SIGNAL CONVOLUTION, MIDPOINT OF RANGE, AND ALL THAT

KEVIN KILTY Introduction A guest blogger recently1 made an analysis of the twice per day sampling of maximum and minimum temperature and its relationship to Nyquist rate, in an attempt to refute some common thinking. This blogger concluded the following: (1) Fussing about regular samples of a few per day is theoretical only. Max/Min temperature…

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Nyquist, sampling, anomalies and all that

Guest post by Nick Stokes, Every now and then, in climate blogging, one hears a refrain that the traditional min/max daily temperature can’t be used because it “violates Nyquist”. In particular, an engineer, William Ward, writes occasionally of this at WUWT; the latest is here, with an earlier version here. But there is more to…

A condensed version of a paper entitled: “Violating Nyquist: Another Source of Significant Error in the Instrumental Temperature Record”.

By William Ward, 1/01/2019 The 4,900-word paper can be downloaded here: https://wattsupwiththat.com/wp-content/uploads/2019/01/Violating-Nyquist-Instrumental-Record-20190112-1Full.pdf The 169-year long instrumental temperature record is built upon 2 measurements taken daily at each monitoring station, specifically the maximum temperature (Tmax) and the minimum temperature (Tmin). These daily readings are then averaged to calculate the daily mean temperature as Tmean = (Tmax+Tmin)/2. Tmax…