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This book reports the first systematic monitoring and modelling study on water availability, water quality and seawater intrusion of the Shatt al-Arab River (SAR) on the border of Iraq and Iran, where causes and concentration levels of salinity have not yet been fully understood, let alone addressed, leading to conflicting perceptions of its origin (external or internal), the natural conditions and the practices that can explain the current critical conditions. Current scientific knowledge on the SAR salinity problem is deficient, partially due to the complex and dynamic interaction between marine and terrestrial salinity sources, including return flows by water users of the different water sectors in the Euphrates and Tigris rivers upstream of the SAR. The development of a new series of monitoring stations and various modelling approaches helped to better understand the interactions between these different sources. The comprehensive and detailed dataset formed the basis for a validated analytical model that can predict the extent of seawater relative to other salinity sources in an estuary, and for a hydrodynamic model that can predict salinity changes. The adaptability of the models to changing conditions makes them directly applicable by water managers. The procedure can be applied to other comparable systems.
The system of the Tigris-Euphrates Rivers is one of the great river systems of southwestern Asia. It comprises the Tigris and Euphrates Rivers, which follow roughly parallel courses through the heart of the Middle East. The lower portion of the region that they run through is known as Mesopotamia, was one of the cradles of civilisation. There are several environmental factors that govern the nature of the two rivers and shape the landscape the two rivers running through. Geological events create rivers, climate monitor the water supply, the surrounding land influences the vegetation and the physical and chemical features of water. The Tigris-Euphrates system runs through the territory of four countries, Iraq, Iran, Turkey and Syria. Therefore, any scientific approach to the environment of these two rivers should include the natural history events in these countries. The book "Tigris and Euphrates Rivers: Their Environment from Headwaters to Mouth" will be divided into nine parts. These parts deal with the issues of the environment, the status of the flora and fauna, the abiotic aspects, ecology, hydrological regime of the two rivers, the biotic aspects. Water resources, stress of the environment, conservation issues. Since the book of Julian Rzoska "Euphrates and Tigris Mesopotamian Ecology and Destiny" in 1980, no book or major reference has been published that includes between its cover the facts and information that the present book will present. Therefore, the importance of the present book falls in stating the present status of the environment of the two rivers and the comparison of their environment between now and that of 37 years ago as given by J. Rzoska (1980). The recent studies showed that there are a large number of natural and political events that happened within the last three decades in the area of the Tigris-Euphrates river system that for sure have done a great change to the environment of the two rivers and consequently changing the biological and non-biological resources of the two rivers. This book will be a reference book to both Academic and students across the Middle East in different disciplines of knowledge to use in their researches on Tigris-Euphrates river system. The scholars interested in this area will use this book as a guide to compare this freshwater system with other areas in Asia and the world.
This book gathers selected high-quality research papers presented at the Sixth International Congress on Information and Communication Technology, held at Brunel University, London, on February 25–26, 2021. It discusses emerging topics pertaining to information and communication technology (ICT) for managerial applications, e-governance, e-agriculture, e-education and computing technologies, the Internet of things (IoT) and e-mining. Written by respected experts and researchers working on ICT, the book offers a valuable asset for young researchers involved in advanced studies. The book is presented in four volumes.
This book includes the papers presented in International Conference on Advanced Science and Engineering 2019 (ICOASE2019), which held in Duhok, Kurdistan Region-Iraq, on April 2-4, 2019. The conference is organized by both the University of Zakho and Duhok Polytechnic University. The conference, and consequently these proceedings, aimed to give more concrete expression to the natural sciences and engineering applications with a new multilateral scientific forum that emphasizes the vulnerability and proactive remediation from an Earth and Environmental point of view. This book covers a wide range of questions and gives advanced themes on current research focusing on emerging environmental issues and challenges in chemistry, biology, physics, and related areas in geoscience with their applications.
This book answers key questions about environment, people and their shared future in deltas. It develops a systematic and holistic approach for policy-orientated analysis for the future of these regions. It does so by focusing on ecosystem services in the world’s largest, most populous and most iconic delta region, that of the Ganges-Brahmaputra delta in Bangladesh. The book covers the conceptual basis, research approaches and challenges, while also providing a methodology for integration across multiple disciplines, offering a potential prototype for assessments of deltas worldwide. Ecosystem Services for Well-Being in Deltas analyses changing ecosystem services in deltas; the health and well-being of people reliant on them; the continued central role of agriculture and fishing; and the implications of aquaculture in such environments.The analysis is brought together in an integrated and accessible way to examine the future of the Ganges Brahmaputra delta based on a near decade of research by a team of the world’s leading scientists on deltas and their human and environmental dimensions. This book is essential reading for students and academics within the fields of Environmental Geography, Sustainable Development and Environmental Policy focused on solving the world’s most critical challenges of balancing humans with their environments. This book is licensed under a Creative Commons Attribution 4.0 International License.
This dissertation discusses the use of numerical models to simulate the effects of climate variability and change on Chesapeake and Delaware Bays, two large coastal plain estuaries in the Mid-Atlantic Region of the United States that are both home to productive ecosystems, important ports, and large concentrations of human population. Estuaries like these bays are uniquely characterized by salinity variation from riverine freshwater to oceanic saltwater, both horizontally and vertically, and by the strength of their tides. From a meteorological perspective, estuaries are interesting because they are influenced by many aspects ofweather and climate variability, including runoff and winds. Future climate changes, including changesin river discharge and mean sea level, are also likely to produce significant changes in estuarine salinity and circulation and could alter estuarine ecosystems. To predict the effects these changes may haveon estuarine salinity, circulation, and ecosystems, numerical model simulations are often applied.However, the predictive capability of numerical models is unknown due in part to a lack of knowledge about historical trends and whether numerical models can reproduce them. This dissertation is composed of three studies that address this lack of knowledge. The first study of this dissertation analyzes data from tide gauges in Chesapeake and Delaware Bays and compares the results with model simulations to determine what trends are present and whether the numerical model correctly predicts these trends. When using the numerical model for predictions, it is also important to account for uncertainty in the model and its inputs, but doing so is difficult due to the chain of computationally expensive models typically used to simulate estuaries. The second study of this dissertation examines a method to account for uncertainty in future river discharge, and the third study conducts an analysis of which inputs the numerical model is most sensitive to.In the first study, statistical models show negative M2 amplitude trends at the mouths of both bays, while some upstream locations have insignificant or positive trends. To determine whether sea-level rise isresponsible for these trends, a term for mean sea level is included in the statistical models and the results are compared with with predictions from numerical and analytical models. The observed and predicted sensitivities of M2 amplitude and phase to mean sea level are similar, although the numerical model amplitude is less sensitive to sea level. The sensitivity occurs as a result of strengthening and shifting of the amphidromic system in the Chesapeake Bay and decreasing frictional effects and increasing convergence in the Delaware Bay. After accounting for the effect of sea level, significant negative background M2 and S2 amplitude trends are present; these trends may be related to other factors such as dredging, tide gauge errors, or river discharge. Projected changes in tidal amplitudes due to sea-level rise over the twenty-first century are substantial in some areas, but depend significantly on modeling assumptions.The second study examines the impacts of methods for model selection on projections of runoff change for the Susquehanna River Basin. The results from an ensemble of 29 global climate models and 29 corresponding hydrological model simulations were compared with the results that would have been obtained by applying five different selection strategies to the climate model data and using only the selected models to drive the hydrological model. Only one method, the KKZ algorithm, produced results that met the objective of the method and were not strongly sensitive to the number of models selected. Regardless of the selection method used, the results for small model subsets (fewer than about 7 models) were highly variable and failed to cover the uncertainty present in the full model dataset. On the other hand, results from the complete model ensemble may be affected by structurally and statistically similar models. This study shows that the methods and models used in similar top-down studies should be carefully chosen and that the results obtained should be interpreted with caution.Finally, estuarine physics and water quality are strongly controlled by climate and oceanographic variability.Climate and oceanographic conditions are likely to change in the future as a result of global climate change, and it is important to consider how these changes, and how uncertainty surrounding these changes,could affect water quality and management. To do so, numerical models are typically used to simulate estuarine physics and water quality under scenarios of future conditions. However, the numerical models typically used for simulating estuaries are computationally demanding, limiting the ability to understand and quantify uncertainty in the model results. In the third study of this dissertation, a computationally inexpensive statistical model, or metamodel, is tested as a surrogate for numerical model simulations. The metamodel is fit to 12 numerical model simulations of the Chesapeake Bay and used to simulate stratification, circulation, and mean salinity under sampled probability distributions of projected future mean sea level, river discharge, and tidal amplitudes along the shelf. The simulations from the metamodel show that future salinity, stratification, and circulation are all likely to be higher than present-day averages. However, the metamodel indicates that model projections of salinity and stratification are highly sensitive to uncertainty about future tidal amplitudes along the shelf. Since previous studies have focused on potential changes in either river discharge or sea level while neglecting any change in tidal amplitude, these results demonstrate the importance of conducting a thorough sensitivity and uncertainty analysis. Future studies should build from this concept by including more sources of uncertainty, such as wind speed and direction and model parameters and structures.The results in this dissertation show that although numerical models are capable of reproducing some past changes, the impacts of future climate and oceanographic changes on these estuaries remain highly uncertain. Salinity and stratification in the Chesapeake Bay are fairly likely to increase as a result of a highly probable increase in mean sea level, although exact changes are especially sensitive to changes in tidal amplitude. Model simulations of future tides in both bays appear to be sensitive to the methods used to model sea-level rise even though the simulations of past tides in this dissertation are not. In future work, it will be important to consider this uncertainty, to consider other uncertainties that were neglected in this dissertation, and to examine the impacts on biogeochemistry and overall ecosystem health.
This book is geared for advanced level research in the general subject area of remote sensing and modeling as they apply to the coastal marine environment. The various chapters focus on the latest scientific and technical advances in the service of better understanding coastal marine environments for their care, conservation and management. Chapters specifically deal with advances in remote sensing coastal classifications, environmental monitoring, digital ocean technological advances, geophysical methods, geoacoustics, X-band radar, risk assessment models, GIS applications, real-time modeling systems, and spatial modeling. Readers will find this book useful because it summarizes applications of new research methods in one of the world’s most dynamic and complicated environments. Chapters in this book will be of interest to specialists in the coastal marine environment who deals with aspects of environmental monitoring and assessment via remote sensing techniques and numerical modeling.
Modern field-scale numerical models of estuaries have become widely used to study estuarine dynamics and to assess the impacts of engineering projects on estuaries. While current estuarine models focus primarily on the large-scale tidal dynamics, the model developed in the present study applies higher resolution than pre-existing models to capture the multiscale physics in a realistic estuary (the Snohomish River estuary). The scales range from tidally-driven variability in free surface, velocity and salinity in the estuary to the local-scale interaction of the tidal flow with an abrupt sill that has a dimension of roughly 10 m by 100 m. The model is developed using the SUNTANS solver and employs the Eulerian-Lagrangian Method (ELM) for advection of momentum for improved stability in the presence of substantial wetting and drying. The unstructured mesh extends more than 20 km to cover the advection of the salinity front, while the finest resolution applied around the sill is on the order of meters. Model predictions of free surface, currents and salinity are in good agreement with field measurements. Sensitivity analysis shows that the bathymetry of the intertidal mudflats across the bypass is critical for accurate prediction of the circulation around the sill, while bottom drag, advection of momentum, and fresh river inflow has a smaller and limited effect on the tidal flows. The performance of several two-equation turbulence closure models (k-kl, k-epsilon and k-omega) and stability functions (KC and CA) in predicting mixing and stratification is evaluated via the generic length scale (GLS) approach, and it shows small differences between the closure models. The model robustly obtains reasonable temporal and spatial mixing patterns in the estuary at different stages of a tidal cycle. A quadratic interpolation method is implemented for ELM following the framework in Walters et al. (2007), and both an idealized backward-facing step test case and field-scale simulations show improved accuracy and reduced diffusion and dissipation with the quadratic interpolation. When the quadratic interpolation is implemented with a fine mesh that incorporates 1 m resolution around the sill, the model captures the recirculating eddies downstream of the sill observed during ebb tides, and the velocity structures along a cross-channel transect close to the sill compare favorably to measurements. Finally, the highly variable local salinity field resulting from the interaction of the sill with the advection of the salinity front is discussed based on model results.