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Old 09-21-2013, 02:25 PM   #1068 (permalink)
Arragonis
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Quote:
Originally Posted by Alteredstory View Post
I'm not positive, but I think that's what he meant by hindcasting.
Not quite.

There are 2 types of models in this area - ones that recreate the past and ones that predict the future.

The recreation ones are created by comparing a proxy value (e.g. tree rings = temp) vs. tree rings and temp in the real world. You then verify the model against another period to see if it holds up. If it does you can then use it to recreate what happened before - I think this is type referred to here.

Climate models try and predict what will happen in the future given the variables we know about and can measure. So far the super dooper expensive ones that predict DOOM have failed, the simple basic physics one made by a bloke on paper in the 1920s works. Some of them seem to work backwards compared to reality - e.g. the UKMO one which has some parameters working more or less opposite to real world observations.

Modellers in the second type have not (as far as I know, maybe they have and I have missed it) attempted to hindcast the climate based on data from say 40 years ago to see if it matched what actually happened. It would be a valuable excersize if they did but even then there could be variables we still don't know about.

I'm not anti science, these modellers need more resources to refine the models and less pressure so they can make mistakes and try again - that's science - put up a theory with evidence and see if anyone can disprove it. The evidence here is weak at best.
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