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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Filter Total Items: 127
Combining digital spatial data with hydrologic measurements to interpret controls of stream chemistry in large watersheds
No abstract available.
Authors
Yvonne H. Baevsky, Gregory B. Lawrence, David M. Wolock, Douglas A. Burns, Peter S. Murdoch
Effects of basin size on low-flow stream chemistry and subsurface contact time in the neversink river watershed, New York
The effects of basin size on low-flow stream chemistry and subsurface contact time were examined for a part of the Neversink River watershed in southern New York State. Acid neutralizing capacity (ANC), the sum of base cation concentrations (SBC), pH and concentrations of total aluminum (Al), dissolved organic carbon (DOC) and silicon (Si) were measured during low stream flow at the outlets of nes
Authors
D. M. Wolock, J. Fan, G. B. Lawrence
Climate change and the detection of trends in annual runoff
This study examines the statistical likelihood of detecting a trend in annual runoff given an assumed change in mean annual runoff, the underlying year-to-year variability in runoff, and serial correlation of annual runoff. Means, standard deviations, and lag-1 serial correlations of annual runoff were computed for 585 stream gages in the conterminous United States, and these statistics were used
Authors
G. J. McCabe, D. M. Wolock
Scale and modeling issues in water resources planning
Resource planners and managers interested in utilizing climate model output as part of their operational activities immediately confront the dilemma of scale discordance. Their functional responsibilities cover relatively small geographical areas and necessarily require data of relatively high spatial resolution. Climate models cover a large geographical, i.e. global, domain and produce data at co
Authors
H.F. Lins, D. M. Wolock, G.J. McCabe
STATSGO soil characteristics for the conterminous United States
This digital data release consists of an ARC/INFO grid and associated
INFO tables. The grid is called MUID and has STATSGO (U.S. Department
of Agriculture, 1994) soil mapping unit identifiers gridded on a
1-kilometer resolution for the conterminous United States. The INFO
tables have soil characteristics data in them. The ITEMS in the tables
are weighted average values for several soil characteris
Authors
David M. Wolock
Sensitivity of water resources in the Delaware River basin to climate variability and change
Because of the greenhouse effect, projected increases in atmospheric carbon dioxide levels might cause global warming, which in turn could result in changes in precipitation patterns and evapotranspiration and in increases in sea level. This report describes the greenhouse effect; discusses the problems and uncertainties associated with the detection, prediction, and effects of climate change; and
Authors
Mark A. Ayers, David M. Wolock, Gregory J. McCabe, Lauren E. Hay, Gary D. Tasker
Simulating the variable-source-area concept of streamflow generation with the watershed model TOPMODEL
This report describes TOPMODEL, which is a physically based watershed model that simulates the variable-source-area concept of streamflow generation. The report describes the theoretical background, model equations, methods to determine parameter values, Fortran computer code, and an example interactive simulation. Using TOPMODEL requires specification of soils and topographic parameters, watershe
Authors
D. M. Wolock
Sensitivity of water resources in the Delaware River basin to climate variability and change
Because of the "greenhouse effect," projected increases in atmospheric carbon dioxide levels might cause global warming, which in turn could result in changes in precipitation patterns and evapotranspiration and in increases in sea level. This report describes the greenhouse effect; discusses the problems and uncertainties associated with the detection, prediction, and effects of climatic change,
Authors
Mark A. Ayers, David M. Wolock, Gregory J. McCabe, Lauren E. Hay, Gary D. Tasker
Use of weather types to disaggregate general circulation model predictions
General circulation models (GCMs) simulate climatic conditions with a grid cell resolution on the order of 100,000 km2. This resolution is inadequate to assess the effects of climatic change on water resources at a regional scale. A method has been developed that uses weather-type analysis as a tool to spatially disaggregate GCM predictions to make them useful for water resource studies. The metho
Authors
L.E. Hay, G. J. McCabe, D. M. Wolock, M. A. Ayers
Effects of climatic change and climatic variability on the Thornthwaite moisture index in the Delaware River basin
The Thornthwaite moisture index is useful as an indicator of the supply of water in an area relative to the demand under prevailing climatic conditions. This study examines the effects of long-term changes in climate (temperature and precipitation) on the Thornthwaite moisture index in the Delaware River basin. Temperature and precipitation estimates for doubled-CO2 conditions derived from three g
Authors
G. J. McCabe, D. M. Wolock
Detectability of the effects of a hypothetical temperature increase on the Thornthwaite moisture index
Climatic changes that result from increasing concentrations of atmospheric carbon dioxide may affect the availability of water for vegetation, groundwater recharge, runoff, and human consumption. Most studies of the effects of climatic change on water resources focus on changes in mean characteristics of hydrologic variables and do not consider the effects of these changes amid natural climatic va
Authors
G. J. McCabe, D. M. Wolock
Uncertainty in climate change and drought
A series of projections of climate change were applied to a watershed model of the Delaware River basin to identify sources of uncertainty in predicting effects of climate change on drought in the basin as defined by New York City reservoir contents. The watershed model is a calibrated, monthly time-step water-balance model that incorporates the operation of reservoirs and diversion canals, and ac
Authors
Gregory J. McCabe, David M. Wolock, Gary D. Tasker, Mark A. Ayers
Science and Products
Filter Total Items: 13
No Result Found
Filter Total Items: 127
Combining digital spatial data with hydrologic measurements to interpret controls of stream chemistry in large watersheds
No abstract available.
Authors
Yvonne H. Baevsky, Gregory B. Lawrence, David M. Wolock, Douglas A. Burns, Peter S. Murdoch
Effects of basin size on low-flow stream chemistry and subsurface contact time in the neversink river watershed, New York
The effects of basin size on low-flow stream chemistry and subsurface contact time were examined for a part of the Neversink River watershed in southern New York State. Acid neutralizing capacity (ANC), the sum of base cation concentrations (SBC), pH and concentrations of total aluminum (Al), dissolved organic carbon (DOC) and silicon (Si) were measured during low stream flow at the outlets of nes
Authors
D. M. Wolock, J. Fan, G. B. Lawrence
Climate change and the detection of trends in annual runoff
This study examines the statistical likelihood of detecting a trend in annual runoff given an assumed change in mean annual runoff, the underlying year-to-year variability in runoff, and serial correlation of annual runoff. Means, standard deviations, and lag-1 serial correlations of annual runoff were computed for 585 stream gages in the conterminous United States, and these statistics were used
Authors
G. J. McCabe, D. M. Wolock
Scale and modeling issues in water resources planning
Resource planners and managers interested in utilizing climate model output as part of their operational activities immediately confront the dilemma of scale discordance. Their functional responsibilities cover relatively small geographical areas and necessarily require data of relatively high spatial resolution. Climate models cover a large geographical, i.e. global, domain and produce data at co
Authors
H.F. Lins, D. M. Wolock, G.J. McCabe
STATSGO soil characteristics for the conterminous United States
This digital data release consists of an ARC/INFO grid and associated
INFO tables. The grid is called MUID and has STATSGO (U.S. Department
of Agriculture, 1994) soil mapping unit identifiers gridded on a
1-kilometer resolution for the conterminous United States. The INFO
tables have soil characteristics data in them. The ITEMS in the tables
are weighted average values for several soil characteris
Authors
David M. Wolock
Sensitivity of water resources in the Delaware River basin to climate variability and change
Because of the greenhouse effect, projected increases in atmospheric carbon dioxide levels might cause global warming, which in turn could result in changes in precipitation patterns and evapotranspiration and in increases in sea level. This report describes the greenhouse effect; discusses the problems and uncertainties associated with the detection, prediction, and effects of climate change; and
Authors
Mark A. Ayers, David M. Wolock, Gregory J. McCabe, Lauren E. Hay, Gary D. Tasker
Simulating the variable-source-area concept of streamflow generation with the watershed model TOPMODEL
This report describes TOPMODEL, which is a physically based watershed model that simulates the variable-source-area concept of streamflow generation. The report describes the theoretical background, model equations, methods to determine parameter values, Fortran computer code, and an example interactive simulation. Using TOPMODEL requires specification of soils and topographic parameters, watershe
Authors
D. M. Wolock
Sensitivity of water resources in the Delaware River basin to climate variability and change
Because of the "greenhouse effect," projected increases in atmospheric carbon dioxide levels might cause global warming, which in turn could result in changes in precipitation patterns and evapotranspiration and in increases in sea level. This report describes the greenhouse effect; discusses the problems and uncertainties associated with the detection, prediction, and effects of climatic change,
Authors
Mark A. Ayers, David M. Wolock, Gregory J. McCabe, Lauren E. Hay, Gary D. Tasker
Use of weather types to disaggregate general circulation model predictions
General circulation models (GCMs) simulate climatic conditions with a grid cell resolution on the order of 100,000 km2. This resolution is inadequate to assess the effects of climatic change on water resources at a regional scale. A method has been developed that uses weather-type analysis as a tool to spatially disaggregate GCM predictions to make them useful for water resource studies. The metho
Authors
L.E. Hay, G. J. McCabe, D. M. Wolock, M. A. Ayers
Effects of climatic change and climatic variability on the Thornthwaite moisture index in the Delaware River basin
The Thornthwaite moisture index is useful as an indicator of the supply of water in an area relative to the demand under prevailing climatic conditions. This study examines the effects of long-term changes in climate (temperature and precipitation) on the Thornthwaite moisture index in the Delaware River basin. Temperature and precipitation estimates for doubled-CO2 conditions derived from three g
Authors
G. J. McCabe, D. M. Wolock
Detectability of the effects of a hypothetical temperature increase on the Thornthwaite moisture index
Climatic changes that result from increasing concentrations of atmospheric carbon dioxide may affect the availability of water for vegetation, groundwater recharge, runoff, and human consumption. Most studies of the effects of climatic change on water resources focus on changes in mean characteristics of hydrologic variables and do not consider the effects of these changes amid natural climatic va
Authors
G. J. McCabe, D. M. Wolock
Uncertainty in climate change and drought
A series of projections of climate change were applied to a watershed model of the Delaware River basin to identify sources of uncertainty in predicting effects of climate change on drought in the basin as defined by New York City reservoir contents. The watershed model is a calibrated, monthly time-step water-balance model that incorporates the operation of reservoirs and diversion canals, and ac
Authors
Gregory J. McCabe, David M. Wolock, Gary D. Tasker, Mark A. Ayers