Radiosondes

A quick post, to recommend you to read this powerpoint presentation by Peter Thorne, Simon Tett, David Parker of the Hadley Centre, in particular slide 11, perhaps with the wiki Sat Temps page for background. FE is keen on the ppt - see his comment at RealClimate. For myself, I wouldn't over emphasise it - its a puzzle, to be sure, perhaps like the precession of the perihelion of mercury.