Characterized as a climatologically sensitive region, the southeastern Tibetan Plateau (STP) is an ideal location for dendrochronological research. Here, five tree-ring width (TRW) chronologies were developed: three for Picea likiangensis along altitudinal gradients from 3600 to 4400 m a.s.l. and two for Sabina saltuaria and Abies squamata from 4200 m a.s.l. Significant differences in the growth rates and age composition of Picea likiangensis were observed at various elevation gradients. The chronology statistics (mean sensitivity, etc.) fluctuated with the elevation gradient. Picea likiangensis showed distinct growth patterns in response to climatic variability along the altitude gradient: the minimum temperature influenced tree growth at lower and middle altitudes, while higher altitudes were affected by precipitation. The radial growth of different tree species growing in the same region is controlled by the same climatic factors. Sabina saltuaria and Abies squamata exhibited similar growth responses to Picea likiangensis. Stand conditions (wind speeds, slope, and elevation) and biotic factors (the depth of root, forest type, tree age, and sensitivity) can partially explain why the ring width–climate relationships change with altitude.

Two annually resolved and absolutely dated Juniperus saltuaria (JS) tree ring width chronologies from the Haizi mountain, southeastern TP were reported in here. We sampled two sites in different landscapes, one is located at the forest line at ca. 4200 m above sea level beside an incised valley, and the other at the plateau surface, ca. 4500 m in elevation. Comparisons of statistical parameters between two sites and their tree ring index correlation coefficient with meteorologic data of DaoCheng shows that the latter site exhibits higher value than the former one. These indicate that those trees growing along the valley side may be more susceptible to local environment, and those on the plateau surface can provide reliable record for regional climate. Based on the latter chronology, a 903a long annual mean temperature (Tmean) series (1115-2017 CE) was reconstructed. It is the longest width chronology reconstructed by JS at present. The entire sequence shows consistent warm-cold patterns with other temperature reconstructions of the TP, Asia, and Northern Hemisphere. The warmest (coldest) period occurred at 1998-2017 CE (1115-1145 CE), respectively. There was no doubt that temperature raised sharply since the end of the 20th century. In addition, the sequence demonstrates multi-decadal, decadal and inter-decadal variations, further multi-taper method reveals dominant periodicities are 147, 36, 18, 7 and 2-2.6a, likely been affected by the Atlantic Multidecadal Oscillation and solar activity. The forcing of volcanic eruptions resulted to subsequent 1-3 years temperature drops.