Read here. The NASA temperature data series produced by the James Hansen and Gavin Schmidt is considered to be worthless by experts, as expressed in Climategate emails written by other major climate alarmist scientists (Jones & Wigley). (Hat Tip.) The crappy data produced by NASA is likely to have resulted in their own climate models totally missing the recent global cooling (or, maybe it was due to the AGW CO2-hypothesis being worthless, hmmm....).
As further recent evidence that the NASA temperature data is the epitome of a "climate science" joke, how could the Arctic be warming so much this past winter, as the below image shows, yet most of the Northern Hemisphere experienced a stunningly cold and bitter winter? Go here for an answer to this NASA temperature data bungling. Update here. (click image to enlarge)