Dear Geoffrey Lean, let me explain why we're so cross…

My colleague Geoffrey Lean is upset by the vitriol he attracts on the internet. I feel for him. Though I have never met Geoffrey colleagues tells me he's a delightful fellow who means very well. I'm sure he does and, though our views on AGW are very different, I take no more pleasure in seeing him taken to pieces by Telegraph-reading sceptics than I do from all the charming emails I get from George Monbiot groupies calling me something beginning with "C". (And it's shorter than "Climate...