Spelling suggestions: "subject:"hydrologic models"" "subject:"hyrdrologic models""
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The application of radar measured rainfall to hydrologic modelling /Schell, George Stewart. January 1989 (has links)
The capability of radar measured rainfall to enhance the simulation of storm hydrographs was assessed. Six rainfall events which occurred in 1986 and 1987 over an 8.13 km$ sp2$ agricultural watershed in south-western Quebec were used in model simulations. Radar measured rainfall rates were calibrated using measurements from a single tipping-bucket raingauge located at the study site. / A deterministic, event-based model, HYMO, was used to simulate streamflow using radar and gauge measured rainfall. The model utilized two rainfall abstraction techniques, i.e. the SCS Curve Number method and the Green-Ampt infiltration equation. Simulated streamflow hydrographs were compared with observed storm flows. / For short duration, high intensity, simple rainfall events, there were minor improvements in hydrograph simulations when calibrated radar measured rainfalls were input to the model, compared to tipping-bucket raingauge measurements. Complex, low intensity storms were poorly simulated by the model using either rainfall data source. Neither rainfall abstraction method proved consistently superior.
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Digital terrain modelling of catchment erosion and sedimentation / Hua Sun.Sun, Hua January 1998 (has links)
Corrigenda pasted onto front end-paper. / Bibliography: leaves 307-326. / xvii, 326 leaves : ill., maps ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / A study was undertaken of erosion and sedimentation in a catchment in South Australia. An erosion and sedimentation model was developed and interfaced with the existing digital terrain models called TAPES-C and THALES, to estimate soil erosion and deposition in Sauerbier Creek catchment. / Thesis (Ph.D.)--University of Adelaide, Dept. of Civil and Environmental Engineering, 1999?
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Digital terrain modelling of catchment erosion and sedimentation / Hua Sun.Sun, Hua January 1998 (has links)
Corrigenda pasted onto front end-paper. / Bibliography: leaves 307-326. / xvii, 326 leaves : ill., maps ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / A study was undertaken of erosion and sedimentation in a catchment in South Australia. An erosion and sedimentation model was developed and interfaced with the existing digital terrain models called TAPES-C and THALES, to estimate soil erosion and deposition in Sauerbier Creek catchment. / Thesis (Ph.D.)--University of Adelaide, Dept. of Civil and Environmental Engineering, 1999?
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Identification and modelling of hydrological persistence with hidden Markov modelsWhiting, Julian Peter January 2006 (has links)
Hydrological observations are characterised by wet and dry cycles, a characteristic that is termed hydrological persistence. Interactions between global climate phenomena and the hydrological cycle result in rainfall and streamflow data clustering into wetter and drier states. These states have implications for the management and planning of water resources. Statistical tests constructed from the theory of wet and dry spells indicate that evidence for persistence in monthly observations is more compelling than at an annual scale. This thesis demonstrates that examination of monthly data yields spatially - consistent patterns of persistence across a range of hydrological variables. It is imperative that time series models for rainfall and streamflow replicate the observed fluctuations between the climate regimes. Monthly time series are generally represented with linear models such as ARMA variants ; however simulations from such models may underestimate the magnitude and frequency of persistence. A different approach to modelling these data is to incorporate shifting levels in the broader climate with a tendency to persist within these regimes. Hidden Markov models ( HMMs ) provide a strong conceptual basis for describing hydrological persistence, and are shown to provide accurate descriptions of fluctuating climate states. These models are calibrated here with a full Bayesian approach to quantify parameter uncertainty. A range of novel variations to standard HMMs are introduced, in particular Autoregressive HMMs and hidden semi - Markov models which have rarely been used to model monthly rainfall totals. The former model combines temporal persistence within observations with fluctuations between persistent climate states, and is particularly appropriate for modelling streamflow time series. The latter model extends the modelling capability of HMMs by fitting explicit probability distributions for state durations. These models have received little attention for modelling persistence at monthly scale. A non - parametric ( NP ) HMM, which overcomes the major shortcomings of standard parametric HMMs, is also described. Through removing the requirement to assume parametric forms of conditional distributions prior to model calibration, the innovative NP HMM framework provides an improved estimation of persistence in discrete and continuous data that remains unaffected by incorrect parametric assumptions about the state distributions. Spatially - consistent persistence is identified across Australia with the NP HMM, showing a tendency toward stronger persistence in low-rainfall regions. Coherent signatures of persistence are also identified across time series of total monthly rainfall, numbers of rain - days each month, and the intensities of the most extreme rain events recorded each month over various short durations, illustrating that persistent climate states modulate both the numbers of rain events and the amount of moisture contained within these events. These results provide a new interpretation of the climatic interactions that underlie hydrological persistence. The value of HMMs to water resource management is illustrated with the accurate simulation of a range of hydrologic data, which in each case preserves statistics and spell properties over a range of aggregations. Catchment - scale rainfall for the Warragamba Reservoir is simulated accurately with HMMs, and rainfall - runoff transformations from these simulations provide reservoir inflows of lower drought risk than provided from ARMA models. / Thesis (Ph.D.)--School of Civil and Environmental Engineering, 2006.
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Climate change impacts on the catchment contribution to lake water quantity and quality /Moore, Karen, January 2007 (has links)
Diss. (sammanfattning) Uppsala : Uppsala universitet, 2007. / Härtill 5 uppsatser.
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Risk and reliability assessment of multiple reservoir water supply headworks systems /Crawley, P. D. January 1995 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, 1995. / Includes bibliographical references (p. 474-514).
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Rainfall runoff model improvements incorporating a dynamic wave model and synthetic stream networks /Cui, Gurong. January 1999 (has links)
Thesis (Ph. D.)--University of Newcastle, 1999. / Department of Civil, Surveying and Environmental Engineering. Includes bibliographical references (leaves 246-255). Also available online.
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Quantitative methods for hydrological spatial field comparison /Wealands, Stephen Russell. January 2006 (has links)
Thesis (Ph.D.)--University of Melbourne, Dept. of Civil and Environmental Engineering, 2006. / Typescript. Includes bibliographical references (leaves 223-235).
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The drying of the Luvuvhu River, South Africa distinguishing the roles of dams and land cover change /Griscom, Hannah. January 2007 (has links)
Thesis (M.S.)--University of Wyoming, 2007. / Title from PDF title page (viewed on Nov. 21, 2008). Includes bibliographical references.
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Near real-time runoff estimation using spatially distributed radar rainfall dataHadley, Jennifer Lyn, January 2004 (has links)
Thesis (M.S.)--Texas A & M University, 2003. / "December 2003." Includes bibliographical references (p. 82-85). Also available via the Internet.
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