Sunshine duration reconstruction in the southeastern Tibetan Plateau based on tree-ring width and its relationship to volcanic eruptions

(a) The reconstructed monthly sunshine duration series from the prior September to the current June during 1517-2013 CE (gray line), an 11-year moving average (black line), the long-term mean (black horizontal line), and the mean value ± 1σ (gray horizontal lines); (b) 30-year (gray line) and 50-year (black line) running variance for reconstructed.86