report on the increase in Antarctic ice cover, 1973 - 1999, and here, a report of the record cover of ice 2007-2008. As you see, ice was lost on the West Antarctic Peninsula as we previously discussed, but continental Antarctica is gaining ice, year on year, with no significant sign of ice loss or temperature increase. I am aware of SBS news, and other organs, reporting on the break of a, huge by human standards, miniscule by any comparison of what is there, portion of the Wilkens ice sheet on the West Antarctic Peninsula a couple of months ago. I am aware that the WA Peninsula is warming, but that is a miniscule effect compared to the main continent. Nearly 200 square miles of ice broke of the Wilkens sheet, in two chunks, but the continental edge as a whole, as at the beginning of April, had a level of sea ice cover roughly one million square miles greater than at the same time last year. The extra growth in seasonal sea ice cover over the previous year, in just this years cooling season to April, months before peak cover, was five thousand times greater than that lost from Wilkins. Puts the reliability of journalistic reports into perspective, doesn’t it?

As far as boundary effects go, if 2007 Arctic ice cover is being used as an example of AGW in action and validating the models, as it is, then intellectual honesty requires the AGW proponents to acknowledge that Antarctica invalidates the models.

Your criticism that I haven’t changed my mind is unreasonable. As demonstrated over the 1938 temperature issue, I am willing to change my mind if my information can be demonstrated to be incorrect, but right now? I have been given no reason to do so.

The objective facts are - the warmest year in the last one hundred years was 1938, temperatures spiked in 1998, fell back and then continued their warming trend until 2002, at which time, with minor wiggles, they flat lined.

I don’t know how you could get 1938 as the warmest out of this graph from Wikipedia or this one from NASA GISS. They can’t be that far out.

It is true that there was a silly kerfuffle last year when 1934 was found to be numerically slightly warmer than 1998 in the US of A, which from memory is about 2% of the planet’s surface, when NASA corrected some data.

I say numerically because the change was from a position where the two values were statistically indistinguishable to the position where the two values were statistically indistinguishable. In other words nothing changed.

I don’t know why you are obsessing about Antarctica. I’m not an expert on models, but I understand that some of them have problems with the polar regions. I think it’s got to do with numbers as you approach a point. But if you look at
this image which comes from NASA GISS via this page and represents the changes from 1880-2006 you’ll see where the action is. Nevertheless Antarctica is still losing ice, and in increasing quantities, and when big slabs fall off they end up in the sea.

After your comment at 29 I decided that discussion with you wasn’t going to change your mind, so that’s it from me. Tim Lambert might engage. It’s up to him.

I had a look at your site, but all I could see was you making assertions to counter someone else’s assertions. However, I accept you write in good faith, and accept that you could provide references for your claims. That being the case, I accept and acknowledge your point.

However, there has been no dispute of the central issue, and that is that the AGW hypothesis, as presented by the IPCC and tested by the forecasts of the models it cites, has been falsified.

The models still fail to anticipate the temperature flatline since 2002,

The models require continental Antarctica to warm, but it has cooled and the sea ice, both this year and last, is at record extent.

The models specify that the Earths surface will warm as a result of the troposphere warming, and the heat being radiated back. The troposphere demonstrates no such level of warming. The temperature increase we have seen up to 2002, therefore, according to the models, cannot be as a result of CO2 forced greenhouse effect.

CO2, even according to AGW hypotheses, is incapable by itself of causing significant temperature increases. The hypotheses requires that atmospheric temperatures, slightly increased by increased CO2 levels, will result in greater moisture takeup, resulting in greater cloud cover; increasing insulation, cutting heat radiation and forcing temperatures higher – resulting in further increased moisture levels, a classic positive feedback effect. This is the assumption all the models make in their forecasts. In fact, increased temperatures are causing a negative feedback, reducing cloud cover and mitigating the temperature increase.

The models forecast that the oceans temperature will rise, alongside atmospheric and surface temperatures. They aren’t. In fact, the oceans could be cooling.

That is five separate examples of the IPCC AGW hypothesis being falsified. As I stated earlier, there may be valid explanations within the AGW paradigm, but none have been presented. Under the circumstances, it is still possible to ‘believe’ in AGW, but it must be a matter of faith, not science. Faith being belief in the absence of evidence.

I have presented five, but why five when, to paraphrase Einstein, one would have done? Well, no matter which example is used, someone always comes back with a dismissive, “the science is settled” attempt to brush it aside. That approach is easier with one than it is with five.

I look forward to reading refutations of each of these.

Nevertheless I googled to find the article, which it seems appeared in the Australian of 26 April. It seems to be based on some stuff written by Chapman, which has been roundly debunked in various places, notably by by Deltoid and again David Karoly via Deltoid.. This is a quote from Chapman:

“The next descent into an ice age is inevitable but may not happen for another 1000 years. On the other hand, it must be noted that the cooling in 2007 was even faster than in typical glacial transitions. If it continued for 20 years, the temperature would be 14C cooler in 2027. …

Well, yes, but 2007 is an anomaly with a ready explanation and it’s always unlikely that a 12 month “trend” in the weather will continue for 20 years. In fact I’d be astonished if you could find one instance in the record.

Marohasy picked it up as you’d expect. On her blog there are commenters like Luke and Ender who are quite knowledgeable about climate change who regularly comment on rubbish science. This time they thought it was too stupid to bother.

Chapman, Pearson et al are mightily impressed by the 50 million year slide in the temperature and rightly so. But Hansen et al have painstakingly sorted out what was going on, and the main story happens to be CO2. I’ll come back to this in a later post.

Anyway Sir David Attenborough has spoken on AGW. So that’s it then. No more argument!

The problem is, the IPCC was not set up to determine whether GW was A, but rather was instructed to assume that the case was true. It effectively has no mandate to question the assumption, thus the content of the reports it puts out. My understanding is its mandate is to demonstrate the A, not question it, and to propose policies to mitigate its effects, whether it exists or not.

This seems to be the latest talking point for the denialists. Not only is not true, you can find that it is not true in about two minutes.

There is a decent overview by Stephen Schneider of Stanford on Ockham’s Razor this week

You mean the ex global warming denier and blabberer of this nice quote?

We have to offer up scary scenarios, make simplified, dramatic statements, and make little mention of any doubts we might have.

But since everyone else on this thread has lost interest in the guilt of said Duffy, perhaps Paul should just move on to his next indictment.

There is a decent overview by Stephen Schneider of Stanford on Ockham’s Razor this week.

How well does the film handle the science? Admirably, I thought. It is remarkably up to date, with reference to some of the very latest research…

There are a few scientific errors that are important in the film…

Perhaps a Distinction rather than a High Distinction.

We’ll leave Antarctica for another day, but if you look at the global anomalies they are much stronger around the North pole at this stage.

Currently Michael Duffy presents the program Counterpoint along with Paul Comrie Thompson on ABC Radio National. They like to present non-mainstream points of view, but they have taken a definite anti-AGW stance. Last year they had a silly “carbon train” theme with a cow mooing, meant to represent a gravy train and a sacred cow. They believe in the great conspiracy where AGW scientists everywhere are maintaining their funding by knowingly publishing false science. It’s too silly for words to describe.

It’s not all he does, so google if you’re curious.

Your mate Bob Carter never responded to this dissection of his Melbourne rotary address to my knowledge, because you couldn’t. It demonstrates how wrong he is about the basic science. He’s also been taken apart several times at Deltoid.

Recently in a talk he had polar bears existing several hundreds of thousands of years before they evolved from the brown bear. His mental set is such that he is quite unreliable in presenting information. His howlers are such that you just can’t trust him as a source.

I’m not a scientist, but I get the impression that his own work is quite specialised and that his excursion into climate science generally is outside the scope of his genuine expertise.

Anyway Paul has a pretty good handle on him, and Paul’s knowledge is definitely to be respected.

Paul, your evidence establishs that Michael Duffy denied AGW years ago, but not that he denied GW. It is the latter that he stands accused of.

Case Dismissed.

My evidence establishes beyond doubt that Michael Duffy generally endorsed the views of scientists who denied GW, and that he did not publicly qualify his endorsement of their views to the extent of stating any disagreement with their statement that:

over the past two decades [to 1998], when CO2 levels have been at their highest, global average temperatures have actually cooled slightly.

which was a key element of the evidentiary basis for their petition which he was explicitly endorsing.

The case against Duffy is still very much alive unless he or his lawyer, Bill the Troll, can come up with an alibi.

Of greater significance in the wider scheme of things is that in 1998 the world’s largest organised group of denialists was promoting the hypothesis of [drum roll] Global Cooling!

Now Duffy, Bill the Troll, Andrew Bolt, Bob Carter, etc., have, in their several ways, implicitly admitted that the world’s largest organised group of denialists was wrong about global cooling the first time they tried it on, and the Oregon crowd themselves quietly shuffled away from this trope to their next talking point du jour.

Now, ten years on, the Stupid Cult of Cooling resurfaces.

2 Peter 2:22 says it all, really:

But it is happened unto them according to the true proverb, “The dog is turned to his own vomit again”; and the sow that was washed to her wallowing in the mire.

Clearly Stalin’s table manners are far worse.

(I suppose it is what you expect of Russians).