Over at OpenDemocracy.net they are running a special feature on debate on climate change. The "kick-off" pair of articles were by David King presenting the std.consensus view, and one by Benny Peiser who, lacking much to say, is obliged to puff up uncertainty. I ripped that up here. But what of David Kings contribution? Is that any good? Lets take a look...
Oops, first a caveat: I'm a climate modeller. So I can do that bit. I'm not so good at "impacts" and I try to steer clear of it. I'm going to be obliged to mention them in what follows, because DK does, but remember to devalue my opinions in those bits.
Headline: "Global warming: a clear and present danger". I'm a bit unhappy about that (see RealClimate post here) but I'll try to stick to the science (and its possible he didn't choose his headlines; but based on what follows, this is unlikely).
Bit of history (this-isn't-new) then "...global temperature increases of 1.5-6C for a doubling of carbon-dioxide levels". This may be the wrong numbers (see here) or maybe not - I'm not certain.
Mentions IPCC and Kyoto.
Nonetheless, it is often reported that scientists themselves cannot agree whether climate change is really happening, whether it is influenced by human activities and whether, even if both things are true, it really matters that much. The bad news is that this is for the most part a pseudo-debate. Tempting as it may be for some to believe that “it’s just the environmentalists doom-saying again”, the reality is that the overwhelming majority of credible scientific opinion is clear on all three points. Well, you have my opinion of the consensus via the RC link above. I think it includes the first 2 points, and a third (cl ch will continue) but is weaker on the fourth, impacts.
Beyond any reasonable doubt, climate change is happening. Fair enough.
Unmitigated climate change will both magnify humanity’s existing scourges – poverty, disease, famine – and add to these new ones, such as through increasing climatic extreme events, rising sea levels and flooding on a scale beyond human experience. Yeeeeeeesss ish. Less happy here: as above. Sea level is the only one I'm reasonable sure about: the IPCC mid value is about 0.4 m to 2100.
Part of the answer is in the nature of the media itself, which likes to present two sides of a story. “Scientists agree” is not such a great head line as “scientists at loggerheads”. Definitely agree.
There is also an issue that some, including some politicians, simply do not want to hear the evidence, regarding the implications as just too unpalatable (and politically unpopular) to be faced. Again, agree.
DK then goes on to examine groups of skeptics.
1: those basically scientists, but doubting. Lindzen as example. OK, as far as L's science writing goes; not true for his "popular" works.
2: small group of scientists who appear at every meeting but are not seriously regarded. Not familiar with this grouping.
3. very vocal group of professional lobbyists. Yes.
Summary: the balance of international scientific opinion is enormously in support of the conclusion that climate change is a real and present danger, requiring urgent and committed action. As above, I'd prefer a different description on the impacts side, but agree on the basic science side. [T]he arguments put forward by the sceptics gain publicity and influence far beyond that which can be justified by the standing of the individuals concerned, by the validity of their arguments, and by the scientific credibility of the evidence that they are able to put forward. To this I wholeheartedly agree.
Someone asked in particular about a French scientist who claims from a study of records of tea plantation companies in Tanzania that there has been no temperature increase around Kilimanjaro despite the loss of 85% of its ice cap (which has been dated back to the last ice age) over the past 100 years. I'm not familiar with this. From what I've heard, Kilimanjaro isn't a great example of anything: Kaser et al. suggests that the retreat of K's glaciers isn't directly temperature related. Others (no ref; sorry) suggest otherwise. But... so what? DK is correct to say that we shouldn't pay much attention to anyone "disproving" GW by looking at K; K is just one place; and whatever the mechanism for the glacier retreat there - T related or not - it won't say much about GW. For that, you want to look at glaciers globally: Eric Steig at RealClimate did that recently.
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