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William H Farmer, Ph.D.

Will Farmer is the Acting Director for the Northeast Climate Adaptation Science Center.

Science and Products

Filter Total Items: 29

Parameter estimation at the conterminous United States scale and streamflow routing enhancements for the National Hydrologic Model infrastructure application of the Precipitation-Runoff Modeling System (NHM-PRMS)

This report documents a three-part continental-scale calibration procedure and a new streamflow routing algorithm using the U.S. Geological Survey National Hydrologic Model (NHM) infrastructure along with an application of the Precipitation-Runoff Modeling System (PRMS). The traditional approach to hydrologic model calibration and evaluation, which relies on comparing observed and simulated stream
Authors
Lauren E. Hay, Jacob H. LaFontaine, Ashley E. Van Beusekom, Parker A. Norton, William H. Farmer, R. Steve Regan, Steven L. Markstrom, Jesse E. Dickinson
By
Water Resources Mission Area, South Atlantic Water Science Center (SAWSC)

Stochastic watershed model ensembles for long-range planning: Verification and validation

Deterministic watershed models (DWMs) are used in nearly all hydrologic planning, design, and management activities, yet they cannot generate streamflow ensembles needed for hydrologic risk management (HRM). The stochastic component of DWMs is often ignored in practice, leading to a systematic bias in extreme events. Since traditional stochastic streamflow models used in HRM struggle to account fo
Authors
Ghazal Shabestanipour, Zachary P Brodeur, William H. Farmer, Scott Steinschneider, Richard M Vogel, Jonathan Lamontagne
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Ecosystems Mission Area, Climate Adaptation Science Centers

Predictions and drivers of sub-reach-scale annual streamflow permanence for the upper Missouri River basin: 1989-2018

The presence of year-round surface water in streams (i.e., streamflow permanence) is an important factor for identifying aquatic habitat availability, determining the regulatory status of streams, managing land use change, allocating water resources, and designing scientific studies. However, accurate, high resolution, and dynamic prediction of streamflow permanence that accounts for year-to-year
Authors
Roy Sando, Kristin Jaeger, William H. Farmer, Theodore B. Barnhart, Ryan R. McShane, Toby L. Welborn, Kendra E. Kaiser, Konrad Hafen, Kyle W. Blasch, Benjamin C. York, Alden Shallcross
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Water Resources Mission Area, Oklahoma-Texas Water Science Center, Washington Water Science Center, Wyoming-Montana Water Science Center, Dakota Water Science Center

Evaluating hydrologic region assignment techniques for ungaged basins in Alaska, USA

Building continental-scale hydrologic models in data-sparse regions requires an understanding of spatial variation in hydrologic processes. Extending these models to ungaged locations requires techniques to group ungaged locations with gaged ones to make process importance and model parameter transfer decisions to ungaged locations. This analysis (1) tested the utility of fundamental streamflow st
Authors
Theodore B. Barnhart, William H. Farmer, John C. Hammond, Graham A. Sexstone, Janet H. Curran, Joshua C. Koch, Jessica M. Driscoll
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Water Resources Mission Area, Alaska Science Center, Wyoming-Montana Water Science Center

On the role of climate in monthly baseflow changes across the continental United States

Baseflow is the portion of streamflow that comes from groundwater and subsurface sources. Although baseflow is essential for sustaining streams during low flow and drought periods, we have little information about how and why it has changed over large regions of the continental United States. The objective of this study was to evaluate how changes in the climate system have affected observed month
Authors
Jessica R. Ayers, Gabriele Villarini, Keith Schilling, Christopher Jones, Andrea E. Brookfield, Samuel Zipper, William H. Farmer
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Water Resources Mission Area

Quantifying streamflow depletion from groundwater pumping: A practical review of past and emerging approaches for water management

Groundwater pumping can cause reductions in streamflow (“streamflow depletion”) that must be quantified for conjunctive management of groundwater and surface water resources. However, streamflow depletion cannot be measured directly and is challenging to estimate because pumping impacts are masked by streamflow variability due to other factors. Here, we conduct a management-focused review of analy
Authors
Samuel Zipper, William H. Farmer, Andrea E. Brookfield, Hoori Ajami, Howard W. Reeves, Chloe Wardropper, John C. Hammond, Tom Gleeson, Jillian M. Deines
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Water Resources Mission Area, Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center

Implications of model selection: A comparison of publicly available, conterminous US-extent hydrologic component estimates

Spatiotemporally continuous estimates of the hydrologic cycle are often generated through hydrologic modeling, reanalysis, or remote sensing (RS) methods and are commonly applied as a supplement to, or a substitute for, in situ measurements when observational data are sparse or unavailable. This study compares estimates of precipitation (P), actual evapotranspiration (ET), runoff (R), snow water e
Authors
Samuel Saxe, William H. Farmer, Jessica M. Driscoll, Terri S. Hogue
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Water Resources Mission Area

A comparison between generalized least squares regression and top-kriging for homogeneous cross-correlated flood regions

Spatial cross-correlation among flood sequences impacts the accuracy of regional predictors. Our study investigates this impact for two regionalization procedures, generalized least squares (GLS) regression and top-kriging (TK), which deal with cross-correlation in two fundamentally different ways and therefore might be associated with different accuracy and uncertainty of predicted flood quantile
Authors
Persiano Simone, Jose Luis Salinas, Jery Russell Stedinger, William H. Farmer, David Lun, Alberto Viglione, Gunter Bloschl, Attilio Castellarin
By
Water Resources Mission Area

Evaluation of uncertainty intervals for daily, statistically derived streamflow estimates at ungaged basins across the continental U.S.

Streamflow estimation methods that transfer information from an index gage to an ungaged site are commonly used; however, uncertainty in daily streamflow estimates are often not adequately quantified. In this study, daily streamflow was simulated at 1,331 validation streamgages across the continental United States using four transfer-based streamflow estimation methods. Empirical 95 percent unce
Authors
Sara B. Levin, William H. Farmer
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Upper Midwest Water Science Center

Copula theory as a generalized framework for flow-duration curve-based streamflow estimates in ungaged and partially gaged catchments

Flow‐duration curve (FDC) based streamflow estimation methods involve estimating an FDC at an ungaged or partially gaged location and using the time series of nonexceedance probabilities estimated from donor streamgage sites to generate estimates of streamflow. We develop a mathematical framework to illustrate the connection between copulas and prior FDC‐based approaches. The performance of copula
Authors
Scott C. Worland, Scott Steinschneider, William H. Farmer, William H. Asquith, Rodney White
By
Lower Mississippi-Gulf Water Science Center, Gulf of Mexico

Simulation of water availability in the Southeastern United States for historical and potential future climate and land-cover conditions

A study was conducted by the U.S. Geological Survey (USGS), in cooperation with the Gulf Coastal Plains and Ozarks Landscape Conservation Cooperative (GCPO LCC) and the Department of the Interior Southeast Climate Adaptation Science Center, to evaluate the hydrologic response of a daily time step hydrologic model to historical observations and projections of potential climate and land-cover change
Authors
Jacob H. LaFontaine, Rheannon M. Hart, Lauren E. Hay, William H. Farmer, Andy R. Bock, Roland J. Viger, Steven L. Markstrom, R. Steve Regan, Jessica M. Driscoll
By
Water Resources Mission Area, Colorado Water Science Center, Lower Mississippi-Gulf Water Science Center, New Mexico Water Science Center, South Atlantic Water Science Center (SAWSC)

GRACE storage change characteristics (2003–2016) over major surface basins and principal aquifers in the Conterminous United States

In this research, we characterized the changes in Gravity Recovery and Climate Experiment’s (GRACE) monthly total water storage anomaly (TWSA) in 18 surface basins and 12 principal aquifers in the Conterminous United States (CONUS) over 2003–2016. Regions with high variability in storage were identified. Ten basins and 4 aquifers showed significant change in storage. Eight surface basins and 8 aqu
Authors
Naga Manohar Velpuri, Gabriel Senay, Jessica M. Driscoll, Samuel Saxe, Lauren E. Hay, William H. Farmer, Julie E. Kiang
By
Earth Resources Observation and Science (EROS) Center
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Shepaug River Peter's Dam gage pool

CAP Future of Aquatic Flows Cohort (2022-24)

The 2022-2024 Climate Adaptation Postdoctoral (CAP) Fellows cohort will explore how climate change is altering aquatic flows in streams and rivers across the country and how climate can be integrated into aquatic ecosystem management.
By
Climate Adaptation Science Centers
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CAP Future of Aquatic Flows Cohort (2022-24)

The 2022-2024 Climate Adaptation Postdoctoral (CAP) Fellows cohort will explore how climate change is altering aquatic flows in streams and rivers across the country and how climate can be integrated into aquatic ecosystem management.
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Streamflow depletion. Image shows stream on left and right, with a blank space in the middle and a question mark.

Visualizing the Invisible: Causes, Consequences, Changes, and Management of Streamflow Depletion Across the U.S.

Streamflow is declining in many parts of the United States (US) due to factors including groundwater pumping, land use change, and climate change. Streamflow depletion, a reduction in groundwater discharge to a stream due to human activities such as pumping and/or land use change, tends to evolve slowly and can be entirely invisible for many years to decades. This is because streamflow depletion c
By
John Wesley Powell Center for Analysis and Synthesis
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Visualizing the Invisible: Causes, Consequences, Changes, and Management of Streamflow Depletion Across the U.S.

Streamflow is declining in many parts of the United States (US) due to factors including groundwater pumping, land use change, and climate change. Streamflow depletion, a reduction in groundwater discharge to a stream due to human activities such as pumping and/or land use change, tends to evolve slowly and can be entirely invisible for many years to decades. This is because streamflow depletion c
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Trend Reproduction

As part of the National Water Budget Project, our objective is to quantify how well observed trends are simulated.
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New England Water Science Center
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Trend Reproduction

As part of the National Water Budget Project, our objective is to quantify how well observed trends are simulated.
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USGS science for a changing world logo

Water availability for ungauged rivers: an integrative, multi-model approach to estimate water availability at ungauged rivers across the United States

There has been increasing attention placed on the need for water availability information at ungauged locations, particularly related to balancing human and ecological needs for water. Critical to assessing water availability is the necessity for daily streamflow time series; however, most of the rivers in the United States are ungauged. This proposal leverages over $1M currently allocated to the
By
John Wesley Powell Center for Analysis and Synthesis
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Water availability for ungauged rivers: an integrative, multi-model approach to estimate water availability at ungauged rivers across the United States

There has been increasing attention placed on the need for water availability information at ungauged locations, particularly related to balancing human and ecological needs for water. Critical to assessing water availability is the necessity for daily streamflow time series; however, most of the rivers in the United States are ungauged. This proposal leverages over $1M currently allocated to the
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Filter Total Items: 14

Basin Characteristics and Streamflow Statistics for Selected Gages, Alaska, USA (ver. 2.0, September, 2022)

This data release documents the data used for the associated publication "Evaluating hydrologic region assignment techniques for ungaged watersheds in Alaska, USA" (Barnhart and others, 2022) The data sets within this release are stored in 14 files: (1) Streamflow observations and sites used. (2) Statistically estimated streamflow values computed for each site. (3) Streamflow statistics computed f
By
Wyoming-Montana Water Science Center

Statistical daily streamflow estimates at GAGES-II non-reference streamgages in the conterminous United States, Water Years 1981-2017

This data release contains daily time series estimates of natural streamflow at 5,439 GAGES-II non-reference streamgages in 19 study regions across the conterminous United States from October 1, 1980 through September 30, 2017, using five statistical techniques: nearest-neighbor drainage area ratio (NNDAR), map-correlation drainage area ratio (MCDAR), nearest-neighbor nonlinear spatial interpolati
By
Central Midwest Water Science Center

Cross-validation results for five statistical methods of daily streamflow estimation at 1,385 reference streamgages in the conterminous United States, Water Years 1981-2017

This data release contains daily time series estimates of natural streamflow for 1,385 streamgages in 19 study regions in the conterminous U.S. from October 1, 1980, through September 30, 2017. These estimates are provided for gages from mostly undisturbed watersheds as defined by Falcone (2011), using five statistical techniques: nearest-neighbor drainage area ratio (NNDAR), map-correlation drain
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Central Midwest Water Science Center

Statistical daily streamflow estimates at HUC12 outlets in the conterminous United States, Water Years 1981-2017

This data release contains daily time series estimates of natural streamflow at the outlets of more than 80,000 12-digit hydrologic units in 19 study regions across the conterminous U.S. from October 1, 1980 through September 30, 2017, using three statistical techniques: Nearest-Neighbor Drainage Area Ratio (NNDAR), Map-Correlation Drainage Area Ratio (MCDAR), and Ordinary Kriging of the logarithm
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Central Midwest Water Science Center

Model Input and Output for Hydrologic Simulations of the Southeastern United States for Historical and Future Conditions

This data release contains inputs for and outputs from hydrologic simulations of the southeastern U.S. using the Monthly Water Balance Model, the Precipitation Runoff Modeling System (PRMS), and statistically-based methods. These simulations were developed to provide estimates of water availability and statistics of streamflow for historical and potential future conditions for an area of approxima
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South Atlantic Water Science Center (SAWSC)

Water-quality trends and trend component estimates for the Nation's rivers and streams using Weighted Regressions on Time, Discharge, and Season (WRTDS) models and generalized flow normalization, 1972-2012

Nonstationary streamflow due to environmental and human-induced causes can affect water quality over time, yet these effects are poorly accounted for in water-quality trend models. This data release provides instream water-quality trends and estimates of two components of change, for sites across the Nation previously presented in Oelsner et al. (2017). We used previously calibrated Weighted Regre
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Lower Mississippi-Gulf Water Science Center

7Q10 Records and Basin Characteristics for 173 basins in Arkansas, Iowa, Kansas, Missouri, Nebraska, and Oklahoma (2017)

This data release replicates the methods detailed in the 2017 publication titled "Improving predictions of hydrological low-flow indices in ungaged basins using machine learning" for a different data set. The original data set and the associated readme file for the model archive can be viewed here: https://doi.org/10.5066/F7CR5S4T. The original data set contained streamflow data for sites located
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Lower Mississippi-Gulf Water Science Center

Streamflow, flow-duration curves, basin characteristics, and regression models of flow-duration curves for selected streamgages in the conterminous United States

This data release contains the input used and the output files interpreted in the publication 'Refinement of a Regression-Based Method for Prediction of Flow-Duration Curves of Daily Streamflow in the Conterminous United States'. This data release contains daily streamflow data for 1,378 streamgages in 19 study regions in the conterminous U.S. from October 1, 1980 through September 30, 2013 from m
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Central Midwest Water Science Center

Bias correction of Simulated Historical Daily Streamflow at Ungauged Locations Using Independently Estimated Flow-Duration Curves: Data Release

This dataset contains the observed and simulated streamflow used to produce the results of the journal article entitled Bias correction of Retrospective Simulation of Daily Streamflow at Ungauged Locations Using Independently Estimated Flow-Duration Curves . Observed streamflow, retrieved from the U.S. Geological Surveys National Water Information System (https://waterdata.usgs.gov/nwis) in Spring
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Water Resources Mission Area, Groundwater and Streamflow Information Program

Daily streamflow datasets used to analyze trends in streamflow at sites also analyzed for trends in water quality and ecological condition in the Nation's rivers and streams

In 1991, the U.S. Geological Survey (USGS) began a study of more than 50 major river basins across the Nation as part of the National Water-Quality Assessment (NAWQA) project of the National Water-Quality Program. One of the major goals of the NAWQA project is to determine how water-quality conditions change over time. To support that goal, long-term consistent and comparable monitoring has been c
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Water Resources Mission Area, National Water Quality Program

Characterizing Uncertainty in Daily Streamflow Estimates at Ungauged Locations in Support of the Massachusetts Sustainable Yield Estimator: Data Release

This data set archives all inputs, outputs and scripts needed to reproduce the findings of W.H. Farmer and S. Levin in the 2017 Journal of the American Water Resources Association article entitled Characterizing Uncertainty in Daily Streamflow Estimates at Ungauged Locations in Support of the Massachusetts Sustainable Yield Estimator. Input data includes observed streamflow values, in cubic feet
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Water Resources Mission Area

Geospatial Tools Effectively Estimate Nonexceedance Probabilities of Daily Streamflow at Ungaged and Intermittently Gaged Locations in Ohio: Data Release

This data set archives all inputs, outputs and scripts needed to reproduce the findings of W.H. Farmer and G.F. Koltun in the 2017 Journal of Hydrology Regional Studies article entitled Geospatial Tools Effectively Estimated Nonexceedance Probabilities of Daily Streamflow at Ungauged and Intermittently Gauged Locations in Ohio. Input data includes observed streamflow values, in cubic feet per seco
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Water Resources Mission Area

WREG: Weighted Least Squares Regression for Streamflow Frequency Statistics

Software package to support regression-based regionalization of streamflow frequency statistics that follow a log-Pearson type III distribution.
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Water Resources Mission Area

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