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Thesis (M. Sc. (Institute for Water Research))--Rhodes University, 2005.

Αντικείμενο της παρούσας εργασίας αποτελεί η εφαρμογή του μοντέλου βροχής-απορροής MIKE-SHE στο ορεινό τμήμα της λεκάνης του Γλαύκου. Σκοπός της μελέτης ήταν η διαμόρφωση της εσωτερικής δομής του MIKE-SHE έτσι ώστε να προσομοιώνει την διαδικασία της απορροής στην λεκάνη του Γλαύκου, η βαθμονόμηση των παραμέτρων του και η σύγκριση των αποτελεσμάτων των μοντέλων βροχής-απορροής MIKE-SHE και ENNS (Nachtnebel et al., 1993). Η ρύθμιση του μοντέλου ENNS πραγματοποιήθηκε στα πλαίσια της εργασίας των Kaleris and Langousis (2012). Ειδικότερα, στο πρώτο κεφάλαιο της εργασίας καθορίζεται η περιοχή μελέτης, τα χαρακτηριστικά της και τα δεδομένα εισαγωγής στο υδρολογικό μοντέλο MIKE SHE. Τα μορφολογικά χαρακτηριστικά αποτελούν η γεωμετρία, η γεωλογία και οι χρήσεις γης της λεκάνης απορροής. Επιπλέον παρουσιάζονται τα διαθέσιμα δεδομένα(βροχόπτωση, θερμοκρασία, μετρημένη απορροή) και η αξιολόγησή τους Στο δεύτερο κεφάλαιο περιγράφεται η αδρομερής μορφή του μοντέλου MIKE-SHE, η οποία χρησιμοποιήθηκε για την προσομοίωση. Για τις επιμέρους διαδικασίες επιλέχτηκαν οι εξής τρόποι υπολογισμού: η επιφανειακή ροή υπολογίζεται με την εξίσωση του Manning, η ροή στην ακόρεστη ζώνη με την μέθοδο του υδατικού ισοζυγίου (απλοποιημένη ροή μέσω μακροπόρων και μοντέλο κατείσδυσης Green and Ampt) και η υπεδάφια απορροή με τη μέθοδο του γραμμικού ταμιευτήρα. Στο τρίτο κεφάλαιο περιγράφεται η διαδικασία βαθμονόμησης των παραμέτρων του μοντέλου MIKE-SHE και παρουσιάζονται οι αναλύσεις ευαισθησίας των σημαντικότερων παραμέτρων του μοντέλου. Η ανάλυση ευαισθησίας για τον προσδιορισμό των τιμών των παραμέτρων του μοντέλου MIKE-SHE πραγματοποιήθηκε για την περίοδο 1984-1989, καθώς ο λόγος ΕΤ/Ρ δεν παρουσιάζει μεγάλες διακυμάνσεις για τις χρονιές αυτές. Οι βέλτιστες τιμές των παραμέτρων για την ρύθμιση του μοντέλου MIKE-SHE, οι οποίες προέκυψαν για την ανωτέρω χρονική περίοδο, εφαρμόστηκαν για την προσομοίωση της απορροής και τις υπόλοιπες χρονιές. Στο τέταρτο κεφάλαιο παρουσιάζονται τα αποτελέσματα του μοντέλου MIKE-SHE σε σύγκριση με εκείνα του μοντέλου βροχής-απορροής ENNS. Αρχικά, συγκρίνεται η συνολική απορροή των δυο μοντέλων μεταξύ τους και με την μετρημένη και εν συνεχεία, συγκρίνονται οι επιμέρους υδρολογικές συνιστώσες του υδρολογικού ισοζυγίου των δυο μοντέλων. Στο τελευταίο κεφάλαιο, παρουσιάζονται συνοπτικά τα συμπεράσματα, τα οποία εξήχθησαν από την σύγκριση των δυο μοντέλων αλλά και από την γενική συμπεριφορά του μοντέλου MIKE-SHE. / The subject of my thesis is the application of the rainfall-runoff model MIKE-SHE in the mountainous part of Glafkos’s basin. The aim of this study is to calibrate the model and to compare the simulations of MIKE-SHE with corresponding simulations of ENNS (Nachtnebel et al., 1993). The simulations with ENNS have been presented by Kaleris and Langousis (2012). Specifically, in the first chapter the study area and its characteristics (morphology, geometry, geology), the available data for the runoff simulations (rainfall, temperature, measured runoff) and their evaluation are presented. In the second chapter is described the structure of the model MIKE-SHE. For the simulation of the individual processes the following concepts are used in MIKE-SHE: the surface flow is calculated using the equation of Manning and for the flow in the unsaturated zone the two-layer water balance method (simplified flow through macropores and infiltration model Green and Ampt) has been used. Finally, for the subsurface runoff the linear reservoir’s equations has been used. In the third chapter the parameters varied in the calibration of MIKE-SHE and the sensitivity of the runoff with respect to these parameters have been presented. By means of the sensitivity analysis the most important parameters, which have been varied for the model calibration have been selected. The fourth chapter presents the results of the MIKE-SHE calibration and their comparison with the results of the rainfall-runoff model ENNS. Particularly, this chapter contains the comparison of the simulated hydrographs of the total runoff with the corresponding measured hydrographs and the hydrographs resulting from ENNS, as well as the comparison of the other water budget components resulting from the two models. The last chapter summarizes the conclusions which are drawn from the comparison of the two models and the evaluation of the behavior of the model MIKE-SHE.

Made available in DSpace on 2015-05-14T12:09:08Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 7934601 bytes, checksum: 83089393956abb6b7fa32c5295791684 (MD5) Previous issue date: 2012-03-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / A major difficulty for studies of small hydrological watersheds is the lack of good quality time series of hydrologic data, mainly because the flow rates in small watersheds are not monitored. Another important issue is that available rainfall runoff models are almost always developed focusing on watersheds of medium and large scale. Regionalization studies have become an important tool to attempt to overcome these limitations. Suitable in most of the hydrological studies is the regionalization of rainfall runoff-model parameters by using specific characteristics of a watershed. A tool was developed in a Geographic Information System which automatically gets the physical characteristics of watersheds from a digital elevation model by selecting the outlet and then generating the rainfall runoff model parameters with neural networks. This study uses data from small dams in the semi-arid region of northeastern Brazil. The developed methodology is applied using target watersheds for the parameter estimation. The results show that the developed tool can be very useful for rainfall runoff estimation in small watersheds. / Uma das maiores dificuldades para os estudos de pequenas bacias hidrográficas é a falta de séries históricas de dados hidrológicos, principalmente porque a fluviometria em pequenas bacias hidrográficas não é monitorada. Outra questão importante é que, os modelos chuva-vazão disponíveis quase sempre são desenvolvidos com foco em bacias de médio e grande porte. Estudos de regionalização se tornaram uma ferramenta importante para tentar superar essas limitações. A regionalização de parâmetros de modelos chuva-vazão, usando características específicas das bacias hidrográficas, é adequada para a maioria dos estudos hidrológicos. Uma ferramenta foi desenvolvida em um Sistema de Informação Geográfica, que determina automaticamente as características físicas das bacias hidrográficas a partir de um modelo digital de elevação, e, em seguida, gera os parâmetros do modelo chuva-vazão com redes neurais artificiais. Este trabalho usa dados de pequenas barragens na região semiárida do Nordeste do Brasil. A metodologia desenvolvida é aplicada e avaliada utilizando também o método da bacia meta para a estimativa dos parâmetros. Os resultados mostram que a ferramenta desenvolvida pode ser muito útil para o estudo da relação chuva-vazão em bacias hidrográficas de pequeno porte.

Nos últimos anos os modelos hidrológicos distribuídos vêm ganhando espaço por permitirem que a variabilidade espacial das características das bacias hidrográficas seja incorporada no processo de transformação chuva-vazão. Porém, devido a essa capacidade, os modelos distribuídos tendem a ser matematicamente complexos, impondo que muitos parâmetros sejam medidos ou estimados. Apesar de a literatura apresentar diversos trabalhos que tentem verificar o nível de detalhamento mais adequado à representação dos diversos sistemas, as conclusões são contraditórias, mostrando que há necessidade de estudos mais aprofundados. O presente trabalho propõe e avalia diferentes níveis de detalhamento na representação da bacia hidrográfica do Córrego do Gregório, na cidade de São Carlos, SP, submetida aos processos hidrológicos intervenientes na transformação chuva-vazão, empregando o modelo hidrológico Storm Water Management Model - SWMM. A calibração dos eventos, necessária a adequação dos parâmetros do modelo, utilizou como ferramenta os algoritmos genéticos, produzindo resultados satisfatórios, com coeficientes de eficiência de Nash e Sutfliffe (1970) entre 0,74 e 0,87, variáveis de evento para evento. De uma forma geral, os resultados obtidos com a análise dos diferentes níveis de detalhe evidenciaram a importância da consideração da micro-drenagem na representação dos sistemas. Para os eventos mais freqüentes submetidos à análise quanto maior o detalhe imposto na representação da bacia, maior a velocidade de escoamento resultante da baixa rugosidade das galerias pluviais, e, portanto, maiores vazões de pico foram encontradas. Os resultados ressaltaram também a influência das áreas impermeáveis sobre os hidrogramas, ratificando a importância da determinação criteriosa desse parâmetro. / For the last years, the distributed hydrological models have been recognized by allowing the incorporation of the spatial variability of catchment characteristics for rainfall-runoff simulation. However, due to this ability, the distributed models tend to be mathematically complex and to require many parameters to be measured or estimated. Although the literature presents several works that attempt to ascertain the level of discretization more appropriate to represent the various systems, the results are contradictory, showing the need for further studies. This work proposes and evaluates different levels of representation of the watershed of the Gregory Creek in the city of São Carlos, SP, under rainfall-runoff simulation, by applying the hydrologic model Storm Water Management Model - SWMM. The calibration of the events, needed to adequacy the model parameters, used as tool the genetic algorithm, producing satisfactory results, with values of Nash and Sutcliffe (1970) efficiency coefficients ranging between 0,74 and 0,87, varying from event to event . In general, the results showed the importance of considering the micro-drainage in the systems representation. For more frequent events, by increasing the level of catchment representation, the velocity of flow became greater, resulted from the low roughness of the conduits, and, therefore, higher peak flows rates were found. The results also emphasized the influence of the impervious areas on the hydrographs, confirming the great importance of careful determination of this parameter.

A long record of daily data is used to study the lake levels of Lake Neusiedl, a large steppe lake at the eastern border of Austria. Daily lake level changes are modeled as functions of precipitation, temperature, and wind conditions. The occurrence and the amount of daily precipitation are modeled with logistic regressions and generalized linear models.

In 1910, Paris experienced its biggest flood in the 20th century. In 2010, for the anniversary of this event – supposed to happen every 100 years ! – the flood prediction model that is now used on the Seine basin was tested on its simulation,… and failed to reproduce the observed flood volume. This paper will try to explain, and correct, such disappointing results. Many hypotheses have been tested and based on their results, it has been decided to develop a frost module in order to assess the influence of this phenomenon – that is not taken into account by the lumped hydrological model that is used – on the flood formation. A soil temperature model using air temperature as input data was also designed because soil temperature data were not available in 1910. The addition of the frost module did not, however, bring many improvements to the 1910 flood simulation because frost is a too rare phenomenon on the Seine basin for the module to be correctly calibrated. However, new perspectives are presented to continue the research on this phenomenon.

Evapotranspiration (ET) is an essential component of water cycle as it is an interlinkage between atmosphere, vegetation and soil surface in terms of energy and water balance. However, whether potential ET has the same tendency to change as actual ET and how ET trend (based on the difference between precipitation and runoff) is directly driven by dominant meteorological factors alone or combined with ecosystem‘s feedbacks to climate change (like land-use change) is still under the discussion. In this report, five ET parameterizations within two rainfall-runoff models [Coupled Heat and Mass Transfer Model (CoupModel) and Hydrologiska Byråns Vattenbalansavdelning (HBV)] have been set up based on six subcatchments of Sweden. The scenario derived from CoupModel shows that the trend of ET is affected by the change of land-use, where soil evaporation tends to shift to transpiration and interception evaporation. However, HBV model produces the other scenario: the trend of ET is merely the consequence of meteorological factors. Increased ET is contributed by increased interception evaporation due to the increased precipitation. After identifying the time split of changing ET trends, a dynamic simulation constructed both from HBV and CoupModel indicate that the increased total ET is primarily from increased ET in winter time. More and more interceptive water loss and transpiration resulted from land-use change due to more vegetation. On the other hand, land-use change is also a feed back to climate change. Transpiration controlled by the mechanism of stomata and water uptake controlled by reduction of soil moisture is highly related to variations of climatic conditions.

京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第18620号 / 情博第544号 / 新制||情||96(附属図書館) / 31520 / 京都大学大学院情報学研究科社会情報学専攻 / (主査)教授 多々納 裕一, 教授 矢守 克也, 教授 堀 智晴 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM

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