Annual temperature reconstruction in the central Hengduan Mountains, China, as deduced from tree rings

We developed five tree ring-width chronologies from one fir (Abies georgei) and four spruce (Picea brachytyla) stands near the upper treeline in the central Hengduan Mountain, northwestern Yunnan, China. Similar growth patterns and significant correlations are embodied among the five chronologies. A principal component analysis for the four spruce chronologies indicated that the first component accounts for 54.8% of the total variance over the period 1750-2003. Climate-growth response analysis revealed that radial growth is mainly controlled by temperature variations, especially in the winter season. The first principal component of the spruce chronology network accounts for 43% of the annual mean temperature (from previous October until September) variance during the common period 1959-2003. By using a linear regression approach, we reconstructed annual mean temperature for the past 250 years. The reconstruction shows that the central Hengduan Mountain experienced some cool episodes during the 1810s, 1860s, and during 1960-1980. Warm intervals occurred during the 1780s, 1850s, 1940-1960 and in the past two decades. These general patterns are in general accordance with other records from nearby regions. (C) 2008 Elsevier GmbH. All rights reserved.