Quelccaya accumulation are 2 of only 14 proxies in MBH99. I think that it was the very first Mann proxy series that I posted about (circa May 2003), as the underlying data looked very strange when plotted. Hans Erren has posted up an interesting analysis which both explains the strange appearance of the series as an aliasing effect and Thompson never digitized key aspects of the underlying data set and has no plans to do so. I’ve mentioned elsewhere that Thompson has distributed 3 different and inconsistent versions of the Dunde data and has not archived original data for Dunde, Guliya and Dasuopu. Someone really needs to tie strings to the mittens of the Hockey Team.
See here. Aliasing artifact illustrated as follows: