摘要
Estimation of the annual runoff frequency distribution is an essential basis for water resource management.This study proposes a framework for estimating the annual runoff frequency distribution across252 catchments in China based on climatic conditions and catchment characteristics from 1956 to 2000.The Budyko land-specific parameter n,which intergrates influences other than the mean climate conditions,is firstly estimated based on easily ascertainable catchment characteristics without the requirementsof having long-term runoff observations.Second,the annual runoff statistical parameters,namely,the mean value and standard deviation(STD),are derived based on the Budyko rainfall-runoffmodel with the central moment method.Finally,the annual runoff on any recurrence interval is obtainedby the Pearson-Ill frequency function.Results show that the parameter n can be estimated fromthe catchment average slope,longitude,and climatic seasonality index.The estimated statistical parametersof annual runoff have acceptable agreement with observed values(mean value:R^(2)-0.94,STD:R^(2)-0.91,and both relative errors<10%).In addition,estimated annual runoff at each catchment fortypical wet and dry years(25%and 75%ranked percentiles)coincides well with observed values,with R^(2) of 0.92-0.93 and relative erors less than 10%.This result indicates the robustness of this framework forestimating the annual runoff frequency distribution,which provides a simple and effective tool forungauged orpoorlygauged catchments.
基金
Map(Fig.1)in this article was reviewed by the Beijing Municipal Commission of Planning and Natural Resources[No.GSJING(2023)0928]
This research was supported by funding from the National Natural Science Foundation of China(Grant Nos.51979140 and 51622903)
the National Program for Support of Top-notch Young Professionals.
