摘要
利用中国气象局国家气候中心740站点1960—2000年日降水观测资料,研究日降水幂律尾指数随时间的演变特征,结果表明中国华北、东北和西北地区0—7mm日降水幂律尾指数在1979—1980年之间发生突变,由此推测中国北方地区的大尺度气候背景在上世纪70年代末80年代初曾出现较大变化.该突变与厄尔尼诺和南方涛动(ENSO)综合指数联系紧密,可能是造成北方干旱化的重要原因之一.进一步分析表明,0—29mm日降水过程平稳性较好,30mm以上日降水过程平稳性相对较差,使得长期的暴雨预测面临严峻的挑战.
Based on the daily precipitation observations of 740 stations in China from 1960 to 2000, the abrupt change point of powerlaw exponents of daily precipitation of 0--7 mm in north China, northeast China and northwest China is located exactly on 1979. This indicates that the large-scale climate background of these regions has changed at that time, and it has close relation with the index MEI. This maybe one of the main reasons for the drying trend of north China. The 0--29 mm daily precipitation is to some extent a stationary process, and the daily precipitation being ≥30 mm is obviously non-stationary, which makes the long-term prediction of heavy rainfall very difficult.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2008年第7期4629-4633,共5页
Acta Physica Sinica
基金
国家自然科学基金(批准号:40675044)
国家重点基础研究发展计划(973)项目(批准号:2004CB418300)资助的课题~~
关键词
幂律尾指数
突变
北方干旱化
暴雨
power-law exponent, abrupt change, drying trend of north China, heavy rainfall
