An Audit of the Creation and Content of the HadCrut4

More than 70 issues are identified, covering the entire process from the measurement of temperatures to the dataset’s creation, to data derived from it (such as averages) and to its eventual publication. The findings (shown in consolidated form Appendix 6) even include simple issues of obviously erroneous data, glossed-over sparsity of data, significant but questionable assumptions and temperature data that has been incorrectly adjusted in a way that exaggerates warming.