Wrong again, times two

Watts Up With That from 24 March ran at the top of its blog for a good few days the story of the excruciatingly tedious Steve McIntyre finding that there was “deleted data” at the starting end (so to speak) of a graph of tree ring proxy data by Briffa that appeared in Science in 1999. “Where are the academic cops?” asked Watts in a facetious post heading.

Of course, this then got picked up by Andrew Bolt on 25 March, and Catallaxy, the blog where the centre right and libertarians go to be wrong about climate change, on 28 March. The only surprise in this process is that Tony Abbott didn’t turn up in Parliament flourishing a copy of the graph.

Someone at Watts (after scores of comments claiming this was another outrageous outrage) did suggest that, well, maybe excluding the data that is so obviously not a reliable proxy in the period in question is the right way to go if, you know, you are trying to work out the correct temperature in the period.

Turns out the explanation is even better. Nick Stokes explains:

A file had been discovered which showed data down to 1400, and if you plot it, it goes into oscillations in the years before 1550. Since it is clear that this is in a period of rapidly diminishing data, and very likely caused by that, I thought that would die fairly quickly, but no, as these things go, it was promoted to a grand ethical violation, megaphoned at WUWT, and taken up at the Air Vent, where it was seen as "unbelievable fraud"….

Well, it seemed clear to me that the available data is just getting low as we go back beyond 1550, and the wild swings are just the result of the growing noise, as you'd expect. And I haven't found anyone who seems to seriously think they reflect any kind of reality. So Briffa sensibly stopped at 1550 to avoid misleading the public….

[Referring to graphs of the number of sites plotted to produce the data]: As you can see, the number of sites is dropping rapidly before 1600, and is down to about 40 near 1550. Here is the expanded region between 1400 and 1600

As you can see, the rate of decrease is quite sharp near 1550. There's no absolute rule on where you have to say that a plot has to be stopped. The noise rises relative to the signal in a continuous way, and I don't curently know how to quantify whether 40 sites is likely to be sufficient. But neither do the critics. What is clear is that the observed rapid changes observed in McIntyre's graph are closely associated with the steep reduction in data. In those circumstances, I would be very uncomfortable about presenting them as real. And I don't think referees would let me.

Nick goes on in the next post to show why having fewer sites can easily lead to spurious oscillations.

So, as expected, there is an explanation, and it is not sinister, especially in the context of a Science piece which was also (apparently) only a short commentary.

Will the readers of Andrew Bolt ever know that? Will Andrew ever have read this explanation.

Would Sinclair Davidson ever offer an explanation post at Catallaxy? Does he ever offer anything other than skeptic stories recycled from skeptic sites?

The other “Watts is wrong” story making the news is the “hero to zero” path that Berkley physicist Richard Muller has made in the space of a few months.

Once again, Sinclair Davidson gave this story recent prominence at Catallaxy by posting a Youtube of Muller’s lecture about “hide the decline”. Muller’s take on this always appeared to me to show self-aggrandisement about how it wouldn’t be done like that at Berkley, and he had been criticised at ">Skeptical Science for muddling the details.

But his other claim to fame was to be on the BEST project to independently compile a temperature record set.

As everyone knows by now, Muller has told Congress that the early results show close uniformity with the existing temperature sets: you know, the ones that Anthony Watts has spent years trying to show were defective and misleading.

The Economist has the story, told in relatively dispassionate terms, and many on the “AGW is real” side of the fence are now enjoying enormously the swing against Muller from the climate skeptics side. Of particular amusement is the vehemence with which the professional disinformation site Climate Depot, of Marc Morano fame, has gone for his jugular. As the headlines will change, have a look at this screenshot (complete with Muller with a snake photo, presumably designed to make him look at tad nutty):

Of course, sites like Salon are enjoying the whole turnaround, as well they should.

I said before recently that the climate skeptics have been slowly moving away from their pet idea that temperature increases over the 20th century were all an illusion. This only confirms the move – from now on it’ll be nearly all “lukewarmenist” arguments: yes, the temperature has increased over the 20th century, but not quite as fast as climate science said, and look at the last [insert cherry picked period] has not got significantly hotter at all: it’s probably all stopped now and that just shows what idiots those scientists were! And besides, even when the graphs go up again, maybe it’s all a good thing. etc etc.

Update: I just typed a really long comment in response to the politely worded skepticism of sfw in comments, but Blogger did not want to accept it (Blogger seems to be having some widespread comment issues lately). I did not want to lose the work, so here goes:

Hey, it's nice to have someone on your side of the fence who is moderate in tone, and thanks for the comments on the blog.

I'm not sure if you've been reading me for long time, but I was initially a bit of a fence sitter on the AGW issue. But I decided that ocean acidification was a sufficient enough reason to push for less CO2 urgently anyway. It is a problem with no easy solution other than "stop putting so much CO2 in the air", and initial studies nearly all showed serious problems with the sea critters they were testing.

Over the years, I think it fair to say that the fact of the ocean pH drop at the predicted rate has been confirmed by measurements, but the results of lab tests have become more ambiguous. My initial thoughts were that these tests would be straight forward in identifying which creatures would suffer first and and which wouldn't, but the process of doing this accurately was a lot more complicated than I initially credited. Also, a bit to my surprise, the detailed biochemistry of sea life seemed to have a lot more gaps in it than I would have expected. So, the type of test results that have been coming out in the last year or two have been harder to understand.

I still think it is a serious issue. I have particular concern about the future of pteropods, which appear to be a very important link in the food chain in polar waters. As for reefs, I still have an open mind as to how soon or how badly they will be effected. Some corals do worse than others in lab tests, and generally it seems to me they are hardier than expected, although combining acidification with much higher ocean temperatures just makes predicting their future very hard.

In any event, it now seems to me that the slow moving nature of the process makes it harder to convince people of the need for action on CO2.

At the same time, it seemed to me that the evidence for AGW and associated climate change was firmer than I had understood, and as I was never convinced of the issue by popularisers like Gore and Flannery (in fact, I have always been a tad suspicious of them), it mattered little to me that they had made mistakes in their presentations.

I also realised that the opposition to it is in fact ideologically driven. I genuinely find the climate science sites of Real Climate and Skeptical Science to be measured in tone and reasoned in exactly the way that the likes of WUWT are not. Skeptics just continually ascribe the worst motives to climate scientists, usually from a position of ignorance.

The popularisers of the skeptic side, with their grab bag of arguments, also made me realise there was no genuine attempt to be rationally critical of climate change science; the likes of Monckton and his ilk had clearly decided that it was all rubbish (often alluding to ludicrous conspiracies behind it) and anything would go in advocacy. Mistakes would be repeated and believed, all because it fitted into preconceived ideas in the audience.

Now, I do accept that there are actual scientists on the climate change side who have made careless overstatements, but usually on very particular things like glaciers, droughts, the future of snow etc.

And I can understand why people like you say that it looks like its unfalsifible.

Here's what I think: it's actually really complicated, and not easily communicated with simple messages. Messaging mistakes will happen, and will cynically be exploited by ideological skeptics, but that's no reason to throw out the baby with the bathwater.

It turns out, for example, that a significant number of papers had talked about more drought in the long term for Australia, but broken by more intense periods of rain. This is what we just saw happen. Yet it is so easy to point the finger at Flannery and say "hey, he said cities would be running out of water by now."

I figure: he's not even a climate scientist per se, and big deal, he made an exaggerated comment here and there. M'eh, if papers are there that did predict what would happen, big deal.

The same with heavy snow in the Northern Hemisphere this last couple of winters. Yes, it seems few scientists predicted it before it happened, but some in fact did. The mechanism seems credible (less ice over northern areas such as Hudson Bay), but won't be proven for some time yet. So, one guy said British kids wouldn't see snow again. He was wrong, he exaggerated. But he wasn't speaking for every scientist and simply should have been more cautious.

The Russian heatwave: a really severe event, which (I note) some NOAA scientists say wasn't really caused by AGW. I'm kind of expecting that they have in fact leapt too far to the cautious side on that one. In any event, it (together with the European heat wave of some years ago,) shows how serious (including for food supply) more regular severe heatwaves could be.

Climate change scientists are always going to be hobbled to a degree by the complexity of the climate system and the short term blips along the way to seeing the long term trend.

I think it is reasonable in such a system to make allowances for things that may yet happen to the weather that were not predicted in detail or more widely. (In fact, as I say, it can turn out they were predicted, but were just less emphasised in the public arena.)

But here's the key thing: the uncertainty in how exactly the climate change manifests locally (and, in a sense, globally) is no reason to dismiss the seriousness of AGW. The examples of the last couple of years of floods, heat waves and even blizzards have not been (more or less unexpectedly) good events: they have been (more or less unexpectedly) bad events, and there are mechanisms to explain them as a consequence of AGW.

So, while you see non falsifiability, I see danger, and all the more reason to take CO2 reduction seriously.

Quite a length for a comment, hey!