Supplemental material for the

Data

1. Noamer.m: The seventy North American tree ring records originally catalogued as auxiliary material by MM05. The records are identical with those used by MBH98. Slight modifications are made to the file so that it is Matlab readable.

2. Northern_Hemisphere_Temperature.m : Matlab readable version of the updated instrumental Northern Hemisphere Temperature estimate from from Jones and Moberg [2003]. See the file for full references.

3. Instrumental_Sparse.m: Matlab readable version of the Northern Hemisphere temperature records used by MBH98 and MM05 for calibration and verification.

Scripts

4. Mpca.m: Matlab script that normalizes the NOAMER data-set according to the MBH98, MM05, and fully normalized conventions. PCs and averages of the normalized data-set are computed and the figures included in the comment are generated.

5. Rscript.R: Modified version of the R script used by MM05 to produce figures and to estimate RE critical values and other statistic. All modification which I made are described in the code using the format "#PH, ...". Modification were only made to fix minor bugs (mostly associated with file paths) and to correctly compute the RE statistic. The original code omits a crucial normalization step when computing realization of the RE statistic. The modified code now computes RE values with the normalization step, referred to in the code as REfix. To get this code to run on your machine you will need to change the temp.directory on line 226 to a directory local to your computer. To download and install the R software see www.r-project.org. Note you will also need to have the waveslim package installed.

6. Monte_Carlo_RE.m: A simple Matlab example illustrating the discrepancy in MM05's estimate of the RE critical value.

Supporting functions

7. xcPH.m : cross-correlation.

8. rePH.m : reduction in error statistic.

9. phaserandomize.m : generates random records with an auto-correlation structure similar to the input record.

10. smoothPH.m : smooths a vector.

Notes

a. Matlab codes were run with version 7.0 on MAC OSX.

b. R codes were run with version 2.1.0 on Windows XP, [see cran.r-project.org]. Binaries for the waveslim package used by MM05 are only pre-compiled for Windows machines.