According to the best-sited stations, the diurnal temperature range in the lower 48 states has no century-scale trend.

It seems that a number of folks have missed one of the more important conclusions from our first paper on the surfacestations project. Co-author Dr. John Nielsen-Gammon has some things to say about it the finding that is the title. For layman readers that don’t know what diurnal variation is, it is the daily variation…