It has recently come to my attention that there’s some difference of opinion on exactly what climate skeptics mean when they say that global warming is "part of a natural cycle," or more simply, "natural," as opposed to anthropogenic.

My assumption has always been as follows: The amount of CO2 produced by human activity is trivial as a climate forcing. It’s not causing the rise in global average temperature. The rise in global average temperature is simply part of a swinging between hot and cold that happens over centuries, and will happen no matter what we do. (Alternatively, recent warming is caused by an increase in solar radiation.)

The main practical outcome of the view that global warming is "natural" is that we can’t do anything about it (except adapt). I think that’s the whole point. But apparently not everyone agrees.

Does that jibe with what y’all think? Or are there other interpretations?

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