I think I will start to close down comments on some of the guide articles as the comment threads get too long and meandering, and instead direct people from there to dedicated “open threads”.
So consider this the first implementation of that idea for the article “CO2 Lags, not leads“. Comments there are now closed.
The main reason I want to do this article first, aside from the recent explosion of unproductive comments, is because I would like to make a correction and a couple of clarifications based on what came out there. The majority of the comments fall squarely in the “completely missing the point” category, in that they simply restate the addressed objection with not even a cursory nod to the refutation. We can ignore those.
But I think that if I wrote the article today there is in fact one thing I would change. I wrote:
So, it is correct that CO2 did not trigger the warmings, but it definitely did contribute to them, and according to climate theory and model experiments, greenhouse gas forcing was the dominant factor in the magnitude of the ultimate change.
It is this last phrase that I would alter. There is research that purports to show up to 90% of the warming/cooling of the glacial-interglacial cycles was due to GHG’s, but there is also research that pegs this factor at much less, around 30%. Given that, I would like to change “greenhouse gas forcing was the dominant factor” to “greenhouse gas forcing was a dominant factor”. This is more conservative but therefore much easier to justify and it in no way detracts from the argument. As mentioned in the original article, albedo changes from melting/growing ice sheets and orbital forcing are the other major factors.
The clarification I would like to make is in two parts: part one is that the evidence gleaned from the polar ice core records is not “proof” of GHG driven warming. I do not make that claim and no one should, but this is the straw man frequently erected around the ice core records. It is however entirely consistent with the current theories. This is all that is required of good theories and available data. As well, modeling experiments (is there another way?) confirm that GHG forcing is absolutely required to explain the magnitude of the temperature swings. Part two is that the evidence gleaned from the polar ice core records, specifically that orbital forcings come first, is categorically not proof that CO2 does not cause any warming or even not much warming. This is the biggest and most obvious mistake that denialists make, assuming that because orbital forcing happens first therefore GHG forcing does not exist.
Otherwise, I think the article is fine. This thread is where any further discussion should take place.