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1
Ishak, Asnor Muizan. "Hydrological simulation aided by numerical weather prediction model." Thesis, University of Bristol, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.559471.
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In many water resources and hydrological projects, it is not always possible to get access to in-situ long-term time series weather measurements, especially for ungauged catchments. Even with gauged catchments, it is common that only rain gauge and river level data are available; other weather variables such as solar radiation, wind speed, surface temperature, surface air pressure and relative humidity are usually missing and if available are generally not in continuous form. These weather variables are basic building blocks of the global hydrological cycle that includes evapotranspiration (ET 0) and runoff estimation. The ET 0 and runoff can be estimated from the Penman-Monteith equation and rainfall runoff modeling respectively. This thesis explored a potential application of downscaled global reanalysis weather data using Pennsylvania State University-National Center for Atmospheric Research Mesoscale Model 5 (MMS). MMS is able to downscale the global weather data down to a much finer resolution in space and time for use in local hydrological investigations. The exploration of downscaling the ERA-40 reanalysis data to the Brue catchment in Southwest England and the assessment of the relevant weather variables in comparison with those measured at the ground was described in the thesis. However, there is a problem in using these selected weather variables in hydrological processes due to uncertainties obtained from the mesoscale modelling. Therefore, this thesis focused on the improvement of the weather variables from the dynamical downscaling and statistical modeling. The improvement of dynamic downscaling with the MMS cumulus parameterization schemes (CPSs) by changing the horizontal and vertical resolutions are presented in this thesis for rainfall estimation. Meanwhile, the error correction with statistical models is an attempt to hybridize MMS with two regression models ( the multiple linear regression (MLR) and the nonlinear regression (NLR)) and two artificial intelligence systems (the artificial neural networks (ANNs) and the support vector machines (SVMs)). This exploration is to tackle the errors between the MMS downscaled and observed data in addition to other MMS derived hydro- meteorological parameters. The hold-out validation with a forward selection method was employed as an input variable selection procedure to examine the model generalization errors in these statistical models. Upon the implementation of the error correction technique of weather variables, a comparative study of runoff simulation via the PDM model was completed between the MMS downscaled, corrected and observed data. This thesis also presents a sensitivity analysis of six weather variables to ET 0 estimation and runoff simulation through various combinations of the Penrnan-Monteith equation and Probability Distributed Model (PDM}inputs. Finally, by this assessment of several case studies in this thesis, it has shown that the enhanced MMS modeling scheme with the correction approaches substantially improves the forecasted weather variables over the study area which is important for the hydrological processes.
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Zhang, Hongbin. "Urban flood simulation by coupling a hydrodynamic model with a hydrological model." Thesis, University of Newcastle upon Tyne, 2015. http://hdl.handle.net/10443/2797.
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This work introduces a new integrated flood modelling tool in urban areas by coupling a hydrodynamic model with a hydrological model in order to overcome the drawbacks of each individual modelling approach, i.e. high computational costs usually associated with hydrodynamic models and less detailed physical representations of the underlying flow processes corresponding to hydrological models. Crucial to the simulation process is to first divide the catchment hydraulic and hydrological zones where the corresponding model is then applied. In the hydrological zones that have more homogeneous land cover and relatively simple topography, a conceptual lumped model is applied to obtain the surface runoff, which is then routed by a group of pre-acquired ‘unit hydrographs’ to the zone border, for high-resolution flood routing in the hydraulic zones with complex topographic features, including roads, buildings, etc. In hydraulic zones, a full 2D hydrodynamic model is applied to provide more detailed flooding information e.g. water depth, flow velocity and arrival time. The new integrated flood modelling tool is validated in Morpeth, the North East of England by reproducing the September 2008 flood event during which the town was severely inundated following an intense rainfall event. Moreover, the coupled model is investigated and evaluated according to the effects from temporal and spatial resolutions, friction, rainfall, infiltration, buildings and coupling methods. In addition, the model is also employed to implement flood damage estimations with different scenarios of the upstream storage and flood defences in the town centre. Whilst producing similar accuracy, the new model is shown to be much more efficient compared with the hydrodynamic model depending on the hydrological zone percentage. These encouraging results indicate that the new modelling tool could be robust and efficient for practitioners to perform flood modelling, damage estimation, risk assessment and flood management in urban areas and large-scale catchments.
3
Vilariño, Daniel R. "Hydrologic calibration of the Cub Run Watershed using the PC version of the Hydrological Simulation Program - FORTRAN (HSPF)." Thesis, Virginia Tech, 1996. http://hdl.handle.net/10919/44438.
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The Hydrological Simulation Program - FORTRAN (HSPF) in its personal computer version, release 10.10, was used to perform the hydrological simulation of a sub-watershed of the Occoquan River drainage basin. The sub-watershed selected was the Cub Run Watershed located in the northern area of the Occoquan River catchment. A model in the form of a User Control Input (UCI) file was prepared. The Cub Run Watershed was analyzed considering its geological, edaphic and weather characteristics, and segmented accordingly. The model was calibrated to adjust simulated results to observed data. Several calibration runs were executed and a final run was done considering a further segmented watershed. The simulation results were good even when not all the desired data could be found. The annual percent difference between the best calibration run and the observed results was 21.28%. The ten-month percent difference, excluding June and July, was 5.82 %. The first value is a fair result for hydrologic calibration, the second value is an excellent result for the same type of calibration. Additional segmentation did not further improve the results obtained during the best calibration run. Differences in the calibration when considering just a pervious segment or two segments (one pervious and one impervious) could be noted, indicating the importance of considering impervious surfaces for the simulation. HSPF reacted quite logically to variations in the calibration parameters and the results from those variations could be predicted beforehand. In summary, the PC version of HSPF was demonstrated to be a good management tool for the hydrological simulation of this watershed.
Master of Science
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Parsons, J. S. "A simulation model for subsurface and overland flow down a hillside in the Crimple Beck, N. Yorkshire." Thesis, University of Leeds, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376984.
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Zhang, Fangli. "A particle-set distributed hydrological model for the dynamic simulation of surface runoff." HKBU Institutional Repository, 2017. https://repository.hkbu.edu.hk/etd_oa/472.
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1.1\xThis study proposed a particle-set distributed hydrological model for the dynamic simulation of rainfall-runoff process. With the supports of remote sensing, GIS, terrain analysis and distributed computing techniques, a representation-simplified and physically-based high-performance watershed framework has been developed. It simplifies the underlying watershed with a flow path network model, and represents the moving surface flow with independent runoff particles.;1.2\xThe original idea was to investigate a real-time modeling system for the space-time dynamics of increasingly frequent extreme rainfall events. Short-term heavy rains may cause further damages by spawning floods and landslides. It is quite essential to understand how the rainfall water moves across the watershed surface as early as possible. A modelling system with high-performance in simulation efficiency and space-time prediction accuracy would be very desirable.;1.3\xWatershed modeling is the primary way to explore the hydrological cycle at a local scale. Existing models are classified as empirical lumped, conceptual semi-distributed and physically-based distributed models. The first two types of models have focused more on predicting outlet discharges rather than estimating spatiotemporal flow dynamics. The application of physically-based models has always been hampered by some common shortcomings like over-parameterization, inflexibility and computational burden. With the increasing support from terrain analysis and parallel computing techniques, a number of previous studies have made some efforts to improve the performance in dynamic and real-time simulation. However, research gaps still exist in realistic representation, physical description and real-time simulation.;1.4\xThis study, therefore, developed the particle-set modeling system on the basis of flow path network model. This one-dimensional topological structure was created beforehand to represent the three-dimensional watershed, and a series of particle beams were dynamically generated to simulate the surface flow. Under the control of flow velocities, these runoff particles would keep on moving along with the flow paths, which can represent the spatial distributions of surface water in time.;1.5\xTo validate the proposed particle-set framework, a prototype of particle-set system was implemented by programming methods with the assistance of third-party platforms. Three experiments were undertaken to respectively evaluate the performance in prediction accuracy, simulation efficiency and parameter sensitivity. More specifically, a total of 10 rainfall events and up to 128 computer processors were tested. In addition, the influences of underlying spatial scale and source sampling density on hydrological responses were explored with comparative tests.;1.6\xThe accuracy validation comes in two parts, the representation loss in terrain analysis, and the discharge error in hydrological modeling. The experimental results indicate that the TIN-based flow path network has maintained the terrain features at a very high level with much less data storage, and the particle-set framework has achieved quite acceptable predictions of outlet discharges. Besides, the efficiency evaluation concerns with two aspects, parallel portion and parallel efficiency. The speed-up results indicate that about 99% of the computational workloads can be computed in parallel, and the particle-based scheme can achieve almost the ideal parallel efficiency. In addition, the sensitivity test focuses also on two parameters, underlying spatial scale and source sampling density. The preliminary results show that the particle-set model has shown a good reliability and stability as scale gets coarser or density becomes sparser.;1.7\xThis study will contribute to the understanding of short-term rainfall-runoff events at a basin scale. The particle-set distributed hydrological model has been proven to provide real-time spatio-temporal dynamics of surface flow. Further studies would still be required to apply it to real world scenarios.;1.8\xKeywords: terrain analysis, watershed hydrology, rainfall-runoff process, flow path network, particle system, parallel computing
6
Tondu, Yohann. "Simulation of the Paris 1910 flood with a lumped hydrological model: the influence of frozen soil." Thesis, KTH, Vattendragsteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-96310.
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In 1910, Paris experienced its biggest flood in the 20th century. In 2010, for the anniversary of this event – supposed to happen every 100 years ! – the flood prediction model that is now used on the Seine basin was tested on its simulation,… and failed to reproduce the observed flood volume. This paper will try to explain, and correct, such disappointing results. Many hypotheses have been tested and based on their results, it has been decided to develop a frost module in order to assess the influence of this phenomenon – that is not taken into account by the lumped hydrological model that is used – on the flood formation. A soil temperature model using air temperature as input data was also designed because soil temperature data were not available in 1910. The addition of the frost module did not, however, bring many improvements to the 1910 flood simulation because frost is a too rare phenomenon on the Seine basin for the module to be correctly calibrated. However, new perspectives are presented to continue the research on this phenomenon.
7
Wang, Chen. "Simulation and Evaluation of Stream flow and Pesticide Prediction in Orestimba Creek Watershed using AnnAGNPS Model." OpenSIUC, 2014. https://opensiuc.lib.siu.edu/theses/1564.
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Pesticides have been recognized as one major agricultural non-point source (NPS) pollution to the environment and surface water in United States. Numerous mathematical models have been developed over the last decades to simulate the fate and transport of NPS at watershed scale. Geographic Information System (GIS) combined with models extends the spatial and temporal scopes of the research by integrating a variety of climates, soils, land covers, and management practices. The Annualized Agricultural Nonpoint Source model (AnnAGNPS) has received considerable attention in the United States for estimating runoff, sediment yield, pesticide and nutrients transport from ungauged agricultural watershed. However, few studies have been conducted on pesticide loading prediction in surface water using AnnAGNPS. In this study, the AnnAGNPS model was calibrated and validated for prediction of stream flow and chlorpyrifos loading for an agricultural dominated watershed of Orestimba Creek, in Central Valley, California. Large amounts of chlorpyrifos are applied to almonds, walnuts and other stone-fruit orchards in this area every year, which caused significant concern regarding their contamination to the San Joaquin River. Variety of data obtained from multiple sources were utilized as model input, including climate, land use, topology, soil, crop management and schedule, non-crop data, and pesticide. The model's performance was quantitatively analyzed using mean, standard deviation, coefficient of determination (r2), coefficient of efficiency (NSE), and root mean square error (RMSE). Model's prediction was considered to be unsatisfactory if NSE < 0.36, satisfactory if 0.36 < NSE < 0.75 and good if NSE > 0.75. Monthly stream flow discharge prediction was satisfactory and fit the observed data during model calibration mode. The prediction had major improvement in validation mode with modified curve number and rainfall interception values (r2 = 0.78 and NSE = 0.77). The AnnAGNPS predictions of chlorpyrifos concentrations in runoff water were unsatisfactory in both calibration and validation modes. Predicted chlorpyrifos concentrations at rainfall events were 1/1000 of observed data and it was impossible to improve the results through any type of calibration. The overall results suggested the model's poor performance was most likely a result of coarse sampling resolution of observed chlorpyrifos concentrations and lack of irrigation data.
8
Garcia, Luis Jimenez, Guzman Osnar Iruri, and Sissi Santos Hurtado. "Hazard map based on the simulation of sludge flow in a two-dimensional model, Case Quebrada Malanche-Punta Hermosa -Lima-Perú." Institute of Electrical and Electronics Engineers Inc, 2020. http://hdl.handle.net/10757/656417.
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El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado.This research presents the numerical simulation to reproduce the transport and deposition processes of the sludge flow on March 15, 2017, strongly impacting the town of Pampapacta in Punta Hermosa-Peru.The debris flow initiation process in the basin was represented by hydrographs obtained from the estimated volumes of stormwater runoff and solid materials. The sludge flow was modeled in Flo2D to calculate hazard maps with the discharge event and others with different return periods.The numerical simulation results show acceptable results in relation to what happened. The model used to assess the hazard due to debris flow can predict and delineate, with acceptable precision, potentially hazardous areas for a landslide. The application of the proposed methodology to assess the hazard of disasters due to debris flows in basins and streams is useful to understand the extent of the impact of the mud flow during extreme weather events, as well as to develop emergency plans and formulate disaster policies.
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Abdelnour, Alex Gabriel. "Assessing ecosystem response to natural and anthropogenic disturbances using an eco-hydrological model." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42899.
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The impact of natural and anthropogenic disturbances on catchment hydrological and biogeochemical dynamics are difficult or impossible to capture through experimentation or observation alone. Process-based simulation models can address this need by providing a framework for synthesizing data describing catchment responses to climate, harvest, fire, and other disturbances. However, existing models are either too simple to capture important process-level hydrological and biogeochemical controls on ecosystem responses to disturbance, or are too computationally expensive to simulate the local dynamics over large watershed areas, or require a high level of expertise to implement.
To this end, a spatially distributed, physically based, eco-hydrological model (VELMA: Visualizing Ecosystems for Land Management Assessments) that is both computationally efficient and relatively easy to implement is developed. VELMA is a state-of-the-art model with real-time visualization tools that shows temporal and spatial patterns of state and flux variables, and is used to address the effects of changes in climate, land-use, and other interacting stressors on multiple ecosystem services such as timber production, carbon sequestration, regulation of water quality and quantity and reduction of greenhouse gases at scales relevant to formulating management decisions.
In this study, VELMA was applied to the H.J. Andrews Experimental forest, an intensively studied watershed with observed daily temperature, precipitation, streamflow, and nutrient losses data. VELMA was first used to explore the factors that controls catchment response to forest harvest. Specifically, elucidate how forest harvest factors such as harvest location and amount control watershed hydrological and biogeochemical fluxes. Thereafter, VELMA was used to reconstruct and analyze the impact of two significant disturbance events − a stand replacing fire and a 100% clearcut − on vegetation and soil carbon and nitrogen dynamics. Finally, VELMA was used to explore the potential impact of climate change on catchment hydrological regime, site productivity and carbon and nitrogen dynamics at high spatial resolution relevant to formulating management decision.
The main insights from this study include: (1) streamflow, nutrient losses to the stream, and gaseous carbon and nitrogen losses to the atmosphere are strongly sensitive to the location of harvest as a result of the spatial variation in soil water content, plant nitrogen uptake, soil organic carbon decomposition, nitrification, and denitrification within the watershed, (2) forested riparian buffers reduce water and nutrient losses to the stream through plant transpiration, plant nitrogen uptake, soil storage, and soil microbial decomposition, (3) following fire and harvest, losses of N from the terrestrial system to the stream are tightly constrained by the hydrological cycle and driven mainly by wet-season rain events large enough to generate hydrologic connectivity and flushing of nutrients along hillslopes, (4) climate change strongly impacts the hydrological regime in the Pacific Northwest as a result of less snowpack, earlier snowmelt, higher winter streamflow, lower summer streamflow, and soil moisture deficit, and (5) climate change increases plant and soil biomass accumulation as a result of longer growing season and higher soil organic decomposition, reduce water quality by increasing the amount of nutrients that reach the stream, and transforms the ecosystem into a net source of carbon to the atmosphere.
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Kruk, N. S., Peter Hoffmann, and Armin Raabe. "Modeling of orographic precipitation events in South America to couple hydrological and atmospheric models; part 1: The simulation of rain with the Mesoscale Model GESIMA." Universitätsbibliothek Leipzig, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-222251.
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Globalmodelle sind aufgrund ihres groben Gitters (60 x 60 km) nur unzureichend in der Lage kleinskalige Prozesse (orographische Niederschlagsverstärkung) in der Atmosphäre aufzulösen. Mit Mesoskalenmodellen z.B. dem GESIMA (5 x 5 km) können deshalb die physikalische Grundlagen der Atmosphäre (Wolken- und Niederschlagsbildung) besser studiert und eine Kopplung mit hydrologischen Abflussmodellen erprobt werden. Zukünftig sieht dieses Projekt genau das vor, wobei der erste Teil, die Arbeit mit dem meteorologische Modell hier vorgestellt werden soll. Starkniederschlagserreignisse sind vielerorts auf der Welt mit charakteristischen Wetterlagen verbunden, die quasi über Tage unverändert ergiebigen Regen produzieren. Initialisiert mit den lokalen Vertikalprofilen aus Radiosondendaten, produzieren das prognostische Mesoskalenmodell GESIMA und das diagnostische Niederschlagsberechungsverfahren (MAXRR) maximale Regenmengen vergleichbarer GrößenordnungGlobal models are insufficient to solve small scale atmospheric processes (e.g. orographic precipitation) due to their gross resolution (60 x 60 km). With mesoscale models e.g. the GESIMA (5 x 5 km), the physical fundamentals of the atmosphere (formation of precipitation and clouds) can better be studied and a coupling with hydrological models be tested through. This project plans exactly, as a first step, the work with the cited meteorological model. Heavy rainfall events are connected with characteristic weather conditions in many places in the world which produce invariably rain quasi over days. Initialized with the local vertical profiles from radiosonde data, the prediction model GESIMA and the diagnostic model MAXRR produced rain quantities of comparable order of magnitude
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Kruk, N. S., Peter Hoffmann, and Armin Raabe. "Modeling of orographic precipitation events in South America to couple hydrological and atmospheric models; part 1: The simulation of rain with the Mesoscale Model GESIMA." Wissenschaftliche Mitteilungen des Leipziger Instituts für Meteorologie ; 37 = Meteorologische Arbeiten aus Leipzig … und Jahresbericht … des Instituts für Meteorologie der Universität Leipzig ; 11 (2006), S. 137-148, 2006. https://ul.qucosa.de/id/qucosa%3A15514.
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Globalmodelle sind aufgrund ihres groben Gitters (60 x 60 km) nur unzureichend in der Lage kleinskalige Prozesse (orographische Niederschlagsverstärkung) in der Atmosphäre aufzulösen. Mit Mesoskalenmodellen z.B. dem GESIMA (5 x 5 km) können deshalb die
physikalische Grundlagen der Atmosphäre (Wolken- und Niederschlagsbildung) besser studiert und eine Kopplung mit hydrologischen Abflussmodellen erprobt werden. Zukünftig sieht dieses Projekt genau das vor, wobei der erste Teil, die Arbeit mit dem meteorologische Modell hier vorgestellt werden soll. Starkniederschlagserreignisse sind vielerorts auf der Welt mit charakteristischen Wetterlagen verbunden, die quasi über Tage unverändert ergiebigen Regen produzieren. Initialisiert mit den lokalen Vertikalprofilen aus Radiosondendaten, produzieren das prognostische
Mesoskalenmodell GESIMA und das diagnostische Niederschlagsberechungsverfahren (MAXRR) maximale Regenmengen vergleichbarer Größenordnung.Global models are insufficient to solve small scale atmospheric processes (e.g. orographic precipitation) due to their gross resolution (60 x 60 km). With mesoscale models e.g. the GESIMA (5 x 5 km), the physical fundamentals of the atmosphere (formation of precipitation and clouds) can better be studied and a coupling with hydrological models be tested through. This project plans exactly, as a first step, the work with the cited meteorological model. Heavy rainfall events are connected with characteristic weather conditions in many places in the world which produce invariably rain quasi over days. Initialized with the local vertical profiles from radiosonde data, the prediction model GESIMA and the diagnostic model MAXRR produced rain quantities of comparable order of magnitude.
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SERRÃO, Edivaldo Afonso de Oliveira. "Aplicação do modelo SWAT na simulação hidrológica da bacia hidrográfica do rio Itacaiúnas-PA." Universidade Federal de Campina Grande, 2018. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/1756.
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CNPq
A bacia amazônica representa a maior extensão de florestas tropicais da Terra, exercendo significativa influência no clima local e global devido aos fluxos de energia e água na atmosfera. Exerce um papel importante no sequestro de carbono, bem como na emissão de água para a atmosfera que é fundamental na manutenção da própria floresta. Vários modelos hidrológicos têm sido aplicados para os biomas do Brasil, desde bases conceituais até a inserção dos SIG’s desenvolvendo os modelos distribuídos de base física. Dentre estes, o Soil and Water Assessment Tool – SWAT é um modelo hidrológico para grandes bacias e foi desenvolvido para simular processos que ocorrem em uma bacia hidrográfica. O objetivo desse trabalho foi utilizar o modelo SWAT para simular a vazão fluvial, alguns processos hidrológicos e risco de erosão da bacia hidrográfica do rio Itacaiúnas, sudeste do Estado do Pará, bem como sua calibração e validação do modelo para a bacia de estudo. Para isto foram necessários dados de uso e ocupação do solo, tipos de solo, declividade. Bem como dados climáticos e fluviométricos de precipitação, temperatura, vento, umidade relativa, radiação solar e vazão fluvial. Os resultados demostraram que para a análise do risco de erosão para a bacia hidrográfica do rio Itacaiúnas foi constatado que ás áreas de maior risco para erosão, foram ás regiões de maior altitude com solos de fácil degradação e com uma dinâmica de uso de solo elevada, sendo estas na jusante da bacia e na porção sul do município de Marabá. Na validação da vazão obtida através do modelo SWAT, foi observado que todos os índices estatísticos aplicados mostraram que a vazão simulada tive um bom desempenho, em relação a vazão observada na estação fluviométrica da ANA. Foi validado ainda a evapotranspiração potencial simulada pelo SWAT, a partir de outros dois métodos, Linacre e Turc e observou-se que todos os índices estatísticos aplicados a evapotranspiração simulada com SWAT tive um bom desempenho em relação aos outros dois métodos de estimar evapotranspiração. Já na comparação dos métodos de Linacre teve um menor desempenho, em relação ao método de Turc, haja visto que na estimativa feita por Turc é levado em consideração radiação solar, o que torna o método mais robusto em relação a Linacre. Logo o modelo SWAT teve um bom desempenho em simular a vazão, evapotranspiração e outros processos hidrológicos para a bacia hidrográfica do rio Itacaiúnas e pode ser uma fundamental ferramenta no monitoramento hidrológico dessa bacia, além de auxiliar os tomadores de decisões em uma boa gestão dos seus recursos.
The Amazon basin represents the largest expanse of tropical rainforests on Earth, exerting significant influence on the local and global climate due to the energy and water fluxes in the atmosphere. It plays an important role in carbon sequestration as well as in the emission of water into the atmosphere that is essential in maintaining the forest itself. Several hydrological models have been applied to the biomes of Brazil, from conceptual bases to the insertion of the GIS, developing the distributed models of physical base. Among these, the Soil and Water Assessment Tool - SWAT is a hydrological model for large basins and was developed to simulate processes that occur in a watershed. The objective of this work was to use the SWAT model to simulate river flow, some hydrological processes and risk of erosion of the Itacaiúnas river basin, southeast of the State of Pará, as well as its calibration and validation of the model for the study basin. For this, data on land use and occupation, soil types and slope were required. As well as climatic and fluviometric data of precipitation, temperature, wind, relative humidity, solar radiation and river flow. The results showed that for the analysis of the erosion risk for the Itacaiúnas river basin, it was found that the areas with the highest risk for erosion were the highest altitude areas with easily degraded soils and a high soil use dynamics, being these downstream of the basin and in the southern portion of the municipality of Marabá. In the validation of the flow obtained through the SWAT model, it was observed that all the applied statistical indices showed that the simulated flow had a good performance, in relation to the flow observed in the fluviometric station of the ANA. It was also validated the potential evapotranspiration simulated by SWAT, from two other methods, Linacre and Turc, and it was observed that all the statistical indices applied to simulated evapotranspiration with SWAT performed well in relation to the other two methods of estimating evapotranspiration. In the comparison of the methods of Linacre had a lower performance, in relation to the method of Turc, since in the estimation made by Turc is taken into consideration solar radiation, which makes the method more robust in relation to Linacre. The SWAT model performed well in simulating flow, evapotranspiration and other hydrological processes for the Itacaiúnas river basin and can be a fundamental tool in the hydrological monitoring of this basin, besides helping decision-makers in a good way. management of its resources.
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Sabetraftar, Karim, and Karim Sabetraftar@anu edu au. "The hydrological flux of organic carbon at the catchment scale: a case study in the Cotter River catchment, Australia." The Australian National University. Centre for Resource and Environmental Studies, 2005. http://thesis.anu.edu.au./public/adt-ANU20070502.141450.
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Existing terrestrial carbon accounting models have mainly investigated atmosphere-vegetationsoil
stocks and fluxes but have largely ignored the hydrological flux of organic carbon. It is
generally assumed that biomass and soil carbon are the only relevant pools in a landscape
ecosystem. However, recent findings have suggested that significant amounts of organic carbon
can dissolve (dissolved organic carbon or DOC) or particulate (particulate organic carbon or
POC) in water and enter the hydrological flux at the catchment scale. A significant quantity of
total organic carbon (TOC) sequestered through photosynthesis may be exported from the
landscape through the hydrological flux and stored in downstream stocks.¶
This thesis presents a catchment-scale case study investigation into the export of organic carbon
through a river system in comparison with carbon that is produced by vegetation through
photosynthesis. The Cotter River Catchment was selected as the case study. It is a forested
catchment that experienced a major wildfire event in January 2003. The approach is based on an
integration of a number of models. The main input data were time series of in-stream carbon
measurements and remotely sensed vegetation greenness. The application of models to
investigate diffuse chemical substances has dramatically increased in the past few years because
of the significant role of hydrology in controlling ecosystem exchange. The research firstly
discusses the use of a hydrological simulation model (IHACRES) to analyse organic carbon
samples from stream and tributaries in the Cotter River Catchment case study. The IHACRES
rainfall-runoff model and a regionalization method are used to estimate stream-flow for the 75
sub-catchments. The simulated streamflow data were used to calculate organic carbon loads
from concentrations sampled at five locations in the catchment.¶
The gross primary productivity (GPP) of the vegetation cover in the catchment was estimated
using a radiation use efficiency (RUE) model driven by MODIS TERRA data on vegetation
greenness and modeled surface irradiance (RS). The relationship between total organic carbon
discharged in-stream and total carbon uptake by plants was assessed using a cross-correlation
analysis.¶
The IHACRES rainfall-runoff model was successfully calibrated at three gauged sites and
performed well. The results of the calibration procedure were used in the regionalization method
that enabled streamflow to be estimated at ungauged locations including the seven sampling
sites and the 75 sub-catchment areas. The IHACRES modelling approach was found appropriate
for investigating a wide range of issues related to the hydrological export of organic carbon at
the catchment scale. A weekly sampling program was implemented to provide estimates of
TOC, DOC and POC concentrations in the Cotter River Catchment between July 2003 and June
2004. The organic carbon load was estimated using an averaging method.¶
The rate of photosynthesis by vegetation (GPP) was successfully estimated using the radiation
use efficiency model to discern general patterns of vegetation productivity at sub-catchment
scales. This analysis required detailed spatial resolution of the GPP across the entire catchment
area (comprising 75 sub-catchment areas) in addition to the sampling locations. Important
factors that varied at the catchment scale during the sampling period July 2003 June 2004,
particularly the wildfire impacts, were also considered in this assessment.
¶
The results of the hydrologic modelling approach and terrestrial GPP outcome were compared
using cross correlation and regression analysis. This comparison revealed the likely proportion
of catchment GPP that contributes to in-stream hydrological flux of organic carbon. TOC Load
was 0.45% of GPP and 22.5 - 25% of litter layer. As a result of this investigation and giving due
consideration to the uncertainties in the approach, it can be concluded that the hydrological flux
of organic carbon in a forested catchment is a function of gross primary productivity.
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Tetsoane, S. T., Y. E. Woyessa, and W. A. Welderufael. "Evaluation of the SWAT model in simulating catchment hydrology : case study of the Modder River Basin." Interim : Interdisciplinary Journal, Vol 13, Issue 3: Central University of Technology Free State Bloemfontein, 2013. http://hdl.handle.net/11462/313.
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Published ArticleThis paper presents the set-up and the performance of the SWAT model in the Modder River Basin. Two techniques widely used, namely quantitative statistics and graphical techniques, in evaluating hydrological models were used to evaluate the performance of SWAT model. Three quantitative statistics used were, Nash-Sutcliffe efficiency (NSE), present bias (PBIAS), and ratio of the mean square error to the standard deviation of measured data (RSR). The performance of the model was compared with the recommended statistical performance ratings for monthly time step data. The model performed well when compared against monthly model performance ratings during calibration and validation stage.
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Warscher, Michael [Verfasser], and Harald [Akademischer Betreuer] Kunstmann. "Performance of Complex Snow Cover Descriptions in a Distributed Hydrological Model System and Simulation of Future Snow Cover and Discharge Characteristics: A Case Study for the High Alpine Terrain of the Berchtesgaden Alps / Michael Warscher. Betreuer: Harald Kunstmann." Augsburg : Universität Augsburg, 2015. http://d-nb.info/1079793763/34.
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Hollanda, Maycon Patricio de. "Avaliação do topmodel em microbacia hidrográfica no município de Alegre, ES." Universidade Federal do Espírito Santo, 2012. http://repositorio.ufes.br/handle/10/6537.
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Previous issue date: 2012-12-19A utilização não sustentável dos recursos naturais tem gerado condições de escassez ou até mesmo esgotamento de alguns destes recursos. A água é um dos recursos naturais mais ameaçados pela exploração não sustentável. O estudo em bacias hidrográficas possibilita a integração dos fatores que condicionam a qualidade e a quantidade dos recursos hídricos, com os seus reais condicionantes físicos e antrópicos. A modelagem matemática constitui uma importante ferramenta para o gerenciamento dos recursos hídricos e o estudo geográfico de bacias hidrográficas. Do exposto, objetivou-se, avaliar a aplicabilidade do TOPMODEL para simular a vazão máxima (Qmáx), lâmina de escoamento superficial (LES) e hidrogramas de escoamento superficial em eventos de precipitação na microbacia hidrográfica do córrego Jaqueira (MCJ). A área de estudo possui 0,22 km², cinco tipos de uso e cobertura do solo, e um rio perene. Os dados de entrada do modelo constituíram-se do Indice topográfico, gerado a partir do MNT com resolução de 7m X 7m, da capacidade de água disponível na zona radicular, obtida por meio da média ponderada de cada valor para cada cobertura do solo, do déficit inicial de umidade na zona radicular, sendo considerado como 40% do SRmáx, da velocidade de propagação em canal, calculado a partir do tempo de concentração, e do armazenamento exponencial e da transmissividade efetiva do solo, ambos obtidos em literatura. Foram escolhidos 20 eventos durante o período de 19 de julho de 2009 a 28 de dezembro de 2011, no qual foram escolhidos de forma aleatória 6 eventos para calibração e 14 eventos para validação do modelo. Os eventos simulados no processo de calibração mostrou tendência de subestimar a Qmáx e LES em média 71% e 51%, respectivamente, ao final do processo foi calculado a média dos parâmetros de entrada tendo como critério os valores dos eventos que apresentaram valores positivos de eficiência, para serem utilizados no processo de validação. Após simular os 14 eventos destinados ao processo de validação do modelo, observou-se a tendência do modelo em simular 4 tipos de hidrogramas, que são, eventos em que os valores de Qmáx e LES foram subestimados em média de 50%, eventos que apresentam simulações com dois picos de Qmáx, em que o primeiro pico é subestimado e o segundo superestimado, eventos que apresentaram os melhores valores de eficiência com um pico bem definido, e eventos que apresentaram os piores valores de eficiência. Sendo que em resumo o modelo subestimou a Qmáx em 71% dos eventos e a LES em 51% dos eventos. Cabe destacar os eventos 6, 10 e 14 onde apresentaram eficiência acima de 0,70, e os eventos 9 e 11,em que por não terem suas amplitudes de intensidade de precipitação englobadas no processo de calibração apresentaram os piores resultados entre todos os eventos de validação analisados. Apesar do TOPMODEL apresentar baixa eficiência em diversas simulações dos hidrogramas de vazão de escoamento superficial, o modelo é promissor na modelagem dos hidrogramas, uma vez que os valores de vazão analisados na MCJ são muito pequenos
The unsustainable use of natural resources has generated conditions of scarcity or even exhaustion of some of these resources. Water is a natural resource most threatened by unsustainable exploration. The study watersheds enables integration of the factors that influence the quality and quantity of water resources, with its real physical and human constraints. Mathematical modeling is an important tool for the management of water resources and geographical study watershed. From the above, our aim was to evaluate the applicability of TOPMODEL to simulate the maximum flow (Qmáx), blade runoff (LES) and the runoff hydrographs for rainfall events in the microbasin hydrographic Jaqueira (MCJ). The study area has 0.22 km ², five types of land use and land cover, and a perennial river. The input data of the model consisted of topographic index, generated from the DEM with resolution of 7m x 7m, the available water capacity in the root zone, obtained by weighted average of each value for each ground cover, the initial deficit of moisture in the root zone, considered as 40% of SRmáx, propagation velocity in the channel, calculated from the time of concentration and storage exponential transmissivity and effective soil, both obtained in literature. 20 events were chosen during the July 19th, 2009 to December 28th, 2011, which were randomly selected for calibration 6 events and 14 events for model validation. The simulated events in the calibration process tended to underestimate the Qmáx and LES averaged 71% and 51%, respectively, at the end of the process was calculated average of the input parameters and values as a criterion of events that showed positive values efficiency to be used in the validation process. After the 14 events designed to simulate the process of validating the model, we observed a tendency of the model to simulate four types of hydrographs, which are events in which the values of Qmáx and LES were underestimated on average by 50%, events that showing simulations with two peaks Qmáx, where the first was underestimated and the second peak was overestimated, events that showed the best efficiency with a well defined peak, and events that showed the worst performance. In summary the model underestimated the Qmáx in 71% of events and the LES in 51% of events. It is worth mentioning events 6, 10 and 14 when it showed an accuracy of 0.70, and events 9 and 11, as for not their amplitudes of rainfall intensity encompassed by the calibration procedure gave the poorest results among all events Validation analyzed. Despite the low efficiency in TOPMODEL present several simulations of flow hydrographs of runoff, the model is promising in modeling of hydrographs, once that the values of flow analyzed in MCJ are very small
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Stewart, Adam Gillis. "Hydrological modeling to support simulation of an ozone exceedance episode over Texas." Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/19075.
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Mattern, David Ellis 1957. "Hydrologic simulation of pinyon-juniper woodlands in Arizona." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277116.
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A physically-based, user friendly, hydrologic computer simulation model was developed for pinyon-juniper woodland watersheds. The data requirements are minimum, requiring vegetation conditions, basic soil survey information, and daily values for precipitation and temperature. The model predicts runoff from cleared and uncleared watersheds by simulating hydrologic processes on a daily basis. The model was tested with data from small pinyon-juniper watersheds in central Arizona. A crack-forming vertisol was the dominant soil type, and a special feature for addressing its effects on runoff was included. No significant difference between predicted and observed annual runoff was found at the ninety-five percent confidence level.
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Tamanna, Marzia. "Dynamically Downscaled NARCCAP Climate Model Simulations| An Evaluation Analysis over Louisiana." Thesis, University of Louisiana at Lafayette, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1594520.
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In order to make informed decisions in response to future climate change, researchers, policy-makers, and the public need climate projections at the scale of few kilometers, rather than the scales provided by Global Climate Models. The North American Regional Climate Change Assessment Program (NARCCAP) is such a recent effort that addresses this necessity. As the climate models contain various levels of uncertainty, it is essential to evaluate the performance of such models and their representativeness of regional climate characteristics. When assessing climate change impacts, precipitation is a crucial variable, due to its direct influence on many aspects of our natural-human ecosystems such as freshwater resources, agriculture and energy production, and health and infrastructure. The current study performs an evaluation analysis of precipitation simulations produced by a set of dynamically downscaled climate models provided by the NARCCAP program. The Assessment analysis is implemented for a period that covers 20 to 30 years (1970-1999), depending on joint availability of both the observational and the NARCCAP datasets. In addition to direct comparison versus observations, the hindcast NARCCAP simulations are used within a hydrologic modeling analysis for a regional ecosystem in coastal Louisiana (Chenier Plain). The study concludes the NARCCAP simulations have systematic biases in representing average precipitation amounts, but are successful at capturing some of the characteristics on spatial and temporal variability. The study also reveals the effect of precipitation on salinity concentrations in the Chenier Plain as a result of using different precipitation forcing fields. In the future, special efforts should be made to reduce biases in the NARCCAP simulations, which can then lead to a better presentation of regional climate scenarios for use by decision makers and resource managers.
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Fassnacht, Steven Richard. "Distributed snowpack simulation using weather radar with an hydrologic-land surface scheme model." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ51194.pdf.
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Bogati, Rabin 1954. "A simulation model to assess the hydrologic perforance of the Tinau watershed, Nepal." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/191891.
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A physical event-based computer methodology is presented for evaluating the hydrologic performance of the Tinau watershed in Nepal. A stochastic model of the seasonal precipitation was developed and used to generate long-term daily synthetic rainfall data. Storm systems in the monsoon months of JUNE through SEPTEMBER are treated as frontal systems, and the storms of the remaining months of the year as independent thunderstorm events. A fitted-parameter conceptual model, called a generalized streamflow simulation system (GSSS), is used to simulate long baseflow recessions. The GSSS model transforms the synthetic rainfall data into daily streamflow using a soil moisture accounting process in a physically consistent manner. The computer output from the model consists of statistics and cumulative density functions for monthly, seasonal and annual discharges, maximum daily high and low flows, and consecutive days of low baseflow. The model output can be used by decision makers to meet the objectives of proper land use and development.
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Bosley, II Eugene Kern. "Hydrologic Evaluation of Low Impact Development Using a Continuous, Spatially-Distributed Model." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/34263.
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Low Impact Development (LID) is gaining popularity as a solution to erosion, flooding, and water quality problems that stormwater ponds partially address. LID analysis takes a spatially lumped approach, based on maintaining the predevelopment Curve Number and time of concentration, precluding consideration of the spatial distribution of impervious areas and Integrated Management Practices (IMPâ s), runoff-runon processes, and the effects of land grading. Success is thus dependent on the accuracy of the assumption of watershed uniformity, applied to both land cover distribution and flow path length.
Considering the cost of long-term paired watershed monitoring, continuous, spatially-distributed hydrologic modeling was judged a better method to compare the response of LID, forest, and conventional development. Review of available models revealed EPA-SWMM 4.4H as the most applicable to the task. A 4.3-acre subwatershed of a local subdivision was adapted to LID using impervious surface disconnection, forest retention, and IMPâ s. SWMM was applied to the LID development at a fine spatial scale, yielding an 80-element SWMM model. The LID model was modified to reflect conventional development, with gutters, storm sewer, and detention. A predevelopment forest model was also developed. Two parameter sets were used, representing a range of assumptions characterized as favorable or unfavorable toward a particular development form. Modeled scenarios included favorable and unfavorable versions of Forest, LID, uncontrolled Conventional Development, and Conventional Development with Stormwater Management. SWMM was run in continuous mode using local rainfall data, and event mode using NRCS design storms. Runoff volumes, peak flows, and flow duration curves were compared.
Master of Science
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Thoms, R. Brad. "Simulating fully coupled overland and variably saturated subsurface flow using MODFLOW /." Full text open access at:, 2003. http://content.ohsu.edu/u?/etd,16.
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Sorribas, Mino Viana. "Simulação da dinâmica de carbono em bacias hidrográficas." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/49161.
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Na maior parte dos ecossistemas aquáticos a respiração excede a produção primária bruta autóctone, acarretando uma produção líquida de ecossistema negativa. Estudos recentes atribuem essa condição a processos de degradação de matéria orgânica alóctone, portanto o ciclo do carbono em corpos de água interiores deve estar pareado com o aporte de carbono orgânico originado na bacia hidrográfica. Este trabalho contribui para a melhor compreensão dos processos atuantes no ciclo de carbono em bacias hidrográficas, por meio de monitoramento de dados de campo, desenvolvimento e aplicação de modelagem matemática e simulação numérica. O estudo foi realizado utilizando dados de monitoramento na bacia hidrográfica do Rio Ijuí localizada no planalto meridional gaúcho. A exportação fluvial de carbono orgânico e inorgânico foi estimada a partir de dados de vazão e concentração. Um modelo baseado em processos para simulação da dinâmica de carbono, MGB-IPH-C, foi desenvolvido e acoplado ao modelo hidrológico MGB-IPH. O modelo hidrológico foi ajustado em diversos pontos de controle na bacia hidrográfica do Ijuí obtendo-se bons resultados, principalmente para as bacias de maior porte (>1000 km2). O modelo de carbono foi avaliado qualitativamente considerando a representação de processos conceituais e, quantitativamente, pela comparação das concentrações e fluxos simulados em relação aos obtidos pelos dados do monitoramento. Não foi possível identificar associações diretas entre as concentrações de carbono inorgânico ou orgânico e vazão, com base nos dados medidos em campo. As cargas médias de carbono nas bacias estudadas apresentaram valores abaixo da média global, na ordem de 25-40 kg.ha-1.ano-1 e 8-10 kg.ha-1.ano-1, para as frações inorgânica e orgânica, respectivamente. O MGB-IPH-C representou processos conceituais esperados, em especial, a acumulação no solo e o efeito da lavagem das águas sobre a concentração dos rios. Foi possível obter bons ajustes em escala anual para as cargas e concentrações médias de carbono na bacia de estudo. A simulação da dinâmica de carbono em ecossistemas aquáticos em pareamento com a bacia hidrográfica utilizando modelos conceituais determinísticos contribui para o entendimento dos processos operantes nesses sistemas e deve ser complementada por meio de análise de dados de monitoramento, em freqüência adequada à escala, com métodos empíricos.In most aquatic ecosystems respiration exceeds autochtonous gross primary production leading to a negative net ecosystem production. Recent studies attributes this condition to allochtonous organic matter degradation processes, so the inland water carbon cycle should be linked to the input of organic carbon from the catchment. This work contributes to a better comprehension of processes operating in the carbon cycle in river basins, throughout development and application of mathematical modeling and numerical simulation. The study was conducted using data of the Ijuí river watershed, located in the Planalto Meridional Gaúcho. Fluvial exports of organic and inorganic carbon were estimated from data measured in field. A process-based model for carbon dynamics simulation, MGB-IPH-C, was developed and coupled to the hydrological model MGB-IPH. The hydrological model was calibrated to various control points in the Ijui river basin with good results, especially in larger subwatersheds (>1000 km2). The carbon model was evaluated considering the representation of carbon dynamics conceptual processes and by comparison of observed carbon concentrations and export rates obtained by simulation and monitoring data. The estimates of annual export of carbon in the study area were below the global average, in magnitude of 25-40 kg/ha.yr and 8-10 kg/ha.yr for inorganic and organic carbon, respectively. The proposed carbon model, MGB-IPH-C, was able to simulate expected conceptual processes, in particular, the build-up on soil and the effect of wash-off on carbon concentration in river reaches. It was possible to obtain good fits for annual average carbon fluvial export rates and concentrations. The simulation of carbon dynamics in inland waters coupled with the watershed using conceptual deterministic models contributes to the understanding of processes operating on these systems and may be complemented throughout analysis of field data, at frequency appropriated to the scale, with empirical methods.
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Zhang, Xiaohui. "Integration of a stochastic space-time rainfall model and distributed hydrologic simulation with GIS." Diss., The University of Arizona, 1997. http://hdl.handle.net/10150/282409.
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This research presents an integration of a stochastic space-time rainfall model and distributed hydrologic simulation with GIS. The integrated simulation system consists of three subsystems: a stochastic space-time rainfall model, a geographical information system (GIS), and a distributed physically-based hydrologic model. The developed stochastic space-time rainfall model is capable of estimating the storm movement and simulating a random rainfall field over a study area, based on the measurement from three raingauges. An optimization-based lag-k correlation method was developed to estimate the storm movement, and a stochastic model was developed to simulate the rainfall field. A GIS tool, ARC/INFO, was integrated into this simulation system. GIS has been applied to automatically extract the spatially distributed parameters for hydrologic modeling. Digital elevation modeling techniques were used to process a high resolution digital map. A distributed physically-based hydrologic model, operated in HEC-1, simulated the stochastic, distributed, interrelated hydrological processes. The Green-Ampt equation is used for modeling the infiltration process, kinematic wave approximation for infiltration-excess overland flow, and the diffusion wave model for the unsteady channel flow. Two small nested experimental watersheds in southern Arizona were chosen as the study area where three raingauges are located. Using five recorded storm events, a series of simulations were performed under a variety of conditions. The simulation results show the model performs very well, by comparing the simulated runoff peak flow and runoff depth with the measured ones, and evaluated by the model efficiency. Both model structure and model parameter uncertainties were investigated in the sensitivity analysis. The statistical tests for the simulation results show that it is important to model stochastic rainfall with storm movement, which caused a significant change in runoff peak flow and runoff depth from that where the input is only one gage data. The sensitivity of runoff to roughness factor N and hydraulic conductivity Ks were intensively investigated. The research demonstrated this integrated system presents an improved simulation environment for the distributed hydrology.
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Kautz, Mark Anderson, and Mark Anderson Kautz. "Hydrologic Model Parameterization Using Dynamic Landsat-Based Foliar Cover Estimates for Runoff Simulation on a Semiarid Grassland Watershed." Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/622850.
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Changes in watershed vegetative cover from natural and anthropogenic causes including, climatic fluctuations, wildfires and land management practices, can result in increased surface water runoff and erosion. Hydrologic models play an important role in the decision support process for managing these landscape alterations. However, model parameterization requires quantified measures of watershed biophysical condition to generate accurate results. These inputs are often obtained from nationally available land cover data sets that are static in terms of vegetation condition and phenology. Obtaining vegetative data for model input of sufficient spatiotemporal resolution for long-term, watershed-scale change analysis has been a challenge. The purpose of this research was to assess the implications of parameterizing the event-based, Rangeland Hydrology and Erosion Model (RHEM) with dynamic, remotely sensed foliar cover data. The study was conducted on a small, instrumented, grassland watershed within the Walnut Gulch Experimental Watershed surrounding Tombstone, Arizona. A time series of foliar cover rasters was produced by calibrating Landsat-based Soil Adjusted Total Vegetation Index (SATVI) scenes with field measurements. Estimates of basal and litter cover were calculated using allometric relationships derived from ground-based transect data. The model was parameterized using these remotely sensed inputs for all recorded runoff events from 1996-2014. Model performance was improved using the remotely sensed foliar cover compared to using an a priori value based on static national land cover classes. Significant (p<0.05) correlation was shown for the linear relationships between foliar cover and SATVI, foliar cover and basal cover, and foliar cover and litter cover. The integration of Landsat-based vegetative data into RHEM shows potential for modelling on a broadened spatiotemporal scale, allowing for improved landscape characterization and the ability to track watershed response to long-term vegetation changes.
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Berg, Karin. "Simulations of groundwater levels and soil water content : Development of a conceptual hydrological model with a continous soil profile." Thesis, Linköping University, Department of Thematic Studies, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1910.
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Transport of chemical substances through a catchment depend to a large extent on the water content of the soil through which they are transported. When the groundwater level rise and fall, redox conditions change in the soil and the transport of substances is affected.
The aim of this study is to develop a hydrological model which is able to simulate soil water content at different depths and groundwater level in a soil profile. A new type of conceptual model is developed, which uses a continous represenation of the soil and soil water from the soil surface down to the bedrock. The model is intended to be applied on small catchments at a later stage.
The results show that the simulation of groundwater levels was greatly improved compared to previous results. Simulation of soil water content at selected depths is not yet satisfactory. The runoff simulation was accurate at one of the sites but did not work as well at the other. At one of the sites it was also possible to combine good simulations of runoff and groundwater levels but at the other it was only possible to obtain acceptable simulations of either runoff or groundwater.
It is suggested that model performance could be improved by letting the porosity decrease and the soil water content increase non-linearly with depth. Calculations of evaporation from soil and runoff also need to be modified.
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Zarekarizi, Mahkameh. "Ensemble Data Assimilation for Flood Forecasting in Operational Settings: from Noah-MP to WRF-Hydro and the National Water Model." PDXScholar, 2018. https://pdxscholar.library.pdx.edu/open_access_etds/4651.
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The National Water Center (NWC) started using the National Water Model (NWM) in 2016. The NWM delivers state-of-the-science hydrologic forecasts in the nation. The NWM aims at operationally forecasting streamflow in more than 2,000,000 river reaches while currently river forecasts are issued for 4,000. The NWM is a specific configuration of the community WRF-Hydro Land Surface Model (LSM) which has recently been introduced to the hydrologic community. The WRF-Hydro model, itself, uses another newly-developed LSM called Noah-MP as the core hydrologic model. In WRF-Hydro, Noah-MP results (such as soil moisture and runoff) are passed to routing modules. Riverine water level and discharge, among other variables, are outputted by WRF-Hydro. The NWM, WRF-Hydro, and Noah-MP have recently been developed and more research for operational accuracy is required on these models. The overarching goal in this dissertation is improving the ability of these three models in simulating and forecasting hydrological variables such as streamflow and soil moisture. Therefore, data assimilation (DA) is implemented on these models throughout this dissertation. State-of-the art DA is a procedure to integrate observations obtained from in situ gages or remotely sensed products with model output in order to improve the model forecast.
In the first chapter, remotely sensed satellite soil moisture data are assimilated into the Noah-MP model in order to improve the model simulations. The performances of two DA techniques are evaluated and compared in this chapter. To tackle the computational burden of DA, Massage Passing Interface protocols are used to augment the computational power. Successful implementation of this algorithm is demonstrated to simulate soil moisture during the Colorado flood of 2013. In the second chapter, the focus is on the WRF-Hydro model. Similarly, the ability of DA techniques in improving the performance of WRF-Hydro in simulating soil moisture and streamflow is investigated.
The results of chapter 2 show that the assimilation of soil moisture can significantly improve the performance of WRF-Hydro. The improvement can reach 58% depending on the study location. Also, assimilation of USGS streamflow observations can improve the performance up to 25%. It was also observed that soil moisture assimilation does not affect streamflow. Similarly, streamflow assimilation does not improve soil moisture. Therefore, joint assimilation of soil moisture and streamflow using multivariate DA is suggested.
Finally, in chapter 3, the uncertainties associated with flood forecasting are studied. Currently, the only uncertainty source that is taken into account is the meteorological forcings uncertainty. However, the results of the third chapter show that the initial condition uncertainty associated with the land state at the time of forecast is an important factor that has been overlooked in practice. The initial condition uncertainty is quantified using the DA. USGS streamflow observations are assimilated into the WRF-Hydro model for the past ten days before the forecasting date.
The results show that short-range forecasts are significantly sensitive to the initial condition and its associated uncertainty. It is shown that quantification of this uncertainty can improve the forecasts by approximately 80%. The findings of this dissertation highlight the importance of DA to extract the information content from the observations and then incorporate this information into the land surface models. The findings could be beneficial for flood forecasting in research and operation.
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Oliveira, Cristiano de Pádua Milagres. "Plataforma de análise e simulação hidrológica - PLASH." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/3/3147/tde-15052014-162931/.
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A modelagem matemática da hidrologia de bacias hidrográficas é largamente utilizada em estudos de diversos tipos de problemas encontrados na engenharia hidráulica e de recursos hídricos. Nestes últimos 150 anos, muitos pesquisadores realizaram observações e experimentos sobre a natureza do ciclo hidrológico para que pudessem entender e equacionar seu comportamento. Diversos modelos diferentes surgiram baseando-se em equacionamentos físicos e empíricos, sendo que muitos destes modelos clássicos são utilizados até hoje. Para se ter uma visão mais abrangente do tema, uma revisão do estado da arte é apresentada, com uma perspectiva histórica destes modelos e seus criadores, assim como uma classificação fundamentada em suas características. Também são examinados alguns dos sistemas computacionais para modelagem hidrológica de bacias hidrográficas mais utilizados atualmente. São discutidas as hipóteses de uma simplificação do ciclo hidrológico para eventos intensos utilizados em projetos. Cada componente do ciclo hidrológico simplificado é modelado utilizando um dos diferentes modelos hidrológicos propostos, com graus de complexidade distintos. Para cada um destes modelos é realizada uma análise de sensibilidades dos seus parâmetros. Baseado nos avanços tecnológicos mais recentes na ciência da computação foi desenvolvido, em paralelo a esta pesquisa, uma ferramenta computacional que compila todos os conceitos aqui apresentados e tem distribuição acadêmica livre.The mathematical modeling of the watershed hydrology is widely used in studies of several problems related to hydraulic and water resources engineering. On these last 150 years, many researchers accomplished observations and experiments on the nature of the hydrologic cycle in order to understand and equates its behavior. Several different models appeared basing on physical and empiric equating, and many of these classic models are being used until today. To get a more comprehensive view on the theme, a state of the art revision is presented, with an historical perspective about these models and its creators, such as a classification based on its characteristics are presented. Also some computational systems of hydrologic modeling of watershed are also examined more used now. The hypotheses of a simplification of the hydrologic cycle are discussed for intense events used in projects. Each component of the simplified hydrologic cycle is modeled using one of the different hydrologic models proposed, with distinct grades of complexity. For each one of these models a sensibility analysis of their parameter is performed. Based on the more recent technological progresses in the computational science was developed, parallel to this research, a computational tool that compiles all the concepts here presented and has free academic distribution.
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Bahaya, Bernard. "Quantifying the benefits of hydrologic simulation and the implementation of active control for optimizing performance of green stormwater infrastructure." University of Toledo / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1571315862174829.
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Jeton, Anne Elizabeth 1956. "Vegetation management and water yield in a southwestern ponderosa pine watershed: An evaluation of three hydrologic simulation models." Thesis, The University of Arizona, 1990. http://hdl.handle.net/10150/277298.
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Three hydrologic simulation models of different resolutions were evaluated to determine model response to predicting runoff under changing vegetation cover. Two empirically-based regression models (Baker-Kovner Streamflow Regression Model and ECOSIM) and one multiple component water balance model (Yield) were modified, using FORTRAN 77 and calibrated on a southwestern ponderosa pine ecosystem. Statistical analysis indicate no significant difference between the Baker-Kovner and Yield models, while ECOSIM consistently under predicts by as much as 50 percent from the observed runoff. This is mainly attributed to a sensitivity to the insolation factor. Yield is the best predictor for moderate and high flows, to within 10 and 20 percent respectively. Of the four watershed treatments, the light overstory thinning on Watershed 8 yielded the best response for all three models. This is in contrast to the strip-cut treatment on Watershed 14 which consistently over-predicted, in large part due an inaccurate estimation of snowpack evaporation on the exposed, south-facing strip-cuts. Runoff responses are highly influenced by the precipitation regime, soil and topographic characteristics of a watershed as well as by a reduction in evapotranspiration losses from changes in vegetation cover.
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Poméon, Thomas [Verfasser]. "Evaluating the Contribution of Remote Sensing Data Products for Regional Simulations of Hydrological Processes in West Africa using a Multi-Model Ensemble / Thomas Poméon." Bonn : Universitäts- und Landesbibliothek Bonn, 2019. http://d-nb.info/1188731483/34.
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Imam, Bisher 1960. "Evaluation of disaggregation model in arid land stream flow generation." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277033.
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A Disaggregation model was tested for arid land stream flow generating. The test was performed on data from Black River, near Fort Apache, Arizona. The model was tested in terms of preserving the relevant historical statistics on both monthly and daily levels, the monthly time series were disaggregated to a random observation of their daily components and the daily components were then reaggregated to yield monthly values. A computer model (DSGN) was developed to perform the model implementation. The model was written and executed on the Macintosh plus personal computer Data from two months were studied; the October data represented the low flow season, while the April data represented the high flow season. Twenty five years of data for each month was used. The generated data for the two months was compared with the historical data.
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Perez, Gonzalez Maria Fernanda. "Use Of Cuencas hydrological model in simulating the effects of land use change on the 2008 flooding event in the Turkey River Watershed." Thesis, University of Iowa, 2011. https://ir.uiowa.edu/etd/1168.
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East Iowa experienced large flooding during June of 2008. This study used Cuencas hydrological model to simulate the discharges of June 2008 at Eldorado and Elkader, in the Turkey River Watershed, in North East Iowa. The results of this study were used to test the performance of Cuencas modeling this flood event and to explore the role of land cover change in the floods of 2008 at Elkader, Iowa.
Cuencas was found to be a suitable tool to predict this event, that requires relatively low resources. The total time to run each simulation was around two hours which is reasonable for such large watershed (900 mi2), but a computer cluster was needed to run these simulations.
The results from this study suggest that the role of land cover change from pre-settlement to current conditions was significant when using the rainfall conditions of 2008. The discharges simulated at Elkader, Iowa were almost twice as large when using the 2001 land cover, than when using the land cover found during 1832-1859, recorded during the General Land Office (GLO) survey. These results need to be taken only as preliminary results, since there is no data to validate the model at the time of the GLO survey, and since it is the first time that Cuencas is used to model the effects of land cover in Iowa's hydrology. However, the potential large reduction on discharge of the pre-settlement land cover is an incentive to investigate this issue further and continue developing Cuencas to capture the effects of less drastic land cover changes.
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DIXIT, VRUSHALI. "ASSESSING THE APPLICABILITY OF LINKING A HYDROLOGIC MODEL WITH GIS SIMULATION TO PLAN FOR STORM WATER RUNOFF CONTROL IN THE MILL CREEK WATERSHED OF CINCINNATI." University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1025639157.
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Cesarini, Chiara. "Analysis of the importance of the snow module and of the simulation of extreme streamflows in the presence of a dam using the "GR" hydrological models." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/17709/.
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The aim of my thesis is to study different aspects of hydrological modelling.
The study have been performed with the “GR” hydrological models developed by the hydrological research team of IRSTEA, institute where I completed my thesis work.
Three basins with different locations and hydro-climates have been analysed.
Before running the “GR” models, the hydro-climatic features of the watersheds have been analysed in order to distinguish their nival or pluvial character.
Secondly a set of simulations has been performed in order to understand how the different calibrations could affect the simulated discharges: in particular, the components of the Kling-Gupta efficiency goodness-of-fit criteria provided information on the ability to reproduce different aspects and parts of a simulated hydrograph, while the parameters of the models have been studied to understand their sensitivity to the different calibration inputs.
Furthermore the role of the inclusion of a snow accounting model has been analysed comparing the streamflows simulation with and without the “CemaNeige” module: the snow melting resulted to be an essential process for the nival basins and neglecting it resulted in poor simulations.
Moreover, to demonstrate that the simulation of parts of the hydrograph can be improved through objective functions based on transformations of the output, some tests have been performed and the results showed that high flows were well reproduced without transformation, while calibrating on inverse and square root transformation allowed the best reproduction of low flows and of a wider range of discharges respectively.
The last subject analysed was the effect that the presence of a dam can have on the catchment behaviour: few years of observed discharges and of reservoir water levels measured in a fourth basin have been compared. The analysis confirmed that the dam played a role of mitigation of the extreme discharges, reducing the high flows and enhancing the low ones.
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Caldeira, Tamara Leitzke. "Aprimoramento computacional do modelo Lavras Simulation of Hydrology (LASH) : aplicação em duas bacias do Rio Grande do Sul." Universidade Federal de Pelotas, 2016. http://repositorio.ufpel.edu.br/handle/ri/2833.
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A modelagem hidrológica em bacias hidrográficas consiste numa das principais e mais modernas ferramentas para gestão de recursos hídricos e dimensionamentos hidrológicos, no entanto, muitos modelos demandam um grande número de informações temporais e espaciais, o que muitas vezes impede que sejam aplicados, principalmente em países em desenvolvimento, como é o caso do Brasil, onde é mais observado o monitoramento de bacias de grande porte. Frente a este fato, em 2008 uma equipe de pesquisadores da Universidade Federal de Lavras, em parceria com a Universidade de Purdue (EUA), deram início ao desenvolvimento de um modelo hidrológico conceitual voltado à bacias com limitações na base de dados; em 2008 surgia a primeira versão deste modelo e, em 2009, a segunda, quando passaria a ser chamado de Lavras Simulation of Hydrology (LASH). O modelo LASH passou por aprimoramentos computacionais entre o desenvolvimento da primeira e da segunda versão, contudo, não apresentava-se “amigável” para suprir a demanda por parte de profissionais fora do ambiente acadêmico. Foi então que surgiu a ideia de desenvolver sua terceira versão, contando agora também com a parceria da Universidade Federal de Pelotas. O objetivo deste trabalho foi desenvolver e apresentar a terceira versão do modelo LASH, contemplando módulos auxiliares, inúmeros aprimoramentos computacionais e a adaptação da rotina hidrológica e de calibração automática para modelagem com discretização espacial por sub-bacias hidrográficas, bem como avaliar a aplicabilidade desta versão à duas bacias hidrográficas localizadas no sul do Rio Grande do Sul, sob duas estratégias distintas de calibração. Os resultados obtidos apontam para um enorme avanço computacional: i) o módulo para processamento da base de dados temporal (SYHDA) tomou grandes proporções durante seu desenvolvimento, ao ponto de ter sido registrado junto ao Instituto Nacional de Propriedade Industrial (INPI) e vir sendo empregado de forma isolada ao modelo, como uma importante ferramenta de análises hidrológicas; ii) o módulo de processamento da base dados espaciais se mostrou bastante eficiente e, neste momento, encontra-se sob aguardo de deferimento de registro junto ao INPI iii) os módulos de banco de dados, integração e calibração automática se mostraram indispensáveis frente às funcionalidades que lhes foram atribuídas; e iv) o tempo de processamento foi bastante inferior quando comparado à segunda versão. Do ponto de vista hidrológico, a análise do desempenho da terceira versão do LASH frente à calibração e validação para as bacias analisadas indica que o modelo foi capaz de capturar o comportamento geral das vazões observadas, no entanto, a representatividade espacial dos processos hidrológicos é menor quando comparada à segunda versão. No que tange à calibração, as estratégias empregadas apresentaram resultados distintos, assim como as funções objetivo, tendo sido o modelo mais eficiente quando todos parâmetros foram calibrados de forma concentrada. Esta constatação dá indícios de que a estrutura do módulo de calibração automático precisa ser melhor avaliada e de que deve-se analisar a possibilidade de empregar métodos de calibração multiobjetivo, os quais são mais aconselháveis, segundo a literatura, quando objetiva-se a utilização do modelo em ambientes não acadêmicos.
Hydrological watershed modeling is considered one of the main and most modern tools for water resources management and hydrological designs; however, many models require a large amount of temporal and spatial information. This commonly makes it difficult their application, especially in Brazil and in other developing countries, where hydrological monitoring has been predominantly observed for large watersheds. In 2008, a research team from Federal University of Lavras in collaboration with Purdue University (USA) began the development of a conceptual hydrological model intended for data-scarce watersheds. The researchers finished the first version of such model in 2008 and, its second version in 2009, which was known as Lavras Simulation of Hydrology (LASH). The second version of LASH model had many computational refinements in relation to its first version; nevertheless, it does not have a friendly integrated development environment (IDE) to fulfil the needs of non-academic professionals. Then, the research team decided to develop its third version, having collaboration with Federal University of Pelotas. The objectives of this study were to: i) develop and present the third version of the LASH model, addressing auxiliary modules, countless computational enhancements and adaptation of hydrological and automatic calibration routines for modeling with spatial discretization of subwatersheds; and ii) evaluate the applicability of this version to two watersheds situated in the southern Rio Grande do Sul State, considering two calibration schemes. The results found in this study indicated a considerable computational upgrade: i) the module designed for processing of temporal data bases (SYHDA) has been frequently used in many applications as an independent software since its development, such that it was protected by copyright (Instituto de Propriedade Industrial – INPI); ii) the module for processing of spatial data bases was considered efficient and also protected by copyright (INPI); iii) the modules of database, integration and automatic calibration were indispensable considering their designed functionalities; and iv) the time of processing was undoubtedly less than that spent by the second version. Under the hydrological point of view, the performance analysis of the third version of LASH, with respect to calibration and validation of the studied watersheds, indicated that the model was able to capture the overall behavior of the observed hydrograph; however, it should be mentioned that the spatial representativeness of the hydrological processes is inferior when compared to that existing in the second version. Relative to calibration, the used schemes and objective functions presented somewhat contrasting results; the most efficient scheme was that in which all the calibration parameters were lumped. This finding suggests that the framework of the automatic calibration module needs to be better evaluated and that there might be the necessity to implement multi-objective calibration algorithms, which have drawn attention in scientific community, when the goal is the model application for non-academic purposes.
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Ferreira, Lucia. "Simulação hidrologica utilizando o modelo TOPMODEL em bacias rurais, estudo de caso na bacia do Ribeirão dos Marins ¿ seção Monjolinho - SP." [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257541.
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Orientador: Jose Teixeira FilhoTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola
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Doutorado
Agua e Solo
Doutor em Engenharia Agrícola
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Hamududu, Byman Hikanyona. "Impacts of Climate Change on Water Resources and Hydropower Systems : in central and southern Africa." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for vann- og miljøteknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-19929.
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Climate change is altering hydrological processes with varying degrees in various regions of the world. This research work investigates the possible impacts of climate change on water resource and Hydropower production potential in central and southern Africa. The Congo, Zambezi and Kwanza, Shire, Kafue and Kabompo basins that lie in central and southern Africa are used as case studies. The review of climate change impact studies shows that there are few studies on impacts of climate change on hydropower production. Most of these studies were carried out in Europe and north America and very few in Asia, south America and Africa. The few studies indicate that southern Africa would experience reduction in precipitation and runoff, consequently reductions in hydropower production. There are no standard methods of assessing the resulting impacts. Two approaches were used to assess the impacts of climate change on water resources and hydropower. One approach is lumping changes on country or regional level and use the mean climate changes on mean annual flows as the basis for regional changes in hydropower production. This is done to get an overall picture of the changes on global and regional level. The second approach is a detailed assessment process in which downscaling, hydrological modelling and hydropower simulations are carried out. The possible future climate scenarios for the region of central and southern Africa depicted that some areas where precipitation are likely to have increases while other, precipitation will reduce. The region northern Zambia and southern Congo showed increases while the northern Congo basin showed reductions. Further south in southern African region, there is a tendency of decreases in precipitation. To the west, in Angola, inland showed increases while towards the coast highlighted some decreases in precipitation. On a global scale, hydropower is likely to experience slight changes (0.08%) due to climate change by 2050. Africa is projected for a slight decrease (0.05%), Asia with an increase of 0.27%, Europe a reduction up to 0.16% while America is projected to have an increase of 0.05%. In the eastern African region, it was shown that hydropower production is likely to increase by 0.59%, the central with 0.22% and the western with a 0.03%. The southern, and northern African regions were projected to have reductions of 0.83% and 0.48% respectively. The basins with increases in flow projections have a slight increase on hydropower production but not proportional to the increase in precipitation. The basins with decreases had even high change as the reduction was further increased by evaporation losses. The hydropower production potential of most of southern African basins is likely to decrease in the future due to the impact of climate change while the central African region shows an increasing trend. The hydropower system in these regions will be affected consequently. The hydropower production changes will vary from basin to basin in these regions. The Zambezi, Kafue and Shire river basins have negative changes while the Congo, Kwanza and Kabompo river basins have positive changes. The hydropower production potential in the Zambezi basin decreases by 9 - 34%. The hydropower production potential in the Kafue basin decreases by 8 - 34% and the Shire basin decreases by 7 - 14 %. The southern region will become drier with shorter rainy seasons. The central region will become wetter with increased runoff. The hydropower production potential in the Congo basin reduces slightly and then increases by 4% by the end of the century. The hydropower production potential in the Kwanza basin decreases by 3% and then increases by 10% towards the end of the century and the Kabompo basin production increases by 6 - 18%. It can be concluded that in the central African region hydropower production will, in general, increase while the southern African region, hydropower production will decrease. In summary, the analysis has shown that the southern African region is expected to experience decreases in rainfall and increases in temperature. This will result in reduced runoff. However the northern part of southern Africa is expected to remain relatively the same with slight increase, moving northwards towards the central African region where mainly increases have been registered. The southern African region is likely to experience reductions up to 5 - 20% while the central African region is likely to experience an increase in runoff in the range of 1 - 5%. Lack of data was observed as a critical limiting factor in modelling in the central and southern Africa region. The designs, plans and operations based on poor hydrological data severely compromise performance and decrease efficiency of systems. Climate change is expected to change these risks. The normal extrapolations of historical data will be less reliable as the past will become an increasingly poor predictor of the future. Better (observed) data is recommended in future assessments and if not better tools and methods for data collection/ should be used. Future designs, plans and operations should include and aspect of climate change, if the region is to benefit from the climate change impacts.
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Amaral, José Americo Bordini do. "Estudo de várzea da planície de inundação da bacia do Ribeirão do Feijão - SP." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-01122016-120047/.
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A partir de setembro de 1999 até novembro de 2000 estudou-se a várzea da margem direita da planície de inundação do Ribeirão do Feijão, com objetivo de verificação da várzea funcionando como filtro natural na contenção de matéria orgânica utilizando-se para esse estudo, um modelo de simulação desenvolvido com o software Stella. Foram coletados dados climatológicos oriundos de estação climatológica automática (temperatura do ar, umidade relativa, precipitação, radiação solar, velocidade e direção do vento e pressão barométrica), em piezômetros instalados na várzea (em número de 9) e coleta de amostras de água no rio, dados limnológicos: físicos (temperatura da água, turbidez, oxigênio dissolvido, condutividade e profundidade); químicos (fósforo total, fósforo total dissolvido, silicato, nitrogênio total, nitrato, nitrito e amônia), além de dados obtidos pelo estudo da literatura e trabalhos próximos da área de estudo já publicados. A partir do estudo da inter-relação dos processos existentes na várzea de inundação do Ribeirão do Feijão, elaborou-se modelo de simulação. As conclusões que se obtiveram indicam bom comportamento do modelo de simulação e, também, que estudos em escala de tempo mais reduzida sejam utilizados em trabalhos futuros para estudos de várzeas. Outra conclusão refere-se ao funcionamento da várzea como filtro natural, onde houve armazenamento de carbono (matéria orgânica). Constatou-se grande amplitude da variação diária da altura da lâmina d\'água devido à evapotranspiração. Recomenda-se a preservação desse rio porque 40% da água de superfície que abastece a cidade de São Carlos é oriunda desse manancial.From September 1999 up to November 2000 a wetland of the right margin of Feijão river floodplain was studied with the objective to verify its activity as an natural filter to retain organic matter making use of a simulation model constructed with the help of the Stella software. Were collected climatological data from an automatic climatological station (air temperature, air moisture, rain, solar radiation, speed and wind direction and atmospheric pressure), from piezometers installed within the wetland (number of 9) and samples collected of river water, limnological data: physical data (water temperature, turbidity, dissolved oxygen, conductivity and depth); chemical data (total phosphorus, total dissolved phosphorus, silicate, total nitrogen, nitrate, nitrite and ammonium), moreover data obtained from literature and papers published of sites near the study area. From the interrelationship of processes occurring within the Feijão river floodplain wetland was constructed the simulation model. The obtained conclusions indicate the good simulation model behavior and show that time scales should be shorter in future wetland studies. Other conclusion refer to wetland conduction as a natural filter where occurred carbon storage (organic matter). Great amplitude of water table diary variation have been verified within the wetland due to evapotranspiration. Is possible to recommend the river preservation because 40% of the surface city supply is from this site.
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Rahman, Mohammed Mizanur. "Application of SWAT for Impact Analysis of Subsurface Drainage on Streamflows in a Snow Dominated Watershed." Thesis, North Dakota State University, 2011. https://hdl.handle.net/10365/29555.
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The wet weather pattern since the early 1990's has created two problems for the people living in the Red River Valley (RRV): (1) wet field conditions for farmers and (2) more frequent major spring floods in the Red River system. Farmers in the region are increasingly adopting subsurface drainage practice to remove excess water from their fields to mitigate the first problem. However, it is not clear whether subsurface drainage will deteriorate or mitigate the spring flood situation, the second problem. The Soil and Water Assessment Tool (SWAT) model was applied to evaluate the impacts of tile drainage on the Red River's streamflows. The model was calibrated and validated against monthly streamflows at the watershed scale and against daily tile flows at the field scale. The locations and areas of the existing and potential tile drained (PTD) areas were identified using a GIS based decision tree classification method. The existing and maximum PTD areas were found to be about 0.75 and 17.40% of the basin area, respectively. At the field scale, the range of Nash-Sutcliffe efficiency (NSE) for model calibration and validation was 0.34-0.63. At the watershed scale, the model showed satisfactory performance in simulating monthly streamflows with NSE ranging from 0.69 to 0.99, except that the model under-predicted the highest spring flood peak flows in three years. The results of modeling a 100% tiled experimental field showed that about 30-40% of water yield was produced as tile flow. Surface runoff and soil water content decreased about 34% and 19%, respectively, due to tile drainage. However, the impact of subsurface drainage on evapotranspiration (ET) and water yield was mixed. ET slightly decreased in a wet year and slightly increased in a dry year, while the pattern for water yield was opposite to that of ET. The watershed-scaled modeling results showed that a tiling rate of 0.75-5.70% would not have significant effects on the monthly average streamflows in the Red River at Fargo. For the 17.40% tiling rate, the streamflow in the Red River at Fargo might increase up to 1% in April and about 2% in Fall (September to November), while decreasing up to 5% in the remaining months. This SWAT modeling study helped to better understand the impact of subsurface drainage on the water balance and streamflows in the Red River of the North basin. The findings will also help watershed managers in making decisions for the purpose of managing agricultural drainage development in the RRV and other snow dominated watersheds around the world.
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Madadgar, Shahrbanou. "Towards Improving Drought Forecasts Across Different Spatial and Temporal Scales." PDXScholar, 2014. https://pdxscholar.library.pdx.edu/open_access_etds/1516.
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Recent water scarcities across the southwestern U.S. with severe effects on the living environment inspire the development of new methodologies to achieve reliable drought forecasting in seasonal scale. Reliable forecast of hydrologic variables, in general, is a preliminary requirement for appropriate planning of water resources and developing effective allocation policies. This study aims at developing new techniques with specific probabilistic features to improve the reliability of hydrologic forecasts, particularly the drought forecasts. The drought status in the future is determined by certain hydrologic variables that are basically estimated by the hydrologic models with rather simple to complex structures. Since the predictions of hydrologic models are prone to different sources of uncertainties, there have been several techniques examined during past several years which generally attempt to combine the predictions of single (multiple) hydrologic models to generate an ensemble of hydrologic forecasts addressing the inherent uncertainties. However, the imperfect structure of hydrologic models usually lead to systematic bias of hydrologic predictions that further appears in the forecast ensembles. This study proposes a post-processing method that is applied to the raw forecast of hydrologic variables and can develop the entire distribution of forecast around the initial single-value prediction. To establish the probability density function (PDF) of the forecast, a group of multivariate distribution functions, the so-called copula functions, are incorporated in the post-processing procedure. The performance of the new post-processing technique is tested on 2500 hypothetical case studies and the streamflow forecast of Sprague River Basin in southern Oregon. Verified by some deterministic and probabilistic verification measures, the method of Quantile Mapping as a traditional post-processing technique cannot generate the qualified forecasts as comparing with the copula-based method.
The post-processing technique is then expanded to exclusively study the drought forecasts across the different spatial and temporal scales. In the proposed drought forecasting model, the drought status in the future is evaluated based on the drought status of the past seasons while the correlations between the drought variables of consecutive seasons are preserved by copula functions. The main benefit of the new forecast model is its probabilistic features in analyzing future droughts. It develops conditional probability of drought status in the forecast season and generates the PDF and cumulative distribution function (CDF) of future droughts given the past status. The conditional PDF can return the highest probable drought in the future along with an assessment of the uncertainty around that value. Using the conditional CDF for forecast season, the model can generate the maps of drought status across the basin with particular chance of occurrence in the future. In a different analysis of the conditional CDF developed for the forecast season, the chance of a particular drought in the forecast period can be approximated given the drought status of earlier seasons.
The forecast methodology developed in this study shows promising results in hydrologic forecasts and its particular probabilistic features are inspiring for future studies.
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Fensterseifer, Sandro Luciano Barreto. "INFLUÊNCIA DA RESOLUÇÃO ESPACIAL DO PIXEL NA APLICAÇÃO DO MODELO DE SIMULAÇÃO SWAT NA BACIA HIDROGRAFICA DO RIO GUAPORÉ, RS." Universidade Federal de Santa Maria, 2014. http://repositorio.ufsm.br/handle/1/3774.
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Today we know the need to preserve environmental resources, which include soils and hydrology. Estimates of water loss and soil erosion are held in different countries, using empirical or conceptual models such as SWAT (Soil and Water Assessment Tool), used to predict the impact of changes in the use and soil management, among others on soil loss and the flow of the watercourse. This model, through their routines, is able to simulate and quantify in a watershed as the dynamics of water flow and sediment occurs, the supply of information on the maps and tabular data format is required. This thesis set up two goals: first to identify the most appropriate spatial resolution for simulations, comparing the measured field data with simulated data flow and sediment yield. To this end, we analyzed how the product image affected the performance of the SWAT simulation application without being calibrated by changing their spatial resolutions of 10, 30, 50, 100 and 200 meters. After there were three analysis processes to determine which resolution gave better results of simulation, called analysis of percentage, and statistical regression, concluding that the image with 200 meter resolution showed the best results of simulation of liquid flow in the channel and without sediment transport model calibration. The second objective is to perform a simulation for basin Guapore validate and calibrate the model for liquid flow, analyzing the results for the sediment delivery with a period of 10 years of data. Performed the simulation is performed sensitivity analysis indicated that seven parameters as the most sensitive. Then ensued for calibration, effecting to change these parameters manually for flow and later to sediment production. Was used to analyze the efficiency calibration, the coefficient of efficiency. According to bibliography, this should keep values above 0.50 to be considered calibrated. For flow data were obtained for a range of average six years analyzed 0, 578 After calibration values, executed to validate the model using a seven-year period, reaching up to data an average flow of 0.68 COE. The model presented below one year with values determined by the bibliography, being satisfactory calibration and validation. As for the transport of sediment was not possible to calibrate and validate the model because the coefficient of efficiency showed high values, inferring that the main causes have been simplifying the soil loss equation uses the simulator to make some calculations, especially related to the length and steepness of slope, and basin size. Furthermore, by deducting the measured sediment data showed high variability within months of the years, making it difficult adjusting the parameters. It was concluded that the simulation process is valid for analysis and establishment of public conservation measures and preventive use of environmental resources, especially those related to the cultivation of land, and that the most appropriate spatial resolution of 200 meters for large basins. This resolution is not, perhaps, the reality for small basins, further studies should be performed.Sabe-se da necessidade de preservar os recursos ambientais, onde incluem-se os solos e a hidrologia. Estimativas da perda de água e solo por erosão são realizadas em diversos países, utilizando-se modelos empíricos ou conceituais, como o SWAT (Soil and Water Assessment Tool), utilizado para predizer o impacto das alterações no uso e no manejo do solo, entre outros, sobre a perda de solo e a vazão de curso de água. Este modelo, através de suas rotinas, tem condições de simular e quantificar em uma bacia hidrográfica como ocorre a dinâmica de fluxo de água e sedimentos, sendo necessário o abastecimento de informações no formato de mapas e dados tabulados. Nesta tese estabeleceram-se dois objetivos: o primeiro identificar qual a resolução espacial mais adequada para simulações, comparando-se dados medidos a campo com dados simulados de vazão e produção de sedimentos. Para tanto, analisou-se como o produto imagem afetou o desempenho de simulação do aplicativo SWAT sem estar calibrado, alterando-se as respectivas resoluções espaciais das imagens em 10, 30, 50, 100 e 200 metros. Após realizaram-se três processos de análise para determinar qual resolução gerou melhores resultados de simulação, denominadas de análise de percentagem, estatística e regressão, concluindo-se que a imagem com 200 metros de resolução apresentou os melhores resultados de simulação de vazão liquida no canal e transporte de sedimentos sem a calibração do modelo. O segundo objetivo é realizar uma simulação para a bacia de Guaporé validar e calibrar o modelo para vazão líquida, analisando-se os resultados para o aporte de sedimentos com um período de 10 anos de dados. Realizada a simulação, executou-se análise de sensibilidade que indicou sete parâmetros como os mais sensíveis. Seguiu-se, então, para calibração, efetivando-se a mudança destes parâmetros de forma manual para vazão e posteriormente para produção de sedimentos. Utilizou-se, para analisar a eficiência da calibração, o coeficiente de eficiência. Conforme a bibliografia, este deverá manter valores acima de 0,50 para ser considerado como calibrado. Para os dados de vazão obtiveram-se valores médios para um intervalo de seis anos, analisados de 0, 578. Após a calibração, executou-se a validação do modelo utilizando-se um período de sete anos, alcançando-se para os dados de vazão um valor médio de COE de 0,68. O modelo apresentou um ano com valores abaixo do determinado pela bibliografia, sendo satisfatória a calibração e validação. Já para o transporte de sedimentos não foi possível calibrar o modelo e validar, pois o coeficiente de eficiência apresentou valores elevados, inferindo-se que as principais causas foram a simplificação da equação de perdas de solo que o simulador utiliza para fazer alguns cálculos, principalmente relacionados ao comprimento de rampa e declividade, e o tamanho da bacia. Além disso, deduzindo-se que os dados de sedimentos medidos apresentaram uma alta variabilidade dentro dos meses nos anos, o que dificultou o ajuste dos parâmetros. Concluiu-se que o processo de simulação é valido para análises e estabelecimento de medidas públicas de conservação e uso preventivo dos recursos ambientais, principalmente aqueles relacionados ao cultivo de solos, e que a resolução espacial mais adequada é de 200 metros para grandes bacias. Esta resolução não é, talvez, a realidade para pequenas bacias, devendo ser realizado estudos complementares.
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Graciosa, Melissa Cristina Pereira. "Modelo de seguro para riscos hidrológicos com base em simulação hidráulico-hidrológica como ferramenta de gestão do risco de inundações." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-13082010-102943/.
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Recentes catástrofes provocadas por eventos hidrológicos extremos ocorridos nas cidades brasileiras revelaram a fragilidade das atuais políticas empregadas no tratamento do problema das inundações. Freqüentemente, faltam recursos mesmo para as ações emergenciais, e as ações estruturais aplicadas muitas vezes consistem de medidas pontuais e paliativas que não promovem soluções definitivas no âmbito de bacia hidrográfica. O tratamento do problema de inundações de maneira orientada ao risco, em lugar da tradicional abordagem orientada a evento, é uma alternativa que propicia soluções mais eficientes e sustentáveis. A gestão do risco de desastres naturais compreende três níveis: antes, durante e após o evento extremo, com base em ações que visam à redução do risco por meio de suas três componentes: ameaça, vulnerabilidade e exposição. No contexto do desenvolvimento e fortalecimento econômico do Brasil, os seguros para desastres naturais têm papel importante como agentes de transferência do risco que possibilitam a recuperação econômica das áreas atingidas. Vencido o entrave inicial à implantação de seguros deste tipo no Brasil, que foi a abertura, em 2007, ao mercado ressegurador internacional, o desafio que se apresenta atualmente é o desenvolvimento de metodologias que possibilitem relacionar a magnitude do evento natural extremo com o prejuízo monetário correspondente e o prêmio de seguro que possibilite ressarcir as perdas contabilizadas, considerando cenários de longo prazo. O modelo de seguros proposto neste trabalho é baseado no princípio de seguro indexado, em que o pagamento de indenizações é vinculado a uma variável climática, no caso, a vazão máxima de cheia. Foram utilizadas ferramentas de modelagem e simulação hidráulico-hidrológica para gerar mapas de risco de inundação e quantificar os prejuízos correspondentes às cheias de diferentes probabilidades de ocorrência. Em seguida, foi simulado um modelo econômico de seguros para obter o prêmio ótimo capaz de ressarcir os prejuízos estimados, considerando diferentes cenários de longo prazo. Um estudo de caso ilustra a aplicação do método em uma bacia hidrográfica caracterizada por problemas recorrentes de inundação, dado o processo de expansão urbana que nela vem ocorrendo. Foram avaliadas faixas de cobertura em função dos períodos de retorno das cheias correspondentes. Os resultados mostraram que a metodologia é adequada à análise do comportamento do fundo de seguros. Resseguros podem ser requeridos para o tratamento de eventos de períodos de retorno muito extremos.Recent disasters caused by extreme hydrological events, occurred in Brazilian cities, have exposed how fragile the current policies are to manage such situation. Often, a lack of resources is observed even for emergency actions, while structural actions commonly consist of palliative and punctual measures that do not promote real solutions considering the watershed sphere. To face the problem based on a risk-oriented approach instead of the traditional event-oriented approach represents an alternative that provides more efficient and sustainable solutions. Disaster risk management comprehends three time-oriented phases: before, during and after the extreme event, each phase focusing on the three risk\'s components: hazard, vulnerability and exposition. As Brazil\'s economy grows stronger and more stable, natural disaster insurance plays an important role as a risk transfer mechanism, promoting economic resilience in damaged areas. After the opening of the reinsurance\'s market in 2007, Brazil\'s challenge is to develop methodologies relating extreme events hazard with its corresponding damage and an insurance premium, in a way that the losses can be refunded in long term sceneries. The insurance model proposed in this work is based on the indexed insurance, where the refunds are linked to a weather variable - the maximum discharge. Hydrologic and hydraulic simulations were developed in order to generate risk maps and to quantify the damage related to floods with different return periods. Afterwards, a flood insurance model was simulated in order to obtain the optimal insurance premium sufficient to refund the expected damage for long term sceneries. A case study illustrates the method in a watershed where flood events are frequent due to urban occupation. The insurance coverage associated to each flood return period was examined and the results have shown that the methodology is suitable for the analysis of the flood insurance\'s behavior. Reinsurance may be required to deal with extreme events with high return periods.
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Lang, Patrick T., and Thomas III Maddock. "SIMULATION OF GROUND-WATER FLOW TO ASSESS THE EFFECTS OF PUMPING AND CANAL LINING ON THE HYDROLOGIC REGIME OF THE MESILLA BASIN: Dona Ana County, New Mexico & El Paso County, Texas." Department of Hydrology and Water Resources, University of Arizona (Tucson, AZ), 1995. http://hdl.handle.net/10150/617628.
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This study, which is to provide information to a settlement over the rights to water
resources in the Mesilla Basin, uses a groundwater model to estimate how pumping in the
basin affects the hydrologic regime.
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Matji, Maselaganye Petrus. "Comparative modelling of phosphorous production in rural catchments." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51657.
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Thesis (M.Ing.)--Stellenbosch University, 2000.ENGLISH ABSTRACT: The objective of this research has been to compare nonpoint sources assessment techniques for simulating phosphorous production in rural catchments which have a variety ofland use types. Four nonpoint source assessment techniques capable of simulating phosphorous production, operating at different spatial and temporal resolutions, were selected after an intensive literature review. The model selection criteria included the capability to simulate phosphorous production, the need for the study to cover a range of spatial and temporal resolutions, model data requirements, model affordability and availability in South Africa. The models selected using these criteria are the Phosphorous Export Model (PEM) (Weddepohl & Meyer, 1992), Impoundment and River Management and Planning Assessment Tool for Water Quality Simulation Model (IMPAQ) (DWAF,1995), the Hydrological Simulation Program Fortran (HSPF) (Bricknell,1993) and the Agricultural Catchments Research Unit Model (ACRU) (Smithers and Caldecott, 1994). Four ofthe study catchments were selected within the Berg River basin in the Western Cape and the remaining four were selected within the Amatole catchments in the Eastern Cape. The four subcatchments in the Berg River basin are the Twenty-Four Rivers, Leeu River, Kompanjies River and Doring River catchments and the four in the Amatole catchments are the Upper Buffalo, Cwencwe, Yellowwoods and Gqunube River catchments. The range of land use/cover types comprises: Western Cape catchments : wheat, grapes, natural vegetation and forestry Eastern Cape catchments : natural vegetation and forestry The PEM and IMPAQ models were applied reasonably successfully to all the catchments to simulate phosphorous production, with the observed flow as the input. The HSPF model could not successfully be applied to the catchments to simulate both the catchment hydrology and phosphorous production. Hence, the investigation into HSPF was abandoned, and in its place, the ACRU daily phosphorous yield model was incorporated at a fairly late stage in the research. ACRU was applied to only the Western Cape catchments. The estimated parameters for different land use types were compared to investigate the potential for parameter transfer in space and time. Both the PEM and IMP AQ models showed promise that land use parameters could be transferred in time for catchments located in the Western Cape catchments, but did not show promise for catchments located in the Eastern Cape. The IMPAQ model showed promise that land use parameters could be transferred in space for catchments located in the Eastern Cape, but did not perform as well in the Western Cape catchments. The PEM model showed promise that land use parameters could be transferred in space for catchments located in the Western Cape, but did not perform as well in the Eastern Cape. Since the ACRU phosphorous yield model was included at a late stage of the research, the potential for land use parameter transfer in space and time could not investigated. The model results were verified at the relevant flow and water quality gauging stations. The ACRU phosphorous model verification results showed promise for catchments located in humid parts of the Berg River basin, but did not perform as well in the catchment located in the semi-arid part. RECOMMENDATIONS FOR FURTHER RESEARCH: I. Intensive research should be undertaken to develop a database ofland use parameters/ export coefficients related to phosphorous production (and other non-conservative constituents) in South African catchments. Availability of these parameters would make phosphorous modelling much easier. HSPF should be configured and calibrated, more especially its water quality component, for catchments with hourly rainfall and rainfall stations located within/on the catchment boundaries, to investigate its performance under South African conditions. Given the complexity of the HSPF algorithms and the time required to familiarise oneself with the model, it is recommended that such an investigation be undertaken which is not inclusive of any other models. The spatial resolution ofPEM is extremely coarse, and should be improved to allow the user to partition the total flow in the catchment according to contributions from the variety ofland use types and to estimate soluble and particulate phosphorous parameters for each land use type. A study should be undertaken to investigate the potential for the ACRU phosphorous yield model parameter transfer in time and space. Sampling frequency of water quality data in South Africa should be improved, because it is difficult to assess the performance of the calibrated water quality models, more especially phosphorous export models, due to a lack of continuous data sets. Rainfall data collection in gauged catchments, more especially Western Cape catchments (e.g. Twenty-Four Rivers, Leeu, Kompanjies and the Doring River catchments), should be improved. There should be at least one rainfall gauging station located within the catchment boundaries. This would contribute towards achieving reasonable hydrological calibration or verification. Since runoff is the driving factor for water quality components, improved hydrological calibration/verification would result in reasonable water quality calibration/verification.
AFRIKAANSE OPSOMMING: Die doel van die navorsing was om die simulering van fosfaat produksie in landelike gebiede, wat 'n verskeidenheid grondgebruike het, met behulp van nie-punt bron evaluerings tegnieke te evulaeer. Vier nie-punt bron evaluerings tegnieke, met die vermoë om fosfaat produksie op verskillende ruimtelike en tyds resolusies te simuleer, is gekies na 'n intensiewe ondersoek van beskikbare literatuur. Die kriteria vir die keuse van die model het ingesluit die vermoë om fosfaat produksie te simuleer, die behoefte vir die studie om 'n reeks van ruimtelike en tyds resolusies te simuleer, model data vereistes, model bekostigbaarheid en beskikbaarheid in Suid Afrika. Die gekose modelle, gebaseer op bogemelde kriteria, was die PEM, IMPAQ, HSPF en ACRU modelle. Vier van die opvanggebiede gebruik in die studie, was in die Bergrivier bekken in die Wes-Kaap en vier was in die Amatole opvanggebiede in die Oos-Kaap. Die vier opvanggebiede in die Bergrivier bekken is die Vier-en- Twentigriviere, Leeurivier, Kompanjiesrivier en die Doringrivier en die vier opvanggebiede in die Amatole opvanggebiede is die Bo-Buffels, Cwencwe, Yellowwoods, en die Gunubierivier opvanggebiede. Grondgebruik beslaan die volgende: Wes-Kaap opvanggebiede : koring, druiwe, natuurlike weiding en plantasies. Oos-Kaap : natuurlike plantegroei en plantasies Die PEM en IMPAQ modelle is met redelike sukses in al die opvanggebiede gebruik vir die simulasie van fosfaat produksie, met die waargenome vloei as invoer. Die HSPF model kan nie met enige sukses gebruik word om beide die opvanggebied hidrologie en fosfaat produksie, te simuleer nie. Die HSPF model is dus uitgeskakel en in 'n redelike laat stadium van die studie met die ACRU daaglikse fosfaat leweringsmodel vervang. Die ACRU model is net op die Wes-Kaap opvanggebiede toegepas. Die beraamde parameters vir die verskillende grondgebruik tipes is vergelyk om die potensiaal vir parameter oordrag in ruimte en tyd te ondersoek. Beide die PEM en IMPAQ modelle het belowend vertoon ten opsigte van die oordrag van grondgebruik parameters in tyd vir opvanggebiede in die Wes- Kaap, maar het geensins belowend vertoon vir die Oos-Kaap opvanggebiede nie. Die IMPAQ model het belowend vertoon ten opsigte van die ruimtelike oordrag van grondgebruik parameters vir die Oos-Kaap opvanggebiede, maar het nie so goed vertoon in die Wes-Kaap opvanggebiede nie. Die PEM model het belowend vertoon ten opsigte van die ruimtelike oordrag dat grondgebruikte parameters in die Wes-Kaap opvanggebiede is, maar het nie so goed in die Oos-Kaap opvanggebiede vertoon nie. Aangesien die ACRU fosfaat leweringsmodel op 'n laat stadium van die navorsing ingesluit is, kan die potensiaal vir die oordrag van grondgebruik parameters in ruimte en tyd nie ondersoek word nie. Die model resultate is by die toepaslike vloei en waterkwaliteit meetstasies geverifiëer Die resultate van die ACRU fosfaat model verifikasie het belowend vertoon vir opvangebiede in die humiede gedeeltes van die Bergrivier bekken, maar het nie so goed vertoon in die semi-droeë deel van die opvangebied nie. AANBEVELINGS VIR VERDERE NAVORSING : Y4 Intensiewe navorsing moet onderneem word ten einde in 'n databasis van grondgebruik parameters/oordrag koëffisiente met betrekking tot fosfaat produksie (en ander niekonserwatiewe bestandelle ) in Suid Afrikaanse opvanggebiede op te bou. Beskikbaarheid van hierdie parameters sal fosfaat modellering vergemaklik. Die HSPF model moet opgestel en gekalibreer word, meer spesifiek ten opsigte van die waterkwaliteit komponent, vir opvanggebiede met uurlikse reënval en reënvalstasies binne of op die opvanggebied grense, om die model se vertoning onder Suid Afrikaanse omstandighede te ondersoek. Gegewe die kompleksiteit van die HSPF algoritmes en tyd benodig om met model vertroud te raak, word dit aanbeveel dat so 'n ondersoek onderneem word met uitsluiting van die ander modelle. Die ruimtelike resolusie van die PEM model is uitermatig grof, en behoort verbeter te word ten einde die gebruiker toe te laat om die totale vloei in die opvanggebied in ooreenstemming met die bydraes van die onderskeie grondgebruik tipes te verdeel en om oplosbare en partikulere fosfaat parameters vir elke grondgebruik tipe te beraam. 'n Studie om die potensiaal vir die ruimtelike en tydsoordrag van die ACRU fosfaat leweringsmodel parameters te ondersoek, moet onderneem word. Die frekwensie van waterkwaliteit monitering in Suid Afrika moet verbeter word, aangesien dit moelik is om, weens 'n gebrek aan deurlopend waargenome data, die vertoning van gekalibreerde waterkwaliteit modelle te ondersoek, meer spesifiek nog fosfaat uitvoer modelle. Reënval inligting versameling in gemete opvanggebied, meer spesifiek die Wes-Kaap opvanggebiede (bv.Vier-en-Twintigriviere, Leeu, Kompanjies en Doringrivier opvanggebiede), behoort verbeter te word. Daar behoort ten minste een reënval stasie binne die opvanggebied grense te wees. Dit sal bydra tot die bereiking van redelike hidrologiese kalibrasie ofverifikasie. Aangesien afloop die dryfveer van die waterkwaliteit komponente is, sal verbeterde hidrologiese kalibrasie/verifikasie lei tot redelike waterkwaliteit kalibrasie/verifikasie.
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Gonzalez, Alba Maria Guadalupe Orellana. "Modelo de simulação dinâmica para valoração ecológica de serviços ecossistêmicos hídricos nas bacias hidrográficas dos rios Piracicaba, Capivari e Jundiaí." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/91/91131/tde-14022011-163736/.
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O objetivo principal desta pesquisa foi desenvolver um modelo de simulação dinâmica para a valoração ecológica de serviços ecossistêmicos hídricos, baseado em princípios de Dinâmica de Sistemas com o auxílio do software STELLA. A hipótese básica adotada foi que: a valoração ecológica dos serviços ecossistêmicos deve contar com uma ferramenta integradora dos elementos envolvidos na modelagem ecológica como requisito básico para compreensão da dinâmica ecossistêmica que gera fluxos de serviços ecossistêmicos hídricos (SEH). Os SEH são os benefícios gerados a partir das complexas interações, entre os componentes do ciclo hidrológico e que tem a ver com a preservação tanto em quantidade como em qualidade da oferta de água. O modelo foi desenvolvido, através de uma análise sistêmica dos processos ecossistêmicos compreendidos dentro do ciclo hidrológico, foram determinadas as principais variáveis e suas respectivas inter-relações, de acordo com a estrutura desse ciclo. Essa estrutura foi representada no diagrama causal, que serviu de base à elaboração do diagrama de estoque e fluxo, por meio do qual se estabeleceu o modelo matemático que permitiu efetuar a simulação numérica. A escala temporal de aplicação do modelo é diária e foram efetuadas 365 simulações, o que permitiu estimar fluxos anuais de SEH. O modelo foi parametrizado na sub-bacia das Posses, Município de Extrema, Minas Gerais; aqui esta sendo implementado o primeiro projeto piloto, baseado na relação floresta-água, de pagamentos por SEH do Brasil. Foram examinados 36 cenários, com o objetivo de avaliar o impacto que têm variáveis como: textura de solo, altura da vegetação, índice de área foliar e profundidade do lençol freático na geração dos fluxos de SEH em água na superfície, infiltrada e armazenada; porém foi avaliado como estes incidem de forma quantitativa na manutenção da oferta de água disponível. O modelo desenvolvido permitiu aumentar a compreensão dos fluxos de SEH, o que representa uma ferramenta de elevado potencial de aplicação nas fases de definição de âmbito, de avaliação de alternativas e monitoramento de esquemas de pagamentos por SEH no Brasil.The main objective of this research was to develop a dynamic simulation model to valuate ecological hydrological ecosystem services. The principles of System Dynamics were applied using the software STELLA. A basic hypothesis was adopted: ecological valuation of ecosystem services must use a tool to integer all the elements involved in ecological modeling, as a basic requirement to understand the ecosystem dynamic that generates water fluxes as hydrological ecosystems services (HES). HES are the benefits generated from complex interactions that occur within the hydrologic cycle; those interactions deals with the preservation of available water, in quantity and quality. The model was developed after a systemic analysis of the ecosystem processes involved in the hydrologic cycle; pointing out the main variables and the interrelations that constitute it. Then, the structure of those relations was represented in a causal diagram; becoming the base to built up the stocks and flows diagram. This later diagram established the mathematical model that allowed the numerical simulation. The time step of the model is one day during 365 days, estimating annual water HES. The model was parameterized at Poses sub-watershed, Extrema County, Minas Gerais. In Extrema was established the first payment for HES project in Brazil, based on the relationship between forest land and water availability. Thirty six scenarios were studied considering surface, infiltrated and stored water services fluxes; affecting the availability of water. The objective of those scenarios was to evaluate the impact that variables such as: soil texture, vegetation height, leaf area index and groundwater depth have on water flux generation. The model developed enables to increase the understanding of HES fluxes, becoming a tool with a broad spectrum of applications during the stages of assessing and scoping alternatives for payment of environmental services and to monitor HES programs in Brazil.
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Mounir, Adil. "Development of a Reservoir System Operation Model for Water Sustainability in the Yaqui River Basin." Ohio University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1513880139368117.
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Amaral, Daniele Pereira Batista. "Aplicação do modelo hidrológico SWMM na gestão das águas pluviais urbanas: estudo de caso da bacia hidrográfica do Rio Morto, Rio de Janeiro." Universidade do Estado do Rio de Janeiro, 2014. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=7984.
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O crescimento da população e dos núcleos urbanos durante o século XX, sobretudo nos países em desenvolvimento, contribuiu para o aumento das áreas impermeáveis das bacias hidrográficas, com impactos importantes nos sistemas de drenagem urbana e na ocorrência de enchentes associadas. As enchentes trazem prejuízos materiais, na saúde e sociais. Recentemente, têm sido propostas práticas conservacionistas e medidas compensatórias, que buscam contribuir para o controle das enchentes urbanas, através do retardo do pico e amortecimento dos hidrogramas. Modelos matemáticos hidrológicos-hidráulicos permitem a simulação da adoção destas medidas de controle, demonstrando e otimizando sua localização. Esta dissertação apresenta os resultados da aplicação do modelo hidrológico Storm Water Management Model (SWMM) à bacia hidrográfica de estudo e representativa do rio Morto localizada em área peri-urbana em Jacarepaguá na cidade do Rio de Janeiro, com área de 9,41 km. O processamento do modelo SWMM foi realizado com o apoio da interface Storm and Sanitary Analysis (SSA), integrada ao sistema AutoCAD Civil 3D. Além da verificação da adequabilidade do modelo à representação dos sistemas hidrológico e hidráulico na bacia, foram desenvolvidos estudos para dois cenários como medidas de controle de enchentes: cenário 1, envolvendo implantação de um reservatório de detenção e, cenário 2, considerando a implantação de reservatórios de águas pluviais nos lotes. Os hidrogramas resultantes foram comparados ao hidrograma resultante da simulação nas condições atuais. Além disso, foram avaliados os custos associados a cada um dos cenários usando o sistema de orçamento da Empresa Rio Águas da PCRJ. Nas simulações foram adotadas a base cartográfica, e os dados climatológicos e hidrológicos previamente observados no contexto do projeto HIDROCIDADES, Rede de Pesquisa BRUM/FINEP, na qual este estudo se insere. Foram representados os processos de geração e propagação do escoamento superficial e de base. Durante o processo de calibração, realizou-se a análise de sensibilidade dos parâmetros, resultando como parâmetros mais sensíveis os relativos às áreas impermeáveis, especialmente o percentual de área impermeável da bacia (Ai). A calibração foi realizada através do ajuste manual de sete parâmetros do escoamento superficial e cinco do escoamento de base para três eventos. Foram obtidos coeficientes de determinação entre 0,52 e 0,64, e a diferença entre os volumes escoados e observados entre 0,60% e 4,96%. Para a validação do modelo foi adotado um evento pluviométrico excepcional observado na cidade em abril de 2010, que à época causou enchentes e grandes transtornos na cidade. Neste caso, o coeficiente de determinação foi igual a 0,78 e a diferença entre volumes foi de 15%. As principais distorções entre hidrogramas observados e simulados foram verificados para as vazões máximas. Em ambos os cenários as enchentes foram controladas. A partir destes estudos, pôde-se concluir que o melhor custo-benefício foi o cenário 2. Para este cenário, foi observado maiores amortecimento e retardo da vazão de pico do hidrograma, igual a 21,51% da vazão simulada para as condições atuais da bacia. Os custos de implantação orçados para os reservatórios de lote ficaram 52% a menos do que o do reservatório de detenção.Population and urban occupation growth during 20th century, mainly in underdeveloped countries, contributed for increasing impermeable surfaces in drainage basins, leading to important impacts on urban drainage systems and associated floods. Floods cause material losses, healthy and social problems, apart of great disruptions in large citys mobility. Recently, a number of, non-conventional, conservative practices and compensatory measurements have been proposed seeking urban flood control, by lengthening hydrographs time lag and promoting shallow rising limb. Hydrologic-hydraulic mathematical models allow the simulation of these flood control measurements, demonstrating and optimizing their location, maximizing the benefits of their application. This dissertation presents the results of the application of the Storm Water Management Model (SWMM) to the representative and under study catchment of Morto River, with 9,41 km2 of area, located in a peri urban area, in Jacarepaguá, city of Rio de Janeiro, Brazil. Storm and Sanitary Analysis (SSA) tool integrated to AutoCAD Civil 3D System supported the model processing. Apart of verifying the representativeness of the hydrologic-hydraulic modelling system to the physical processes in the Morto river catchment, two different scenarios were studied as means of flood control: scenario 1, involving the simulation of one retention reservoir and, scenario 2, involving the use of multiple distributed rainwater reservoirs in the lots. The resulting hydrographs were compared to the one for catchments actual conditions. Additionally, the associated costs for each scenario were evaluated applying the official budget system of Rio Águas of Rio de Janeiro Council. It was applied the cartographic data base, climatological and hydrological data obtained in the HIDROCIDADES Project, FINEP BRUM Research Network, under which this work has been developed. The processes of generation and propagation of runoff and baseflow were modelled. During the calibration process, was performed a sensitivity analysis of the parameters, resulting as the most sensitive parameters those related to impervious areas, especially the percentage of impervious area in the basin (Ai). Manually calibration was performed, seven parameters for runoff simulation and five for baseflow were adjusted, for three events, presenting values for the coefficient of determination between 0.52 and 0.64. The difference between simulated and observed volumes varied from 0.60% to 4.96 %. Model validation was performed for an exceptional rainfall event in April 2010, which caused floods in many places in the city. In this case, the coefficient of determination was equal to 0.78 and difference in runoff volumes equal to 15 %, being identified that the main differences are in peak flows discharges. In both scenarios floods were totally controlled. It was concluded that the best cost-benefit was for scenario 2. For this scenario it was observed the best result, considering both reduction on hydrographs peak flow discharge and increasing on time to peak. Peak flow discharge was reduced by 21,51% when compared to the simulated hydrograph for catchments current stage. It was found a much lower cost for scenario 2, the budget was 52% less than the budget for scenario 1.
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Rousset, Regimbeau Fabienne. "Modélisation des bilans de surface et des débits sur la France, application à la prévision d'ensemble des débits." Phd thesis, Université Paul Sabatier - Toulouse III, 2007. http://tel.archives-ouvertes.fr/tel-00197071.
Full textAbstract:
Ce travail de thèse s'appuie sur l'utilisation du modèle couplé hydro-météorologique SAFRAN-ISBA-MODCOU.D'abord, la modélisation couplée du bassin de la Seine est mise en place, en utilisant une représentation détaillée des aquifères du bassin. La capacité de SIM à simuler les différentes composantes des bilans d'eau et d'énergie, le comportement du souterrain, et donc les débits, est présentée. En particulier, SIM est évalué pour la simulation des crues lentes de la Seine à Paris.
Ensuite, une chaîne temps réel de prévision d'ensemble des débits sur la France, basée sur SIM, est construite, où ISBA et MODCOU sont forcés par les prévisions d'ensemble météorologiques du CEPMMT désagrégées. Une analyse statistique de la qualité des prévisions d'ensemble de précipitations désagrégées et des prévisions d'ensemble de débit est effectuée sur près d'un an de prévision. Enfin, une étude des prévisions d'ensemble de plusieurs cas de grandes crues du passé récent est présentée.