The NAO index is defined as the standardized (1901-1980) difference between the SLP average of four gridpoints on a 5x5 longitude-latitude grid over the Azores and over Iceland.
The reconstructions are based on a Principal Component Regression Analysis. More details can be found in Luterbacher et al. (2002)
Contact Juerg Luterbacher (juerg@giub.unibe.ch) for further information, for other reconstructed atmospheric circulation indices and for reprints.
| Filename | Size | Description |
|---|---|---|
| naomonjurg.dat | 60 kilobytes | Monthly 1659-Jul2001 |
| naoseajurg.dat | 10 kilobytes | Seasonal 1500-1658 |
|