Iowahawk has a step-by-step tutorial on how to reconstruct unavailable past temperature data from available past proxy data using statistical models built from available recent data.

All you need to do re-do the tutorial is:

1. A computer. Which I assume you already have, because you’re reading this.

2. The illustrative spreadsheet, available as an Open Office Calc document here, or as a Microsoft Excel file here. Total size is about 1mb.

3. A spreadsheet program. I highly encourage you to use Sun’s Open Office suite and its included Calc spreadsheet — it’s

free, very user friendly and similar to Excel, and it’s what I used to create the enclosed analysis. You can download and install Open Office here. You can do all of the examples in Excel too, but you’ll also need to download an additional add-on (see 4 below)4. A spreadsheet add-in or macro for principal components analysis. Open Office Calc has a nice one called OOo Statistics which can be download and installed from here. This is the macro I used for the enclosed analysis. If you’re using Excel, you’ll have to find a similar Excel add-in or macro for principal components analysis. There are several commercial and free versions available.