John F Walker (Former Employee)
Science and Products
Filter Total Items: 42
Flood-frequency characteristics of Wisconsin streams
Flood-frequency characteristics for 360 gaged sites on unregulated rural streams in Wisconsin are presented for percent annual exceedance probabilities ranging from 0.2 to 50 using a statewide skewness map developed for this report. Equations of the relations between flood-frequency and drainage-basin characteristics were developed by multiple-regression analyses. Flood-frequency...
Authors
John F. Walker, Marie C. Peppler, Mari Danz, Laura E. Hubbard
Simulation of climate-change effects on streamflow, lake water budgets, and stream temperature using GSFLOW and SNTEMP, Trout Lake Watershed, Wisconsin
Although groundwater and surface water are considered a single resource, historically hydrologic simulations have not accounted for feedback loops between the groundwater system and other hydrologic processes. These feedbacks include timing and rates of evapotranspiration, surface runoff, soil-zone flow, and interactions with the groundwater system. Simulations that iteratively couple...
Authors
Randall Hunt, John F. Walker, William R. Selbig, Stephen M. Westenbroek, R. Steve Regan
Potential effects of climate change on inland glacial lakes and implications for lake-dependent biota in Wisconsin: final report April 2013
The economic vitality and quality of life of many northern Wisconsin communities is closely associated with the ecological condition of the abundant water resources in the region. Climate change models predict warmer temperatures, changes to precipitation patterns, and increased evapotranspiration in the Great Lakes region. Recently (1950-2006), many regions of Wisconsin have experienced...
Authors
Michael Frederick Meyer, John F. Walker, Kevin P. Kenow, Paul W. Rasmussen, Paul J. Garrison, Paul R. Hanson, Randall Hunt
Approaches in highly parameterized inversion: TSPROC, a general time-series processor to assist in model calibration and result summarization
The TSPROC (Time Series PROCessor) computer software uses a simple scripting language to process and analyze time series. It was developed primarily to assist in the calibration of environmental models. The software is designed to perform calculations on time-series data commonly associated with surface-water models, including calculation of flow volumes, transformation by means of basic...
Authors
Stephen M. Westenbroek, John E. Doherty, John F. Walker, Victor A. Kelson, Randall Hunt, Timothy B. Cera
Watershed scale response to climate change--Black Earth Creek Basin, Wisconsin
General Circulation Model simulations of future climate through 2099 project a wide range of possible scenarios. To determine the sensitivity and potential effect of long-term climate change on the freshwater resources of the United States, the U.S. Geological Survey Global Change study, "An integrated watershed scale response to global change in selected basins across the United States"...
Authors
Randall Hunt, John F. Walker, Steven M. Westenbroek, Lauren Hay, Steven L. Markstrom
Watershed scale response to climate change--Trout Lake Basin, Wisconsin
General Circulation Model simulations of future climate through 2099 project a wide range of possible scenarios. To determine the sensitivity and potential effect of long-term climate change on the freshwater resources of the United States, the U.S. Geological Survey Global Change study, "An integrated watershed scale response to global change in selected basins across the United States"...
Authors
John F. Walker, Randall Hunt, Lauren Hay, Steven L. Markstrom
Integrated watershed-scale response to climate change for selected basins across the United States
A study by the U.S. Geological Survey (USGS) evaluated the hydrologic response to different projected carbon emission scenarios of the 21st century using a hydrologic simulation model. This study involved five major steps: (1) setup, calibrate and evaluated the Precipitation Runoff Modeling System (PRMS) model in 14 basins across the United States by local USGS personnel; (2) acquire...
Authors
Steven L. Markstrom, Lauren Hay, Christian D. Ward-Garrison, John Risley, William Battaglin, David M. Bjerklie, Katherine J. Chase, Daniel E. Christiansen, Robert W. Dudley, Randall Hunt, Kathryn M. Koczot, Mark C. Mastin, R. Steve Regan, Roland J. Viger, Kevin C. Vining, John F. Walker
Effects of best-management practices in Eagle and Joos Valley Creeks in the Waumandee Creek Priority Watershed, Wisconsin, 1990-2007
In many watersheds, nonpoint-source contamination is a major contributor to water-quality problems. In response to the recognition of the importance of nonpoint sources, the Wisconsin Nonpoint Source Water Pollution Abatement Program (Nonpoint Program) was enacted in 1978. This report summarizes the results of a study to assess the effectiveness of watershed-management practices for...
Authors
David J. Graczyk, John F. Walker, Roger T. Bannerman, Troy D. Rutter
Groundwater recharge in Wisconsin— Annual estimates for 1970–99 using streamflow data
The groundwater component of streamflow is important because it is indicative of the sustained flow of a stream during dry periods, is often of better quality, and has a smaller range of temperatures, than surface contributions to streamflow. All three of these characteristics are important to the health of aquatic life in a stream. If recharge to the aquifers is to be preserved or...
Authors
Warren A. Gebert, John F. Walker, Randall Hunt
Estimating 1970-99 average annual groundwater recharge in Wisconsin using streamflow data
Average annual recharge in Wisconsin for the period 1970-99 was estimated using streamflow data from U.S. Geological Survey continuous-record streamflow-gaging stations and partial-record sites. Partial-record sites have discharge measurements collected during low-flow conditions. The average annual base flow of a stream divided by the drainage area is a good approximation of the...
Authors
Warren A. Gebert, John F. Walker, James L. Kennedy
Characterizing climate-change impacts on the 1.5-yr flood flow in selected basins across the United States: a probabilistic approach
The U.S. Geological Survey Precipitation-Runoff Modeling System (PRMS) model was applied to basins in 14 different hydroclimatic regions to determine the sensitivity and variability of the freshwater resources of the United States in the face of current climate-change projections. Rather than attempting to choose a most likely scenario from the results of the Intergovernmental Panel on...
Authors
John F. Walker, Lauren Hay, Steven L. Markstrom, Michael D. Dettinger
Using a coupled groundwater/surface-water model to predict climate-change impacts to lakes in the Trout Lake Watershed, northern Wisconsin
A major focus of the U.S. Geological Survey’s Trout Lake Water, Energy, and Biogeochemical Budgets (WEBB) project is the development of a watershed model to allow predictions of hydrologic response to future conditions including land-use and climate change. The coupled groundwater/surface-water model GSFLOW was chosen for this purpose because it could easily incorporate an existing...
Authors
Randall Hunt, John F. Walker, Steven L. Markstrom, Lauren Hay, John E. Doherty
Next Generation Water Observing System: Illinois River Basin
The Next Generation Water Observing System provides high-fidelity, real-time data on water quantity, quality, and use to support modern water prediction and decision-support systems that are necessary for informing water operations on a daily basis and decision-making during water emergencies. The Illinois River Basin provides an opportunity to implement the NGWOS in a system challenged by an...
Flood frequency in Wisconsin
Flood-frequency estimates are required at many sites for bridge and culvert design, as well as for flood-plain management and flood-insurance studies. To estimate flood frequency at ungaged locations, a network of approximately 90 crest-stage gages and more than 200 past and current continuous-record gages are used to compute regional flood-frequency equations to estimate floods at ungaged sites.
Science and Products
Filter Total Items: 42
Flood-frequency characteristics of Wisconsin streams
Flood-frequency characteristics for 360 gaged sites on unregulated rural streams in Wisconsin are presented for percent annual exceedance probabilities ranging from 0.2 to 50 using a statewide skewness map developed for this report. Equations of the relations between flood-frequency and drainage-basin characteristics were developed by multiple-regression analyses. Flood-frequency...
Authors
John F. Walker, Marie C. Peppler, Mari Danz, Laura E. Hubbard
Simulation of climate-change effects on streamflow, lake water budgets, and stream temperature using GSFLOW and SNTEMP, Trout Lake Watershed, Wisconsin
Although groundwater and surface water are considered a single resource, historically hydrologic simulations have not accounted for feedback loops between the groundwater system and other hydrologic processes. These feedbacks include timing and rates of evapotranspiration, surface runoff, soil-zone flow, and interactions with the groundwater system. Simulations that iteratively couple...
Authors
Randall Hunt, John F. Walker, William R. Selbig, Stephen M. Westenbroek, R. Steve Regan
Potential effects of climate change on inland glacial lakes and implications for lake-dependent biota in Wisconsin: final report April 2013
The economic vitality and quality of life of many northern Wisconsin communities is closely associated with the ecological condition of the abundant water resources in the region. Climate change models predict warmer temperatures, changes to precipitation patterns, and increased evapotranspiration in the Great Lakes region. Recently (1950-2006), many regions of Wisconsin have experienced...
Authors
Michael Frederick Meyer, John F. Walker, Kevin P. Kenow, Paul W. Rasmussen, Paul J. Garrison, Paul R. Hanson, Randall Hunt
Approaches in highly parameterized inversion: TSPROC, a general time-series processor to assist in model calibration and result summarization
The TSPROC (Time Series PROCessor) computer software uses a simple scripting language to process and analyze time series. It was developed primarily to assist in the calibration of environmental models. The software is designed to perform calculations on time-series data commonly associated with surface-water models, including calculation of flow volumes, transformation by means of basic...
Authors
Stephen M. Westenbroek, John E. Doherty, John F. Walker, Victor A. Kelson, Randall Hunt, Timothy B. Cera
Watershed scale response to climate change--Black Earth Creek Basin, Wisconsin
General Circulation Model simulations of future climate through 2099 project a wide range of possible scenarios. To determine the sensitivity and potential effect of long-term climate change on the freshwater resources of the United States, the U.S. Geological Survey Global Change study, "An integrated watershed scale response to global change in selected basins across the United States"...
Authors
Randall Hunt, John F. Walker, Steven M. Westenbroek, Lauren Hay, Steven L. Markstrom
Watershed scale response to climate change--Trout Lake Basin, Wisconsin
General Circulation Model simulations of future climate through 2099 project a wide range of possible scenarios. To determine the sensitivity and potential effect of long-term climate change on the freshwater resources of the United States, the U.S. Geological Survey Global Change study, "An integrated watershed scale response to global change in selected basins across the United States"...
Authors
John F. Walker, Randall Hunt, Lauren Hay, Steven L. Markstrom
Integrated watershed-scale response to climate change for selected basins across the United States
A study by the U.S. Geological Survey (USGS) evaluated the hydrologic response to different projected carbon emission scenarios of the 21st century using a hydrologic simulation model. This study involved five major steps: (1) setup, calibrate and evaluated the Precipitation Runoff Modeling System (PRMS) model in 14 basins across the United States by local USGS personnel; (2) acquire...
Authors
Steven L. Markstrom, Lauren Hay, Christian D. Ward-Garrison, John Risley, William Battaglin, David M. Bjerklie, Katherine J. Chase, Daniel E. Christiansen, Robert W. Dudley, Randall Hunt, Kathryn M. Koczot, Mark C. Mastin, R. Steve Regan, Roland J. Viger, Kevin C. Vining, John F. Walker
Effects of best-management practices in Eagle and Joos Valley Creeks in the Waumandee Creek Priority Watershed, Wisconsin, 1990-2007
In many watersheds, nonpoint-source contamination is a major contributor to water-quality problems. In response to the recognition of the importance of nonpoint sources, the Wisconsin Nonpoint Source Water Pollution Abatement Program (Nonpoint Program) was enacted in 1978. This report summarizes the results of a study to assess the effectiveness of watershed-management practices for...
Authors
David J. Graczyk, John F. Walker, Roger T. Bannerman, Troy D. Rutter
Groundwater recharge in Wisconsin— Annual estimates for 1970–99 using streamflow data
The groundwater component of streamflow is important because it is indicative of the sustained flow of a stream during dry periods, is often of better quality, and has a smaller range of temperatures, than surface contributions to streamflow. All three of these characteristics are important to the health of aquatic life in a stream. If recharge to the aquifers is to be preserved or...
Authors
Warren A. Gebert, John F. Walker, Randall Hunt
Estimating 1970-99 average annual groundwater recharge in Wisconsin using streamflow data
Average annual recharge in Wisconsin for the period 1970-99 was estimated using streamflow data from U.S. Geological Survey continuous-record streamflow-gaging stations and partial-record sites. Partial-record sites have discharge measurements collected during low-flow conditions. The average annual base flow of a stream divided by the drainage area is a good approximation of the...
Authors
Warren A. Gebert, John F. Walker, James L. Kennedy
Characterizing climate-change impacts on the 1.5-yr flood flow in selected basins across the United States: a probabilistic approach
The U.S. Geological Survey Precipitation-Runoff Modeling System (PRMS) model was applied to basins in 14 different hydroclimatic regions to determine the sensitivity and variability of the freshwater resources of the United States in the face of current climate-change projections. Rather than attempting to choose a most likely scenario from the results of the Intergovernmental Panel on...
Authors
John F. Walker, Lauren Hay, Steven L. Markstrom, Michael D. Dettinger
Using a coupled groundwater/surface-water model to predict climate-change impacts to lakes in the Trout Lake Watershed, northern Wisconsin
A major focus of the U.S. Geological Survey’s Trout Lake Water, Energy, and Biogeochemical Budgets (WEBB) project is the development of a watershed model to allow predictions of hydrologic response to future conditions including land-use and climate change. The coupled groundwater/surface-water model GSFLOW was chosen for this purpose because it could easily incorporate an existing...
Authors
Randall Hunt, John F. Walker, Steven L. Markstrom, Lauren Hay, John E. Doherty
Next Generation Water Observing System: Illinois River Basin
The Next Generation Water Observing System provides high-fidelity, real-time data on water quantity, quality, and use to support modern water prediction and decision-support systems that are necessary for informing water operations on a daily basis and decision-making during water emergencies. The Illinois River Basin provides an opportunity to implement the NGWOS in a system challenged by an...
Flood frequency in Wisconsin
Flood-frequency estimates are required at many sites for bridge and culvert design, as well as for flood-plain management and flood-insurance studies. To estimate flood frequency at ungaged locations, a network of approximately 90 crest-stage gages and more than 200 past and current continuous-record gages are used to compute regional flood-frequency equations to estimate floods at ungaged sites.