David W Clow (Former Employee)
Science and Products
Filter Total Items: 67
Effects of backpacker use, pack stock trail use, and pack stock grazing on water-quality indicators, including nutrients, E. coli, hormones, and pharmaceuticals, in Yosemite National Park, USA
We investigated how visitor-use affects water quality in wilderness in Yosemite National Park. During the summers of 2012–2014, we collected and analyzed surface-water samples for water-quality indicators, including fecal indicator bacteria Escherichia coli, nutrients (nitrogen, phosphorus, carbon), suspended sediment concentration, pharmaceuticals, and hormones. Samples were collected upstream an
Authors
Harrison Forrester, David W. Clow, James W. Roche, Alan Heyvaert, William A. Battaglin
Inland waters and their role in the carbon cycle of Alaska
The magnitude of Alaska (AK) inland waters carbon (C) fluxes is likely to change in the future due to amplified climate warming impacts on the hydrology and biogeochemical processes in high latitude regions. Although current estimates of major aquatic C fluxes represent an essential baseline against which future change can be compared, a comprehensive assessment for AK has not yet been completed.
Authors
Sarah M. Stackpoole, David E. Butman, David W. Clow, Kristine L. Verdin, Benjamin V. Gaglioti, Hélène Genet, Robert G. Striegl
Spatial and temporal patterns of dissolved organic matter quantity and quality in the Mississippi River Basin, 1997–2013
Recent studies have found insignificant or decreasing trends in time-series dissolved organic carbon (DOC) datasets, questioning the assumption that long-term DOC concentrations in surface waters are increasing in response to anthropogenic forcing, including climate change, land use, and atmospheric acid deposition. We used the weighted regressions on time, discharge, and season (WRTDS) model to e
Authors
Sarah M. Stackpoole, Edward G. Stets, David W. Clow, Douglas A. Burns, George R. Aiken, Brent T. Aulenbach, Irena F. Creed, Robert M. Hirsch, Hjalmar Laudon, Brian Pellerin, Robert G. Striegl
Increasing aeolian dust deposition to snowpacks in the Rocky Mountains inferred from snowpack, wet deposition, and aerosol chemistry
Mountain snowpacks are a vital natural resource for ∼1.5 billion people in the northern Hemisphere, helping to meet human and ecological demand for water in excess of that provided by summer rain. Springtime warming and aeolian dust deposition accelerate snowmelt, increasing the risk of water shortages during late summer, when demand is greatest. While climate networks provide data that can be use
Authors
David W. Clow, Mark W. Williams, Paul F. Schuster
Comparison of methods for quantifying surface sublimation over seasonally snow-covered terrain
Snow sublimation can be an important component of the snow-cover mass balance, and there is considerable interest in quantifying the role of this process within the water and energy balance of snow-covered regions. In recent years, robust eddy covariance (EC) instrumentation has been used to quantify snow sublimation over snow-covered surfaces in complex mountainous terrain. However, EC can be cha
Authors
Graham A. Sexstone, David W. Clow, David I. Stannard, Steven R. Fassnacht
Numerical experiments to explain multiscale hydrological responses to mountain pine beetle tree mortality in a headwater watershed
The effects of mountain pine beetle (MPB)-induced tree mortality on a headwater hydrologic system were investigated using an integrated physical modeling framework with a high-resolution computational grid. Simulations of MPB-affected and unaffected conditions, each with identical atmospheric forcing for a normal water year, were compared at multiple scales to evaluate the effects of scale on MPB-
Authors
Colin A. Penn, Lindsay A. Bearup, Reed M. Maxwell, David W. Clow
Aquatic carbon cycling in the conterminous United States and implications for terrestrial carbon accounting
Inland water ecosystems dynamically process, transport, and sequester carbon. However, the transport of carbon through aquatic environments has not been quantitatively integrated in the context of terrestrial ecosystems. Here, we present the first integrated assessment, to our knowledge, of freshwater carbon fluxes for the conterminous United States, where 106 (range: 71–149) teragrams of carbon p
Authors
David Butman, Sarah M. Stackpoole, Edward G. Stets, Cory P. McDonald, David W. Clow, Robert G. Striegl
Water-quality response to a high-elevation wildfire in the Colorado Front Range
Water quality of the Big Thompson River in the Front Range of Colorado was studied for 2 years following a high‐elevation wildfire that started in October 2012 and burned 15% of the watershed. A combination of fixed‐interval sampling and continuous water‐quality monitors was used to examine the timing and magnitude of water‐quality changes caused by the wildfire. Prefire water quality was well cha
Authors
M. Alisa Mast, Sheila F. Murphy, David W. Clow, Colin A. Penn, Graham A. Sexstone
U.S. Geological Survey National Water Census: Colorado River Basin Geographic Focus Area Study
Introduction
The U.S. Geological Survey’s (USGS) concept of a national census (or accounting) of water resources has evolved over the last several decades as the Nation has experienced increasing concern over water availability for multiple competing uses. The implementation of a USGS National Water Census was described in the USGS 2007 science strategy document that identified the highest priorit
Authors
Breton W. Bruce, David W. Clow, Molly A. Maupin, Matthew P. Miller, Gabriel B. Senay, Graham A. Sexstone, David D. Susong
Organic carbon burial in lakes and reservoirs of the conterminous United States
Organic carbon (OC) burial in lacustrine sediments represents an important sink in the global carbon cycle; however, large-scale OC burial rates are poorly constrained, primarily because of the sparseness of available data sets. Here we present an analysis of OC burial rates in water bodies of the conterminous U.S. (CONUS) that takes advantage of recently developed national-scale data sets on rese
Authors
David W. Clow, Sarah M. Stackpoole, Kristine L. Verdin, David E. Butman, Zhi-Liang Zhu, David P. Krabbenhoft, Robert G. Striegl
Source limitation of carbon gas emissions in high-elevation mountain streams and lakes
Inland waters are an important component of the global carbon cycle through transport, storage, and direct emissions of CO2 and CH4 to the atmosphere. Despite predictions of high physical gas exchange rates due to turbulent flows and ubiquitous supersaturation of CO2—and perhaps also CH4—patterns of gas emissions are essentially undocumented for high mountain ecosystems. Much like other headwater
Authors
John T. Crawford, Mark M. Dornblaser, Emily H. Stanley, David W. Clow, Robert G. Striegl
The river as a chemostat: fresh perspectives on dissolved organic matter flowing down the river continuum
A better understanding is needed of how hydrological and biogeochemical processes control dissolved organic carbon (DOC) concentrations and dissolved organic matter (DOM) composition from headwaters downstream to large rivers. We examined a large DOM dataset from the National Water Information System of the US Geological Survey, which represents approximately 100 000 measurements of DOC concentrat
Authors
Irena F. Creed, Diane M. McKnight, Brian Pellerin, Mark B. Green, Brian A. Bergamaschi, George R. Aiken, Douglas A. Burns, Stuart E G Findlay, James B. Shanley, Robert G. Striegl, Brent T. Aulenbach, David W. Clow, Hjalmar Laudon, Brian L. McGlynn, Kevin J. McGuire, Richard A. Smith, Sarah M. Stackpoole
Science and Products
Filter Total Items: 67
Effects of backpacker use, pack stock trail use, and pack stock grazing on water-quality indicators, including nutrients, E. coli, hormones, and pharmaceuticals, in Yosemite National Park, USA
We investigated how visitor-use affects water quality in wilderness in Yosemite National Park. During the summers of 2012–2014, we collected and analyzed surface-water samples for water-quality indicators, including fecal indicator bacteria Escherichia coli, nutrients (nitrogen, phosphorus, carbon), suspended sediment concentration, pharmaceuticals, and hormones. Samples were collected upstream an
Authors
Harrison Forrester, David W. Clow, James W. Roche, Alan Heyvaert, William A. Battaglin
Inland waters and their role in the carbon cycle of Alaska
The magnitude of Alaska (AK) inland waters carbon (C) fluxes is likely to change in the future due to amplified climate warming impacts on the hydrology and biogeochemical processes in high latitude regions. Although current estimates of major aquatic C fluxes represent an essential baseline against which future change can be compared, a comprehensive assessment for AK has not yet been completed.
Authors
Sarah M. Stackpoole, David E. Butman, David W. Clow, Kristine L. Verdin, Benjamin V. Gaglioti, Hélène Genet, Robert G. Striegl
Spatial and temporal patterns of dissolved organic matter quantity and quality in the Mississippi River Basin, 1997–2013
Recent studies have found insignificant or decreasing trends in time-series dissolved organic carbon (DOC) datasets, questioning the assumption that long-term DOC concentrations in surface waters are increasing in response to anthropogenic forcing, including climate change, land use, and atmospheric acid deposition. We used the weighted regressions on time, discharge, and season (WRTDS) model to e
Authors
Sarah M. Stackpoole, Edward G. Stets, David W. Clow, Douglas A. Burns, George R. Aiken, Brent T. Aulenbach, Irena F. Creed, Robert M. Hirsch, Hjalmar Laudon, Brian Pellerin, Robert G. Striegl
Increasing aeolian dust deposition to snowpacks in the Rocky Mountains inferred from snowpack, wet deposition, and aerosol chemistry
Mountain snowpacks are a vital natural resource for ∼1.5 billion people in the northern Hemisphere, helping to meet human and ecological demand for water in excess of that provided by summer rain. Springtime warming and aeolian dust deposition accelerate snowmelt, increasing the risk of water shortages during late summer, when demand is greatest. While climate networks provide data that can be use
Authors
David W. Clow, Mark W. Williams, Paul F. Schuster
Comparison of methods for quantifying surface sublimation over seasonally snow-covered terrain
Snow sublimation can be an important component of the snow-cover mass balance, and there is considerable interest in quantifying the role of this process within the water and energy balance of snow-covered regions. In recent years, robust eddy covariance (EC) instrumentation has been used to quantify snow sublimation over snow-covered surfaces in complex mountainous terrain. However, EC can be cha
Authors
Graham A. Sexstone, David W. Clow, David I. Stannard, Steven R. Fassnacht
Numerical experiments to explain multiscale hydrological responses to mountain pine beetle tree mortality in a headwater watershed
The effects of mountain pine beetle (MPB)-induced tree mortality on a headwater hydrologic system were investigated using an integrated physical modeling framework with a high-resolution computational grid. Simulations of MPB-affected and unaffected conditions, each with identical atmospheric forcing for a normal water year, were compared at multiple scales to evaluate the effects of scale on MPB-
Authors
Colin A. Penn, Lindsay A. Bearup, Reed M. Maxwell, David W. Clow
Aquatic carbon cycling in the conterminous United States and implications for terrestrial carbon accounting
Inland water ecosystems dynamically process, transport, and sequester carbon. However, the transport of carbon through aquatic environments has not been quantitatively integrated in the context of terrestrial ecosystems. Here, we present the first integrated assessment, to our knowledge, of freshwater carbon fluxes for the conterminous United States, where 106 (range: 71–149) teragrams of carbon p
Authors
David Butman, Sarah M. Stackpoole, Edward G. Stets, Cory P. McDonald, David W. Clow, Robert G. Striegl
Water-quality response to a high-elevation wildfire in the Colorado Front Range
Water quality of the Big Thompson River in the Front Range of Colorado was studied for 2 years following a high‐elevation wildfire that started in October 2012 and burned 15% of the watershed. A combination of fixed‐interval sampling and continuous water‐quality monitors was used to examine the timing and magnitude of water‐quality changes caused by the wildfire. Prefire water quality was well cha
Authors
M. Alisa Mast, Sheila F. Murphy, David W. Clow, Colin A. Penn, Graham A. Sexstone
U.S. Geological Survey National Water Census: Colorado River Basin Geographic Focus Area Study
Introduction
The U.S. Geological Survey’s (USGS) concept of a national census (or accounting) of water resources has evolved over the last several decades as the Nation has experienced increasing concern over water availability for multiple competing uses. The implementation of a USGS National Water Census was described in the USGS 2007 science strategy document that identified the highest priorit
Authors
Breton W. Bruce, David W. Clow, Molly A. Maupin, Matthew P. Miller, Gabriel B. Senay, Graham A. Sexstone, David D. Susong
Organic carbon burial in lakes and reservoirs of the conterminous United States
Organic carbon (OC) burial in lacustrine sediments represents an important sink in the global carbon cycle; however, large-scale OC burial rates are poorly constrained, primarily because of the sparseness of available data sets. Here we present an analysis of OC burial rates in water bodies of the conterminous U.S. (CONUS) that takes advantage of recently developed national-scale data sets on rese
Authors
David W. Clow, Sarah M. Stackpoole, Kristine L. Verdin, David E. Butman, Zhi-Liang Zhu, David P. Krabbenhoft, Robert G. Striegl
Source limitation of carbon gas emissions in high-elevation mountain streams and lakes
Inland waters are an important component of the global carbon cycle through transport, storage, and direct emissions of CO2 and CH4 to the atmosphere. Despite predictions of high physical gas exchange rates due to turbulent flows and ubiquitous supersaturation of CO2—and perhaps also CH4—patterns of gas emissions are essentially undocumented for high mountain ecosystems. Much like other headwater
Authors
John T. Crawford, Mark M. Dornblaser, Emily H. Stanley, David W. Clow, Robert G. Striegl
The river as a chemostat: fresh perspectives on dissolved organic matter flowing down the river continuum
A better understanding is needed of how hydrological and biogeochemical processes control dissolved organic carbon (DOC) concentrations and dissolved organic matter (DOM) composition from headwaters downstream to large rivers. We examined a large DOM dataset from the National Water Information System of the US Geological Survey, which represents approximately 100 000 measurements of DOC concentrat
Authors
Irena F. Creed, Diane M. McKnight, Brian Pellerin, Mark B. Green, Brian A. Bergamaschi, George R. Aiken, Douglas A. Burns, Stuart E G Findlay, James B. Shanley, Robert G. Striegl, Brent T. Aulenbach, David W. Clow, Hjalmar Laudon, Brian L. McGlynn, Kevin J. McGuire, Richard A. Smith, Sarah M. Stackpoole