Download or read book Spatiotemporal Variability of Hydrologic Response written by Aldrich Edra Castillo and published by . This book was released on 2014 with total page 189 pages. Available in PDF, EPUB and Kindle. Book excerpt: Basin hydrologic response pertains to the partitioning of precipitation into stream-flow, evapotranspiration, and change in storage. The ability to explain or predict the response has many applications e.g. flood forecasting, water budget studies, and design of hydrological observing systems. However, explaining the response is challenging because it is the combined manifestation of many complex and interrelated factors that naturally vary in space and time, and act over a variety of scales. A possible key is better understanding of the space-time dynamics of the hydrologic state variable - the soil moisture field. This thesis uses the distributed hydrologic model MOBIDIC that uses a single soil layer with dual compartments: a capillary and a gravity reservoir composed of small, and large pores, respectively. Mass and energy fluxes are simultaneously solved using simple linear equations. These make the model computationally efficient. To improve soil moisture simulations, some model modifications were introduced. MOBIDICs ability to simulate the magnitude range and dynamics of soil moisture at the local scale is found comparable with a benchmark model that uses non-linear soil physics relations. We derive an entropy-based dimensionless measure of hydrologic complexity H which measures the distance of a given soil moisture spatial probability distribution from two limiting cases. Using 8 test basins with area of 10°-103 km2 and representing semiarid, temperate, and humid climates, it is shown that H effectively tracks the evolution of soil moisture distribution, and captures the interplay between vertical and lateral fluxes. Furthermore, we investigate the relationship of W with observable basin attributes and traditional measures of hydrologic response. Clear and logical relationships emerge only after grouping basins based on similarity. For example, in the semiarid basins, H increases with catchment area, infiltration ratio and baseflow index. For basins of similar size, H is highest in temperate climate, consistent with soil moisture being double-bounded so its variability peaks at intermediate conditions. Finally, although not explicitly coded in MOBIDIC, hysteresis is evident in the discharge-storage plots. It emerges from the use of a dual-pore soil structure that captures the threshold behavior of runoff. R- helps in understanding the mechanisms involved.

Download or read book Extreme Hydrology and Climate Variability written by Assefa Melesse and published by Elsevier. This book was released on 2019-07-03 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt: Extreme Hydrology and Climate Variability: Monitoring, Modelling, Adaptation and Mitigation is a compilation of contributions by experts from around the world who discuss extreme hydrology topics, from monitoring, to modeling and management. With extreme climatic and hydrologic events becoming so frequent, this book is a critical source, adding knowledge to the science of extreme hydrology. Topics covered include hydrometeorology monitoring, climate variability and trends, hydrological variability and trends, landscape dynamics, droughts, flood processes, and extreme events management, adaptation and mitigation. Each of the book's chapters provide background and theoretical foundations followed by approaches used and results of the applied studies. This book will be highly used by water resource managers and extreme event researchers who are interested in understanding the processes and teleconnectivity of large-scale climate dynamics and extreme events, predictability, simulation and intervention measures. - Presents datasets used and methods followed to support the findings included, allowing readers to follow these steps in their own research - Provides variable methodological approaches, thus giving the reader multiple hydrological modeling information to use in their work - Includes a variety of case studies, thus making the context of the book relatable to everyday working situations for those studying extreme hydrology - Discusses extreme event management, including adaption and mitigation

Download or read book Influence of Spatial Variability and Scale Effects on the Parameterization of Hydrologic Response written by Eric F. Wood and published by . This book was released on 1987 with total page 578 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hydrological Drought written by Lena M. Tallaksen and published by Elsevier. This book was released on 2004 with total page 626 pages. Available in PDF, EPUB and Kindle. Book excerpt: The majority of the examples are taken from regions where the rivers run most of the year.

Download or read book Climate Variability and Change written by Flow Regimes from International Experimental and Network Data (Project) and published by . This book was released on 2006 with total page 738 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains 117 reviewed papers from over 30 countries, published in English, French and Spanish, which reflect both international dimension of FRIEND and the key challenges facing hydrologists in the 21st century.

Download or read book Hydrologic Variability Within the Climate Regions of Continental United States and Its Teleconnection with Climate Variables written by Balbhadra Thakur and published by . This book was released on 2020 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: The entropy of all systems is supposed to increase with time, this is also observed in the hydroclimatic records as increased variability. The current dissertation is primarily focused on the hydrologic variability of the hydrologic records in the climate regions across Continental United States. The study evaluated the effects of serial correlation in the historical streamflow records on both gradual trend and abrupt shift in streamflow. The study also evaluated the trend before and after the shift occurrence to validate whether the observed changes in streamflow is a result of long-term variability or climate regime shift. Secondly, the current dissertation evaluated the variability within western US hydrology which is highly driven by the oscillation of Pacific Ocean such as El Niño - Southern Oscillation (ENSO). The dissertation evaluated the variability in snow water equivalent (SWE) of western US as the winter snow accumulation of the region drives the spring-summer streamflow in the region which contributes to the major portion of yearly streamflow. The SWE variability during the individual phases of ENSO were analyzed to reveal the detailed influence of ENSO on historic snow accumulations. The study is not solely limited to the hydrologic variability evaluation rather; it also delves into obtaining the time lagged spatiotemporal teleconnections between large scale climate variables and streamflow and forecast the later based on the obtained teleconnections. To accomplish the research goals the current dissertation was subdivided into three research tasks. First task dealt with the streamflow records of 419 unimpaired streamflow records which were grouped into seven climate regions based on National Climate Assessment, to evaluate the regional changes in both seasonal streamflow and yearly streamflow percentiles. Non-parametric Mann-Kendall test and Pettitt's test were utilized to evaluate the streamflow variability as gradual trend and abrupt shift, respectively. Walker test was performed to test the global significance of the streamflow variability within each climate regions based on local trend and shift significance of each streamflow stations. The task also evaluated the presence of serial correlation in the streamflow records and its effects on both trend and shift within the climate regions of continental United States for the first time. Maximum variability in terms of both trend and shift were observed for summer as compared to other seasons. Similarly, greater number of stations showed streamflow variability for 5th and 50th percentile streamflow as compared to 95th and 100th percentile streamflow. It was also observed that serial correlation affected both trend and step while, accounting for the lag-1 autocorrelation improved shift results. The results indicated that the streamflow variability has more likely occurred as shift as compared to the gradual trend. The outcomes of the current result detailing historic variability may help to envision future changes in streamflow. The second task evaluated the spatiotemporal variability of western US SWE over 58 years (1961-2018) as a trend and a shift. The task tested whether the SWE is consistent during ENSO phases utilizing the Kolmogorov - Smirnov (KS) test. Trend analysis was performed on the SWE data of each ENSO phase. Shift analysis was performed in the entire time series of 58 years. Additionally, the trend in the SWE data was evaluated before and after shift years. Mann- Kendal and Pettit's tests were utilized for the detection of trend and shift, respectively. The serial correlation was considered during the trend evaluation, while Thiel-Sen approach was used for the evaluation of the trend magnitude. The serial correlation in time series which is the potential cause of overestimation and underestimation of the trend evaluation was found to be absent in the SWE data. The results suggested a negative trend and a shift during the study period. The negative trend was absent during neutral years and present during El Niño and La Niña years. The trend magnitudes were maximum during La Niña years followed by those during El Niño years and the entire length of the data. It was also observed that if the presence of negative shift in the SWE was considered, then most of the stations did not show a significant trend before and after the occurrence of a shift. The third task forecasted the streamflow at a regional scale within Sacramento San Joaquin (SSJ) River Basin with largescale climate variables. SSJ is an agricultural watershed located in the drought sensitive region of California. The forecast techniques involved a hybrid statistical framework that eliminates the bias resulting from predefined indices at regional scale. The study was performed for eight unimpaired streamflow stations from 1962 to 2016. First, the Singular Valued Decomposition (SVD) teleconnections of the streamflow corresponding to 500 mbar geopotential height, sea surface temperature, 500 mbar specific humidity (SHUM500), and 500 mbar U-wind (U500) were obtained. Second, the skillful SVD teleconnections were screened non-parametrically. Finally, the screened teleconnections were used as the streamflow predictors in the non-linear regression models (K-nearest neighbor regression and data-driven support vector machine). The SVD results identified new spatial regions that have not been included in existing predefined indices. The nonparametric model indicated the teleconnections of SHUM500 and U500 being better streamflow predictors compared to other climate variables. The regression models were capable to apprehend most of the sustained low flows, proving the model to be effective for drought-affected regions. It was also observed that the forecasting approach showed better forecasting skills with preprocessed large-scale climate variables rather than using the predefined indices. The techniques involved in this task was simple, yet robust in providing qualitative streamflow forecasts that may assist water managers in making policy-related decisions when planning and managing watersheds.

Download or read book Hydroclimatology written by Marlyn L. Shelton and published by Cambridge University Press. This book was released on 2009 with total page 439 pages. Available in PDF, EPUB and Kindle. Book excerpt: A graduate textbook on the interdisciplinary significance of hydroclimatology, explaining the relationship between the climate system and the hydrologic cycle.

Download or read book Forecasting Seasonal Hydrologic Response in Major River Basins written by A. M. Tanvir Hossain Bhuiyan and published by . This book was released on 2014 with total page 381 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seasonal precipitation variation due to natural climate variation influences stream flow and the apparent frequency and severity of extreme hydrological conditions such as flood and drought. To study hydrologic response and understand the occurrence of extreme hydrological events, the relevant forcing variables must be identified. This study attempts to assess and quantify the historical occurrence and context of extreme hydrologic flow events and quantify the relation between relevant climate variables. Once identified, the flow data and climate variables are evaluated to identify the primary relationship indicators of hydrologic extreme event occurrence. Existing studies focus on developing basin-scale forecasting techniques based on climate anomalies in El Nino/La Nina episodes linked to global climate. Building on earlier work, the goal of this research is to quantify variations in historical river flows at seasonal temporal-scale, and regional to continental spatial-scale. The work identifies and quantifies runoff variability of major river basins and correlates flow with environmental forcing variables such as El Nino, La Nina, sunspot cycle. These variables are expected to be the primary external natural indicators of inter-annual and inter-seasonal patterns of regional precipitation and river flow. Relations between continental-scale hydrologic flows and external climate variables are evaluated through direct correlations in a seasonal context with environmental phenomenon such as sun spot numbers (SSN), Southern Oscillation Index (SOI), and Pacific Decadal Oscillation (PDO). Methods including stochastic time series analysis and artificial neural networks are developed to represent the seasonal variability evident in the historical records of river flows. River flows are categorized into low, average and high flow levels to evaluate and simulate flow variations under associated climate variable variations. Results demonstrated not any particular method is suited to represent scenarios leading to extreme flow conditions. For selected flow scenarios, the persistence model performance may be comparable to more complex multivariate approaches, and complex methods did not always improve flow estimation. Overall model performance indicates inclusion of river flows and forcing variables on average improve model extreme event forecasting skills. As a means to further refine the flow estimation, an ensemble forecast method is implemented to provide a likelihood-based indication of expected river flow magnitude and variability. Results indicate seasonal flow variations are well-captured in the ensemble range, therefore the ensemble approach can often prove efficient in estimating extreme river flow conditions. The discriminant prediction approach, a probabilistic measure to forecast streamflow, is also adopted to derive model performance. Results show the efficiency of the method in terms of representing uncertainties in the forecasts.

Download or read book Evaporation Under Natural Conditions written by Mikhail Ivanovich Budyko and published by . This book was released on 1963 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Space and Time Scale Variability and Interdependencies in Hydrological Processes written by R. A. Feddes and published by Cambridge University Press. This book was released on 1995-08-24 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the integrated contributions of hydrologists, meteorologists and ecologists to the first IHP/IAHS George Kovacs Colloquium in connection with the study of global hydrology and climate change. The atmospherical, hydrological and terrestrial components of the Earth's systems operate on different time and space scales. Resolving these scaling incongruities, as well as understanding and modelling the complex interaction of land surface processes at the different scales, represent a major challenge for hydrologists, ecologists and meteorological scientists alike. This book deals with time and space scale variations with reference to several topics including: soil water balance; ecosystems and interaction of flow systems; and macroscale hydrological modelling. This book will be of great use to researchers, engineers and forecasters with an interest in space and time scale variability.

Download or read book The Influence of Climate Change and Climatic Variability on the Hydrologic Regime and Water Resources written by International Union of Geodesy and Geophysics. General Assembly and published by [Wallingford, England] : International Association of Hydrological Sciences. This book was released on 1987 with total page 666 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Combining Indirect Observations and Models to Resolve Spatiotemporal Patterns of Precipitation in Complex Terrain written by Brian M. Henn and published by . This book was released on 2015 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mountain precipitation in the Western United States is critical for the water resources of the region, but resolving spatial and temporal patterns of precipitation in complex terrain is challenging due to lack of observations, measurement uncertainty and high spatial variability. We examine several gridded precipitation datasets over the Sierra Nevada mountain range of California, and find that these widely-used products exhibit substantial variation in water-year total precipitation over different areas of the range. In addition, trends in precipitation and snow computed from different datasets vary substantially. Both findings suggest that further work is needed to better resolve spatial and temporal patterns of precipitation in complex terrain. Streamflow observations are widely made and reflect the basin’s hydrologic response to precipitation input. We develop a methodology for inferring basin-mean precipitation using lumped hydrologic models and Bayesian model calibration, which infers water-year total precipitation given daily streamflow observations. We apply this approach to several basins around Yosemite National Park in the Sierra Nevada in order to assess the sensitivity and robustness of inferred precipitation. We find that patterns of precipitation can be inferred from streamflow, both in terms of spatial and year-to-year variability. However, by using a small ensemble of hydrologic model structures to test the sensitivity of inferred precipitation, we also show that the absolute amounts of inferred precipitation are subject to significant uncertainty. Higher-elevation basins of the Sierra Nevada are hydrologically snow-dominated, and we hypothesize that the uncertainty in inferred precipitation can be reduced by calibrating the hydrologic model to both snow and streamflow observations. We leverage the recent availability of a high-resolution distributed snow dataset from the Airborne Snow Observatory (ASO) to determine basin-mean snow water equivalent (SWE) over the upper Tuolumne River basin. We also compare point and distributed SWE measurements over the basin, to assess the reliability of using point measurements to estimate basin-mean SWE. In this case, point measurements show bias in estimating basin-mean ASO SWE, largely due to non-representative sampling with respect to elevation. When basin-mean SWE is included with streamflow in model calibration, uncertainty in inferred precipitation is reduced by up to half, and model ensemble consistency is improved. To resolve patterns of precipitation over the Sierra Nevada, we infer precipitation from streamflow using 56 stream gauges that measure runoff from relatively unimpaired basins, over 1950-2010. We compare inferred precipitation to gauge-based gridded precipitation data, finding that significant differences exist between the mean spatial patterns of precipitation over the range. In particular, inferred precipitation suggests that gridded products underestimate precipitation for higher-elevation basins whose aspect faces prevailing winds. Better agreement is found in lower-elevation and leeward basins. Collectively, the findings suggest that the development of spatially distributed precipitation datasets should not consider precipitation gauge data in isolation, but should also consider other related hydrologic observations in order to better resolve patterns of precipitation in complex terrain.

Download or read book Issues in Environmental Research and Application 2011 Edition written by and published by ScholarlyEditions. This book was released on 2012-01-09 with total page 3062 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues in Environmental Research and Application: 2011 Edition is a ScholarlyEditions™ eBook that delivers timely, authoritative, and comprehensive information about Environmental Research and Application. The editors have built Issues in Environmental Research and Application: 2011 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about Environmental Research and Application in this eBook to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Issues in Environmental Research and Application: 2011 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.

Download or read book Encyclopedia of Atmospheric Sciences written by Gerald R. North and published by Elsevier. This book was released on 2014-09-14 with total page 2874 pages. Available in PDF, EPUB and Kindle. Book excerpt: Encyclopedia of Atmospheric Sciences, Second Edition, Six Volume Set is an authoritative resource covering all aspects of atmospheric sciences, including both theory and applications. With more than 320 articles and 1,600 figures and photographs, this revised version of the award-winning first edition offers comprehensive coverage of this important field. The six volumes in this set contain broad-ranging articles on topics such as atmospheric chemistry, biogeochemical cycles, boundary layers, clouds, general circulation, global change, mesoscale meteorology, ozone, radar, satellite remote sensing, and weather prediction. The Encyclopedia is an ideal resource for academia, government, and industry in the fields of atmospheric, ocean, and environmental sciences. It is written at a level that allows undergraduate students to understand the material, while providing active researchers with the latest information in the field. Covers all aspects of atmospheric sciences—including both theory and applications Presents more than 320 articles and more than 1,600 figures and photographs Broad-ranging articles include topics such as atmospheric chemistry, biogeochemical cycles, boundary layers, clouds, general circulation, global change, mesoscale meteorology, ozone, radar, satellite remote sensing, and weather prediction An ideal resource for academia, government, and industry in the fields of atmospheric, ocean, and environmental sciences

Download or read book Understanding Hydrological Extremes and their Impact in a Changing Climate Observations Modeling and Attribution written by Xingcai Liu and published by Frontiers Media SA. This book was released on 2021-03-12 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hydrologic Modeling Response to NEXRAD and Raingage Spatial Variability and Strategic Watershed Management written by Pushpa Tuppad and published by . This book was released on 2006 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Applications of Remote Sensing GIS in Water Resources and Flooding Risk Managements written by Hongjie Xie and published by MDPI. This book was released on 2018-08-21 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue "Applications of Remote Sensing/GIS in Water Resources and Flooding Risk Managements" that was published in Water