• Tree-Ring Based Drought Reconstruction (A.D. 1855-2001) For The Qilian Mountains, Northwestern China

      Tian, Qinhua; Gou, Xiaohua; Zhang, Yong; Peng, Jianfeng; Wang, Jinsong; Chen, Tuo; Center for Arid Environment and Paleoclimate Research (CAEP), Key Laboratory of Western China’s Environment Systems MOE, Lanzhou University, Lanzhou, 730000, China; Graduate School of the Chinese Academy of Sciences, Beijing 100039, China; Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China; The State Key Laboratory of Loess and Quaternary Geology, The Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China (Tree-Ring Society, 2007-06)
      A juniper (Juniperus przewalskii Kom) tree-ring width chronology has been developed from the western-most forest of the Qilian Mountains. Our analyses demonstrate both temperature and precipitation have significant effects on tree growth and that both should be considered in climate reconstruction. Thus a regional drought history (A.D. 1855–2001) is reconstructed by calibrating with a linear interpolation through four Palmer Drought Severity Index (PDSI) grid values nearest the sampling site. Our reconstruction extends the drought history of this area and also reveals that the most severe drought occurred in the 1920s. In the context of the drought history of western China, this extreme drought between 1925–1931 is consistent over a large surrounding region of Northwestern China. Multi-taper spectral analysis reveals the existence of significant 40- to 46-year, 29-year, and 2.1- to 3-year periods of variability. Overall, our study provides reliable information for the research of past drought variability in the Qilian Mountains, Northwestern China.
    • Tree-Ring Dating of Sinmu-Mun, The North Gate of Kyungbok Palace in Seoul

      Park, Won-Kyu; Kim, Yo-Jung; Seo, Jung-Wook; Lee, Jin-Ho; Wazny, Tomasz; School of Forest Resources, Chungbuk National University; Institute for the Study, Conservation and Restoration of Cultural Heritage, Nicholas Copernicus University of Torun (Tree-Ring Society, 2007-12)
      The cutting dates of 10 wood timbers (girders and corner rafters) of Sinmu-mun, the north gate of Kyungbok Palace in Seoul, were determined by the dendrochronological method. Tree-ring chronologies of unknown dates derived from the timbers were crossdated using the graphic comparison method against the dated master chronologies derived from living trees. The living trees for the masters used for this study were Pinus densiflora Sieb. et Zucc. (Japanese red pine), a major timber species for Korean traditional buildings. By comparing the Sinmu-mun samples with the masters from the western Sorak Mountains in central-eastern Korea, the Sinmu-mun samples yielded the cutting dates A.D. 1868, 1869, and 1870/1871. Surprisingly, these dates are 3 to 6 year later than the known date (A.D. 1865) of the Sinmu-mun reconstruction, which was recorded in a historical document ‘Ilsungrok’, the King’s official diary. Since the time that the Sinmu-mun construction date had been questioned, another record was found in the 1872 April issue of Ilsungrok, indicating the rebuilding of Sinmu-mun in the 1870s. Both pieces of evidence, from tree-ring dates and historic records, prove that the rebuilding of Sinmu-mun started after the Fall of 1870, but not later than April 1872. The results prove that tree-ring dating is a precise dating method and it can be applied to archaeological studies on Korean structures.
    • Tree-Ring-Derived Precipitation Records From Inner Mongolia, China, Since A.D. 1627

      Liu, Yu; Sun, Junyan; Yang, Yinke; Cai, Qiufang; Song, Huiming; Shi, Jiangfeng; An, Zhisheng; Li, Xuxiang; The State Key Laboratory of Loess and Quaternary Geology, The Institute of Earth Environment, Chinese Academy of Sciences Xi’an 710075, China; Department of Environment Engineering, School of Energy and Power Engineering of Xi’an Jiaotong University; et al. (Tree-Ring Society, 2007-06)
      Two Chinese pine (Pinus tabulaeformis) tree-ring width chronologies up to 375 years long were used to reconstruct rainfall from February to early July for the Wu Dangzhao region and from February to mid-July for the La Madong region, Inner Mongolia, China. The predictor variables account for 44.3% and 42.7% of the variance in precipitation, respectively. Both historical records and two other tree-ring based precipitation reconstructions from the environmentally sensitive zone (the northern Helan Mountain range and Baiyinaobao) confirm our results. After applying a 10-year moving average, the trends of four tree-ring based precipitation reconstructions vary synchronously. Periods with below-normal precipitation occurred during the 1720s–1730s, 1740s–1750s, 1790s, early 1810s, late 1830s–1860s, 1880s–1910s, late 1920s–1930s and after the late 1960s–early 1970s. Periods with above-normal precipitation occurred in the 1760s to early 1770s, 1820s to early 1830s, 1870s–1880s, early 1920s, 1940s to early 1960s, and 1990s. The late 1920s period was the most severe drought over a broad area in north China in the last 375 years. In contrast, the wettest period was in the late 1990s.