过去千年西北季风边缘区干湿变化的重建及分析  

The reconstruction of dry and wet variation in monsoon boundary zone of northwest China by records of historical documents over the past millennium

作　　者：杨煜达[1] 韩健夫 成赛男[1] 

机构地区：[1]复旦大学中国历史地理研究所,上海200433

出　　处：《地球环境学报》2014年第6期392-399,共8页Journal of Earth Environment

基　　金：教育部全国优秀博士学位论文作者专项资金资助项目(201114)

摘　　要：利用历史文献中的旱涝灾害记载，成功建立了西北季风边缘区AD1000-1949的逐年湿润指数，能比较好地指代这一区域的干湿变化情况。在过去千年中，西北季风边缘区有一次大的由干变湿的转折，发生在AD1550后。同时存在较明显的60-70a周期和110a左右的周期。通过与树轮重建的非季风区的干湿变化及与石笋重建的夏季风强弱变化相比较，发现季风边缘区的干湿变化和季风系统的活动密切相关。暖期时，季风边界推进，传统的季风边缘区将变干燥。当偏冷时期，夏季风保持稳定，季风边缘区湿润。当季风明显减弱时，季风边界两侧的边缘区和非季风区则因夏季风边界的退缩而同时变干。This paper reconstructs humidity index series of CNWMBZ （northwest China monsoon boundary zone） from 1000 to 1949 AD. by Chinese historical documents, to analyze the dry/wet variation of the study area. The reconstruction result shows a turning point at around 1550 AD. Before 1550 AD, the climate of CNWMBZ is generally dry, while the climate shifts to wet after 1550 AD. There are also inter-centennial fluctuations of dry and wet phases during the last millennium. The wavelet analysis on the humidity index of CNWMBZ exhibits periodicity at 60-70-year and 110-year. Comparisons with the dry/wet variation of the non-monsoon region reconstructed by tree ring and with the summer monsoon intensity rebuilt by cave records demonstrate that, the dry/wet variation of CNWMBZ is closely related with the monsoon system. During the warm period, the monsoon region boundary moves forward, the study area （i.e. the CNWMBZ） exhibits dry tendency; during the comparatively cold period, the summer monsoon is relatively strong, the monsoon boundary is generally stable, the study area is comparatively wet; during the very cold period, the summer monsoon is very weak, the monsoon boundary retreats, the study area and the non-monsoon region both show dry tendency.

关 键 词：夏季风 季风边缘区 干湿变化 千年尺度 历史文献 中国西北 

分 类 号：P467[天文地球—大气科学及气象学]