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Matthew Miller

Matt Miller is a Research Hydrologist with the Earth Systems Modeling Branch of the Integrated Modeling and Prediction Division in Boulder, Colorado.

His current research focuses on developing new approaches for interpreting large data sets to quantify the relationships between water quality, hydrology, land use, and climate at watershed, regional, and national scales.  Matt develops and applies modeling tools that improve process understanding of integrated terrestrial-aquatic systems to improve understanding of water availability.  Current projects include projecting the baseflow component of streamflow in the Upper Colorado River Basin, estimating future nutrient loading to estuaries in the southeastern United States, identifying sources of nitrogen to streams in Brazilian watersheds, and using water quality data to better understand groundwater discharge to streams in the Delaware River Basin.

 

Education and Certifications

  • Ph.D., Civil and Environmental Engineering, University of Colorado, Boulder (2008)

  • M.S., Civil and Environmental Engineering, University of Colorado, Boulder (2004)

  • B.S., Zoology, University of Wisconsin, Madison (2000)

Science and Products

link
Salt Wash in the San Rafael Swell with white surface salts

Salinity

Studies of Sources and Transport of Dissolved Solids (Salt) in the Colorado River Basin using the Spatially Referenced Regressions on Watershed Attributes (SPARROW) Model The Upper Colorado River Basin (UCRB) encompasses about 112,000 mi2 and discharges more than 6 million tons of dissolved solids (salt) annually to the lower Colorado River Basin. It has been estimated that between 32 and 45...
By
Utah Water Science Center
link

Salinity

Studies of Sources and Transport of Dissolved Solids (Salt) in the Colorado River Basin using the Spatially Referenced Regressions on Watershed Attributes (SPARROW) Model The Upper Colorado River Basin (UCRB) encompasses about 112,000 mi2 and discharges more than 6 million tons of dissolved solids (salt) annually to the lower Colorado River Basin. It has been estimated that between 32 and 45...
Learn More
link
Colored map showing Colorado River Basin watersheds

Baseflow

The Colorado River has been identified as the most overallocated river in the world. Considering predicted future imbalances between water supply and demand and the growing recognition that base flow (a proxy for groundwater discharge to streams) is critical for sustaining flow in streams and rivers, there is a need to develop methods to better quantify present-day base flow across large regions...
By
Utah Water Science Center
link

Baseflow

The Colorado River has been identified as the most overallocated river in the world. Considering predicted future imbalances between water supply and demand and the growing recognition that base flow (a proxy for groundwater discharge to streams) is critical for sustaining flow in streams and rivers, there is a need to develop methods to better quantify present-day base flow across large regions...
Learn More
link
Locations of USGS streamgages in the Potomac River, Smith Creek, and Difficult Run Basins in the Chesapeake Bay watershed.

High-frequency nitrate-concentration data

High-frequency nitrate-concentration data can be used to inform the development of best management practices to reduce nitrogen loading to Chesapeake Bay. Although nitrogen loads entering Chesapeake Bay have decreased in recent decades, they exceed levels that are compatible with a healthy ecosystem as a result of urbanization, agriculture, and other human activities in the bay watershed, and...
By
Chesapeake Bay Activities
link

High-frequency nitrate-concentration data

High-frequency nitrate-concentration data can be used to inform the development of best management practices to reduce nitrogen loading to Chesapeake Bay. Although nitrogen loads entering Chesapeake Bay have decreased in recent decades, they exceed levels that are compatible with a healthy ecosystem as a result of urbanization, agriculture, and other human activities in the bay watershed, and...
Learn More
link
Image: Susquehanna River - Conowingo Dam

Targeted management of a small number of catchments may help reduce nitrogen loading to Chesapeake Bay

Largest projected reductions associated with decreasing agricultural fertilizer application
By
Core Science Systems, Chesapeake Bay Activities
link

Targeted management of a small number of catchments may help reduce nitrogen loading to Chesapeake Bay

Largest projected reductions associated with decreasing agricultural fertilizer application
Learn More
link
Mountains and pine trees covered with a thick layer of snow.

Integrated Water Availability Assessments: Upper Colorado River Basin

Integrated Water Availability Assessments examine water supply, use, and availability. Snow from the Upper Colorado River Basin contributes 92% of the natural streamflow to the entire Colorado River Basin. The UCOL IWAAs will improve our understanding of the water budget, status and trends in water quality and ecological conditions, and ecosystem response to changes in climate and human water use.
By
Water Resources
link

Integrated Water Availability Assessments: Upper Colorado River Basin

Integrated Water Availability Assessments examine water supply, use, and availability. Snow from the Upper Colorado River Basin contributes 92% of the natural streamflow to the entire Colorado River Basin. The UCOL IWAAs will improve our understanding of the water budget, status and trends in water quality and ecological conditions, and ecosystem response to changes in climate and human water use.
Learn More

Daily-timestep and monthly-timestep estimates of baseflow at 49 reference stream gages located within 25 miles of the Delaware River basin watershed boundary for the years 1950 through 2015

This USGS data release contains daily-timestep and monthly-timestep estimates of baseflow at 49 reference stream gages located within 25 miles of the Delaware River basin watershed boundary. Estimates are provided for the available period of record of streamflow data at each site between 1950 and 2015. A two-parameter recursive digital filter was used to estimate baseflow at the selected stream ga
By
New Jersey Water Science Center

Natural Monthly Flow Estimates for the Conterminous United States, 1950-2015

This metadata record describes monthly estimates of natural stream flows for greater than 2.5 million stream reaches, defined by the National Hydrography Dataset (NHD) Version 2.0, in the conterminous United States for the period 1950-2015. A statistical machine learning technique - random forest modeling - was applied to estimate natural flows using 200 potential predictor variables. The dataset
By
National Water Quality Program
Filter Total Items: 40

Predicting redox-sensitive contaminant concentrations in groundwater using random forest classification

Machine learning techniques were applied to a large (n > 10,000) compliance monitoring database to predict the occurrence of several redox-active constituents in groundwater across a large watershed. Specifically, random forest classification was used to determine the probabilities of detecting elevated concentrations of nitrate, iron, and arsenic in the Fox, Wolf, Peshtigo, and surrounding waters
By
Water Resources, Oregon Water Science Center

Variability of dissolved organic carbon in precipitation during storms at the Shale Hills Critical Zone Observatory

Organic compounds are removed from the atmosphere and deposited to the earth's surface via precipitation. In this study, we quantified variations of dissolved organic carbon (DOC) in precipitation during storm events at the Shale Hills Critical Zone Observatory, a forested watershed in central Pennsylvania (USA). Precipitation samples were collected consecutively throughout the storm during 13 eve
By
Water Resources, Utah Water Science Center

Enhanced and updated spatially referenced statistical assessment of dissolved-solids load sources and transport in streams of the Upper Colorado River Basin

Approximately 6.4 million tons of dissolved solids are discharged from the Upper Colorado River Basin (UCRB) to the Lower Colorado River Basin each year. This results in substantial economic damages, and tens of millions of dollars are spent annually on salinity control projects designed to reduce salinity loads in surface waters of the UCRB. Dissolved solids in surface water and groundwater have
By
Water Resources, Utah Water Science Center

Patterns of diel variation in nitrate concentrations in the Potomac River

The Potomac River is a large source of N to Chesapeake Bay, where reducing nutrient loads is a focus of efforts to improve trophic status. Better understanding of NO3– loss, reflected in part by diel variation in NO3– concentrations, may refine model predictions of N loads to the Bay. We analyzed 2 y of high-frequency NO3– sensor data in the Potomac to quantify seasonal variation in the magnitude
By
Water Resources, Chesapeake Bay Activities, New York Water Science Center, California Water Science Center

Atmospheric inputs of organic matter to a forested watershed: Variations from storm to storm over the seasons

The objectives of this study were to determine the quantity and chemical composition of precipitation inputs of dissolved organic carbon (DOC) to a forested watershed; and to characterize the associated temporal variability. We sampled most precipitation that occurred from May 2012 through August 2013 at the Susquehanna Shale Hills Critical Zone Observatory (Pennsylvania, USA). Sub-event precipita
By
Water Resources, Utah Water Science Center

Variation of organic matter quantity and quality in streams at Critical Zone Observatory watersheds

The quantity and chemical composition of dissolved organic matter (DOM) in surface waters influence ecosystem processes and anthropogenic use of freshwater. However, despite the importance of understanding spatial and temporal patterns in DOM, measures of DOM quality are not routinely included as part of large-scale ecosystem monitoring programs and variations in analytical procedures can introduc
By
Water Resources, Utah Water Science Center

Quantifying watershed-scale groundwater loading and in-stream fate of nitrate using high-frequency water quality data

We describe a new approach that couples hydrograph separation with high-frequency nitrate data to quantify time-variable groundwater and runoff loading of nitrate to streams, and the net in-stream fate of nitrate at the watershed-scale. The approach was applied at three sites spanning gradients in watershed size and land use in the Chesapeake Bay watershed. Results indicate that 58-73% of the annu
By
Water Resources, National Water Quality Program, California Water Science Center, Chesapeake Bay Activities, New York Water Science Center, Oregon Water Science Center, Utah Water Science Center, Virginia and West Virginia Water Science Center, Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center

The importance of base flow in sustaining surface water flow in the Upper Colorado River Basin

The Colorado River has been identified as the most overallocated river in the world. Considering predicted future imbalances between water supply and demand and the growing recognition that base flow (a proxy for groundwater discharge to streams) is critical for sustaining flow in streams and rivers, there is a need to develop methods to better quantify present-day base flow across large regions.
By
Water Resources, National Water Quality Program, Utah Water Science Center

Climate regulates alpine lake ice cover phenology and aquatic ecosystem structure

High-elevation aquatic ecosystems are highly vulnerable to climate change, yet relatively few records are available to characterize shifts in ecosystem structure or their underlying mechanisms. Using a long-term dataset on seven alpine lakes (3126 to 3620 m) in Colorado, USA, we show that ice-off dates have shifted seven days earlier over the past 33 years and that spring weather conditions – espe
By
Water Resources, Utah Water Science Center

A new approach for continuous estimation of baseflow using discrete water quality data: Method description and comparison with baseflow estimates from two existing approaches

Understanding how watershed characteristics and climate influence the baseflow component of stream discharge is a topic of interest to both the scientific and water management communities. Therefore, the development of baseflow estimation methods is a topic of active research. Previous studies have demonstrated that graphical hydrograph separation (GHS) and conductivity mass balance (CMB) methods
By
Water Resources, Utah Water Science Center, Kansas Water Science Center

Limnology of the Green Lakes Valley: Phytoplankton ecology and dissolved organic matter biogeochemistry at a long-term ecological research site

Background: Surface waters are the lowest points in the landscape, and therefore serve as excellent integrators and indicators of changes taking place in the surrounding terrestrial and atmospheric environment.Aims: Here we synthesise the findings of limnological studies conducted during the past 15 years in streams and lakes in the Green Lakes Valley, which is part of the Niwot Ridge Long-term Ec
By
Water Resources, Utah Water Science Center

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

Pre-USGS Publications

Miller, M.P., D.M. McKnight, R. M. Cory, M. Williams, R. L. Runkel (2006) Hyporheic exchange and fulvic acid redox reactions in an alpine stream/wetland ecosystem, Colorado Front Range. Environmental Science and Technology, 40, 5943-5949
Gardner, E.M, D.M. McKnight, W.M. Lewis, M.P. Miller (2008) Effects of nutrient enrichment on phytoplankton in an alpine lake, Colorado, U.S.A. Arctic, Antarctic, and Alpine Research, 40(1), 55-64.
Tipping, E., H.T. Corbishley, J.F. Koprivnjak, D.J. Lapworth, M.P. Miller, C.D. Vincent, J. Hamilton Taylor (2009) Quantification of natural DOM from UV absorption at two wavelengths. Environmental Chemistry, 6, 472-476.
Miller, M.P., D.M. McKnight, J. Cullis, A. Greene, K. Vietti, D. Liptzin (2009) Factors controlling streambed coverage of Didymosphenia geminata in two regulated streams in the Colorado Front Range. Hydrobiologia, 630, 207-218.
Miller, M.P., D.M. McKnight, S.C. Chapra, M.W. Williams (2009) A model of degradation and production of three pools of dissolved organic matter in an alpine lake. Limnology and Oceanography, 54(6), 2213-2227.
Miller, M.P., D.M. McKnight, S.C. Chapra (2009) Production of microbially derived fulvic acid from photolysis of quinone-containing extracellular products of phytoplankton. Aquatic Sciences, 71, 170-178.
Flanagan, C.M., D.M. McKnight, D. Liptzin, M.W. Williams, M.P. Miller (2009) Response of the phytoplankton community in an alpine lake to drought conditions: Colorado Rocky Mountain Front Range, U.S.A. Arctic, Antarctic, and Alpine Research, 41(2), 191-203.
Fellman, J.B., M.P. Miller, R.M. Cory, D.V. D’Amore, D. White (2009) Characterizing dissolved organic matter using PARAFAC modeling of fluorescence spectroscopy: A comparison of two models. Environmental Science and Technology, 43, 6228-6234.
Mladenov, N., Y. Zheng, M.P. Miller, D.R. Nemergut, T. Legg, B. Simone, C. Hageman, M. M. Rahman, K. M. Ahmed, D.M. McKnight (2010) Dissolved organic matter sources and consequences for iron and arsenic mobilization in Bangladesh aquifers. Environmental Science and Technology, 44, 123-128.
Miller, M.P., B.E. Simone, D.M. McKnight, R.M. Cory, M.W. Williams, E.W. Boyer (2010) New light on a dark subject: Comment. Aquatic Sciences, 72: 269-275.
Miller, M.P., D.M. McKnight (2010) Comparison of seasonal changes in fluorescent dissolved organic matter among aquatic lake and stream sites in the Green Lakes Valley. Journal of Geophysical Research-Biogeosciences, 115, GOOF12, doi:10.1029/2009JG000985.
Cory, R.M., M.P. Miller, D.M. McKnight, J. Guerard, P. Miller (2010) Effect of instrument-specific response on the analysis of fulvic acid fluorescence spectra. Limnology and Oceanography Methods, 8, 67-78.
Brasher, A.M.D., C.M. Albano, R.N. Close, Q.H. Cannon, and M.P. Miller (2010) Macroinvertebrate communities and habitat characteristics in the northern and southern Colorado Plateau networks: Natural Resources Technical Report, NPS/NCPN/NRTR-2010/320, 107pp.
Brasher, A.M.D., T. Jones, A. Farahi, M.P. Miller, K. Kozar (2011) Pacific Islands Stream Monitoring Protocol: Fish, Shrimp, Snails, and Habitat Characterization. Natural Resources Technical Report, NPS/PACN/NRR-2011/468, 357pp.
Gabor, R., A. Baker, D.M. McKnight, M.P. Miller (2014) Fluorescence indices and their interpretation. In Coble, P.G, Lead, J., Baker, A., Reynolds, D.M, and Spencer, R.G.M., eds., Aquatic Organic Matter Fluorescence Cambridge University Press.
Georgek, J.L., D.K. Solomon, V.M. Heilweil, M.P. Miller (2018) Using tracer-derived groundwater transit times to assess storage within a high-elevation watershed of the Upper Colorado River Basin. Hydrogeol. J., 26, 467-480, doi:10.1007/s10040-017-1655-4.
Bowman, W.D., D.R. Nemergut, D.M. McKnight, M.P. Miller, M.W. Williams (2014) A slide down a slippery slope-alpine ecosystem responses to nitrogen deposition. Plant Ecology and Diversity, 8, 727-738, doi:10.1080/17550874.2014.984786
link

Targeted management of a small number of catchments may help reduce nitrogen loading to Chesapeake Bay

A new USGS study uses the SPARROW (SPAtially Referenced Regression On Watershed attributes) model to assess how nitrogen loading to the Chesapeake Bay...

Read Article

Science and Products

  • Science
    link
    Salt Wash in the San Rafael Swell with white surface salts

    Salinity

    Studies of Sources and Transport of Dissolved Solids (Salt) in the Colorado River Basin using the Spatially Referenced Regressions on Watershed Attributes (SPARROW) Model The Upper Colorado River Basin (UCRB) encompasses about 112,000 mi2 and discharges more than 6 million tons of dissolved solids (salt) annually to the lower Colorado River Basin. It has been estimated that between 32 and 45...
    By
    Utah Water Science Center
    link

    Salinity

    Studies of Sources and Transport of Dissolved Solids (Salt) in the Colorado River Basin using the Spatially Referenced Regressions on Watershed Attributes (SPARROW) Model The Upper Colorado River Basin (UCRB) encompasses about 112,000 mi2 and discharges more than 6 million tons of dissolved solids (salt) annually to the lower Colorado River Basin. It has been estimated that between 32 and 45...
    Learn More
    link
    Colored map showing Colorado River Basin watersheds

    Baseflow

    The Colorado River has been identified as the most overallocated river in the world. Considering predicted future imbalances between water supply and demand and the growing recognition that base flow (a proxy for groundwater discharge to streams) is critical for sustaining flow in streams and rivers, there is a need to develop methods to better quantify present-day base flow across large regions...
    By
    Utah Water Science Center
    link

    Baseflow

    The Colorado River has been identified as the most overallocated river in the world. Considering predicted future imbalances between water supply and demand and the growing recognition that base flow (a proxy for groundwater discharge to streams) is critical for sustaining flow in streams and rivers, there is a need to develop methods to better quantify present-day base flow across large regions...
    Learn More
    link
    Locations of USGS streamgages in the Potomac River, Smith Creek, and Difficult Run Basins in the Chesapeake Bay watershed.

    High-frequency nitrate-concentration data

    High-frequency nitrate-concentration data can be used to inform the development of best management practices to reduce nitrogen loading to Chesapeake Bay. Although nitrogen loads entering Chesapeake Bay have decreased in recent decades, they exceed levels that are compatible with a healthy ecosystem as a result of urbanization, agriculture, and other human activities in the bay watershed, and...
    By
    Chesapeake Bay Activities
    link

    High-frequency nitrate-concentration data

    High-frequency nitrate-concentration data can be used to inform the development of best management practices to reduce nitrogen loading to Chesapeake Bay. Although nitrogen loads entering Chesapeake Bay have decreased in recent decades, they exceed levels that are compatible with a healthy ecosystem as a result of urbanization, agriculture, and other human activities in the bay watershed, and...
    Learn More
    link
    Image: Susquehanna River - Conowingo Dam

    Targeted management of a small number of catchments may help reduce nitrogen loading to Chesapeake Bay

    Largest projected reductions associated with decreasing agricultural fertilizer application
    By
    Core Science Systems, Chesapeake Bay Activities
    link

    Targeted management of a small number of catchments may help reduce nitrogen loading to Chesapeake Bay

    Largest projected reductions associated with decreasing agricultural fertilizer application
    Learn More
    link
    Mountains and pine trees covered with a thick layer of snow.

    Integrated Water Availability Assessments: Upper Colorado River Basin

    Integrated Water Availability Assessments examine water supply, use, and availability. Snow from the Upper Colorado River Basin contributes 92% of the natural streamflow to the entire Colorado River Basin. The UCOL IWAAs will improve our understanding of the water budget, status and trends in water quality and ecological conditions, and ecosystem response to changes in climate and human water use.
    By
    Water Resources
    link

    Integrated Water Availability Assessments: Upper Colorado River Basin

    Integrated Water Availability Assessments examine water supply, use, and availability. Snow from the Upper Colorado River Basin contributes 92% of the natural streamflow to the entire Colorado River Basin. The UCOL IWAAs will improve our understanding of the water budget, status and trends in water quality and ecological conditions, and ecosystem response to changes in climate and human water use.
    Learn More
  • Data

    Daily-timestep and monthly-timestep estimates of baseflow at 49 reference stream gages located within 25 miles of the Delaware River basin watershed boundary for the years 1950 through 2015

    This USGS data release contains daily-timestep and monthly-timestep estimates of baseflow at 49 reference stream gages located within 25 miles of the Delaware River basin watershed boundary. Estimates are provided for the available period of record of streamflow data at each site between 1950 and 2015. A two-parameter recursive digital filter was used to estimate baseflow at the selected stream ga
    By
    New Jersey Water Science Center

    Natural Monthly Flow Estimates for the Conterminous United States, 1950-2015

    This metadata record describes monthly estimates of natural stream flows for greater than 2.5 million stream reaches, defined by the National Hydrography Dataset (NHD) Version 2.0, in the conterminous United States for the period 1950-2015. A statistical machine learning technique - random forest modeling - was applied to estimate natural flows using 200 potential predictor variables. The dataset
    By
    National Water Quality Program
  • Publications
    Filter Total Items: 40

    Predicting redox-sensitive contaminant concentrations in groundwater using random forest classification

    Machine learning techniques were applied to a large (n > 10,000) compliance monitoring database to predict the occurrence of several redox-active constituents in groundwater across a large watershed. Specifically, random forest classification was used to determine the probabilities of detecting elevated concentrations of nitrate, iron, and arsenic in the Fox, Wolf, Peshtigo, and surrounding waters
    By
    Water Resources, Oregon Water Science Center

    Variability of dissolved organic carbon in precipitation during storms at the Shale Hills Critical Zone Observatory

    Organic compounds are removed from the atmosphere and deposited to the earth's surface via precipitation. In this study, we quantified variations of dissolved organic carbon (DOC) in precipitation during storm events at the Shale Hills Critical Zone Observatory, a forested watershed in central Pennsylvania (USA). Precipitation samples were collected consecutively throughout the storm during 13 eve
    By
    Water Resources, Utah Water Science Center

    Enhanced and updated spatially referenced statistical assessment of dissolved-solids load sources and transport in streams of the Upper Colorado River Basin

    Approximately 6.4 million tons of dissolved solids are discharged from the Upper Colorado River Basin (UCRB) to the Lower Colorado River Basin each year. This results in substantial economic damages, and tens of millions of dollars are spent annually on salinity control projects designed to reduce salinity loads in surface waters of the UCRB. Dissolved solids in surface water and groundwater have
    By
    Water Resources, Utah Water Science Center

    Patterns of diel variation in nitrate concentrations in the Potomac River

    The Potomac River is a large source of N to Chesapeake Bay, where reducing nutrient loads is a focus of efforts to improve trophic status. Better understanding of NO3– loss, reflected in part by diel variation in NO3– concentrations, may refine model predictions of N loads to the Bay. We analyzed 2 y of high-frequency NO3– sensor data in the Potomac to quantify seasonal variation in the magnitude
    By
    Water Resources, Chesapeake Bay Activities, New York Water Science Center, California Water Science Center

    Atmospheric inputs of organic matter to a forested watershed: Variations from storm to storm over the seasons

    The objectives of this study were to determine the quantity and chemical composition of precipitation inputs of dissolved organic carbon (DOC) to a forested watershed; and to characterize the associated temporal variability. We sampled most precipitation that occurred from May 2012 through August 2013 at the Susquehanna Shale Hills Critical Zone Observatory (Pennsylvania, USA). Sub-event precipita
    By
    Water Resources, Utah Water Science Center

    Variation of organic matter quantity and quality in streams at Critical Zone Observatory watersheds

    The quantity and chemical composition of dissolved organic matter (DOM) in surface waters influence ecosystem processes and anthropogenic use of freshwater. However, despite the importance of understanding spatial and temporal patterns in DOM, measures of DOM quality are not routinely included as part of large-scale ecosystem monitoring programs and variations in analytical procedures can introduc
    By
    Water Resources, Utah Water Science Center

    Quantifying watershed-scale groundwater loading and in-stream fate of nitrate using high-frequency water quality data

    We describe a new approach that couples hydrograph separation with high-frequency nitrate data to quantify time-variable groundwater and runoff loading of nitrate to streams, and the net in-stream fate of nitrate at the watershed-scale. The approach was applied at three sites spanning gradients in watershed size and land use in the Chesapeake Bay watershed. Results indicate that 58-73% of the annu
    By
    Water Resources, National Water Quality Program, California Water Science Center, Chesapeake Bay Activities, New York Water Science Center, Oregon Water Science Center, Utah Water Science Center, Virginia and West Virginia Water Science Center, Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center

    The importance of base flow in sustaining surface water flow in the Upper Colorado River Basin

    The Colorado River has been identified as the most overallocated river in the world. Considering predicted future imbalances between water supply and demand and the growing recognition that base flow (a proxy for groundwater discharge to streams) is critical for sustaining flow in streams and rivers, there is a need to develop methods to better quantify present-day base flow across large regions.
    By
    Water Resources, National Water Quality Program, Utah Water Science Center

    Climate regulates alpine lake ice cover phenology and aquatic ecosystem structure

    High-elevation aquatic ecosystems are highly vulnerable to climate change, yet relatively few records are available to characterize shifts in ecosystem structure or their underlying mechanisms. Using a long-term dataset on seven alpine lakes (3126 to 3620 m) in Colorado, USA, we show that ice-off dates have shifted seven days earlier over the past 33 years and that spring weather conditions – espe
    By
    Water Resources, Utah Water Science Center

    A new approach for continuous estimation of baseflow using discrete water quality data: Method description and comparison with baseflow estimates from two existing approaches

    Understanding how watershed characteristics and climate influence the baseflow component of stream discharge is a topic of interest to both the scientific and water management communities. Therefore, the development of baseflow estimation methods is a topic of active research. Previous studies have demonstrated that graphical hydrograph separation (GHS) and conductivity mass balance (CMB) methods
    By
    Water Resources, Utah Water Science Center, Kansas Water Science Center

    Limnology of the Green Lakes Valley: Phytoplankton ecology and dissolved organic matter biogeochemistry at a long-term ecological research site

    Background: Surface waters are the lowest points in the landscape, and therefore serve as excellent integrators and indicators of changes taking place in the surrounding terrestrial and atmospheric environment.Aims: Here we synthesise the findings of limnological studies conducted during the past 15 years in streams and lakes in the Green Lakes Valley, which is part of the Niwot Ridge Long-term Ec
    By
    Water Resources, Utah Water Science Center

    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

    Pre-USGS Publications

    Miller, M.P., D.M. McKnight, R. M. Cory, M. Williams, R. L. Runkel (2006) Hyporheic exchange and fulvic acid redox reactions in an alpine stream/wetland ecosystem, Colorado Front Range. Environmental Science and Technology, 40, 5943-5949
    Gardner, E.M, D.M. McKnight, W.M. Lewis, M.P. Miller (2008) Effects of nutrient enrichment on phytoplankton in an alpine lake, Colorado, U.S.A. Arctic, Antarctic, and Alpine Research, 40(1), 55-64.
    Tipping, E., H.T. Corbishley, J.F. Koprivnjak, D.J. Lapworth, M.P. Miller, C.D. Vincent, J. Hamilton Taylor (2009) Quantification of natural DOM from UV absorption at two wavelengths. Environmental Chemistry, 6, 472-476.
    Miller, M.P., D.M. McKnight, J. Cullis, A. Greene, K. Vietti, D. Liptzin (2009) Factors controlling streambed coverage of Didymosphenia geminata in two regulated streams in the Colorado Front Range. Hydrobiologia, 630, 207-218.
    Miller, M.P., D.M. McKnight, S.C. Chapra, M.W. Williams (2009) A model of degradation and production of three pools of dissolved organic matter in an alpine lake. Limnology and Oceanography, 54(6), 2213-2227.
    Miller, M.P., D.M. McKnight, S.C. Chapra (2009) Production of microbially derived fulvic acid from photolysis of quinone-containing extracellular products of phytoplankton. Aquatic Sciences, 71, 170-178.
    Flanagan, C.M., D.M. McKnight, D. Liptzin, M.W. Williams, M.P. Miller (2009) Response of the phytoplankton community in an alpine lake to drought conditions: Colorado Rocky Mountain Front Range, U.S.A. Arctic, Antarctic, and Alpine Research, 41(2), 191-203.
    Fellman, J.B., M.P. Miller, R.M. Cory, D.V. D’Amore, D. White (2009) Characterizing dissolved organic matter using PARAFAC modeling of fluorescence spectroscopy: A comparison of two models. Environmental Science and Technology, 43, 6228-6234.
    Mladenov, N., Y. Zheng, M.P. Miller, D.R. Nemergut, T. Legg, B. Simone, C. Hageman, M. M. Rahman, K. M. Ahmed, D.M. McKnight (2010) Dissolved organic matter sources and consequences for iron and arsenic mobilization in Bangladesh aquifers. Environmental Science and Technology, 44, 123-128.
    Miller, M.P., B.E. Simone, D.M. McKnight, R.M. Cory, M.W. Williams, E.W. Boyer (2010) New light on a dark subject: Comment. Aquatic Sciences, 72: 269-275.
    Miller, M.P., D.M. McKnight (2010) Comparison of seasonal changes in fluorescent dissolved organic matter among aquatic lake and stream sites in the Green Lakes Valley. Journal of Geophysical Research-Biogeosciences, 115, GOOF12, doi:10.1029/2009JG000985.
    Cory, R.M., M.P. Miller, D.M. McKnight, J. Guerard, P. Miller (2010) Effect of instrument-specific response on the analysis of fulvic acid fluorescence spectra. Limnology and Oceanography Methods, 8, 67-78.
    Brasher, A.M.D., C.M. Albano, R.N. Close, Q.H. Cannon, and M.P. Miller (2010) Macroinvertebrate communities and habitat characteristics in the northern and southern Colorado Plateau networks: Natural Resources Technical Report, NPS/NCPN/NRTR-2010/320, 107pp.
    Brasher, A.M.D., T. Jones, A. Farahi, M.P. Miller, K. Kozar (2011) Pacific Islands Stream Monitoring Protocol: Fish, Shrimp, Snails, and Habitat Characterization. Natural Resources Technical Report, NPS/PACN/NRR-2011/468, 357pp.
    Gabor, R., A. Baker, D.M. McKnight, M.P. Miller (2014) Fluorescence indices and their interpretation. In Coble, P.G, Lead, J., Baker, A., Reynolds, D.M, and Spencer, R.G.M., eds., Aquatic Organic Matter Fluorescence Cambridge University Press.
    Georgek, J.L., D.K. Solomon, V.M. Heilweil, M.P. Miller (2018) Using tracer-derived groundwater transit times to assess storage within a high-elevation watershed of the Upper Colorado River Basin. Hydrogeol. J., 26, 467-480, doi:10.1007/s10040-017-1655-4.
    Bowman, W.D., D.R. Nemergut, D.M. McKnight, M.P. Miller, M.W. Williams (2014) A slide down a slippery slope-alpine ecosystem responses to nitrogen deposition. Plant Ecology and Diversity, 8, 727-738, doi:10.1080/17550874.2014.984786
  • News
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    Targeted management of a small number of catchments may help reduce nitrogen loading to Chesapeake Bay

    A new USGS study uses the SPARROW (SPAtially Referenced Regression On Watershed attributes) model to assess how nitrogen loading to the Chesapeake Bay...

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