Apocalyptic global warming skeptics have long argued that the proponents of AGW have manipulated data to prove their case. (They then used the distorted temperature record to calibrate the General Circulation Models that were used to predict coming runaway temperature increases, so it is not a surprise that the GCMs have not demonstrated prediction competence.) Here from the blog Flopping Aces is a discussion and some video's on how the temperature record was distorted.