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• 1. [Article] Laurance Lake Temperature Model

  Laurance Lake is a reservoir located in Hood River County, Oregon (Figure 1). It is located at the base on Mt. Hood in Oregon (see Figure 2 and Figure 3), discharges into the Middle Fork of the Hood River. ...

  Citation × Citation Citation Abstract Copy Title: Laurance Lake Temperature Model Author: Berger, Chris, Wells, Scott A., Annear, Robert Leslie Year: 2005 Laurance Lake is a reservoir located in Hood River County, Oregon (Figure 1). It is located at the base on Mt. Hood in Oregon (see Figure 2 and Figure 3), discharges into the Middle Fork of the Hood River. The reservoir was constructed in 1968 for irrigation storage and has a capacity 3564 acre- feet at full pool. Since the river vio lates temperature standards, this study has been designed to construct a hydrodynamic and temperature model of Laurance reservoir in order to assess strategies for improving temperatures in the Middle Fork River. The objectives of the study are then to Develop a hydrodynamic and temperature model of Laurance Lake Calibrate the model to field data collected from November 2002 through Spring 2004 Use the model to evaluate strategies for temperature improvement through operational or structural changes to Lake Laurance The model chosen for development was CE-QUAL-W2 Version 3.2 (Cole and Wells, 2004). This is a two-dimensional unsteady hydrodynamic, temperature and water quality model that includes typical eutrophication parameters (algae, nutrients, temperature, organic matter, dissolved oxygen, pH). PSU, under the support of the Corps of Engineers Waterways Experiment Station, is a center for development of this modeling tool. Title: Laurance Lake Temperature Model Author: Berger, Chris, Wells, Scott A., Annear, Robert Leslie Year: 2005 Laurance Lake is a reservoir located in Hood River County, Oregon (Figure 1). It is located at the base on Mt. Hood in Oregon (see Figure 2 and Figure 3), discharges into the Middle Fork of the Hood River. The reservoir was constructed in 1968 for irrigation storage and has a capacity 3564 acre- feet at full pool. Since the river vio lates temperature standards, this study has been designed to construct a hydrodynamic and temperature model of Laurance reservoir in order to assess strategies for improving temperatures in the Middle Fork River. The objectives of the study are then to Develop a hydrodynamic and temperature model of Laurance Lake Calibrate the model to field data collected from November 2002 through Spring 2004 Use the model to evaluate strategies for temperature improvement through operational or structural changes to Lake Laurance The model chosen for development was CE-QUAL-W2 Version 3.2 (Cole and Wells, 2004). This is a two-dimensional unsteady hydrodynamic, temperature and water quality model that includes typical eutrophication parameters (algae, nutrients, temperature, organic matter, dissolved oxygen, pH). PSU, under the support of the Corps of Engineers Waterways Experiment Station, is a center for development of this modeling tool. Close

• 2. [Article] Estimation of Surface Water Temperature of the Tigris River System in Iraq

  Monitoring surface water temperatures (Tw) in lakes, rivers, and reservoirs is a key component of environmental management and influences water quality by affecting bio-geo chemical reaction rates, altering ...

  Citation × Citation Citation Abstract Copy Title: Estimation of Surface Water Temperature of the Tigris River System in Iraq Author: Al-Murib, M., Wells, Scott A., Talke, Stefan A. Year: 2017 Monitoring surface water temperatures (Tw) in lakes, rivers, and reservoirs is a key component of environmental management and influences water quality by affecting bio-geo chemical reaction rates, altering the saturation concentration of dissolved oxygen (DO), and influencing the susceptibility of fish to disease. Temperatures in the Tigris River, one of the largest rivers in the Middle East, are influenced by factors such as heat fluxes at the air-water and human activities such as direct discharge of water to the river. However, modeling and management of water temperature is limited by a paucity of in-situ data, which prevents calibration of models. In this study, we infill data gaps by estimating Tw using the thermal bands of both the Landsat 5 TM and Landsat 7 ETM+ sensors. These satellite-based estimates, typically measured once or twice a month with 60-120m resolution, are then used to develop a regression model that relates daily water temperature to daily air temperature and river flow. These estimates are used to define the Tw boundary conditions for a hydrodynamic and water quality model of the Tigris River based on a 2D implementation of the CE-QUAL-W2 (W2) numerical model. Initial results suggest that there is a significant agreement between modeled and remotely estimated data of Tw. Results suggest that short-wave solar radiation is the most important factor that controls seasonal Tw variations. However, anthropogenic influence is observed as a result of return irrigation flows and flows from Tharthar Lake. Title: Estimation of Surface Water Temperature of the Tigris River System in Iraq Author: Al-Murib, M., Wells, Scott A., Talke, Stefan A. Year: 2017 Monitoring surface water temperatures (Tw) in lakes, rivers, and reservoirs is a key component of environmental management and influences water quality by affecting bio-geo chemical reaction rates, altering the saturation concentration of dissolved oxygen (DO), and influencing the susceptibility of fish to disease. Temperatures in the Tigris River, one of the largest rivers in the Middle East, are influenced by factors such as heat fluxes at the air-water and human activities such as direct discharge of water to the river. However, modeling and management of water temperature is limited by a paucity of in-situ data, which prevents calibration of models. In this study, we infill data gaps by estimating Tw using the thermal bands of both the Landsat 5 TM and Landsat 7 ETM+ sensors. These satellite-based estimates, typically measured once or twice a month with 60-120m resolution, are then used to develop a regression model that relates daily water temperature to daily air temperature and river flow. These estimates are used to define the Tw boundary conditions for a hydrodynamic and water quality model of the Tigris River based on a 2D implementation of the CE-QUAL-W2 (W2) numerical model. Initial results suggest that there is a significant agreement between modeled and remotely estimated data of Tw. Results suggest that short-wave solar radiation is the most important factor that controls seasonal Tw variations. However, anthropogenic influence is observed as a result of return irrigation flows and flows from Tharthar Lake. Close

• 3. [Article] Modeling Effects of Channel Complexity and Hyporheic Flow on Stream Temperatures

  Stream temperatures are affected by multiple forcing functions, including surface heat exchange (including solar radiation, evaporation, conduction, and net long wave radiation) and hyporheic flows. Each ...

  Citation × Citation Citation Abstract Copy Title: Modeling Effects of Channel Complexity and Hyporheic Flow on Stream Temperatures Author: Berger, Chris, Wells, Scott A. Year: 2007 Stream temperatures are affected by multiple forcing functions, including surface heat exchange (including solar radiation, evaporation, conduction, and net long wave radiation) and hyporheic flows. Each of these forcing functions is directly influenced by the level of channel complexity in the stream channel and riparian shading. The interrelationship between channel complexity, hyporheic flow and stream temperature is highly complex, and efforts to manage for habitat diversity by managing channel complexity could result in unintended consequences on stream temperature. When planning modifications to stream channel complexity, consideration should be given to the effects such moderations could have on stream temperatures. Urbanization has impacted many steams due to the construction of bank protections, levees, vegetation removal, etc. Such activities have eliminated side channels and reduced stream braiding, thereby reducing the overall channel complexity. Hulse et al. (2002) developed maps showing the channel configurations of the Willamette River in Oregon, USA in the years 1850 and 1995. These maps show a significant reduction in channel complexity in the intervening years. More complex stream channels provide greater habitat diversity and thus, are generally more desirable from a wildlife management perspective. Therefore, management of streams for increased channel complexity is gaining in popularity. Knowing that stream channel complexity has diminished over time, an important question to consider is ‘what were stream temperatures before we altered the natural channels?’ This is an important issue in determining what natural conditions were and how we have strayed from these so-called ‘natural’ conditions as a result of channelization, dam building, and changes to the riparian vegetation and deforestation. Current Total Maximum Daily Load’s (TMDL) rely on determining a ‘natural’ condition. In order to develop an understanding of what that is, a hydrodynamic and water quality computer simulation model has been applied to Oregon’s Willamette River with several levels of channel complexity and varying rates of hyporheic flows. Adapting the model used to develop TMDL’s for temperature in the Willamette River, the effects of present and past channel complexity on water temperatures was determined. The model used to develop the TMDL was the U. S. Army Corps of Engineers dynamic 2-D model CE-QUAL-W2, which consists of directly coupled hydrodynamic and water quality transport models and simulates parameters such as temperature, algae concentration, dissolved oxygen concentration, pH, nutrient concentrations and residence time. The model also incorporates a dynamic shading algorithm for both vegetative and topographic shading on water bodies. Title: Modeling Effects of Channel Complexity and Hyporheic Flow on Stream Temperatures Author: Berger, Chris, Wells, Scott A. Year: 2007 Stream temperatures are affected by multiple forcing functions, including surface heat exchange (including solar radiation, evaporation, conduction, and net long wave radiation) and hyporheic flows. Each of these forcing functions is directly influenced by the level of channel complexity in the stream channel and riparian shading. The interrelationship between channel complexity, hyporheic flow and stream temperature is highly complex, and efforts to manage for habitat diversity by managing channel complexity could result in unintended consequences on stream temperature. When planning modifications to stream channel complexity, consideration should be given to the effects such moderations could have on stream temperatures. Urbanization has impacted many steams due to the construction of bank protections, levees, vegetation removal, etc. Such activities have eliminated side channels and reduced stream braiding, thereby reducing the overall channel complexity. Hulse et al. (2002) developed maps showing the channel configurations of the Willamette River in Oregon, USA in the years 1850 and 1995. These maps show a significant reduction in channel complexity in the intervening years. More complex stream channels provide greater habitat diversity and thus, are generally more desirable from a wildlife management perspective. Therefore, management of streams for increased channel complexity is gaining in popularity. Knowing that stream channel complexity has diminished over time, an important question to consider is ‘what were stream temperatures before we altered the natural channels?’ This is an important issue in determining what natural conditions were and how we have strayed from these so-called ‘natural’ conditions as a result of channelization, dam building, and changes to the riparian vegetation and deforestation. Current Total Maximum Daily Load’s (TMDL) rely on determining a ‘natural’ condition. In order to develop an understanding of what that is, a hydrodynamic and water quality computer simulation model has been applied to Oregon’s Willamette River with several levels of channel complexity and varying rates of hyporheic flows. Adapting the model used to develop TMDL’s for temperature in the Willamette River, the effects of present and past channel complexity on water temperatures was determined. The model used to develop the TMDL was the U. S. Army Corps of Engineers dynamic 2-D model CE-QUAL-W2, which consists of directly coupled hydrodynamic and water quality transport models and simulates parameters such as temperature, algae concentration, dissolved oxygen concentration, pH, nutrient concentrations and residence time. The model also incorporates a dynamic shading algorithm for both vegetative and topographic shading on water bodies. Close

• 4. [Article] Hydrodynamic and Water Quality Modeling of the Chehalis River in Washington

  The Chehalis River Basin is located in the southwest region of Washington and is over 125 miles long flowing through agricultural, residential, industrial, and forest land. Four major rivers, many smaller ...

  Citation × Citation Citation Abstract Copy Title: Hydrodynamic and Water Quality Modeling of the Chehalis River in Washington Author: Van Glubt, Sarah, Wells, Scott A., Berger, Chris J. Year: 2017 The Chehalis River Basin is located in the southwest region of Washington and is over 125 miles long flowing through agricultural, residential, industrial, and forest land. Four major rivers, many smaller creeks, five wastewater treatment plants, and groundwater discharge to the Chehalis River. Flooding is a major problem in the relatively flat areas surrounding the cities of Chehalis and Centralia. As a result, construction of a flood-control dam in the upper basin has been proposed. One major concern of constructing a dam is the potentially severe impacts to fish health and habitat. The Chehalis River has routinely violated water quality standards for primarily temperature and dissolved oxygen. CE-QUAL-W2, a two-dimensional (longitudinal and vertical) hydrodynamic and water quality model, was used to simulate the Chehalis River, including free flowing river stretches and stratified (in summer) lake-like stretches. The goals of this research were to assess the flood retention structure’s impacts to water quality, as well as river responses to potential climate change scenarios. In order to use the model to achieve these goals, calibration to field data for flow, temperature, and water quality constituents was performed for the years 2013 and 2014. Once calibration was complete, model scenarios for future climate conditions and dam operating regimes were conducted. Future conditions showed predictions of warmer water temperatures and slight changes to water quality conditions on the river. As fish in the area prefer cooler water temperatures, this could pose a threat to fish health and habitat. Flood retention structures with the purpose of flood retention only (only operating during times of flooding) gave model predictions for daily maximum temperature higher than structures that employed flood retention and flow augmentation (operating during all times of the year). This suggested the management of flow passage or retention by the dam is important for water quality on the river. Title: Hydrodynamic and Water Quality Modeling of the Chehalis River in Washington Author: Van Glubt, Sarah, Wells, Scott A., Berger, Chris J. Year: 2017 The Chehalis River Basin is located in the southwest region of Washington and is over 125 miles long flowing through agricultural, residential, industrial, and forest land. Four major rivers, many smaller creeks, five wastewater treatment plants, and groundwater discharge to the Chehalis River. Flooding is a major problem in the relatively flat areas surrounding the cities of Chehalis and Centralia. As a result, construction of a flood-control dam in the upper basin has been proposed. One major concern of constructing a dam is the potentially severe impacts to fish health and habitat. The Chehalis River has routinely violated water quality standards for primarily temperature and dissolved oxygen. CE-QUAL-W2, a two-dimensional (longitudinal and vertical) hydrodynamic and water quality model, was used to simulate the Chehalis River, including free flowing river stretches and stratified (in summer) lake-like stretches. The goals of this research were to assess the flood retention structure’s impacts to water quality, as well as river responses to potential climate change scenarios. In order to use the model to achieve these goals, calibration to field data for flow, temperature, and water quality constituents was performed for the years 2013 and 2014. Once calibration was complete, model scenarios for future climate conditions and dam operating regimes were conducted. Future conditions showed predictions of warmer water temperatures and slight changes to water quality conditions on the river. As fish in the area prefer cooler water temperatures, this could pose a threat to fish health and habitat. Flood retention structures with the purpose of flood retention only (only operating during times of flooding) gave model predictions for daily maximum temperature higher than structures that employed flood retention and flow augmentation (operating during all times of the year). This suggested the management of flow passage or retention by the dam is important for water quality on the river. Close

• 5. [Article] Willamette River Basin Temperature TMDL Model: Model Calibration

  The State of Oregon Department of Environmental Quality (DEQ) is developing a TMDL for temperature in the Willamette River basin shown in Figure 1. The study area included the Willamette River and all ...

  Citation × Citation Citation Abstract Copy Title: Willamette River Basin Temperature TMDL Model: Model Calibration Author: Berger, Chris, McKillip, Michael Lee, Annear, Robert Leslie, Khan, Sher Jamal, Wells, Scott A. Year: 2004 The State of Oregon Department of Environmental Quality (DEQ) is developing a TMDL for temperature in the Willamette River basin shown in Figure 1. The study area included the Willamette River and all major tributaries (except the Tualatin River where a TMDL process was already concluded). A large section of the Columbia River was also modeled to provide adequate boundary representation of tidal flows in the lower Willamette River. The Willamette River below the Oregon City Falls in the Portland metropolitan area has a typical diurnal tidal range of 1 m. The development of a dynamic model of temperature and hydrodynamics of the entire river basin incorporating shading were primary requirements of this modeling study. The model would be used by DEQ to set temperature limits on point source dischargers and to evaluate the impact of management strategies on river temperatures to improve fish habitat. Some of these strategies included modifications of the dam at the Willamette River Falls south of Portland and channel reconfigurations. The river basin model was originally divided into several reaches. Individual models were developed for each reach. The models were set-up for each section of the Willamette basin as described in Annear et al. (2004a), the models were calibrated to field data and management strategies were evaluated as described in Annear et al (2004b). This report outlines the model calibration of each of these model sections or elements for both the calibration time periods. The calibration period for each model section differs due to the availability of boundary condition data. The model management simulation scenarios (Annear et al, 2004b) also required boundary condition data that extended past the calibration periods. Title: Willamette River Basin Temperature TMDL Model: Model Calibration Author: Berger, Chris, McKillip, Michael Lee, Annear, Robert Leslie, Khan, Sher Jamal, Wells, Scott A. Year: 2004 The State of Oregon Department of Environmental Quality (DEQ) is developing a TMDL for temperature in the Willamette River basin shown in Figure 1. The study area included the Willamette River and all major tributaries (except the Tualatin River where a TMDL process was already concluded). A large section of the Columbia River was also modeled to provide adequate boundary representation of tidal flows in the lower Willamette River. The Willamette River below the Oregon City Falls in the Portland metropolitan area has a typical diurnal tidal range of 1 m. The development of a dynamic model of temperature and hydrodynamics of the entire river basin incorporating shading were primary requirements of this modeling study. The model would be used by DEQ to set temperature limits on point source dischargers and to evaluate the impact of management strategies on river temperatures to improve fish habitat. Some of these strategies included modifications of the dam at the Willamette River Falls south of Portland and channel reconfigurations. The river basin model was originally divided into several reaches. Individual models were developed for each reach. The models were set-up for each section of the Willamette basin as described in Annear et al. (2004a), the models were calibrated to field data and management strategies were evaluated as described in Annear et al (2004b). This report outlines the model calibration of each of these model sections or elements for both the calibration time periods. The calibration period for each model section differs due to the availability of boundary condition data. The model management simulation scenarios (Annear et al, 2004b) also required boundary condition data that extended past the calibration periods. Close

• 6. [Article] Willamette River Basin Temperature TMDL Model: Model Scenarios

  The State of Oregon Department of Environmental Quality (DEQ) is developing a TMDL for temperature in the Willamette River basin shown in Figure 1. The study area included the Willamette River and all ...

  Citation × Citation Citation Abstract Copy Title: Willamette River Basin Temperature TMDL Model: Model Scenarios Author: Annear, Robert Leslie, McKillip, Michael Lee, Khan, Sher Jamal, Berger, Chris, Wells, Scott A. Year: 2004 The State of Oregon Department of Environmental Quality (DEQ) is developing a TMDL for temperature in the Willamette River basin shown in Figure 1. The study area included the Willamette River and all major tributaries (except the Tualatin River where a TMDL process was already concluded). A large section of the Columbia River was also modeled to provide adequate boundary representation of tidal flows in the lower Willamette River. The Willamette River below the Oregon City Falls in the Portland metropolitan area has a typical diurnal tidal range of 1 m. The development of a dynamic model of temperature and hydrodynamics of the entire river basin incorporating shading were primary requirements of this modeling study. The model would be used by DEQ to set temperature limits on point source dischargers and to evaluate the impact of management strategies on river temperatures to improve fish habitat. Some of these strategies included modifications of the dam at the Willamette River Falls south of Portland and channel reconfigurations. Once the models were set-up for each section of the Willamette basin, the model was calibrated to field data and management strategies were evaluated. These are the subjects of two other reports: Annear et al. (2004) and Berger et al. (2004). This report outlines the results of implementing model scenarios for each of the model sections or elements for specific time periods. The model scenario simulation periods used to investigate management scenarios required boundary condition data that extended past the model calibration periods. The model simulation period for year 2001 was from June 1 to October 31 and for year 2002 from April 1 to October 31. Title: Willamette River Basin Temperature TMDL Model: Model Scenarios Author: Annear, Robert Leslie, McKillip, Michael Lee, Khan, Sher Jamal, Berger, Chris, Wells, Scott A. Year: 2004 The State of Oregon Department of Environmental Quality (DEQ) is developing a TMDL for temperature in the Willamette River basin shown in Figure 1. The study area included the Willamette River and all major tributaries (except the Tualatin River where a TMDL process was already concluded). A large section of the Columbia River was also modeled to provide adequate boundary representation of tidal flows in the lower Willamette River. The Willamette River below the Oregon City Falls in the Portland metropolitan area has a typical diurnal tidal range of 1 m. The development of a dynamic model of temperature and hydrodynamics of the entire river basin incorporating shading were primary requirements of this modeling study. The model would be used by DEQ to set temperature limits on point source dischargers and to evaluate the impact of management strategies on river temperatures to improve fish habitat. Some of these strategies included modifications of the dam at the Willamette River Falls south of Portland and channel reconfigurations. Once the models were set-up for each section of the Willamette basin, the model was calibrated to field data and management strategies were evaluated. These are the subjects of two other reports: Annear et al. (2004) and Berger et al. (2004). This report outlines the results of implementing model scenarios for each of the model sections or elements for specific time periods. The model scenario simulation periods used to investigate management scenarios required boundary condition data that extended past the model calibration periods. The model simulation period for year 2001 was from June 1 to October 31 and for year 2002 from April 1 to October 31. Close

• 7. [Article] Willamette River Basin Temperature TMDL Model: Boundary Conditions and Model Setup

  The State of Oregon Department of Environmental Quality (DEQ) is developing a TMDL for temperature in the Willamette River basin shown in Figure 1. The study area included the Willamette River and all ...

  Citation × Citation Citation Abstract Copy Title: Willamette River Basin Temperature TMDL Model: Boundary Conditions and Model Setup Author: Annear, Robert Leslie, McKillip, Michael Lee, Khan, Sher Jamal, Berger, Chris, Wells, Scott A. Year: 2004 The State of Oregon Department of Environmental Quality (DEQ) is developing a TMDL for temperature in the Willamette River basin shown in Figure 1. The study area included the Willamette River and all major tributaries (except the Tualatin River where a TMDL process was already concluded). A large section of the Columbia River was also modeled to provide adequate boundary representation of tidal flows in the lower Willamette River. The Willamette River below the Oregon City Falls in the Portland metropolitan area has a typical diurnal tidal range of 1 m. The development of a dynamic model of temperature and hydrodynamics of the entire river basin incorporating shading were primary requirements of this modeling study. The model would be used by DEQ to set temperature limits on point source dischargers and to evaluate the impact of management strategies on river temperatures to improve fish habitat. Some of these strategies included modifications of the dam at the Willamette River Falls south of Portland and channel reconfigurations. Once the models were set-up for each section of the Willamette basin, the model was calibrated to field data and management strategies were evaluated. These are the subjects of two other reports: Annear et al. (2004b) and Berger et al. (2004). This report outlines the model development of each of these model sections or elements for both the calibration time periods and the management scenario time periods. The calibration period for each model section differs due to the availability of boundary condition data. The model simulation periods used to investigate management scenarios (Annear et al, 2004b) also required boundary condition data that extended past the calibration periods. Title: Willamette River Basin Temperature TMDL Model: Boundary Conditions and Model Setup Author: Annear, Robert Leslie, McKillip, Michael Lee, Khan, Sher Jamal, Berger, Chris, Wells, Scott A. Year: 2004 The State of Oregon Department of Environmental Quality (DEQ) is developing a TMDL for temperature in the Willamette River basin shown in Figure 1. The study area included the Willamette River and all major tributaries (except the Tualatin River where a TMDL process was already concluded). A large section of the Columbia River was also modeled to provide adequate boundary representation of tidal flows in the lower Willamette River. The Willamette River below the Oregon City Falls in the Portland metropolitan area has a typical diurnal tidal range of 1 m. The development of a dynamic model of temperature and hydrodynamics of the entire river basin incorporating shading were primary requirements of this modeling study. The model would be used by DEQ to set temperature limits on point source dischargers and to evaluate the impact of management strategies on river temperatures to improve fish habitat. Some of these strategies included modifications of the dam at the Willamette River Falls south of Portland and channel reconfigurations. Once the models were set-up for each section of the Willamette basin, the model was calibrated to field data and management strategies were evaluated. These are the subjects of two other reports: Annear et al. (2004b) and Berger et al. (2004). This report outlines the model development of each of these model sections or elements for both the calibration time periods and the management scenario time periods. The calibration period for each model section differs due to the availability of boundary condition data. The model simulation periods used to investigate management scenarios (Annear et al, 2004b) also required boundary condition data that extended past the calibration periods. Close

• 8. [Article] 3D Numerical Temperature Model Development and Calibration for Lakes and Reservoirs: A Case Study

  A 3D hydrodynamic and temperature numerical model was developed and calibrated for Lake Chaplain, Washington, USA. The governing equations are the continuity equation, free surface equation, momentum equation, ...

  Citation × Citation Citation Abstract Copy Title: 3D Numerical Temperature Model Development and Calibration for Lakes and Reservoirs: A Case Study Author: Al-Zubaidi, Hussein A. M., Wells, Scott A. Year: 2017 A 3D hydrodynamic and temperature numerical model was developed and calibrated for Lake Chaplain, Washington, USA. The governing equations are the continuity equation, free surface equation, momentum equation, and conservation equation of transport. The model employs the semi-implicit finite difference scheme to solve the governing equations and higher order schemes (QUICK and Quickest) for mass and heat transport in contrast to simpler but more diffusive first order UPWIND scheme. A unique feature of the 3D numerical solution of the model free surface equation is that the solution uses a tri-diagonal matrix form rather than a more common pentadiagonal matrix. The surface heat exchange and turbulence structure were based on the CE-QUAL-W2 model. Comparisons in water surface levels and temperature vertical profiles between model predictions and data were performed using different advective transport schemes. The model matched data with good error statistics. Title: 3D Numerical Temperature Model Development and Calibration for Lakes and Reservoirs: A Case Study Author: Al-Zubaidi, Hussein A. M., Wells, Scott A. Year: 2017 A 3D hydrodynamic and temperature numerical model was developed and calibrated for Lake Chaplain, Washington, USA. The governing equations are the continuity equation, free surface equation, momentum equation, and conservation equation of transport. The model employs the semi-implicit finite difference scheme to solve the governing equations and higher order schemes (QUICK and Quickest) for mass and heat transport in contrast to simpler but more diffusive first order UPWIND scheme. A unique feature of the 3D numerical solution of the model free surface equation is that the solution uses a tri-diagonal matrix form rather than a more common pentadiagonal matrix. The surface heat exchange and turbulence structure were based on the CE-QUAL-W2 model. Comparisons in water surface levels and temperature vertical profiles between model predictions and data were performed using different advective transport schemes. The model matched data with good error statistics. Close

• 9. [Article] A Comparison of Five Models for Estimating Clear-Sky Solar Radiation

  Many agencies in the USA are developing management approaches to address water quality concerns and threatened and endangered species habitat requirements in water bodies. Many of these water bodies are ...

  Citation × Citation Citation Abstract Copy Title: A Comparison of Five Models for Estimating Clear-Sky Solar Radiation Author: Annear, Robert Leslie, Wells, Scott A. Year: 2007 Many agencies in the USA are developing management approaches to address water quality concerns and threatened and endangered species habitat requirements in water bodies. Many of these water bodies are water quality limited for temperature. Factors influencing stream temperature include: streamside vegetation, topographic shading, inflows and outflows, stream width, stream depth, light extinction and solar radiation. One of the key driving factors in estimating a water body heat budget is calculating the amount of solar radiation incident on the water surface. Even though it is preferable to measure clear-sky solar radiation, many temperature models rely on theoretical estimates of clear-sky solar radiation. The literature on estimating short-wave solar radiation by calculating the position of the sun and attenuating the radiation through the atmosphere was reviewed. As a first step in relating water temperature to solar radiation, several empirical solar radiation models were calibrated to data at seventeen sites around the United States for clear-sky days. Sensitivity analyses were conducted and differences between the models were examined. Results indicated that the more complex models for calculating solar radiation resulted in better estimates of clear-sky solar radiation once they were calibrated to data. When no data were available, models with one or no calibration parameters did reasonably well at estimating clear-sky solar radiation. Title: A Comparison of Five Models for Estimating Clear-Sky Solar Radiation Author: Annear, Robert Leslie, Wells, Scott A. Year: 2007 Many agencies in the USA are developing management approaches to address water quality concerns and threatened and endangered species habitat requirements in water bodies. Many of these water bodies are water quality limited for temperature. Factors influencing stream temperature include: streamside vegetation, topographic shading, inflows and outflows, stream width, stream depth, light extinction and solar radiation. One of the key driving factors in estimating a water body heat budget is calculating the amount of solar radiation incident on the water surface. Even though it is preferable to measure clear-sky solar radiation, many temperature models rely on theoretical estimates of clear-sky solar radiation. The literature on estimating short-wave solar radiation by calculating the position of the sun and attenuating the radiation through the atmosphere was reviewed. As a first step in relating water temperature to solar radiation, several empirical solar radiation models were calibrated to data at seventeen sites around the United States for clear-sky days. Sensitivity analyses were conducted and differences between the models were examined. Results indicated that the more complex models for calculating solar radiation resulted in better estimates of clear-sky solar radiation once they were calibrated to data. When no data were available, models with one or no calibration parameters did reasonably well at estimating clear-sky solar radiation. Close

• 10. [Article] Modeling Density Currents in a Typical Tributary of the Three Gorges Reservoir, China

  The initial filling of the Three Gorges Reservoir (TGR), China, has caused serious phytoplankton blooms in its tributary bays. A two-dimensional, laterally averaged, hydrodynamic and water quality CE-QUAL-W2 ...

  Citation × Citation Citation Abstract Copy Title: Modeling Density Currents in a Typical Tributary of the Three Gorges Reservoir, China Author: Ma, Jun, Liu, Defu, Wells, Scott A., Tang, Hongwu, Ji, Daobin, Yang, Zhengjian Year: 2015 The initial filling of the Three Gorges Reservoir (TGR), China, has caused serious phytoplankton blooms in its tributary bays. A two-dimensional, laterally averaged, hydrodynamic and water quality CE-QUAL-W2 model was used to simulate the hydrodynamics and water temperature of a typical tributary (Xiangxi Bay XXB) of the TGR to study the relationship between phytoplankton and density currents. The CE-QUAL-W2 model was calibrated to data collected in XXB (depth profiles of velocity and water temperature at three locations) from January 2008 through December 2008. The model performed well in simulating (1) flow velocity profiles, (2) unusual water temperature profiles, (3) the plunge point location of the intrusion layer, (4) propagation speed, and (5) the travel distance of the density currents. The model was then used to examine potential factors that affect the density currents, such as water level fluctuations in the mainstem of the TGR, water temperature differences between the mainstem and XXB, and inflow rates to XXB. Therefore, a better understanding of the hydrodynamics of tributaries in the TGR can be used to understand the aquatic ecosystem dynamics of these tributaries. Title: Modeling Density Currents in a Typical Tributary of the Three Gorges Reservoir, China Author: Ma, Jun, Liu, Defu, Wells, Scott A., Tang, Hongwu, Ji, Daobin, Yang, Zhengjian Year: 2015 The initial filling of the Three Gorges Reservoir (TGR), China, has caused serious phytoplankton blooms in its tributary bays. A two-dimensional, laterally averaged, hydrodynamic and water quality CE-QUAL-W2 model was used to simulate the hydrodynamics and water temperature of a typical tributary (Xiangxi Bay XXB) of the TGR to study the relationship between phytoplankton and density currents. The CE-QUAL-W2 model was calibrated to data collected in XXB (depth profiles of velocity and water temperature at three locations) from January 2008 through December 2008. The model performed well in simulating (1) flow velocity profiles, (2) unusual water temperature profiles, (3) the plunge point location of the intrusion layer, (4) propagation speed, and (5) the travel distance of the density currents. The model was then used to examine potential factors that affect the density currents, such as water level fluctuations in the mainstem of the TGR, water temperature differences between the mainstem and XXB, and inflow rates to XXB. Therefore, a better understanding of the hydrodynamics of tributaries in the TGR can be used to understand the aquatic ecosystem dynamics of these tributaries. Close