Jon Jeffrey Starn, Ph.D. (Former Employee)
Science and Products
Data for Three-dimensional distribution of groundwater residence time metrics in the glaciated United States using metamodels trained on general numerical simulation models
Residence time distribution (RTD) is a critically important characteristic of groundwater flow systems; however, it cannot be measured directly. RTD can be inferred from tracer data with analytical models (few parameters) or with numerical models (many parameters). The second approach permits more variation in system properties but is used less frequently than the first because large-scale numeric
Statistical summaries of simulated groundwater residence times for the 10 regional aquifers of the Northern Atlantic Coastal Plain aquifer system, at a 1 square-mile grid resolution
Groundwater residence times were simulated for the major regional aquifers of the Northern Atlantic Coastal Plain aquifer system from New York to North Carolina using particle tracking in a regional groundwater flow model. Millions of particles were distributed throughout the aquifers of the North Atlantic Coastal Plain in a MODFLOW model with a volume-weighted algorithm, then tracked backwards us
Thermal Infrared images and field data on areas of groundwater discharge in the Farmington River watershed
Areas of groundwater discharge are hydrologically and ecologically important, and yet are difficult to predict at the river network scale. Thermal infrared imagery can be used to identify areas of groundwater discharge based on an observed temperature anomaly (colder during the late summer or warmer during the late winter). The thermal images, direct temperature measurements (11 cm depth) and disc
National Multi Order Hydrologic Position (MOHP) Predictor Data for Groundwater and Groundwater-Quality Modeling
Multi Order Hydrologic Position (MOHP) raster datasets: Distance from Stream to Divide (DSD) and Lateral Position (LP) have been produced nationally for the 48 contiguous United States at a 30-meter resolution for stream orders 1 through 9. These data are available for testing as predictor variables for various regional and national groundwater-flow and groundwater-quality statistical models. The
Supporting Datasets Used in the General Groundwater-Model Construction System Version 0.1
General Groundwater-Model Construction System Version 0.1 (Genmod0.1) Groundwater residence-time distributions (GRTD) are critical for assessing lag times between activities at the land surface and the emergence of related solutes in the baseflow of streams. However, GRTD can not be measured directly, they must be inferred from an analysis of data using models. Glacial aquifers present challenge
Filter Total Items: 36
Groundwater residence times in glacial aquifers—A new general simulation-model approach compared to conventional inset models
Groundwater is important as a drinking-water source and for maintaining base flow in rivers, streams, and lakes. Groundwater quality can be predicted, in part, by its residence time in the subsurface, but the residence-time distribution cannot be measured directly and must be inferred from models. This report compares residence-time distributions from four areas where groundwater flow and travel t
Authors
J. Jeffrey Starn, Leon J. Kauffman, Daniel T. Feinstein
Predicted uranium and radon concentrations in New Hampshire (USA) groundwater—Using Multi Order Hydrologic Position as predictors
Two radioactive elements, uranium (U) and radon (Rn), which are of potential concern in New Hampshire (NH) groundwater, are investigated. Exceedance probability maps are tools to highlight locations where the concentrations of undesirable substances in the groundwater may be elevated. Two forms of statistical analysis are used to create exceedance probability maps for U and Rn in NH groundwater. T
Authors
Richard B. Moore, Kenneth Belitz, Joseph D. Ayotte, Terri L. Arnold, Laura Hayes, Jennifer B. Sharpe, J. Jeffrey Starn
Where groundwater seeps: Evaluating modeled groundwater discharge patterns with thermal infrared surveys at the river-network scale
Predicting baseflow dynamics, protecting aquatic habitat, and managing legacy contaminants requires explicit characterization and prediction of groundwater discharge patterns throughout river networks. Using handheld thermal infrared (TIR) cameras, we surveyed 47 km of stream length across the Farmington River watershed (1,570 km2; CT and MA, USA), mapping locations of bank and waterline groundwat
Authors
Janet R. Barclay, Martin A. Briggs, Eric Moore, J. Jeffrey Starn, Ann E.H. Hanson, Ashley Helton
Where groundwater seeps: Evaluating modeled groundwater discharge patterns with thermal infrared surveys at the river-network scale
Predicting baseflow dynamics, protecting aquatic habitat, and managing legacy contaminants requires explicit characterization and prediction of groundwater discharge patterns throughout river networks. Using handheld thermal infrared (TIR) cameras, we surveyed 47 km of stream length across the Farmington River watershed (1,570 km2; CT and MA, USA), mapping locations of bank and waterline groundwat
Authors
Janet R. Barclay, Martin A. Briggs, Eric Moore, J. Jeffrey Starn, Ann E.H. Hanson, Ashley Helton
Re‐purposing groundwater flow models for age assessments: Important characteristics
Groundwater flow model construction is often time‐consuming and costly, with development ideally focused on a specific purpose, such as quantifying well capture from water bodies or providing flow fields for simulating advective transport. As environmental challenges evolve, the incentive to re‐purpose existing groundwater flow models may increase. However, few studies have evaluated which charact
Authors
Paul F. Juckem, J. Jeffrey Starn
Three-dimensional distribution of residence time metrics in the glaciated United States using metamodels trained on general numerical models
Residence time distribution (RTD) is a critically important characteristic of groundwater flow systems; however, it cannot be measured directly. RTD can be inferred from tracer data with analytical models (few parameters) or with numerical models (many parameters). The second approach permits more variation in system properties but is used less frequently than the first because large‐scale numeric
Authors
J. Jeffrey Starn, Leon J. Kauffman, Carl S. Carlson, James E. Reddy, Michael N. Fienen
Improved prediction of management-relevant groundwater discharge characteristics throughout river networks
Groundwater discharge zones connect aquifers to surface water, generating baseflow and serving as ecosystem control points across aquatic ecosystems. The influence of groundwater discharge on surface flow connectivity, fate and transport of contaminants and nutrients, and thermal habitat depends strongly on hydrologic characteristics such as the spatial distribution, age, and depth of source groun
Authors
Janet R. Barclay, J. Jeffrey Starn, Martin A. Briggs, Ashley Helton
Multiorder hydrologic position in the conterminous United States: A set of metrics in support of groundwater mapping at regional and national scales
The location of a point on the landscape within a stream network (hydrologic position) can be an important predictive measure in hydrology. Hydrologic position is defined here by two metrics: lateral position and distance from stream to divide, both measured horizontally. Lateral position (dimensionless) is the relative position of a point between the stream and its watershed divide. Distance from
Authors
Kenneth Belitz, Richard B. Moore, Terri Arnold, Jennifer B. Sharpe, J. Jeffrey Starn
Regionalization of groundwater residence time using metamodeling
Groundwater residence-time distributions (RTDs) are critical for assessing susceptibility of water resources to degradation. A novel combination of numerical modeling and statistical methods allows estimation of regional RTDs with unprecedented speed. In this method, particle RTDs are generated in 30 type locales in the northeastern glaciated U.S using automated generalized finite-difference grou
Authors
J. Jeffrey Starn, Kenneth Belitz
Regional oxygen reduction and denitrification rates in groundwater from multi-model residence time distributions, San Joaquin Valley, USA
Rates of oxygen and nitrate reduction are key factors in determining the chemical evolution of groundwater. Little is known about how these rates vary and covary in regional groundwater settings, as few studies have focused on regional datasets with multiple tracers and methods of analysis that account for effects of mixed residence times on apparent reaction rates. This study provides insight int
Authors
Christopher T. Green, Bryant C. Jurgens, Yong Zhang, Jeffrey Starn, Michael J. Singleton, Bradley K. Esser
Scripting MODFLOW model development using Python and FloPy
Graphical user interfaces (GUIs) are commonly used to construct and postprocess numerical groundwater flow and transport models. Scripting model development with the programming language Python is presented here as an alternative approach. One advantage of Python is that there are many packages available to facilitate the model development process, including packages for plotting, array manipulati
Authors
Mark Bakker, Vincent E. A. Post, Christian D. Langevin, Joseph D. Hughes, Jeremy T. White, Jeffrey Starn, Michael N. Fienen
The effects of numerical-model complexity and observation type on estimated porosity values
The relative merits of model complexity and types of observations employed in model calibration are compared. An existing groundwater flow model coupled with an advective transport simulation of the Salt Lake Valley, Utah (USA), is adapted for advective transport, and effective porosity is adjusted until simulated tritium concentrations match concentrations in samples from wells. Two calibration a
Authors
Jeffrey Starn, Amvrossios C. Bagtzoglou, Christopher T. Green
Non-USGS Publications**
Starn, J.J., Bagtzoglou, A.C., and Robbins, G.A., 2010, Using atmospheric tracers to reduce uncertainty in groundwater recharge areas: Ground Water Volume 48, Issue 6, November/December 2010, Pages: 858–868. https://doi.org/10.1111/j.1745-6584.2010.00674.x
Starn, J.J., 2001, Analysis of uncertainty of contributing areas to wells using parameter estimation and Monte Carlo simulation: MODFLOW 2001 and Other Modeling Odysseys, September 11-14, 2001, Golden, Colorado, Proceedings: International Ground Water Modeling Center, Colorado School of Mines, and the U.S. Geological Survey, v. 1, p. 305-311.
Starn, J.J., 1994, Field application of nonlinear regression to estimate parameters of a two-dimensional ground-water flow model, in Proceedings, 1994 Groundwater Modeling Conference, Fort Collins, Colorado, August 10-12,1994: Colorado State University, p 575-582.
Starn, J.J., 1994, Apparent solute dispersion in an alluvial aquifer/stream system, in Morganwalp, D.W. and Aronson, D.A., eds., 1994, U.S. Geological Survey Toxic Substances Hydrology Program—Proceedings of the Technical Meeting, Colorado Springs, Colorado, September 20-24, 1993: U.S. Geological Survey Water- Resource Investigations Report 94- 4015, p 935-940. https://doi.org/10.3133/wri944015
**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
Data for Three-dimensional distribution of groundwater residence time metrics in the glaciated United States using metamodels trained on general numerical simulation models
Residence time distribution (RTD) is a critically important characteristic of groundwater flow systems; however, it cannot be measured directly. RTD can be inferred from tracer data with analytical models (few parameters) or with numerical models (many parameters). The second approach permits more variation in system properties but is used less frequently than the first because large-scale numeric
Statistical summaries of simulated groundwater residence times for the 10 regional aquifers of the Northern Atlantic Coastal Plain aquifer system, at a 1 square-mile grid resolution
Groundwater residence times were simulated for the major regional aquifers of the Northern Atlantic Coastal Plain aquifer system from New York to North Carolina using particle tracking in a regional groundwater flow model. Millions of particles were distributed throughout the aquifers of the North Atlantic Coastal Plain in a MODFLOW model with a volume-weighted algorithm, then tracked backwards us
Thermal Infrared images and field data on areas of groundwater discharge in the Farmington River watershed
Areas of groundwater discharge are hydrologically and ecologically important, and yet are difficult to predict at the river network scale. Thermal infrared imagery can be used to identify areas of groundwater discharge based on an observed temperature anomaly (colder during the late summer or warmer during the late winter). The thermal images, direct temperature measurements (11 cm depth) and disc
National Multi Order Hydrologic Position (MOHP) Predictor Data for Groundwater and Groundwater-Quality Modeling
Multi Order Hydrologic Position (MOHP) raster datasets: Distance from Stream to Divide (DSD) and Lateral Position (LP) have been produced nationally for the 48 contiguous United States at a 30-meter resolution for stream orders 1 through 9. These data are available for testing as predictor variables for various regional and national groundwater-flow and groundwater-quality statistical models. The
Supporting Datasets Used in the General Groundwater-Model Construction System Version 0.1
General Groundwater-Model Construction System Version 0.1 (Genmod0.1) Groundwater residence-time distributions (GRTD) are critical for assessing lag times between activities at the land surface and the emergence of related solutes in the baseflow of streams. However, GRTD can not be measured directly, they must be inferred from an analysis of data using models. Glacial aquifers present challenge
Filter Total Items: 36
Groundwater residence times in glacial aquifers—A new general simulation-model approach compared to conventional inset models
Groundwater is important as a drinking-water source and for maintaining base flow in rivers, streams, and lakes. Groundwater quality can be predicted, in part, by its residence time in the subsurface, but the residence-time distribution cannot be measured directly and must be inferred from models. This report compares residence-time distributions from four areas where groundwater flow and travel t
Authors
J. Jeffrey Starn, Leon J. Kauffman, Daniel T. Feinstein
Predicted uranium and radon concentrations in New Hampshire (USA) groundwater—Using Multi Order Hydrologic Position as predictors
Two radioactive elements, uranium (U) and radon (Rn), which are of potential concern in New Hampshire (NH) groundwater, are investigated. Exceedance probability maps are tools to highlight locations where the concentrations of undesirable substances in the groundwater may be elevated. Two forms of statistical analysis are used to create exceedance probability maps for U and Rn in NH groundwater. T
Authors
Richard B. Moore, Kenneth Belitz, Joseph D. Ayotte, Terri L. Arnold, Laura Hayes, Jennifer B. Sharpe, J. Jeffrey Starn
Where groundwater seeps: Evaluating modeled groundwater discharge patterns with thermal infrared surveys at the river-network scale
Predicting baseflow dynamics, protecting aquatic habitat, and managing legacy contaminants requires explicit characterization and prediction of groundwater discharge patterns throughout river networks. Using handheld thermal infrared (TIR) cameras, we surveyed 47 km of stream length across the Farmington River watershed (1,570 km2; CT and MA, USA), mapping locations of bank and waterline groundwat
Authors
Janet R. Barclay, Martin A. Briggs, Eric Moore, J. Jeffrey Starn, Ann E.H. Hanson, Ashley Helton
Where groundwater seeps: Evaluating modeled groundwater discharge patterns with thermal infrared surveys at the river-network scale
Predicting baseflow dynamics, protecting aquatic habitat, and managing legacy contaminants requires explicit characterization and prediction of groundwater discharge patterns throughout river networks. Using handheld thermal infrared (TIR) cameras, we surveyed 47 km of stream length across the Farmington River watershed (1,570 km2; CT and MA, USA), mapping locations of bank and waterline groundwat
Authors
Janet R. Barclay, Martin A. Briggs, Eric Moore, J. Jeffrey Starn, Ann E.H. Hanson, Ashley Helton
Re‐purposing groundwater flow models for age assessments: Important characteristics
Groundwater flow model construction is often time‐consuming and costly, with development ideally focused on a specific purpose, such as quantifying well capture from water bodies or providing flow fields for simulating advective transport. As environmental challenges evolve, the incentive to re‐purpose existing groundwater flow models may increase. However, few studies have evaluated which charact
Authors
Paul F. Juckem, J. Jeffrey Starn
Three-dimensional distribution of residence time metrics in the glaciated United States using metamodels trained on general numerical models
Residence time distribution (RTD) is a critically important characteristic of groundwater flow systems; however, it cannot be measured directly. RTD can be inferred from tracer data with analytical models (few parameters) or with numerical models (many parameters). The second approach permits more variation in system properties but is used less frequently than the first because large‐scale numeric
Authors
J. Jeffrey Starn, Leon J. Kauffman, Carl S. Carlson, James E. Reddy, Michael N. Fienen
Improved prediction of management-relevant groundwater discharge characteristics throughout river networks
Groundwater discharge zones connect aquifers to surface water, generating baseflow and serving as ecosystem control points across aquatic ecosystems. The influence of groundwater discharge on surface flow connectivity, fate and transport of contaminants and nutrients, and thermal habitat depends strongly on hydrologic characteristics such as the spatial distribution, age, and depth of source groun
Authors
Janet R. Barclay, J. Jeffrey Starn, Martin A. Briggs, Ashley Helton
Multiorder hydrologic position in the conterminous United States: A set of metrics in support of groundwater mapping at regional and national scales
The location of a point on the landscape within a stream network (hydrologic position) can be an important predictive measure in hydrology. Hydrologic position is defined here by two metrics: lateral position and distance from stream to divide, both measured horizontally. Lateral position (dimensionless) is the relative position of a point between the stream and its watershed divide. Distance from
Authors
Kenneth Belitz, Richard B. Moore, Terri Arnold, Jennifer B. Sharpe, J. Jeffrey Starn
Regionalization of groundwater residence time using metamodeling
Groundwater residence-time distributions (RTDs) are critical for assessing susceptibility of water resources to degradation. A novel combination of numerical modeling and statistical methods allows estimation of regional RTDs with unprecedented speed. In this method, particle RTDs are generated in 30 type locales in the northeastern glaciated U.S using automated generalized finite-difference grou
Authors
J. Jeffrey Starn, Kenneth Belitz
Regional oxygen reduction and denitrification rates in groundwater from multi-model residence time distributions, San Joaquin Valley, USA
Rates of oxygen and nitrate reduction are key factors in determining the chemical evolution of groundwater. Little is known about how these rates vary and covary in regional groundwater settings, as few studies have focused on regional datasets with multiple tracers and methods of analysis that account for effects of mixed residence times on apparent reaction rates. This study provides insight int
Authors
Christopher T. Green, Bryant C. Jurgens, Yong Zhang, Jeffrey Starn, Michael J. Singleton, Bradley K. Esser
Scripting MODFLOW model development using Python and FloPy
Graphical user interfaces (GUIs) are commonly used to construct and postprocess numerical groundwater flow and transport models. Scripting model development with the programming language Python is presented here as an alternative approach. One advantage of Python is that there are many packages available to facilitate the model development process, including packages for plotting, array manipulati
Authors
Mark Bakker, Vincent E. A. Post, Christian D. Langevin, Joseph D. Hughes, Jeremy T. White, Jeffrey Starn, Michael N. Fienen
The effects of numerical-model complexity and observation type on estimated porosity values
The relative merits of model complexity and types of observations employed in model calibration are compared. An existing groundwater flow model coupled with an advective transport simulation of the Salt Lake Valley, Utah (USA), is adapted for advective transport, and effective porosity is adjusted until simulated tritium concentrations match concentrations in samples from wells. Two calibration a
Authors
Jeffrey Starn, Amvrossios C. Bagtzoglou, Christopher T. Green
Non-USGS Publications**
Starn, J.J., Bagtzoglou, A.C., and Robbins, G.A., 2010, Using atmospheric tracers to reduce uncertainty in groundwater recharge areas: Ground Water Volume 48, Issue 6, November/December 2010, Pages: 858–868. https://doi.org/10.1111/j.1745-6584.2010.00674.x
Starn, J.J., 2001, Analysis of uncertainty of contributing areas to wells using parameter estimation and Monte Carlo simulation: MODFLOW 2001 and Other Modeling Odysseys, September 11-14, 2001, Golden, Colorado, Proceedings: International Ground Water Modeling Center, Colorado School of Mines, and the U.S. Geological Survey, v. 1, p. 305-311.
Starn, J.J., 1994, Field application of nonlinear regression to estimate parameters of a two-dimensional ground-water flow model, in Proceedings, 1994 Groundwater Modeling Conference, Fort Collins, Colorado, August 10-12,1994: Colorado State University, p 575-582.
Starn, J.J., 1994, Apparent solute dispersion in an alluvial aquifer/stream system, in Morganwalp, D.W. and Aronson, D.A., eds., 1994, U.S. Geological Survey Toxic Substances Hydrology Program—Proceedings of the Technical Meeting, Colorado Springs, Colorado, September 20-24, 1993: U.S. Geological Survey Water- Resource Investigations Report 94- 4015, p 935-940. https://doi.org/10.3133/wri944015
**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.