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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Streamflow of 2009--Water year summary
The maps and graph in this summary describe streamflow conditions for water-year 2009 (October 1, 2008 to September 30, 2009) in the context of the 80-year period 1930-2009, unless otherwise noted. The illustrations are based on observed data from the U.S. Geological Survey's National Streamflow Information Program. The period 1930-2009 was used because prior to 1930, the number of streamgages was
Authors
Jian Xiaodong, David M. Wolock, Harry F. Lins, Steve Brady
Long-term variability in Northern Hemisphere snow cover and associations with warmer winters
A monthly snow accumulation and melt model is used with gridded monthly temperature and precipitation data for the Northern Hemisphere to generate time series of March snow-covered area (SCA) for the period 1905 through 2002. The time series of estimated SCA for March is verified by comparison with previously published time series of SCA for the Northern Hemisphere. The time series of estimated No
Authors
Gregory J. McCabe, David M. Wolock
Long-term variability in Northern Hemisphere snow cover and associations with warmer winters
A monthly snow accumulation and melt model is used with gridded monthly temperature and precipitation data for the Northern Hemisphere to generate time series of March snow-covered area (SCA) for the period 1905 through 2002. The time series of estimated SCA for March is verified by comparison with previously published time series of SCA for the Northern Hemisphere. The time series of estimated No
Authors
G.J. McCabe, D. M. Wolock
Identifying Hydrologic Processes in Agricultural Watersheds Using Precipitation-Runoff Models
Understanding the fate and transport of agricultural chemicals applied to agricultural fields will assist in designing the most effective strategies to prevent water-quality impairments. At a watershed scale, the processes controlling the fate and transport of agricultural chemicals are generally understood only conceptually. To examine the applicability of conceptual models to the processes actua
Authors
Joshua I. Linard, David M. Wolock, Richard M. T. Webb, Michael Wieczorek
Regression models for explaining and predicting concentrations of organochlorine pesticides in fish from streams in the United States
Empirical regression models were developed for estimating concentrations of dieldrin, total chlordane, and total DDT in whole fish from U.S. streams. Models were based on pesticide concentrations measured in whole fish at 648 stream sites nationwide (1992-2001) as part of the U.S. Geological Survey's National Water Quality Assessment Program. Explanatory variables included fish lipid content, esti
Authors
Lisa H. Nowell, Charles G. Crawford, Robert J. Gilliom, Naomi Nakagaki, Wesley W. Stone, Gail Thelin, David M. Wolock
Identifying pathways and processes affecting nitrate and orthophosphate inputs to streams in agricultural watersheds
Understanding nutrient pathways to streams will improve nutrient management strategies and estimates of the time lag between when changes in land use practices occur and when water quality effects that result from these changes are observed. Nitrate and orthophosphate (OP) concentrations in several environmental compartments were examined in watersheds having a range of base flow index (BFI) value
Authors
A. J. Tesoriero, J.H. Duff, D. M. Wolock, N.E. Spahr, J.E. Almendinger
Predicting the natural flow regime: Models for assessing hydrological alteration in streams
Understanding the extent to which natural streamflow characteristics have been altered is an important consideration for ecological assessments of streams. Assessing hydrologic condition requires that we quantify the attributes of the flow regime that would be expected in the absence of anthropogenic modifications. The objective of this study was to evaluate whether selected streamflow characteris
Authors
D.M. Carlisle, J. Falcone, D. M. Wolock, M. R. Meador, R.H. Norris
Streamflow of 2008--Water year summary
The maps and graphs appearing in this summary describe streamflow conditions for water-year 2008 (October 1, 2007 to September 30, 2008) in the context of the 79-year period 1930-2008, unless otherwise noted. The illustrations are based on observed data from the U.S. Geological Survey's (USGS) National Streamflow Information Program. The period 1930-2008 was used because prior to 1930, the number
Authors
Jian Xiaodong, David M. Wolock, Harry F. Lins, Steve Brady
Recent declines in western U.S. snowpack in the context of twentieth-century climate variability
A monthly snow accumulation and melt model was used with monthly Precipitation-elevation Regressions on Independent Slopes Model (PRISM) temperature and precipitation data to generate time series of 1 April snow water equivalent (SWE) for 1900 through 2008 in the western United States. Averaged across the western United States, SWE generally was higher than long-term (1900–2008) average conditions
Authors
Gregory J. McCabe, David M. Wolock
Hydrologic droughts in Kansas— Are they becoming worse?
Multi-year droughts have been a recurrent feature of the climate and hydrology of Kansas since at least the 1930s. Streamflow records collected by the U.S. Geological Survey (USGS) indicate that water years 2000 to 2006 (October 1, 1999, through September 30, 2006) represent the sixth hydrologic drought during the past eight decades, and that corresponding streamflow levels in some parts of Kansas
Authors
James E. Putnam, Charles A. Perry, David M. Wolock
Streamflow of 2007--Water year summary
The maps and graphs appearing in this summary describe streamflow conditions for water-year 2007 (October 1, 2006 to September 30, 2007) in the context of the 78-year period 1930-2007, unless otherwise noted. The illustrations are based on observed data from the U.S. Geological Survey's (USGS) National Streamflow Information Program. The period 1930-2007 was used because prior to 1930, the number
Authors
Jian Xiaodong, David M. Wolock, Harry F. Lins
Joint variability of global runoff and global sea surface temperatures
Global land surface runoff and sea surface temperatures (SST) are analyzed to identify the primary modes of variability of these hydroclimatic data for the period 1905-2002. A monthly water-balance model first is used with global monthly temperature and precipitation data to compute time series of annual gridded runoff for the analysis period. The annual runoff time series data are combined with g
Authors
G.J. McCabe, D. M. Wolock
Science and Products
Filter Total Items: 13
No Result Found
Filter Total Items: 129
Streamflow of 2009--Water year summary
The maps and graph in this summary describe streamflow conditions for water-year 2009 (October 1, 2008 to September 30, 2009) in the context of the 80-year period 1930-2009, unless otherwise noted. The illustrations are based on observed data from the U.S. Geological Survey's National Streamflow Information Program. The period 1930-2009 was used because prior to 1930, the number of streamgages was
Authors
Jian Xiaodong, David M. Wolock, Harry F. Lins, Steve Brady
Long-term variability in Northern Hemisphere snow cover and associations with warmer winters
A monthly snow accumulation and melt model is used with gridded monthly temperature and precipitation data for the Northern Hemisphere to generate time series of March snow-covered area (SCA) for the period 1905 through 2002. The time series of estimated SCA for March is verified by comparison with previously published time series of SCA for the Northern Hemisphere. The time series of estimated No
Authors
Gregory J. McCabe, David M. Wolock
Long-term variability in Northern Hemisphere snow cover and associations with warmer winters
A monthly snow accumulation and melt model is used with gridded monthly temperature and precipitation data for the Northern Hemisphere to generate time series of March snow-covered area (SCA) for the period 1905 through 2002. The time series of estimated SCA for March is verified by comparison with previously published time series of SCA for the Northern Hemisphere. The time series of estimated No
Authors
G.J. McCabe, D. M. Wolock
Identifying Hydrologic Processes in Agricultural Watersheds Using Precipitation-Runoff Models
Understanding the fate and transport of agricultural chemicals applied to agricultural fields will assist in designing the most effective strategies to prevent water-quality impairments. At a watershed scale, the processes controlling the fate and transport of agricultural chemicals are generally understood only conceptually. To examine the applicability of conceptual models to the processes actua
Authors
Joshua I. Linard, David M. Wolock, Richard M. T. Webb, Michael Wieczorek
Regression models for explaining and predicting concentrations of organochlorine pesticides in fish from streams in the United States
Empirical regression models were developed for estimating concentrations of dieldrin, total chlordane, and total DDT in whole fish from U.S. streams. Models were based on pesticide concentrations measured in whole fish at 648 stream sites nationwide (1992-2001) as part of the U.S. Geological Survey's National Water Quality Assessment Program. Explanatory variables included fish lipid content, esti
Authors
Lisa H. Nowell, Charles G. Crawford, Robert J. Gilliom, Naomi Nakagaki, Wesley W. Stone, Gail Thelin, David M. Wolock
Identifying pathways and processes affecting nitrate and orthophosphate inputs to streams in agricultural watersheds
Understanding nutrient pathways to streams will improve nutrient management strategies and estimates of the time lag between when changes in land use practices occur and when water quality effects that result from these changes are observed. Nitrate and orthophosphate (OP) concentrations in several environmental compartments were examined in watersheds having a range of base flow index (BFI) value
Authors
A. J. Tesoriero, J.H. Duff, D. M. Wolock, N.E. Spahr, J.E. Almendinger
Predicting the natural flow regime: Models for assessing hydrological alteration in streams
Understanding the extent to which natural streamflow characteristics have been altered is an important consideration for ecological assessments of streams. Assessing hydrologic condition requires that we quantify the attributes of the flow regime that would be expected in the absence of anthropogenic modifications. The objective of this study was to evaluate whether selected streamflow characteris
Authors
D.M. Carlisle, J. Falcone, D. M. Wolock, M. R. Meador, R.H. Norris
Streamflow of 2008--Water year summary
The maps and graphs appearing in this summary describe streamflow conditions for water-year 2008 (October 1, 2007 to September 30, 2008) in the context of the 79-year period 1930-2008, unless otherwise noted. The illustrations are based on observed data from the U.S. Geological Survey's (USGS) National Streamflow Information Program. The period 1930-2008 was used because prior to 1930, the number
Authors
Jian Xiaodong, David M. Wolock, Harry F. Lins, Steve Brady
Recent declines in western U.S. snowpack in the context of twentieth-century climate variability
A monthly snow accumulation and melt model was used with monthly Precipitation-elevation Regressions on Independent Slopes Model (PRISM) temperature and precipitation data to generate time series of 1 April snow water equivalent (SWE) for 1900 through 2008 in the western United States. Averaged across the western United States, SWE generally was higher than long-term (1900–2008) average conditions
Authors
Gregory J. McCabe, David M. Wolock
Hydrologic droughts in Kansas— Are they becoming worse?
Multi-year droughts have been a recurrent feature of the climate and hydrology of Kansas since at least the 1930s. Streamflow records collected by the U.S. Geological Survey (USGS) indicate that water years 2000 to 2006 (October 1, 1999, through September 30, 2006) represent the sixth hydrologic drought during the past eight decades, and that corresponding streamflow levels in some parts of Kansas
Authors
James E. Putnam, Charles A. Perry, David M. Wolock
Streamflow of 2007--Water year summary
The maps and graphs appearing in this summary describe streamflow conditions for water-year 2007 (October 1, 2006 to September 30, 2007) in the context of the 78-year period 1930-2007, unless otherwise noted. The illustrations are based on observed data from the U.S. Geological Survey's (USGS) National Streamflow Information Program. The period 1930-2007 was used because prior to 1930, the number
Authors
Jian Xiaodong, David M. Wolock, Harry F. Lins
Joint variability of global runoff and global sea surface temperatures
Global land surface runoff and sea surface temperatures (SST) are analyzed to identify the primary modes of variability of these hydroclimatic data for the period 1905-2002. A monthly water-balance model first is used with global monthly temperature and precipitation data to compute time series of annual gridded runoff for the analysis period. The annual runoff time series data are combined with g
Authors
G.J. McCabe, D. M. Wolock