The geomorphologic structure of hydrologic response

TLDR

The instantaneous unit hydrograph (IUH) varies over time within a storm and between storms. The study aims to unify catchment hydrologic response by linking the IUH with geomorphologic basin parameters and to initiate an approach to hydrologic similarity. Equations relate the IUH to Horton's numbers, an internal scale parameter, and mean streamflow velocity, accounting for its variability. The model shows that geomorphologic structure unifies diverse hydrologic responses observed in nature.

Abstract

A unifying synthesis of the hydrologic response of a catchment to surface runoff is attempted by linking the instantaneous unit hydrograph (IUH) with the geomorphologic parameters of a basin. Equations of general character are derived which express the IUH as a function of Horton's numbers R A , R B , and R L ; an internal scale parameter L Ω and a mean velocity of streamflow v . The IUH is time varying in character both throughout the storm and for different storms. This variability is accounted for by the variability in the mean streamflow velocity. The underlying unity in the nature of the geomorphologic structure is thus carried over to the great variety of hydrologic responses that occur in nature. An approach is initiated to the problem of hydrologic similarity.