We provide in this directory:


1. Instrumental surface temperature eigenvectors (EOFs and PC series) 
computed over the interval 1902-1993, corresponding eigenvalues 
('tpca-eigenvalues.out', first 2 columns). The first 16 eigenvectors were 
retained, and the EOF patterns (loadings) are contained in files eofxx.out 
where xx=1,..,16. The annual mean Principal Components (PC) time series 
are contained in pcxx.out, where xx=1,..,16, 

2. Gridbox locations for the 1082 instrumental surface
temperature gridpoint series used for calibration ('gridpoints-cal.loc').
The order of spatial coordinates for the 1082 spatial
loadings in the EOF patterns (see "1" above) is the same as in
this file. In addition, the locations of the 219 gridpoints used for
verification over the 1854-1901 interval are provided in
'gridpoints-ver.loc'. 

3.  Gridbox temperature standardization factors (standard deviations of monthly 
mean anomaly series over 1902-1993 period) used to normalize the 1082 instrumental 
gridpoint series ('tpca-standard.out', 2nd column). Order of gridpoints same as 
in "2" above.

4.  The Climatic Research Unit (CRU) gridpoint surface temperature 
dataset ('anomalies-new') from 1854-1993 of Jones and Briffa [1992] used by MBH98 
(this version of the dataset has been replaced by a different surface temperature 
dataset at the CRU website and is no longer available). 

5. A simple fortran program ('getdata.txt') to read in the data
contained in 'anomalies-new'. MBH98 made use of all nearly continuous
monthly gridpoint surface temperature records [1082 gridpoints containing
no single gap greater than 36 months in duration over the 1902-1980
period used for calibration, and a subset of 219 gridpoints available
back to 1854 with no single gap greater than 24 months in duration,
and no more than 10 years (120 months) of total missing values over the
1854-1980 period, for verification]. Any remaining gaps were
linearly interpolated.