Estimating daily flow duration curves from monthly streamflow data

Abstract

The paper describes two techniques by which to establish 1-day (1d) flow duration curves at an ungauged site where only a simulated or calculated monthly flow time series is available. Both methods employ the straightforward relationships between daily and monthly flow characteristics. These relationships are first established on the basis of observed stream flow data and then used to convert synthetic monthly flow data into 1 d flow duration curves. The paper suggests the conversion equations and describes step-by-step calculation procedures which may be applied to generate 1 d flow duration curves at quaternary catchment level of spatial resolution.