青藏高原南部近千年年代至百年尺度的气候变化研究

过去千年区域尺度气候变化研究，是开展近千年半球、全球尺度气候变化集成重建的基础。本项目拟选择青藏高原南部为研究区域，利用树轮宽度资料，拟在青藏高原南部的不同地区建立RCS和特征值年表序列（在海拔差异大的地区，分海拔高度带建立年表），并开展结合树轮碳氧同位素的测试分析；通过仪器记录对不同方法建立的树轮年表的气候校准和验证，揭示高原南部不同气候类型地区树轮指标对气候要素的响应特点和区域差异，重建高原南部不同气候类型地区近千年来的低频气候变化序列，并对其进行不确定性评估，最终揭示不同地区近千年的气候变化的基本特征，特别是中世纪时期和小冰期气候变化特征（包括幅度、周期和突变）。研究结果将改进区域气候代用记录的空间覆盖度，同时为开展近千年中国与北半球大区域的气候集成研究提供基础数据。

Climate reconstructions on a regional scale is a prerequisite for reconstructing large-scale (hemispheric scale) climate reconstructions for the last millennium. This project intended to choose southern Qinghai-Tibet plateau as research area. Eigen analysis technique will be applied in tree-ring width data to extract low-frequency climatic signal. Together with carbon and oxygen isotopic proxy records, millennium-length tree ring series with low-frequency climatic signals can be established in different parts of the southern Qinghai-Tibet plateau. In some areas, the chronologies will be reconstructed along different elevations. Meanwhile spatial coverage for proxy records can be improved. Finally general characteristics of climate variations on the southern Qinghai-Tibet plateau can be revealed for the past millennium. On the other hand, these results provide basic data for integrated study of climate change for the whole of China and the Northern Hemisphere.