中国昼夜降水特征的空间分异规律  

Spatial and Seasonal Patterns of Diurnal/Nocturnal Precipitation in China

作　　者：苏桐 张文江[1] 覃光华[1] 黎小东[1] 李红霞[1] 兰平 SU Tong;ZHANG Wen-jiang;QIN Guang-hua;LI Xiao-dong;LI Hong-xia;LAN Ping(College of Water Resource and Hydropower,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川大学水利水电学院,四川成都610065

出　　处：《水电能源科学》2024年第4期10-14,共5页Water Resources and Power

基　　金：国家自然科学基金项目(41771112)。

摘　　要：降水昼夜分配的时空特征,是干旱半干旱地区降水资源有效性的重要影响因素。我国昼夜降水空间分异复杂,在雨强、高程、季相等方面的规律还有待进一步研究。为此,采用空间分区、高程分带、雨强分级、季相对比等方法,基于全国839个气象站点1951~2019年的降水资料,研究了我国昼夜降水特征的空间分异规律。结果表明,在空间分区上,我国可划分为受夜间冷却和山谷风效应的青藏及周边夜雨典型区、受辐射对流效应的秦-淮以南昼雨典型区、秦-淮以北降水昼夜相对均衡区;在垂直分异方面,青藏高原及周边山地最为明显,年夜间降水量的高程递减率大于昼间,昼夜差异随海拔升高而减弱;降水的雨强特征为中高雨强降水比重大,尤其是青藏东缘中高强度夜雨显著;季相规律为青藏及西南地区月降水均为夜雨大于昼雨,而南方4~10月昼雨典型。我国昼夜降水特征的空间分异规律,可作为农业与生态水资源气候评估的参考,对山洪预警也有重要意义。Temporal and spatial characteristics of diurnal distribution of precipitation is an important influencing factor for evaluation of the effectiveness of water resources in arid and semi-arid region.As diurnal/nocturnal precipitation is spatially complicated,the attributes of diurnal/nocturnal precipitation related to rain intensity,elevation and season are still not fully understood.In this study,spatial and seasonal patterns of diurnal/nocturnal precipitation were investigated through spatial zoning,elevation banding,rain intensity classifying and seasonal comparison in China with climate records of 1951-2019.The results show that the mainland of China can be subdivided into 3 regions with different characteristics of diurnal/nocturnal precipitation in terms of diurnal/nocturnal proportions,i.e.,the Qingzang and adjacent area with typical nocturnal precipitation,the region on the south of Qinling-Huaihe Line with typical diurnal precipitation,and the rest north region with generally even diurnal/nocturnal precipitation.The decrease in nocturnal precipitation with altitude is larger than diurnal in the Qingzang Plateau,and the nocturnal precipitation is more typical in medium-high precipitation intensity.Seasonally,month nocturnal precipitation is always larger than that of diurnal year around in the Qingzang,while month diurnal precipitation is larger than nocturnal in south China during April to October.These national patterns of diurnal/nocturnal precipitation in China can be referred in assessing the agriculture and ecology water resource climate as well as flash flood warning.

关 键 词：昼夜降水 空间分异 季相变化 雨强规律 海拔效应 年际变化 

分 类 号：TV125[水利工程—水文学及水资源] P426.614[天文地球—大气科学及气象学]