There has been much discussion recently about the adjustments made to past temperatures: see Paul Homewood's excellent posts on Paraguay, Bolivia and around the world; also from Shub; Brandon at WUWT and on his own blog; and a very readable summary by James Delingpole. All very interesting.
Jimmy Haigh, SandyS, Stephen Richards and Stewgreen allude to this topic's substantial history and quite rightly so - there are many bloggers and posts that could be mentioned (see the James Delingpole article). Though this particular cartoon was inspired by Paul Homewood's recent post I think there is lot more to come on this story.