Fig. 2. Climatic interpretation of stalagmite δ¹⁸O.

Left: Comparison of the annually resolved DG7 δ¹⁸O record (A), observed EASM intensity index from 1948 to 2017 (3) (B), and normalized anomaly series of summer precipitation across North China (38) (C). Right: Comparison of the DG7 δ¹⁸O record, tree-ring δ¹⁸O record (39) (D), simulated annual precipitation δ¹⁸O (E), annual precipitation (F), and summer precipitation (G) in northern China (35°N to 42°N, 105°E to 120°E). DG7 record is the aquamarine line. Modeling results are from iCESM-LME (27). The black dashed lines indicate a second-order polynomial fitting for all records. The correlation coefficient is calculated with a 1-year equal interval interpolation and a 9-year moving average (significant at the P < 0.01 level). VSMOW, Vienna Standard Mean Ocean Water.