Christian Langevin (Former Employee)
Science and Products
Filter Total Items: 71
U.S. Geological Survey Science Support Strategy for Biscayne National Park and Surrounding Areas in Southeastern Florida U.S. Geological Survey Science Support Strategy for Biscayne National Park and Surrounding Areas in Southeastern Florida
The U.S. Geological Survey conducts a wide range of research in and around the Biscayne National Park region of southern Florida. This research encompasses the biologic, ecologic, meteorologic, geologic, and hydrologic components of the system, including water-quality analyses, ground-water modeling, hydrogeologic-data collection, ecologic-habitat evaluations, wetlands characterizations
Authors
Melinda A. Wolfert-Lohmann, Christian D. Langevin, Sonya A. Jones, Chris D. Reich, Georgina L. Wingard, Ilsa B. Kuffner, Kevin J. Cunningham
SEAWAT Version 4: A Computer Program for Simulation of Multi-Species Solute and Heat Transport SEAWAT Version 4: A Computer Program for Simulation of Multi-Species Solute and Heat Transport
The SEAWAT program is a coupled version of MODFLOW and MT3DMS designed to simulate three-dimensional, variable-density, saturated ground-water flow. Flexible equations were added to the program to allow fluid density to be calculated as a function of one or more MT3DMS species. Fluid density may also be calculated as a function of fluid pressure. The effect of fluid viscosity variations...
Authors
Christian D. Langevin, Daniel T. Thorne, Alyssa M. Dausman, Michael C. Sukop, Weixing Guo
Modeling axisymmetric flow and transport Modeling axisymmetric flow and transport
Unmodified versions of common computer programs such as MODFLOW, MT3DMS, and SEAWAT that use Cartesian geometry can accurately simulate axially symmetric ground water flow and solute transport. Axisymmetric flow and transport are simulated by adjusting several input parameters to account for the increase in flow area with radial distance from the injection or extraction well. Logarithmic...
Authors
C.D. Langevin
Utilizing spectral analysis of coastal discharge computed by a numerical model to determine boundary influence Utilizing spectral analysis of coastal discharge computed by a numerical model to determine boundary influence
In the present study, a spectral analysis was applied to field data and a numerical model of southeastern Everglades and northeastern Florida Bay that involved computing and comparing the power spectrum of simulated and measured flows at the primary coastal outflow creek. Four dominant power frequencies, corresponding to the S1, S2, M2, and 01 tidal periods, were apparent in the measured...
Authors
E.D. Swain, C.D. Langevin, J.D. Wang
Application of FTLOADDS to Simulate Flow, Salinity, and Surface-Water Stage in the Southern Everglades, Florida Application of FTLOADDS to Simulate Flow, Salinity, and Surface-Water Stage in the Southern Everglades, Florida
The Comprehensive Everglades Restoration Plan requires numerical modeling to achieve a sufficient understanding of coastal freshwater flows, nutrient sources, and the evaluation of management alternatives to restore the ecosystem of southern Florida. Numerical models include a regional water-management model to represent restoration changes to the hydrology of southern Florida and a...
Authors
John D. Wang, Eric D. Swain, Melinda A. Wolfert, Christian D. Langevin, Dawn E. James, Pamela A. Telis
Effect of tidal fluctuations on contaminant transfer to the ocean Effect of tidal fluctuations on contaminant transfer to the ocean
Variable-density groundwater flow was simulated to examine the effects that tide has on the coastward migration of a contaminant through a freshwater/saltwater interface and toward a coastal ocean boundary. Simulated ocean tides did not significantly affect the total contaminant mass input to the ocean; however, the difference in tidal and non-tidal simulated concentrations could be as...
Authors
I.L. Licata, C.D. Langevin, A.M. Dausman
Science and Products
Filter Total Items: 71
U.S. Geological Survey Science Support Strategy for Biscayne National Park and Surrounding Areas in Southeastern Florida U.S. Geological Survey Science Support Strategy for Biscayne National Park and Surrounding Areas in Southeastern Florida
The U.S. Geological Survey conducts a wide range of research in and around the Biscayne National Park region of southern Florida. This research encompasses the biologic, ecologic, meteorologic, geologic, and hydrologic components of the system, including water-quality analyses, ground-water modeling, hydrogeologic-data collection, ecologic-habitat evaluations, wetlands characterizations
Authors
Melinda A. Wolfert-Lohmann, Christian D. Langevin, Sonya A. Jones, Chris D. Reich, Georgina L. Wingard, Ilsa B. Kuffner, Kevin J. Cunningham
SEAWAT Version 4: A Computer Program for Simulation of Multi-Species Solute and Heat Transport SEAWAT Version 4: A Computer Program for Simulation of Multi-Species Solute and Heat Transport
The SEAWAT program is a coupled version of MODFLOW and MT3DMS designed to simulate three-dimensional, variable-density, saturated ground-water flow. Flexible equations were added to the program to allow fluid density to be calculated as a function of one or more MT3DMS species. Fluid density may also be calculated as a function of fluid pressure. The effect of fluid viscosity variations...
Authors
Christian D. Langevin, Daniel T. Thorne, Alyssa M. Dausman, Michael C. Sukop, Weixing Guo
Modeling axisymmetric flow and transport Modeling axisymmetric flow and transport
Unmodified versions of common computer programs such as MODFLOW, MT3DMS, and SEAWAT that use Cartesian geometry can accurately simulate axially symmetric ground water flow and solute transport. Axisymmetric flow and transport are simulated by adjusting several input parameters to account for the increase in flow area with radial distance from the injection or extraction well. Logarithmic...
Authors
C.D. Langevin
Utilizing spectral analysis of coastal discharge computed by a numerical model to determine boundary influence Utilizing spectral analysis of coastal discharge computed by a numerical model to determine boundary influence
In the present study, a spectral analysis was applied to field data and a numerical model of southeastern Everglades and northeastern Florida Bay that involved computing and comparing the power spectrum of simulated and measured flows at the primary coastal outflow creek. Four dominant power frequencies, corresponding to the S1, S2, M2, and 01 tidal periods, were apparent in the measured...
Authors
E.D. Swain, C.D. Langevin, J.D. Wang
Application of FTLOADDS to Simulate Flow, Salinity, and Surface-Water Stage in the Southern Everglades, Florida Application of FTLOADDS to Simulate Flow, Salinity, and Surface-Water Stage in the Southern Everglades, Florida
The Comprehensive Everglades Restoration Plan requires numerical modeling to achieve a sufficient understanding of coastal freshwater flows, nutrient sources, and the evaluation of management alternatives to restore the ecosystem of southern Florida. Numerical models include a regional water-management model to represent restoration changes to the hydrology of southern Florida and a...
Authors
John D. Wang, Eric D. Swain, Melinda A. Wolfert, Christian D. Langevin, Dawn E. James, Pamela A. Telis
Effect of tidal fluctuations on contaminant transfer to the ocean Effect of tidal fluctuations on contaminant transfer to the ocean
Variable-density groundwater flow was simulated to examine the effects that tide has on the coastward migration of a contaminant through a freshwater/saltwater interface and toward a coastal ocean boundary. Simulated ocean tides did not significantly affect the total contaminant mass input to the ocean; however, the difference in tidal and non-tidal simulated concentrations could be as...
Authors
I.L. Licata, C.D. Langevin, A.M. Dausman