Official Average U.S. Temperature Increases by 0.5 Degrees F

I have long wondered how the average temperatures were calculated. I already knew it was based on a 30-year period, but not the specifics.

Something to note is that since temperatures are rising, and therefore the average is rising, comparing the current temperature to the "average" will hide some of the on-going increases of temperature. This is not due to any conspiracy, but simply the mathematics. Of course, it does help those who are in the conspiracy to hide the problem.

http://www.sciencedaily.com/releases/2011/06/110629205053.htm

ScienceDaily (June 30, 2011) — According to the 1981-2010 normals to be released by NOAA's National Climatic Data Center (NCDC) on July 1, temperatures across the United States were on average, approximately 0.5 degree F warmer than the 1971-2000 time period.

Normals serve as a 30 year baseline average of important climate variables that are used to understand average climate conditions at any location and serve as a consistent point of reference. The new normals update the 30-year averages of climatological variables, including average temperature and precipitation for more than 7,500 locations across the United States. This once-a-decade update will replace the current 1971-2000 normals.

In the continental United States, every state's annual maximum and minimum temperature increased on average. "The climate of the 2000s is about 1.5 degree F warmer than the 1970s, so we would expect the updated 30-year normals to be warmer," said Thomas R. Karl, L.H.D., NCDC director.

Using standards established by the World Meteorological Organization, the 30-year normals are used to compare current climate conditions with recent history. Local weathercasters traditionally use normals for comparisons with the day's weather conditions.

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