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A research report submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science in Engineering, 2017 / The main problem to be investigated is how short duration data records can be augmented using existing data from nearby catchments with data with long periods of record. The purpose of the investigation is to establish a method of improving hydrological data using data from a gauged catchment to improve data from an ungauged catchment. The investigation is undertaken using rainfall data for catchments in Lesotho. Marginal distributions describing the annual maximum rainfall for the catchments, and a joint distribution of pairs of catchments were established. The parameters of these distributions were estimated using the Bayesian – Markov Chain Monte Carlo approach, and using both the single-site (univariate) estimation and the two-site (bivariate) estimations. The results of the analyses show that for catchments with data with short periods of record, the precision of the estimated location and scale parameters improved when the estimates were carried out using the two-site (bivariate) method. Rainfall events predicted using bivariate analyses parameters were generally higher than the univariate analyses parameters. From the results, it can be concluded that the two-site approach can be used to improve the precision of the rainfall predictions for catchments with data with short periods of record. This method can be used in practice by hydrologists and design engineers to enhance available data for use in designs and assessments. / CK2018

O presente trabalho envolveu o projeto e construção de um amostrador seqüencial automático de chuva considerando a deposição úmida. Para isso, o amostrador seqüencial fornece um volume escolhido em função de análises químicas previamente estabelecidas. O amostrador seqüencial faz a coleta da deposição úmida, que é a chuva precipitada sobre um coletor inicialmente tampado. Este procedimento adotado é de fundamental importância para a avaliação das condições de poluição presentes na atmosfera. Através deste amostrador seqüencial, também é possível determinar a intensidade da chuva para o evento considerado, ou seja, é possível avaliar se a chuva precipitada é forte ou fraca. O planejamento do amostrador seqüencial automático de chuva foi baseado em diversos amostradores encontrados na literatura, os quais visavam o monitoramento para diferentes objetivos. O processo de desenvolvimento e construção foi bem sucedido, uma vez que todas as fases foram executadas de modo que o processo de coleta das amostras ocorreu com sucesso. Foram coletados alguns ventos de chuva possibilitando estimar as respectivas intensidades pluviométricas, ou seja, avaliar para o campo considerado qual foi o tipo de chuva, se foi forte ou fraca. Para uma coleta específica, o amostrador foi exposto a um evento de chuva muito intenso, funcionando conforme o esperado. Os registros foram 290 ml de volume de amostra, coletados em uma área de 1230 cm2, em um tempo de 1,12 min apresentando intensidade de 2,1 mm/min. Esse resultado indica um valor muito alto de intensidade. / The present work involved the design and construction of an automatic sequential rainfall sampler, with the goal of evaluating the quality of rainfall water. For such, the sequential sampler supplies a chosen volume taking into account the chemical analysis previously defined. The sequential sampler performs the collection of humid deposition, which is the precipitated rain that falls on a collector initially covered. This adopted procedure is of fundamental importance for the evaluation of the pollution conditions present in the atmosphere. Through this sequential sampler, it is also possible to define the rainfall intensity for the event considered, i.e., it is possible to evaluate if the precipitated rain is heavy or light. The planning of the automatic sequential rainfall sampler was based on several samplers found in the literature, which \'aimed the monitoring due to different goals. The design and construction processes were successful, once all the phases were performed and the sample collection process occurred with success. Some events were collected and their respective pluviometric intensities were measured, i.e., evaluate for the considered time which was the rain type, if it was heavy or light. For a specific collection the sampler was exposed to a very intense event of rain, working as expected. The records were 290 of sample volume, collected in an area of 1230 cm2 during a period of 1.12 min, with intensity of 2.1 mm/min. This result indicate a value of very high intensity.

Accuracy in estimation of precipitation can be achieved by utilizing the combination of spatial radar reflectivity data (Z) and the high resolution temporal rain gage based rainfall data (R). The study proposes the use of optimization models for optimizing the Z-R coefficients and exponents for different storm types and seasons. Precipitation data based on reflectivity, collected from National Climatic Data Center (NCDC) and rain gage data from Southwest Florida Water Management District (SWFWMD) over same temporal resolutions were analyzed using the Rain-Radar- Retrieval (R3) system developed as a part of the study. Optimization formulations are proposed to obtain optimal coefficients and exponents in the Z-R relationships for different seasons and objective selection of storm-type specific Z-R relationships. Different approaches in selection of rain gage stations and selection of events for optimization are proposed using gradient based solver and genetic algorithms. / Kandarp Pattani. / Thesis (M.S.C.S.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.\

by Sin Tak Wah. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1981. / Bibliography: leaves 208-215.

Wong Chun Kit. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves [132-143]). / Abstracts in English and Chinese. / List of Tables --- p.i / List of Figures --- p.iv / List of Symbols --- p.v / Chapter CHAPTER ONE: --- INTRODUCTION --- p.1 / Chapter 1.1 --- Objectives and Significance of the Study --- p.4 / Chapter 1.2 --- Physical Setting of Hong Kong --- p.5 / Chapter 1.3 --- Climate of Hong Kong --- p.9 / Chapter 1.4 --- Data Acquisition --- p.11 / Chapter 1.4.1 --- Raingauges in Hong Kong --- p.11 / Chapter 1.4.2. --- Database for the Spatial Variation Analyses --- p.14 / Chapter 1.4.2.1. --- Data Selection for the Analyses for Factors Affecting Rainfall ´ؤ Elevation and Aspect --- p.15 / Chapter 1.4.2.2. --- Data Selection for the Classification of Stations and Inter-station Correlation Analysis --- p.17 / Chapter 1.4.3 --- Database for the Temporal Variation Analyses --- p.20 / Chapter CHAPTER TWO : --- LITERATURE REVIEW --- p.22 / Chapter 2.1 --- Spatial Variation of Rainfall --- p.22 / Chapter 2.2 --- Detection of Temporal Changes in Rainfall --- p.28 / Chapter 2.3 --- Urban Influence on Rainfall --- p.29 / Chapter 2.4 --- Studies in Hong Kong --- p.33 / Chapter CHAPTER THREE : --- METHODOLOGY --- p.33 / Chapter 3.1 --- Preliminary Processing of the Data --- p.38 / Chapter 3.2 --- Data Analysis --- p.40 / Chapter 3.2.1 --- General Pattern of Rainfall Distribution --- p.40 / Chapter 3.2.2 --- Data Analyses of Spatial Variation --- p.41 / Chapter 3.2.2.1 --- Correlation between Rainfall and Elevation --- p.41 / Chapter 3.2.2.2 --- Correlation between Rainfall and Aspect --- p.42 / Chapter 3.2.2.3 --- Classification of Stations --- p.43 / Chapter 3.2.2.4 --- Inter-Station Correlation Analysis --- p.46 / Chapter 3.2.3 --- Data Analysis of Temporal Variation --- p.46 / Chapter 3.2.3.1 --- The Running Mean Method --- p.47 / Chapter 3.2.3.2 --- The 'Standard Error of the Difference' Test --- p.49 / Chapter CHAPTER FOUR: --- RESULTS AND DISCUSSION --- p.50 / Chapter 4.1 --- Graphical Representation of Spatial Rainfall Pattern --- p.50 / Chapter 4.1.1 --- Annual Rainfall Pattern --- p.50 / Chapter 4.1.2 --- Monthly Rainfall Pattern --- p.56 / Chapter 4.1.3 --- Frequency Distribution of Raindays --- p.59 / Chapter 4.1.4 --- Pentade Rainfall Pattern --- p.64 / Chapter 4.1.5 --- Diurnal Rainfall Pattern --- p.67 / Chapter 4.1.6 --- Implications of the Spatial Rainfall Pattern --- p.70 / Chapter 4.2 --- Analyses of Spatial Variation in Rainfall --- p.78 / Chapter 4.2.1 --- Relationship between Rainfall and Elevation --- p.78 / Chapter 4.2.2 --- Relationship between Rainfall and Aspect --- p.82 / Chapter 4.2.3 --- Classification of Stations --- p.85 / Chapter 4.2.3.1 --- Principal Components Interpretation --- p.87 / Chapter 4.2.3.2 --- Result of Classification --- p.90 / Chapter 4.2.4 --- Inter-Station Correlation Analysis --- p.98 / Chapter 4.2.5 --- Discussion of the Rainfall Spatial Variation --- p.103 / Chapter 4.3 --- Analyses of Temporal Variation in Rainfall --- p.107 / Chapter 4.3.1 --- Annual Rainfall --- p.107 / Chapter 4.3.2 --- Monthly Rainfall --- p.110 / Chapter 4.3.3 --- Pentade Rainfall --- p.112 / Chapter 4.3.4 --- Diurnal Rainfall --- p.117 / Chapter 4.3.5 --- Discussion of the Rainfall Temporal Variation --- p.118 / Chapter CHAPTER FIVE: --- CONCLUSIONS AND RECOMMENDATIONS --- p.126 / Chapter 5.1 --- Summary of Findings --- p.126 / Chapter 5.2 --- Limitation of this Research --- p.129 / Chapter 5.3 --- Prospects of this Research --- p.130 / Bibliography

O presente trabalho envolveu o projeto e construção de um amostrador seqüencial automático de chuva considerando a deposição úmida. Para isso, o amostrador seqüencial fornece um volume escolhido em função de análises químicas previamente estabelecidas. O amostrador seqüencial faz a coleta da deposição úmida, que é a chuva precipitada sobre um coletor inicialmente tampado. Este procedimento adotado é de fundamental importância para a avaliação das condições de poluição presentes na atmosfera. Através deste amostrador seqüencial, também é possível determinar a intensidade da chuva para o evento considerado, ou seja, é possível avaliar se a chuva precipitada é forte ou fraca. O planejamento do amostrador seqüencial automático de chuva foi baseado em diversos amostradores encontrados na literatura, os quais visavam o monitoramento para diferentes objetivos. O processo de desenvolvimento e construção foi bem sucedido, uma vez que todas as fases foram executadas de modo que o processo de coleta das amostras ocorreu com sucesso. Foram coletados alguns ventos de chuva possibilitando estimar as respectivas intensidades pluviométricas, ou seja, avaliar para o campo considerado qual foi o tipo de chuva, se foi forte ou fraca. Para uma coleta específica, o amostrador foi exposto a um evento de chuva muito intenso, funcionando conforme o esperado. Os registros foram 290 ml de volume de amostra, coletados em uma área de 1230 cm2, em um tempo de 1,12 min apresentando intensidade de 2,1 mm/min. Esse resultado indica um valor muito alto de intensidade. / The present work involved the design and construction of an automatic sequential rainfall sampler, with the goal of evaluating the quality of rainfall water. For such, the sequential sampler supplies a chosen volume taking into account the chemical analysis previously defined. The sequential sampler performs the collection of humid deposition, which is the precipitated rain that falls on a collector initially covered. This adopted procedure is of fundamental importance for the evaluation of the pollution conditions present in the atmosphere. Through this sequential sampler, it is also possible to define the rainfall intensity for the event considered, i.e., it is possible to evaluate if the precipitated rain is heavy or light. The planning of the automatic sequential rainfall sampler was based on several samplers found in the literature, which \'aimed the monitoring due to different goals. The design and construction processes were successful, once all the phases were performed and the sample collection process occurred with success. Some events were collected and their respective pluviometric intensities were measured, i.e., evaluate for the considered time which was the rain type, if it was heavy or light. For a specific collection the sampler was exposed to a very intense event of rain, working as expected. The records were 290 of sample volume, collected in an area of 1230 cm2 during a period of 1.12 min, with intensity of 2.1 mm/min. This result indicate a value of very high intensity.