摘要
基于历史文献中的旱涝灾害记录,采用5级制划分的旱涝灾害等级,使用系统聚类法将中国西北地区19个站点划分为7个分区,利用湿润指数公式重建了西北地区7个分区1470—2008年的年分辨率干湿变化序列,比较分析了各分区干湿气候变化的阶段特征、周期性及跃变现象。结果表明：重建序列信度较高,可用作气候干湿变化研究。西北地区7个分区1470—2008年干湿变化存在着11a、25~35a和80~100a的3类周期变化。其中,11a和25~35a的两个周期变化在整个分析时间段内表现得较为稳定;80~100a的周期变化则表现的较不稳定。世纪尺度和气候代尺度的跃变信号各区皆有出现,位于研究区两边的陕西和玉树地区出现最少,宁夏和格尔木地区次之;位置居中的兰州、张掖、西宁等地区跃变信号出现最多,是气候干湿变化的敏感地带。检测出的干湿跃变信号主要集中在17世纪前后,近百年气候干湿变化则相对稳定。
Based on the historical record,dry/wet series since 1470-2008 AD in Northwest China were reconstructed and analyzed.The dry/wet series for 7 regions are expressed by five grades,and dry/wet climate is obtained from a cluster analysis on annual data during 1470-2008 at 19 stations in Northwest China.The variation feature of the dry/wet series,such as phase characteristics,periodicity and abrupt change,are presented.The results show that the reconstruction of sequence reliability is high,and it can be used as a dry/wet climate change research.Wavelet analysis shows that those periodicities existed in the last 500 years,such as the periods of around 11 year,25-35 year,80-100 year.Among them,11 years and 35 years periodicities in the whole analysis period are relatively stable than80-100 years periodicities.The signs of abrupt changes in the 7 regional dry/wet series were detected by moving t-test.It is indicated that abrupt climatic changes have occurred for every regions in Northwest China during 1470-2008 AD.Both edge of the study area,such as Shaanxi and Yushu,abrupt signal appears fewest times;Ningxia and Golmud is second;the signal appears most times in the middle study area such as Lanzhou,Zhang ye,Xining.It means middle area is the sensitive area of dry/wet climate change.The dry/wet abrupt signal mainly concentrated in the 17 th century,dry/wet climate change in recent century is relatively stable.
出处
《中国沙漠》
CSCD
北大核心
2016年第5期1278-1285,共8页
Journal of Desert Research
基金
中国科学院重点部署项目(KJZD-EW-G0304)
中国科学院国家外国专家局创新团队国际合作伙伴计划项目
冰冻圈科学国家重点实验室自主课题(SKKLCS-ZZ-2016)
国家自然科学基金创新研究群体项目(41421061)
国家社会科学基金面上项目(14BGL137)
关键词
干湿气候
气候重建
周期
突变
西北地区
dry/wet climate
climate reconstruction
periodicities
abrupt change
Northwest China
