This story is legitimately tragic, but it's far from the first case of climate change delusion. Have they never heard of Benny Peiser? Larry Solomon? Tim Ball? The Viscount Monckton of Brenchley? Bob Carter?
Of course, these guys may not be delusional. They may just be lying. But that would involve a judgment rather than a diagnosis …. And either way, a certain sort of sickness abounds.