The IPCC actually admits the possibility of lukewarming within its consensus, because it gives a range of possible future temperatures: it thinks the world will be between about 1.5 and four degrees warmer on average by the end of the century. That’s a huge range, from marginally beneficial to terrifyingly harmful, so it is hardly a consensus of danger, and if you look at the “probability density functions” of climate sensitivity, they always cluster towards the lower end.
What is more, in the small print describing the assumptions of the “representative concentration pathways”, it admits that the top of the range will only be reached if sensitivity to carbon dioxide is high (which is doubtful); if world population growth re-accelerates (which is unlikely); if carbon dioxide absorption by the oceans slows down (which is improbable); and if the world economy goes in a very odd direction, giving up gas but increasing coal use tenfold (which is implausible).
But the commentators ignore all these caveats and babble on about warming of “up to” four degrees (or even more), then castigate as a “denier” anybody who says, as I do, the lower end of the scale looks much more likely given the actual data. This is a deliberate tactic. Following what the psychologist Philip Tetlock called the “psychology of taboo”, there has been a systematic and thorough campaign to rule out the middle ground as heretical: not just wrong, but mistaken, immoral and beyond the pale. That’s what the word denier with its deliberate connotations of Holocaust denial is intended to do. For reasons I do not fully understand, journalists have been shamefully happy to go along with this fundamentally religious project.