Abstract: | The stochastic–conceptual rainfall–runoff simulator (SCRRS) developed by R. A. Freeze in 1980 was used in this study to demonstrate quantitatively the interplay of the factors that control the occurrence of overland flow by the Horton and Dunne mechanisms. The simulation domain and input data for the SCRRS simulations reported here were abstracted from the R‐5 catchment (Chickasha, OK) data sets. The results illustrate that the identification of a dominant hydrological response process may not be as simple as a singular Horton or Dunne characterization. The SCRRS simulations show that the Horton and Dunne processes can (i) occur simultaneously at different locations during a given rainfall event, (ii) change from one process to the other with time depending on the characteristics of the rainfall event, and (iii) be strongly dependent on the initial conditions. Copyright © 2001 John Wiley & Sons, Ltd. |