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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Extreme flood frequency analysis and flood risk curve development considering spatiotemporal rainfall variability / 降雨の時空間分布を考慮した洪水極値頻度解析と水害リスクカーブ作成手法の開発

Tanaka, Tomohiro 23 September 2016 (has links)
付記する学位プログラム名: グローバル生存学大学院連携プログラム / 京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19975号 / 工博第4219号 / 新制||工||1653(附属図書館) / 33071 / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 立川 康人, 教授 寶 馨, 教授 堀 智晴 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
12

A Mean Field Approach to Watershed Hydrology

Bartlett Jr., Mark Stephan January 2016 (has links)
<p>Society-induced changes to the environment are altering the effectiveness of existing management strategies for sustaining natural and agricultural ecosystem productivity. At the watershed scale, natural and agro-ecosystems represent complex spatiotemporal stochastic processes. In time, they respond to random rainfall events, evapotranspiration and other losses that are spatially variable because of heterogeneities in soil properties, root distributions, topography, and other factors. To quantify the environmental impact of anthropogenic activities, it is essential that we characterize the evolution of space and time patterns of ecosystem fluxes (e.g., energy, water, and nutrients). Such a characterization then provides a basis for assessing and managing future anthropogenic risks to the sustainability of ecosystem productivity.</p><p>To characterize the space and time evolution of watershed scale processes, this dissertation introduces a mean field approach to watershed hydrology. Mean field theory (also known as self-consistent field theory) is commonly used in statistical physics when modeling the space-time behavior of complex systems. The mean field theory approximates a complex multi-component system by considering a lumped (or average) effect of all individual components acting on a single component. Thus, the many body problem is reduced to a one body problem. For watershed hydrology, a mean field theory reduces the numerous point component effects to more tractable watershed averages resulting in a consistent method for linking the average watershed fluxes (evapotranspiration, runoff, etc.) to the local fluxes at each point.</p><p>The starting point for this work is a general point description of the soil moisture, rainfall, and runoff system. For this system, we find the joint PDF that describes the temporal variability of the soil water, rainfall, and runoff processes. Since this approach does not account for the spatial variability of runoff, we introduce a probabilistic storage (ProStor) framework for constructing a lumped (unit area) rainfall-runoff response from the spatial distribution of watershed storage. This framework provides a basis for unifying and extending common event-based hydrology models (e.g. Soil Conservation Service curve number (SCS-CN) method) with more modern semi-distributed models (e.g. Variable Infiltration Capacity (VIC) model, the Probability Distributed (PDM) model, and TOPMODEL). In each case, we obtain simple equations for the fractions of the different source areas of runoff, the spatial variability of runoff and soil moisture, and the average runoff value (i.e., the so-called runoff curve). Finally, we link the temporal and spatial descriptions with a mean field approach for watershed hydrology. By applying this mean field approach, we upscale the point description with the spatial distribution of soil moisture and parameterize the numerous local interactions related to lateral fluxes of soil water in terms of its average. With this approach, we then derive PDFs that represent the space and time distribution of soil water and associated watershed fluxes such as evapotranspiration and runoff.</p> / Dissertation
13

Vliv prostorové schematizace povodí na přesnost modelu akumulace a tání sněhu / Influence of catchment spatial subdivision on the accuracy of the snow accumulation and snowmelt model

Hájková, Barbora January 2013 (has links)
Influence of catchment spatial subdivision on the accuracy of the snow accumulation and snowmelt model Abstract This thesis is focused on influence of catchment spatial subdivision on the accuracy of rainfall-runoff model simulations. A hydrological model HEC-HMS developed by U.S. Army Corps of Engineers was applied in the thesis. Study area includes two experimental catchments; Bystřice River basin and Zlatý Brook basin. Both catchments are located in the Krušné Mountains. The research in catchments has been carried out by the Department of Physical Geography and Geoecology since 2008. The influence of four different horizontal and vertical catchments delineation on runoff simulations was analyzed. The simulations were performed in two two-year periods 11/2008-10/2010 and 11/2010-10/2012. The attention was mainly aimed to snowmelt component of the model, for which temperature index method was chosen. The results of simulations were compared with water stages data measured in catchments outlets and with data from winter field measurements (snow depth and snow water equivalent). The results from both catchments showed that higher accuracy of simulation of the snow water equivalent was reached by dividing the catchments into more elevation zones. However, each of the catchments behaved in different way. The...
14

Aplikace degree-day modelu akumulace a tání sněhu v povodí Ptačího potoka / Application of degree-day accumulation and snowmelt model in the Ptačí Brook basin

Beitlerová, Hana January 2012 (has links)
Snow accumulation and snowmelt research is one of the most important hydrological issues in mountain areas World-wide. Spring snowmelt, usually in the combination with intensive rainfall or high air temperature, is one of the most common causes of flooding in the Czech Republic. Mathematical modeling of hydrological processes belongs to effective instruments of flood protection and finds its use in a variety of areas. For example, water management, hydrological forecasts for agriculture, information for dam regulation or for recreational areas and water sports are all affected. This thesis focuses on snow accumulation and snowmelt modeling with use of the empirical Degree-day method. This method is based on the relationship between snowmelt rate and air temperature. The American HAC-HMS programme is used for the simulation of hydrological processes. The main goal of this thesis is to calibrate the model and to simulate snow accumulation, snowmelt and run-off from the watershed. The experimental basin 'Ptačí potok' is situated in the central part of the Šumava Mountains, in altitude of about 1,200 m. Two winter seasons, 2011 and 2012, were simulated. Simulations showed high reliability and correct calibration of the Temperature index snowmelt model. Simulations of the snow water equivalent evolution...
15

Application du modèle distribué événementiel SCS-LR pour la prévision des crues méditerranéennes : performances du modèle et variabilité spatiale des paramètres / A distributed parsimonious event-based model for flood forecasting in Mediterranean catchments : efficiency of the model and spatial variability of the parameters

Nguyen, Quoc Son 04 July 2019 (has links)
Les modèles pluie-débit sont des outils essentiels pour de nombreuses applications hydrologiques, notamment la prévision des crues. L’objet de cette thèse est d’examiner les performances d’un modèle événementiel distribué, dont l’intérêt est de résumer la représentation des processus à la phase de crue, et la condition initiale à un indice de saturation du bassin facilement observable ou accessible. Ce dernier dispense de modéliser la phase inter-crue, et simplifie la paramétrisation et le calage du modèle. Le modèle étudié combine une fonction de production type SCS et une fonction de transfert type lag and route, appliquées à une discrétisation du bassin en mailles carrées régulières.Le modèle est d’abord testé sur le bassin versant du Real Collobrier. Ce bassin méditerranéen est suivi depuis plus de 50 ans par l’IRSTEA, et dispose d’une exceptionnelle densité de mesures de pluies et de débits. Cet environnement favorable permet de limiter les incertitudes sur l’estimation des pluies et d’évaluer les performances intrinsèques du modèle. Dans ces conditions, les crues sont bien reconstituées à l’aide d’un jeu de paramètres unique pour l’ensemble des épisodes testés, à l’exception de la condition initiale du modèle. Celle-ci apparaît fortement corrélée avec l’humidité du sol en début d’épisode, et peut être prédéterminée de façon satisfaisante par le débit de base ou l’indice w2 fourni par le modèle SIM de Météo-France. Les performances du modèle sont ensuite étudiées en dégradant la densité des pluviomètres, et rendent compte du niveau de performances du modèle dans les cas que l’on rencontre le plus souvent. .La variabilité spatiale des paramètres du modèle est étudiée à l’échelle de différents sous-bassins du Real Collobrier. La comparaison a permis de mettre en évidence et de corriger un effet d’échelle concernant l’un des paramètres de la fonction de transfert. Les relations entre la condition initiale du modèle et les indicateurs d’humidités des sols en début d’épisode restent bonnes à l’échelle des sous-bassins, mais peuvent être significativement différentes selon les sous-bassins. Une seule relation ne permet pas de normaliser l’initialisation du modèle sur l’ensemble des sous-bassins, à une échelle spatiale de quelques km2 ou dizaines de km2. Dans le cas de l’indice d’humidité du sol w2, une explication possible est que cet indice ne prend pas en compte suffisamment finement les propriétés des sols. Enfin, la variabilité spatiale des paramètres du modèle est étudiée à l’échelle d’un échantillon d’une quinzaine de bassins méditerranéens de quelques centaines de km2, associés à des paysages et des fonctionnements hydrologiques divers. La comparaison montre qu’à cette échelle, le lien entre les indicateurs de saturation du bassin et la condition initiale peut rester stable par type de bassin, mais varie significativement d’un type de bassin à l’autre. Des pistes sont proposées pour expliquer cette variation.En conclusion, ce modèle événementiel distribué représente un excellent compromis entre performances et facilité de mise en œuvre. Les performances sont satisfaisantes pour un bassin donné ou pour un type de bassin donné. L’analyse et l’interprétation de la variabilité spatiale des paramètres du modèle apparaît cependant complexe, et doit faire l’objet du test d’autres indicateurs de saturation des bassins, par exemple mesures in situ ou mesures satellitaires de l’humidité des sols. / Rainfall-runoff models are essential tools for many hydrological applications, including flood forecasting. The purpose of this thesis was to examine the performances of a distributed event model for reproducing the Mediterranean floods. This model reduces the parametrization of the processes to the flood period, and estimates the saturation of the catchment at the beginning of the event with an external predictor, which is easily observable or available. Such predictor avoids modelling the inter-flood phase and simplifies the parametrization and the calibration of the model. The selected model combines a distributed SCS production function and a Lag and Route transfer function, applied to a discretization of the basin in a grid of regular square meshes.The model was first tested on the Real Collobrier watershed. This Mediterranean basin has been monitored by IRSTEA for more than 50 years and has an exceptional density of rainfall and flow measurements. This favourable environment made it possible to reduce the uncertainties on the rainfall input and to evaluate the actual performances of the model. In such conditions, the floods were correctly simulated by using constant parameters for all the events, but the initial condition of the event-based model. This latter was highly correlated to predictors such as the base flow or the soil water content w2 simulated by the SIM model of Meteo-France. The model was then applied by reducing the density of the rain gauges, showing loss of accuracy of the model and biases in the model parameters for lower densities, which are representative of most of the catchments.The spatial variability of the model parameters was then studied in different Real Collobrier sub-basins. The comparison made it possible to highlight and correct the scale effect concerning one of the parameters of the transfer function. The catchment saturation predictors and the initial condition of the model were still highly correlated, but the relationships differed from some sub-catchments. Finally, the spatial variability of the model parameters was studied for other larger Mediterranean catchments, of which area ranged from some tenth to hundreds of square kilometres. Once more, the model could be efficiently initialized by the base flow and the water content w2, but significant differences were found from a catchment to another. Such differences could be explained by uncertainties affecting as well the rainfall estimation as the selected predictors. However, the relationships between the initial condition of the model and the water content w2 were close together for a given type of catchment.In conclusion, this distributed event model represents an excellent compromise between performance and ease of implementation. The performances are satisfactory for a given catchment or a given type of catchment. The transposition of the model to ungauged catchment is less satisfactory, and other catchment saturation indicators need to be tested, e.g. in situ measurements or satellite measurements of soil moisture.
16

Amélioration d'une modélisation hydrologique régionalisée pour estimer les statistiques d'étiage / Improvement of a regionalized rainfall-runoff model to estimate low-flow indices

Garcia, Florine 15 December 2016 (has links)
L'estimation d'indices d'étiage est d'une grande importance pour une meilleure connaissance de la ressource en eau disponible et en déduire des règles de gestion de cette ressource et des risques associés. Idéalement, ces indices sont calculés en sites jaugés à partir de longues chroniques de débits mesurés. En sites non jaugés, ces indices doivent être estimés. Cette thèse s'inscrit dans le projet d'amélioration de l'outil informatique " LoiEau " utilisé par les DREAL et les Agences de l'eau. Le principal objectif est de développer un modèle hydrologique simple et flexible pour estimer tous les indices d'étiage souhaités à des intervalles de temps journaliers ou supérieurs en sites non jaugés. La simplicité du modèle repose sur l'hypothèse forte que deux paramètres plus facilement régionalisables suffisent à estimer les indices avec une précision voulue. Cette précision dépend de la fonction objectif qu'il a fallu adapter aux faibles débits pour caler convenablement les paramètres du modèle sur des sites jaugés. Le modèle se veut flexible dans le sens où il est applicable à une large variété de bassins versants. Il a été comparé au modèle journalier à quatre paramètres GR4J et au modèle mensuel à deux paramètres LoiEau en s'intéressant aussi à la façon de régionaliser les paramètres. Des comparaisons ont également été réalisées avec une méthode d'estimation dite stochastique d'un indice d'étiage classique. Ces travaux montrent le potentiel du modèle à deux paramètres et l'avantage du pas de temps journalier, la variabilité temporelle des précipitations n'étant pas sans conséquence sur l'estimation de débits moyens en raison de la non-linéarité des modèles pluies-débits. / Estimating low-flow indices is of paramount importance to understand low flows and to manage water resources and risk assessments. These indices are derived from time-series of river discharges that are measured at gauged sites over long periods. At ungauged sites, the indices must be estimated. This research work is part of a project to improve “LoiEau”, a software package that is used by French regional environmental or water agencies. The main objective is to develop a simple and flexible rainfall-runoff model to simulate low-flow indices of ungauged sites at daily or longer time intervals. The model simplicity relies on the strong assumption that two free parameters are sufficient to provide accurate enough estimates of low-flow indices, yet making easier the regionalisation of models. The model accuracy depends on the objective function that is used to calibrate model parameters on gauged sites and had to be adapted to low-flow simulations. The model is flexible in the sense that it is designed to fit to a wide variety of catchments and hydro-meteorological behaviours. This model was compared with GR4J, a daily rainfall-runoff model which involves four parameters, and LoiEau, a monthly model. Comparisons were also carried out with a stochastic estimation method applied to a specific low-flow index. This research work shows the potential of the two-parameter model, but also the advantage of a daily time step to account for the temporal variability of precipitations, which is not without consequence on the assessment of average discharges due to the nonlinearity of rainfall-runoff models.
17

Kvantifikace přirozené vodní retenční schopnosti krajiny ve vybraných povodích / Quantification of natural water retention capacity in selected watersheds

Pavlík, František January 2014 (has links)
The aim of this work is to quantify the natural water retention capacity of the landscape in selected catchments and determine the significance of selected climatic and geographic basin factors on components of retention capacity. 18 rainfall-runoff events were selected in 11 catchments for quantification of the natural water retention capacity of landscape. Land cover, geomorphological, pedological and hydrological conditions were analyzed for this basin using GIS tools. Historical rainfall-runoff events for which were restored historical land cover were also evaluated in this work. Two different methods were used for the quantification of retention capacity, one of them was used in two variants. A rainfall-runoff models and simulated scenarios of land cover (positive and negative) were constructed in two selected catchments in HEC-HMS. The work also use previously performed simulation scenarios of land cover formulated by other authors. Total final set of 33 rainfall-runoff events were subjected to statistical correlation and regression analysis. The goal of these analyses was to determine the significance of individual parameters assessed in relation to the components of natural water retention of catchment.
18

Atualização de dados de entrada aplicada à previsão de vazões de curto prazo

Ticona Gutierrez, Juan Carlos January 2015 (has links)
Neste estudo, foi realizada uma revisão dos problemas observados na modelagem chuva-vazão, que influenciam a incerteza das condições iniciais dos processos de previsão de vazão. Foi realizada, também, uma revisão do estado da arte de alguns dos modelos de previsão de vazão de curto prazo utilizados no Brasil e, por último, uma revisão das metodologias de atualização de dados empregadas em trabalhos passados. Mas o principal enfoque deste estudo foi à elaboração de uma metodologia de atualização de dados de entrada, baseada na correção do desvio entre a vazão de saída de um modelo hidrológico e a vazão observada, por meio da perturbação dos dados de entrada de precipitação. O estudo de caso está composto por três bacias: Bacia do rio Ijuí, Bacia do rio Tesouras e a Bacia do rio Canoas. Estas bacias foram escolhidas, pois apresentam características distintas, tanto físicas quanto climáticas e, além disso, pela existência de estudos prévios com o modelo hidrológico utilizado neste trabalho. O processo de avaliação do método foi realizado em três etapas: 1) utilizando séries sintéticas; 2) utilizando séries reais; 3) previsão de vazões com atualização de dados. As duas primeiras etapas utilizaram o modelo em modo atualização (“off-line”) e, a última, o modelo em modo de previsão (“on-line”). Para a aplicação do método é necessário estabelecer condições de parada, sendo então, propostos dois conjuntos de critérios de parada. Com isto, foi estabelecido um conjunto adequado de critérios para que estes fiquem fixos para possibilitar futuras aplicações em outros modelos ou em outros estudos de casos. A técnica de previsão de vazão de curto prazo utilizada foi com base na chuva prevista, sendo adotada a previsão de chuva conhecida ou perfeita. Foram geradas previsões diárias de até 7 dias, durante 20 dias contínuos, escolhendo-se dois eventos de diferentes características em cada uma das bacias do estudo de caso. Em modo previsão os resultados se mostraram promissores, o objetivo desejado inicialmente foi atingido pelos dois conjuntos de critérios de parada propostos. Conseguiu-se ter um ganho significativo até o quarto dia de previsão, como, também, melhoras nos períodos de subidas do hidrograma, porém nos períodos de estiagens o ganho foi quase nulo. Além disso, este trabalho mostrou a viabilidade da utilização do modelo IPH II para a geração de previsões de vazões baseadas em previsão de chuva. / In this study a review of the problems observed in rainfall-runoff modeling has been made, which influence the uncertainty of initial conditions of flow forecasting processes, as well as a review of the state of the art of some of the short-term flow forecasting models used in Brazil and the data update methodologies used in many past jobs. However the focus of this study has been the development of a data entry update methodology based on the correction of the deviation between the output flow of a hydrological model and the observed flow, by means of the disruption of rainfall input data. The case study is composed of the three river basins: River Ijuí, River Tesouras and Canoas. These basins have been chosen due to their different characteristics, both physical and climate, besides having been used in previous studies of the hydrological model used. The evaluation process of the method is done in three steps: 1) using synthetic series; 2) using real series; 3) stream flow forecasting with data update, the first two with the model in update mode ("off-line") and the last in predict mode ("on-line"). For the application of this method is necessary to establish stopping conditions for application, and for this have been proposed two sets of stop criteria. With this, intended to establish an appropriate set of criteria so that they become fixed to permit future applications in other models. The short-term flow forecasting technique used has been based on the forecast rain, adopted the rain forecast known or perfect. Predictions have been generated daily up to 7 days, for 20 consecutive days, choosing two events of different features in each case study basins. In predict mode the results have been promissory, the desired goal initially achieved by the two sets of proposed stopping criteria. It was possible to have a significant gain until the fourth day forecast also improvements in periods of hydrograph increases but not during periods of drought the gain was almost nil. This work has also showed the ability to generate predictions of rain forecast based flow as the IPH II model in real time.
19

Atualização de dados de entrada aplicada à previsão de vazões de curto prazo

Ticona Gutierrez, Juan Carlos January 2015 (has links)
Neste estudo, foi realizada uma revisão dos problemas observados na modelagem chuva-vazão, que influenciam a incerteza das condições iniciais dos processos de previsão de vazão. Foi realizada, também, uma revisão do estado da arte de alguns dos modelos de previsão de vazão de curto prazo utilizados no Brasil e, por último, uma revisão das metodologias de atualização de dados empregadas em trabalhos passados. Mas o principal enfoque deste estudo foi à elaboração de uma metodologia de atualização de dados de entrada, baseada na correção do desvio entre a vazão de saída de um modelo hidrológico e a vazão observada, por meio da perturbação dos dados de entrada de precipitação. O estudo de caso está composto por três bacias: Bacia do rio Ijuí, Bacia do rio Tesouras e a Bacia do rio Canoas. Estas bacias foram escolhidas, pois apresentam características distintas, tanto físicas quanto climáticas e, além disso, pela existência de estudos prévios com o modelo hidrológico utilizado neste trabalho. O processo de avaliação do método foi realizado em três etapas: 1) utilizando séries sintéticas; 2) utilizando séries reais; 3) previsão de vazões com atualização de dados. As duas primeiras etapas utilizaram o modelo em modo atualização (“off-line”) e, a última, o modelo em modo de previsão (“on-line”). Para a aplicação do método é necessário estabelecer condições de parada, sendo então, propostos dois conjuntos de critérios de parada. Com isto, foi estabelecido um conjunto adequado de critérios para que estes fiquem fixos para possibilitar futuras aplicações em outros modelos ou em outros estudos de casos. A técnica de previsão de vazão de curto prazo utilizada foi com base na chuva prevista, sendo adotada a previsão de chuva conhecida ou perfeita. Foram geradas previsões diárias de até 7 dias, durante 20 dias contínuos, escolhendo-se dois eventos de diferentes características em cada uma das bacias do estudo de caso. Em modo previsão os resultados se mostraram promissores, o objetivo desejado inicialmente foi atingido pelos dois conjuntos de critérios de parada propostos. Conseguiu-se ter um ganho significativo até o quarto dia de previsão, como, também, melhoras nos períodos de subidas do hidrograma, porém nos períodos de estiagens o ganho foi quase nulo. Além disso, este trabalho mostrou a viabilidade da utilização do modelo IPH II para a geração de previsões de vazões baseadas em previsão de chuva. / In this study a review of the problems observed in rainfall-runoff modeling has been made, which influence the uncertainty of initial conditions of flow forecasting processes, as well as a review of the state of the art of some of the short-term flow forecasting models used in Brazil and the data update methodologies used in many past jobs. However the focus of this study has been the development of a data entry update methodology based on the correction of the deviation between the output flow of a hydrological model and the observed flow, by means of the disruption of rainfall input data. The case study is composed of the three river basins: River Ijuí, River Tesouras and Canoas. These basins have been chosen due to their different characteristics, both physical and climate, besides having been used in previous studies of the hydrological model used. The evaluation process of the method is done in three steps: 1) using synthetic series; 2) using real series; 3) stream flow forecasting with data update, the first two with the model in update mode ("off-line") and the last in predict mode ("on-line"). For the application of this method is necessary to establish stopping conditions for application, and for this have been proposed two sets of stop criteria. With this, intended to establish an appropriate set of criteria so that they become fixed to permit future applications in other models. The short-term flow forecasting technique used has been based on the forecast rain, adopted the rain forecast known or perfect. Predictions have been generated daily up to 7 days, for 20 consecutive days, choosing two events of different features in each case study basins. In predict mode the results have been promissory, the desired goal initially achieved by the two sets of proposed stopping criteria. It was possible to have a significant gain until the fourth day forecast also improvements in periods of hydrograph increases but not during periods of drought the gain was almost nil. This work has also showed the ability to generate predictions of rain forecast based flow as the IPH II model in real time.
20

Atualização de dados de entrada aplicada à previsão de vazões de curto prazo

Ticona Gutierrez, Juan Carlos January 2015 (has links)
Neste estudo, foi realizada uma revisão dos problemas observados na modelagem chuva-vazão, que influenciam a incerteza das condições iniciais dos processos de previsão de vazão. Foi realizada, também, uma revisão do estado da arte de alguns dos modelos de previsão de vazão de curto prazo utilizados no Brasil e, por último, uma revisão das metodologias de atualização de dados empregadas em trabalhos passados. Mas o principal enfoque deste estudo foi à elaboração de uma metodologia de atualização de dados de entrada, baseada na correção do desvio entre a vazão de saída de um modelo hidrológico e a vazão observada, por meio da perturbação dos dados de entrada de precipitação. O estudo de caso está composto por três bacias: Bacia do rio Ijuí, Bacia do rio Tesouras e a Bacia do rio Canoas. Estas bacias foram escolhidas, pois apresentam características distintas, tanto físicas quanto climáticas e, além disso, pela existência de estudos prévios com o modelo hidrológico utilizado neste trabalho. O processo de avaliação do método foi realizado em três etapas: 1) utilizando séries sintéticas; 2) utilizando séries reais; 3) previsão de vazões com atualização de dados. As duas primeiras etapas utilizaram o modelo em modo atualização (“off-line”) e, a última, o modelo em modo de previsão (“on-line”). Para a aplicação do método é necessário estabelecer condições de parada, sendo então, propostos dois conjuntos de critérios de parada. Com isto, foi estabelecido um conjunto adequado de critérios para que estes fiquem fixos para possibilitar futuras aplicações em outros modelos ou em outros estudos de casos. A técnica de previsão de vazão de curto prazo utilizada foi com base na chuva prevista, sendo adotada a previsão de chuva conhecida ou perfeita. Foram geradas previsões diárias de até 7 dias, durante 20 dias contínuos, escolhendo-se dois eventos de diferentes características em cada uma das bacias do estudo de caso. Em modo previsão os resultados se mostraram promissores, o objetivo desejado inicialmente foi atingido pelos dois conjuntos de critérios de parada propostos. Conseguiu-se ter um ganho significativo até o quarto dia de previsão, como, também, melhoras nos períodos de subidas do hidrograma, porém nos períodos de estiagens o ganho foi quase nulo. Além disso, este trabalho mostrou a viabilidade da utilização do modelo IPH II para a geração de previsões de vazões baseadas em previsão de chuva. / In this study a review of the problems observed in rainfall-runoff modeling has been made, which influence the uncertainty of initial conditions of flow forecasting processes, as well as a review of the state of the art of some of the short-term flow forecasting models used in Brazil and the data update methodologies used in many past jobs. However the focus of this study has been the development of a data entry update methodology based on the correction of the deviation between the output flow of a hydrological model and the observed flow, by means of the disruption of rainfall input data. The case study is composed of the three river basins: River Ijuí, River Tesouras and Canoas. These basins have been chosen due to their different characteristics, both physical and climate, besides having been used in previous studies of the hydrological model used. The evaluation process of the method is done in three steps: 1) using synthetic series; 2) using real series; 3) stream flow forecasting with data update, the first two with the model in update mode ("off-line") and the last in predict mode ("on-line"). For the application of this method is necessary to establish stopping conditions for application, and for this have been proposed two sets of stop criteria. With this, intended to establish an appropriate set of criteria so that they become fixed to permit future applications in other models. The short-term flow forecasting technique used has been based on the forecast rain, adopted the rain forecast known or perfect. Predictions have been generated daily up to 7 days, for 20 consecutive days, choosing two events of different features in each case study basins. In predict mode the results have been promissory, the desired goal initially achieved by the two sets of proposed stopping criteria. It was possible to have a significant gain until the fourth day forecast also improvements in periods of hydrograph increases but not during periods of drought the gain was almost nil. This work has also showed the ability to generate predictions of rain forecast based flow as the IPH II model in real time.

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