A coupled ModClark-curve number rainfall-runon-runoff model

作者:Saghafian B*; Noroozpour S; Kiani M; Nasab A Rafieei
来源:Arabian Journal of Geosciences, 2016, 9(4): 277.
DOI:10.1007/s12517-015-2295-4

摘要

Understanding of major processes in rainfall-runoff transformation is of great importance to hydrologists. Various phenomena interact to form a hydrograph; one that is often neglected is known as runon. Runon is a part of runoff that has no chance to infiltrate upstream due to high precipitation intensity or low soil permeability, while it infiltrates downstream. Runon has not been considered in common hydrologic studies, mainly due to inadequate while applied formulation. In this paper, a novel rainfall-runon-runoff mathematical model is developed via Soil Conservation Service (SCS) infiltration and ModClark rainfall-runoff coupled models. After deriving model formulation, three different spatial patterns of curve number (uniform, downstream increasing, and decreasing) in conjunction with various rainfall durations and intensities were investigated under with and without runon scenarios over a V-shaped watershed. The results indicated that there was lower surface runoff volume and peak discharge in all cases when runon was accounted for. In particular, in regions with low curve number, there were major differences between the hydrographs simulated by the commonly practiced norunon model and the presented runon model. Moreover, the runon effect in case of decreasing curve number in downstream direction was more pronounced than that of the increasing case. However, this effect decreased with depth, intensity, and duration of rainfall.

  • 出版日期2016-4