The central issue is “sensitivity”

The central issue is “sensitivity”: the amount of warming that you can expect from a doubling of carbon dioxide levels. On this, there is something close to consensus – at first. It is 1.2 degrees centigrade. Here’s* how the IPCC put it in its latest report.

“In the idealised situation that the climate response to a doubling of atmospheric CO2 consisted of a uniform temperature change only, with no feedbacks operating…the global warming from GCMs would be around 1.2°C.” Paragraph 8.6.2.3.

Now the paragraph goes on to argue that large, net positive feedbacks, mostly from water vapour, are likely to amplify this. But whereas there is good consensus about the 1.2 C, there is absolutely no consensus about the net positive feedback, as the IPCC also admits. Water vapour forms clouds and whether clouds in practice amplify or dampen any greenhouse warming remains in doubt.

So to say there is a consensus about some global warming is true; to say there is a consensus about dangerous global warming is false.