Quote:
Originally Posted by Skybird
August,
From all what science and research on past eras tells us, a rise of 0.8 °C in just 4 decades or so is racing down the autobahn with lightspeed - it represents a warming process taking place several hundred - sometimes it is even calculated as up to a thousand - times faster than in any previous eras about whose climatic conditions and changes we can make reasonably founded statements, basing on geologic findings for the most, or deep core drillings and deep ice drillings.
Taking a trip in the time machine and setting up sensors 200,000 years ago has little to do with it, August. Geology is a very interesting science, and there are other subbranches of sciences that focus on analysis of petrified seeds, for example - and maybe you underestimate how much such findings and the geological layers in which they are being found, can tell us about past conditions of climate and geography. Sediment analysis also can give us explicit information not only on the mix of agents in past atmospheres, but about the processes that made the content of the atmosphere change, and at what time. And both sciences combined, plus several others, allow us to make quite reasonable models of past climatic conditions. 
In fact some researchers in these fields say it is easier to reconstruct past atmospheric and climatic conditions, than to predict the change of the present climate.  |
Then they are telling untruths. Sorry, but the proxy data is
very weak.
In order to prove that their models (for relating proxy data to temperature) work, they must try and calibrate to known time periods. They don't work well. It also requires many assumptions about the past climate that are plausible, but again, unproved. It's a great science to be in cause you can say anything about the past (as long as that "anything" is that it's warmer NOW) and there is no possible way to check your answer to the same precision that we can measure temperature now.
BTW, the proxy models need to be able to be predictive, or they are simply wrong. You cannot claim the model accurately works as a proxy if it is not predictive.
Back in school we used to call astronomy (our field of study (well, astrophysics)) a "zeroith order" science. We did so because first terms in expansions were often as good an approximation as we were ever gonna get.
Climate science would be lucky to make the grade to be "zeroith order."
Not to say they shouldn't try, but they're just not there yet.
From a policy standpoint, all that matters is cost-benefit. To access cost of AGW, you need to have an accurate, predictive model (how can you mitigate, if you cannot say that an X% reduction means Y temperature change?)