Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Hydrology

Series

Portland State University

Keyword
Publication Year
Publication

Articles 1 - 30 of 83

Full-Text Articles in Physical Sciences and Mathematics

Water Quality Land Cover Change And Water Quality In Wetlands At The City Of Gresham, Or, Evelyn Barajas, Michael Gonzalez Aug 2023

Water Quality Land Cover Change And Water Quality In Wetlands At The City Of Gresham, Or, Evelyn Barajas, Michael Gonzalez

altREU Projects

The City of Gresham, Oregon has implemented constructed wetlands around the area as an attempt to collect, filter, and purify water from different sources such as rain, agricultural waste, and domestic waste. We focused our research on three different facilities: Columbia Slough Water Quality Facility (CSWQF), Fairview Creek Water Quality Facility, and Brookside Water Quality Facility. For each of these, we conducted tests and looked at the concentration levels for nitrogen and phosphorus nutrients such as NH3-N (ammonium), NO3-N (nitrate), TKN (total Kjeldahl nitrogen), O-PO4 (phosphate), and Total P (total phosphorus), as well as heavy metals like Total Cu (total …


Catastrophic Beach Sand Losses Due To Erosion From Predicted Future Sea Level Rise (0.5–1.0 M), Based On Increasing Submarine Accommodation Spaces In The High-Wave-Energy Coast Of The Pacific Northwest, Washington, Oregon, And Northern California, Usa, Curt D. Peterson, Don Joseph Pettit, Kara E. P. Kingen, Sandy Vanderburgh, Chuck Rosenfeld Sep 2021

Catastrophic Beach Sand Losses Due To Erosion From Predicted Future Sea Level Rise (0.5–1.0 M), Based On Increasing Submarine Accommodation Spaces In The High-Wave-Energy Coast Of The Pacific Northwest, Washington, Oregon, And Northern California, Usa, Curt D. Peterson, Don Joseph Pettit, Kara E. P. Kingen, Sandy Vanderburgh, Chuck Rosenfeld

Geology Faculty Publications and Presentations

The U.S. Pacific Northwest (PNW) coastline (1000 km) has been analyzed for conditions that could impact beach erosion from potential near-future (100 year) sea level rise (SLR). Heavy mineral analysis of river, beach, and shelf samples (n = 105) establish the sources of the beach deposits. River bedload discharge and intervening estuarine sinks for river sand supplies (n = 31) were normalized to the one century time interval. Twenty-six subcell beaches (657 km in combined length) were surveyed (153 profiles) for beach sand widths (20–412 m) and sand cross-sectional areas (20–1810 m2 ) above wave-cut platforms and/or 0 m tidal …


Spatial Analysis Of Landscape Characteristics, Anthropogenic Factors, And Seasonality Effects On Water Quality In Portland, Oregon, Katherine Gelsey, Daniel Ramirez Aug 2021

Spatial Analysis Of Landscape Characteristics, Anthropogenic Factors, And Seasonality Effects On Water Quality In Portland, Oregon, Katherine Gelsey, Daniel Ramirez

REU Final Reports

Urban areas often struggle with deteriorated water quality as a result of complex interactions between landscape factors such as land cover, use, and management as well as climatic variables such as weather, precipitation, and atmospheric conditions. Green stormwater infrastructure (GSI) has been introduced as a strategy to reintroduce pre-development hydrological conditions in cities, but questions remain as to how GSI interacts with other landscape factors to affect water quality. We conducted a statistical analysis of six relevant water quality indicators in 131 water quality stations in four watersheds around Portland, Oregon using data from 2015 to 2021. Indiscriminate of station …


Altimetry For The Future: Building On 25 Years Of Progress, Saleh Abdalla, Abdolnabi Kolahchi, Micheal Ablain, Susheel Adusumilli, Suchandra Aich Bhowmick, Eva Alou-Font, Laiba Amarouche, Ole Baltazar Andersen, Edward Zaron, Multiple Additional Authors Mar 2021

Altimetry For The Future: Building On 25 Years Of Progress, Saleh Abdalla, Abdolnabi Kolahchi, Micheal Ablain, Susheel Adusumilli, Suchandra Aich Bhowmick, Eva Alou-Font, Laiba Amarouche, Ole Baltazar Andersen, Edward Zaron, Multiple Additional Authors

Civil and Environmental Engineering Faculty Publications and Presentations

In 2018 we celebrated 25 years of development of radar altimetry, and the progress achieved by this methodology in the fields of global and coastal oceanography, hydrology, geodesy and cryospheric sciences. Many symbolic major events have celebrated these developments, e.g., in Venice, Italy, the 15th (2006) and 20th (2012) years of progress and more recently, in 2018, in Ponta Delgada, Portugal, 25 Years of Progress in Radar Altimetry. On this latter occasion it was decided to collect contributions of scientists, engineers and managers involved in the worldwide altimetry community to depict the state of altimetry and propose recommendations for the …


The Role Of Warm, Dry Summers And Variation In Snowpack On Phytoplankton Dynamics In Mountain Lakes, Isabella A. Olesky, Whitney S. Beck, Roderick W. Lammers, Cara E. Steger, Codie Wilson, Kyle R. Christianson, Kim Vincent, Gunnar Forrest Johnson, Pieter T.J. Johnson, Jill S. Baron Jan 2020

The Role Of Warm, Dry Summers And Variation In Snowpack On Phytoplankton Dynamics In Mountain Lakes, Isabella A. Olesky, Whitney S. Beck, Roderick W. Lammers, Cara E. Steger, Codie Wilson, Kyle R. Christianson, Kim Vincent, Gunnar Forrest Johnson, Pieter T.J. Johnson, Jill S. Baron

Geology Faculty Publications and Presentations

Climate change is altering biogeochemical, metabolic, and ecological functions in lakes across the globe. Historically, mountain lakes in temperate regions have been unproductive because of brief ice-free seasons, a snowmelt-driven hydrograph, cold temperatures, and steep topography with low vegetation and soil cover. We tested the relative importance of winter and summer weather, watershed characteristics, and water chemistry as drivers of phytoplankton dynamics. Using boosted regression tree models for 28 mountain lakes in Colorado, we examined regional, intraseasonal, and interannual drivers of variability in chlorophyll a as a proxy for lake phytoplankton. Phytoplankton biomass was inversely related to the maximum snow …


Remote Sensing Of Water Use Efficiency And Terrestrial Drought Recovery Across The Contiguous United States, Behzad Ahmadi, Ali Ahmadalipour, Glenn Tootle Mar 2019

Remote Sensing Of Water Use Efficiency And Terrestrial Drought Recovery Across The Contiguous United States, Behzad Ahmadi, Ali Ahmadalipour, Glenn Tootle

Civil and Environmental Engineering Faculty Publications and Presentations

Ecosystem water-use efficiency (WUE) is defined as the ratio of carbon gain (i.e., gross primary productivity; GPP) to water consumption (i.e., evapotranspiration; ET). WUE is markedly influential on carbon and water cycles, both of which are fundamental for ecosystem state, climate and the environment. Drought can affect WUE, subsequently disturbing the composition and functionality of terrestrial ecosystems. In this study, the impacts of drought on WUE and its components (i.e., GPP and ET) are assessed across the Contiguous US (CONUS) at fine spatial and temporal resolutions. Soil moisture simulations from land surface modeling are utilized to detect and characterize agricultural …


Improved Drought Resilience Through Continuous Water Service Monitoring And Specialized Institutions—A Longitudinal Analysis Of Water Service Delivery Across Motorized Boreholes In Northern Kenya, Nick Turman-Bryant, Corey L. Nagel, Lauren Stover, Christian Muragijimana, Evan A. Thomas Jan 2019

Improved Drought Resilience Through Continuous Water Service Monitoring And Specialized Institutions—A Longitudinal Analysis Of Water Service Delivery Across Motorized Boreholes In Northern Kenya, Nick Turman-Bryant, Corey L. Nagel, Lauren Stover, Christian Muragijimana, Evan A. Thomas

Systems Science Faculty Publications and Presentations

Increasing frequency and severity of drought is driving increased use of groundwater resources in arid regions of Northern Kenya, where approximately 2.5 million people depend on groundwater for personal use, livestock, and limited irrigation. As part of a broader effort to provide more sustainable water, sanitation, and hygiene services in the region, we have collected data related to site functionality and use for approximately 120 motorized boreholes across five counties. Using a multilevel model to account for geospatial and temporal clustering, we found that borehole sites, which counties had identified as strategic assets during drought, ran on average about 1.31 …


Mechanics And Historical Evolution Of Sea Level Blowouts In New York Harbor, Praneeth Gurumurthy, Philip Orton, Stefan A. Talke, Nickitas Georgas, James F. Booth Jan 2019

Mechanics And Historical Evolution Of Sea Level Blowouts In New York Harbor, Praneeth Gurumurthy, Philip Orton, Stefan A. Talke, Nickitas Georgas, James F. Booth

Civil and Environmental Engineering Faculty Publications and Presentations

Wind-induced sea level blowouts, measured as negative storm surge or extreme low water (ELW), produce public safety hazards and impose economic costs (e.g., to shipping). In this paper, we use a regional hydrodynamic numerical model to test the effect of historical environmental change and the time scale, direction, and magnitude of wind forcing on negative and positive surge events in the New York Harbor (NYH). Environmental sensitivity experiments show that dredging of shipping channels is an important factor affecting blowouts while changing ice cover and removal of other roughness elements are unimportant in NYH. Continuously measured water level records since …


Floodplains Provide Important Amphibian Habitat Despite Multiple Ecological Threats, Meredith Holgerson, Adam Duarte, Marc P. Hayes, Michael J. Adams, Julie A. Tyson, Keith A. Douville, Angela L. Strecker Jan 2019

Floodplains Provide Important Amphibian Habitat Despite Multiple Ecological Threats, Meredith Holgerson, Adam Duarte, Marc P. Hayes, Michael J. Adams, Julie A. Tyson, Keith A. Douville, Angela L. Strecker

Environmental Science and Management Faculty Publications and Presentations

Floodplain ponds and wetlands are productive and biodiverse ecosystems, yet they face multiple threats including altered hydrology, land use change, and non-native species. Protecting and restoring important floodplain ecosystems requires understanding how organisms use these habitats and respond to altered environmental conditions. We developed Bayesian models to evaluate occupancy of six amphibian species across 103 off-channel aquatic habitats in the Chehalis River floodplain, Washington State, USA. The basin has been altered by changes in land use, reduced river–wetland connections, and the establishment of non-native American bullfrogs (Rana catesbeiana = Lithobates catesbeianus) and centrarchid fishes, all of which we hypothesized could …


Effects Of Water Level Fluctuation On Thermal Stratification In A Typical Tributary Bay Of Three Gorges Reservoir, China, Juxiang Jin, Scott Wells, Defu Liu, Guolu Yang, Senlin Zhu, Jun Ma, Zhengjian Yang Jan 2019

Effects Of Water Level Fluctuation On Thermal Stratification In A Typical Tributary Bay Of Three Gorges Reservoir, China, Juxiang Jin, Scott Wells, Defu Liu, Guolu Yang, Senlin Zhu, Jun Ma, Zhengjian Yang

Civil and Environmental Engineering Faculty Publications and Presentations

Xiangxi River is a typical tributary of Three Gorges Reservoir (TGR) in China. Based on field observations in 2010, thermal stratification was significant in most months of the year. Through field data analysis and numerical simulations, the seasonal and spatial variation of thermal stratification as related to the impact of the operation of TGR were investigated. Thermal stratification was most pronounced from April to September in the Xiangxi River tributary. Air temperature (AT) and water level (WL) were the two dominant variables impacting thermal stratification. AT affected the surface water temperature promoting the formation of thermal stratification, and high WLs …


Bigger Tides, Less Flooding: Effects Of Dredging On Barotropic Dynamics In A Highly Modified Estuary, David K. Ralston, Stefan Talke, W. Rockwell Geyer, Hussein A. M. Al-Zubaidi, Christopher K. Sommerfield Jan 2019

Bigger Tides, Less Flooding: Effects Of Dredging On Barotropic Dynamics In A Highly Modified Estuary, David K. Ralston, Stefan Talke, W. Rockwell Geyer, Hussein A. M. Al-Zubaidi, Christopher K. Sommerfield

Civil and Environmental Engineering Faculty Publications and Presentations

Since the late nineteenth century, channel depths have more than doubled in parts of New York Harbor and the tidal Hudson River, wetlands have been reclaimed and navigational channels widened, and river flow has been regulated. To quantify the effects of these modifications, observations and numerical simulations using historical and modern bathymetry are used to analyze changes in the barotropic dynamics. Model results and water level records for Albany (1868 to present) and New York Harbor (1844 to present) recovered from archives show that the tidal amplitude has more than doubled near the head of tides, whereas increases in the …


Decadal Topographic Change In The Mcmurdo Dry Valleys Of Antarctica: Thermokarst Subsidence, Glacier Thinning, And Transfer Of Water Storage From The Cryosphere To The Hydrosphere, J. S. Levy, Andrew G. Fountain, M. K. Obryk, J. Telling, Craig Glennie, M. Gooseff, David J. Van Horn Sep 2018

Decadal Topographic Change In The Mcmurdo Dry Valleys Of Antarctica: Thermokarst Subsidence, Glacier Thinning, And Transfer Of Water Storage From The Cryosphere To The Hydrosphere, J. S. Levy, Andrew G. Fountain, M. K. Obryk, J. Telling, Craig Glennie, M. Gooseff, David J. Van Horn

Geology Faculty Publications and Presentations

Recent local-scale observations of glaciers, streams, and soil surfaces in the McMurdo Dry Valleys of Antarctica (MDV) have documented evidence for rapid ice loss, glacial thinning, and ground surface subsidence associated with melting of ground ice. To evaluate the extent,magnitude, and location of decadal-scale landscape change in the MDV, we collected airborne lidar elevation data in 2014–2015 and compared these data to a 2001–2002 airborne lidar campaign. This regional assessment of elevation change spans the recent acceleration of warming and melting observed by long-term meteorological and ecosystem response experiments, allowing us to assess the response of MDV surfaces to warming …


Effects Of Substrate Depth And Precipitation Characteristics On Stormwater Retention By Two Green Roofs In Portland Or, Isaac Schultz, David Sailor, Olyssa Starry Jul 2018

Effects Of Substrate Depth And Precipitation Characteristics On Stormwater Retention By Two Green Roofs In Portland Or, Isaac Schultz, David Sailor, Olyssa Starry

University Honors College Faculty Publication and Presentations

Study Region: This study took place in Portland Oregon, a city of over 600,000 residents located in the Willamette Valley in the state of Oregon in the Pacific Northwest region of the United States. Portland experiences a temperate climate with Mediterranean features. Study Focus: Runoff patterns from two extensive green roofs with substrate depths of 75 and 125 mm, situated on a 5000 square meter retail store, were compared over a one year period. Precipitation, irrigation, and storm water discharge were continuously monitored and the performance of the green roofs for storm water control was investigated in detail. New Hydrological …


Winter Rain Versus Snow In Headwater Catchments: Responses Of An Unconfined Pumice Aquifer, South-Central Oregon, Usa, Michael L. Cummings, David A. Eibert Jan 2018

Winter Rain Versus Snow In Headwater Catchments: Responses Of An Unconfined Pumice Aquifer, South-Central Oregon, Usa, Michael L. Cummings, David A. Eibert

Geology Faculty Publications and Presentations

Winter precipitation in two headwaters catchments (elevation ~1600 m) in the rain shadow of the Cascades volcanic arc in south-central Oregon normally falls as snow. However, in water year 2015, winter precipitation fell mainly as rain. An eight year study of the unconfined pumice aquifer allowed inter-annual comparison of groundwater recharge during the freshet and discharge during the growing season. During these water years precipitation ranged from 67% (WY2014) to 132% (WY2017) of the 30 year average, and included the rain dominated winter of WY2015 when precipitation during the water year was 98% of the 30 year average. Change in …


Effects Of Water Level Increase On Phytoplankton Assemblages In A Drinking Water Reservoir, Yangdong Pan, Shijun Guo, Yuying Li, Wei Yin, Pengcheng Qi, Jainwei Shi, Lanqun Hu, Bing Li, Shengge Bi, Jingya Zhu Jan 2018

Effects Of Water Level Increase On Phytoplankton Assemblages In A Drinking Water Reservoir, Yangdong Pan, Shijun Guo, Yuying Li, Wei Yin, Pengcheng Qi, Jainwei Shi, Lanqun Hu, Bing Li, Shengge Bi, Jingya Zhu

Environmental Science and Management Faculty Publications and Presentations

Excessive water level fluctuation may affect physico-chemical characteristics, and consequently ecosystem function, in lakes and reservoirs. In this study, we assessed the changes of phytoplankton assemblages in response to water level increase in Danjiangkou Reservoir, one of the largest drinking water reservoirs in Asia. The water level increased from a low of 137 m to 161 m in 2014 as a part of the South–North Water Diversion Project. Phytoplankton assemblages were sampled four times per year before, during and after the water level increase, at 10 sites. Environmental variables such as total nitrogen as well as phytoplankton biomass decreased after …


A Bayesian Hierarchical Approach To Multivariate Nonstationary Hydrologic Frequency Analysis, C. Bracken, K. D. Holman, B. Rajagopalan, Hamid Moradkhani Jan 2018

A Bayesian Hierarchical Approach To Multivariate Nonstationary Hydrologic Frequency Analysis, C. Bracken, K. D. Holman, B. Rajagopalan, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

We present a general Bayesian hierarchical framework for conducting nonstationary frequency analysis of multiple hydrologic variables. In this, annual maxima from each variable are assumed to follow a generalized extreme value (GEV) distribution in which the location parameter is allowed to vary in time. A Gaussian elliptical copula is used to model the joint distribution of all variables. We demonstrate the utility of this framework with a joint frequency analysis model of annual peak snow water equivalent (SWE), annual peak flow, and annual peak reservoir elevation at Taylor Park dam in Colorado, USA. Indices of largescale climate drivers—El Ni~no Southern …


Bioassessment Of A Drinking Water Reservoir Using Plankton: High Throughput Sequencing Vs. Traditional Morphological Method, Wanli Gao, Zhaojin Chen, Yuying Li, Yangdong Pan, Jingya Zhu, Shijun Guo, Lanqun Hu, Jin Huang Jan 2018

Bioassessment Of A Drinking Water Reservoir Using Plankton: High Throughput Sequencing Vs. Traditional Morphological Method, Wanli Gao, Zhaojin Chen, Yuying Li, Yangdong Pan, Jingya Zhu, Shijun Guo, Lanqun Hu, Jin Huang

Environmental Science and Management Faculty Publications and Presentations

Drinking water safety is increasingly perceived as one of the top global environmental issues. Plankton has been commonly used as a bioindicator for water quality in lakes and reservoirs. Recently, DNA sequencing technology has been applied to bioassessment. In this study, we compared the effectiveness of the 16S and 18S rRNA high throughput sequencing method (HTS) and the traditional optical microscopy method (TOM) in the bioassessment of drinking water quality. Five stations reflecting different habitats and hydrological conditions in Danjiangkou Reservoir, one of the largest drinking water reservoirs in Asia, were sampled May 2016. Non-metric multi-dimensional scaling (NMDS) analysis showed …


Time Varying Parameter Models For Catchments With Land Use Change: The Importance Of Model Structure, Sahani Pathiraja, Daniela Anghileri, Paolo Burlando, Ashish Sharma, Lucy Marshall, Hamid Moradkhani Jul 2017

Time Varying Parameter Models For Catchments With Land Use Change: The Importance Of Model Structure, Sahani Pathiraja, Daniela Anghileri, Paolo Burlando, Ashish Sharma, Lucy Marshall, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

Rapid population and economic growth in South-East-Asia has been accompanied by extensive land use change with consequent impacts on catchment hydrology. Modelling methodologies capable of handling changing land use conditions are therefore becoming ever more important, and are receiving increasing attention from hydrologists. A recently developed Data Assimilation based framework that allows model parameters to vary through time in response to signals of change in observations is considered for a medium sized catchment (2880 km²) in Northern Vietnam experiencing substantial but gradual land cover change. We investigate the efficacy of the method as well as the importance of the chosen …


Parameterizing A Water-Balance Model For Predicting Stormwater Runoff From Green Roofs, Olyssa Starry, John Lea-Cox, Andrew Ristvey, Steven Cohan Dec 2016

Parameterizing A Water-Balance Model For Predicting Stormwater Runoff From Green Roofs, Olyssa Starry, John Lea-Cox, Andrew Ristvey, Steven Cohan

University Honors College Faculty Publication and Presentations

Crop coefficients (kc) were calculated for three different species of common green roof succulents from March to November in 2011, to parameterize the Food and Agricultural Organization of the United Nations (FAO) Penman-Monteith equation for use in a mechanistic green roof water-balance model. Seasonally averaged kc values for each species for 2011 were used to predict plant evapotranspiration (ET) in 2012. The adjusted FAO Penman-Monteith equation predicted the total annual ET within 3–13 mm, a substantial improvement over model predictions with kc set to 1, which overpredicted ET by 100 mm or more, depending on the species. The adjusted equation …


Tidal-Fluvial And Estuarine Processes In The Lower Columbia River: Ii. Water Level Models, Floodplain Wetland Inundation, And System Zones, David A. Jay, Amy B. Borde, Heida Diefenderfer Sep 2016

Tidal-Fluvial And Estuarine Processes In The Lower Columbia River: Ii. Water Level Models, Floodplain Wetland Inundation, And System Zones, David A. Jay, Amy B. Borde, Heida Diefenderfer

Civil and Environmental Engineering Faculty Publications and Presentations

Spatially varying water-level regimes are a factor controlling estuarine and tidal-fluvial wetland vegetation patterns. As described in Part I, water levels in the Lower Columbia River and estuary (LCRE) are influenced by tides, river flow, hydropower operations, and coastal processes. In Part II, regression models based on tidal theory are used to quantify the role of these processes in determining water levels in the mainstem river and floodplain wetlands, and to provide 21-year inundation hindcasts. Analyses are conducted at 19 LCRE mainstem channel stations and 23 tidally exposed floodplain wetland stations. Sum exceedance values (SEVs) are used to compare wetland …


The Influence Of Floodplain Restoration On Flow And Sediment Dynamics In An Urban River, Sangaralingam Ahilan, Mingfu Guan, Andrew Sleigh, Nigel G. Wright, Heejun Chang Jun 2016

The Influence Of Floodplain Restoration On Flow And Sediment Dynamics In An Urban River, Sangaralingam Ahilan, Mingfu Guan, Andrew Sleigh, Nigel G. Wright, Heejun Chang

Geography Faculty Publications and Presentations

A study of floodplain sedimentation on a recently restored floodplain is presented. This study uses a two-dimensional hydro-morphodynamic model for predicting flow and suspended-sediment dynamics in the downstream of Johnson Creek, the East Lents reach, where the bank of the river has been reconfigured to reconnect to a restored floodplain on a 0.26 km2 (26-ha) site. The simulation scenarios include 10-, 50-, 100- and 500-year event-based deposition modelling of flood events and long-term modelling using the 64 historical flood events between 1941 and 2014. Simulation results showed that the restored floodplain significantly attenuates the upstream flood peak by up …


Accommodation Space In A High-Wave-Energy Inner-Shelf During The Holocene Marine Transgression: Correlation Of Onshore And Offshore Inner-Shelf Deposits (0–12 Ka) In The Columbia River Littoral Cell System, Washington And Oregon, Usa, Curt D. Peterson, Dave C. Twichell, Michael C. Roberts, Sandy Vanderburgh, Steve W. Hostetler May 2016

Accommodation Space In A High-Wave-Energy Inner-Shelf During The Holocene Marine Transgression: Correlation Of Onshore And Offshore Inner-Shelf Deposits (0–12 Ka) In The Columbia River Littoral Cell System, Washington And Oregon, Usa, Curt D. Peterson, Dave C. Twichell, Michael C. Roberts, Sandy Vanderburgh, Steve W. Hostetler

Geology Faculty Publications and Presentations

The Columbia River Littoral Cell (CRLC), a high-wave-energy littoral system, extends 160 km alongshore, generally north of the large Columbia River, and 10–15 km in across-shelf distance from paleo-beach backshores to about 50 m present water depths. Onshore drill holes (19 in number and 5–35 m in subsurface depth) and offshore vibracores (33 in number and 1–5 m in subsurface depth) constrain inner-shelf sand grain sizes (sample means 0.13–0.25 mm) and heavy mineral source indicators (> 90% Holocene Columbia River sand) of the inner-shelf facies (≥ 90% fine sand). Stratigraphic correlation of the transgressive ravinement surface in onshore drill holes …


Exploring, Exploiting And Evolving Diversity Of Aquatic Ecosystem Models: A Community Perspective, Annette B.G. Janssen, George B. Arhonditsis, Arthur Beusen, Karsten Bolding, Louise Bruce, Jorn Bruggeman, Raoul-Marie Couture, Andrea S. Downing, J. Alex Elliott, Marieke A. Frassl, Gideon Gal, Daan J. Gerla, Matthew R. Hipsey, Fenjuan Hu, Stephen C. Ives, Jan H. Janse, Erik Jeppesen, Klaus D. Jöhnk, David Kneis, Xiangzhen Kong, Jan J. Kuiper, Moritz K. Lehmann, Carsten Lemmen, Deniz Özkundakci, Thomas Petzoldt, Karsten Rinke, Barbara J. Robson, René Sachse, Sebastiaan A. Schep, Martin Schmid, Huub Scholten, Sven Teurlincx, Dennis Trolle, Tineke A. Troost, Anne A. Van Dam, Luuk P.A. Van Gerven, Mariska Weijerman, Scott A. Wells, Wolf M. Mooij Dec 2015

Exploring, Exploiting And Evolving Diversity Of Aquatic Ecosystem Models: A Community Perspective, Annette B.G. Janssen, George B. Arhonditsis, Arthur Beusen, Karsten Bolding, Louise Bruce, Jorn Bruggeman, Raoul-Marie Couture, Andrea S. Downing, J. Alex Elliott, Marieke A. Frassl, Gideon Gal, Daan J. Gerla, Matthew R. Hipsey, Fenjuan Hu, Stephen C. Ives, Jan H. Janse, Erik Jeppesen, Klaus D. Jöhnk, David Kneis, Xiangzhen Kong, Jan J. Kuiper, Moritz K. Lehmann, Carsten Lemmen, Deniz Özkundakci, Thomas Petzoldt, Karsten Rinke, Barbara J. Robson, René Sachse, Sebastiaan A. Schep, Martin Schmid, Huub Scholten, Sven Teurlincx, Dennis Trolle, Tineke A. Troost, Anne A. Van Dam, Luuk P.A. Van Gerven, Mariska Weijerman, Scott A. Wells, Wolf M. Mooij

Civil and Environmental Engineering Faculty Publications and Presentations

Here, we present a community perspective on how to explore, exploit and evolve the diversity in aquatic ecosystem models. These models play an important role in understanding the functioning of aquatic ecosystems, filling in observation gaps and developing effective strategies for water quality management. In this spirit, numerous models have been developed since the 1970s. We set off to explore model diversity by making an inventory among 42 aquatic ecosystem modellers, by categorizing the resulting set of models and by analysing them for diversity. We then focus on how to exploit model diversity by comparing and combining different aspects of …


Ensemble Prediction And Data Assimilation For Operational Hydrology, Dong-Jun Seo, Yuqiong Liu, Hamid Moradkhani, Albrecht Weerts Dec 2014

Ensemble Prediction And Data Assimilation For Operational Hydrology, Dong-Jun Seo, Yuqiong Liu, Hamid Moradkhani, Albrecht Weerts

Civil and Environmental Engineering Faculty Publications and Presentations

This special section in the Journal of Hydrology will discuss the need for advancing hydrologic ensemble prediction and DA.


Hydrogeology Of Pumice-Hosted Fens In The Winema-Fremont National Forest, Oregon, Usa, Michael L. Cummings, Jonathan Michael Weatherford, Leslie A. Mowbray Dec 2014

Hydrogeology Of Pumice-Hosted Fens In The Winema-Fremont National Forest, Oregon, Usa, Michael L. Cummings, Jonathan Michael Weatherford, Leslie A. Mowbray

Geology Faculty Publications and Presentations

Subaerial fallout from the Holocene eruption of Mount Mazama in the Oregon Cascade Range was deposited upon relatively low permeability volcanic and volcaniclastic bedrock and regolith. In the Walker Rim study area, erosion by ephemeral streams shortly after the eruption disrupted the lateral continuity of the 270 to 300 cm-thick pumice deposit. Co-evolution of the surface- and ground-water systems in a low-relief, low-slope landscape allowed diffuse groundwater discharge from the banks of the evolving stream system. Accumulation of organic material from groundwater dependent ecosystems at these sites of discharge allowed peat deposits to form on gently sloping erosion surfaces cut …


Toward A Reliable Prediction Of Seasonal Forecast Uncertainty: Addressing Model And Initial Condition Uncertainty With Ensemble Data Assimilation And Sequential Bayesian Combination, Caleb Matthew Dechant, Hamid Moradkhani Jun 2014

Toward A Reliable Prediction Of Seasonal Forecast Uncertainty: Addressing Model And Initial Condition Uncertainty With Ensemble Data Assimilation And Sequential Bayesian Combination, Caleb Matthew Dechant, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

Uncertainties are an unfortunate yet inevitable part of any forecasting system. Within the context of seasonal hydrologic predictions, these uncertainties can be attributed to three causes: imperfect characterization of initial conditions, an incomplete knowledge of future climate and errors within computational models. This study proposes a method to account for all threes sources of uncertainty, providing a framework to reduce uncertainty and accurately convey persistent predictive uncertainty. In currently available forecast products, only a partial accounting of uncertainty is performed, with the focus primarily on meteorological forcing. For example, the Ensemble Streamflow Prediction (ESP) technique uses meteorological climatology to estimate …


Relationships Between Environmental Governance And Water Quality In A Growing Metropolitan Area Of The Pacific Northwest, Usa, Heejun Chang, Paul R. Thiers, Noelwah R. Netusil, J. Alan Yeakley, Gretchen Rollwagen-Bollens, Steve Bollens, Sonia Singh Apr 2014

Relationships Between Environmental Governance And Water Quality In A Growing Metropolitan Area Of The Pacific Northwest, Usa, Heejun Chang, Paul R. Thiers, Noelwah R. Netusil, J. Alan Yeakley, Gretchen Rollwagen-Bollens, Steve Bollens, Sonia Singh

Geography Faculty Publications and Presentations

We investigate relationships between environmental governance and water quality in two adjacent growing metropolitan areas in the western US. While the Portland, Oregon and Vancouver, Washington metro areas share many common biophysical characteristics, they have different land development histories and water governance structures, providing a unique opportunity for examining how differences in governance might affect environmental quality. We conceptualize possible linkages in which water quality influences governance directly, using monitoring efforts as a metric, and indirectly by using the change in the sale price of single-family residential properties. Governance may then influence water quality directly through riparian restoration resulting from …


Convergent Surface Water Distributions In U.S. Cities, Meredith K. Steele, James B. Heffernan, Neil D. Bettez, Jeannine Cavender-Bares, Peter M. Groffman, J. Morgan Grove, Sharon J. Hall, Sarah E. Hobbie, Kelli L. Larson, Jennifer L. Morse, Christopher Neill, Kristen C. Nelson, Jarlath O'Neil-Dunne, Laura A. Ogden, Diane E. Pataki, Colin Polsky, Rinku Roy Chowdhury Feb 2014

Convergent Surface Water Distributions In U.S. Cities, Meredith K. Steele, James B. Heffernan, Neil D. Bettez, Jeannine Cavender-Bares, Peter M. Groffman, J. Morgan Grove, Sharon J. Hall, Sarah E. Hobbie, Kelli L. Larson, Jennifer L. Morse, Christopher Neill, Kristen C. Nelson, Jarlath O'Neil-Dunne, Laura A. Ogden, Diane E. Pataki, Colin Polsky, Rinku Roy Chowdhury

Environmental Science and Management Faculty Publications and Presentations

Earth's surface is rapidly urbanizing, resulting in dramatic changes in the abundance, distribution and character of surface water features in urban landscapes. However,the scope and consequences of surface water redistribution at broad spatialscales are not well understood. We hypothesized that urbanization would lead to convergent surface water abundance and distribution: in other words, cities will gain or lose water such that they become more similar to each other than are their surrounding natural landscapes. Using a database of more than 1 million water bodies and 1 million km of streams, we compared the surface water of 100 US cities with …


A Review Of Urban Water Body Challenges And Approaches: (1) Rehabilitation And Remediation, Robert M. Hughes, Susie Dunham, Kathleen G. Maas-Hebner, J. Alan Yeakley, Carl B. Schreck, Michael Harte, Nancy Molina, Clinton C. Shock, Victor W. Kaczynski, Jeff Schaeffer Jan 2014

A Review Of Urban Water Body Challenges And Approaches: (1) Rehabilitation And Remediation, Robert M. Hughes, Susie Dunham, Kathleen G. Maas-Hebner, J. Alan Yeakley, Carl B. Schreck, Michael Harte, Nancy Molina, Clinton C. Shock, Victor W. Kaczynski, Jeff Schaeffer

Environmental Science and Management Faculty Publications and Presentations

We review how urbanization alters aquatic ecosystems, as well as actions that managers can take to remediate urban waters. Urbanization affects streams by fundamentally altering longitudinal and lateral processes that in turn alter hydrology, habitat, and water chemistry; these effects create physical and chemical stressors that in turn affect the biota. Urban streams often suffer from multiple stressor effects that have collectively been termed an “urban stream syndrome,” in which no single factor dominates degraded conditions. Resource managers have multiple ways of combating the urban stream syndrome. These approaches range from whole-watershed protection to reach-scale habitat rehabilitation, but the prescription …


Ce-Qual-W2 Model And Model Set-Up, Scott A. Wells Nov 2013

Ce-Qual-W2 Model And Model Set-Up, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

Conference presentation that provides background information on the CE-QUAL-W2 water modeling software, with examples of its use and instructions on set-up and application.