STABILITY AND POTENTIAL PREDICTABILITY OF ANNUAL PERCIPITATION OVER CHINA

The precipitation is a primary element which directly affects the agricultural production of the country with one fifth of the world population.With the economic development the water resource stress is getting greater.In this paper,based on the data at 162 stations selected evenly over China from 1960 to 1991 the stability and potential predictability of annual precipitation have been studied.The eastern and southern parts of the country having abundant precipitation enjoy more stable precipitation.The north and northwest parts of the country where the precipitations are deficient have unstable precipitations.The potential predictability approximates to the ratio of the estimated interannual variance to the climatic noise.Generally the annual precipitation over China is potentially predictable.In the area between the Huanghe River and Changjiang River and the east of northeastern China the potential predictability is the lowest in the country.In the north and northwest of the country the potential predictability is greater.The southeastern coast has relatively low values of potential predictability.Also,the method of estimating climatic noise of annual precipitation has been discussed from the idea of Yamamoto et al.(1985) in order to estimate the potential predictability.