SEARCH BLOG: GLOBAL WARMING
Steve McIntyre, at Climate Audit, does an analysis of the recorded U.S. average temperature change from 1920 to present which amounts to 0.21° C. He then uses the words of Drs. Schmidt and Hansen of NASA that the recent downward adjustments of 0.15° C to the temperature records does not matter to make the point that the minuscule change over 80+ years is irrelevant.
I'd like to point out that the starting point is relevant. If you use 1880, a relatively cold period in the U.S., then you go from a low point in the record's oscillation to a high point. I suggest that what is shown from the record is, at best, a flat trend with a high point in the 1930s and another high point in the late 20th century. Whatever warming that may have occurred is primarily in the moderation of cold temperatures from the coldest periods of the weather history... or faulty siting of weather stations, a subject that has been discussed in detail at Anthony Watts' site, that give the illusion of a moderation of cold temperatures.It's an old trick of marketers and sales reps to pick a starting point that makes whatever they are presently doing look as different [positive] as possible. It's not necessarily good science, however.
Nevertheless, Steve McIntyre's point is a very good one.