I do see your point - it does help when folk explain what they mean rather than simply throwing out bald assertions and buzz words :lol: I'm not sure how accurate that would be as a criticism though. After the 40s/60s low, presumably all the proxy plots would return to an upward trend (most clearly visible in the red), some of which may be obscured by the black plot (the author says the most recent data is put towards the front). Moreover some of the proxy graphs end as early as 1960 or 65 and only two of them go beyond 1991 (ending in 92 and 95 to be precise), whereas the 5-year average up to 2000 is boosted by the highs in 98, 01 and 02. The only plot I can definitely see ending significantly lower
and not much earlier than the instrumental one is light turquoise (831-1992), and as noted above that's one of the ones which depends significantly on tree-ring data - obviously red (also a tree-dependant graph) also ends much lower, though it only goes to 1979.
I'm an Aussie, so I'd have a go at Vodafone myself
Despite being imperfect, as you've noted the instrumental record goes back to the 1880s, which allows for a century or more against which to compare proxy data. According to Wikipedia
borehole data doesn't need to be calibrated, though I'm rather sceptical of that (and of the borehole idea generally for that matter, but what do I know?). But certainly things like tree or coral growth, sedimentation, stalagmite coloration and so on do not reveal temperatures in and of themselves - those patterns must be compared with known temperature patterns first to establish a semi-reliable correlation and then to calibrate, to decide that
this amount of growth means
that kind of temperature and so on.
The whole enterprise seems rather uncertain to my mind. But then my slightly less science-curious brother says the same about radiometric dating, so in my ignorance I'll just have to assume that the experts know what they're doing with cross-comparison and so on :lol:
And AGAIN I point out that in the case of the modern discussion we are looking at the global
average temperatures.
Those are all local proxies.
"
The main figure shows eight records of local temperature variability on multi-centennial scales throughout the course of the Holocene, and an average of these (thick dark line)."
At different times, some of those local proxies are higher than the current global averages. Of course they are. Around half of the local temperatures are going to be higher than the global average today too! (Actually I'm not sure how that will relate to
anomalies, but it's 3am so bugger it.) But that graph does show the averages of those local proxies, and while it's obviously a very poor substitute for the more comprehensive data available these days, that average plot does not reach current levels either in temperatures or in rate of change (except perhaps over 10,000 years ago).
You're the one who posted it earlier :roll: I've heard of attacking a strawman, but it's not often you see someone attributing
their own choice of evidences to the other side.
Thanks for your responses, anyways. As noted, I reckon I'll be calling it quits on the global warming discussion now - I think I've learned enough to conclude that scepticism and denial of the conclusions of most climatologists does not appear to rest on very solid ground. Hell, you (who I've so far respected) have decided to simply claim that climatology isn't even science (or as much science as astrology)! But I've learned plenty of other stuff too, for which I thank you and Flogger. I never did get 'round to learning enough to personally make a particularly compelling case for AGW admittedly, beyond the rather feeble threat of two extra degrees' warming from CO2 alone if our emissions remain stable... in a mere 170-odd years :shock: But I've got a better handle on how much there is to learn about the science (and about the critics) if I ever want to do so!
