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Rogers, C. "Further development of distributed hydrological models with reference to the Institute of Hydrology distributed model." Thesis, University of Bristol, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373726.
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Kim, JongKwan. "The Calibration and Uncertainty Evaluation of Spatially Distributed Hydrological." DigitalCommons@USU, 2013. https://digitalcommons.usu.edu/etd/1437.
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In the last decade, spatially distributed hydrological models have rapidly advanced with the widespread availability of remotely sensed and geomatics information. Particularly, the areas of calibration and evaluation of spatially distributed hydrological models have been attempted in order to reduce the differences between models and improve realism through various techniques. Despite steady efforts, the study of calibrations and evaluations for spatially distributed hydrological models is still a largely unexplored field, in that there is no research in terms of the interactions of snow and water balance components with the traditional measurement methods as error functions. As one of the factors related to runoff, melting snow is important, especially in mountainous regions with heavy snowfall; however, no study considering both snow and water components simultaneously has investigated the procedures of calibration and evaluation for spatially distributed models. Additionally, novel approaches of error functions would be needed to reflect the characteristics of spatially distributed hydrological models in the comparison between simulated and observed values. Lastly, the shift from lumped model calibration to distributed model calibration has raised the model complexity. The number of unknown parameters can rapidly increase, depending on the degree of distribution. Therefore, a strategy is required to determine the optimal degree of model distributions for a study basin. In this study, we will attempt to address the issues raised above. This study utilizes the Research Distributed Hydrological Model (HL-RDHM) developed by Hydrologic Development Office of the National Weather Service (OHD-NWS). This model simultaneously simulates both snow and water balance components. It consists largely of two different modules, i.e., the Snow 17 as a snow component and the Sacramento Soil Moisture Accounting (SAC-SMA) as a water component, and is applied over the Durango River basin in Colorado, which is an area driven primarily by snow. As its main contribution, this research develops and tests various methods to calibrate and evaluate spatially distributed hydrological models with different, non-commensurate, variables and measurements. Additionally, this research provides guidance on the way to decide an appropriate degree of model distribution (resolution) for a specific water catchment.
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Susilo, Gatot Eko. "A comparison of distributed hydrological models for the Boreal forest of northern Manitoba." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0019/MQ53232.pdf.
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Younger, Philip M. "High resolution numerical weather prediction, distributed hydrological models and uncertainty - towards a unified approach." Thesis, Lancaster University, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.507280.
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VanWerkhoven, Curtis. "Performance assessment of short-term hydrological forecasts in small, coastal watersheds with complex terrain using fully-distributed hydrological and meteorological models." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/54586.
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Accurate and reliable short-term streamflow forecast systems are beneficial for non-storage hydroelectric operators to minimize costs associated with foregoing electricity market opportunities because of held reserves due to forecast error and those making decisions based on flood risks. Accurate real-time forecasting on hourly and daily intervals with lead times less than three days remains a challenge in small, coastal, mountainous watersheds of the Pacific Northwest. This thesis examines a real-time streamflow forecasting system in which a physically-based, fully-distributed coupled MIKE SHE/MIKE 11 hydrologic model is driven by the distributed output of a 1.3 km gridded high-resolution numerical weather prediction (NWP) model. The model performance in simulating hydrological processes is evaluated in the model calibration and validation phases, and the forecast accuracy and reliability is evaluated in the forecast verification phase. Both performance evaluations are completed with graphical and statistical techniques based on a wide range of statistical metrics. In addition to the performance, the forecast skill is evaluated relative to alternative reference forecasts including persistence and historical climatological forecasts. The hydrologic model and forecasting system are applied to the Coquitlam River above Coquitlam Lake watershed located in the coastal mountains of southwestern British Columbia, Canada. The hydro-climate regime in the watershed is pluvio-nival, flashy, and with negligible glacier melt. High flows have a bi-modal distribution, characterized by high flows in May and June due to snowmelt and in fall (November) due to Pacific frontal systems that can bring significant precipitation. The MIKE SHE/MIKE 11 model performs well during the model calibration and validation phases, demonstrating accuracy and reliability in simulating the hydrological processes in the watershed with a one year calibration period. In addition, the forecast system provides a reliable forecast for hourly and daily mean streamflow with considerable forecast skill in comparison to reference forecasts for lead times of one to three days. MIKE SHE/MIKE 11 is demonstrated as a suitable fully-distributed, physically-based model for river forecasts based on high-resolution NWP models, and that there is the opportunity for short-term forecast skill in small, mountainous, Pacific Northwest watersheds with limited observed data.Applied Science, Faculty of
Civil Engineering, Department of
Graduate
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Sood, Aditya. "Integrated watershed management as an effective tool for sustainable development using distributed hydrological models in policy making /." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 190 p, 2009. http://proquest.umi.com/pqdweb?did=1833621281&sid=2&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Souza, Rávila Marques de. "Modelo hidrológico distribuído unidimensional para bacias hidrográficas peri-urbanas." Universidade Federal de Goiás, 2014. http://repositorio.bc.ufg.br/tede/handle/tde/2965.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
This study aimed to develop and calibrate a distributed hydrological model used for a one-dimensional drainage of a peri-urban catchment using the optimization multi-objective method Non -dominated Sorting Genetic Algorithm (NSGA - II) for model calibration. Computational algorithms developed in MATLAB environment were adopted to make this study possible. This model allows a precipitation event to set the surface runoff hydrograph at any position of the watershed (planes or channels) regarding infiltration effect and soil physical characteristics. Objective functions were defined and used simultaneously to calibrate the model. From sensitivity analysis performed, it was found that the model is more affected by the parameters related to permeable areas. The model fit was very good, illustrating the applicability of multi-objective calibration in exploring ideal area and to obtain ideal solutions. Validation proved the efficiency of the model used for other different rainfall events in Samambaia stream basin, generating outputs with good accuracy and optimal theoretical value results for Nash & Sutcliffe coefficients of efficiency near the area region.
O presente trabalho propôs desenvolver e calibrar um modelo hidrológico distribuído unidimensional aplicado a drenagem de uma bacia hidrográfica peri-urbana utilizando o método de otimização multi-objetivo Non-dominated Sorting Genetic Algorithm (NSGA-II) para a calibração do modelo. Para tornar possível a realização deste trabalho foram adotadas rotinas computacionais desenvolvidas em ambiente MATLAB. O modelo desenvolvido permite, para um evento de precipitação, determinar o hidrograma de escoamento superficial em qualquer posição da bacia hidrográfica (planos ou canais) considerando o efeito da infiltração e das características físicas do solo. Foram definidas funções objetivo e aplicadas simultaneamente na calibração do modelo. Da análise de sensibilidade realizada, verificou-se que o modelo é mais impactado pelos parâmetros relativos às áreas permeáveis. O ajuste do modelo foi muito bom, ilustrando a aplicabilidade da calibração multi-objetivo em explorar a região ideal e obter soluções ideais. A validação comprovou a eficiência do modelo, aplicada a outros eventos chuvosos diferentes ocorridos na bacia do córrego Samamabaia, gerando saídas com acurácia satisfatória e resultados para os coeficientes de eficiência Nash & Sutcliffe próximos à região do valor ótimo teórico.
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Davison, Bruce. "Snow Accumulation in a Distributed Hydrological Model." Thesis, University of Waterloo, 2004. http://hdl.handle.net/10012/793.
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The cryosphere is defined as the portions of the earth where water is in solid form. It represents a very important part of the hydrologic cycle, affecting ecological, human and climate systems. A number of component models describing the energy and mass balances of a snowpack have been developed and these component models are finding their way into watershed models and land surface schemes. The purpose of this thesis is to examine the incorporation of a number of snow processes in the coupled land-surface-hydrological model WATCLASS.
The processes under consideration were mixed precipitation, variable fresh snow density, maximum snowpack density, canopy interception and snow-covered area (SCA). The first four of these processes were based on similar work done by Fassnacht (2000) on a watershed in Southern Ontario. In the case of this thesis, the work was completed on a basin in Northern Manitoba. A theory of the relationship between snow-covered area and average snow depth was developed and an algorithm was developed to implement this theory in WATCLASS. Of the five snow processes considered, mixed precipitation was found to have the greatest impact on streamflow while the new canopy interception algorithm was found to have the greatest impact on sensible and latent heat fluxes. The development of a new relationship between SCA and average snow depth was found to have a minimal impact in one study case, but a significant impact on the sensible and latent heat fluxes when snow fell on a pack that had begun to melt and was partially free of snow. Further study of these snow processes in land-surface-hydrologic models is recommended.
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Zhang, Xuesong. "Evaluating and developing parameter optimization and uncertainty analysis methods for a computationally intensive distributed hydrological model." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-3091.
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Sokrut, Nikolay. "The Integrated Distributed Hydrological Model, ECOFLOW- a Tool for Catchment Management." Doctoral thesis, Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-237.
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Hunukumbura, J. M. P. B. "Distributed hydrological model transferability across basins with different physio-climatic characteristics." 京都大学 (Kyoto University), 2009. http://hdl.handle.net/2433/126504.
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Kyoto University (京都大学)0048
新制・課程博士
博士(工学)
甲第14933号
工博第3160号
新制||工||1474(附属図書館)
27371
UT51-2009-M847
京都大学大学院工学研究科都市環境工学専攻
(主査)教授 椎葉 充晴, 教授 寶 馨, 准教授 立川 康人
学位規則第4条第1項該当
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Horner, Ivan. "Design and evaluation of hydrological signatures for the diagnostic and improvement of a process-based distributed hydrological model." Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALU014.
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L’évaluation des modèles hydrologiques est généralement basée sur des comparaisons des séries de débit observées et simulées à l’aide de critères de performance tels que le Nash-Sutcliffe Efficientcy. Bien que cette approach fournisse des mesures pertinentes de la performance prédictive d’un modèle, elle ne fournit que très peu d’informations sur les raisons d’une bonne ou d’une mauvaise performance. Gupta et al. (2008) ont proposé d’utiliser plutôt des signatures hydrologiques, des indicateurs qui caractérisent le comportement d’un bassin versant. Étant donné que les signatures hydrologiques peuvent être liées aux processus hydrologiques, la comparaison des signatures hydrologiques observées et simulées permet l’évaluation du modèle tout en offrant des diagnostics, i.e. des indications sur les processus hydrologiques qui y sont bien ou mal représentés.Dans cette thèse de doctorat, nous nous concentrons sur l’interprétation et le pouvoir diagnostique des signatures hydrologiques et comment celles-ci peuvent être utilisées pour guider l’amélioration d’un modèle distribué. Nous présentons la construction d’un jeu de signatures hydrologiques, utilisant uniquement des données largement disponibles – précipitations, débit et température de l’air – pour caractériser le fonctionnement hydrologique de 4 sous-bassins versants (Sud-Est de la France) et 10 bassins versants de montagne à influence nival (Southern Sierra, Californie, États-Unis). Des signatures hydrologiques existantes et des nouvelles sont sélectionnées et/ou développées. Collectivement, elles permettent de caractériser le comportement de bassins versants dans une grande variété de contextes hydro-climatiques. En nous concentrant sur les processus de neige, des mesures de neige supplémentaires nous permettent d’évaluer la pertinence des signatures hydrologiques dédiées aux processus nivaux. Par ailleurs, le modèle J2000 est déployé sur le bassin versant de l’Ardèche et une analyse de sensibilité est réalisée afin de comprendre comment les signatures hydrologiques sont liées aux paramètres du modèle. Cela nous permet de déterminer la façon dont elles doivent être interprétées dans le contexte du modèle J2000 de l’Ardèche et permet l’évaluation de leur pouvoir diagnostic. Enfin, en combinant les résultats de l’analyse de sensibilité avec des comparaisons entre signatures observées et simulées, nous entreprenons un diagnostic approfondi du modèle afin de dériver et tester des recommandations pour son amélioration. Nous identifions des déficiences du modèle, principalement liées au stockage de l’eau souterraine et des sols, mettant en évidence des problèmes de représentation spatiale des propriétés géologiques et pédologiquesThe evaluation of hydrological models is typically based on comparisons of observed and sim-ulated streamflow time series using performance metrics such as the Nash-Sutcli˙e Eÿciency. Although it provides relevant measures of the predictive performance of a model, this type of approach provides very little information on the reasons behind good or bad performance. Instead, Gupta et al. (2008) proposed to use hydrological signatures which are indicators that characterize catchment behaviors. Because they can be related to hydrological processes, using them when comparing observation with simulation enable the evaluation of the model while o˙ering diagnostics, i.e. indications on the hydrological processes that are well or badly repre-sented in the model.In this PhD thesis, we focus on the interpretations and diagnostic power of hydrological signatures and how they can be used to guide the improvement of a distributed model. We present the building of a set of hydrological signatures, using only widely available data – pre-cipitation, streamflow and air temperature – to characterize the hydrological functioning of 4 Ardèche sub-catchments (South East of France) and 10 snow dominated catchments of the Southern Sierra mountains (California, USA). Already existing and new hydrological signatures are selected and/or designed. Collectively, they can characterize catchment behavior in a wide variety of hydro-climatic contexts. We demonstrate the value of additional snow measurements to evaluate the information content of snow dedicated hydrological signatures. In the context of the Ardèche catchment, we set up the J2000 distributed model and use a sensitivity analysis to understand how the hydrological signatures are linked to the model parameters. This provides insights into how they are to be interpreted in the context of the J2000 Ardèche model and allows the assessment of their diagnostic power. Finally, combining the results of the sensi-tivity analysis with comparisons between observed and simulated hydrological signatures, we undertake an in-depth diagnostic of the model to provide and test recommendations for its improvement. Deficiencies of the model functioning are identified, mainly related to soil and groundwater storage and fluxes, highlighting issues in the spatial representation of soil and geological properties
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Castillo, Aldrich Edra. "Spatiotemporal variability of hydrologic response : an entropy-based approach using a distributed hydrologic model." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/90040.
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Thesis: Ph. D. in Hydrology, Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2014.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 179-189).
Basin hydrologic response pertains to the partitioning of precipitation into stream-flow, evapotranspiration, and change in storage. The ability to explain or predict the response has many applications e.g. flood forecasting, water budget studies, and design of hydrological observing systems. However, explaining the response is challenging because it is the combined manifestation of many complex and interrelated factors that naturally vary in space and time, and act over a variety of scales. A possible key is better understanding of the space-time dynamics of the hydrologic state variable - the soil moisture field. This thesis uses the distributed hydrologic model MOBIDIC that uses a single soil layer with dual compartments: a capillary and a gravity reservoir composed of small, and large pores, respectively. Mass and energy fluxes are simultaneously solved using simple linear equations. These make the model computationally efficient. To improve soil moisture simulations, some model modifications were introduced. MOBIDICs ability to simulate the magnitude range and dynamics of soil moisture at the local scale is found comparable with a benchmark model that uses non-linear soil physics relations. We derive an entropy-based dimensionless measure of hydrologic complexity H which measures the distance of a given soil moisture spatial probability distribution from two limiting cases. Using 8 test basins with area of 10⁰-10³ km² and representing semiarid, temperate, and humid climates, it is shown that H effectively tracks the evolution of soil moisture distribution, and captures the interplay between vertical and lateral fluxes. Furthermore, we investigate the relationship of W with observable basin attributes and traditional measures of hydrologic response. Clear and logical relationships emerge only after grouping basins based on similarity. For example, in the semiarid basins, H increases with catchment area, infiltration ratio and baseflow index. For basins of similar size, H is highest in temperate climate, consistent with soil moisture being double-bounded so its variability peaks at intermediate conditions. Finally, although not explicitly coded in MOBIDIC, hysteresis is evident in the discharge-storage plots. It emerges from the use of a dual-pore soil structure that captures the threshold behavior of runoff. R- helps in understanding the mechanisms involved.
by Aldrich Edra Castillo.
Ph. D. in Hydrology
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Miller, Scott N. "Scale effects of geometric complexity, misclassification error and land cover change in distributed hydrologic modeling." Diss., The University of Arizona, 2002. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_2002_216_sip1_w.pdf&type=application/pdf.
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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
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Kaiser, Ilza Machado. "Avaliação de métodos de composição de campos de precipitação para uso em modelos hidrológicos distribuídos." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-17042006-222747/.
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Este trabalho discute a composição de campos de precipitação a partir de duas fontes de dados: os pluviômetros e o radar meteorológico. Estudaram-se métodos baseados somente em dados de pluviômetros, somente em dados de radar, e técnicas que combinam as duas fontes de dados. O objeto de estudo é a bacia do rio Jacaré-Guaçu, que conta com 65 postos pluviométricos e um radar meteorológico, do IPMet-Bauru. Foi feita uma comparação direta entre os campos gerados pelas diversas técnicas, onde foi avaliado o comportamento do índice G (razão entre o registro pluviométrico e a média dos registros de radar dos 9 pixels que circundam o pluviômetro), a capacidade destas técnicas de fornecer a chuva pontual e a altura média diária e anual de chuva por área de integração. Os métodos compostos apresentaram valores pontuais de chuva muito elevados e foram introduzidos fatores limitantes para compensar estas super correções. Os resultados obtidos reproduziram qualitativamente os valores da literatura. Ao analisar a média das chuvas diárias para toda a bacia e para todo o período, utilizando como padrão de comparação o método do Inverso do Quadrado da Distância (IQD), constatou que o radar fornece valores 12% menores, e que os métodos mistos apresentam diferenças na faixa de -0,5 a +16%. Nesta forma de análise existe um ganho ao se utilizar as técnicas mistas, porém ao se trabalhar com valores diários, integrados em sub-bacias, as diferenças atingem valores de -45% até +70%. Estes campos de precipitação foram aplicados em um modelo hidrológico distribuído, de embasamento físico, com 19 parâmetros calibráveis. Trabalhou-se com 10 postos fluviométricos e com 6 anos de dados. A calibração foi feita com dois anos e o restante deles foi usado para validação. Para garantir a comparação entre os resultados usou-se rigorosamente a mesma metodologia de calibração, com apoio de algoritmo genético. Foram utilizadas três funções objetivo: uma para verificação dos picos, outra para recessão e a última para avaliar a diferença de volume. Verificou-se que os melhores resultados foram obtidos para os métodos IQD, Brandes com o maior limitador, Radar e Costa. Nestes métodos, o processo de calibração consegue compensar as diferenças dos campos de precipitação. As diferenças observadas nos campos de precipitação foram reproduzidas nos hidrogramas. Os hidrogramas resultantes da aplicação dos dados de radar não reproduziram bem a recessão e os hidrogramas resultantes dos campos gerados apenas por pluviômetros apresentam picos elevados. As técnicas mistas ora atenuam os picos ora intensificam-nos. Sugere-se mais pesquisa para o desenvolvimento de métodos mistos que explorem as vantagens dos dois equipamentos de medida de chuvaThis work discusses the composition of precipitation fields using two data sources: rain gauges and weather radar. Methods based solely on rain gauges, on weather radar, and techniques that combine these two measurement instruments were studied. The study object is the Jacaré-Guaçu river basin, with 65 rain gauges and a meteorological radar (IPMet-Bauru). A direct comparison of these fields generated by diverse techniques was made to study the following subjects: G index (reason between the rain gauge register and the average of the 9 pixels radar registers that surround the rain gauge), the capacity of these techniques to supply the point rain and the daily and annual mean rain height over an integration area. The combined methods provides very high point values, therefore some limitations were introduced to compensate these super corrections. The literature results were qualitatively reproduced in this study. The daily mean rain height comparative analyses for all the basin, and for all the period, evidenced that the radar supplies to values 12% minors, and that the composed methods present differences from -0,5 up to +16%; the comparison pattern was the Inverse of Square Distance method (ISD). The study of mean rain height calculated over a great period and to the entire river basin shows a profit when using the combined techniques; however, when daily values integrated in sub-basins are used, the differences reach values from -45% until +70%. These precipitation fields had been applied in a distributed hydrologic model, physically based, with 19 calibrated parameters. There were 10 fluviometric stations and 6 years of data. The calibration was made with two years, and that remain data was used for validation. To guarantee the results comparison, the same calibration methodology was rigorously used, with support of genetic algorithm. Three objective functions were used: one for peaks verification, another for recession analyses and the last one for volume difference evaluation. The best results were achieved by the application of the precipitation fields gotten by ISD, Brandes with high limitation, Radar and Costa methods. For these methods, the calibration process compensated the differences on the precipitation fields. The differences observed in the precipitation fields had been reproduced in the hydrograms. The hydrograms of the radar data applications had not well reproduced the recession curve, and the hydrograms of the precipitation fields based only on rain gauges presented high peaks. Sometimes the composed techniques attenuate the peaks, however, sometimes they intensify them. More research is recommended to develop compoud methods that explore the advantages of the two equipments for rain measure
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Paudel, Murari. "An Examination of Distributed Hydrologic Modeling Methods as Compared with Traditional Lumped Parameter Approaches." BYU ScholarsArchive, 2010. https://scholarsarchive.byu.edu/etd/2219.
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Empirically based lumped hydrologic models have an extensive track record of use where as physically based, multi-dimensional distributed models are evolving for various engineering applications. Despite the availability of high resolution data, better computational resources and robust numerical methods, the usage of distributed models is still limited. The purpose of this research is to establish the credibility and usability of distributed hydrologic modeling tools of the United States Army Corps of Engineers (USACE) in order to promote the extended use of distributed models. Two of the USACE models were used as the modeling tools for the study, with Gridded Surface and Subsurface Hydrologic Analysis (GSSHA) representing a distributed and with Hydrologic Engineering Center-Hydrologic Modeling System (HEC-HMS) representing a lumped model. Watershed Modeling System (WMS) was used as the pre- and post-processing tool. The credibility of distributed models has been established by validating that the distributed models are efficient in solving complex hydrologic problems. The distributed and lumped models in HEC-HMS were compared. Similarly, the capabilities of GSSHA and lumped models in HEC-HMS in simulating land use change scenario were compared. The results of these studies were published in peer-reviewed journals. Similarly, the usability of the distributed models was studied taking GSSHA-WMS modeling as a test case. Some of the major issues in GSSHA-modeling using WMS interface were investigated and solutions were proposed to solve such issues. Personal experience with GSSHA and feedback from the students in a graduate class (CE531) and from participants in the USACE GSSHA training course were used to identify such roadblocks. The project being partly funded by the USACE Engineering Research and Development Center (ERDC) and partly by Aquaveo LLC, the research was motivated in improving GSSHA modeling using the WMS interface.
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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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Thanapakpawin, Porranee. "Spatially-distributed modeling of hydrology and nitrogen export from watersheds /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/9850.
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Santos, Franciane Mendonça dos. "Modelagem concentrada e semi-distribuída para simulação de vazão, produção de sedimentos e de contaminantes em bacias hidrográficas do interior de São Paulo." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/18/18139/tde-26112018-145857/.
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A escassez de dados hidrológicos no Brasil é um problema recorrente em muitas regiões, principalmente em se tratando de dados hidrométricos, produção de sedimentos e qualidade da água. A pesquisa por modelos de bacias hidrográficas tem aumentado nas últimas décadas, porém, a estimativa de dados hidrossedimentológicos a partir de modelos mais sofisticados demanda de grande número de variáveis, que devem ser ajustadas para cada sistema natural, o que dificulta a sua aplicação. O objetivo principal desta tese foi avaliar diferentes ferramentas de modelagem utilizadas para a estimativa da vazão, produção de sedimentos e qualidade da água e, em particular, comparar os resultados obtidos de um modelo hidrológico físico semi-distribuído, o Soil Water Assessment Tool (SWAT) com os resultados obtidos a partir de modelos hidrológicos concentrados, com base na metodologia do número da curva de escoamento do Soil Conservation Service (SCS-CN) e no modelo Generalized Watershed Loading Function (GWLF). Buscou-se avaliar e apresentar em quais condições o uso de cada modelo deve ser recomendado, ou seja, quando o esforço necessário para executar o modelo semi-distribuído leva a melhores resultados efetivos. Em relação à simulação da vazão, os resultados dos dois modelos foram altamente influenciados pelos dados de precipitação, indicando que existem, possivelmente, falhas ou erros de medição que poderiam ter influenciado negativamente os resultados. Portanto, foi proposto aplicar o modelo semi-distribuído com dados de precipitação interpolados (DPI) de alta resolução para verificar a eficiência de seus resultados em comparação com os resultados obtidos com a utilização dos dados de precipitação observados (DPO). Para simulação da produção de sedimentos, e das concentrações de nitrogênio e fósforo, o SWAT realiza uma simulação hidrológica mais detalhada, portanto, fornece resultados ligeiramente melhores para parâmetros de qualidade da água. O uso do modelo semi-distribuído também foi ampliado para simular uma bacia hidrográfica sob a influência do reservatório, a fim de verificar a potencialidade do modelo para esse propósito. Os modelos também foram aplicados para identificar quais os impactos potenciais das mudanças no uso do solo previstas e em andamento. Os cenários estudados foram: I – cenário atual, II – cenário tendencial, com o aumento da mancha urbana e substituição do solo exposto e de parte da mata nativa por uso agrícola; III – cenário desejável, complementa o crescimento urbano tendencial com aumento de áreas de reflorestamento. As metodologias foram aplicadas em duas bacias hidrográficas localizadas no Sudeste do Brasil. A primeira é a bacia do rio Jacaré-Guaçu, incluída na Unidade de Gerenciamento de Recursos Hídricos 13 (UGRHI-13), a montante da confluência do rio das Cruzes, com uma área de 1934 km2. O segundo caso de estudo, é a bacia do rio Atibaia, inserida na UGRHI-5, tem uma área de 2817,88 km2 e abrange municípios dos estados de São Paulo e Minas Gerais. Como principal conclusão, o desempenho do modelo semi-distribuído para estimar a produção de sedimentos, e as concentrações de nitrogênio e fósforo foi ligeiramente melhor do que as simulações do modelo concentrado SCS-CN e GWLF, mas essa vantagem pode não compensar o esforço adicional de calibrá-lo e validá-lo.The lack of hydrological data in Brazil is a recurrent problem in many regions, especially in hydrometric data, sediment yield and water quality. The research by simplified models has increased in the last decades, however, the estimation of hydrossedimentological data from these more sophisticated models demands many variables, which must be adjusted for each natural system, which makes it difficult to apply. At times it is necessary to respond quickly without much precision in the results, in these situations, simpler models with few parameters can be the solution. The objective of this research is to evaluate different modelling tools used estimate streamflow, sediments yield and nutrients loads values, and namely to compare the results obtained from a physically-based distributed hydrological model (SWAT) with the results from a lumped hydrological, the Soil Conservation Service (SCS-CN) and the Generalized Watershed Loading Function (GWLF) model. Both models use the curve number (CN) concept, determined from land use, soil hydrologic group and antecedent soil moisture conditions and were run with a daily time step. We are particularly interested in understanding under which conditions the use of each model is to be recommended, namely when does the addition effort required to run the distributed model leads to effective better results. The input variables and parameters of the lumped model are assumed constant throughout the watershed, while the SWAT model performs the hydrological analysis at a small unit level, designated as hydrological response units (HRUs), and integrates the results at a sub-basin level. In relation to the flow simulation, the results of the two models were highly influenced by the rainfall data, indicating that, possibly, faults or measurement errors could have negatively influenced the results. Therefore, it was proposed to apply the distributed model with high-resolution grids of daily precipitation to verify the efficiency of its results when compared to rainfall data. For simulation of sediment, nitrogen and phosphorus, SWAT performs a more detailed simulation and thus provides slightly better results. The use of the SWAT was also extended to simulate the influence of reservoir, in order to verify the potentiality of the model, in relation to the simulation. The models also were used to identify which are potential impacts of the ongoing land use changes. The scenarios were: I - Current scenario, II - trend scenario, with the increase of urban land and replacement of the exposed soil and part of the native forest by agricultural use; III - desirable scenario complements the trend urban growth with the replacement of exposed soil and part of the agricultural use by reforestation. The methodologies were applied on two watersheds located in the Southeast of Brazil. The first one is the Jacaré-Guaçu river basin, included in the Water Resources Management Unit 13 (UGRHI-13), upstream of Cruzes river confluence, with an area of 1934 km2. The second watershed is the Atibaia River Basin, a part of Water Resources Management Unit 5 (UGRHI-5). It has an area of 2817.88 km2 and covers municipalities of the states of São Paulo and Minas Gerais.
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Kilgore, Jennifer Leigh. "Development and Evaluation of a Gis-Based Spatially Distributed Unit Hydrograph Model." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/35777.
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Synthetic unit hydrographs, which assume uniform rainfall excess distribution and static watershed conditions, are frequently used to estimate hydrograph characteristics when observed data are unavailable. The objective of this research was to develop a spatially distributed unit hydrograph (SDUH) model that directly reflects spatial variation in the watershed in generating runoff hydrographs. The SDUH model is a time-area unit hydrograph technique that uses a geographic information system (GIS) to develop a cumulative travel time map of the watershed based on cell by cell estimates of overland and channel flow velocities. The model considers slope, land use, watershed position, channel characteristics, and rainfall excess intensity in determining flow velocities. The cumulative travel time map is divided into isochrones which are used to generate a time-area curve and the resulting unit hydrograph.
Predictions of the SDUH model along with the Snyder, SCS, and Clark synthetic unit hydrographs were compared with forty observed storm events from an 1153-ha Virginia Piedmont watershed. The SDUH model predictions were comparable or slightly better than those from the other models, with the lowest relative error in the peak flow rate prediction for 12 of the 40 storms, and a model efficiency of at least 0.90 for 21 of the storms. Despite the good predictions of the hydrograph peak flow rate and shape, the time to peak was underpredicted for 34 of the 40 storms.
Runoff from the 40 storms was also generated for two subwatersheds (C: 462 ha; D: 328 ha) in Owl Run to assess the effect of scale on the SDUH model. Peak flow rate predictions were more accurate for the entire watershed than for either subwatershed. The time to peak prediction and model efficiency statistics were comparable for the entire watershed and subwatershed D. Subwatershed C had poorer predictions, which were attributed to a large pond in the main channel, rather than to scale effects.
The SDUH model provides a framework for predicting runoff hydrographs for ungauged watersheds that can reflect the spatially distributed nature of the rainfall-runoff process. Predictions were comparable to the other synthetic unit hydrograph techniques. Because the time to peak and model efficiency statistics were similar for the 1153-ha watershed and a 328-ha subwatershed, scale does not have a major impact on the accuracy of the SDUH model.
Master of Science
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Narasimhan, Balaji. "Development of indices for agricultural drought monitoring using a spatially distributed hydrologic model." Diss., Texas A&M University, 2004. http://hdl.handle.net/1969.1/2727.
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Farming communities in the United States and around the world lose billions of dollars every year due to drought. Drought Indices such as the Palmer Drought Severity Index (PDSI) and Standardized Precipitation Index (SPI) are widely used by the government agencies to assess and respond to drought. These drought indices are currently monitored at a large spatial resolution (several thousand km2). Further, these drought indices are primarily based on precipitation deficits and are thus good indicators for monitoring large scale meteorological drought. However, agricultural drought depends on soil moisture and evapotranspiration deficits. Hence, two drought indices, the Evapotranspiration Deficit Index (ETDI) and Soil Moisture Deficit Index (SMDI), were developed in this study based on evapotranspiration and soil moisture deficits, respectively. A Geographical Information System (GIS) based approach was used to simulate the hydrology using soil and land use properties at a much finer spatial resolution (16km2) than the existing drought indices. The Soil and Water Assessment Tool (SWAT) was used to simulate the long-term hydrology of six watersheds located in various climatic zones of Texas. The simulated soil water was well-correlated with the Normalized Difference Vegetation Index NDVI (r ~ 0.6) for agriculture and pasture land use types, indicating that the model performed well in simulating the soil water. Using historical weather data from 1901-2002, long-term weekly normal soil moisture and evapotranspiration were estimated. This long-term weekly normal soil moisture and evapotranspiration data was used to calculate ETDI and SMDI at a spatial resolution of 4km ?? 4km. Analysis of the data showed that ETDI and SMDI compared well with wheat and sorghum yields (r > 0.75) suggesting that they are good indicators of agricultural drought. Rainfall is a highly variable input both spatially and temporally. Hence, the use of NEXRAD rainfall data was studied for simulating soil moisture and drought. Analysis of the data showed that raingages often miss small rainfall events that introduce considerable spatial variability among soil moisture simulated using raingage and NEXRAD rainfall data, especially during drought conditions. The study showed that the use of NEXRAD data could improve drought monitoring at a much better spatial resolution.
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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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Kim, Sunmin. "Stochastic Real-Time Flood Forecasting Using Weather Radar and a Distributed Hydrologic Model." 京都大学 (Kyoto University), 2006. http://hdl.handle.net/2433/123488.
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Della, Libera Zanchetta Andre. "IFIS model-plus: a web-based GUI for visualization, comparison and evaluation of distributed hydrologic model outputs." Thesis, University of Iowa, 2017. https://ir.uiowa.edu/etd/5455.
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This work explores the use of hydroinformatics tools to provide a user friendly and accessible interface for executing and visualizing the output of distributed hydrological models for Iowa. It uses an IFIS-based web environment for graphical displays and it communicates with the ASYNCH ODE solver to provide input parameters and to gather modeling outputs. The distributed hydrologic models used here are based on the segmentation of the terrain into hillslope-link hydrologic units, for which water flow processes are represented by sets of nonlinear ordinary differential equations. This modeling strategy has shown promising results in in modeling extreme flood events in the state of Iowa – USA. The usage and evaluation of outputs from hillslope-link models (HLM) has been limited to a restrict group of academics due to the demand of high processing capability and the number of customized tools needed to visualize model outputs. HLM-based models provide abundant output information on rainfall-runoff processes of the hydrological cycle, including estimates of discharge for all streams in the state of Iowa, and for all conceptual vertical layers of water storage in soils.
The interfaces and methodologies developed in this thesis respond to the constant demand for communicating effectively water-related information from academic communities to the public using hydroinformatics tools to provide an accessible portal to the information generated by complex hydrological models. It also facilitates model development and evaluation by allowing rapid development of what-if scenarios. This work represents a significant advance in this direction, and the results have been made publicly available online under the URL http://ifis.iowafloodcenter.org/ifis/sc/modelplus/.
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Bari, Mohammed A. "A distributed conceptual model for stream salinity generation processes : a systematic data-based approach /." Connect to this title, 2005. http://theses.library.uwa.edu.au/adt-WU2006.0058.
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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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Fisher, James I. "The use of remote sensing and other system state estimates in the calibration of a distributed hydrological model." Thesis, Lancaster University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307699.
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Stonesifer, Crystal S. "Modeling the Cumulative Effects of Forest Fire on Watershed Hydrology: A Post-fire Application of the Distributed Hydrology-Soil-Vegetation Model (DHSVM)." The University of Montana, 2007. http://etd.lib.umt.edu/theses/available/etd-05222007-143739/.
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The Distributed Hydrology-Soil-Vegetation Model (DHSVM) was applied to the Eightmile Creek watershed in western Montana. The purpose of this research was primarily to assess the applicability of the model as a cumulative effects assessment tool in the post-fire landscape of a forested watershed in this region. The model was first calibrated to the pre-fire watershed conditions using six years of historic streamflow data. DHSVM was able to accurately simulate the general shape of the measured hydrograph for each of the six simulated water years, and the normalized median absolute error statistics were below the target threshold of 50% for each year simulated. This relative success of the calibration efforts is particularly surprising when one considers the significant limitations presented by the lack of any sub-daily or high-elevation meteorological data for use in driving the calibration simulations. Because the accuracy of DHSVM simulations were greatly improved through rigorous calibration, this research demonstrates the need for model calibration to a watershed of interest, prior to hydrologic simulations of different landscape scenarios. Next, two different calibrated versions of DHSVM, including DHSVM version 2.0.1 and the DHSVM fire model, were each used to simulate runoff in the Eightmile Creek watershed following a near catchment-wide stand-replacing forest fire. Due to weather anomalies and limited, discontinuous streamflow data, no decisive conclusions could be made regarding the performance of either version of the model in the validation efforts. Results do suggest, though, that the DHSVM fire model has the potential to outperform the standard model version in fire-affected landscapes. Further research utilizing the DHSVM fire model with more substantial post-fire streamflow records for model validation is warranted.
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Dolder, Herman Guillermo. "A Method for Using Pre-Computed Scenarios of Physically-Based Spatially-Distributed Hydrologic Models in Flood Forecasting Systems." BYU ScholarsArchive, 2015. https://scholarsarchive.byu.edu/etd/5676.
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Every year floods are responsible of a significant number of human losses, many of which could be avoided with a broader implementation of flood forecasting systems. Nevertheless, there are still some technological and economic limitations that impede the creation of these systems in many parts of the world. At the core of many flood forecasting systems is a hydrologic model that transforms the weather forecast into a flow forecast. Using real-time modeling for potential floods poses a series of problems: if the model is complex, the computational power required can be significant, and consequently expensive, and if the model is simple enough to run on regular computers in the time allotted, it is likely that the results will not be accurate enough to be useful. I propose the development of a standardized method for using pre-computed scenarios as an alternative to real-time flood modeling. I explain how pre-computing has been used on other realms in the past, and how it is beginning to be implemented in different branches of hydrology, the prediction coastal flooding due to storms or tsunamis being one of the most developed. My research has focused on answering the questions that arise during the design stage of a flood forecasting system not only for rain or snow driven floods, but also by anthropogenic-produced floods. I analyze the number of parameters and their granularity to be used to create the scenarios, the accuracy of the results, different strategies to implement the systems, etc. Finally, I present some test-cases of the application of the method, and assess their results.
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Westerberg, Ida. "Utveckling och tillämpning av en GIS-baserad hydrologisk modell." Thesis, Uppsala University, Department of Earth Sciences, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-88880.
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A distributed hydrological rainfall-runoff model has been developed using a GIS integrated with a dynamic programming module (PCRaster). The model has been developed within the framework of the EU-project TWINBAS at IVL Swedish Environmental Research Institute, and is intended for use in WATSHMAN – a tool for watershed management developed at IVL. The model simulates runoff from a catchment based on daily mean values of temperature and precipitation. The GIS input data consist of maps with soil type, land-use, lakes, rivers and a digital elevation model. The model is a hybrid between a conceptual and a physical model. The snow routine uses the degree-day method, the evapotranspiration routine uses the Blainey-Criddle equation, the infiltration routine is based on Green-Ampt, groundwater is modelled assuming a linear reservoir and the flow routing is done with the kinematic wave equation combined with Manning’s equation.
The GIS and the hydrologic model are embedded in one another, allowing calculation of each parameter in each grid cell. The output from the model consists of raster maps for each time step for a pre-defined parameter, or a time series for a parameter at a specified grid cell. The flow network is generated from the digital elevation model and determines the water flow on the grid scale. The smallest possible grid size is thus obtained from the resolution of the digital elevation model. In this implementation the grid size was 50 m x 50 m. The raster structure of the model allows for easy use of data from climate models or remotely sensed data.
The model was evaluated using the River Kölstaån catchment, a part (110 km2) of the Lake Mälaren catchment, which has its outflow in central Stockholm, Sweden. The integration of the GIS and the hydrologic model worked well, giving significant advantages with respect to taking lakes and land-use into account. The evaluation data consisted of observed run-off for the period 1981 to 1991. The result from the calibration period shows a great variation in Reff (Nash & Sutcliffe) between the years, the three best years having Reff-values of 0.70 – 0.80. The Reff-value for the entire calibration period was 0.55 and 0.48 for the validation period, where again there was great variation between different years. The volume error was 0.1 % for the calibration period and -21 % for the validation period. The evapotranspiration was overestimated during the validation period, which is probably a result of excess rain during the calibration period. The results are promising and the model has many advantages – especially the integrated GIS-system – compared to the present WATSHMAN model. It could be further developed by introducing a second groundwater storage and refining the evapotranspiration and infiltration routine. Given the promising results, the model should be evaluated in other larger and hillier areas and preferably against more distributed data.
En helt distribuerad GIS-baserad hydrologisk modell för modellering i avrinningsområden på lokal/regional skala har byggts upp i PCRaster. Arbetet utfördes på IVL Svenska Miljöinstitutet AB inom ramen för EU-projektet TWINBAS, som har som mål att identifiera kunskapsluckor inför implementeringen av EU:s ramdirektiv för vatten. Modellen är tänkt att användas i WATSHMAN (Watershed Management System), IVLs verktyg för vattenplanering i avrinningsområden där bland annat källfördelningsberäkningar och åtgärdsanalyser ingår. Den uppbyggda modellen är en hybrid mellan en fysikalisk och en konceptuell hydrologisk modell och predikterar vattenföring på pixelnivå i avrinningsområden. Simuleringen drivs av dygnsmedelvärden för temperatur och nederbörd och modellen tar hänsyn till markanvändning, jordart, topografi och sjöar. De modellekvationer som används är grad-dagsmetoden för snö, Blainey-Criddle för evapotranspiration, Green-Ampt för infiltration, linjärt magasin för grundvatten och Mannings ekvation för flödesrouting.
Det geografiska informationssystemet och den hydrologiska modellen är helt integrerade, vilket gör att alla parametervärden beräknas för varje enskild pixel. Som utdata ger modellen en rasterkarta för varje tidssteg för en i förväg bestämd parameter, eller tidsserier över parametervärden i definierade punkter. Vattnet transporteras i ett utifrån höjdmodellen genererat flödesnätverk och vattnets flödesväg bestäms därmed på pixelnivå. Minsta möjliga pixelstorlek bestäms således utifrån höjdmodellens upplösning, och var vid denna tillämpning 50 m gånger 50 m. Modellens uppbyggnad med raster gör det enkelt att använda data från klimatmodeller eller fjärranalys.
Avrinningsområdet för Kölstaån, ett biflöde till Köpingsån i Mälardalen, har använts för att utvärdera modellen. Integreringen av GIS och hydrologisk modell fungerade mycket väl och gav stora fördelar t ex vad gäller att ta hänsyn till sjöar och markanvändning. Modellen kalibrerades med data från åren 1981 till 1986 och det erhållna volymfelet var då 0,1 % och Reff-värdet (Nash & Sutcliffe) 0,55. Stora variationer erhölls dock mellan åren; för de tre bästa åren låg Reff-värdet mellan 0,70 och 0,80. Ett mycket kraftigt nederbördstillfälle samt regleringar i huvudfåran av vattendraget ligger troligtvis bakom de mindre väl beskrivna åren. Även under valideringsperioden (1987 till 1991) fungerade modellen väl, så när som på att avdunstningen överskattades på vårarna (antagligen beroende av det stora regnet under kalibreringen), och Reff-värde och volymfel hamnade på 0,48 respektive -21 %, även här med stora variationer mellan åren. Resultaten är lovande och modellen har många fördelar jämfört med den nuvarande WATSHMAN-modellen. Den skulle kunna förbättras ytterligare genom att dela upp grundvattnet i två magasin samt förfina evapotranspirations- och infiltrationsrutinerna. Den höjdmodellsbaserade modellen bör utvärderas även i andra mer kuperade områden samt mot mer distibuerade data.
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Richard, Bastien. "Coupling agent-based and agro-hydrological modeling to represent human actions within an agro-hydrosystem. Application to collective irrigation in the Buëch catchment (France)." Thesis, Paris, Institut agronomique, vétérinaire et forestier de France, 2020. http://www.theses.fr/2020IAVF0023.
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Dans un contexte de changement global, la gestion de la ressource en eau, entre acteurs aux objectifs parfois conflictuels, doit être revisitée. Des outils de modélisation et de simulation, destinés à la conduite d'analyses prospectives, sont actuellement développés à Irstea en partenariat avec les acteurs de la gestion de l'eau. Les processus hydrologiques sont relativement biens connus et des plateformes de modélisation et de simulation permettent de les simuler. Toutefois, avant de pouvoir produire des scénarios prospectifs pertinents, plusieurs améliorations sont nécessaires, notamment la prise en compte des rétroactions entre composantes physiques et sociales, pourtant déterminantes sur la quantification des usages de l'eau. La modélisation hydrologique distribuée permet de simuler les dynamiques hydrologiques d'un bassin versant en intégrant l'hétérogénéité spatiale du bassin et donc en permettant d'imaginer des boucles de rétroactions locales liées à l'activité anthropique. L'objectif de la thèse est de coupler un modèle hydrologique distribué existant à un modèle agent à construire, représentant les dynamiques sociales et pilotant les rétroactions locales liées à l'activité anthropique. Pour construire ce modèle agent, nous proposons d'utiliser la théorie de l'action située (qui donne un cadre pour décrire les actions et les décisions individuelles en se basant sur le concept d'affordance) et le concept de stigmergie (qui permet de décrire les interactions indirectes entre acteurs). Dans ce cadre, la représentation de la prise de décision d'un ou plusieurs agents se base sur la définition de l'ensemble d'actions pouvant être réalisées à un moment donné. Ceci implique de se focaliser sur les variables d'intérêt de l'agent (variables perçues et variables de contrôle, y compris les variables hydrologiques) qui sont le plus souvent locales. Ainsi, l'exercice de couplage entre le modèle agent et le modèle d'hydrologie distribué consistera en grande partie à définir ces variables d'intérêts des agents et à les relier aux variables d'états ou aux sorties du modèle hydrologique distribué. Cette liaison permettra de spécifier les rétroactions locales liées aux activités humaines mais aussi de disposer de sorties de simulation spatialisées correspondant à des variables d'intérêts pour les acteurs. Dans le cadre de cette thèse, nous nous limiterons aux secteurs d'activités principaux de deux bassins versants représentatifs de la Durance. Nous analyserons au fur et à mesure l'impact des rétroactions locales implémentées sur les sorties calculées à l'échelle du bassin. L'objectif est d'obtenir un modèle couplé, calibré sur les deux-sous bassins, que l'on puisse utiliser pour discuter des impacts des stratégies d'adaptations locales (principalement du secteur de l'irrigation qui constitue la plus grande demande en eau sur le bassin) sur le comportement global du système sous contrainte de stratégies définies à l'échelle du bassin (subventions, réglementations,...)In a context of global change, management of water resources between actors with sometimes conflicting objectives should be revisited. Modeling and simulation tools, dedicated to prospective analysis, are being developed at Irstea, in partnership with stakehoders of water management. Hydrological processes are rather well know and modeling and simulation platforms are available for their simulation. However, before they can produce relevant prospective scenarios, several improvments are required, in particular accounting for feedbacks loops between social and physical dynamics. Distributed hydrological modeling enables the simulation of hydrological dynamics considering spatial heterogeneity of the catchments and consequently gives the opportunity to imagine local feedback loops related to human activites. The objectives of the thesis is to couple an existing distributed hydrological model to an agent based model representing social dynamics and driving the local feedback loops related to human activities. We propose to use the theory of situed action (providing a framework to describe individual actions and decisions) and the concept of stigmergy (providing a framework to describe indirect interactions amongst actors) to build the agent based model. In this context, the decision making process of one or several agents is based on the set of actions that he can possibly realize at each moment. this implies to put the focus on the variables of interest of the agent (perceived variables and control variables, including hydrological variables) that are most of the time local variables. Hence, the exercice of coupling the agent model and the hydrological model will consist mainly in defining agents's variables of interest and to relate them to state variables or outputs of the hydrological model. This link will enable to specify local feedback loops related to human activities and furthermore to get spatial simulation outputs matching stakeholders' variables of interest. The scope of the PhD thesis is limited to the main sectors of activity of the two chosen sub-catchments of the Durance river. We will iteratively measure the impact of the implemented local feedback loops on the outputs computed at the scale of the sub-catchment. The impacts of local and sectoral adaptations (mainly from the irrigated agriculture sector constituting the main water use), on the global behavior oh the hydrosystem, under constraints of management strategies specified at the scale of the sub-catchment (incentives, regulations,..)
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Wichakul, Supattana. "Development and applications of a distributed hydrological model for water resources assessment at the Chao Phraya River Basin under a changing climate." 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/192155.
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Yu, Zhongbo. "Development of a physically-based distributed-parameter watershed model (basin-scale hydrologic model) and its application to Big Darby Creek watershed, Ohio /." The Ohio State University, 1996. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487942739805592.
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Kamal, Sameer A. (Sameer Ahmed). "The use of a distributed hydrologic model to predict dynamic landslide susceptibility for a humid basin in Puerto Rico." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/55154.
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Thesis (Env. E.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2009."September 2009." Cataloged from PDF version of thesis.
Includes bibliographical references (p. 86-91).
This thesis describes the use of a distributed hydrology model in conjunction with a Factor of Safety (FS) algorithm to predict dynamic landslide susceptibility for a humid basin in Puerto Rico. The Mameyes basin, located in the Luquillo Experimental Forest in Puerto Rico, was selected for modeling based on the rich ensemble of soil, vegetation, topographical, meteorological and historic landslide data available. The basin was parameterized into the TIN-based Real-time Integrated Basin Simulator (tRIBS) with particular emphasis on vegetation parameters for broadleaf evergreen trees in tropical climates. The basin was forced with precipitation data that included a synthesized rainfall event likely to result in a landslide based on rainfall intensity-duration thresholds. The basin's response was assessed mainly in terms of soil moisture and values of selected vegetation parameters, which served as the dynamic inputs into the FS algorithm.
(cont.) An off-line FS algorithm was developed and tested using typical values for parameters encountered in the Mameyes basin. Sensitivity analyses indicated that slope angle, soil cohesion and soil moisture were the most sensitive parameters in this FS algorithm. When the tRIBS / FS Algorithm combination was employed over the entire basin, landslides were indicated in 48 out of 13,169 modeled locations. The spatial distribution of landslides compared favorably to a static landslide susceptibility map developed in previous work by Lepore et al. (2008b) while the temporal distribution of landslides was correlated with rainfall events. Landslides were predicted over a range of slope angle values, including on relatively gentle slopes where the modeled soil moisture drove the instability. The results demonstrate that the tRIBS/FS algorithm combination developed in this work is able to capture the key dynamics associated with slope stability, specifically the interactions between the slope angle and the soil moisture state.
by Sameer A. Kamal.
Env.E.
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Graves, David. "An Assessment of the Impacts of Climate Change on the Upper Clackamas River Basin with a Distributed Hydrologic Model." PDXScholar, 2005. https://pdxscholar.library.pdx.edu/open_access_etds/2432.
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The Pacific Northwest is dependent on seasonal snowmelt for water resources that support a significant portion of its economy. Increased temperatures resulting from higher concentrations of atmospheric greenhouse gases may cause disruptions to these resources because of reductions in the annual snowpack and variations of the timing of snowmelt. This study reconstructs and applies a GIS-based distributed hydrologic model at a monthly scale to assess the effects of future climate change on runoff from the Upper Clackamas River Basin (located near Portland, Oregon). Historic flow data and snow measurements are used to calibrate and test the perfonnance of the hydro logic model for a contemporary period (1971-2000), and the model is run for two future scenarios (2010-2039 and 2070-2099) using IS92 climate change scenarios from two global climate circulation models (Hadley and Canadian Centre for Climate) as inputs.
The results forecast that mean peak snowpack in the study area will drop dramatically (36% to 49% by 2010-2039, and 83% to 88% by 2070-2099), resulting in earlier runoff and diminished spring and summer flows. Increases to mean winter runoff by by the 2070-2099 period vary from moderate (13.7%) to large (46.4%), depending on the changes to precipitation forecasted by the global climate circulation models. These results are similar to those of other studies in areas dependent on snowpack for seasonal runoff, but the reductions to snowpack are more severe in this study than similar studies for the entire Columbia Basin, presumably because the elevations of much of the Upper Clackamas Basin are near the current mid-winter snow line.
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Adamovic, Marko. "Development of a data-driven distributed hydrological model for regional scale catchments prone to Mediterranean flash floods. Application to the Ardèche catchment, France." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENU039/document.
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L'objectif scientifique de la thèse est de progresser dans la modélisation hydrologique spatiale régionale dans le contexte de crues éclairs qui représentent l'une des catastrophes naturelles les plus destructrices dans la région Méditerranéenne. L'accent est mis sur les questions de mise à l'échelle des bassins versants et la dérivation des équations et des modèles applicables aux bassins de milieu simplifiées de grande taille pour mieux décrire l'hétérogénéité du paysage et de la complexité du processus. Telles sont les questions clés pour faciliter le modèle mis en place dans le contexte de l'ensemble du bassin versant et d'essayer son application dans les bassins non jaugés trop. Pour répondre à ces questions, une modélisation hydrologique spatiale simplifiée sur les sous-bassins versants est d'abord proposé où les paramètres sont essentiellement tirées de l'information disponible (surtout cartographique). La méthode de Kirchner (WRR, 2009) qui suppose que le débit à la sortie est la seule fonction de stockage du bassin versant, est spécifiquement étudiée dans le cadre des bassins versants Méditerranéens. L'étape suivante consiste à créer un nouveau modèle hydrologique SIMPLEFLOOD distribué sur la base de « top down » méthodologie de Kirchner dans la plateforme de modélisation JAMS. Les paramètres du modèle simple sont estimés à des endroits calibrés et une régionalisation se fait en fonction de la géologie. Le bassin versant est discrétisé en sous-bassins versants d'environ 10 km2. La dernière étape consiste à procéder à un couplage de données avec le modèle hydraulique MAGE 1D développé à IRSTEA HHLY tenir compte des effets de propagation de la rivière sur les hydrogrammes simulés. Le couplage est externe, ce qui signifie que les sorties du modèle hydrologique dans le système de modélisation de JAMS deviennent les entrées du modèle MAGE hydraulique. Les sorties sont les débits qui sont transférés dans le modèle de MAGE soit comme flux latéraux (provenant des terres adjacentes) et /ou entrées d'eau locales. L'application de la thèse est le bassin versant de l'Ardèche (2388 km ²), qui est l'un des sites pilotes français pour le programme international HyMeX (cycle hydrologique dans l'expérience de la Méditerranée, http://www.hymex.org/). La thèse proposée contribue également au projet FloodScale (multi-échelle d'observation hydrométéorologique et de modélisation pour la compréhension et simulation des crues éclairs (http://floodscale.irstea.fr/). L'application de la méthodologie Kirchner (2009) montre que les résultats de simulation des débits sont bonnes pour les bassins de granit, trouvés à être caractérisée principalement par des processus excès de ruissellement et d'écoulement sous la surface de saturation. L'hypothèse simple de système dynamique fonctionne particulièrement bien dans des conditions humides (pics et les récessions sont bien modélisés). D'autre part, la performance du modèle est moins bien représentée à l'été et les périodes de sécheresse où l'évapotranspiration est large et observations de bas-débits sont inexactes. Dans le bassin versant de l'Ardèche, les précipitations simulées correspondent bien à de stations de jaugeage observés et données de réanalyse SAFRAN pendant les périodes de non-végétation. Le modèle doit encore être amélioré pour inclure une représentation plus précise de l'évapotranspiration réelle, mais fournit un résumé satisfaisant du fonctionnement du bassin versant pendant les périodes humides et d'hiver. Le couplage du modèle hydrologique obtenue avec le modèle hydraulique MAGE 1D fournit des résultats satisfaisants mais les résultats sont si réciproques comme dans le cas du modèle hydrologique ou une équation d'onde cinématique simple pour le routage des flux existe. On peut dire que dans les situations ou débordement de la rivière est significative, le couplage serai crucialThe scientific objective of the thesis is to progress in regional spatial hydrological modeling in the context of flash floods that represent one of the most destructive natural hazards in the Mediterranean region. Emphasis is put on catchment scaling issues and derivation of simplified equations and models applicable to basins of medium to large size to best describe landscape heterogeneity and process complexity. These are the key issues in facilitating the model set up in the context of the whole catchment and trying its application in ungauged catchments too. To address these issues, a simplified spatial hydrological modeling over sub-catchments is first proposed where parameters are essentially derived from available information (cartographic utmost). For this purpose, the Kirchner (WRR, 2009) method that assumes that discharge at the outlet is only a function of catchment storage is specifically studied in the context of Mediterranean catchments. The next step is to create a new distributed hydrological model based on the data driven methodology of Kirchner within the JAMS modeling framework. The parameters of the simple model are estimated at the gauged locations and a regionalization is done according to geology. The catchment is discretized into sub-catchments of about 10 km2. The final step is to proceed with data coupling with the MAGE 1D hydraulic model developed at HHLY to consider river propagation effects on the simulated hydrographs. The coupling is external, meaning that outputs from the hydrological model in JAMS modeling system become inputs to the hydraulic model MAGE. Outputs are discharge rates in the reach network that are transferred into the MAGE model as either lateral flows (coming from adjacent land) and/or local inflows. The case study of the thesis is the Ardèche catchment (2388 km²), which is one of the French pilot sites for the HyMeX international program (Hydrological Cycle in the Mediterranean Experiment, http://www.hymex.org/). The proposed thesis also contributes to the FloodScale project (Multi-scale hydrometeorological observation and modeling for flash floods understanding and simulation, http://floodscale.irstea.fr/ ). The application of the Kirchner (2009) methodology shows that resulting discharge simulation results are good for granite catchments, found to be predominantly characterized by saturation excess runoff and sub-surface flow processes. The simple dynamical system hypothesis works especially well in wet conditions (peaks and recessions are well modeled). On the other hand, poor model performance is associated with summer and dry periods when evapotranspiration is high and operational low-flow discharge observations are inaccurate. In the Ardèche catchment, inferred precipitation rates agree well in timing and amount with observed gauging stations and SAFRAN data reanalysis during the non-vegetation periods. The model should further be improved to include a more accurate representation of actual evapotranspiration, but provides a satisfying summary of the catchment functioning during wet and winter periods. The coupling of the resulting hydrological model with the MAGE 1D hydraulic model provides satisfying results. However, the results show that the timing and magnitude of simulated discharge with coupled model is as good as by the hydrological model with a simple kinematic wave equation for flow routing. We argue that in situations when there is a significant overflow in the floodplain the interest of the coupling with the hydraulic model becomes crucial
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Shurtz, Kayson M. "Automated Calibration of the GSSHA Watershed Model: A Look at Accuracy and Viability for Routine Hydrologic Modeling." Diss., CLICK HERE for online access, 2009. http://contentdm.lib.byu.edu/ETD/image/etd3262.pdf.
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Sun, Jingyun. "Hydrologic and hydraulic model development for flood mitigation and routing method comparison in Soap Creek Watershed, Iowa." Thesis, University of Iowa, 2015. https://ir.uiowa.edu/etd/1914.
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The primary objective of this thesis is to develop hydrologic and hydraulic models for the Soap Creek Watershed, IA for the evaluation of alternative flood mitigation strategies and the analysis of the differences between hydrologic and hydraulic routing methods.
In 2008, the state of Iowa suffered a disastrous flood that caused extensive damage to homes, agricultural lands, commercial property, and public infrastructures. To reduce the flood damage across Iowa, the U.S. Department of Housing and Urban Development (HUD) awarded funds to the Iowa Flood Center and IIHR-Hydroscience &Engineering at the University of Iowa to conduct the Iowa Watersheds Project. The Soap Creek Watershed was selected as one of the study areas because this region has suffered frequent severe floods over the past century and because local landowners have organized to construct over 130 flood detention ponds within it since 1985.
As part of the Iowa Watersheds Project, we developed a hydrologic model using the
U.S. Army Corps of Engineers’ (USACE) Hydrologic Center’s hydrologic Modeling System (HEC-HMS). We used the hydrologic model to evaluate the effectiveness of the existing flood mitigation structures with respect to discharge and to identify the high runoff potential areas. We also investigated the potential impact of two additional flood mitigation practices within the Soap Creek Watershed by utilizing the hydrologic model, which includes changing the land use and improving the soil quality. The HEC-HMS model simulated 24-hour design storms with different return periods, including 10, 25, 50, and 100 year. The results from modeling four design storms revealed that all three practices can reduce the peak discharge at different levels. The existing detention ponds were shown to reduce the peak discharge by 28% to 40% depending on the choice of observed locations and design storms. However, changing the land use can reduce the peak discharge by an average of only 1.0 %, whereas improving the soil quality can result in an average of 15 % reduction.
Additionally, we designed a hydraulic model using the United States Army Corps of Engineers’ (USACE) Hydrologic Engineering Center’s River Analysis System (HEC- RAS) to perform a comparative evaluation of hydrologic and hydraulic routing methods. The hydrologic routing method employed in this study is the Muskingum Routing method. We compare the historical and design storms between HEC-HMS, HEC-RAS, and observed stage hydrographs and take the hydrograph timing, shape, and magnitude into account. Our results indicate that the hydraulic routing method simulates the hydrograph shape more effectively in this case.
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Silva, Michel Metran da. "Dinâmica espaço-temporal das áreas variáveis de afluência da bacia do córrego do Cavalheiro." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-10122012-084300/.
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As áreas variáveis de afluência (AVAs) são dinâmicas, apresentando expansão das áreas saturadas durante os eventos de chuva, geralmente próximas aos cursos d\'água e, no momento que a chuva cessa, estas áreas saturadas se contraem. O escoamento superficial ocorre nessas áreas devido ao excesso de saturação, provocado pelo aumento do volume d\'água armazenado no perfil de solo e, extravasamento nas áreas com solos rasos, próxima aos rios. Dessa forma, faz-se necessário quantificar o processo de escoamento superficial para a correta delimitação das AVAs. A utilização dos modelos hidrológicos para essa finalidade teve início após legislação estadunidense que define níveis máximos permitidos para poluição difusa. Diversos modelos foram desenvolvidos para quantificar a entrada de poluentes nos corpos hídricos, entretanto não havia maneira precisa de localizar as áreas variáveis de afluência, sendo estas as mais propensas a carrear os contaminantes. Somente através da utilização de modelos hidrológicos distribuídos foi possível considerar o componente espacial, ou seja, a localização exata da ocorrência dos processos hidrológicos, e sua inter-relação com uso de solo e tipo de solo, permitindo testar diferentes cenários avaliando quais áreas convertidas em florestas contribuiriam para maior ganho de serviços ecossistêmicos relacionados à manutenção de recursos hídricos. Portanto, foram modelados 3 cenários: o cenário atual, o cenário AVA e o cenário Código Florestal. O primeiro representa a situação atual do uso do solo, e fornece base para comparação com outros cenários. A probabilidade de saturação para este cenário foi definida com uso do modelo hidrológico GSSHA, permitindo delimitar as áreas variáveis de afluência e criar o cenário AVA, o qual simula a restauração florestal em todas as áreas variáveis de afluência. Por último, foi modelado o cenário Código Florestal, que simula a restauração florestal das áreas de preservação permanentes (APPs), com a função de avaliar quais os impactos para a manutenção dos recursos hídricos caso seja cumprido o Código Florestal (Lei nº. 4.711/65) e sejam restauradas todas as áreas de preservação permanente. Os resultados mostram que a restauração das AVA, com alteração de apenas 4,04% da área total da bacia, aumentaria em 48% a infiltração da água no solo, eliminando a geração de escoamento superficial em áreas agrosilvopastoris e conseqüente carreamento de poluentes provenientes dessas áreas. A restauração das APPs representa uma alteração de 9,36% da área da bacia e promove a recuperação da dinâmica de expansão e contração das nascentes da bacia hidrográfica, que garante redução da vazão e atraso do pico de vazão, evitando respostas hidrológicas hortonianas na bacia hidrográfica. Ambos cenários apresentam benefícios para manutenção dos recursos hídricos. As áreas de preservação permanente apresentam papel significativo na proteção dos recursos hídricos, protegendo mais de 60% das AVAs e sendo de fácil delimitação. A utilização do índice topográfico como variável substituta à modelagem hidrológica apresentou correlação de ~0,33, que permite utilizar o índice para uma análise exploratória, porém insuficiente para delimitar as áreas variáveis de afluência.The variables source areas (VSA) are dynamic, showing expansion of saturated areas during rain events, usually near to streams and, at the time the rain stops, these saturated areas contract. Runoff occurs in these areas due to saturation excess overland flow, caused by increased of stored volume water in the soil profile, and extravasation in areas with shallow soils, next to streams. Thus, it is necessary to quantify the process of runoff for the correct delineation of VSA. The use of hydrological models for this purpose began after U.S. law which sets maximum permitted levels for diffuse pollution. Several models have been developed to quantify the entry of pollutants in water bodies, however there was no accurate way to pinpoint variables source areas, which are the most likely to carrying contaminants. Only through the use of distributed hydrological models was possible to consider the spatial component, in other words, the exact location of the occurrence of hydrological processes and their interrelationship with land use and soil type, allowing you to test different scenarios by assessing which areas converted to forests contribute to greater gains in ecosystem services related to maintenance of water resources. Therefore, were evaluated three scenarios: the actual scenario, the VSA scenario and the Forest Code scenario. The first one represents the current state of land use and provides a basis for comparison with other scenarios. The probability of saturation for this scenario was defined using the hydrological model GSSHA, allowing to delimit variables source areas and to create the VSA scenario, which simulates forest restoration in all variables source areas. Finally, was modeled the Forestry Code scenario, which simulates forest restoration of permanent preservation areas (PPA), whose function is to assess the impacts for the maintenance of water resources if it complied the Forest Code (Law nº. 4.711/65) and restored all permanent preservation areas. The results show that the restoration of the VSA, with only a 4,04% change of the total area of the watershed, it would increase in 48% water infiltration into the soil, eliminating the generation of surface runoff and consequent carry pollutants from these areas. The restoration of the PPA represents a change of 9,36% of the watershed area and promotes the recovery of dynamic expansion and contraction of the headwaters of the watershed, which ensures reduction in flow rate and delay peak flow, avoiding answers hortonian in the hydrological basin. Both scenarios provide benefits for maintenance of water resources. The permanent preservation areas have significant role in protecting water resources, protecting more than 60% of VSA and being easy delimitation. The use of topographic index as surrogate parameter correlated to the hydrological modeling of ~ 0,33, which allows use the index to an exploratory analysis, but insufficient to delineate the variables source areas.
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Labbas, Mériem. "Modélisation hydrologique de bassins versants périurbains et influence de l'occupation du sol et de la gestion des eaux pluviales : Application au bassin de l'Yzeron (130km2)." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAU006/document.
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Les bassins périurbains, constitués de zones urbaines, agricoles et naturelles, sont des bassinsversants complexes à étudier. L’augmentation des surfaces imperméables et les modifications deschemins d’écoulement par les réseaux d’assainissement influencent leur hydrologie. Ces modificationssont notamment liées aux choix de modes de gestion des eaux pluviales : réseaux unitaires,réseaux séparatifs, infiltration à la parcelle, etc. La modélisation hydrologique spatialisée, quirend compte de l’hétérogénéité des bassins versants, est un outil permettant d’évaluer les différentsenjeux en termes d’occupation du sol et de gestion des eaux pluviales. Cependant, peu demodèles ont été construits pour être appliqués aux bassins périurbains, à l’échelle des gestionnaires(˜ 100 km2) et pour des simulations sur de longues périodes (> 10 ans). La modélisationhydrologique doit donc être adaptée afin de mieux capter les spécificités des milieux périurbainstelles que l’hétérogénéité de l’occupation du sol et la connexion de certaines zones urbaines à unréseau d’assainissement.Ce travail de thèse a consisté à développer un nouvel outil de modélisation adapté à ces problématiques: le modèle distribué horaire J2000P. Ce modèle simule les processus hydrologiquesen milieux ruraux et urbains et prend en compte les réseaux d’assainissement, les connexionsà ces réseaux et les déversements des déversoirs d’orage (DO). Le modèle a été mis en oeuvresur le bassin périurbain de l’Yzeron (˜ 130 km2), situé à l’ouest de Lyon. L’évaluation, effectuéeà l’exutoire de différents sous-bassins de tailles et d’occupations du sol différentes, montre desrésultats très encourageants. Le modèle a tendance à sous-estimer le débit mais la dynamiquedes pics est bien représentée tout comme le déversement des DO. Suite aux résultats de l’évaluation,une analyse de sensibilité « pas à pas » du modèle a été réalisée et différentes hypothèsesde fonctionnement du bassin ont été formulées pour améliorer la compréhension du modèle etdes processus représentés. Le modèle a ensuite été utilisé pour tester l’impact de modificationsde l’occupation des sols et/ou de la gestion des eaux pluviales sur la réponse hydrologique. Lemodèle montre que la gestion de l’occupation du sol a moins d’influence sur l’hydrologie dubassin que la gestion du réseau d’assainissementGrowing urbanization and related anthropogenic processes have a high potential to influencehydrological process dynamics. Typical consequences are an increase of surface imperviousnessand modifications of water flow paths due to artificial channels and barriers (combined and separatedsystem, sewer overflow device, roads, ditches, etc.). Periurban catchments, at the edgeof large cities, are especially affected by fast anthropogenic modifications. They usually consistof a combination of natural areas, rural areas with dispersed settlements and urban areas mostlycovered by built zones and spots of natural surfaces. Spatialized hydrological modeling tools, simulatingthe entire hydrological cycle and able to take into account the important heterogeneityof periurban watersheds can be used to assess the impact of stormwater management practiceson their hydrology.We propose a new modeling tool for these issues : the hourly distributed J2000P model.This model simulates the hydrological processes in rural and urban areas and takes into accountthe sewerage networks, connections to these networks and overflows from sewer overflow devices(SOD). The application site is the Yzeron catchment (˜ 130 km2), located in the West of Lyon.The evaluation, conducted at the outlet of different sub-basins with different sizes and landuse, shows very encouraging results. The model tends to underestimate the discharge but thedynamics of the peaks and the SOD overflows are well simulated. The model is also used to testthe impact of changes in land use and/or stormwater management on the hydrological response.The results show that land use management has less impact on the hydrology of the catchmentthan stormwater management
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Rudnick, Sebastian. "Hydrological modelling of a catchment supported by the discharge of treated wastewater - A comparison of two model concepts." Doctoral thesis, Humboldt-Universität zu Berlin, 2018. http://dx.doi.org/10.18452/19501.
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Die Untersuchung von Klimaszenarien ergab, dass die Grundwasserneubildung in Nordostdeutschland abnehmen könnte. Um Süßgewässer zu erhalten müssen neue Strategien entwickelt werden. Im Gebiet des Lietzengrabens wird Klarwasser eingeleitet, um Feuchtgebiete und Seen zu erhalten. Diese Strategie wurde durch eine Szenarioanalyse erarbeitet, die sich auf das hydrologische iterative Modell ArcEGMO-ASM stützte.
In dieser Arbeit wurde das voll integrierte Modell HydroGeoSphere genutzt, um den Fluss von Wasser an der Oberfläche und im Untergrund zu simulieren. Basierend auf dieser Simulation wurden Fließpfade und Aufenthaltszeiten abgeschätzt.
Die Ergebnisse beider Modelle wurden analysiert und verglichen. Mit beiden Modellen war es möglich, die Abfluss- und Grundwasserdynamiken im Einzugsgebiet zu reproduzieren. Bei der Anwendung von HydroGeoSphere fehlten Möglichkeiten zur Berücksichtigung von z.B. Schneefall und Wehren, welche in ArcEGMO-ASM vorhanden sind.
Die Kalibrierung des Modells lieferte Parameterwerte, die eine Reproduktion der Dynamiken erlaubten. Allerdings könnte HydroGeoSphere nur eingeschränkt nutzbar sein, da die Werte teils unrealistisch waren. HydroGeoSphere ermöglichte aber die Abschätzung von unterirdischen Fließpfaden und Aufenthaltszeiten.
Weiter wurde der Austritt von Grundwasser in einen Bachabschnitt durch Messungen bestimmt und mit Simulationsergebnissen verglichen. Keines der Modelle war geeignet, die räumlichen Muster auf dieser Skala zu reproduzieren. Die simulierten Exfiltrationsraten wichen von den beobachteten ab.
Der Vergleich von ArcEGMO-ASM und HydroGeoSphere zeigte die Vorteile und Grenzen der Modelle auf. Der Einsatz von HydroGeoSphere bei Untersuchungen von Bewirtschaftungsstrategien macht sich noch nicht bezahlt, vergleicht man den Aufwand mit den Vorteilen. Da HydroGeoSphere weiterentwickelt wird und die Rechenkapazitäten zunehmen, könnte das Modell in der nahen Zukunft in der Praxis nutzbar sein.Analysis of climatic scenarios for North-East Germany showed that groundwater recharge could decline. In order to sustain freshwaters, new strategies must be developed. At the Lietzengraben catchment treated wastewater is discharged to sustain wetlands and lakes in the catchment. This management strategy was developed previously by scenario analysis, performed by the hydrological iterative model ArcEGMO-ASM. In this work, the fully integrated model HydroGeoSphere was used to simulate the surface and subsurface water flow in the catchment. Based on the simulation results, flow paths and residence times were estimated. The results of the simulations by both models were investigated and compared. It was possible to reproduce the catchment dynamics regarding discharge and groundwater heads reasonably well with both models. The application of HydroGeoSphere was limited due to the inability of the model to represent features like snowfall and weirs, which are represented in ArcEGMO-ASM. The calibrated parameter values enabled the model to reproduce the catchment dynamics reasonably well. HydroGeoSphere may be limited in its use since the obtained values are partially unrealistic. HydroGeoSphere allowed the approximation of subsurface flow paths and residence times. The exfiltration of groundwater to a stream reach was estimated by measurements and compared to simulation results. Both models were not able to reproduce the spatial patterns on a sub-reach scale and the calculated exfiltration rates did not match the observed rates. The comparison of ArcEGMO-ASM and HydroGeoSphere showed the advantages and limitations of both models. Comparing the overall additional effort to the benefits, however, the application of HydroGeoSphere to investigations regarding management strategies or scenario analyses may not pay off. Since HydroGeoSphere is under steady development and computational resources improve, the use of HydroGeoSphere may be applicable in the near future.
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Bari, Mohammed A. "A distributed conceptual model for stream salinity generation processes : a systematic data-based approach." University of Western Australia. School of Earth and Geographical Sciences, 2006. http://theses.library.uwa.edu.au/adt-WU2006.0058.
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[Truncated abstract] During the last fifty years mathematical models of catchment hydrology have been widely developed and used for hydrologic forecasting, design and water resources management. Most of these models need large numbers of parameters to represent the flow generation process. The model parameters are estimated through calibration techniques and often lead to ‘unrealistic’ values due to structural error in the model formulations. This thesis presents a new strategy for developing catchment hydrology models for representing streamflow and salinity generation processes. The strategy seeks to ‘learn from data’ in order to specify a conceptual framework that is appropriate for the particular space and time scale under consideration. Initially, the conceptual framework is developed by considering large space and time scales. The space and time scales are then progressively reduced and conceptual model complexity systematically increased until ultimately, an adequate simulation of daily streamflow and salinity is achieved. This strategy leads to identification of a few key physically meaningful parameters, most of which can be estimated a priori and with minimal or no calibration. Initially, the annual streamflow data from ten experimental catchments (control and cleared for agriculture) were analysed. The streamflow increased in two phases: (i) immediately after clearing due to reduced evapotranspiration, and (ii) through an increase in stream zone saturated area. The annual evapotranspiration losses from native vegetation and pasture, the ‘excess’ water (resulting from reduced transpiration after land use change), runoff and deep storage were estimated by a simple water balance model. The model parameters are obtained a priori without calibration. The annual model was then elaborated by analysing the monthly rainfall-runoff, groundwater and soil moisture data from four experimental catchments. Ernies (control, fully forested) and Lemon (53% cleared) catchments are located in zone with a mean annual rainfall of 725 mm. Salmon (control, fully forested) and Wights (100% cleared) are located in zone with mean annual rainfall of 1125 mm. Groundwater levels rose and the stream zone saturated area increased significantly after clearing. From analysis of this data it was evident that at a monthly time step the conceptual model framework needed to include a systematic gain/loss to storage component in order to adequately describe the observed lags between peak monthly rainfall and runoff.
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Ma, Qiang. "Modélisation hydrologique déterministe pour les systèmes d'aide à la décision en temps réel : application au bassin versant Var, France." Thesis, Université Côte d'Azur (ComUE), 2018. http://www.theses.fr/2018AZUR4015/document.
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Les ressources en eau sont généralement considérées comme l'une des ressources naturelles les plus importantes du développement social, en particulier pour soutenir les usages domestiques, agricoles et industriels. Au cours de la dernière décennie, en raison de l'augmentation des activités humaines, telles que l'urbanisation et l'industrialisation, les impacts sociaux sur l'environnement naturel deviennent de plus en plus intenses. Par conséquent, de nos jours, les problèmes d'eau par rapport à avant deviennent plus compliqués. Pour faire face au problème complexe depuis les années 1970, les gens ont reconnu que le système d'aide à la décision (DSS) présente des avantages évidents. De plus, avec le développement de l'informatique et des techniques web, les DSS sont souvent utilisés pour appuyer la décision locale. Les décideurs pour gérer les ressources naturelles de la région en particulier les ressources en eau. La modélisation hydrologique en charge de la représentation des caractéristiques du bassin versant joue un rôle important dans le système d'aide à la décision environnementale (EDSS). Parmi les différents types de modèles, le modèle hydrologique distribué déterministe est capable de décrire l'état réel de la zone d'étude de manière plus détaillée et précise. Cependant, le seul obstacle à la limitation des applications de ce type de modèle est pointé vers le grand besoin de données demandé par sa configuration de modélisation. Dans cette étude d'évaluation de la modélisation hydrologique dans le projet AquaVar, un modèle distribué déterministe (MIKE SHE) est construit pour l'ensemble du bassin versant du Var avec moins d'informations de terrain disponibles dans la zone. Grâce à une stratégie de modélisation raisonnable, plusieurs hypothèses sont conçues pour résoudre les problèmes de données manquantes dans les intervalles de temps quotidiens et horaires. La simulation est étalonnée sur une échelle de temps quotidienne et horaire de 2008 à 2011, qui contient un événement de crue extrême en 2011. En raison des impacts des données manquantes sur les entrées et les observations du modèle, l'évaluation de l'étalonnage de la modélisation n'est pas seulement basée sur des coefficients statistiques tels que le coefficient de Nash, mais aussi des facteurs physiques (p. ex. valeurs maximales et débit total). Le modèle calibré est capable de décrire les conditions habituelles du système hydrologique varois, et représente également le phénomène inhabituel dans le bassin versant tel que les inondations et les sécheresses. Le processus de validation mis en œuvre de 2011 à 2014 dans l'intervalle de temps journalier et horaire confirme la bonne performance de la simulation dans le Var. La simulation MIKE SHE dans Var est l'une des parties principales du système de modélisation distribuée déterministe de l'EDSS d'AquaVar. Après l'étalonnage et la validation, le modèle pourrait être utilisé pour prévoir les impacts des événements météorologiques à venir (par exemple, des crues extrêmes) dans cette région et produire les conditions aux limites pour d'autres modèles distribués déterministes dans le système. La conception de l'architecture EDSS, la stratégie de modélisation et le processus d'évaluation de modélisation présentés dans cette recherche pourraient être appliqués comme un processus de travail standard pour résoudre les problèmes similaires dans d'autres régionsWater resource is commonly considered as one of the most important natural resources in social development especially for supporting domestic, agricultural and industrial uses. During the last decade, due to the increase of human activities, such as urbanization and industrialization, the social impacts on the natural environment become more and more intensive. Therefore, recently, water problems compared to before become more complicated. To deal with the complex problem, since 1970s, started from the companies, people recognized that the Decision Support System (DSS) has obvious advantages Moreover, with the development of computer science and web techniques, the DSS are commonly applied for supporting the local decision makers to manage the region natural resources especially the water resources. The hydrological modelling in charge of representing the catchment characteristics plays significant role in the Environment Decision Support System (EDSS). Among different kinds of models, the deterministic distributed hydrological model is able to describe the real condition of the study area in more detail and accurate way. However, the only obstacle to limit the applications of this kind of model is pointed to the large data requirement requested by its modelling set up. In this study of hydrological modelling assessment in AquaVar project, one deterministic distributed model (MIKE SHE) is built for the whole Var catchment with less field information available in the area. Through one reasonable modelling strategy, several hypothesises are conceived to solve the missing data problems within daily and hourly time intervals. The simulation is calibrated in both daily and hourly time scale from 2008 to 2011, which contains one extreme flood event at 2011. Due to the impacts of missing data on both model inputs and observations, the evaluation of modelling calibration is not only based on the statistic coefficients such as Nash coefficient, but also effected by some physical factors (e.g. peak values and total discharge). The calibrated model is able to describe usual condition of Var hydrological system, and also represent the unusual phenomenon in the catchment such as flood and drought event. The validation process implemented from 2011 to 2014 within both daily and hourly time interval further proves the good performance of the simulation in Var. The MIKE SHE simulation in Var is one of the main parts of the deterministic distributed modelling system in the EDSS of AquaVar. After the calibration and validation, the model could be able to use for forecasting the impacts of coming meteorological events (e.g. extreme flood) in this region and producing the boundary conditions for other deterministic distributed models in the system. The design of the EDSS architecture, modelling strategy and modelling evaluation process presented in this research could be applied as one standard working process for solving the similar problems in other region
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Estrada, Camilo Ernesto Restrepo. "Use of social media data in flood monitoring." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-19032019-143847/.
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Floods are one of the most devastating types of worldwide disasters in terms of human, economic, and social losses. If authoritative data is scarce, or unavailable for some periods, other sources of information are required to improve streamflow estimation and early flood warnings. Georeferenced social media messages are increasingly being regarded as an alternative source of information for coping with flood risks. However, existing studies have mostly concentrated on the links between geo-social media activity and flooded areas. This thesis aims to show a novel methodology that shows a way to close the research gap regarding the use of social networks as a proxy for precipitation-runoff and flood forecast estimates. To address this, it is proposed to use a transformation function that creates a proxy variable for rainfall by analysing messages from geo-social media and precipitation measurements from authoritative sources, which are then incorporated into a hydrological model for the flow estimation. Then the proxy and authoritative rainfall data are merged to be used in a data assimilation scheme using the Ensemble Kalman Filter (EnKF). It is found that the combined use of authoritative rainfall values with the social media proxy variable as input to the Probability Distributed Model (PDM), improves flow simulations for flood monitoring. In addition, it is found that when these models are made under a scheme of fusion-assimilation of data, the results improve even more, becoming a tool that can help in the monitoring of \"ungauged\" or \"poorly gauged\" catchments. The main contribution of this thesis is the creation of a completely original source of rain monitoring, which had not been explored in the literature in a quantitative way. It also shows how the joint use of this source and data assimilation methodologies aid to detect flood events.As inundações são um dos tipos mais devastadores de desastres em todo o mundo em termos de perdas humanas, econômicas e sociais. Se os dados oficiais forem escassos ou indisponíveis por alguns períodos, outras fontes de informação são necessárias para melhorar a estimativa de vazões e antecipar avisos de inundação. Esta tese tem como objetivo mostrar uma metodologia que mostra uma maneira de fechar a lacuna de pesquisa em relação ao uso de redes sociais como uma proxy para as estimativas de precipitação e escoamento. Para resolver isso, propõe-se usar uma função de transformação que cria uma variável proxy para a precipitação, analisando mensagens de medições geo-sociais e precipitação de fontes oficiais, que são incorporadas em um modelo hidrológico para a estimativa de fluxo. Em seguida, os dados de proxy e precipitação oficial são fusionados para serem usados em um esquema de assimilação de dados usando o Ensemble Kalman Filter (EnKF). Descobriu-se que o uso combinado de valores oficiais de precipitação com a variável proxy das mídias sociais como entrada para o modelo distribuído de probabilidade (Probability Distributed Model - PDM) melhora as simulações de fluxo para o monitoramento de inundações. A principal contribuição desta tese é a criação de uma fonte completamente original de monitoramento de chuva, que não havia sido explorada na literatura de forma quantitativa.
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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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Dorval, Farah Altagracia. "Mise au point de techniques de traitement de données en continu pour l’identification des composantes de débit à l’exutoire des bassins versants urbains : étude de cas des bassins versants Django Rheinhardt et Ecully." Thesis, Lyon, INSA, 2011. http://www.theses.fr/2011ISAL0058/document.
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L’objectif de cette thèse est de développer, tester et valider des méthodes, techniques et outils permettant de traiter et décomposer les hydrogrammes en temps sec et en temps de pluie, dans le but de comprendre, de représenter et de prédire les dynamiques liées à ces composantes de débits sur des bassins versants urbanisés. Les données en continu de temps sec recueillies sur ces deux bassins versants Chassieu et Ecully ont été traitées à partir de la méthode de traitement des signaux bruités par ondelettes, puis analysées. L’utilisation de ces méthodes et l’analyse des données en continu a permis de mettre en évidence des composantes périodiques intra et inter journalières dans les débits mesurés. Ces composantes ont ensuite été caractérisées puis ont servi de base pour l’élaboration d’une typologie des hydrogrammes de temps sec relatif à chaque site d’étude. Des méthodes, techniques et outils de traitement, d’analyse de séries de données et de calage de modèles pluie-débit ont également été utilisés et deux modèles pluie-débit ont été proposés pour représenter : (i.) la composante liée aux eaux de ruissellement pour les deux sites d’études et (ii.) la composante d’eaux parasites d’infiltration événementielle. La typologie des hydrogrammes de temps sec ainsi que les modèles de production de flux d’eaux en périodes pluvieuses ont été implémentés dans une plate-forme de modélisation hydrologique appelée « Hydrobox ». Les débits simulés ont ensuite été confrontés aux débits mesurés. Les résultats de comparaison montrent l’intérêt de prendre en compte la signature particulière portée par chaque composante dans le but d’améliorer la compréhension et la représentation des dynamiques liées aux processus hydrologiques intervenant sur des bassins versants urbanisésThe objective of this thesis is to develop, test and validate methods, techniques and tools which can process and decompose hydrographs in order to understand, represent and predict the dynamics associated with these flow components in urbanized watersheds. The development of the methodology is based on rainfall and runoff data including qualitatives measures of the flow rate (conductivity, pH and turbidity) continuously acquired as part of the Field Observatory for Urban Hydrology (OTHU) for two watersheds in Lyon: Django Reinhardt (Chassieu) and Ecully. The continuous data collected in dry weather period from these two watersheds were analyzed using wavelets transforms. These methods combined to signal treatments analysis helped to reveal periodic component in the measured flows. These components were then characterized and used as a basis for developing a typology of hydrographs of dry weather period for each study site. Methods, techniques and tools for processing and analyzing of data sets and calibrating of rainfall-runoff models have been used to propose two models which represent respectively: (i) the component related to the runoff contribution for the two study sites and (ii.) the component related to parasitic water infiltration. The typology of hydrographs for dry weather period, the rainfall-runoff model and the infiltration-inflow model were implemented in a platform for hydrological modeling called “Hydrobox”. The simulated and the measured flow values were then compared. The comparison results show the importance of taking into account the particular signature carried by each component in order to improve the understanding and representing the dynamics related to hydrological processes in urbanized watersheds
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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.
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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.
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Snowdon, Andrew. "Improved Numerical Methods for Distributed Hydrological Models." Thesis, 2009. http://hdl.handle.net/10012/4963.
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Distributed hydrological models have been used for decades to calculate and predict the movement of water and energy within watersheds. These models have evolved from relatively simple empirical applications into complex spatially distributed and physically-based programs. However, the evolution of distributed hydrological models has not involved the improvement of the numerical methods used to calculate the redistribution of water and energy in the watershed. Because of this, many models still use numerical methods that are potentially inaccurate.
In order to simulate the transport of water and energy in a hydrological model, typical numerical methods employ an operator splitting approach. Operator splitting (OS) essentially breaks down the set of coupled ordinary differential equations (ODEs) that define a hydrological model into separate ODEs that can be solved individually. The dominant operator splitting method in surface water models is the ordered series approach. Because the ordered series approach treats parallel hydrological processes as if they happen in series, it is prone to errors that can significantly reduce the accuracy of model results. The impact that operator splitting errors have upon hydrologic model results is, to date, unknown.
Using a new distributed hydrological model, Raven, the impact of operator splitting errors is investigated. Understanding these errors will lead to better numerical methods for reducing errors in models and to shed light on the shortcomings of hydrological models with respect to numerical method choice. Alternative numerical methods - the explicit Euler and the implicit iterative Heun methods - are implemented and assessed in their ability to minimize errors and produce more accurate distributed hydrological models.
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Liu, Guoxiang. "Improved Interflow and Infiltration Algorithms for Distributed Hydrological Models." Thesis, 2010. http://hdl.handle.net/10012/5519.
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The shallow subsurface controls the partitioning of available energy between sensible and latent heat of the land surface, and the partitioning of available water among evaporation, infiltration, and runoff. It is a key component of both the hydrometeorological system and the terrestrial water cycle. A critical part of any hydrological or hydrometeorological forecast model is therefore the algorithms used to represent the shallow soil processes, which include infiltration, evaporation, runoff, and interflow. For climate models, coupled algorithms called “Land Surface Schemes” (LSSs) are developed to represent the lower boundary conditions that deal with the land-to-atmosphere energy and moisture fluxes. Similar algorithms are implemented in regional watershed models and day-to-day operational water resources forecasting models. It is the primary objective of this thesis to provide improved methods for simulating coupled land surface processes, which can be used as components of LSSs or within existing operational hydrology models. These new methods address a number of specific issues inadequately handled by current models, including the presence of shallow boundary conditions, heterogeneity in infiltration, and infiltration and interflow coupling processes.
The main objective of the proposed research is to provide consistent physically-based approach for simulating near surface soil moisture processes, so as to complete the parameterization of the interflow/infiltration algorithm in a Hydrology-Land-Surface scheme MESH. The work mainly focuses on the investigation and development of more physically-based infiltration and interflow algorithms. The hope is to determine appropriate relationships between internal state variables (specifically bulk soil moisture) and system boundary fluxes, while simultaneously reducing the number of nonphysical or unknown model parameters. Fewer parameters lead to reduced calibration requirements for distributed hydrological models and consequently accelerate the transfer of such models to engineering practice.
Multiple approaches were taken to provide improved relationships between infiltration and lateral drainage, fluxes and storage. These algorithms were tested by a specialized Richards' equation for sloping soils and Monte Carlo simulations. These tests demonstrated reasonable accuracy and improved representation for the hydrological processes.