Christian Langevin (Former Employee)
Science and Products
Filter Total Items: 71
Effect of the difference between water-table elevation and hydraulic head on simulation of unconfined aquifers using MODFLOW Effect of the difference between water-table elevation and hydraulic head on simulation of unconfined aquifers using MODFLOW
No abstract available.
Authors
Alden M. Provost, Christian D. Langevin
Predictive uncertainty analysis of a saltwater intrusion model using null-space Monte Carlo Predictive uncertainty analysis of a saltwater intrusion model using null-space Monte Carlo
Because of the extensive computational burden and perhaps a lack of awareness of existing methods, rigorous uncertainty analyses are rarely conducted for variable-density flow and transport models. For this reason, a recently developed null-space Monte Carlo (NSMC) method for quantifying prediction uncertainty was tested for a synthetic saltwater intrusion model patterned after the Henry...
Authors
Daan Herckenrath, Christian D. Langevin, John Doherty
Tidal Boundary Conditions in SEAWAT Tidal Boundary Conditions in SEAWAT
SEAWAT, a U.S. Geological Survey groundwater flow and transport code, is increasingly used to model the effects of tidal motion on coastal aquifers. Different options are available to simulate tidal boundaries but no guidelines exist nor have comparisons been made to identify the most effective approach. We test seven methods to simulate a sloping beach and a tidal flat. The ocean is...
Authors
Ann E. Mulligan, Christian Langevin, Vincent Post
Effect of tidal fluctuations on transient dispersion of simulated contaminant concentrations in coastal aquifers Effect of tidal fluctuations on transient dispersion of simulated contaminant concentrations in coastal aquifers
Variable-density groundwater models require extensive computational resources, particularly for simulations representing short-term hydrologic variability such as tidal fluctuations. Saltwater-intrusion models usually neglect tidal fluctuations and this may introduce errors in simulated concentrations. The effects of tides on simulated concentrations in a coastal aquifer were assessed...
Authors
Ivana La Licata, Christian D. Langevin, Alyssa M. Dausman, Luca Alberti
Use of hydrologic and hydrodynamic modeling for ecosystem restoration Use of hydrologic and hydrodynamic modeling for ecosystem restoration
Planning and implementation of unprecedented projects for restoring the greater Everglades ecosystem are underway and the hydrologic and hydrodynamic modeling of restoration alternatives has become essential for success of restoration efforts. In view of the complex nature of the South Florida water resources system, regional-scale (system-wide) hydrologic models have been developed and...
Authors
J. Obeysekera, L. Kuebler, S. Ahmed, M.-L. Chang, V. Engel, Christian D. Langevin, Eric D. Swain, Y. Wan
Use of upscaled elevation and surface roughness data in two-dimensional surface water models Use of upscaled elevation and surface roughness data in two-dimensional surface water models
In this paper, we present an approach that uses a combination of cell-block- and cell-face-averaging of high-resolution cell elevation and roughness data to upscale hydraulic parameters and accurately simulate surface water flow in relatively low-resolution numerical models. The method developed allows channelized features that preferentially connect large-scale grid cells at cell...
Authors
J.D. Hughes, J.D. Decker, C.D. Langevin
Science and Products
Filter Total Items: 71
Effect of the difference between water-table elevation and hydraulic head on simulation of unconfined aquifers using MODFLOW Effect of the difference between water-table elevation and hydraulic head on simulation of unconfined aquifers using MODFLOW
No abstract available.
Authors
Alden M. Provost, Christian D. Langevin
Predictive uncertainty analysis of a saltwater intrusion model using null-space Monte Carlo Predictive uncertainty analysis of a saltwater intrusion model using null-space Monte Carlo
Because of the extensive computational burden and perhaps a lack of awareness of existing methods, rigorous uncertainty analyses are rarely conducted for variable-density flow and transport models. For this reason, a recently developed null-space Monte Carlo (NSMC) method for quantifying prediction uncertainty was tested for a synthetic saltwater intrusion model patterned after the Henry...
Authors
Daan Herckenrath, Christian D. Langevin, John Doherty
Tidal Boundary Conditions in SEAWAT Tidal Boundary Conditions in SEAWAT
SEAWAT, a U.S. Geological Survey groundwater flow and transport code, is increasingly used to model the effects of tidal motion on coastal aquifers. Different options are available to simulate tidal boundaries but no guidelines exist nor have comparisons been made to identify the most effective approach. We test seven methods to simulate a sloping beach and a tidal flat. The ocean is...
Authors
Ann E. Mulligan, Christian Langevin, Vincent Post
Effect of tidal fluctuations on transient dispersion of simulated contaminant concentrations in coastal aquifers Effect of tidal fluctuations on transient dispersion of simulated contaminant concentrations in coastal aquifers
Variable-density groundwater models require extensive computational resources, particularly for simulations representing short-term hydrologic variability such as tidal fluctuations. Saltwater-intrusion models usually neglect tidal fluctuations and this may introduce errors in simulated concentrations. The effects of tides on simulated concentrations in a coastal aquifer were assessed...
Authors
Ivana La Licata, Christian D. Langevin, Alyssa M. Dausman, Luca Alberti
Use of hydrologic and hydrodynamic modeling for ecosystem restoration Use of hydrologic and hydrodynamic modeling for ecosystem restoration
Planning and implementation of unprecedented projects for restoring the greater Everglades ecosystem are underway and the hydrologic and hydrodynamic modeling of restoration alternatives has become essential for success of restoration efforts. In view of the complex nature of the South Florida water resources system, regional-scale (system-wide) hydrologic models have been developed and...
Authors
J. Obeysekera, L. Kuebler, S. Ahmed, M.-L. Chang, V. Engel, Christian D. Langevin, Eric D. Swain, Y. Wan
Use of upscaled elevation and surface roughness data in two-dimensional surface water models Use of upscaled elevation and surface roughness data in two-dimensional surface water models
In this paper, we present an approach that uses a combination of cell-block- and cell-face-averaging of high-resolution cell elevation and roughness data to upscale hydraulic parameters and accurately simulate surface water flow in relatively low-resolution numerical models. The method developed allows channelized features that preferentially connect large-scale grid cells at cell...
Authors
J.D. Hughes, J.D. Decker, C.D. Langevin