摘要
利用白银市4站1957-2000年44年的降水资料,计算了"四旱"干旱指数,分析了各旱段干旱的气候特征。结果表明:全市每年都有干旱发生,即每年至少有一站发生某一干旱。在4个旱段中,春旱频率最高,春末夏初旱次之,干旱频率从南至北增加;全市90%的年份降水偏差一致,但南部的降水比北部多一倍且稳定性较好。另外初步分析了"四旱"的形成原因。
the precipitation data between 1957 and 2000 in Baiyin are analyzed, the dry indices of the '4 periods' are calculated and the climatic features of these dry periods are studied. The results show that at least one drought happens over the Baiyin region every year with the spring drought of the highest frequency and that in late spring and early summer of the second highest frequency. The drought frequency in the south is higher than that in the north and 90% annual precipitation deviation is consistent with the south quantity double that of the north and better stability. The cause of the formation of the '4 droughts' is also analyzed.
出处
《成都信息工程学院学报》
2003年第1期49-54,共6页
Journal of Chengdu University of Information Technology
