Dissertations / Theses on the topic 'Rainfall-runoff'
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Riverso, Carlo. "Calibration of rainfall-runoff models." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amslaurea.unibo.it/2619/.
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Abushandi, Eyad. "Rainfall-runoff modeling in arid areas." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2011. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-68530.
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The Wadi Dhuliel catchment/ North east Jordan, as any other arid area has distinctive hydrological features with limited water resources. The hydrological regime is characterized by high variability of temporal and spatial rainfall distributions, flash floods, absence of base flow, and high rates of evapotranspiration. The aim of this Ph.D. thesis was to apply lumped and distributed models to simulate stream flow in the Wadi Dhuliel arid catchment. Intensive research was done to estimate the spatial and temporal rainfall distributions using remote sensing. Because most rainfall-runoff models were undertaken for other climatic zones, an attempt was made to study limitations and challenges and improve rainfall-runoff modeling in arid areas in general and for the Wadi Dhuliel in particular.
The thesis is divided into three hierarchically ordered research topics. In the first part and research paper, the metric conceptual IHACRES model was applied to daily and storm events time scales, including data from 19 runoff events during the period 1986-1992. The IHACRES model was extended for snowfall in order to cope with such extreme events. The performance of the IHACRES model on daily data was rather poor while the performance on the storm events scale shows a good agreement between observed and simulated streamflow. The modeled outputs were expected to be sensitive when the observed flood was relatively small. The optimum parameter values were influenced by the length of a time series used for calibration and event specific changes.
In the second research paper, the Global Satellite Mapping of Precipitation (GSMaP_MVK+) dataset was used to evaluate the precipitation rates over the Wadi Dhuliel arid catchment for the period from January 2003 to March 2008. Due to the scarcity of the ground rain gauge network, the detailed structure of the rainfall distribution was inadequate, so an independent from interpolation techniques was used. Three meteorological stations and six rain gauges were used to adjust and compare with GSMaP_MVK+ estimates. Comparisons between GSMaP_MVK+ measurements and ground rain gauge records show distinct regions of correlation, as well as areas where GSMaP_MVK+ systematically over- and underestimated ground rain gauge records. A multiple linear regression (MLR) model was used to derive the relationship between rainfall and GSMaP_MVK+ in conjunction with temperature, relative humidity, and wind speed. The MLR equations were defined for the three meteorological stations. The ‘best’ fit of the MLR model for each station was chosen and used to interpolate a multiscale temporal and spatial distribution. Results show that the rainfall distribution over the Wadi Dhuliel is characterized by clear west-east and north-south gradients. Estimates from the monthly MLR model were more reliable than estimates obtained using daily data. The adjusted GSMaP_MVK+ dataset performed well in capturing the spatial patterns of the rainfall at monthly and annual time scales, while daily estimation showed some weakness for light and moderate storms.
In the third research paper, the HEC-HMS and IHACRES rainfall runoff models were applied to simulate a single streamflow event in the Wadi Dhuliel catchment that occurred in 30-31.01.2008. Both models are considered suitable for arid conditions. The HEC-HMS model application was done in conjunction with the HEC-GeoHMS extension in ArcView 3.3. Streamflow estimation was performed on hourly data. The aim of this study was to develop a new framework of rainfall-runoff model applications in arid catchment by integrating a re-adjusted satellite derived rainfall dataset (GSMaP_MVK+) to determine the location of the rainfall storm. Each model has its own input data sets. HEC-HMS input data include soil type, land use/land cover map, and slope map. IHACRES input data sets include hourly rainfall and temperature. The model was calibrated and validated using observed stream flow data collected from Al-Za’atari discharge station. IHACRES shows some weaknesses, while the flow comparison between the calibrated streamflow results agrees well with the observed streamflow data of the HEC-HMS model. The Nash-Sutcliffe efficiency (Ef) for both models was 0.51, and 0.88 respectively. The application of HEC-HMS model in this study is considered to be satisfactory.
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Al-Qurashi, Aisha Mufti Al-Sayyid Hassan. "Rainfall-runoff modelling in arid areas." Thesis, Imperial College London, 2008. http://hdl.handle.net/10044/1/8860.
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Arid areas have distinctive hydrological features substantially different from those of humid areas. The high temporal and spatial distribution of the ra;infall, flash floods, absence of base flow, sparsity of plant cover, high transmission losses, high amounts of evaporation and evapotranspiration and the general climatologies are examples of such differences. The aim of this Ph.D. research is to use advanced tools of model analysis to test some of the current models that consider arid area hydrological characteristics. As most models were mainly developed for other regions, an attempt is made to study their limitations using Omani hydrological data, providing some guidelines for improved rainfall-runoff modelling in arid areas in general and Oman in particular. Two different types of models were selected for this research; KINEROS, which is an event based, semi-distributed, physically-based model that is considered suitable to be used for arid area conditions, and, which is continuous, lumped, conceptual model. Two Omani catchments were selected to test the performance of the selected models and to identify the main uncertainties arising, to provide some recommendations regarding the suitability of these models or model types and how they might be improved, to highlight any further data that is required, and how uncertainties should be handled in model applications.
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Loague, Keith M. "An assessment of rainfall-runoff modeling methodology." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/27131.
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This study reports model performance calculations for three event-based rainfall-runoff models on both real and synthetic data sets. The models include a regression model, a unit hydrograph model and a quasi-physically based model. The real data sets are for small upland catchments from the Washita River Experimental Watershed, Oklahoma; the Mahantango Creek Experimental Watershed, Pennsylvania; and the Hubbard Brook Experimental Forest, New Hampshire. The synthetic data sets are generated with a stochastic-conceptual rainfall-runoff simulator. Model performance is assessed for a verification period that is carefully distinguished from the calibration period. Performance assessment was carried out both in forecasting mode and in prediction mode. The results on the real data sets show surprisingly poor forecasting efficiencies for all models on all data sets. The unit hydrograph model and the quasi-physically based model have little forecasting power; the regression model is marginally better. The performance of the models in prediction mode is better. The regression model and the unit hydrograph model showed acceptable predictive power, but the quasi-physically based model produced acceptable predictions on only one of the three catchments. The performance of the regression and unit hydrograph models, in both forecasting and prediction modes, for synthetic data is much better than for the real catchments. The performance of the quasi-physically based model on a synthetic data set is surprisingly poor. Supplemental data gathered from the Oklahoma catchment was used for a spatial variability analysis of steady-state infiltration rates. These data were then used to re-excite the quasi-physically based model; the new information resulted in improved model performance. The concept of space-time tradeoffs across the hydrologic data sets of competing models is introduced and tested. Results show the existence of space-time tradeoffs within model data sets but not across model data sets. It is the belief of the author that the primary barrier to successful application of physically based models in the field lies in the scale problems that are associated with the unmeasurable spatial variability of rainfall and soil hydraulic properties. The fact that simpler, less data intensive models provided as good or better predictions than a physically based model is food for thought. The model evaluation and space-time tradeoff experiments reported in this study are conceptually linked to data-worth analysis, network-design, and model-choice criteria for future studies.Graduate and Postdoctoral Studies
Graduate
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Hawkins, Richard H. "A Taxonomy of Small Watershed Rainfall-Runoff." Arizona-Nevada Academy of Science, 1990. http://hdl.handle.net/10150/296444.
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From the Proceedings of the 1990 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 21, 1990, Arizona State University, Tempe, ArizonaA study of over 11,000 event rainfall and associated direct runoff events from 100 small watersheds was done, in a search for distinct patterns of runoff response and/or association with land type. The results show unexpected variety in the geometry and scale of the rainfall -runoff response. Groupings of similar response type and magnitude were made, and the associations with vegetative cover were tested. Five separate response groups were identified as follows: 1) Inactive, characterized by no recorded responses to any rainstorm in an extended period of record; 2) Complacent, characterized by a very small part of the rainfall (ca 0.1 to 3 percent) being converted to direct runoff, often as a linear response; 3) Standard behavior, the expected "textbook" response common to agricultural lands and humid sites, and in which the runoff slope increases with increasing rainfall, and the scale of runoff far exceeds the complacent response; 4) Violent behavior, in which an abstraction threshold of 2 -6 cm clearly precedes a sudden high response; and 5) Abrupt response in which a very high portion of the rainfall is converted to event runoff without appreciable abstraction, as typified by extensively urbanized drainages. The responses and the group identifications were parameterized by a simple broken -line linear rainfall-runoff equation, and a dichotomous key based on coefficient values is proposed. Only mild associations between response type or coefficient values and the four vegetative covers (Forest, Range, Agriculture, and Urban) were found. The variety of hydrologic behavior on forested watersheds encompassed that of the other three land types.
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Grabau, Matthew R., Richard H. Hawkins, Kevin E. Verweire, and Donald C. Slack. "Variety of Antecedent Runoff Conditions for Rainfall-Runoff with the Curve Number Method." Arizona-Nevada Academy of Science, 2009. http://hdl.handle.net/10150/296695.
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Lee, Hyo Sang. "Regionalisation of rainfall-runoff models in the UK." Thesis, Imperial College London, 2006. http://hdl.handle.net/10044/1/8147.
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Freer, James E. "Uncertainty and calibration of conceptual rainfall runoff models." Thesis, Lancaster University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266810.
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Karlsson, Magnus Sven. "NEAREST NEIGHBOR REGRESSION ESTIMATORS IN RAINFALL-RUNOFF FORECASTING." Diss., The University of Arizona, 1985. http://hdl.handle.net/10150/282088.
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The subject of this study is rainfall-runoff forecasting and flood warning. Denote by (X(t),Y(t)) a sequence of equally spaced bivariate random variables representing rainfall and runoff, respectively. A flood is said to occur at time period (n + 1) if Y(n + 1) > T where T is a fixed number. The main task of flood warning is that of deciding whether or not to issue a flood alarm for the time period n + 1 on the basis of the past observations of rainfall and runoff up to and including time n. With each decision, warning or no warning, there is a certain probability of an error (false alarm or no alarm). Using notions from classical decision theory, the optimal solution is the decision that minimizes Bayes risk. In Chapter 1 a more precise definition of flood warning will be given. A critical review (Chapter 2) of classical methods for forecasting used in hydrology reveals that these methods are not adequate for flood warning and similar types of decision problems unless certain Gaussian assumptions are satisfied. The purpose of this study is to investigate the application of a nonparametric technique referred to as the k-nearest neighbor (k-NN) methods to flood warning and least squares forecasting. The motivation of this method stems from recent results in statistics which extends nonparametric methods for inferring regression functions in a time series setting. Assuming that the rainfall-runoff process can be cast in the framework of Markov processes then, with some additional assumptions, the k-NN technique will provide estimates that converge with an optimal rate to the correct decision function. With this in mind, and assuming that our assumptions are valid, then we can claim that this method will, as the historical record grows, provide the best possible estimate in the sense that no other method can do better. A detailed description of the k-NN estmator is provided along with a scheme for calibration. In the final chapters, the forecasts of this new method are compared with the forecasts of several other methods commonly used in hydrology, on both real and simulated data.
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Goyen, Allan. "Spatial and temporal effects on urban rainfall/runoff modeling." Online version, 2000. http://hdl.handle.net/2100/626.
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University of Technology, Sydney. Faculty of Engineering.Although extensive worldwide literature on urban stormwater runoff exists, very few publications describe runoff development in terms of its basic building blocks or processes and their individual and accumulative significance in response to varying inputs and boundary conditions. Process algorithms should respond accurately to varying input magnitudes and characteristics as well as to changes in antecedent conditions. The present state of estimation errors involved in many current numerical simulation techniques has been reviewed in this thesis. A significant amount of errors that are presently encountered for have been explained in terms of undefined process response not explicitly included within many modelling methodologies. Extensive field monitoring of intra-catchment rainfall and runoff within an urban catchment at Giralang in Canberra, which is typical of Australian urban catchments, was carried out over a 3-year period to define and measure individual runoff processes. This monitoring work led to a greater understanding of the processes driving the aggregation of local runoff from many sub-areas into the runoff observed at full catchment scale. The results from the monitoring process prompted a number of approaches to potentially reduce standard errors of estimate from model-attributable errors based on improvements to definable catchment response mechanisms. The research isolated a number of basic building blocks associated with typical residential allotments, that can be grouped into roof drainage, yard drainage and adjacent road drainage. A proposed modelling approach was developed that allowed these building blocks at an allotment scale to be simply computed using storage routing techniques. This then aggregated via the total catchment’s public drainage system isochronal characteristics utilising a “process tree” approach to provide full catchment scale runoff response. The potential reduction in estimation errors utilising the developed procedure was assessed using a large number of recorded events from the Giralang catchment monitoring data. The proposed numerical modelling approach was found to provide significant improvements over current methods and offered a scale-independent and stormindependent methodology to model catchments of any size without the need for changes to any of the runoff routing parameters. Additionally the approach permits the flexible sequencing and inclusion of a wide range of different urban drainage structures within a catchment that are representative of the local characteristics. The developed procedure also includes a spatially varied water balance approach to infiltration estimation that is more suited to future continuous simulation models. The developed “flexible process tree” approach provides an important step forward in the numerical modelling of complex urban drainage systems. This can reduce errors of estimate by improving intra-catchment process representation.
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Hundecha, Hirpa Yeshewatesfa. "Regionalization of parameters of a conceptual rainfall-runoff model." Stuttgart : Inst. für Wasserbau, 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=975655469.
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Fionda, Alexander Peter Anthony. "Rainfall-runoff model application in ungauged catchments in Scotland." Thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-162181.
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The conceptual rainfall-runoff model Hysim is used to estimate the flow in ungauged catchments in Scotland by Scottish Water. However, there are non-quantified uncertainties associated with the outcomes of the modelling strategy used. In order to identify and quantify these uncertainties it was necessary to use the framework of proxy-basin validation in order to evaluate the performance of different modelling strategies. The proxy-basin validation test requires hydrologically analogous catchments for the evaluation of models, a Region Of Influence regionalisation method was used in order group selected catchments by Q95(%MF). Four groups of four catchments were established, which covered Q95(%MF) 5-7%, 7-9%, 9-11% and 11-13%. The allocation of “donor catchment” and “target catchment” for each Q95(%MF) group was accomplished through discussion with Scottish Water with respect to existing Scottish Water modelled catchments. A single donor catchment and three target catchments were therefore indicated for each group. Two modelling strategies were developed by the study; the first full transposition method used the entire optimised parameter-set from the donor catchment with the exception of the target catchment’s “catchment area” parameter. The second partial transposition method used the entire optimal parameter-set with the exception of the target catchment’s “interception storage”, “time to peak”, “rooting depth” and “catchment area” parameters. It was found that the full transposition method had the least uncertainty associated its use for flow estimation when the parameter-set was derived from a donor catchment calibration that was excellent. Contrarily, it was found that the partial transposition model method had the least uncertainty associated with flow estimation for parameter-sets that were derived from a relatively poor donor catchment calibration. Encouraged by this testing framework, this study has suggested the use of catalogue of donor parameter-sets that can be used to estimate flow for catchments that are hydrologically similar. This strategy of hydrological modelling has been recommended to improve existing Scottish Water Hysim methodology.
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McKillop, Robert. "Modelling the rainfall-runoff response from a headwater wetland." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq21368.pdf.
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Hundecha, Hirpa Yeshewatesfa. "Regionalization of parameters of a conceptual rainfall-runoff model." Stuttgart Inst. für Wasserbau, 2004. http://deposit.d-nb.de/cgi-bin/dokserv?idn=975655469.
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Ndiritu, John G. "An improved genetic algorithm for rainfall-runoff model calibration /." Title page, contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09PH/09phn337.pdf.
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Smith, Paul James. "Probabilistic flood forecasting using a distributed rainfall-runoff model." 京都大学 (Kyoto University), 2006. http://hdl.handle.net/2433/143966.
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Kyoto University (京都大学)0048
新制・課程博士
博士(工学)
甲第12267号
工博第2596号
新制||工||1366(附属図書館)
24103
UT51-2006-J260
京都大学大学院工学研究科都市社会工学専攻
(主査)教授 小尻 利治, 教授 池淵 周一, 教授 中北 英一
学位規則第4条第1項該当
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Tecle, Aregai, Paul Heinrich, John Leeper, and Jolene Tallsalt-Robertson. "Rainfall-Runoff Model for Black Creek Watershed, Navajo Nation." Arizona-Nevada Academy of Science, 2012. http://hdl.handle.net/10150/301297.
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From the Proceedings of the 2012 Meetings of the Hydrology Section - Arizona-Nevada Academy of Science - April 14,2012, Glendale Community College, Glendale, ArizonaThis paper develops a rainfall-runoff model for estimating surface and peak flow rates from precipitation storm events on the Black Creek watershed in the Navajo Nation. The Black Creek watershed lies in the southern part of the Navajo Nation between the Defiance Plateau on the west and the Chuska Mountains on the east. The area is in the semiarid part of the Colorado Plateau on which there is about 10 inches of precipitation a year. We have two main purposes for embarking on the study. One is to determine the amount of runoff and peak flow rate generated from rainfall storm events falling on the 655 square mile watershed and the second is to provide the Navajo Nation with a method for estimating water yield and peak flow in the absence of adequate data. Two models, Watershed Modeling System (WMS) and the Hydrologic Engineering Center (HEC) Hydrological Modeling System (HMS) that have Geographic Information System (GIS) capabilities are used to generate stream hydrographs. The latter show peak flow rates and total amounts of stream flows produced from rainfall storm events. Two 24-hour rainfall amounts, 1.1 inches and 0.6 inches, are imputed into the WMS and HEC HMS modeling system and evaluated to produce 1770 cfs and 3.9 cfs of peak flows and 1106.5 acre feet and 2.7 acre feet of total flow volumes, respectively. Even though the first one seems to be a little high compared to historical peak flows from the watershed, the outcomes seem to be quite appropriate for the study area when compared with gauging site flows at other times as well as with flows from well-instrumented nearby watersheds.
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Pokhrel, Prafulla. "TOWARDS IMPROVED IDENTIFICATION OF SPATIALLY-DISTRIBUTED RAINFALL RUNOFF MODELS." Diss., The University of Arizona, 2010. http://hdl.handle.net/10150/194356.
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Distributed rainfall runoff hydrologic models can be highly effective in improving flood forecasting capabilities at ungauged, interior locations of the watershed. However, their implementation in operational decision-making is hindered by the high dimensionality of the state-parameter space and by lack of methods/understanding on how to properly exploit and incorporate available spatio-temporal information about the system. This dissertation is composed of a sequence of five studies, whose overall goal is to improve understanding on problems relating to parameter identifiability in distributed models and to develop methodologies for their calibration.The first study proposes and investigates an approach for calibrating catchment scale distributed rainfall-runoff models using conventionally available data. The process, called regularization, uses spatial information about soils and land-use that is embedded in prior parameter estimates (Koren et al. 2000) and knowledge of watershed characteristics, to constrain and reduce the dimensionality of the feasible parameter space.The methodology is further extended in the second and third studies to improve extraction of `hydrologically relevant' information from the observed streamflow hydrograph. Hydrological relevance is provided by using signature measures (Yilmaz et al 2008) that correspond to major watershed functions. While the second study applies a manual selection procedure to constrain parameter sets from the subset of post calibrated solutions, the third develops an automatic procedure based on a penalty function optimization approach.The fourth paper investigates the relative impact of using the commonly used multiplier approach to distributed model calibration, in comparison with other spatial regularization strategies and also includes investigations on whether calibration to data at the catchment outlet can provide improved performance at interior locations. The model calibration study conducted for three mid sized catchments in the US led to the important finding that basin outlet hydrographs might not generally contain information regarding spatial variability of the parameters, and that calibration of the overall mean of the spatially distributed parameter fields may be sufficient for flow forecasting at the outlet. This then was the motivation for the fifth paper which investigates to what degree the spatial characteristics of parameter and rainfall fields can be observable in catchment outlet hydrographs.
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Hernandez, Tatiana X. "Rainfall-Runoff Modeling in Humid Shallow Water Table Environments." Scholar Commons, 2001. https://scholarcommons.usf.edu/etd/1537.
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Simulating the processes of rainfall and runoff are at the core of hydrologic modeling. Geomorphologic features, rainfall variability, soil types, and water table depths strongly influence hydrological process in Florida ecosystems. Topographic characteristics of the terrain define the stream paths and landscape. Alteration of these characteristics as a result of urban and/or agricultural developments, for example, can highly influence wetlands and river basin response. There are two predominant landforms in Florida: wetlands, where Variable Saturated Areas form near streams causing saturation excess runoff, and uplands where runoff is mainly generated by infiltration excess. The objective of this work is to analyze the impacts of geomorphologic and hydrologic characteristics on runoff mechanisms in humid environments such as Florida. In general, most research at the hillslope scale use hypothetical values of rainfall, sometimes non-realistic values, and single slope forms to explain the geomorphic and hydrologic process on Variable Saturated Areas. In this thesis, the complexity of hillslope processes on actual Florida topography is assessed by coupling a Digital Elevation Model with a two-dimensional variable saturated-unsaturated flow model called HYDRUS-2D. Actual rainfall records and soil parameters from the Characterization Data for Selected Florida Soils, Soil Survey were used to evaluate hydrologic impacts. A commercial software package, River Tools was used to display and extract topographic information from the Digital Elevation Models.
Results show that when inflitration excess runoff is dominant, infiltration and runoff are very sensitive to time resolution, especially for convective storms. When saturation excess occurs, runoff is not affected by rainfall intensity. However, saturated hydraulic conductivity, depth to the water table, slope and curvature highly influence the extent of Variable Saturated Areas. Results indicate runoff in shallow water table environments is produced mainly by subsurface storm runoff, running below the surface, except in hillslopes with concave curvature and mild slopes. Additionally, concave hillslopes generate more saturation excess runoff than straight and convex hillslopes.
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Michaud, Jene Diane. "RAINFALL-RUNOFF MODELING OF FLASH FLOODS IN SEMI-ARID WATERSHEDS." Department of Hydrology and Water Resources, University of Arizona (Tucson, AZ), 1992. http://hdl.handle.net/10150/614156.
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Flash floods caused by localized thunderstorms are a natural hazard
of the semi -arid Southwest, and many communities have responded by
installing ALERT flood forecasting systems. This study explored a
rainfall- runoff modeling approach thought to be appropriate for
forecasting in such watersheds. The kinematic model KINEROS was
evaluated because it is a distributed model developed specifically for
desert regions, and can be applied to basins without historic data.
This study examined the accuracy of KINEROS under data constraints
that are typical of semi -arid ALERT watersheds. The model was validated
at the 150 km2, semi -arid Walnut Gulch experimental watershed. Under the
conditions examined, KINEROS provided poor simulations of runoff volume
and peak flow, but good simulations of time to peak. For peak flows, the
standard error of estimate was nearly 100% of the observed mean.
Surprisingly, when model parameters were based only on measurable
watershed properties, simulated peak flows were as accurate as when
parameters were calibrated on some historic data. The accuracy of
KINEROS was compared to that of the SCS model. When calibrated, a
distributed SCS model with a simple channel loss component was as
accurate as KINEROS.
Reasons for poor simulations were investigated by examining a)
rainfall sampling errors, b) model sensitivity and dynamics, and c)
trends in simulation accuracy. The cause of poor simulations was divided
between rainfall sampling errors and other problems. It was found that
when raingage densities are on the order of 1/20 km2, rainfall sampling errors preclude the consistent and reliable simulation of runoff from
localized thunderstorms. Even when rainfall errors were minimized,
accuracy of simulations were still poor. Good results, however, have
been obtained with KINEROS on small watersheds; the problem is not
KINEROS itself but its application at larger scales.
The study also examined the hydrology of thunderstorm -generated
floods at Walnut Gulch. The space -time dynamics of rainfall and runoff
were characterized and found to be of fundamental importance. Hillslope
infiltration was found to exert a dominant control on runoff, although
flow hydraulics, channel losses, and initial soil moisture are also
important. Watershed response was found to be nonlinear.
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Donnelly, Lauren. "Comparison of rainfall-runoff modelling techniques in small forested catchments." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq24122.pdf.
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Pechlivanidis, Ilias. "The significance of spatial variability of rainfall on runoff generation." Thesis, Imperial College London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.508445.
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Orellana, Bobadilla Barbara A. "Identification of lumped and semi-distributed conceptual rainfall runoff models." Thesis, Imperial College London, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.590036.
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Conceptual rainfall runoff (CRR) models usually require calibration to identify their parameter values, whereas their model structure is selected prior to modelling. Consid- erable efforts have been directed into calibration of lumped CRR models. Identification of the model structure on the basis of available data still remains unclear. The data-based mechanistic (DBM) approach does minimal assumptions of the model structure, which is identified using powerful statistic techniques. Moreover, there is a similarity between the CRR and DBM model.formulations. Based on this similarity, an integration of CRR and DBM models is proposed and evaluated. Two calibration strategies are investigated in the Upper Illinois river catchment (USA) for lumped modelling. Results show that the identi- fied TF model improves the simulated flow, especially in the time to peak, in comparison to the modelled flow of the conceptual model. It is suggested that this improvement is di- rectly related to the lag time parameter considered in the TF model between the effective rainfall and the flow. Semi-distributed rainfall runoff models provide advantages over lumped models in representing the effect of spatially variable inputs, outputs and catchment properties. However they are affected by parameter identifiability. Four calibration strategies are considered to analyse the ability to meaningful simulate flow at interior locations. Results show that there are no significant improvements at the catchment outlet when internal gauges are included. The behavioural parameter sets defined at the catchment outlet tend to be non-behavioural at the internal gauges. This tendency increases with the distance from the catchment outlet to the internal gauges. Considering only spatial variability of rainfall rather than also of parameter values did not improve the simulations at the out- let or at the internal gauges, compared to lumped modelling results. Calibration only at the catchment outlet using independent sampling of the internal subcatchments achieved similar results. Identification of lumped and semi-distributed CRR models is carried out using the RRTMSD modelling toolbox developed for this work.
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Young, Andrew Richard. "Regionalising a daily rainfall runoff model within the United Kingdom." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340664.
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Reed, Seann Mischa. "Use of digital soil maps in a rainfall-runoff model /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
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DeBano, Leonard F., and Malchus B. Jr Baker. "Runoff and Erosion from Hydrophobic Forest Soils During Simulated Rainfall." Arizona-Nevada Academy of Science, 1998. http://hdl.handle.net/10150/296500.
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Sumner, Neil R. "Calibration of a conceptual rainfall-runoff model using simulated annealing." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 1995. https://ro.ecu.edu.au/theses/1169.
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Simulated annealing (Kirkpatrick et al, 1983) is used to estimate the parameters of a mathematical model that predicts the water yield from a catchment. The calibration problem involves finding the global minimum of a multivariate function that has many extraneous local minima, a situation in which conventional optimisation methods are ineffective. The objective function which quantifies discrepancies between the computed and observed streamflows must be carefully selected to satisfy the least square assumptions. Several published simulated annealing algorithms have been implemented, tested and evaluated using standard test functions. Appropriate cooling schedules are found for each algorithm and test function investigated. The number of function evaluations required to find the minimum is compared to published results for the test functions using either simulated annealing and other global optimisation methods. A new simulated annealing algorithm based on the Hooke and Jeeves (1961) pattern search method is developed and compared with existing algorithms from the literature.
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Rezaur, Rahman Bhuiyan. "Studies on interrill sediment delivery and rainfall kinetic energy." Thesis, Click to view the E-thesis via HKUTO, 1999. http://sunzi.lib.hku.hk/hkuto/record/B42575631.
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Thapa, Pawan Kumar. "Physically based spatially distributed rainfall runoff modelling for soil erosion estimation." Stuttgart Inst. für Wasserbau, 2010. http://d-nb.info/1002459923/34.
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Hadley, Jennifer Lyn. "Near real-time runoff estimation using spatially distributed radar rainfall data." Thesis, Texas A&M University, 2003. http://hdl.handle.net/1969.1/346.
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The purpose of this study was to evaluate variations of the Natural Resources Conservation Service (NRCS) curve number (CN) method for estimating near real-time runoff for naturalized flow, using high resolution radar rainfall data for watersheds in various agro-climatic regions of Texas. The CN method is an empirical method for calculating surface runoff which has been tested on various systems over a period of several years. Many of the findings of previous studies indicate the need to develop variations of this method to account for regional and seasonal changes in weather patterns and land cover that might affect runoff. This study seeks to address these issues, as well as the inherent spatial variability of rainfall, in order to develop a means of predicting runoff in near real-time for water resource management. In the past, raingauge networks have provided data for hydrologic models. However, these networks are generally unable to provide data in real-time or capture the spatial variability associated with rainfall. Radar networks, such as the Next Generation Weather Radar (NEXRAD) of the National Weather Service (NWS), which are widely available and continue to improve in quality and resolution, can accomplish these tasks. In general, a statistical comparison of the raingauge and NEXRAD data, where both were available, shows that the radar data is as representative of observed rainfall as raingauge data. In this study, watersheds of mostly homogenous land cover and naturalized flow were used as study areas. Findings indicate that the use of a dry antecedent moisture condition CN value and an initial abstraction (Ia) coefficient of 0.1 produced statistically significant results for eight out of the ten watersheds tested. The urban watershed used in this study produced more significant results with the use of the traditional 0.2 Ia coefficient. The predicted results before and during the growing season, in general, more closely agreed with the observed runoff than those after the growing season. The overall results can be further improved by altering the CN values to account for seasonal vegetation changes, conducting field verification of land cover condition, and using bias-corrected NEXRAD rainfall data.
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Sulistiyono, Heri. "Rainfall-runoff model calibration using experimental designs and response surface methodology." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0001/MQ42452.pdf.
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Cooper, Vincent A. "On automatic calibration of conceptual rainfall runoff models using optimisation techniques." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=38473.
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Conceptual rainfall runoff (CRR) models are popular among hydrologists owing to their modest input data requirements, their simple structure and therefore their modest computational requirements. The realisation that CRR model calibration is more akin to a global optimisation problem, not a local optimisation one, was a significant development. The subsequent applications of global optimisation methods (GOM) have solved a major difficulty for estimating model parameters. Further improvement in parameter estimation may follow if constraints that help to limit the number of feasible parameter values can be developed. This study has proposed a methodology for formulating constraints related to the CRR model structure and the hydrologic data available for calibration.For developing this methodology, the research examined the capabilities of three GOMs for calibration, namely, the Shuffled Complex Evolution (SCE) method, a genetic algorithm (GA) and a simulated annealing procedure (SA), and one local optimisation method, the downhill simplex method (DSM). The GOMs all performed better than the DSM. The SCE displayed superior accuracy and robustness for synthetic data applications, being able to find all (five) selected sets of parameter values with almost 100% accuracy. However, the GA performed better than the SCE method with real data and perhaps reflects some weakness in the SCE to find global optimal points under difficult calibration conditions. The SA was inferior to the others with both types of data applications.
The importance of selection of parameter ranges is currently given little attention in the calibration process, but even with the superior search capability of GOMs, inflated search spaces can frustrate their searches and may lead to inferior parameter estimation. Several inequalities relating model parameters with the hydrologic data were developed, which when coupled with the SCE method, significantly improved the GOM performance. This modified SCE method appeared less sensitive to the problem of parameter range specification. A method for formulating these constraints was demonstrated on synthetic data and a procedure for its application to real data was done using data from two tropical watersheds.
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Vongtanaboon, Sukanya. "Parsimonious modelling the rainfall-runoff behaviour of large catchments in Thailand." Thesis, Lancaster University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.421974.
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There is currently great concern in Thailand about the effects of land-use and climate change on the rainfall-runoff behaviour of the great rivers in Thailand. At the same time, hydrologists are becoming increasingly worried about uncertainties in the forecasts of physics-based models - due to the complexity of their structures and inappropriateness of the catchment characteristics incorporated. These concerns become particularly acute when such models are applied to large river catchments (100 - 10,000 km2) - the scales needed to link hydrological research with land-use management and planning.Within this thesis, the value of using parsimonious models (i. e., structurally very simple with few parameters but a high simulation efficiency), Normally restricted to engineering applications, is addressed. The particular modelling techniques used form part of new suite of tools known as Data-Based-Mechanistic (DBM) modelling. Three very large catchments, one in northern Thailand, one in the centre and one in the south were the focus for the study and each contained one or more smaller catchments. The results of the DBM modelling showed that much of the rainfall-runoff dynamics of these large catchments could be modelled with very simple (3 or 4-parameter) models and that these parameters were related to the catchment size, hydrogeology and climatic regime. The role of the climate was shown with the DBM tool known as the Dynamic Harmonic Regression (DHR) model. These new methods were complemented by traditional hydrological engineering analyses, which supported the findings of the DBM. Indeed, these traditional techniques clearly showed the effect of rapid and extensive urbanisation on catchment hydrology. In an attempt to show how such parsimonious methods might be extended to incorporate additional information, where it can be justified, catchment topographic analyses were compared with measured catchment moisture measurements. The poor performance of the topographic model evaluated did, however, mean that further validation work needs to be undertaken before this particular topographic model should be applied (without similar testing) throughout Thailand. Given the greater use of physics-based models of catchment systems in Thailand, this work demonstrates that parsimonious statistical approaches remain of great value to the interpretation of hydrological processes operating within large Thai catchments, and indeed to the identification of changes in these processes with land-use and climate change.
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Zhang, Yanlong. "Calibration of physically-based distributed rainfall-runoff model with radar data." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/37760.
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Birkel, Christian. "Integrating high-resolution tracer data into lumped conceptual rainfall-runoff models." Thesis, University of Aberdeen, 2010. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=202563.
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Environmental change is currently regarded as one of the greatest threats to water resources. Limited knowledge of hydrological processes prevents from adequate characterization of systems behaviour to future changes. Geochemical and isotope tracers are considered reliable tools to study physical processes, but tracer studies are often constrained by the temporal and spatial variability in the tracer response and coarse data sets. Novel automatic sampling devices and inexpensive laser spectroscopy made higher-resolution stable isotope tracer data feasible. This thesis presents approaches to integrate geochemical tracer data, high-resolution stable isotope tracer data and process dynamics observed in the field into lumped conceptual rainfall-runoff models to study catchment hydrological processes at different scales. The use of such process-based data successfully aided model conceptualization and calibration in the quest for simple water and solute transport models with improved representation of process dynamics. In particular, high-resolution isotope data could identify temporally and spatially variable flow pathways to assess diffuse pollution transport, which otherwise might have been lost. This work showed that pollutants in some catchments are likely to rapidly discharge into the stream and due to geological properties reside over longer periods in deeper groundwater systems. In other words, changes to these systems today are likely to show an immediate effect fading persistently over decadal time periods. Such knowledge is important if catchment remediation and recovery has to be assessed from a management point of view such as for example targeting measures and cost-effective land management to improve water quality status.
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Wagener, Thorsten. "Identification of parsimonious rainfall-runoff models for gauged and ungauged catchments." Thesis, Imperial College London, 2002. http://hdl.handle.net/10044/1/10278.
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Rainfall-runoff models are indispensable tools in most hydrological studies. However, the identification of appropriate models remains a difficult problem despite decades of research. This dissertation analyses the identification of conceptual, parsimonious (which may be best translated as parameter efficient), lumped continuous models for gauged and ungauged catchments. The emphasis of this study lies on review and development of new methodologies, not so much on extensive applications. Though different investigative examples of how these new approaches can be applied are shown and a limited case study is provided. A modelling toolkit has been developed after an extensive review of current model structures and modelling procedures. It consists of two components, a Rainfall-Runoff Modelling (RRMT) and a Monte Carlo Analysis Toolbox (MGAT). These allow for the quick implementation and evaluation of rainfall-runoff model structures, although the latter has much more general applicability. The review of local modelling procedures, i.e. applicable to gauged catchments, has lead to the analysis and further development of multi-objective procedures for model performance and identifiability analysis. A novel DYNamic Identifiability Analysis (DYNIA) methodology has been developed which, amongst other things, can be used to analyse inadequacies in a model structure. Both approaches are combined in a framework of corroboration and rejection which can be applied to any dynamic mathematical model structure. This local procedure is extended to the regional case, i.e. applicable to ungauged catchments. Regional information about model parameters is used to derive statistical relationships with catchment characteristics. Various approaches are discussed and analysed. The most promising techniques, combined with new ways of considering uncertainty in the regional modelling process, are integrated in a regional modelling framework. Both frameworks are applied in a case study to 23 catchments located in the Thames river basin in the UK, which have a particularly wide range of geologies.
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Green, Daniel. "Understanding urban rainfall-runoff responses using physical and numerical modelling approaches." Thesis, Loughborough University, 2018. https://dspace.lboro.ac.uk/2134/33530.
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This thesis provides a novel investigation into rainfall-runoff processes occurring within a unique two-tiered depth-driven overland flow physical modelling environment, as well as within a numerical model context where parameterisation and DEM/building resolution influences have been investigated using an innovative de-coupled methodology. Two approaches to simulating urban rainfall-runoff responses were used. Firstly, a novel, 9 m2 physical modelling environment consisting of a: (i) a low-cost rainfall simulator component able to simulate consistent, uniformly distributed rainfall events of varying duration and intensity, and; (ii) a modular plot surface layer was used. Secondly, a numerical hydroinundation model (FloodMap2D-HydroInundation) was used to simulate a short-duration, high intensity surface water flood event (28th June 2012, Loughborough University campus). The physical model showed sensitivities to a number of meteorological and terrestrial factors. Results demonstrated intuitive model sensitivity to increasing the intensity and duration of rainfall, resulting in higher peak discharges and larger outflow volumes at the model outflow unit, as well as increases in the water depth within the physical model plot surface. Increases in percentage permeability were also shown to alter outflow flood hydrograph shape, volume, magnitude and timing due to storages within the physical model plot. Thus, a reduction in the overall volume of water received at the outflow hydrograph and a decrease in the peak of the flood event was observed with an increase in permeability coverage. Increases in the density of buildings resulted in a more rapid receding limb of the hydrograph and a steeper rising limb, suggesting a more rapid hydrological response. This indicates that buildings can have a channelling influence on surface water flows as well as a blockage effect. The layout and distribution of permeable elements was also shown to affect the rainfall-runoff response recorded at the model outflow, with downstream concentrated permeability resulting in statistically different hydrograph outflow data, but the layout of buildings was not seen to result in significant changes to the outflow flood hydrographs; outflow hydrographs appeared to only be influenced by the actual quantity and density of buildings, rather than their spatial distribution and placement within the catchment. Parameterisation of hydraulic (roughness) and hydrological (drainage rate, infiltration and evapotranspiration) model variables, and the influence of mesh resolution of elevation and building elements on surface water inundation outputs, both at the global and local level, were studied. Further, the viability of crowdsourced approaches to provide external model validation data in conjunction with dGPS water depth data was assessed. Parameterisation demonstrated that drainage rate changes within the expected range of parameter values resulted in considerable losses from the numerical model domain at global and local scales. Further, the model was also shown to be moderately sensitive to hydraulic conductivity and roughness parameterisation at both scales of analysis. Conversely, the parameterisation of evapotranspiration demonstrated that the model was largely insensitive to any changes of evapotranspiration rates at the global and local scales. Detailed analyses at the hotspot level were critical to calibrate and validate the numerical model, as well as allowing small-scale variations to be understood using at-a-point hydrograph assessments. A localised analysis was shown to be especially important to identify the effects of resolution changes in the DEM and buildings which were shown to be spatially dependent on the density, presence, size and geometry of buildings within the study site. The resolution of the topographic elements of a DEM were also shown to be crucial in altering the flood characteristics at the global and localised hotspot levels. A novel de-coupled investigation of the elevation and building components of the DEM in a strategic matrix of scenarios was used to understand the independent influence of building and topographic mesh resolution effects on surface water flood outputs. Notably, the inclusion of buildings on a DEM surface was shown to have a considerable influence on the distribution of flood waters through time (regardless of resolution), with the exclusion of buildings from the DEM grid being shown to produce less accurate results than altering the overall resolution of the horizontal DEM grid cells. This suggests that future surface water flood studies should focus on the inclusion and representation of buildings and structural features present on the DEM surface as these have a crucial role in modifying rainfall-runoff responses. Focus on building representation was shown to be more vital than concentrating on advances in the horizontal resolution of the grid cells which make up a DEM, as a DEM resolution of 2 m was shown to be sufficiently detailed to conduct the urban surface water flood modelling undertaken, supporting previous inundation research.
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Kapangaziwiri, Evison. "Revised parameter estimation methods for the Pitman monthly rainfall-runoff model." Thesis, Rhodes University, 2008. http://hdl.handle.net/10962/d1006172.
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In recent years, increased demands have been placed on hydrologists to find the most effective methods of making predictions of hydrologic variables in ungauged basins. A huge part of the southern African region is ungauged and, in gauged basins, the extent to which observed flows represent natural flows is unknown, given unquantified upstream activities. The need to exploit water resources for social and economic development, considered in the light of water scarcity forecasts for the region, makes the reliable quantification of water resources a priority. Contemporary approaches to the problem of hydrological prediction in ungauged basins in the region have relied heavily on calibration against a limited gauged streamflow database and somewhat subjective parameter regionalizations using areas of assumed hydrological similarity. The reliance of these approaches on limited historical records, often of dubious quality, introduces uncertainty in water resources decisions. Thus, it is necessary to develop methods of estimating model parameters that are less reliant on calibration. This thesis addresses the question of whether physical basin properties and the role they play in runoff generation processes can be used directly in the estimation of parameter values of the Pitman monthly rainfall-runoff model. A physically-based approach to estimating the soil moisture accounting and runoff parameters of a conceptual, monthly time-step rainfall-runoff model is proposed. The study investigates the physical meaning of the model parameters, establishes linkages between parameter values and basin physical properties and develops relationships and equations for estimating the parameters taking into account the spatial and temporal scales used in typical model applications. The estimationmethods are then tested in selected gauged basins in southern Africa and the results of model simulations evaluated against historical observed flows. The results of 71 basins chosen from the southern African region suggest that it is possible to directly estimate hydrologically relevant parameters for the Pitman model from physical basin attributes. For South Africa, the statistical and visual fit of the simulations using the revised parameters were at least as good as the current regional sets, albeit the parameter sets being different. In the other countries where no regionalized parameter sets currently exist, simulations were equally good. The availability, within the southern African region, of the appropriate physical basin data and the disparities in the spatial scales and the levels of detail of the data currently available were identified as potential sources of uncertainty. GIS and remote sensing technologies and a widespread use of this revised approach are expected to facilitate access to these data.
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Famiglietti, James Stephen 1960. "Threshold structures in conceptual rainfall-runoff models : potential problems with calibration." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/191912.
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One of the most frequently reported problems in the automatic calibration of conceptual rainfall-runoff (CRR) models is the inability to identify a unique and conceptually realistic parameter set for a model in use on a particular watershed. Sorooshian and Gupta [1983,1985] and Gupta and Sorooshian [1983] have shown that model structure can be largely responsible for this problem. This thesis extends this work by further investigating calibration problems resulting from model structure, particularly when the CRR model contains one or more threshold elements. Two aspects of this problem were addressed. In the first, the practice of modeling nonlinear processes with linear models is analyzed. In the second, reparameterization techniques to improve parameter identifiability (Gupta and Sorooshian [1983]; Sorooshian and Gupta [1985]) are demonstrated on a four-parameter simplified CRR model. The results of these studies show that the parameter identification procedure can in fact be hindered by model structure and that the interdependence of model structure and parameter estimation methodologies must be considered by CRR model users and developers if automatic calibration is to be successful.
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Luckemeier, Richard Ewald 1948. "A rainfall-runoff model for an urban watershed in Tucson, Arizona." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277165.
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The U.S. Geological Survey and the City of Tucson, Arizona, have been collecting rainfall and runoff data on several watersheds in the Tucson area for several years. Among the purposes of this project is to use the data to test rainfall-runoff models in an effort to find one to successfully simulate flood flows in Tucson. One such model, the Distributed Routing Rainfall-Runoff Model (DR3M), was tested using data collected on Rob Wash in Tucson. It was found DR3M performs about as well as it does in other parts of the United States, although it tends to underestimate flood flows for large storms and overestimate flows for smaller storms. Unique features with regard to the hydrology of urban Tucson require special attention when using DR3M; these features are associated with the nature of dry washes and summer rainfall in Tucson. Experience indicates DR3M is not truly a deterministic model.
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Neri, Mattia <1990>. "Innovative methodologies for enhancing the regionalisation of rainfall-runoff model parameters." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amsdottorato.unibo.it/9858/1/PhDThesis_NeriMattia_final.pdf.
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The present research work focuses on the regionalisation of rainfall-runoff model parameters, fundamental for the implementation of hydrological models in ungauged basins and needed to reproduce the actual sequence of river discharge in time. Regionalisation of parameters is based on the transfer of information from hydrologically similar gauged basins to ungauged basins. This work provides further insights on parameter regionalisation and catchment similarity through the application of innovative methodologies to support the existing knowledge.
The first experiment develops a methodology to test the robustness of regionalisation procedures to the availability of data in the study region. In particular, the effect of the density of streamflow gauging stations and the topological relationships between their corresponding drainage basins on the different regionalisation techniques is investigated. Such work provides useful information for the choice of the most appropriate method, based on data availability in the region.
The focus is then moved to the value of hydrological similarity at sub-basin scale. Driven by the fact that similarity is generally defined between entire catchments, neglecting some significant differences in the within-basin rainfall-runoff transformation processes, a methodology to differentiate hydrological processes at sub-basin scale and to transfer model parameters from similar sub-basins is proposed. The analysis is based on the diversification of the parameter values, and therefore of the corresponding hydrological dynamics, across elevation, one of the main factors influencing the runoff generation processes.
Finally, an innovative catchment signature is proposed for improving our knowledge about hydrological similarity, meant for the delineation of hydrologically similar regions. A new methodology for identifying the dominant rainfall-runoff transformation dynamics is presented: the interaction between the entire time-series of runoff generation forcings and runoff itself is quantified taking advantage of the concepts of the Information Theory and used to characterise catchments with promising results.
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Chen, Chia-Jung, and 陳嘉榮. "A Study on Regional Rainfall Analysis and Rainfall-Runoff Forecasting." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/53250698604048877126.
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博士國立成功大學
水利及海洋工程學系
88
This thesis aims to study hydrological design and hydrological forecasting, which are important subjects in water resource engineering. Three parts including regional IDF analysis, rainfall and runoff forecasting are respectively investigated. The results of both hydrological design and forecast in this study are expected to predict the risk of hydraulic structure during typhoon period. The first part of this thesis attempts to develop the regional IDF analysis for ungauged site, which is common problem in hydrological design. Rainfall records from 38 stations in Northern Taiwan provide the data set to develop regional rainfall intensity formula using regional analysis method. This work classifies the Northern Taiwan into three homogeneous regions, which can respond the characteristic of climate and topography on each region. The dimensionless rainfall intensity-duration-frequency (IDF) curves are then established in each homogeneous region. The parameters of dimensionless IDF curve can be regionalizied to generate the regional rainfall intensity-duration-frequency formula, which can reasonably simulate the IDF relationship at ungauged site from the results of calibration and verification. The uncertainty analysis of regional IDF formulae are further investigated based on the method of mean first order second moment (MFOSM). This work reveals that the IDF relationship estimated by using the distribution of extreme value type I can be located into the 95% confidence intervals of uncertainty analysis of regional IDF formula. In the hydrological forecasting, the main purpose of the second part is to study rainfall forecasting during the typhoon period, including a long-term (24 hours ahead) and a short-term (3 hours ahead) rainfall forecast models separately. The long-term forecasting model attempts to forecast 24 hours rainfall hyetograph for a typhoon based on optimal 24 hours rainfall pattern decision and 24 hours rainfall depth prediction. Optimal rainfall pattern for a typhoon is decided based on both typhoon characteristics and historical databases of various rainfall patterns. The databases for four rainfall patterns of Huff are first generated from historical rainfall storm of typhoon events by using fuzzy classification method. The typhoon characteristics including central pressure, central velocity, cyclonic radius and moving path are chosen as variables to decide optimal rainfall pattern for a typhoon approaching to Taiwan by using fuzzy multi-object decision method. 24 hours rainfall depth is further statistically and dynamically predicted by using typhoon characteristic including typhoon path (central position, moving direction) , central pressure, central velocity and cyclonic radius as decision-making variables. The calibration results conclude that the proposed model can reasonably forecast 24 hours rainfall hyetograph for a typhoon event. Regarding to the short-term rainfall forecast model, 3 hours ahead rainfall is forecasted based on both grey system theory and one-time step forecasting technique. The model parameters are calibrated by using fuzzy goal regression. A grey rainfall-runoff model is developed in the third part of this thesis. The model can provide 1~4 hours ahead runoff forecasting in union with rainfall forecasting model developed in the second part. An error prediction model proposed in this study is found to be useful for updating the forecasting results.
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Hsu, Shih-Jiun, and 徐士鈞. "Rainfall Runoff Model for Green Roof." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/6qqjtn.
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碩士國立臺灣海洋大學
河海工程學系
102
The great mass of green land in urban areas has been turned into impermeable pavement due to rapid urbanization in recent years. It has disturbed the urban hydrologic system resulting in urban flood problem which can’t be solved by traditional methods such as building storm water sewerage system, building detention/retention ponds, etc. Therefore, the new wave of Low Impact Development (LID) techniques have been advocated in recent years in US and other western countries to mitigate non-point source pollutants and storm water in urban areas. Green roof is one of the techniques used in LID but research in the effectiveness in flood mitigation is rare in Taiwan The purpose of this study is to establish a hydrologic model to simulate the relationship between rainfall and runoff for green roof. The model is an event and physical model. Interception of plant, Green Ampt infiltration mechanism, media properties, storage capacity of drainage board, and other parameters have been considered in the model. Major parameters in the model are calibrated by observed data. The calculation procedures of the model are programmed using Microsoft Office Excel language. In the study, an experimental extensive type green roof with surface area of 3.2 m2 (L=2.0m x W=1.6 m), 1% in slope angle, 20cm of medium depth, covering with plant named Eremochloa Ophiuroides is set up on the roof of No. 2 Building, Department of Harbor and River Engineering, National Taiwan Ocean University. Also a meteorological station is set up near the green roof for measuring climatic data including rainfall, wind speed, radiation, and temperature. Observation period started from January 2014. Seven rainfall events are measured to the end of June 2014. Three events are for parameters calibration and four for verification. The sensitivity analysis is carried for two major parameters (initial moisture content and hydraulic conductivity). Results show that hydraulic conductivity will only influence the moving speed within medium not runoff and initial moisture content is the major influential factor to runoff. In the verification, average difference for peak flow between measured and simulated values is 2.2% and 1.1% for average total runoff volume. If we compare the hydrologic condition between before and after green roof is set up, peak flow is reduced 88.1% and 88.9% for total runoff volume. The model established in this study can effectively describe the rainfall-runoff relationship. Also green roof has significant effectiveness in mitigating storm water for low return period rainfall.
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Lin, Yuan-Peng, and 林元鵬. "Stochastic Analysis in Rainfall-Runoff Modelling." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/11388016613307399550.
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碩士國立臺灣大學
土木工程研究所
81
Rainfall-runoff models are essential for the management of watersheds. However,the uncertainties of the hydrlogic phenomena and the modelling process result in inevitable modelling errors which seriously influence the consequent applications. In this study , a simple and dircet methodlogy for uncertainty analysis is developed to estimate the uncertainty of the rainfall-runoff model by means of establishing the stochastic integral equations of model prediction errors . Furthermore , the probabilistic distributions of some criterion variables which are important to hydrologic designs are estimated by using Monte Carlo simulation and Bootstrap Resampling method.
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劉光武. "Studies on distributed rainfall-runoff model." Thesis, 1991. http://ndltd.ncl.edu.tw/handle/01514374952877252683.
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Hsu, Feng-Yuan, and 許峰源. "Support Vector Machines for rainfall-runoff forecasting." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/49326541266217910401.
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碩士國立臺灣大學
土木工程學研究所
96
To yield reliable forecasts of stream flow, a robust flood forecasting model is required. For this purpose, effective flood forecasting models based on the support vector machine (SVM), which is a novel kind of neural networks (NNs), are proposed. Based on statistical learning, SVMs have better generalization ability than back-propagation netwoks (BPNs), which are the most frequently used convectional NNs. In addition, the robustness of SVMs is one of the major advantages over BPNs. However, the robustness of hydrological models has received little attention in literature. To make comparisons between SVMs and BPNs, two kinds of NN-based (SVM-based and BPN-based) forecasting models are constructed to yield one- to five-hour ahead forecasts. Then an application is conducted to clearly demonstrate the advantages of SVMs and representative results are discussed in depth. Firstly, the results show that SVM-based models perform better than BPN-based models for one- to five-hour ahead forecasts. Thus, SVM-based models forecast stream flow more accurately. In addition, the results indicate that the performance of BPN-based models highly depend on four factors: (a) number of training events, (b) selection of training events, (c) noise included in training data and (d) initial weights. On the contrary, the influence of the four factors on the performance of SVM-based models is much less than that of BPN-based models. Hence the performance of SVM-based models is more reliable than that of BPN-based models. In conclusion, the SVM-based models are much more accurate and robust than BPN-based models. The proposed SVM-based models are recommended as an alternative to the existing models because of their accuracy and robustness.
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Liang, Jia-wei, and 梁家瑋. "Building The Rainfall-Runoff System By Knowledge Engineering." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/34765163504260273716.
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碩士逢甲大學
水利工程所
95
Because the terrain of Taiwan is precipitous, the rain tendency is centralized and the river flows urgently short. The regional rainfall that makes is influenced by topography greatly. The rainfall is combined by many kinds of factors. It also influence by time and space. For the complicated and nonlinearity system, statistics method and physics method both are difficult to effective treatment. Carry on the way to predict to the hydrological data after presenting many kinds of artificial intelligence field. But because a great characteristic of artificial intelligence, so long as can solve the problem, with the accumulative total of time and materials, every way can reach the good result. How to reduce resources and waste of time is the way to compare quality. This research tries to combine artificial intelligence with knowledge engineering. According to six major stages of knowledge engineering, design one artificial intelligence system and construct the prediction model in rainfall-runoff. Build the prediction way in which by the artificial intelligence system. BPN comes to deal with to nonlinearity of the relation. Knowledge system cooperate with Euclidean distance conduct comparing with the time of dealing with the way. And try to revise the uncertainty of solving with the fuzzy theory. With validation tests at Wu-Xi watershed, the models get good prove of results. In two kinds of common methods used treatment rainfall. It also can get good result without change models’ structure.
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Yan, Shih-Wei, and 顏世偉. "Application of Combined Forecasts on Rainfall-Runoff Simulation." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/55976415052697051260.
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博士國立中興大學
土木工程學系所
102
Objective selection and tradeoffs have always been key central issues in rainfall-runoff models. In general, precision for high and low flows cannot be achieved or considered concurrently. Combination forecasts are potentially capable of producing more suitable or superior results through appropriate methods. In this study, we propose an automatic method, a runoff-scale weighting method （RSWM）, to solve issues regarding flow precision trade-offs. Objective functions that emphasize precision at various flows were used to conduct combination forecasts and validate the effectiveness of this method. The results indicated that combination forecasting is capable of improving precision during all flow stages to further enhance model effectiveness. In addition, we used the fuzzy multi-objective function simple-average (FMOF-SA) and fuzzy multi-objective function-low (FMOF-low) as reference flows to test the robustness of parameters to determine whether the RSWM is affected by reference flows. The results indicated that the FMOF-low is relatively more robust than the FMOF-SA, although both had only a slight influence on the final results. According to the final results, the mean absolute relative residual(MARR) of most flow stages is approximately 0.2, which shows that the RSWM can be applied to various runoff conditions. The proposed RSWM could combine several models and effectively improve both the traditional single objective function (such as RMSE and MPE) and the FMOF-neutral. However, further efforts are suggested to compare the RSWM with other multi-objective functions, and to apply the RSWM to other multi-objective functions.
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Cheng-ChunChang and 張正群. "Developing Unit Hydrograph With Comprehensive Rainfall-Runoff Simulation." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/46884453008381872132.
Full textAbstract:
碩士國立成功大學
水利及海洋工程學系
105
Because of the special geographical location, geologic conditions, and climatic conditions of Taiwan, we require an accurate rainfall-runoff model to handle the preceding operations of water resources planning and hydraulic engineering at the catchment. Nonetheless, to construct a rational rainfall-runoff model, we should concern the accuracy and reasonableness of the in-situ observational data. Take the typhoon-flood events happened at Zengwun reservoir catchment as an example, there were lots of large scale events’ runoff coefficients over 1. Actually, the underestimation of the observed precipitation and the overestimation of the streamflow could give rise to the events’runoff coefficients over 1. According to the in-situ experiences, during the typhoon-flood events period, the reason of underestimated precipitation could be attributed to the errors of the rainfall measurements at rainfall gauge stations. On the other hand, the landslide of catchment and the scour of torrent could contribute to the watershed outflow containing amounts of sediment which lead to the overestimation of the observed outflow. The aforementioned factors and uncertainties have impacts on estimating more accurate outflow at the catchment. Consequently, we have to consider all of the above-mentioned factors into the process of analyzing rainfall-runoff model. For the sake of assessing effective rainfall and direct runoff meticulously to develop double unit hydrograph, this study simulates the comprehensive rainfall-runoff process at the catchment which includes the compensating for the probable-underestimated rainfall hourly, applying the suspended load rating curve to estimate the sediment inflow into the reservoir, and simulating the subsurface flow with single tank model. Furthermore, in order to simulate the peak discharge more effectively, we adopt the double unit hydrograph to conduct the simulation. Meanwhile, we apply the trust-region reflective newton method to optimum every undetermined parameters in the calibration. Apply above mentioned method into typhoon-flood events at Zengwun reservoir catchment, we could obtain the heavy-rain unit hydrograph with base period 8 hours as well as light-rain unit hydrograph with base period 16 hours. The result demonstrates that the simulated streamflow are closed to the observed streamflow highly once containing comprehensive rainfall-runoff process in the simulated procedure and adopting double unit hydrograph. The integral coefficient efficiency (CE) of the calibration cases is 0.87 and the CE in validation cases are from 0.89 to 0.94. In addition, it could simulate the peak discharge precisely and the average percent error of peak discharge (EQP) is -0.3 %. In a nutshell, it could build a proper double unit hydrograph to forecast the streamflow yielded form the precipitation in the future once it contained the comprehensive rainfall-runoff process in the modelling.
50
Yang, Tao-Chang, and 楊道昌. "A Study on Regional Continuous Rainfall-Runoff Model." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/85487936370820245663.
Full textAbstract:
博士國立成功大學
水利及海洋工程學系
87
ABSTRACT The theme aims at developing a strategy for calibrating a continuous rainfall-runoff model at ungauged catchments, in which water resource projects may be planned and the flow series can be simulated at the early stage of planning. Two major parts are included in the study. To improve the performance of a continuous rainfall-runoff model at gauged catchments is the first part to be investigated. The second part is to develop a strategy for model calibration at ungauged catchments by utilizing the results of the former. The HBV hydrological model, broadly used in Europe, was employed in the study and slightly modified for successful application in the Gao-Pen Creek Basin. Since the model parameters should be calibrated with objective functions, the first part of this study detected the effects of model calibration results by using various objective functions, including the root mean square error (RMSE), mean absolute percentage error (MPE), and multi-stage mean absolute percentage error (MSMPE). It concluded that using RMSE and MPE emphasized the high-flow and low-flow simulations, respectively. The MSMPE was found to simultaneously simulate all flow ranges well. Since various flow stages can be considered as various objectives, respectively, the study combined the concepts of the multi-objective programming and the fuzzy set theory to develop a fuzzy multi-objective function. The other subjects were further discussed in the study, which included (1) effects on the internal mechanisms of hydrological models by using various objective functions, (2) modification of model parameters for simultaneously simulating high and low flows, and (3) development of an error correction method on the basis of the fuzzy logic controller, which had a well performance for error correction outside the calibration period. Before regionalizing the parameters of rainfall-runoff model, the sensitivities and interaction of parameters should be detected for further understanding. The study evaluated the interaction of parameters based on the entropy theory and found that the parameters for controlling soil moisture accounting had extreme interaction one another. It implies that it''s hard to find a representative parameter set for a basin and make the regionalization of parameters difficult. Based on the above study results, the second part of this study developed a calibration strategy for a continuous rainfall-runoff model at ungauged catchments. This strategy differs to the traditional one, which relates the model parameters and catchment characteristics at gauge catchments for extrapolating the model parameters to ungauged catchments. In the strategy of the study, the regional flow duration curve was first constructed by which synthetic flow duration curves for ungauged catchments were calculated. The objective functions based on fitting synthetic flow duration curves were then used for model calibration at ungauged catchments. Two catchments in the basin of Gao-Ping Creek were used to verify the calibration strategy. It concluded that the strategy could calibrate the model parameters reasonably and the flow series could be simulated well at ungauged catchments.