VARIATIONS OF DRYNESS AND WETNESS IN CHINA DURING 1951 - 1980
近30年来中国气候的干湿变化

In this paper, the potential evapbtranspiration is calculated by using the Thornthwaite 's (1948) system and the moisture index is determined by comparison of it with the corresponding precipitation at 340 stations in China, based on the monthly mean temperature and precipitation data sets of the years 1951 - 1980.According to the analysis of the moisture indices, the climatic regions in China are classified into five types. The secular variations of the dryness and the wetness in each climatic region during the period of 1951 - 1984 are discussed.It is revealed that the trend of precipitation in North China was similar to that in the Sahel to some extent during the last 20 years, but the drought in North China was not as severe as that in the Sahel.