Jacob Knight
Jacob Knight is a Hydrologist in the Arizona Water Science Center, Tucson Office.
Science and Products
MODFLOW 6 model and ensemble used in the simulation of groundwater flow and land subsidence in the northern part of the Gulf Coast aquifer, 1897-2018 (ver. 2.0, September 2023)
The U.S. Geological Survey (USGS), in cooperation with the Harris-Galveston Subsidence District and Fort Bend Subsidence District, constructed a finite-difference numerical groundwater-flow model of the northern Gulf Coast aquifer region for 1897 through 2018 using MODFLOW 6 with the Newton formulation solver to simulate groundwater flow and land-surface subsidence. Model parameter estimation and
Soil-Water-Balance (SWB) model archive used to simulate potential mean annual recharge in the Grand Canyon region, Arizona
This model archive contains the Soil-Water-Balance (SWB) model used to simulate potential mean annual recharge in the Grand Canyon region for 1981 through 2016. The simulated results are described in the associated U.S. Geological Survey Scientific Investigations Report 2022-5037. The model archive includes all the necessary files to document and run the SWB model and process the results as displa
MODFLOW-NWT groundwater model used for simulating a potential future pumping scenario and forecasting associated groundwater-level changes in the Hualapai Valley, Northwestern Arizona.
A numerical groundwater flow model of the Hualapai Valley Basin, using MODFLOW-NWT, was developed to assist water-resource managers in understanding the potential effects of projected groundwater withdrawals on groundwater levels in the basin. Hualapai Valley Basin is a broad, internally drained, intermountain desert basin in Mohave County, northwestern Arizona. Basin-fill aquifers are the primary
Data Release for the Binational Study of the Transboundary San Pedro Aquifer, Transboundary Aquifer Assessment Program
This is a data release of data presented in the report "Binational Study of the Transboundary San Pedro Aquifer", Callegary and others, 2016. The United States and Mexico share waters in a number of hydrological basins and aquifers that cross the International Boundary. Both the United States and Mexico recognize that, in a region of scarce water and expanding populations, better scientific
Hydrogeology, land-surface subsidence, and documentation of the Gulf Coast Land Subsidence and Groundwater-Flow (GULF) model, southeast Texas, 1897–2018
Executive SummaryAs a part of the Texas Water Development Board groundwater availability modeling program, the U.S. Geological Survey developed the Gulf Coast Land Subsidence and Groundwater-Flow model (hereinafter, the “GULF model”) and ensemble to simulate groundwater flow and land-surface subsidence in the northern part of the Gulf Coast aquifer system (the study area) in Texas from predevelopm
Authors
J.H. Ellis, Jacob E. Knight, Jeremy T. White, Michelle Sneed, Joseph D. Hughes, Jason K. Ramage, Christopher L. Braun, Andrew Teeple, Linzy K. Foster, Samuel H. Rendon, Justin T. Brandt
Conceptual models of groundwater flow in the Grand Canyon region, Arizona
The conceptual models of groundwater flow outlined herein synthesize what is known and hypothesized about the groundwater-flow systems that discharge to the Grand Canyon of Arizona. These models interpret the hydrogeologic characteristics and hydrologic dynamics of the physical systems into a framework for understanding key aspects of the physical systems as they relate to groundwater flow and con
Authors
Jacob E. Knight, Peter W. Huntoon
Improving groundwater model calibration with repeat microgravity measurements
Groundwater-flow models depend on hydraulic head and flux observations for evaluation and calibration. A different type of observation—change in storage measured using repeat microgravity—can also be used for parameter estimation by simulating the expected change in gravity from a groundwater model and including the observation misfit in the objective function. The method is demonstrated using new
Authors
Jeffrey Kennedy, Libby M. Kahler, Jacob E. Knight, Joshua D. Larson
Assessing potential groundwater-level declines from future withdrawals in the Hualapai Valley, northwestern Arizona
A numerical groundwater flow model of the Hualapai Valley Basin in northwestern Arizona was developed to assist water-resource managers in understanding the potential effects of projected groundwater withdrawals on groundwater levels in the basin. The Hualapai Valley Hydrologic Model (HVHM) simulates the hydrologic system for the years 1935 through 2219, including future withdrawal scenarios that
Authors
Jacob E. Knight, Bruce Gungle, Jeffrey R. Kennedy
Groundwater availability in the Truxton basin, northwestern Arizona
This is a summary chapter of a multichapter volume that includes a brief description of the study area and descriptions of the hydrogeologic framework, numerical groundwater-flow model, and estimates of simulated changes to groundwater levels of the Truxton aquifer.
Authors
Jon P. Mason, Jacob E. Knight, Lyndsay B. Ball, Jeffrey R. Kennedy, Donald J. Bills, Jamie P. Macy
Integrated hydrologic modeling of a transboundary aquifer system —Lower Rio Grande
For more than 30 years the agreements developed for the aquifer systems of the lower Rio Grande and related river compacts of the Rio Grande River have evolved into a complex setting of transboundary conjunctive use. The conjunctive use now includes many facets of water rights, water use, and emerging demands between the states of New Mexico and Texas, the United States and Mexico, and various wat
Authors
Randall T. Hanson, Wolfgang Schmid, Jacob E. Knight, Thomas Maddock
Science and Products
- Data
MODFLOW 6 model and ensemble used in the simulation of groundwater flow and land subsidence in the northern part of the Gulf Coast aquifer, 1897-2018 (ver. 2.0, September 2023)
The U.S. Geological Survey (USGS), in cooperation with the Harris-Galveston Subsidence District and Fort Bend Subsidence District, constructed a finite-difference numerical groundwater-flow model of the northern Gulf Coast aquifer region for 1897 through 2018 using MODFLOW 6 with the Newton formulation solver to simulate groundwater flow and land-surface subsidence. Model parameter estimation andSoil-Water-Balance (SWB) model archive used to simulate potential mean annual recharge in the Grand Canyon region, Arizona
This model archive contains the Soil-Water-Balance (SWB) model used to simulate potential mean annual recharge in the Grand Canyon region for 1981 through 2016. The simulated results are described in the associated U.S. Geological Survey Scientific Investigations Report 2022-5037. The model archive includes all the necessary files to document and run the SWB model and process the results as displaMODFLOW-NWT groundwater model used for simulating a potential future pumping scenario and forecasting associated groundwater-level changes in the Hualapai Valley, Northwestern Arizona.
A numerical groundwater flow model of the Hualapai Valley Basin, using MODFLOW-NWT, was developed to assist water-resource managers in understanding the potential effects of projected groundwater withdrawals on groundwater levels in the basin. Hualapai Valley Basin is a broad, internally drained, intermountain desert basin in Mohave County, northwestern Arizona. Basin-fill aquifers are the primaryData Release for the Binational Study of the Transboundary San Pedro Aquifer, Transboundary Aquifer Assessment Program
This is a data release of data presented in the report "Binational Study of the Transboundary San Pedro Aquifer", Callegary and others, 2016. The United States and Mexico share waters in a number of hydrological basins and aquifers that cross the International Boundary. Both the United States and Mexico recognize that, in a region of scarce water and expanding populations, better scientific - Publications
Hydrogeology, land-surface subsidence, and documentation of the Gulf Coast Land Subsidence and Groundwater-Flow (GULF) model, southeast Texas, 1897–2018
Executive SummaryAs a part of the Texas Water Development Board groundwater availability modeling program, the U.S. Geological Survey developed the Gulf Coast Land Subsidence and Groundwater-Flow model (hereinafter, the “GULF model”) and ensemble to simulate groundwater flow and land-surface subsidence in the northern part of the Gulf Coast aquifer system (the study area) in Texas from predevelopmAuthorsJ.H. Ellis, Jacob E. Knight, Jeremy T. White, Michelle Sneed, Joseph D. Hughes, Jason K. Ramage, Christopher L. Braun, Andrew Teeple, Linzy K. Foster, Samuel H. Rendon, Justin T. BrandtConceptual models of groundwater flow in the Grand Canyon region, Arizona
The conceptual models of groundwater flow outlined herein synthesize what is known and hypothesized about the groundwater-flow systems that discharge to the Grand Canyon of Arizona. These models interpret the hydrogeologic characteristics and hydrologic dynamics of the physical systems into a framework for understanding key aspects of the physical systems as they relate to groundwater flow and conAuthorsJacob E. Knight, Peter W. HuntoonImproving groundwater model calibration with repeat microgravity measurements
Groundwater-flow models depend on hydraulic head and flux observations for evaluation and calibration. A different type of observation—change in storage measured using repeat microgravity—can also be used for parameter estimation by simulating the expected change in gravity from a groundwater model and including the observation misfit in the objective function. The method is demonstrated using newAuthorsJeffrey Kennedy, Libby M. Kahler, Jacob E. Knight, Joshua D. LarsonAssessing potential groundwater-level declines from future withdrawals in the Hualapai Valley, northwestern Arizona
A numerical groundwater flow model of the Hualapai Valley Basin in northwestern Arizona was developed to assist water-resource managers in understanding the potential effects of projected groundwater withdrawals on groundwater levels in the basin. The Hualapai Valley Hydrologic Model (HVHM) simulates the hydrologic system for the years 1935 through 2219, including future withdrawal scenarios thatAuthorsJacob E. Knight, Bruce Gungle, Jeffrey R. KennedyGroundwater availability in the Truxton basin, northwestern Arizona
This is a summary chapter of a multichapter volume that includes a brief description of the study area and descriptions of the hydrogeologic framework, numerical groundwater-flow model, and estimates of simulated changes to groundwater levels of the Truxton aquifer.AuthorsJon P. Mason, Jacob E. Knight, Lyndsay B. Ball, Jeffrey R. Kennedy, Donald J. Bills, Jamie P. MacyIntegrated hydrologic modeling of a transboundary aquifer system —Lower Rio Grande
For more than 30 years the agreements developed for the aquifer systems of the lower Rio Grande and related river compacts of the Rio Grande River have evolved into a complex setting of transboundary conjunctive use. The conjunctive use now includes many facets of water rights, water use, and emerging demands between the states of New Mexico and Texas, the United States and Mexico, and various watAuthorsRandall T. Hanson, Wolfgang Schmid, Jacob E. Knight, Thomas Maddock