HR: 09:15h
AN: H11G-05    [Abstracts]
TI: Use of Residence Time and Hydrograph Component Information to Test Effective Parameters in a Physically Based Rainfall-Runoff Model
AU: * Sayama, T
EM: sayama@flood.dpri.kyoto-u.ac.jp
AF: Department of Forest Engineering, Oregon State University, 015 Peavy Hall, Corvallis, OR 97331, United States
AU: * Sayama, T
EM: sayama@flood.dpri.kyoto-u.ac.jp
AF: Disaster Prevention Research Institute, Kyoto University, Gokasho, Uji, Kyoto, 6110011, Japan
AU: McDonnell, J J
EM: jeff.mcdonnell@oregonstate.edu
AF: Department of Forest Engineering, Oregon State University, 015 Peavy Hall, Corvallis, OR 97331, United States
AU: Tachikawa, Y
EM: tachikawa@mbox.kudpc.kyoto-u.ac.jp
AF: Department of Urban and Environmental Engineering, Kyoto University, Nishikyo-ku, Kyoto, 6158540, Japan
AU: Takara, K
EM: takara@flood.dpri.kyoto-u.ac.jp
AF: Disaster Prevention Research Institute, Kyoto University, Gokasho, Uji, Kyoto, 6110011, Japan
AB: Many rainfall-runoff models exist that can reproduce the behavior of storm hydrographs. As these models become the basis for landuse and climate change prediction, it becomes essential that they work for the right process reasons. Much ambiguity still exists in how model parameters relate to field measurements and how model structure capture dominant runoff processes. Recent work has demonstrated that stream water mean residence time and storm hydrograph components provide measures of watershed behavior that are orthogonal and non- redundant to the stream hydrograph. However, to date, only conceptual models have been tested in this way. This paper reports on an analysis of a distributed physically based model to represent watershed behavior. We ask the questions: Can effective parameters calibrated from large river basins be used to reproduce small scale watershed behavior in terms of reproducing stream flow hydrograph, residence time and source components? And what level of detail is warranted in the model to represent these components? We used a distributed rainfall-runoff model applied to a small catchment (Maimai catchment, New Zealand, 3.7 ha) and field observed data including stream flow, isotopic / geochemical tracers. We first investigated whether field measured soil properties can be used directly as a model parameter to reproduce reasonable hydrographs at the outlet. We then applied effective parameter sets calibrated from a large river basin to see how the parameter sets could be used at the smaller scale. Finally, we examined the ability to reproduce mean residence time and new/old water component with parameters obtained from soil property and calibrated from the large river basin to assess the model can represent the watershed behavior.
DE: 1835 Hydrogeophysics
DE: 1846 Model calibration (3333)
DE: 1847 Modeling
DE: 1860 Streamflow
DE: 1879 Watershed
SC: Hydrology [H]
MN: 2007 Fall Meeting