Via WUWT, Jeff Id takes a look at the GHCN temperature data base, specifically comparing warming in urban vs. rural locations. As found in a number of other studies, about half of 20th century warming int he surface temperature record may be due to uncorrected urban biases.
Some past takes on the same subject:
- Ross McKitrick has delivered this same finding several times
- LaDochy et al found similar results for California
- Even Phil Jones finds as much as 40% of warming in his data base from urban bias, though he tries to disguise the finding.
- Even a kid can demonstrate it.
- Actually, even my kid can demonstrate it.