Hydraulic Engineering Commons^™

The Effect Of Multi-Model Averaging Of Climate Model Outputs On The Seasonality Of Rainfall Over The Columbia River Basin, Mehmet Demirel, Arun Rana, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

The rainfall seasonality index is the measure of precipitation distribution throughout the seasonal cycle. The aim of this study is to compare the effect of different multi-model averaging methods on the rainfall seasonality index at each 1/16 latitude-longitude cells covering the Columbia River Basin. In accordance with the same, ten different climate model outputs are selected from 45 available climate models from CMIP5 dataset. The reanalysis precipitation data is used to estimate the errors in rainfall seasonality for the climate model outputs. The inverse variance method and statistical multi criteria analysis (SMCA) method were used to estimate the weights for …

Modeling Historic Columbia River Flood Impacts, Lumas Helaire, Andrew Mahedy, Stefan A. Talke, David A. Jay

Civil and Environmental Engineering Faculty Publications and Presentations

The Lower Columbia River Estuary (LCRE) has undergone extensive modifications since the 19^th century. Construction of dams, installation of jetties and dikes, dredging of the navigation channel and filling in of tidal wetlands have all contributed significantly to alterations in tidal dynamics and the flow regime, with consequences for habitat inundation and salinity intrusion. In this talk we discuss the development and implementation of a 19^th century flow model for the LCRE, using a digital elevation model based on historic bathymetry. The model has been calibrated with recently rediscovered and digitized tide data from the 19^th century. …

Toward Reduction Of Model Uncertainty: Integration Of Bayesian Model Averaging And Data Assimilation, Mark A. Parrish, Hamid Moradkhani, Caleb Matthew Dechant

Civil and Environmental Engineering Faculty Publications and Presentations

Multimodeling in hydrologic forecasting has proved to improve upon the systematic bias and general limitations of a single model. This is typically done by establishing a new model as a linear combination or a weighted average of several models with weights on the basis of individual model performance in previous time steps. The most commonly used multimodeling method, Bayesian model averaging (BMA), assumes a fixed probability distribution around individual models' forecast in establishing the prior and uses a calibration period to determine static weights for each individual model. More recent work has focused on a sequential Bayesian model selection technique …

Coupling The Hydrodynamic And Water Quality Model Ce-Qual-W2 With A Multi-Trophic Fish Bio-Energetics Model For Lake Roosevelt, Washington, Michael Lee Mckillip

Dissertations and Theses

Grand Coulee Dam created Franklin D. Roosevelt Lake as part of the Columbia Basin Project. Located in northeastern Washington State, the Project provides economically important hydropower (19 billion kilowatt hours per year), irrigation (225,000 ha), flood control, and sport fishing ($5 to 20 million annually). A good system understanding aids in balancing these beneficial uses for the 230 km long reservoir. The reservoir's atypical 45-day mean residence time is much shorter than a typical lake, and much longer than for a riverine dam. The spring freshet requires drawdowns of 15 to 20 m for flood control—the driving characteristic of reservoir …

Waldo Lake Research In 2004, Mark D. Sytsma, John Rueter, Richard Petersen, Roy Koch, Scott A. Wells, Michelle Wood, Yangdong Pan, Robert Leslie Annear, Aaron Hook, Laura Johnson, Rich Miller, Amanda Murphy, Terry Stoltz

Center for Lakes and Reservoirs Publications and Presentations

The Willamette National Forest has worked with Portland State University, Center for Lakes and Reservoirs (PSU) and the University of Oregon (UO) to investigate ecosystem changes, provide guidance on long-term monitoring methods, assess monitoring data, develop predictive water quality models, and conduct research that will lead to better protection and understanding of the Waldo Lake ecosystem. This report summarizes the second year of collaborative PSU-UO research at Waldo Lake. Research has focused on understanding physical, chemical and biological characteristics of Waldo Lake across a range of spatial and temporal scales. Research tasks that continued from 2003 into 2004 included temperature …

The Applicability Of Microcomputers To Local Water Management, Roderick Lee Allen

Dissertations and Theses

Historically, hydrologic models have been available only on mainframe computers and have therefore not been used by local water managers to support daily decisions. The development of the microcomputer presents an opportunity for that to change.

Mathematical models of soil moisture and river routing are selected, developed and tested for use on a microcomputer as an aid to local water management. The models are then integrated with an appropriate data base in a computer program written for a microcomputer. The result is a Decision Support System for local water managers.

In order to evaluate the feasibility of using the Decision …