Spatiotemporal characteristics of rainfall process in a small mountainous catchment  

作　　者：CHENG Jianyi GUO Xiaojun LI Yong LIU Daochuan LIU Jihong 

机构地区：[1]Key Laboratory of Mountain Hazards and Surface Process/Institute of Mountain Hazards and Environment,Chinese Academy of Sciences,Chengdu 610041,China [2]University of Chinese Academy of Sciences,Beijing 100081,China [3]Sichuan Highway Planning,Survey,Design and Research Institute Ltd.,Chengdu 610041,China [4]State Key Laboratory of Subtropical Silviculture,Zhejiang A&F University,Hangzhou 311300,China

出　　处：《Journal of Mountain Science》2024年第12期4033-4049,共17页山地科学学报（英文）

基　　金：supported by the Second Scientific Expedition on the Qinghai-Tibet Plateau(2019QZKK0903-02);NSFC(42322703 and U21A2008);Sichuan S&T project(2022JDJQ0008);Western Light of Young Scholars,CAS.

摘　　要：The spatial distribution and temporal process of rainfall are major problems in small mountainous catchments.This study investigated the spatiotemporal characteristics of rainfalls using data obtained from a dense monitoring network(10 gauges)in a small catchment of 48.6 km2.The rainfall process is determined by empirical relations(rainfall-elevation and rainfall-duration relations)with a random fluctuation.The rainfall-elevation relation of event-scale is R=21.7h+4.6,the rainfall-area relations are suggested as a Gaussian distribution,and the rainfall-duration relation is a power law function.The process was investigated at 1-min resolution and characterized by index including the onset time,duration,and center time of the rainfall peak period.Analysis revealed that the errors were random and followed a normal distribution.Consequently,a method that incorporates the relations of rainfall amount and the stochastic errors is proposed to simulate the rainfall process.Comparing with the monitored data,both the errors of simulated rainfall amount and peak intensity were in the range of[−30%,30%].Additionally,the relations of the simulated and monitored rainfall amount/intensity with the area are both very close.This study marks an attempt to establish a framework for simulation of rainfall at a high temporal resolution(1-min)which is significant to the hydrological hazards forecasting,and realizing the spatial distribution of rainfall within a small catchment.

关 键 词：RAINFALL Spatial distribution Temporal process Stochastic simulation 

分 类 号：P426.6[天文地球—大气科学及气象学] P333[天文地球—水文科学]