And find that it doesn't talk about forecasts, it is predominantly concerned with whether models can reproduce historically observed features of the climate
Exactly; that's what I said.
EDIT: To clarify, I'm trying to say that past models have had a good fit to data so far, so it's reasonable to expect they will continue to perform. This is certainly evidence towards climate models being able to carry out predictions, and it's how science should be done.
In other words, the issue is just trying to get a good fit to historical data.
You make it sound as if they are just arbitrarily varying the parameters of the models to get a good fit. In reality, they are using model ensembles for various different emissions scenarios obtained from real-world data and seeing if the resulting predictions fall within a reasonable confidence interval of what was actually observed. The answer is: yes, they do.
By the way, if you look at p.771 and around, you'll notice that the models have a lot of difficulties with the current "hiatus".
There are several ways of interpreting this; I'd be glad to have a discussion about it if you're interested.
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-...
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