Yes indeed, time to weigh in on the great issue of the day: Mr Justice Burton vs Al Gore.
My first point was going to be, that it was a poor idea to have judges deciding science. Its still a point, but possibly not a major one in this case, because it looks like the amended guidance notes, which contain the core of what needs to be said to correct the film, were “agreed during the case” – exactly who agreed them is unclear, especially on the govt side, but at least it wasn’t just the judge.
[Update: IPCC and Gore get 2007 peace Nobel "for their efforts to build up and disseminate greater knowledge about man-made climate change, and to lay the foundations for the measures that are needed to counteract such change". IPCC, good. Gore... I'll reserve my opinion for now]
Wiki is shaping up for a fine edit war on this (though amuingly, the page prot state a bit earlier was only tangentially related); meanwhile Inel is in my opinion too kind to Gore/AIT. James is rather more acerbic and has the good taste to ref me. mt, with usual boldness, has set up a experimental wiki just for the Nine Points of Doom.
Before I go on, I’m going to give my opinion on what is the heart of the problem, and indeed with so much greenpeace-type stuff too: that the basic truth about GW is too boring to present to a mass audience and so people feel a need to sex it up. The bottom line, if you want to know whether its getting warmer, is to look at the temperature record. Which shows its getting warmer. There, are we done now? No of course not, too dull. So we need… The Snows of Kilimanjaro melting. Or charismatic megafauna drowning. Or whatever. Yes I know that a simple straightforward presentation of the IPCC SPM, which could be done in about the same time, would have audiences running away screaming. Its a problem.
But what would also be a problem would be if all the good guys felt obliged to get trapped into defending AIT to the death. I hope that doesn’t happen (Myles Allen on R4 last night didn’t). It should be clear that AIT is a partisan film, not a source for the science; for that we have the readily available IPCC (or wikipedia, if you want a readable summary). AIT is in some danger of becoming a cuckoo overshadowing what it is supposedly explaining. Skeptics can find it very convenient to attack the film, and thereby pretend they are attacking the basic science.
Realise that this judgment has been badly, consistently and lazily reported. The core of the judgment is I have no doubt that Dr Stott, the Defendant’s expert, is right when he says that: “Al Gore’s presentation of the causes and likely effects of climate change in the film was broadly accurate.” It goes on to discuss “errors” (note the quotes – back to that later) but the overall judgment is the above. Of course, thats not interesting enough, the angle has to be controversy, so even the grauniad has Gore’s climate film has scientific errors – judge and I’m sure elsewhere is worse.
Onto the “errors” question, which turns out to be pleasingly ambiguous. Para 17iii says “There are errors and omissions in the film”. But 18, this has become “some of the errors, or departures from the mainstream” and by para 23 this has become “‘errors’” (note internal ‘ quotes). It remains like this, except for a brief removal of the scare quotes in para 34. Which means that whenever Burton talks of the 9 errors, he writes “9 ‘errors’” – which is to say, he is not calling them errors, merely noting that others have called them errors. Assuming this is deliberate, then we are entitled to deduce from the judgment that he thinks there are at least 2 errors (from para 17) but not that he asserts that there are as many as 9.
The Nine ‘Errors’
Note: in most cases, Gore doesn’t actually *say* mistakes but *implies* them. Thus, on sea level rises, he does *not* (as I recall; happily the judgment includes transcripts) actually say “sea level will rise 20 feet within X years”, he merely talks about what might happen if sea level did rise by X. Technically, this saves him. Either the judge has missed this subtlety or (rather more likely) has decided that this is mere equivocation: Gore is clearly giving the impression that this is likely “soon”.
1. Although many of the examples in this scene are well chosen to illustrate the effects of human induced climate change, the causes of the recession of snows on Kilimanjaro are complex and related to local factors. It cannot be established that this is mainly attributable to human-induced climate change.
K seems to be a complex case; plough through the RC take if you like. I think the bottom line is that whether snowless K is from GW or not is unclear, but that its certainly not a good example to use for attribution. K isn’t good evidence *for* GW. But the retreat of glaciers worldwide is. So we’re back to sexing it up: Gore’s basic point is fine; the icon he uses isn’t. As the guidance notes says.
2. Pupils watching this segment might get the impression that the graph plotting CO2 against temperature over 650,000 years proves that recent rises in temperature are caused by CO2. The latter conclusion is accepted by the great majority of the worlds climate scientists, but cannot be proved by reference to this graph. Closer examination shows that, for most of the last 650,000 years, temperature increases precede CO2 increases by several hundred years. and then goes on to say that the relationship goes both ways.
Oh no, not this one again. As far as I know the best explanation of the CO2-T in the deep cores comes from Eric Wolff; there is a longer RC version. The bottom line: the skeptics are completely wrong to say explicitly (as they do) that the CO2-T lag *disproves* GW. Gore’s presentation is largely correct, and about as good as can be done within the space. The ice core record doesn’t *prove* GW but is entirely consistent with it.
I think the judge should probably have left this one alone. It will be a bloody good school class and teacher that manage to make sense of the notes.
3. There is insufficient evidence to establish clearly that particular one-off weather events, such as Hurricane Katrina, are attributable to climate change. However, the IPCC concludes that it is likely that there has been an increase in intense tropical cyclone activity in some regions and more likely than not that humans have contributed to this
I agree with all that.
4. It is generally Accepted that the evidence remains insufficient to establish a clear attribution for the drying out of Lake Chad
Dunno. Sounds fairly likely though.
[Update: G points me to "Biasutti, M. and Giannini, A. 2006: Robust Sahel drying in response to late 20th century forcings. Geophys. Res. Lett., 11, L11706. doi:10.1029/2006GL026067.", see-also here, so Gore may be somewhat or at least arguably right -W]
5. It is not clear which study Gore is referring to when he talks about Polar Bears drowning.
Bears again, argh. As far as I can tell they aren’t much use as an example yet, though they might be for the future.
[Update: In the comments, C argues that there is a perfectly good study supporting Gores position -W]
6. The IPCC assess that it is very unlikely that the ocean conveyor (also known as the meridional overturning circulation or thermohaline circulation) will undergo a large abrupt transition this century, although it is very likely to slow down. Most scientists would regard talk of an imminent ice-age as speculation.
Gore talks about this, again in a prediction-free way intended to imply trouble, but I forget his words (see para 27). The guidance is correct; Gore was probably misleading.
7. The IPCC reports predict that, if the temperature were to rise by 1-3C, there would be increased coral bleaching and widespread coral mortality unless corals could adapt or acclimatise, but while there is increasing evidence for climate change impacts on coral reefs the IPCC concluded that separating the impacts of climate change-related stresses from other stresses such as over-fishing and pollution was difficult.
Not my thing.
8. Pupils might get the impression that sea-level rises of up to 7m (caused by the complete melting of Greenland or half of Greenland and half of the West Antarctic shelf) could happen in the next decades. The IPCC predicts that it would take millennia for rises of that magnitude to occur. However, pupils should be aware that even smaller rises in sea level are predicted to have very serious effects. or Burton: “This is distinctly alarmist, and part of Mr Gore’s ‘wake-up call’… not in line with the scientific consensus.”
Yeah, I think Gore was misleading on this, and said so before.
9. It is not clear what Pacific nations Gore is referring to in the section dealing with evacuations to New Zealand. It is not clear that there is any evidence of evacuations in the Pacific due to human induced climate change.
[Worth knowing -W]