Erroneous geographical locations of precipitation proxies have been source of mild amusement to CA readers. Long ago, in connection with MBH, we observed that the rain in Maine fell mainly in the Seine – an error that Mann stubbornly refused to correct in Mann et al 2007 – not that any reviewer cared.
A few weeks ago, we observed with mild amusement that, as Liza Doolittle knew, the rain in Spain fell mainly in the plain – except that in Mann-world, it fell in the plains of Kenya.
Shortly afterwards, Mann reported the corrected the error without acknowledging the source – even though proper acknowledgment of sources is mandatory under Penn State codes of conduct.
I reported the error more as a matter of amusement, and this largely because of the prior history with the rain in Maine. But here’s something a little more substantial – Mann corrected the error and re-did his calculations. Below is a figure showing the impact of correcting the location of one proxy on his SH reconstruction. The difference in the 18th century is over half a degree, as shown below.
We sometimes are told that the various errors don’t “matter”. But here’s a case where merely changing the location of one proxy from Kenya to its correct location in Spain alters the estimate for the SH by about 0.5 deg C for an entire century. Oh yes, at the NAS panel hearings, Mann said that he knew the AD1000 temperature within 0.2 deg C.