Dendroclimatology from Regional to Continental Scales: Understanding Regional Processes to Reconstruct Large-Scale Climatic Variations Across theWestern Americas - Dendroclimatology - page 214

Fig. 7.15 Spatial correlation patterns between 297 Palmer Drought Severity Index (PDSI) recon-
structions across North America (Cook et al. 2004 ) and( a ) El Niño-3 region temperature
reconstruction (Mann et al. 2000 ) ; ( b ) tree-ring variations from the precipitation-sensitive El
Asiento Austrocedrus chronology, Central Chile; and ( c ) composite Polylepis chronology from
Caquella and Soniquera in the Bolivian Altiplano
As was mentioned above, the tree-ring records used in the Niño-3 reconstruc-
tion are not completely independent of those used in the PDSI reconstructions,
but the resulting spatial correlation pattern provides the basis for the search for
commonalities with spatial patterns from comparison with the central Chile and
the Bolivian Altiplano chronologies.
Figure 7.15b , c shows the spatial correlation patterns for the central Chile and
altiplano chronologies with reconstructed PDSI over the 1650-1980 time period
common to Niño-3 index reconstruction. Significant correlations are observed in the