The hierarchy and definition of the precipitation-concentration degree and precipitation- concentration period of annual precipitation have been proposed by using the so-called vector method of annual distribution of ...The hierarchy and definition of the precipitation-concentration degree and precipitation- concentration period of annual precipitation have been proposed by using the so-called vector method of annual distribution of precipitation,so that the two relevant parameters can represent the annual distribution of total precipitation correctly and indeed accurately.The relationship between the spatial and temporal distribution patterns and variations of the two parameters and the annual precipitation amount in China has been further investigated.Results demonstrate that the precipitation-concentration degree and the precipitation-concentration period increase from southeast to northwest gradually.Moreover there obviously exists a belt pattern:the largest variability of the precipitation-concentration degree and the precipitation-concentration period occurs in the Yellow River Valley and the middle and lower reaches of the Yangtze River, corresponding to the significant zones in which flood and drought take place frequently.It is found that there exist high correlations between the precipitation-concentration degree and precipitation- concentration period and the annual precipitation amount in Northeast China,North China,the middle and lower reaches of the Yangtze River. Furthermore,8-year and 22-year periodic oscillations in the precipitation-concentration degree and 6-year and 12-year cycles in the precipitation-concentration period are identified by use of their Morlet wavelet analysis.展开更多
Based on 740 stations of daily precipitation datasets in China, the precipitationconcentration degree （PCD） and precipitation-concentration period （PCP） of different intensity durative precipitation events were ca...Based on 740 stations of daily precipitation datasets in China, the precipitationconcentration degree （PCD） and precipitation-concentration period （PCP） of different intensity durative precipitation events were calculated to analyze their statistical characteristics, mainly including spatial and temporal distributions, variations and climatic trends of the two parameters of the durative heavy precipitation events in China. It is proved that these two parameters of heavy rainfall can display the temporal inhomogeneity in the precipitation field. And it is also found that there is a good positive relationship between the precipitation-concentration degree and annual rainfall amount in the Eastern and Central China. This method can be anolied in flood assessment and climate change fields.展开更多
基金the National Natural Science Foundation of China projects"Studies on interaction between the South Asia high and the Asian monsoon and its mechanisms"(40175021)"Interannual and interdecadal variations of Meiyu in the Yangtze-Huaihe River Basins and their mechanisms"(40233037)
文摘The hierarchy and definition of the precipitation-concentration degree and precipitation- concentration period of annual precipitation have been proposed by using the so-called vector method of annual distribution of precipitation,so that the two relevant parameters can represent the annual distribution of total precipitation correctly and indeed accurately.The relationship between the spatial and temporal distribution patterns and variations of the two parameters and the annual precipitation amount in China has been further investigated.Results demonstrate that the precipitation-concentration degree and the precipitation-concentration period increase from southeast to northwest gradually.Moreover there obviously exists a belt pattern:the largest variability of the precipitation-concentration degree and the precipitation-concentration period occurs in the Yellow River Valley and the middle and lower reaches of the Yangtze River, corresponding to the significant zones in which flood and drought take place frequently.It is found that there exist high correlations between the precipitation-concentration degree and precipitation- concentration period and the annual precipitation amount in Northeast China,North China,the middle and lower reaches of the Yangtze River. Furthermore,8-year and 22-year periodic oscillations in the precipitation-concentration degree and 6-year and 12-year cycles in the precipitation-concentration period are identified by use of their Morlet wavelet analysis.
基金Concentrated fund item of nationalscience and technology foundation work,No.2001DEA30029-0604Jiangsunaturalsciencefoundation,No.BK2005163
文摘Based on 740 stations of daily precipitation datasets in China, the precipitationconcentration degree （PCD） and precipitation-concentration period （PCP） of different intensity durative precipitation events were calculated to analyze their statistical characteristics, mainly including spatial and temporal distributions, variations and climatic trends of the two parameters of the durative heavy precipitation events in China. It is proved that these two parameters of heavy rainfall can display the temporal inhomogeneity in the precipitation field. And it is also found that there is a good positive relationship between the precipitation-concentration degree and annual rainfall amount in the Eastern and Central China. This method can be anolied in flood assessment and climate change fields.
