摘要
利用中国614个气象台站1951—2006年历年月平均降水资料,计算各站的标准化降水指数及其干旱等级序列,采用REOF等方法进行气候分区,分析各区域近55a干旱等级的时空变化,并着重讨论了黄淮—华北冬小麦种植区冬季干旱的大气环流特征。结果表明,我国冬季降水具有显著的年代际变化,西北的新疆地区,华北及黄淮地区自进入21世纪以来,冬季降水量增加十分明显,而西南,青藏高原及华南地区冬季降水量有所减少。根据标准化降水指数的旋转载荷向量可将中国划分为13个区域,其干旱等级序列和代表站资料反映出近55a西北地区东部、河套及华北北部有变干的趋势,而新疆北部、东北北部、华北南部、江淮、江南地区降水量有增加的趋势。乌拉尔山—青藏高原脊、东亚大槽及西太平洋副高是影响北方冬麦区旱涝最主要的大气环流系统,其对分析、预测旱涝具有十分重要的指示意义。
The standardized precipitation index （SPI） was calculated by using the winter monthly mean precipitation data during the period of 1951 2006 from 614 meteorological stations in China and then the drought degree was assessed in the paper. Winter aridity division was made by using REOF method, and the temporal and spatial variation of drought degree in each region was analyzed, then the atmospheric circulation characteristics was analyzed in view of the winter drought in northern winter wheat areas. The results show that there was obvious interdecadal variability in winter precipitation in China, and the precipitation in winter increased obviously in Xinjiang, Huabei area and Huanghuai area since 2000s, while the precipitation in winter decreased in Southwest area, Huanan area and Tibetan Plateau. The primary thirteen rotated loading vector fields of SPI represented thirteen winter aridity regions. The analysis results showed that winter precipitation had decreased obviously in east Northwest area, Hetao area and north Huabei, and it had increased in north Xinjiang area, north Northeast area, south Huabei, Jianghuai area and Jiangnan area in the recent 55 years. Ural-Tibetan Plateau ridge, East Asia trough and the Pacific subtropical high were the most important atmospheric circulation to affect the degree of drought and flood in northern winter wheat areas.
出处
《中国沙漠》
CSCD
北大核心
2010年第4期917-925,共9页
Journal of Desert Research
基金
科技部科研院所社会公益研究项目(2004DIB5J192)资助
关键词
气候分区
标准化降水指数
干旱等级
环流特征
climate division
standardized precipitation index（SPI）
drought degree
circulation characteristics
