Last year, Roger Harrabin, the BBC’s “energy and environment analyst”, retired. He tweeted as follows: “Only a month to go now before I leave BBC after 35 years. I did my last turn on Today Prog earlier. Felt very upset walking home. Not for me, but for the fate of the planet.”

On reading this, I burst out laughing. Although most journalists have delusions of grandeur, few of us think the fate of our planet turns on our individual career path. But I am glad Roger said it, because it displays succinctly the mentality which governs BBC coverage of climate change – very self-important, very emotional and very, very one-sided.

Since his release from BBC employment, Roger says frankly what he is. On Twitter, he describes himself as a “Green pioneer broadcaster”. That is an accurate phrase for how he did his job.

It does not seem to strike him as an odd way to work in a national broadcaster committed by Charter to impartiality. More to the point, it does not seem to strike the BBC as odd either. Yet it is like saying, “I’m a fascist broadcaster” (or a communist, Remainer or Leaver one): it declares a committed point of view. Roger Harrabin’s effective successor, Justin Rowlatt, seems, if anything, even more in thrall to his own beliefs. Who can forget his staring-eyed interview with Boris Johnson when he harangued the then prime minister for refusing to stop Britain’s solitary new coal mine?