Exactly; that's what I said.
Why, then, are you talking about the models' fit when answering the question of whether the "climate models can predict weather changes over long term periods" (emphasis mine)?
You make it sound as if they are just arbitrarily varying the parameters of the models to get a good fit.
Not arbitrarily, of course, but "varying the parameters of the models" is the most common and a very general method of getting "a good fit".
and seeing if the resulting predictions
Do you mean something like cross-validation? I don't think they predict the future in this context.
Why, then, are you talking about the models' fit when answering the question of whether the "climate models can predict weather changes over long term periods" (emphasis mine)?
What other way is there? Building a time machine?
How else can you estimate the suitability of models in making predictions than testing their past predictions on current data?
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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