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Full-Text Articles in Engineering

Warming Of The Willamette River, 1850–Present: The Effects Of Climate Change And Direct Human Interventions, Stefan Talke, David Jay, Heida Diefenderfer Sep 2022

Warming Of The Willamette River, 1850–Present: The Effects Of Climate Change And Direct Human Interventions, Stefan Talke, David Jay, Heida Diefenderfer

Civil and Environmental Engineering Faculty Publications and Presentations

Using archival research methods, we found and combined data from multiple sources to produce a unique, 140 year record of daily water temperature (Tw) in the lower Willamette River, Oregon (1881–1890, 1941–present). Additional daily weather and river flow records from the 1850s onwards are used to develop and validate a statistical regression model of Tw for 1850–2020. The model simulates the time-lagged response of Tw to air temperature and river flow, and is calibrated for three distinct time periods: the late 19th, mid 20th, and early 21st centuries. Results show that Tw has trended upwards at ~1.1 °C …


Storm Tide Amplification And Habitat Changes Due To Urbanization Of A Lagoonal Estuary, Philip Orton, Eric W. Sanderson, Stefan Talke, Mario Giampieri, Kytt Macmanus Jan 2020

Storm Tide Amplification And Habitat Changes Due To Urbanization Of A Lagoonal Estuary, Philip Orton, Eric W. Sanderson, Stefan Talke, Mario Giampieri, Kytt Macmanus

Civil and Environmental Engineering Faculty Publications and Presentations

In recent centuries, human activities have greatly modified the geomorphology of coastal regions. However, studies of historical and possible future changes in coastal flood extremes typically ignore the influence of geomorphic change. Here, we quantify the influence of 20th-century man-made changes to Jamaica Bay, New York City, on present-day storm tides. We develop and validate a hydrodynamic model for the 1870s based on detailed maps of bathymetry, seabed characteristics, topography, and tide observations for use alongside a present-day model. Predominantly through dredging, landfill, and inlet stabilization, the average water depth of the bay increased from 1.7 to 4.5 m, tidal …


Decision Support System For The Design And Planning Of Low-Impact Development Practices: The Case Of Seoul, Jae-Yeol Song, Eun-Sung Chung, Soo Hyun Kim Feb 2018

Decision Support System For The Design And Planning Of Low-Impact Development Practices: The Case Of Seoul, Jae-Yeol Song, Eun-Sung Chung, Soo Hyun Kim

Civil and Environmental Engineering Faculty Publications and Presentations

This study presented the conceptual framework of the water-management analysis module (WMAM) to derive effective physical specifications for the design and planning of low-impact development (LID) practices using the storm-water management model (SWMM). This decision-support system can be used for six LID types and has the following key capabilities: determining relevant LID design parameters within the SWMM that critically influence the hydrological cycle components using a simple sensitivity analysis and determining the best hydrological values for LID planning specification. This study analyzed a highly urbanized university campus as a case study to determine the design and planning specifications for an …


Apprehensive Drought Characteristics Over Iraq: Results Of A Multidecadal Spatiotemporal Assessment, Maysoun Ayad Hameed, Ali Ahmadalipour, Hamid Moradkhani Feb 2018

Apprehensive Drought Characteristics Over Iraq: Results Of A Multidecadal Spatiotemporal Assessment, Maysoun Ayad Hameed, Ali Ahmadalipour, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

Drought is an extreme climate phenomenon that happens slowly and periodically threatens the environmental and socio-economic sectors. Iraq is one of the countries in the Middle East that has been dealing with serious drought-related issues in the 21st century. Here, we investigate meteorological drought across Iraq from 1948 to 2009 at 0.25° spatial resolution. The Standardized Precipitation Evapotranspiration Index (SPEI) has been utilized as a multi-scalar drought index accounting for the effects of temperature variability on drought. Four of the main characteristics of drought including extent, intensity, frequency and duration are studied and the associated spatiotemporal patterns are investigated for …


The Effects Of Global Change Upon United States Air Quality, Rodrigo Gonzalez-Abraham, Serena H. Chung, Jeremy C. Avise, Brian Lamb, Eric P. Salathé Jr., Christopher G. Nolte, Dan Loughlin, Alex Guenther, Christine Wiedinmyer, Tiffany Duhl, Yang Zhang, David G. Streets Jan 2015

The Effects Of Global Change Upon United States Air Quality, Rodrigo Gonzalez-Abraham, Serena H. Chung, Jeremy C. Avise, Brian Lamb, Eric P. Salathé Jr., Christopher G. Nolte, Dan Loughlin, Alex Guenther, Christine Wiedinmyer, Tiffany Duhl, Yang Zhang, David G. Streets

Civil and Environmental Engineering Faculty Publications and Presentations

To understand more fully the effects of global changes on ambient concentrations of ozone and particulate matter with aerodynamic diameter smaller than 2.5 μm (PM2.5) in the United States (US), we conducted a comprehensive modeling effort to evaluate explicitly the effects of changes in climate, biogenic emissions, land use and global/regional anthropogenic emissions on ozone and PM2.5 concentrations and composition. Results from the ECHAM5 global climate model driven with the A1B emission scenario from the Intergovernmental Panel on Climate Change (IPCC) were downscaled using the Weather Research and Forecasting (WRF) model to provide regional meteorological fields. We …


Secondary Organic Aerosol Formation And Organic Nitrate Yield From No3 Oxidation Of Biogenic Hydrocarbons, Juliane L. Fry, Danielle C. Draper, Kelley C. Barsanti, James N. Smith, John Ortega, Paul M. Winkler, Michael J. Lawler, Steven S. Brown, Peter M. Edwards, Ronald C. Cohen, Lance Lee Sep 2014

Secondary Organic Aerosol Formation And Organic Nitrate Yield From No3 Oxidation Of Biogenic Hydrocarbons, Juliane L. Fry, Danielle C. Draper, Kelley C. Barsanti, James N. Smith, John Ortega, Paul M. Winkler, Michael J. Lawler, Steven S. Brown, Peter M. Edwards, Ronald C. Cohen, Lance Lee

Civil and Environmental Engineering Faculty Publications and Presentations

The secondary organic aerosol (SOA) mass yields from NO3 oxidation of a series of biogenic volatile organic compounds (BVOCs), consisting of five monoterpenes and one sesquiterpene (α-pinene, β-pinene, Δ-3-carene, limonene, sabinene, and β-caryophyllene), were investigated in a series of continuous flow experiments in a 10 m3 indoor Teflon chamber. By making in situ measurements of the nitrate radical and employing a kinetics box model, we generate time-dependent yield curves as a function of reacted BVOC. SOA yields varied dramatically among the different BVOCs, from zero for α-pinene to 38−65% for Δ-3-carene and 86% for β-caryophyllene at mass loading of 10 …


Bicycle Facilities And The Uptake Of Air Pollution By Active Travelers, Alexander Y. Bigazzi, Miguel A. Figliozzi, James F. Pankow, Wentai Luo, Lorne M. Isabelle Mar 2014

Bicycle Facilities And The Uptake Of Air Pollution By Active Travelers, Alexander Y. Bigazzi, Miguel A. Figliozzi, James F. Pankow, Wentai Luo, Lorne M. Isabelle

Civil and Environmental Engineering Faculty Publications and Presentations

Outlines the research of urban bicyclists' facilities and the uptake of air pollution by active travelers in urban Portland, OR. Outlines the research goals, beginning data collection methods, intake/uptake, modeling results, conclusions and the next steps for future work with the collected data set of direct uptake measurements.


Analyzing Experimental Data And Model Parameters: Implications For Predictions Of Soa Using Chemical Transport Models, Kelley Barsanti, Annmarie G. Carlton, Serena H. Chung Jan 2013

Analyzing Experimental Data And Model Parameters: Implications For Predictions Of Soa Using Chemical Transport Models, Kelley Barsanti, Annmarie G. Carlton, Serena H. Chung

Civil and Environmental Engineering Faculty Publications and Presentations

Despite critical importance for air quality and climate predictions, accurate representation of secondary organic aerosol (SOA) formation remains elusive. An essential addition to the ongoing discussion of improving model predictions is an acknowledgement of the linkages between experimental conditions, parameter optimization and model output, as well as the linkage between empirically-derived partitioning parameters and the physicochemical properties of SOA they represent in models. In this work, a "best available" set of SOA modeling parameters is selected by comparing predicted SOA yields and mass concentrations with observed yields and mass concentrations from a comprehensive list of published smog chamber studies. Evaluated …


Lake Whatcom Model Calibration With Variable Stoichiometry In Sediments - Revised, Chris Berger, Scott A. Wells Feb 2007

Lake Whatcom Model Calibration With Variable Stoichiometry In Sediments - Revised, Chris Berger, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

This memorandum discusses model calibration and enhancements made to the Lake Whatcom water quality model. Model development and initial calibration were documented in the report “Lake Whatcom Water Quality Model” (Berger and Wells, 2005). The Lake Whatcom water quality model has been converted from CE-QUAL-W2 version 3.2 to version 3.5 (Cole and Wells, 2006).


Lake Whatcom Water Quality Model, Chris Berger Jul 2005

Lake Whatcom Water Quality Model, Chris Berger

Civil and Environmental Engineering Faculty Publications and Presentations

A water quality model of Lake Whatcom, Washington was developed as part of a Total Maximum Daily Load Study for the Washington Department of Ecology. Lake Whatcom is a large natural lake which is listed on the 1998 Washington State 303(d) list of waterbodies which do not meet the criterion for dissolved oxygen. Located next to the city of Bellingham, it is approximately 10 miles long and has a surface area of approximately 5000 acres and a maximum depth of over 100 meters. Eutrophication processes in the lake have been accelerated in recent years perhaps by the availability of nutrients …