310 research outputs found
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Projected climate change impacts on water demand and supply for the City of Corvallis
A report to Carollo Engineers, Inc.This report provides an estimate of the impacts of climate change on factors affecting City of Corvallis (Corvallis) water demand and its primary water supply sources: the Willamette River and Rock Creek. The key climate-related changes (considered in isolation from other changes) are summarized below:
-- Projected higher summer temperatures and lower summer rainfall would increase water demand due to higher evaporative demand and desire for comfort during summer. Using irrigation of lawns as an example, approximately an additional 2 inches of water per unit area each summer may be necessary within 30 years, relative to a 1970-1999 baseline, if averaging over the available climate projections.
-- While flood magnitudes on the Willamette River are projected to increase, summer low flows are projected to decrease.
Both of these projected changes increase the risk of disruption of water supply from the Willamette River and increase the reliance on the management of upstream reservoirs to regulate flows for flood risk management during the wet season and to maintain sufficient supply for all needs (instream and consumptive) during the dry season. Little change is projected in annual water supply from Rock Creek, but future reductions in late spring flow may lead to a shorter time window of availability for water withdrawal.
Despite the critical importance of the quality of Corvallis’ water sources, the varying pathways through which climate change can influence harmful algal blooms (HABs) in the Willamette Valley have not been well quantified, though most projected changes (higher temperatures; higher erosion rates from more intense precipitation and large wildfires, and the associated increased nutrient loading in Oregon’s surface waters) point to a higher frequency of HABs. In addition to the impacts on water quantity, one additional conclusion of this report is that there exists a large gap in knowledge of the degree to which climate change will impact the quality of the sources of water upon which Corvallis, and other communities in the Willamette Basin, rely
Дух міста в добу глобалізації
У статті пропонується авторський варіант осмислення проблем формування та структурування міст з позиції філософської антропології. Зроблено спробу експлікації проблемного поля сучасного міста в контексті дослідження релігійної складової.The article is offered the author version of understanding the problems of forming and structuring town from the position of philosophical anthropology. The attempt of explication of problem field of contemporary town in the context of the religious component of research is done
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On the use of the Boussinesq equation for interpreting recession hydrographs from sloping aquifers
The method of recession analysis proposed by Brutsaert and Nieber (1977) remains one of the few analytical tools for estimating aquifer hydraulic parameters at the field scale and beyond. In the method, the recession hydrograph is examined as −dQ/dt = f(Q), where Q is aquifer discharge and f is an arbitrary function. The observed function f is parameterized through analytical solutions to the one-dimensional Boussinesq equation for unconfined flow in a homogeneous and horizontal aquifer. While attractive in its simplicity, as originally presented it is not applicable to settings where slope is an important driver of flow, or where hydraulic parameters vary greatly with depth. We compare analytical solutions to the linearized one-dimensional Boussinesq equation for a sloping aquifer to numerical solutions of the full nonlinear equation. The behavior of the nonlinear Boussinesq equation is also assessed when the aquifer is heterogeneous wherein the lateral saturated hydraulic conductivity k varies as a power law with height z above the impermeable layer (k ∼ z[superscript n] , n constant ≥ 0). All of the analytical solutions differ in key aspects from the nonlinear solution when plotted as −dQ/dt = f(Q) and thus are inappropriate for a Brutsaert and Nieber-type analysis. However, new analytical solutions for a sloping aquifer are derived “empirically” from the numerical simulations that are applicable during the late period of recession when the recession curve converges to −dQ/dt = aQ[superscript b] , where b = (2n + 1)/(n + 1) and a is a function of the dimensions and hydraulic properties of the aquifer.Keywords: Boussinesq, Recession analysis, Slopin
Value Landscape Engineering: identifying costs, water use, labor, and impacts to support landscape choice.
We present a spreadsheet model that identifies the costs, water, labor, fertilizer, pesticides, fuel, energy, carbon emissions, and particulates required of and generated by a user-specified residential or commercial landscape over its economic life. This life includes site preparation, materials purchase, installation, annual maintenance and replacing landscape features that wear out or die. Users provide a variety of site-descriptive information and the model queries an extensive database of landscape data to calculate costs, required inputs, and impacts. We verified model results against observations of water, labor, fertilizer, and fuel use over eight years at three landscapes in the Salt Lake City, Utah metropolitan region. We use the model to show tradeoffs in costs and required inputs for a predominately cool-season turfgrass landscape typical for Salt Lake City and other high desert, intermountain western United States cities and potential modifications to that typical landscape. Results highlight strategies water conservation programs can use to encourage property owners to install and adopt water-conserving landscape features and practices. Residential and commercial landscapers, landscape architects, contractors, and property owners can also model current and proposed landscapes and use results to identify a low-cost, low-input landscape that achieves their client’s or their own goals and values
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Effect of forecast skill on management of the Oregon coast coho salmon (Oncorhynchus kisutch) fishery
Better fisheries management is often given as one justification for research on improving forecasts of fish survival. However, the value gained from expected improvements in forecast skill in terms of achieving management goals is rarely quantified as part of research objectives. Using Monte Carlo simulations of population dynamics, we assessed the effect of forecast skill under two strategies for managing Oregon coast natural (OCN) coho salmon (Oncorhynchus kisutch). The first, or status quo, strategy is currently being used to rebuild threatened OCN coho populations. This strategy determines harvest based on both a forecasted marine survival rate and parental spawner abundance. The second strategy relies on a forecast of preharvest adult abundance to achieve a constant spawner escapement target. Performance of the status quo strategy was largely insensitive to forecast skill, while the second strategy showed sensitivity that varied with escapement target and specific performance metric. The results imply that effort towards improving forecasts is not justifiable solely on the basis of improved management under the status quo strategy, though it may be were the management strategy altered.Une meilleure gestion des ressources halieutiques est une des raisons communément évoquées pour justifier les recherches sur l’amélioration de la capacité de prévision de la survie du poisson. Cela dit, la quantification de la valeur dé-coulant des améliorations attendues de la capacité de prévision pour ce qui est de l’atteinte des objectifs de gestion est rare-
ment incluse dans les objectifs de recherche. En utilisant des simulations de Monte Carlo de la dynamique des populations, nous avons évalué l’effet de la capacité de prévision dans le contexte de deux stratégies de gestion du saumon coho (Onco-rhynchus kisutch) naturel de la côte de l’Oregon (OCN). La première stratégie, celle du statu quo, est actuellement utilisée pour reconstituer les populations menacées de saumon coho OCN. Selon cette stratégie, la récolte est établie en fonction des
prévisions concernant le taux de survie en mer et l’abondance de géniteurs parentaux. La deuxième stratégie repose sur la prévision de l’abondance des adultes avant la récolte pour en arriver à une cible d’échappée de géniteurs constante. Le ren-dement de la stratégie du statu quo s’est avéré peu sensible à la capacité de prévision, alors que la sensibilité de la deuxième stratégie variait selon la cible d’échappée et le paramètre de mesure du rendement utilisé. Ces résultats indiquent que l’amé-lioration de la gestion dans le contexte d’une approche axée sur le statu quo ne justifie pas, à elle seule, les efforts visant l’amélioration des prévisions, mais que ces efforts pourraient être justifiés si la stratégie de gestion était modifiée
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Seasonal Climate Variability and Change in the Pacific Northwest of the United States
Observed changes in climate of the U.S. Pacific Northwest since the early twentieth century were examined
using four different datasets. Annual mean temperature increased by approximately 0.6°–0.8°C from 1901 to
2012, with corroborating indicators including a lengthened freeze-free season, increased temperature of the
coldest night of the year, and increased growing-season potential evapotranspiration. Seasonal temperature
trends over shorter time scales (<50 yr) were variable. Despite increased warming rates in most seasons over
the last half century, nonsignificant cooling was observed during spring from 1980 to 2012. Observations show
a long-term increase in spring precipitation; however, decreased summer and autumn precipitation and increased
potential evapotranspiration have resulted in larger climatic water deficits over the past four decades.
A bootstrapped multiple linear regression model was used to better resolve the temporal heterogeneity of
seasonal temperature and precipitation trends and to apportion trends to internal climate variability, solar
variability, volcanic aerosols, and anthropogenic forcing. The El Niño-Southern Oscillation and the Pacific-North American pattern were the primary modulators of seasonal temperature trends on multidecadal time
scales: solar and volcanic forcing were nonsignificant predictors and contributed weakly to observed trends.
Anthropogenic forcing was a significant predictor of, and the leading contributor to, long-term warming;
natural factors alone fail to explain the observed warming. Conversely, poor model skill for seasonal precipitation
suggests that other factors need to be considered to understand the sources of seasonal precipitation
trends
Principled development of Workplace English Communication part 3: an Integrated Design and Appraisal Framework
Open access article. Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0) appliesBackground: An expanded skillset is needed to meet today’s shifting workplace demands, which involve collaboration with geographically distributed multidisciplinary teams. As the nature of work changes due to increases in automation and the elevated need to work in multidisciplinary teams, enhanced visions of Workplace English Communication (WEC) are needed to communicate with diverse audiences and effectively use new technologies. Thus, WEC is ranked as one of the top five skills needed for employability. Even so, results of employer surveys report that incoming employees lack communication competency (National Association of Colleges and Employers [NACE], 2018). To address this issue, with a focus on WEC teaching and assessment, we describe a framework used to guide the design of WEC modules. We suggest that conceptual frameworks can be used to inform the design process of the module. In this article, we illustrate one such conceptual framework: the Integrated Design and Appraisal Framework (IDAF). IDAF holds consequences of testing as one of its central elements to guide test design and development. It emphasizes categorically identifying and ecologically modeling variables impacting WEC in general and the writing context in particular. It emphasizes the need for developing clearly articulated construct models to underpin the assessment, as well as incorporating a foundational focus on fairness and social consequences into the design process and use of assessments.
Questions Addressed: In reference to the IDAF, our article addresses questions in the following three areas: the nature and benefits of an integrated design and appraisal approach to test design, development, and evaluation; the application of IDAF to complex communication tasks captured in formative assessment scenario-based modules of WEC; and the paramount importance of considering fairness and social consequences in the design and use of assessments administered to diverse populations. Thus, this article elaborates on the use of the IDAF to inform the design of WEC modules by explicitly articulating the needs of the test takers, the anticipated uses of the modules, and the contexts in which the modules would be used. Our questions are designed to address increasing complexities associated with the design of complex constructs such as WEC. This article describes considerations for the development of integrated learning and assessment modules for WEC. We start by reviewing principled assessment design frameworks, which have been used to inform the development of complex tasks across disciplines or fields. Following a description of WEC in terms of domain analysis and design patterns, we illustrate the application of the IDAF to inform the design of the modules. We conclude by providing an overview of our research questions and of how our article addressed them. We also discuss lessons learned with respect to the design of the prototype and the delicate balance of engaging in a principled design process that supports goals that empower students of diverse backgrounds to learn WEC.
Conclusions: This article illustrates the application of the IDAF to inform the design and development of WEC modules. This article contributes to the literature on WEC and complex assessments of hard-to-assess constructs more generally by offering a way of thinking about designing, assessing, and then evaluating the design and assessment of interactive educational modules for teaching complex communication knowledge and approaches.Ye
Principled development of Workplace English Communication part 2: Expanded Evidence-Centered Design and Theory of Action frameworks
Open access article. Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International license (CC BY NC-ND 4.0) appliesBackground: In today’s rapidly evolving world, technological pressures coupled with changes in the nature of work increasingly require individuals to use advanced technologies to communicate and collaborate in geographically distributed multidisciplinary teams. These shifts present the need to teach and assess an expanded set of knowledge, skills, and attitudes, including how to communicate at work in collaborative environments using diverse forms of technology. They also present the opportunity to create novel forms of instructional materials and forms of assessment that extend the more traditionally used summative assessments to assessments used for learning and instruction. This design process can be facilitated through the use of conceptual frameworks employed to guide assessment design and development. Their use is important to support more expansive and complex design goals emerging in the design of assessments of 21st century skills such as Workplace English Communication (WEC). In this article, we reflect on an evolving WEC construct needed for today’s economy and discuss implications for expanding how we teach and assess it using formative assessments for learning. We then discuss the features of the expanded Evidence-Centered Design for learning and assessment systems (e-ECD) and Theory of Action (ToA) frameworks and illustrate their integrative application to inform the design and development of WEC training modules (or resources). We conclude with suggestions for next steps in this line of research.
Questions Addressed: In reference to the e-ECD and ToA frameworks, our article addresses questions in two areas. We illustrate the benefits of using the ToA to explicitly identify the components of an assessment, its action mechanisms, stakeholders’ needs, score-based decisions and their impact, and the services designed for test takers and users. We illustrate the benefits of using the e-ECD framework to guide design efforts in principled ways to enable consideration of both key elements that relate evidentiary elements relevant to the construct, aspects of learning and assessment, and measurement models. Consideration of these frameworks is important to design assessments and make sense of the evidence for meaningful interpretation of students’ results.
Conclusions: This article illustrates the application of conceptual (e.g., the e-ECD and ToA) frameworks that can be used to inform the design and development of similar modules for complex tasks of 21st century skills. This article contributes to the literature on WEC and complex assessments of hard-to-assess constructs more generally by offering a way of thinking about designing, assessing, and then evaluating the design and assessment of interactive educational modules for teaching complex communication knowledge and abilities while remaining attentive to (negative) consequences associated with the stakeholders designing, developing, and using the assessments.Ye
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A unified approach for process-based hydrologic modeling: 1. Modeling concept
This work advances a unified approach to process-based hydrologic modeling to enable controlled and systematic evaluation of multiple model representations (hypotheses) of hydrologic processes and scaling behavior. Our approach, which we term the Structure for Unifying Multiple Modeling Alternatives (SUMMA), formulates a general set of conservation equations, providing the flexibility to experiment with different spatial representations, different flux parameterizations, different model parameter values, and different time stepping schemes. In this paper, we introduce the general approach used in SUMMA, detailing the spatial organization and model simplifications, and how different representations of multiple physical processes can be combined within a single modeling framework. We discuss how SUMMA can be used to systematically pursue the method of multiple working hypotheses in hydrology. In particular, we discuss how SUMMA can help tackle major hydrologic modeling challenges, including defining the appropriate complexity of a model, selecting among competing flux parameterizations, representing spatial variability across a hierarchy of scales, identifying potential improvements in computational efficiency and numerical accuracy as part of the numerical solver, and improving understanding of the various sources of model uncertainty.Keywords: unified model, hydrometeorology, scaling behavio
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Detection and Attribution of Observed Changes in Northern Hemisphere Spring Snow Cover
Abstract: Significant declines in spring Northern Hemisphere (NH) snow cover extent (SCE) have been observed over the last five decades. As one step toward understanding the causes of this decline, an optimal fingerprinting technique is used to look for consistency in the temporal pattern of spring NH SCE between observations and simulations from 15 global climate models (GCMs) that form part of phase 5 of the Coupled Model Intercomparison Project. The authors examined simulations from 15 GCMs that included both natural and anthropogenic forcing and simulations from 7 GCMs that included only natural forcing. The decline in observed NH SCE could be largely explained by the combined natural and anthropogenic forcing but not by natural forcing alone. However, the 15 GCMs, taken as a whole, underpredicted the combined forcing response by a factor of 2. How much of this underprediction was due to underrepresentation of the sensitivity to external forcing of the GCMs or to their underrepresentation of internal variability has yet to be determined.This is the publisher’s final pdf. The published article is copyrighted by the American Meteorological Society and can be found at: http://www.ametsoc.org/pubs/journals/jcli/.Keywords: Statistical techniques, Climate models, Anthropogenic effects, Snow, Northern Hemispher
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