North Atlantic Oscillation Reconstruction: Readme file
---------------------------------------------------------------------
                   NOAA Paleoclimatology Program
                               and
              World Data Center for Paleoclimatology, Boulder
---------------------------------------------------------------------
NOTE: PLEASE CITE ORIGINAL REFERENCE WHEN USING THIS DATA!!!!!

NAME OF DATA SET: North Atlantic Oscillation Reconstruction
LAST UPDATE: 3/2002 (Original Receipt by WDCA Paleo)  
CONTRIBUTOR: Juerg Luterbacher, University of Bern, juerg@giub.unibe.ch

IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2002-016

SUGGESTED DATA CITATION: Luterbacher, J., et al., 2002,
North Atlantic Oscillation Reconstruction. 
IGBP PAGES/World Data Center A for Paleoclimatology 
Data Contribution Series #2002-016. 
NOAA/NGDC Paleoclimatology Program, Boulder CO, USA. 

ORIGINAL REFERENCE: 
Luterbacher, J., Xoplaki, E., Dietrich, D., Jones, P.D., Davies, T.D., 
Portis, D., J.F. Gonzalez-Rouco, H. von Storch, Gyalistras, D., Casty, C., 
and Wanner, H., 2001, 
Extending North Atlantic Oscillation Reconstructions Back to 1500. 
Atmos. Sci. Lett., 2, 114-124, doi:10.1006/asle.2001.0044. 

GEOGRAPHIC REGION: North Atlantic 
PERIOD OF RECORD: 1500 AD - 2001 AD

LIST OF FILES: Readme_Luterbacher2002b.txt (this file),
nao_mon.txt, nao_sea.txt.



DESCRIPTION:
Reconstructed monthly NAO index back to December 1658 and seasonal estimates 1500-1658. 

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. (2001) 
Contact Juerg Luterbacher (juerg@giub.unibe.ch) for further information, 
for other reconstructed atmospheric circulation indices and for reprints. 

Note: This file updated 10/13/2015 to correct publication year error (2002 corrected to 2001)


ABSTRACT:
Monthly (1659-2001) and seasonal (1500-1658) North Atlantic Oscillation (NAO) indices 
were estimated using instrumental and documentary proxy predictors from Eurasia. 
Uncertainty estimates were calculated for the reconstructions, and the variability 
of the 500-year winter NAO has been assessed. The late twentieth century NAO extremes 
are within the range of variability during earlier centuries.