Author(s)

G. Tanaka, M. Fujita, S. Kumagai, Y. Sakai & L. Hamouda

Abstract

It is well known that the rainfall runoff phenomenon is more or less stochastic. If the runoff system is linear, it is easy to estimate the stochastic response by using, for example, the spectrum theory. However, the rainfall runoff phenomenon is a nonstationary random process. Thus, the spectrum theory cannot provide sufficient solutions to describe the stochastic property of the runoff system. In this paper, we adopt the Kinematic Wave model and the storage function runoff model derived from the Kinematic Wave model as the runoff system, and we propose differential equations whose solutions provide a variance of discharge even if the runoff system is nonlinear.

Keywords