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Originally Posted by renormalised
It hasn't been stable, in any terms. Actually, the global average temperautures for most of the last 550ma have been far more stable, for vastly longer periods of time than now. During the Cretaceous, the global average temperature remained at around 18 degrees (6 above now) for almost 100 million years!!!. 6-10 degree up and down fluctuations over a 600Ka period don't even count.
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Ah but they do, obviously you are right about the long term stability and my use of the word is a poor choice, lets say "predictable" instead (though that has connotations I wouldn't use...), but if you have a steady up/down cycle (and on a gross scale it has been fairly steady for the last 4 ice ages at least) and then suddenly depart from it I would be worried. The fact that it varied in a different way much further back in time wouldn't make me feel any better about it.
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Originally Posted by renormalised
They are now, and in the last 50 or so years, but what about the preceding 100 or so years...and they've only had the use of radiosondes for atmospheric measurements since the mid to late 40's. Satellites for even less time. The data isn't as good or as complete as it should be.
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Well, the data is as good as it can be and we can only work with what we can get. We can't get satellite or balloon measurements for the last million years, so we have to work with what we have and in my opinion the human inginuity used in estimating temperatures from many different fields in many different ways is remarkable. Especially as most (but by no means all) agree to quite a degree.
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Originally Posted by renormalised
The only way to know what the modellers have used in their models is to look at the algorithms used and the assumptions they've used in making the models. Some may have included deforestation, others may not. What interests me is though there are other factors which are contributing to climate change in just as important ways as CO2, why is there an almost religious belief in the cause being "only" CO2 emissions. That's how it appears to being played out.
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Well, that is perhaps true of the media, I don't think it is true of the science. When i was working for the CRC for Greenhouse Accounting other gases were being looked at and the IPCC report has plenty on other gases too. The increasing concern about methane is an obvious part of that. Land use change is certainly a major factor in greenhouse accounting and a big sticking point right now in Copenhagen.
A lot of the algorithms used do get published in peer reviewed papers (dunno what proportion), it's just that by publication they tend to be somewhat behind the cutting edge.
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Originally Posted by renormalised
Yes, nearly correct there...what I'm trying to get at is that the impact of the riding CO2 levels isn't the be all and end all of what's changing the climate. There are other factors just as important which are contributing but you hear very little about them. All you get is the CO2 bogey man and very little else. There's a lot more to the results being published than pure academic study and reporting and I think those leaked emails recently, have established that and don't believe for one minute it's only confined to those scientists involved. They have done the whole debate a complete disservice and science no favours either. If I was the chancellor of the university/ies they were at, I would have dragged them before an university council and made them explain themselves. If they didn't have a damn good answer to back themselves up (which they wouldn't), they'd have been charged with gross misconduct and had their tenures revoked. I'd have sacked them immediately and advised the governments not to take their studies on their word, or anyone else associated with their studies...that includes the IPCC, which they were a part of.
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I think the email leak is overplayed. It certainly isn't good and it has certainly done science a disfavour. But to some extent it just reflects reality. We scientists are people, personal politics, have dissagrements and have to fight over funding etc. We aren't a perfect science machine. I don't think there is anything there that casts doubt on the publicly released results.