Document Type
Article
Language
eng
Publication Date
11-8-2015
Publisher
The Royal Society
Source Publication
Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences
Source ISSN
1471-2946
Abstract
Stream runoff is perhaps the most poorly represented process in ecohydrological stochastic soil moisture models. Here we present a rainfall-runoff model with a new stochastic description of runoff linked to soil moisture dynamics. We describe the rainfall-runoff system as the joint probability density function (PDF) of rainfall, soil moisture and runoff forced by random, instantaneous jumps of rainfall. We develop a master equation for the soil moisture PDF that accounts explicitly for a general state-dependent rainfall-runoff transformation. This framework is then used to derive the joint rainfall-runoff and soil moisture-runoff PDFs. Runoff is initiated by a soil moisture threshold and a linear progressive partitioning of rainfall based on the soil moisture status. We explore the dependence of the PDFs on the rainfall occurrence PDF (homogeneous or state-dependent Poisson process) and the rainfall magnitude PDF (exponential or mixed-exponential distribution). We calibrate the model to 63 years of rainfall and runoff data from the Upper Little Tennessee watershed (USA) and show how the new model can reproduce the measured runoff PDF.
Recommended Citation
Bartlett, Mark; Daly, E.; McDonnell, Jeffrey; Parolari, Anthony J.; and Porporato, Amilcare, "Stochastic Rainfall-runoff Model with Explicit Soil Moisture Dynamics" (2015). Civil and Environmental Engineering Faculty Research and Publications. 188.
https://epublications.marquette.edu/civengin_fac/188
Comments
Accepted version. Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, Vol. 471, No. 2183 (November 8, 2015). DOI. © 2015 The Royal Society. Used with permission.