HR: 08:05h
AN: H21I-01 INVITED     [Abstracts]
TI: Physics-based hydrologic-response simulation: A quantitative foundation for hydroecology and hydrogeomorphology
AU: * Loague, K
EM: keith@pangea.stanford.edu
AF: Department of Geological and Environmental Sciences, Stanford University, Stanford, CA 94305-2115 United States
AU: VanderKwaak, J E
EM: kwaak@pangea.stanford.edu
AF: 3DGeo Development Inc., 4633 Old Ironsides Drive, Suite 401, Santa Clara, CA 95054 United States
AU: Carr, A E
EM: acarr@pangea.stanford.edu
AF: Department of Geological and Environmental Sciences, Stanford University, Stanford, CA 94305-2115 United States
AU: Heppner, C S
EM: hepp@pangea.stanford.edu
AF: Department of Geological and Environmental Sciences, Stanford University, Stanford, CA 94305-2115 United States
AU: Ebel, B A
EM: bebel32@pangea.stanford.edu
AF: Department of Geological and Environmental Sciences, Stanford University, Stanford, CA 94305-2115 United States
AU: Ran, Q
EM: qhran@pangea.stanford.edu
AF: Department of Geological and Environmental Sciences, Stanford University, Stanford, CA 94305-2115 United States
AU: Mirus, B B
EM: bmirus@pangea.stanford.edu
AF: Department of Geological and Environmental Sciences, Stanford University, Stanford, CA 94305-2115 United States
AB: Hundreds of hydrologic-response models have been developed during the last half-century. Each model has its own advantages and shortcomings, with no single model accepted for all applications. More that 35 years ago Freeze and Harlan proposed a blueprint for a distributed physically-based hydrologic model, based upon numerical solution to the coupled partial differential equations that describe water movement on the surface and within the variably-saturated subsurface. It is our contention that the Freeze and Harlan blueprint has not yet been fully tested and therefore deserves continued consideration. For example, physics-based simulation can be a useful tool for concept development, hypothesis testing, dataset evaluation, and developing/testing simpler models. Comprehensive hydrologic-response simulation provides a strong foundation for quantitative hydroecology and hydrogeomorphology. The Integrated Hydrology Model (InHM) is an example of a physics-based hydrologic-response model that was developed in the spirit of the Freeze and Harlan blueprint. InHM has been designed to quantitatively estimate, in a fully-coupled approach, 3D variably-saturated flow and solute transport in porous media, 3D variably-saturated flow and solute transport in macropores, and 2D flow and solute/sediment transport over the land surface and in open channels. InHM's first-order coupling facilitates detailed examination of interactions that are not obvious, thereby advancing our understanding of the non-intuitive interplay between processes that are not mutually exclusive. Results from several ongoing InHM applications are presented for simulation efforts focused on rangeland/forest hydrology, cumulative watershed effects, sediment transport, slope stability, and regional-scale landscape evolution. Important issues addressed include steady-state versus transient simulation, 1D/2D versus 3D boundary-value problem characterization, event-based versus continuous simulation, spatio-temporal variability of near-surface soil-hydraulic properties, and some of the problems inherent to the rigorous assessment of model performance.
DE: 1810 Debris flow and landslides
DE: 1815 Erosion
DE: 1830 Groundwater/surface water interaction
DE: 1847 Modeling
DE: 1875 Vadose zone
SC: Hydrology [H]
MN: Fall Meeting 2005