Jeremy White
Dr. Jeremy White is a Supervisory Hydrologic Technician at the Virginia and West Virginia Water Science Center.
He completed his B.S. in computer science at West Texas A&M, and M.S. and Ph.D. in geology at the University of South Florida. Dr. White has extensive experience with parameter estimation and uncertainty quantification in environmental and geophysical models, as well as simulation of surface water and groundwater interactions and density-dependent groundwater flow. Dr. White also has experience using high-performance computing systems to solve massively and embarrassingly parallel problems.
Science and Products
Filter Total Items: 50
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
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
Groundwater quality in West Virginia, 1993-2008 Groundwater quality in West Virginia, 1993-2008
Approximately 42 percent of all West Virginians rely on groundwater for their domestic water supply. However, prior to 2008, the quality of the West Virginia’s groundwater resource was largely unknown. The need for a statewide assessment of groundwater quality prompted the U.S. Geological Survey (USGS), in cooperation with West Virginia Department of Environmental Protection (WVDEP)...
Authors
Douglas B. Chambers, Mark D. Kozar, Jeremy S. White, Katherine S. Paybins
Documentation of the Surface-Water Routing (SWR1) Process for modeling surface-water flow with the U.S. Geological Survey Modular Ground-Water Model (MODFLOW-2005) Documentation of the Surface-Water Routing (SWR1) Process for modeling surface-water flow with the U.S. Geological Survey Modular Ground-Water Model (MODFLOW-2005)
A flexible Surface-Water Routing (SWR1) Process that solves the continuity equation for one-dimensional and two-dimensional surface-water flow routing has been developed for the U.S. Geological Survey three-dimensional groundwater model, MODFLOW-2005. Simple level- and tilted-pool reservoir routing and a diffusive-wave approximation of the Saint-Venant equations have been implemented...
Authors
Joseph D. Hughes, Christian D. Langevin, Kevin L. Chartier, Jeremy T. White
Evaluating the effect of Tikhonov regularization schemes on predictions in a variable-density groundwater model Evaluating the effect of Tikhonov regularization schemes on predictions in a variable-density groundwater model
Calibration of highly‐parameterized numerical models typically requires explicit Tikhonovtype regularization to stabilize the inversion process. This regularization can take the form of a preferred parameter values scheme or preferred relations between parameters, such as the preferred equality scheme. The resulting parameter distributions calibrate the model to a user‐defined acceptable...
Authors
Jeremy T. White, Christian D. Langevin, Joseph D. Hughes
Use of time series and harmonic constituents of tidal propagation to enhance estimation of coastal aquifer heterogeneity Use of time series and harmonic constituents of tidal propagation to enhance estimation of coastal aquifer heterogeneity
A synthetic two‐dimensional model of a horizontally and vertically heterogeneous confined coastal aquifer system, based on the Upper Floridan aquifer in south Florida, USA, subjected to constant recharge and a complex tidal signal was used to generate 15‐minute water‐level data at select locations over a 7‐day simulation period. “Observed” water‐level data were generated by adding noise
Authors
Joseph D. Hughes, Jeremy T. White, Christian D. Langevin
Non-USGS Publications**
White, J.T., Fienen, M.N, and Doherty,J.E. 2016. A python framework for environmental model uncertainty analysis, Environmental Modelling & Software, Volume 85, Pages 217-228, ISSN 1364-8152
**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: 50
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
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
Groundwater quality in West Virginia, 1993-2008 Groundwater quality in West Virginia, 1993-2008
Approximately 42 percent of all West Virginians rely on groundwater for their domestic water supply. However, prior to 2008, the quality of the West Virginia’s groundwater resource was largely unknown. The need for a statewide assessment of groundwater quality prompted the U.S. Geological Survey (USGS), in cooperation with West Virginia Department of Environmental Protection (WVDEP)...
Authors
Douglas B. Chambers, Mark D. Kozar, Jeremy S. White, Katherine S. Paybins
Documentation of the Surface-Water Routing (SWR1) Process for modeling surface-water flow with the U.S. Geological Survey Modular Ground-Water Model (MODFLOW-2005) Documentation of the Surface-Water Routing (SWR1) Process for modeling surface-water flow with the U.S. Geological Survey Modular Ground-Water Model (MODFLOW-2005)
A flexible Surface-Water Routing (SWR1) Process that solves the continuity equation for one-dimensional and two-dimensional surface-water flow routing has been developed for the U.S. Geological Survey three-dimensional groundwater model, MODFLOW-2005. Simple level- and tilted-pool reservoir routing and a diffusive-wave approximation of the Saint-Venant equations have been implemented...
Authors
Joseph D. Hughes, Christian D. Langevin, Kevin L. Chartier, Jeremy T. White
Evaluating the effect of Tikhonov regularization schemes on predictions in a variable-density groundwater model Evaluating the effect of Tikhonov regularization schemes on predictions in a variable-density groundwater model
Calibration of highly‐parameterized numerical models typically requires explicit Tikhonovtype regularization to stabilize the inversion process. This regularization can take the form of a preferred parameter values scheme or preferred relations between parameters, such as the preferred equality scheme. The resulting parameter distributions calibrate the model to a user‐defined acceptable...
Authors
Jeremy T. White, Christian D. Langevin, Joseph D. Hughes
Use of time series and harmonic constituents of tidal propagation to enhance estimation of coastal aquifer heterogeneity Use of time series and harmonic constituents of tidal propagation to enhance estimation of coastal aquifer heterogeneity
A synthetic two‐dimensional model of a horizontally and vertically heterogeneous confined coastal aquifer system, based on the Upper Floridan aquifer in south Florida, USA, subjected to constant recharge and a complex tidal signal was used to generate 15‐minute water‐level data at select locations over a 7‐day simulation period. “Observed” water‐level data were generated by adding noise
Authors
Joseph D. Hughes, Jeremy T. White, Christian D. Langevin
Non-USGS Publications**
White, J.T., Fienen, M.N, and Doherty,J.E. 2016. A python framework for environmental model uncertainty analysis, Environmental Modelling & Software, Volume 85, Pages 217-228, ISSN 1364-8152
**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.