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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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
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
Effects of climatic change on the Thornthwaite moisture index
The Thornthwaite moisture index is a useful indicator of the supply of water (precipitation) in an area relative to the demand for water under prevailing climatic conditions (potential evapotranspiration). This study examines the effects of changes in climate (temperature and precipitation) on the Thornthwaite moisture index in the conterminous United States. Estimates of changes in mean annual te
Authors
Gregory J. McCabe, David M. Wolock, Lauren E. Hay, Mark A. Ayers
Topographic effects on flow path and surface water chemistry of the Llyn Brianne catchments in Wales
Topographic shape is a watershed attribute thought to influence the flow path followed by water as it traverses a catchment. Flow path, in turn, may affect the chemical composition of surface waters. Topography is quantified in the hydrological model TOPMODEL as the relative frequency distribution of the index ln( a tanB), where a is the upslope area per unit contour that drains past a point and t
Authors
D. M. Wolock, G.M. Hornberger, T.J. Musgrove
Simulated effects of climatic change on runoff and drought in the Delaware River Basin
Various projection of climatic change were applied to watershed models of the Delaware River basin. Simulations indicate that a warming could reduce annual runoff by as much as 25 percent if current precipitation patterns continue. Simulations indicate that the largest changes in basin drought are in response to relatively small changes in precipitation. Basin drought was less sensitive to increas
Authors
Mark A. Ayers, Gary D. Tasker, David M. Wolock, Gregory J. McCabe, Lauren E. Hay
Extraction of terrain features from digital elevation models
Digital elevation models (DEMs) are being used to determine variable inputs for hydrologic models in the Delaware River basin. Recently developed software for analysis of DEMs has been applied to watershed and streamline delineation. The results compare favorably with similar delineations taken from topographic maps. Additionally, output from this software has been used to extract other hydrologic
Authors
Curtis V. Price, David M. Wolock, Mark A. Ayers
The relationship of catchment topography and soil hydraulic characteristics to lake alkalinity in the northeastern United States
We undertook the task of determining whether base flow alkalinity of surface waters in the northeastern United States is related to indices of soil contact time and flow path partitioning that are derived from topographic and soils information. The influence of topography and soils on catchment hydrology has been incorporated previously in the variable source area model TOPMODEL as the relative fr
Authors
D. M. Wolock, G.M. Hornberger, K.J. Beven, W.G. Campbell
Simulation of precipitation by weather-type analysis
A new approach that uses weather-type analysis as a basis for stochastic precipitation modeling was developed and tested for Philadelphia, Pennsylvania. The weather types permit the identification of weather conditions associated with varying frequencies, intensities, and amounts of precipitation. Weather-type frequencies were used to stochastically simulate precipitation for Philadelphia and to p
Authors
G. J. McCabe, L.E. Hay, L.S. Kalkstein, M. A. Ayers, D. M. Wolock
Effect of climate change on watershed runoff
This paper examines forecasts of changes in watershed runoff in the Delaware River basin that result from a range of predicted effects of increased atmospheric carbon dioxide (CO2) on future precipitation, temperature, and stomatal resistance of plants. A deterministic hydrologic model, TOPMODEL, was driven with stochastic inputs of temperature and precipitation to derive the forecasts. Results in
Authors
D. M. Wolock, M. A. Ayers, L.E. Hay, G. J. McCabe
Science and Products
Filter Total Items: 13
No Result Found
Filter Total Items: 129
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
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
Effects of climatic change on the Thornthwaite moisture index
The Thornthwaite moisture index is a useful indicator of the supply of water (precipitation) in an area relative to the demand for water under prevailing climatic conditions (potential evapotranspiration). This study examines the effects of changes in climate (temperature and precipitation) on the Thornthwaite moisture index in the conterminous United States. Estimates of changes in mean annual te
Authors
Gregory J. McCabe, David M. Wolock, Lauren E. Hay, Mark A. Ayers
Topographic effects on flow path and surface water chemistry of the Llyn Brianne catchments in Wales
Topographic shape is a watershed attribute thought to influence the flow path followed by water as it traverses a catchment. Flow path, in turn, may affect the chemical composition of surface waters. Topography is quantified in the hydrological model TOPMODEL as the relative frequency distribution of the index ln( a tanB), where a is the upslope area per unit contour that drains past a point and t
Authors
D. M. Wolock, G.M. Hornberger, T.J. Musgrove
Simulated effects of climatic change on runoff and drought in the Delaware River Basin
Various projection of climatic change were applied to watershed models of the Delaware River basin. Simulations indicate that a warming could reduce annual runoff by as much as 25 percent if current precipitation patterns continue. Simulations indicate that the largest changes in basin drought are in response to relatively small changes in precipitation. Basin drought was less sensitive to increas
Authors
Mark A. Ayers, Gary D. Tasker, David M. Wolock, Gregory J. McCabe, Lauren E. Hay
Extraction of terrain features from digital elevation models
Digital elevation models (DEMs) are being used to determine variable inputs for hydrologic models in the Delaware River basin. Recently developed software for analysis of DEMs has been applied to watershed and streamline delineation. The results compare favorably with similar delineations taken from topographic maps. Additionally, output from this software has been used to extract other hydrologic
Authors
Curtis V. Price, David M. Wolock, Mark A. Ayers
The relationship of catchment topography and soil hydraulic characteristics to lake alkalinity in the northeastern United States
We undertook the task of determining whether base flow alkalinity of surface waters in the northeastern United States is related to indices of soil contact time and flow path partitioning that are derived from topographic and soils information. The influence of topography and soils on catchment hydrology has been incorporated previously in the variable source area model TOPMODEL as the relative fr
Authors
D. M. Wolock, G.M. Hornberger, K.J. Beven, W.G. Campbell
Simulation of precipitation by weather-type analysis
A new approach that uses weather-type analysis as a basis for stochastic precipitation modeling was developed and tested for Philadelphia, Pennsylvania. The weather types permit the identification of weather conditions associated with varying frequencies, intensities, and amounts of precipitation. Weather-type frequencies were used to stochastically simulate precipitation for Philadelphia and to p
Authors
G. J. McCabe, L.E. Hay, L.S. Kalkstein, M. A. Ayers, D. M. Wolock
Effect of climate change on watershed runoff
This paper examines forecasts of changes in watershed runoff in the Delaware River basin that result from a range of predicted effects of increased atmospheric carbon dioxide (CO2) on future precipitation, temperature, and stomatal resistance of plants. A deterministic hydrologic model, TOPMODEL, was driven with stochastic inputs of temperature and precipitation to derive the forecasts. Results in
Authors
D. M. Wolock, M. A. Ayers, L.E. Hay, G. J. McCabe