North Atlantic Oscillation Reconstruction
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               World Data Center for Paleoclimatology
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NOTE: PLEASE CITE ORIGINAL REFERENCES WHEN USING THIS DATA!!!!!
NOTE: This reconstruction is considered obsolete.  See discussion below.

CONTRIBUTORS: Cook, E.R., D'Arrigo, R.D., and Briffa, K.R.
NAME OF DATA SET:  North Atlantic Oscillation Reconstruction

LAST UPDATE:  This reconstruction is considered obsolete.  Newer and
well-verified multi-proxy NAO reconstruction of Cook et al. 2002 
is now available on this server as file nao_cook2002.txt.  Please see
http://www.ngdc.noaa.gov/paleo/pubs/cook2002/cook2002.html
for details and discussion.

IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 1998-037.

SUGGESTED DATA CITATION: Cook, E.R., D'Arrigo, R.D., and Briffa, K.R., 1998, 
North Atlantic Oscillation Reconstruction.  
International Tree-Ring Data Bank.  IGBP PAGES/World Data Center-A for 
Paleoclimatology Data Contribution Series #1998-037.  
NOAA/NGDC Paleoclimatology Program, Boulder CO, USA.

ORIGINAL REFERENCE:
Cook, E.R., D'Arrigo, R.D., and Briffa, K.R., 1998, A reconstruction of the 
North Atlantic Oscillation using tree-ring chronologies from North America 
and Europe, The Holocene 8(1): 9-17. 

ADDITIONAL REFERENCES:
D'Arrigo, R.D., Cook, E.R., Jacoby, G.C., Briffa, K.R. 1994, NAO and sea surface 
temperature signals in tree-ring records from the North Atlantic sector. 
Quaternary Science Reviews 12: 431-440. 

D'Arrigo, R.D., Jacoby, G.C., Cook, E.R. 1992 Impact of recent North Atlantic 
anomalies on surrounding land areas based on dendroclimatic evidence. 
Geophysical Research Letters 19(23): 2321-2324. 

LAST UPDATE:  10/98 (Original receipt by WDC-A Paleo)
GEOGRAPHIC REGION: North Atlantic
PERIOD OF RECORD: 1700 - 1980 AD

LIST OF FILES: NAO.readme.txt (this file), NAO.recon.txt.

DESCRIPTION:
This reconstruction is considered obsolete.  Newer and well-verified 
multi-proxy NAO reconstruction of Cook et al. 2002 is now
available on this server as file nao_cook2002.txt.  Please see
http://www.ngdc.noaa.gov/paleo/pubs/cook2002/cook2002.html
for details and discussion.

Tree-ring records, six from eastern North America and four from northwestern Europe, 
are used to develop the first reconstruction of the winter North Atlantic 
Oscillation (NAO). The reconstructed series spans the interval AD 1701-1980 and 
explains 41% of the variance in the NAO over the AD 1874-1980 calibration period. 
The reconstruction also captures the spectral properties of this index, 
suggesting that the oscillatory character of the NAO is a 
long-term feature of the North Atlantic climate system. 

Low frequency varability (8 years or greater) in the reconstruction is of greater 
reliability than high frequency (i.e. annual) variability, which is potentially 
affected by processing.  See the Original Reference for full discussion of the model.