摘要
In this paper, a new index of drought and wet is presented, which characterizes demand of water in some places and reflects the contribution of prephase precipitation to recent drought. This paper discusses the change of drought and wet in North China in recent several decades. It is discovered that the drought trend in North China is the most obvious. Seasonal character and periodical change of drought trend in North China are investigated and some useful conclousions are draw. Finally, the paper discusses successive drought phenomenon in North China in recent years and points out that the successive drought occurred in recent two years is the most serious in recent half century, and it will be concerned about.
In this paper, a new index of drought and wet is presented, which characterizes demand of water in some places and reflects the contribution of prephase precipitation to recent drought. This paper discusses the change of drought and wet in North China in recent several decades. It is discovered that the drought trend in North China is the most obvious. Seasonal character and periodical change of drought trend in North China are investigated and some useful conclousions are draw. Finally, the paper discusses successive drought phenomenon in North China in recent years and points out that the successive drought occurred in recent two years is the most serious in recent half century, and it will be concerned about.
