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Information on sampling sites_
| Site code | Latitude (N) | Longitude (E) | Number of trees/cores | Elevation (m) | Aspect | Slope | Maximum tree-age | The rate of absent rings (%) | 
|---|---|---|---|---|---|---|---|---|
| BYH | 44.44° | 118.85° | 21/42 | ~1530 | NW | 30° | 224 (1791–2014) | 0.24 | 
| QMG | 44.20° | 118.77° | 20/40 | ~1310 | NW | 25° | 102 (1913–2014) | 0.36 | 
Statistics of chronologies from two sampling sites (BYH and QMG) and regional chronology (SGH) over common period 1950–2010_
| Statistic | BYH | QMG | SGH | 
|---|---|---|---|
| Standard deviation (SD) | 0.35 | 0.38 | 0.35 | 
| Mean sensitivity (MS) | 0.33 | 0.30 | 0.32 | 
| First-order autocorrelation (AC1) | 0.46 | 0.60 | 0.44 | 
| Interseries correlation (trees) | 0.40 | 0.47 | 0.33 | 
| Interseries correlation (all series) | 0.41 | 0.48 | 0.34 | 
| Mean within-tree correlation | 0.82 | 0.70 | 0.79 | 
| Signal-to-noise ratio (SNR) | 19.95 | 17.81 | 25.14 | 
| Expressed population signal (EPS) | 0.95 | 0.95 | 0.96 | 
| The first principal component (PC#1) | 0.44 | 0.52 | 0.37 | 
Coherence among annual total precipitation and annual mean temperature from three meteorological stations over the common period 1955–2012_ Correlation coefficients are listed_ Results for the original and first differences filtered climatic data are shown_
| Original (n = 59)/The first differences (n = 58) | ||||||||
|---|---|---|---|---|---|---|---|---|
| Annual total precipitation | Annual mean temperature | |||||||
| Balinzuoqi | Xiwuzhumuqinqi | Linxi | Balinzuoqi | Xiwuzhumuqinqi | Linxi | |||
| Balinzuoqi | / | 0.599 Significant at p < 0.01. Significant at p < 0.01.  | 0.638 Significant at p < 0.01. Significant at p < 0.01.  | / | / | / | ||
| Annual total precipitation | Xiwuzhumuqinqi | / | / | 0.646 Significant at p < 0.01. Significant at p < 0.01.  | / | / | / | |
| Linxi | / | / | / | / | / | / | ||
| Balinzuoqi | / | / | / | / | 0.904 Significant at p < 0.01. Significant at p < 0.01.  | 0.947 Significant at p < 0.01. Significant at p < 0.01.  | ||
| Annual mean temperature | Xiwuzhumuqinqi | / | / | / | / | / | 0.950 Significant at p < 0.01. Significant at p < 0.01.  | |
| Linxi | / | / | / | / | / | / | ||
Coherence among chronologies from two sampling sites over common period 1950–2014_ Correlation coefficients are listed_ Results for the original, high- and low-pass filtered chronologies are shown_
| Original | High-frequency | Low-frequency | |
|---|---|---|---|
| r | 0.572 | 0.681 | 0.501 | 
| p | < 0.001 | < 0.001 | < 0.001 | 
| n | 65 | 53 | 53 |