David M Wolock, Ph.D.
David Wolock is a Supervisory Hydrologist with the USGS Water Resources Mission Area.
Science and Products
Filter Total Items: 13
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Sparrow modeling to understand water quality conditions in major regions of the United States: A featured collection introduction
No abstract available.
Authors
Stephen D. Preston, Richard B. Alexander, David M. Wolock
Digital hydrologic networks supporting applications related to spatially referenced regression modeling
Digital hydrologic networks depicting surface-water pathways and their associated drainage catchments provide a key component to hydrologic analysis and modeling. Collectively, they form common spatial units that can be used to frame the descriptions of aquatic and watershed processes. In addition, they provide the ability to simulate and route the movement of water and associated constituents thr
Authors
John W. Brakebill, David M. Wolock, Silvia Terziotti
Independent effects of temperature and precipitation on modeled runoff in the conterminous United States
A water‐balance model is used to simulate time series of water‐year runoff for 4 km × 4 km grid cells for the conterminous United States during the 1900–2008 period. Model outputs are used to examine the separate effects of precipitation and temperature on runoff variability. Overall, water‐year runoff has increased in the conterminous United States and precipitation has accounted for almost all o
Authors
Gregory J. McCabe, David M. Wolock
Century-scale variability in global annual runoff examined using a water balance model
A monthly water balance model (WB model) is used with CRUTS2.1 monthly temperature and precipitation data to generate time series of monthly runoff for all land areas of the globe for the period 1905 through 2002. Even though annual precipitation accounts for most of the temporal and spatial variability in annual runoff, increases in temperature have had an increasingly negative effect on annual r
Authors
G.J. McCabe, D. M. Wolock
Digital hydrologic networks supporting applications related to spatially referenced regression modeling
Digital hydrologic networks depicting surface‐water pathways and their associated drainage catchments provide a key component to hydrologic analysis and modeling. Collectively, they form common spatial units that can be used to frame the descriptions of aquatic and watershed processes. In addition, they provide the ability to simulate and route the movement of water and associated constituents thr
Authors
J. W. Brakebill, D. M. Wolock, S.E. Terziotti
Sparrow modeling to understand water-quality conditions in major regions of the United States: A featured collection introduction
No abstract available.
Authors
S. D. Preston, R. B. Alexander, D. M. Wolock
Alteration of streamflow magnitudes and potential ecological consequences: A multiregional assessment
Human impacts on watershed hydrology are widespread in the US, but the prevalence and severity of stream-flow alteration and its potential ecological consequences have not been quantified on a national scale. We assessed streamflow alteration at 2888 streamflow monitoring sites throughout the conterminous US. The magnitudes of mean annual (1980–2007) minimum and maximum streamflows were found to h
Authors
Daren Carlisle, David M. Wolock, Michael R. Meador
Streamflow of 2010--Water year summary
The maps and graph in this summary describe streamflow conditions for water-year 2010 (October 1, 2009 to September 30, 2010) in the context of the 81-year period 1930-2010, unless otherwise noted. The illustrations are based on observed data from the U.S. Geological Survey's (USGS) National Streamflow Information Program. The period 1930-2010 was used because prior to 1930, the number of streamga
Authors
Jian Xiaodong, David M. Wolock, Harry F. Lins, Steve Brady
Alteration of streamflow magnitudes and potential ecological consequences: A multiregional assessment
Human impacts on watershed hydrology are widespread in the US, but the prevalence and severity of stream‐flow alteration and its potential ecological consequences have not been quantified on a national scale. We assessed streamflow alteration at 2888 streamflow monitoring sites throughout the conterminous US. The magnitudes of mean annual (1980–2007) minimum and maximum streamflows were found to h
Authors
Daren Carlisle, David M. Wolock, Michael R. Meador
GAGES: A stream gage database for evaluating natural and alteredflow conditions in the conterminous United States
Stream flow is a controlling element in the ecology of rivers and streams. Knowledge of the natural flow regime facilitates the assessment of whether specific hydrologic attributes have been altered by humans in a particular stream and the establishment of specific goals for stream-flow restoration. Because most streams are ungaged or have been altered by human influences, characterizing the natur
Authors
James A. Falcone, Daren Carlisle, David M. Wolock, Michael R. Meador
Nitrate Loads and Concentrations in Surface-Water Base Flow and Shallow Groundwater for Selected Basins in the United States, Water Years 1990-2006
Hydrograph separation was used to determine the base-flow component of streamflow for 148 sites sampled as part of the National Water-Quality Assessment program. Sites in the Southwest and the Northwest tend to have base-flow index values greater than 0.5. Sites in the Midwest and the eastern portion of the Southern Plains generally have values less than 0.5. Base-flow index values for sites in th
Authors
Norman E. Spahr, Neil M. Dubrovsky, JoAnn M. Gronberg, O. Lehn Franke, David M. Wolock
Development and Application of Regression Models for Estimating Nutrient Concentrations in Streams of the Conterminous United States, 1992-2001
Data collected for the U.S. Geological Survey National Water-Quality Assessment program from 1992-2001 were used to investigate the relations between nutrient concentrations and nutrient sources, hydrology, and basin characteristics. Regression models were developed to estimate annual flow-weighted concentrations of total nitrogen and total phosphorus using explanatory variables derived from curre
Authors
Norman E. Spahr, David K. Mueller, David M. Wolock, Kerie J. Hitt, JoAnn M. Gronberg
Science and Products
Filter Total Items: 13
No Result Found
Filter Total Items: 129
Sparrow modeling to understand water quality conditions in major regions of the United States: A featured collection introduction
No abstract available.
Authors
Stephen D. Preston, Richard B. Alexander, David M. Wolock
Digital hydrologic networks supporting applications related to spatially referenced regression modeling
Digital hydrologic networks depicting surface-water pathways and their associated drainage catchments provide a key component to hydrologic analysis and modeling. Collectively, they form common spatial units that can be used to frame the descriptions of aquatic and watershed processes. In addition, they provide the ability to simulate and route the movement of water and associated constituents thr
Authors
John W. Brakebill, David M. Wolock, Silvia Terziotti
Independent effects of temperature and precipitation on modeled runoff in the conterminous United States
A water‐balance model is used to simulate time series of water‐year runoff for 4 km × 4 km grid cells for the conterminous United States during the 1900–2008 period. Model outputs are used to examine the separate effects of precipitation and temperature on runoff variability. Overall, water‐year runoff has increased in the conterminous United States and precipitation has accounted for almost all o
Authors
Gregory J. McCabe, David M. Wolock
Century-scale variability in global annual runoff examined using a water balance model
A monthly water balance model (WB model) is used with CRUTS2.1 monthly temperature and precipitation data to generate time series of monthly runoff for all land areas of the globe for the period 1905 through 2002. Even though annual precipitation accounts for most of the temporal and spatial variability in annual runoff, increases in temperature have had an increasingly negative effect on annual r
Authors
G.J. McCabe, D. M. Wolock
Digital hydrologic networks supporting applications related to spatially referenced regression modeling
Digital hydrologic networks depicting surface‐water pathways and their associated drainage catchments provide a key component to hydrologic analysis and modeling. Collectively, they form common spatial units that can be used to frame the descriptions of aquatic and watershed processes. In addition, they provide the ability to simulate and route the movement of water and associated constituents thr
Authors
J. W. Brakebill, D. M. Wolock, S.E. Terziotti
Sparrow modeling to understand water-quality conditions in major regions of the United States: A featured collection introduction
No abstract available.
Authors
S. D. Preston, R. B. Alexander, D. M. Wolock
Alteration of streamflow magnitudes and potential ecological consequences: A multiregional assessment
Human impacts on watershed hydrology are widespread in the US, but the prevalence and severity of stream-flow alteration and its potential ecological consequences have not been quantified on a national scale. We assessed streamflow alteration at 2888 streamflow monitoring sites throughout the conterminous US. The magnitudes of mean annual (1980–2007) minimum and maximum streamflows were found to h
Authors
Daren Carlisle, David M. Wolock, Michael R. Meador
Streamflow of 2010--Water year summary
The maps and graph in this summary describe streamflow conditions for water-year 2010 (October 1, 2009 to September 30, 2010) in the context of the 81-year period 1930-2010, unless otherwise noted. The illustrations are based on observed data from the U.S. Geological Survey's (USGS) National Streamflow Information Program. The period 1930-2010 was used because prior to 1930, the number of streamga
Authors
Jian Xiaodong, David M. Wolock, Harry F. Lins, Steve Brady
Alteration of streamflow magnitudes and potential ecological consequences: A multiregional assessment
Human impacts on watershed hydrology are widespread in the US, but the prevalence and severity of stream‐flow alteration and its potential ecological consequences have not been quantified on a national scale. We assessed streamflow alteration at 2888 streamflow monitoring sites throughout the conterminous US. The magnitudes of mean annual (1980–2007) minimum and maximum streamflows were found to h
Authors
Daren Carlisle, David M. Wolock, Michael R. Meador
GAGES: A stream gage database for evaluating natural and alteredflow conditions in the conterminous United States
Stream flow is a controlling element in the ecology of rivers and streams. Knowledge of the natural flow regime facilitates the assessment of whether specific hydrologic attributes have been altered by humans in a particular stream and the establishment of specific goals for stream-flow restoration. Because most streams are ungaged or have been altered by human influences, characterizing the natur
Authors
James A. Falcone, Daren Carlisle, David M. Wolock, Michael R. Meador
Nitrate Loads and Concentrations in Surface-Water Base Flow and Shallow Groundwater for Selected Basins in the United States, Water Years 1990-2006
Hydrograph separation was used to determine the base-flow component of streamflow for 148 sites sampled as part of the National Water-Quality Assessment program. Sites in the Southwest and the Northwest tend to have base-flow index values greater than 0.5. Sites in the Midwest and the eastern portion of the Southern Plains generally have values less than 0.5. Base-flow index values for sites in th
Authors
Norman E. Spahr, Neil M. Dubrovsky, JoAnn M. Gronberg, O. Lehn Franke, David M. Wolock
Development and Application of Regression Models for Estimating Nutrient Concentrations in Streams of the Conterminous United States, 1992-2001
Data collected for the U.S. Geological Survey National Water-Quality Assessment program from 1992-2001 were used to investigate the relations between nutrient concentrations and nutrient sources, hydrology, and basin characteristics. Regression models were developed to estimate annual flow-weighted concentrations of total nitrogen and total phosphorus using explanatory variables derived from curre
Authors
Norman E. Spahr, David K. Mueller, David M. Wolock, Kerie J. Hitt, JoAnn M. Gronberg