Tree-ring density inferred late summer temperature variability over the past three centuries in the Gaoligong Mountains, southeastern Tibetan Plateau

Long and high-resolution proxy records are still sparse in the southeastern Tibetan Plateau (TP), hampering our understanding of past climatic variability from a long-term perspective. In this study, we developed a regional maximum latewood density (MXD) chronology of Larix speciosa stretching up to 523 years based on 72 tree-ring cores (44 trees) collected from three sites close to the tree line in the Gaoligong Mountains, southeastern TP. This chronology responded well to temperatures during August through September and was thus used to reconstruct late summer (August–September) temperature over the period A.D. 1690–2008. The reconstruction explains 40.9% of the total temperature variance during the calibration phase. Cold conditions prevailed during the periods 1695–1702, 1806–1821, the 1850s, 1882–1889, the 1900s and the 1960s. Warm phases occurred in 1734–1745, the 1770s, 1824–1840, the 1890s, 1927–1936, the 1940s–1950s and 2002–2008. Spatial correlation with the gridded temperature data set showed that our reconstruction captures large-scale regional temperature variations for the southeastern and southern TP. Comparison with other tree-ring inferred temperature time series in the surrounding areas, glacier fluctuations and historical documental records imply a high degree of confidence for our reconstruction.