Temperature sensitive paleoclimatic multi-proxy data from 17 sites worldwide were used to generate thousand year long records of temperature for both hemispheres. Proxy types include tree rings, ice cores, corals, and historical documents.
The data contain the original series in normalised units as well as anomalies in Degrees C vs 1961-90 mean.
P.D. Jones, K.R. Briffa, T.P. Barnett, and S.F.B. Tett, 1998, "High-resolution Palaeoclimatic Records for the last Millennium: Interpretation, Integration and Comparison with General Circulation Model Control-run Temperatures", The Holocene 8, 1998, 455-471.