Fig. 5.

Climate reconstructions over the last four centuries. The 5-yr averages of δ¹⁸O (A) and accumulation (B) for seven and five low-latitude ice cores, respectively, were reconstructed back to A.D. 1600. Accumulation is given in meters of water equivalent (w.e.) per yr. Annual layers (and hence A_n) were not reconstructed for Huascarán and Sajama as discussed in the text. Composite δ¹⁸O and A_n records for the TP (C) and Andean (D) cores were combined to produce low-latitude composite δ¹⁸O and A_n histories (E) for the last 400 yr. The composite records are shown as Z-scores. Data are provided in Data Set 2, which is published as supporting information on the PNAS web site.