Wood Romances

Recently I've seen people posting the following graph from Tony Heller, which is intended to show a cooling trend in temperatures following the 1940s and suggest that the "start of the satellite record" begins when temperatures are at their low point. Heller's graph is unsourced except for being called "Briffa's Reconstruction." This graph has shown up on Twitter, and so far I haven't seen any one identify the source of this data or even what the data represents. However, I was able to determine that up through 1960, the data is identical to Briffa 2001[1], and the data is on an Excel spreadsheet on an FTP site maintained by NOAA for plate 3 of Briffa's paper. The same site also has regional data that includes years following 1960 (plate 2 in Briffa's paper), but Briffa is clear that the post-1960 data does not have a clear temperature signal. Briffa writes, "The period after 1960 was not used to avoid bias in the regression coefficients...