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Susan Wherry

Susan Wherry is a hydrologist at the USGS Oregon Water Science Center.

Science and Products

Predicting redox conditions in groundwater at a national scale using random forest classification

Redox conditions in groundwater may markedly affect the fate and transport of nutrients, volatile organic compounds, and trace metals, with significant implications for human health. While many local assessments of redox conditions have been made, the spatial variability of redox reaction rates makes the determination of redox conditions at regional or national scales problematic. In this study, r
Authors
Anthony J. Tesoriero, Susan Wherry, Danielle Dupuy, Tyler D. Johnson
By
Water Resources Mission Area, California Water Science Center, Oregon Water Science Center

Examining the effect of physicochemical and meteorological variables on water quality indicators of harmful algal blooms in a shallow hypereutrophic lake using machine learning techniques

Two independent machine learning techniques, boosted regression trees and artificial neural networks, were used to examine the physicochemical and meteorological variables that affect the seasonal growth and decline of harmful algal blooms (HABs) in a shallow, hypereutrophic lake in southern Oregon. High temporal resolution data collected at four monitoring locations were aggregated into daily tim
Authors
Susan Wherry, Liam N. Schenk
By
Water Resources Mission Area, Oregon Water Science Center

Future climate-induced changes in mixing and deep oxygen content of a caldera lake with hydrothermal heat and salt inputs

Vertical profiles of temperature, salinity and dissolved oxygen in Crater Lake, a caldera lake in the Oregon Cascade Range that receives hydrothermal inputs of heat and salt, were simulated with a 1-dimensional model. Twelve Global Circulation Models and two Representative Concentration Pathways (RCPs) were used to develop boundary conditions from 1950 to 2099. The model simulated the ventilation
Authors
Tamara M. Wood, Susan Wherry, Sebastiano Piccolroaz, Scott F Girdner
By
Water Resources Mission Area, Oregon Water Science Center

Modeling flow and water quality in reservoir and river reaches of the Mahoning River Basin, Ohio

Executive SummaryThe U.S. Army Corps of Engineers (USACE) is considering changes to the management of water surface elevation in four lakes in the Mahoning River Basin. These changes would affect the timing and amounts of water released to the Mahoning River and could affect the water quality of those releases. To provide information on possible water-quality effects from these operational changes
Authors
Annett B. Sullivan, Gabrielle M. Georgetson, Christina E. Urbanczyk, Gabriel W. Gordon, Susan A. Wherry, William B. Long
By
Water Resources Mission Area, Oregon Water Science Center

Summary of extreme water-quality conditions in Upper Klamath Lake, Oregon, 2005–19

This study used the complete set of continuous water-quality (WQ) data and discrete measurements of total ammonia collected by the U.S. Geological Survey from 2005 to 2019 at the four core sites in Upper Klamath Lake, Oregon, to examine relations between variables and extreme conditions that may be harmful for endemic Lost River suckers (Deltistes luxatus) and shortnose suckers (Chasmistes breviro
Authors
Susan A. Wherry
By
Water Resources Mission Area, Oregon Water Science Center

Factors affecting nitrate concentrations in stream base flow

Elevated nitrogen concentrations in streams and rivers in the Chesapeake Bay watershed have adversely affected the ecosystem health of the bay. Much of this nitrogen is derived as nitrate from groundwater that discharges to streams as base flow. In this study, boosted regression trees (BRTs) were used to relate nitrate concentrations in base flow (n = 156) to explanatory variables describing nitro
Authors
Susan Wherry, Anthony J. Tesoriero, Silvia Terziotti
By
Water Resources Mission Area, Chesapeake Bay Activities, Oregon Water Science Center

Assessment of Columbia and Willamette River flood stage on the Columbia Corridor Levee System at Portland, Oregon, in a future climate

To support Levee Ready Columbia’s (LRC’s) effort to re-certify levees along the Columbia and Willamette Rivers and remain accredited, two 2-dimensional hydraulic models, Adaptive Hydraulics and Delft3D-Flexible Mesh, were used to simulate the effects of plausible extreme high water during the 2030 to 2059 period. The Columbia River was simulated from Bonneville Dam, situated at river mile (RM) 145
Authors
Susan A. Wherry, Tamara M. Wood, Hans R. Moritz, Keith B. Duffy
By
Water Resources Mission Area, Oregon Water Science Center

A metabolism-based whole lake eutrophication model to estimate the magnitude and time scales of the effects of restoration in Upper Klamath Lake, south-central Oregon

A whole lake eutrophication (WLE) model approach for phosphorus and cyanobacterial biomass in Upper Klamath Lake, south-central Oregon, is presented here. The model is a successor to a previous model developed to inform a Total Maximum Daily Load (TMDL) for phosphorus in the lake, but is based on net primary production (NPP), which can be calculated from dissolved oxygen, rather than scaling up a
Authors
Susan A. Wherry, Tamara M. Wood
By
Water Resources Mission Area, Oregon Water Science Center

Comparison of mercury mass loading in streams to atmospheric deposition in watersheds of Western North America: Evidence for non-atmospheric mercury sources

Annual stream loads of mercury (Hg) and inputs of wet and dry atmospheric Hg deposition to the landscape were investigated in watersheds of the Western United States and the Canadian-Alaskan Arctic. Mercury concentration and discharge data from flow gauging stations were used to compute annual mass loads with regression models. Measured wet and modeled dry deposition were compared to annual stream
Authors
Joseph L. Domagalski, Michael S. Majewski, Charles N. Alpers, Chris S. Eckley, Collin A. Eagles-Smith, Liam N. Schenk, Susan Wherry
By
Ecosystems Mission Area, Water Resources Mission Area, Contaminant Biology, Environmental Health Program, California Water Science Center, Forest and Rangeland Ecosystem Science Center, John Wesley Powell Center for Analysis and Synthesis

Simulation of deep ventilation in Crater Lake, Oregon, 1951–2099

The frequency of deep ventilation events in Crater Lake, a caldera lake in the Oregon Cascade Mountains, was simulated in six future climate scenarios, using a 1-dimensional deep ventilation model (1DDV) that was developed to simulate the ventilation of deep water initiated by reverse stratification and subsequent thermobaric instability. The model was calibrated and validated with lake temperatur

Authors
Tamara M. Wood, Susan A. Wherry, Sebastiano Piccolroaz, Scott F Girdner
By
Water Resources Mission Area, Oregon Water Science Center, Crater Lake

Revision and proposed modification for a total maximum daily load model for Upper Klamath Lake, Oregon

This report presents Phase 2 of the review and development of the mass balance water-quality model, originally developed in 2001, that guided establishment of the phosphorus (P) total maximum daily load (TMDL) for Upper Klamath and Agency Lakes, Oregon. The purpose of Phase 2 was to incorporate a longer (19-year) set of external phosphorus loading data into the lake TMDL model than had originally
Authors
Susan A. Wherry, Tamara M. Wood, Chauncey W. Anderson
By
Water Resources Mission Area, Oregon Water Science Center
link
boat on bank of Columbia River

Future Climate Effects on Columbia and Willamette River Levees

USGS research directly helps local public agencies that are responsible for the design and maintenance of the levees that surround the northern Portland metropolitan area with the goal of protecting life and property in the event of flooding from the Columbia and Willamette Rivers that surround the city.
By
Oregon Water Science Center
link

Future Climate Effects on Columbia and Willamette River Levees

USGS research directly helps local public agencies that are responsible for the design and maintenance of the levees that surround the northern Portland metropolitan area with the goal of protecting life and property in the event of flooding from the Columbia and Willamette Rivers that surround the city.
Learn More
link
USGS scientist collecting samples at Crater Lake, Oregon

Future Water Clarity and Dissolved Oxygen in Crater Lake

Warming air temperature may change water temperature and water column mixing in Oregon’s Crater Lake over the next several decades, potentially impacting the clarity and health of the iconic lake.
By
Oregon Water Science Center
link

Future Water Clarity and Dissolved Oxygen in Crater Lake

Warming air temperature may change water temperature and water column mixing in Oregon’s Crater Lake over the next several decades, potentially impacting the clarity and health of the iconic lake.
Learn More

Input and results from a random forest classification (RFC) model that predicts redox conditions in groundwater in the contiguous United States

This data release provides model inputs and outputs for a model that predicts redox conditions in groundwater in the contiguous United States. Input variables describe the hydrology, soils, geology, and hydrologic position of groundwater sample locations. The data release accompanies a journal article that describes model development and applications (Tesoriero_and_others_2023).
By
Oregon Water Science Center

Input and results from boosted regression tree and artificial neural network models that predict daily maximum pH and daily minimum dissolved oxygen in Upper Klamath Lake, 2005-2019

This data release contains the model inputs, outputs, and source code (written in R) for the boosted regression tree (BRT) and artificial neural network (ANN) models developed for four sites in Upper Klamath Lake which were used to simulate daily maximum pH and daily minimum dissolved oxygen (DO) from May 18th to October 4th in 2005-12 and 2015-19 at four sites, and to evaluate variable effects an
By
Oregon Water Science Center

1-D Deep Ventilation (1DDV) model for Crater Lake, Oregon, 1950-2100

This data release contains the source code for the 1-D Deep Ventilation (1DDV) model (written in the Matlab programming language), and the input and output data from that model that were used to simulate temperature, salinity, and dissolved oxygen (DO) at specific depths in the lake. The input data consisted of: 1. daily average surface water temperature either a. collected by thermistors (Crawfor
By
Oregon Water Science Center

Water quality measurements in off-channel water bodies of the Willamette River near Albany and Keizer, OR (2017 and 2019)

The tabular data sets and associated maps in this data release represent water-quality data that were collected between April and November of 2017 and between July and November of 2019 to describe baseline conditions prior to or sometimes following treatments using herbicides or other methods to reduce the biomass of non-native water primrose (Ludwigia) within off-channel water bodies of the Willa
By
Oregon Water Science Center

Hydrodynamic model of the lower Columbia River, Washington and Oregon, 2017-2020

A three-dimensional hydrodynamic model of the lower Columbia River (LCR) was constructed using the Delft3D Flexible Mesh (DFM) modeling suite to simulate water levels, flow, and seabed stresses between January 1, 2017, and April 20, 2020. This data release describes the construction and validation of the model application and provides input files suitable to run the model on Delft3D Flexible Mesh
By
Coastal and Marine Hazards and Resources Program, Pacific Coastal and Marine Science Center

Input and results from a boosted regression tree (BRT) model relating base flow nitrate concentrations in the Chesapeake Bay watershed to catchment characteristics (1970-2013)

This data release contains a boosted regression tree (BRT) model (written in the R programming language), and the input and output data from that model that were used to relate base flow nitrate concentrations in the Chesapeake Bay watershed to catchment characteristics. The input data consists of two types of information: 1) surface water nitrate concentrations collected by the USGS and partnerin
By
Chesapeake Bay Activities, Oregon Water Science Center
Models examine how climate change may affect Oregon's Crater Lake

Models examine how climate change may affect Oregon's Crater Lake

How will climate change affect deep water mixing in Crater Lake? 

Read Article
New USGS study identifies key factors affecting nitrate concentrations in stream base flow in Chesapeake Bay watershed

New USGS study identifies key factors affecting nitrate concentrations in stream base flow in Chesapeake Bay watershed

A new USGS study has identified factors that contribute to high nitrate in base flow in streams flowing into Chesapeake Bay. Land use, organic carbon...

Read Article

Science and Products

Predicting redox conditions in groundwater at a national scale using random forest classification

Redox conditions in groundwater may markedly affect the fate and transport of nutrients, volatile organic compounds, and trace metals, with significant implications for human health. While many local assessments of redox conditions have been made, the spatial variability of redox reaction rates makes the determination of redox conditions at regional or national scales problematic. In this study, r
Authors
Anthony J. Tesoriero, Susan Wherry, Danielle Dupuy, Tyler D. Johnson
By
Water Resources Mission Area, California Water Science Center, Oregon Water Science Center

Examining the effect of physicochemical and meteorological variables on water quality indicators of harmful algal blooms in a shallow hypereutrophic lake using machine learning techniques

Two independent machine learning techniques, boosted regression trees and artificial neural networks, were used to examine the physicochemical and meteorological variables that affect the seasonal growth and decline of harmful algal blooms (HABs) in a shallow, hypereutrophic lake in southern Oregon. High temporal resolution data collected at four monitoring locations were aggregated into daily tim
Authors
Susan Wherry, Liam N. Schenk
By
Water Resources Mission Area, Oregon Water Science Center

Future climate-induced changes in mixing and deep oxygen content of a caldera lake with hydrothermal heat and salt inputs

Vertical profiles of temperature, salinity and dissolved oxygen in Crater Lake, a caldera lake in the Oregon Cascade Range that receives hydrothermal inputs of heat and salt, were simulated with a 1-dimensional model. Twelve Global Circulation Models and two Representative Concentration Pathways (RCPs) were used to develop boundary conditions from 1950 to 2099. The model simulated the ventilation
Authors
Tamara M. Wood, Susan Wherry, Sebastiano Piccolroaz, Scott F Girdner
By
Water Resources Mission Area, Oregon Water Science Center

Modeling flow and water quality in reservoir and river reaches of the Mahoning River Basin, Ohio

Executive SummaryThe U.S. Army Corps of Engineers (USACE) is considering changes to the management of water surface elevation in four lakes in the Mahoning River Basin. These changes would affect the timing and amounts of water released to the Mahoning River and could affect the water quality of those releases. To provide information on possible water-quality effects from these operational changes
Authors
Annett B. Sullivan, Gabrielle M. Georgetson, Christina E. Urbanczyk, Gabriel W. Gordon, Susan A. Wherry, William B. Long
By
Water Resources Mission Area, Oregon Water Science Center

Summary of extreme water-quality conditions in Upper Klamath Lake, Oregon, 2005–19

This study used the complete set of continuous water-quality (WQ) data and discrete measurements of total ammonia collected by the U.S. Geological Survey from 2005 to 2019 at the four core sites in Upper Klamath Lake, Oregon, to examine relations between variables and extreme conditions that may be harmful for endemic Lost River suckers (Deltistes luxatus) and shortnose suckers (Chasmistes breviro
Authors
Susan A. Wherry
By
Water Resources Mission Area, Oregon Water Science Center

Factors affecting nitrate concentrations in stream base flow

Elevated nitrogen concentrations in streams and rivers in the Chesapeake Bay watershed have adversely affected the ecosystem health of the bay. Much of this nitrogen is derived as nitrate from groundwater that discharges to streams as base flow. In this study, boosted regression trees (BRTs) were used to relate nitrate concentrations in base flow (n = 156) to explanatory variables describing nitro
Authors
Susan Wherry, Anthony J. Tesoriero, Silvia Terziotti
By
Water Resources Mission Area, Chesapeake Bay Activities, Oregon Water Science Center

Assessment of Columbia and Willamette River flood stage on the Columbia Corridor Levee System at Portland, Oregon, in a future climate

To support Levee Ready Columbia’s (LRC’s) effort to re-certify levees along the Columbia and Willamette Rivers and remain accredited, two 2-dimensional hydraulic models, Adaptive Hydraulics and Delft3D-Flexible Mesh, were used to simulate the effects of plausible extreme high water during the 2030 to 2059 period. The Columbia River was simulated from Bonneville Dam, situated at river mile (RM) 145
Authors
Susan A. Wherry, Tamara M. Wood, Hans R. Moritz, Keith B. Duffy
By
Water Resources Mission Area, Oregon Water Science Center

A metabolism-based whole lake eutrophication model to estimate the magnitude and time scales of the effects of restoration in Upper Klamath Lake, south-central Oregon

A whole lake eutrophication (WLE) model approach for phosphorus and cyanobacterial biomass in Upper Klamath Lake, south-central Oregon, is presented here. The model is a successor to a previous model developed to inform a Total Maximum Daily Load (TMDL) for phosphorus in the lake, but is based on net primary production (NPP), which can be calculated from dissolved oxygen, rather than scaling up a
Authors
Susan A. Wherry, Tamara M. Wood
By
Water Resources Mission Area, Oregon Water Science Center

Comparison of mercury mass loading in streams to atmospheric deposition in watersheds of Western North America: Evidence for non-atmospheric mercury sources

Annual stream loads of mercury (Hg) and inputs of wet and dry atmospheric Hg deposition to the landscape were investigated in watersheds of the Western United States and the Canadian-Alaskan Arctic. Mercury concentration and discharge data from flow gauging stations were used to compute annual mass loads with regression models. Measured wet and modeled dry deposition were compared to annual stream
Authors
Joseph L. Domagalski, Michael S. Majewski, Charles N. Alpers, Chris S. Eckley, Collin A. Eagles-Smith, Liam N. Schenk, Susan Wherry
By
Ecosystems Mission Area, Water Resources Mission Area, Contaminant Biology, Environmental Health Program, California Water Science Center, Forest and Rangeland Ecosystem Science Center, John Wesley Powell Center for Analysis and Synthesis

Simulation of deep ventilation in Crater Lake, Oregon, 1951–2099

The frequency of deep ventilation events in Crater Lake, a caldera lake in the Oregon Cascade Mountains, was simulated in six future climate scenarios, using a 1-dimensional deep ventilation model (1DDV) that was developed to simulate the ventilation of deep water initiated by reverse stratification and subsequent thermobaric instability. The model was calibrated and validated with lake temperatur

Authors
Tamara M. Wood, Susan A. Wherry, Sebastiano Piccolroaz, Scott F Girdner
By
Water Resources Mission Area, Oregon Water Science Center, Crater Lake

Revision and proposed modification for a total maximum daily load model for Upper Klamath Lake, Oregon

This report presents Phase 2 of the review and development of the mass balance water-quality model, originally developed in 2001, that guided establishment of the phosphorus (P) total maximum daily load (TMDL) for Upper Klamath and Agency Lakes, Oregon. The purpose of Phase 2 was to incorporate a longer (19-year) set of external phosphorus loading data into the lake TMDL model than had originally
Authors
Susan A. Wherry, Tamara M. Wood, Chauncey W. Anderson
By
Water Resources Mission Area, Oregon Water Science Center
link
boat on bank of Columbia River

Future Climate Effects on Columbia and Willamette River Levees

USGS research directly helps local public agencies that are responsible for the design and maintenance of the levees that surround the northern Portland metropolitan area with the goal of protecting life and property in the event of flooding from the Columbia and Willamette Rivers that surround the city.
By
Oregon Water Science Center
link

Future Climate Effects on Columbia and Willamette River Levees

USGS research directly helps local public agencies that are responsible for the design and maintenance of the levees that surround the northern Portland metropolitan area with the goal of protecting life and property in the event of flooding from the Columbia and Willamette Rivers that surround the city.
Learn More
link
USGS scientist collecting samples at Crater Lake, Oregon

Future Water Clarity and Dissolved Oxygen in Crater Lake

Warming air temperature may change water temperature and water column mixing in Oregon’s Crater Lake over the next several decades, potentially impacting the clarity and health of the iconic lake.
By
Oregon Water Science Center
link

Future Water Clarity and Dissolved Oxygen in Crater Lake

Warming air temperature may change water temperature and water column mixing in Oregon’s Crater Lake over the next several decades, potentially impacting the clarity and health of the iconic lake.
Learn More

Input and results from a random forest classification (RFC) model that predicts redox conditions in groundwater in the contiguous United States

This data release provides model inputs and outputs for a model that predicts redox conditions in groundwater in the contiguous United States. Input variables describe the hydrology, soils, geology, and hydrologic position of groundwater sample locations. The data release accompanies a journal article that describes model development and applications (Tesoriero_and_others_2023).
By
Oregon Water Science Center

Input and results from boosted regression tree and artificial neural network models that predict daily maximum pH and daily minimum dissolved oxygen in Upper Klamath Lake, 2005-2019

This data release contains the model inputs, outputs, and source code (written in R) for the boosted regression tree (BRT) and artificial neural network (ANN) models developed for four sites in Upper Klamath Lake which were used to simulate daily maximum pH and daily minimum dissolved oxygen (DO) from May 18th to October 4th in 2005-12 and 2015-19 at four sites, and to evaluate variable effects an
By
Oregon Water Science Center

1-D Deep Ventilation (1DDV) model for Crater Lake, Oregon, 1950-2100

This data release contains the source code for the 1-D Deep Ventilation (1DDV) model (written in the Matlab programming language), and the input and output data from that model that were used to simulate temperature, salinity, and dissolved oxygen (DO) at specific depths in the lake. The input data consisted of: 1. daily average surface water temperature either a. collected by thermistors (Crawfor
By
Oregon Water Science Center

Water quality measurements in off-channel water bodies of the Willamette River near Albany and Keizer, OR (2017 and 2019)

The tabular data sets and associated maps in this data release represent water-quality data that were collected between April and November of 2017 and between July and November of 2019 to describe baseline conditions prior to or sometimes following treatments using herbicides or other methods to reduce the biomass of non-native water primrose (Ludwigia) within off-channel water bodies of the Willa
By
Oregon Water Science Center

Hydrodynamic model of the lower Columbia River, Washington and Oregon, 2017-2020

A three-dimensional hydrodynamic model of the lower Columbia River (LCR) was constructed using the Delft3D Flexible Mesh (DFM) modeling suite to simulate water levels, flow, and seabed stresses between January 1, 2017, and April 20, 2020. This data release describes the construction and validation of the model application and provides input files suitable to run the model on Delft3D Flexible Mesh
By
Coastal and Marine Hazards and Resources Program, Pacific Coastal and Marine Science Center

Input and results from a boosted regression tree (BRT) model relating base flow nitrate concentrations in the Chesapeake Bay watershed to catchment characteristics (1970-2013)

This data release contains a boosted regression tree (BRT) model (written in the R programming language), and the input and output data from that model that were used to relate base flow nitrate concentrations in the Chesapeake Bay watershed to catchment characteristics. The input data consists of two types of information: 1) surface water nitrate concentrations collected by the USGS and partnerin
By
Chesapeake Bay Activities, Oregon Water Science Center
Models examine how climate change may affect Oregon's Crater Lake

Models examine how climate change may affect Oregon's Crater Lake

How will climate change affect deep water mixing in Crater Lake? 

Read Article
New USGS study identifies key factors affecting nitrate concentrations in stream base flow in Chesapeake Bay watershed

New USGS study identifies key factors affecting nitrate concentrations in stream base flow in Chesapeake Bay watershed

A new USGS study has identified factors that contribute to high nitrate in base flow in streams flowing into Chesapeake Bay. Land use, organic carbon...

Read Article
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