Greg Pelletier - Profile on Academia.edu (original) (raw)
Papers by Greg Pelletier
Wind River Water Quality Improvement Project
Stochastic Water Quality Modeling of an Impaired River Impacted by Climate Change
Journal of Environmental Engineering, 2015
Since its introduction in the 1970s as a valid and useful approach to simulating free flows, vari... more Since its introduction in the 1970s as a valid and useful approach to simulating free flows, various mathematical implementations of Lagrangian plume models were developed and verified, both for atmospheric and aquatic discharges. Valid for both jets and plumes, some of these models, including the Visual Plumes UM3 and JETLAG models, are widely used to predict or assess the dispersion performance of outfall structures, or diffusers. In addition to dilution, they also predict trajectories, rise, plume merging, and other properties and behaviors. The success of the Lagrangian plume models was attributed, at least partially, to the projected area entrainment (PAE) hypothesis. The PAE hypothesis states that forced entrainment into the Lagrangian plume element (a control volume) is equal to the ambient flow through the plume element projected area in unit time. Forced entrainment is the dominant entrainment mechanism in moderate to high current and augments the Taylor (or aspiration) ent...
Model-Derived Hydrodynamics of Inlets in South Puget Sound
Estuarine and Coastal Modeling (2009), 2010
ABSTRACT A recent model application has been developed by the Washington State Dept. of Ecology t... more ABSTRACT A recent model application has been developed by the Washington State Dept. of Ecology that simulates water circulation in South Puget Sound (SPS) using the Generalized Environmental Modeling System for Surface waters (GEMSS) with an open northern boundary near Edmonds, WA. Post-calibration root mean square errors (RMSEs) are <5% of Ehe tidal range in all but Oakland Bay where the error was 10% of the tidal range. The model simulates salinity with a RMSE of 0.6 psu near the surface and 0.5 psu near the seafloor compared with field observations at 22 key stations.
A Guide to the Regulatory, Technical, and Theoretical Basis for Required Studies, 2007
Development of a Minimalistic Data Collection Strategy for QUAL2Kw
Journal of Water Resources Planning and Management, 2014
QUAL2K: A Modeling Framework for Simulating River and Stream Water Quality
Journal of Environmental Engineering, 2009
Environmental Science & Technology, 2010
To date the impact of thermal emissions has not been addressed in life cycle assessment despite t... more To date the impact of thermal emissions has not been addressed in life cycle assessment despite the narrow thermal tolerance of most aquatic species. A method to derive characterization factors for the impact of cooling water discharges on aquatic ecosystems was developed which uses space and time explicit integration of fate and effects of water temperature changes. The fate factor is calculated with a 1-dimensional steady-state model and reflects the residence time of heat emissions in the river. The effect factor specifies the loss of species diversity per unit of temperature increase and is based on a species sensitivity distribution of temperature tolerance intervals for various aquatic species. As an example, time explicit characterization factors were calculated for the cooling water discharge of a nuclear power plant in Switzerland, quantifying the impact on aquatic ecosystems of the rivers Aare and Rhine. The relative importance of the impact of these cooling water discharges was compared with other impacts in life cycle assessment. We found that thermal emissions are relevant for aquatic ecosystems compared to other stressors, such as chemicals and nutrients. For the case of nuclear electricity investigated, thermal emissions contribute between 3% and over 90% to Ecosystem Quality damage.
Environmental Modelling & Software, 2006
QUAL2Kw is a framework for the simulation of water quality in streams and rivers. Dynamic diel he... more QUAL2Kw is a framework for the simulation of water quality in streams and rivers. Dynamic diel heat budget and water quality kinetics are calculated for one-dimensional steady-flow systems. The framework includes a genetic algorithm to facilitate the calibration of the model in application to particular waterbodies. The genetic algorithm is used to find the combination of kinetic rate parameters and constants that results in a best fit for a model application compared with observed data. The user has the flexibility to select any combination of parameters for the optimization and specify any appropriate function for goodness-of-fit.
Ecological Modelling, 2007
Bagmati River a b s t r a c t
Water quality modeling for urban reach of Yamuna river, India (1999–2009), using QUAL2Kw
Applied Water Science, 2015
Wind River Water Quality Improvement Project
Stochastic Water Quality Modeling of an Impaired River Impacted by Climate Change
Journal of Environmental Engineering, 2015
Since its introduction in the 1970s as a valid and useful approach to simulating free flows, vari... more Since its introduction in the 1970s as a valid and useful approach to simulating free flows, various mathematical implementations of Lagrangian plume models were developed and verified, both for atmospheric and aquatic discharges. Valid for both jets and plumes, some of these models, including the Visual Plumes UM3 and JETLAG models, are widely used to predict or assess the dispersion performance of outfall structures, or diffusers. In addition to dilution, they also predict trajectories, rise, plume merging, and other properties and behaviors. The success of the Lagrangian plume models was attributed, at least partially, to the projected area entrainment (PAE) hypothesis. The PAE hypothesis states that forced entrainment into the Lagrangian plume element (a control volume) is equal to the ambient flow through the plume element projected area in unit time. Forced entrainment is the dominant entrainment mechanism in moderate to high current and augments the Taylor (or aspiration) ent...
Model-Derived Hydrodynamics of Inlets in South Puget Sound
Estuarine and Coastal Modeling (2009), 2010
ABSTRACT A recent model application has been developed by the Washington State Dept. of Ecology t... more ABSTRACT A recent model application has been developed by the Washington State Dept. of Ecology that simulates water circulation in South Puget Sound (SPS) using the Generalized Environmental Modeling System for Surface waters (GEMSS) with an open northern boundary near Edmonds, WA. Post-calibration root mean square errors (RMSEs) are <5% of Ehe tidal range in all but Oakland Bay where the error was 10% of the tidal range. The model simulates salinity with a RMSE of 0.6 psu near the surface and 0.5 psu near the seafloor compared with field observations at 22 key stations.
A Guide to the Regulatory, Technical, and Theoretical Basis for Required Studies, 2007
Development of a Minimalistic Data Collection Strategy for QUAL2Kw
Journal of Water Resources Planning and Management, 2014
QUAL2K: A Modeling Framework for Simulating River and Stream Water Quality
Journal of Environmental Engineering, 2009
Environmental Science & Technology, 2010
To date the impact of thermal emissions has not been addressed in life cycle assessment despite t... more To date the impact of thermal emissions has not been addressed in life cycle assessment despite the narrow thermal tolerance of most aquatic species. A method to derive characterization factors for the impact of cooling water discharges on aquatic ecosystems was developed which uses space and time explicit integration of fate and effects of water temperature changes. The fate factor is calculated with a 1-dimensional steady-state model and reflects the residence time of heat emissions in the river. The effect factor specifies the loss of species diversity per unit of temperature increase and is based on a species sensitivity distribution of temperature tolerance intervals for various aquatic species. As an example, time explicit characterization factors were calculated for the cooling water discharge of a nuclear power plant in Switzerland, quantifying the impact on aquatic ecosystems of the rivers Aare and Rhine. The relative importance of the impact of these cooling water discharges was compared with other impacts in life cycle assessment. We found that thermal emissions are relevant for aquatic ecosystems compared to other stressors, such as chemicals and nutrients. For the case of nuclear electricity investigated, thermal emissions contribute between 3% and over 90% to Ecosystem Quality damage.
Environmental Modelling & Software, 2006
QUAL2Kw is a framework for the simulation of water quality in streams and rivers. Dynamic diel he... more QUAL2Kw is a framework for the simulation of water quality in streams and rivers. Dynamic diel heat budget and water quality kinetics are calculated for one-dimensional steady-flow systems. The framework includes a genetic algorithm to facilitate the calibration of the model in application to particular waterbodies. The genetic algorithm is used to find the combination of kinetic rate parameters and constants that results in a best fit for a model application compared with observed data. The user has the flexibility to select any combination of parameters for the optimization and specify any appropriate function for goodness-of-fit.
Ecological Modelling, 2007
Bagmati River a b s t r a c t
Water quality modeling for urban reach of Yamuna river, India (1999–2009), using QUAL2Kw
Applied Water Science, 2015