Joseph Hughes (Former Employee)
Science and Products
Filter Total Items: 45
MODFLOW-based coupled surface water routing and groundwater-flow simulation MODFLOW-based coupled surface water routing and groundwater-flow simulation
In this paper, we present a flexible approach for simulating one- and two-dimensional routing of surface water using a numerical surface water routing (SWR) code implicitly coupled to the groundwater-flow process in MODFLOW. Surface water routing in SWR can be simulated using a diffusive-wave approximation of the Saint-Venant equations and/or a simplified level-pool approach. SWR can...
Authors
Joseph D. Hughes, Christian D. Langevin, Jeremy T. White
Utilizing dimensional analysis with observed data to determine the significance of hydrodynamic solutions in coastal hydrology Utilizing dimensional analysis with observed data to determine the significance of hydrodynamic solutions in coastal hydrology
In this paper, the authors present an analysis of the magnitude of the temporal and spatial acceleration (inertial) terms in the surface-water flow equations and determine the conditions under which these inertial terms have sufficient magnitude to be required in the computations. Data from two South Florida field sites are examined and the relative magnitudes of temporal acceleration...
Authors
Eric D. Swain, Jeremy D. Decker, Joseph D. Hughes
Quantifying the predictive consequences of model error with linear subspace analysis Quantifying the predictive consequences of model error with linear subspace analysis
All computer models are simplified and imperfect simulators of complex natural systems. The discrepancy arising from simplification induces bias in model predictions, which may be amplified by the process of model calibration. This paper presents a new method to identify and quantify the predictive consequences of calibrating a simplified computer model. The method is based on linear...
Authors
Jeremy T. White, John E. Doherty, Joseph D. Hughes
Feedback of land subsidence on the movement and conjunctive use of water resources Feedback of land subsidence on the movement and conjunctive use of water resources
The dependency of surface- or groundwater flows and aquifer hydraulic properties on dewatering-induced layer deformation is not available in the USGS's groundwater model MODFLOW. A new integrated hydrologic model, MODFLOW-OWHM, formulates this dependency by coupling mesh deformation with aquifer transmissivity and storage and by linking land subsidence/uplift with deformation-dependent...
Authors
Wolfgang Schmid, Randall T. Hanson, Stanley A. Leake, Joseph D. Hughes, Richard G. Niswonger
Documentation of the seawater intrusion (SWI2) package for MODFLOW Documentation of the seawater intrusion (SWI2) package for MODFLOW
The SWI2 Package is the latest release of the Seawater Intrusion (SWI) Package for MODFLOW. The SWI2 Package allows three-dimensional vertically integrated variable-density groundwater flow and seawater intrusion in coastal multiaquifer systems to be simulated using MODFLOW-2005. Vertically integrated variable-density groundwater flow is based on the Dupuit approximation in which an...
Authors
Mark Bakker, Frans Schaars, Joseph D. Hughes, Christian D. Langevin, Alyssa M. Dausman
Use of general purpose graphics processing units with MODFLOW Use of general purpose graphics processing units with MODFLOW
To evaluate the use of general-purpose graphics processing units (GPGPUs) to improve the performance of MODFLOW, an unstructured preconditioned conjugate gradient (UPCG) solver has been developed. The UPCG solver uses a compressed sparse row storage scheme and includes Jacobi, zero fill-in incomplete, and modified-incomplete lower-upper (LU) factorization, and generalized least-squares...
Authors
Joseph D. Hughes, Jeremy T. White
Non-USGS Publications**
Nyer, E., Mayfield, P., and Hughes, J.D, 1998. Beyond the AFCEE Protocol for Natural Attenuation: Ground Water Monitoring and Remediation, v. 18, no. 3, 70-77.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Filter Total Items: 45
MODFLOW-based coupled surface water routing and groundwater-flow simulation MODFLOW-based coupled surface water routing and groundwater-flow simulation
In this paper, we present a flexible approach for simulating one- and two-dimensional routing of surface water using a numerical surface water routing (SWR) code implicitly coupled to the groundwater-flow process in MODFLOW. Surface water routing in SWR can be simulated using a diffusive-wave approximation of the Saint-Venant equations and/or a simplified level-pool approach. SWR can...
Authors
Joseph D. Hughes, Christian D. Langevin, Jeremy T. White
Utilizing dimensional analysis with observed data to determine the significance of hydrodynamic solutions in coastal hydrology Utilizing dimensional analysis with observed data to determine the significance of hydrodynamic solutions in coastal hydrology
In this paper, the authors present an analysis of the magnitude of the temporal and spatial acceleration (inertial) terms in the surface-water flow equations and determine the conditions under which these inertial terms have sufficient magnitude to be required in the computations. Data from two South Florida field sites are examined and the relative magnitudes of temporal acceleration...
Authors
Eric D. Swain, Jeremy D. Decker, Joseph D. Hughes
Quantifying the predictive consequences of model error with linear subspace analysis Quantifying the predictive consequences of model error with linear subspace analysis
All computer models are simplified and imperfect simulators of complex natural systems. The discrepancy arising from simplification induces bias in model predictions, which may be amplified by the process of model calibration. This paper presents a new method to identify and quantify the predictive consequences of calibrating a simplified computer model. The method is based on linear...
Authors
Jeremy T. White, John E. Doherty, Joseph D. Hughes
Feedback of land subsidence on the movement and conjunctive use of water resources Feedback of land subsidence on the movement and conjunctive use of water resources
The dependency of surface- or groundwater flows and aquifer hydraulic properties on dewatering-induced layer deformation is not available in the USGS's groundwater model MODFLOW. A new integrated hydrologic model, MODFLOW-OWHM, formulates this dependency by coupling mesh deformation with aquifer transmissivity and storage and by linking land subsidence/uplift with deformation-dependent...
Authors
Wolfgang Schmid, Randall T. Hanson, Stanley A. Leake, Joseph D. Hughes, Richard G. Niswonger
Documentation of the seawater intrusion (SWI2) package for MODFLOW Documentation of the seawater intrusion (SWI2) package for MODFLOW
The SWI2 Package is the latest release of the Seawater Intrusion (SWI) Package for MODFLOW. The SWI2 Package allows three-dimensional vertically integrated variable-density groundwater flow and seawater intrusion in coastal multiaquifer systems to be simulated using MODFLOW-2005. Vertically integrated variable-density groundwater flow is based on the Dupuit approximation in which an...
Authors
Mark Bakker, Frans Schaars, Joseph D. Hughes, Christian D. Langevin, Alyssa M. Dausman
Use of general purpose graphics processing units with MODFLOW Use of general purpose graphics processing units with MODFLOW
To evaluate the use of general-purpose graphics processing units (GPGPUs) to improve the performance of MODFLOW, an unstructured preconditioned conjugate gradient (UPCG) solver has been developed. The UPCG solver uses a compressed sparse row storage scheme and includes Jacobi, zero fill-in incomplete, and modified-incomplete lower-upper (LU) factorization, and generalized least-squares...
Authors
Joseph D. Hughes, Jeremy T. White
Non-USGS Publications**
Nyer, E., Mayfield, P., and Hughes, J.D, 1998. Beyond the AFCEE Protocol for Natural Attenuation: Ground Water Monitoring and Remediation, v. 18, no. 3, 70-77.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.