John F Walker (Former Employee)
Science and Products
Filter Total Items: 42
Integrated watershed-scale response to climate change for selected basins across the United States 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 E. Hay, D. Christian Ward-Garrison, John C. Risley, William A. Battaglin, David M. Bjerklie, Katherine J. Chase, Daniel E. Christiansen, Robert W. Dudley, Randall J. Hunt, Kathryn M. Koczot, Mark C. Mastin, R. Steven 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 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 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 J. Hunt
Estimating 1970-99 average annual groundwater recharge in Wisconsin using streamflow data 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 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 E. 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 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 J. Hunt, John F. Walker, Steven L. Markstrom, Lauren E. Hay, John Doherty
Science and Products
Filter Total Items: 42
Integrated watershed-scale response to climate change for selected basins across the United States 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 E. Hay, D. Christian Ward-Garrison, John C. Risley, William A. Battaglin, David M. Bjerklie, Katherine J. Chase, Daniel E. Christiansen, Robert W. Dudley, Randall J. Hunt, Kathryn M. Koczot, Mark C. Mastin, R. Steven 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 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 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 J. Hunt
Estimating 1970-99 average annual groundwater recharge in Wisconsin using streamflow data 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 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 E. 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 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 J. Hunt, John F. Walker, Steven L. Markstrom, Lauren E. Hay, John Doherty