Journal articles: 'Estuarine hydrodynamics'

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Khojasteh, Danial, Steve Hottinger, Stefan Felder, Giovanni De Cesare, Valentin Heimhuber, David J. Hanslow, and William Glamore. "IMPACT OF SEA LEVEL RISE ON HYDRODYNAMICS OF ESTUARIES WITH RESTRICTED ENTRANCES." Coastal Engineering Proceedings, no. 36v (December 28, 2020): 3. http://dx.doi.org/10.9753/icce.v36v.management.3.

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Worldwide, hundreds of millions of people who live on or near estuarine environments are vulnerable to sea level rise (SLR). Using clustering techniques and moving beyond static models and case studies, this study used a large ensemble of idealised estuary models of varying scale, geometry, level of entrance constriction, and SLR scenarios. It was found that tidal forcing, degree of entrance restriction, and estuarine length can primarily control the tidal dynamics of prismatic estuaries under SLR. Further, restricting an entrance can be presented as a potential solution to offset SLR induced tidal amplification if the associated impacts on entrance stability, navigation, and flooding are considered.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/vOptOAbqN3U

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Tanaka, Hitoshi, and Hubert Chanson. "Estuarine hydrodynamics and morphodynamics: a perspective." Coastal Engineering Journal 60, no. 4 (October 2, 2018): 385–86. http://dx.doi.org/10.1080/21664250.2018.1563323.

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Asp, Nils Edvin, Carlos Augusto França Schettini, Eduardo Siegle, Marcio Sousa da Silva, and Roney Nonato Reis de Brito. "The dynamics of a frictionally-dominated Amazonian estuary." Brazilian Journal of Oceanography 60, no. 3 (September 2012): 391–403. http://dx.doi.org/10.1590/s1679-87592012000300011.

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The hydrodynamics, morphology and sedimentology of the Taperaçu estuary were investigated. This is one of several estuaries located within the largest mangrove fringe in the world, bordering the Amazon region, subject to a macrotidal regime and regionally atypical negligible fresh water supply. The results reveal widespread sand banks that occupy the central portion of the estuarine cross-section. Well-sorted very fine sandy sediments of marine origin prevail. Shorter flood phases, with substantially higher current velocities, were observed in the upper sector of Taperaçu, as expected for a shallow, friction-dominated estuary. However, ebb domination can be expected for estuaries with large associated mangrove areas and substantial estuarine infilling, both of which situations occur on the Taperaçu. The tidal asymmetry favoring flood currents could be the result of the absence of an effective fluvial discharge. Furthermore, it was observed that the Taperaçu is connected by tidal creeks to the neighboring Caeté estuary, allowing a stronger flux during the flood and intensifying the higher flood currents. As a whole, the results have shown a complex interaction of morphological aspects (friction, fluvial drainage, connections with neighbor estuaries, infilling and large storage area) in determining hydrodynamic patterns, thus improving the understanding of Amazon estuaries.

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Ávila, Rafael André, Priscila Mulattieri Suarez Orozco, Mauro Michelena Andrade, and Osmar Olinto Möller. "Temporal Variability of Suspended-Solids Concentration in the Estuarine Channel of Patos Lagoon, Southern Brazil." Water 13, no. 5 (February 28, 2021): 646. http://dx.doi.org/10.3390/w13050646.

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The assessment of suspended-solids dynamics is crucial for the effective monitoring of estuarine environments. As the recurring in-situ sampling is usually problematic, the calibration of the backscattering from acoustic Doppler profilers has shown to be a reliable technique to estimate the suspended-solids concentration (SSC) in estuaries and rivers. In this study, we obtained a linear model that provides SSC estimates for the estuarine channel of Patos Lagoon by calibrating turbidity and acoustic data with in-situ concentration samples. The model output was analyzed in terms of its relationship with estuarine hydrodynamics and temporal variability. In this estuary, the supply of suspended solids is known to be due the runoff from its main tributaries, but also through the exchanges between the estuary and the coastal ocean. Both sources provide sediments and organic solids which affect water quality, geomorphology, and harbor operations. Results show that SSC is strongly linked to estuarine hydrodynamics, where concentrations increase with streamflow. During outflow periods, higher concentrations are associated with river runoff, whereas with inflow conditions they are induced by southern and southwesterly winds. However, relationship between SSC and streamflow is asymmetrical, meaning that the largest concentrations are majorly linked to outflow currents and downstream transport.

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Aiyesimoju, Kolawole O. "Assessing the Effect of Longitudinal Density Gradient on Estuarine Hydrodynamics." Hydrology Research 21, no. 1 (February 1, 1990): 65–80. http://dx.doi.org/10.2166/nh.1990.0005.

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If the impact of longitudinal density gradient on the hydrodynamics of estuaries is negligible, then in water quality simulations, the hydrodynamics can be decoupled from the mass transport which would lead to substantial savings in computational time and storage requirements. It is thus important to be able to assess this impact beforehand. The impact of longitudinal density gradients is evaluated analytically in the context of a one-dimensional wide rectangular channel taking into account the influence of bed slope, bottom friction, type of boundary condition and transient effects. The analysis predicts actual errors that would arise in numerical computations from near exactly in the best cases to within a factor of 6 in the worst cases. It should thus be useful for at least an order of magnitude prediction of the errors that would arise from the neglect of the effect of longitudinal density gradient on estuarine hydrodynamics.

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António, Maria Helena Paulo, Elisa H. Fernandes, and Jose H. Muelbert. "Impact of Jetty Configuration Changes on the Hydrodynamics of the Subtropical Patos Lagoon Estuary, Brazil." Water 12, no. 11 (November 16, 2020): 3197. http://dx.doi.org/10.3390/w12113197.

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Coastal infrastructure alterations, such as jetty expansions, are designed to provide improvements to natural dredging and safety of marine access and to maximize the management and efficiency of ports. Furthermore, these alterations have the potential to cause significant environmental changes to estuaries and adjacent coastal areas. Here, the hydrodynamics of Pathos Lagoon was investigated before and after the jetty alterations, where the jetty was increased by approximately 10–18% and the mouth width was reduced by 15%. The TELEMAC-3D numerical model was calibrated and validated using the field data, and then simulated for characteristic low and high extreme discharge years for the old and new jetty configurations. Results showed a flow reduction of approximately 20% both in the ebb and flood conditions in the new configuration, which was accompanied by a slight change in the propagation angle of the western jetty current. Reduction of the saltwater intrusion was registered during both the high and low discharge conditions with the new jetty configuration. During the high discharge periods with NE winds, saltwater intrusion did not reach the previous estuarine inland boundary. During the period of low discharge with SW wind, salinity did not reach further than 180 km inland. Reduced saltwater intrusion was estimated landwards and in the shallow embayments. The horizontal stratification structure of the salinity changed, with the partial centralization of the flow in the access channel. The observed hydrodynamic changes from the infrastructure modifications could affect the estuarine ecosystem by increasing the sediment retention, reducing the transport of marine organisms and water properties into the estuary. This study contributes not only to the understanding of hydrodynamic changes but also to the potential optimization of estuarine and coastal management strategies.

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Laruelle, Goulven Gildas, Nicolas Goossens, Sandra Arndt, Wei-Jun Cai, and Pierre Regnier. "Air–water CO<sub>2</sub> evasion from US East Coast estuaries." Biogeosciences 14, no. 9 (May 15, 2017): 2441–68. http://dx.doi.org/10.5194/bg-14-2441-2017.

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Abstract. This study presents the first regional-scale assessment of estuarine CO2 evasion along the US East Coast (25–45° N). The focus is on 42 tidal estuaries, which together drain a catchment of 697 000 km2 or 76 % of the total area within this latitudinal band. The approach is based on the Carbon–Generic Estuary Model (C-GEM) that allows the simulation of hydrodynamics, transport, and biogeochemistry for a wide range of estuarine systems using readily available geometric parameters and global databases of seasonal climatic, hydraulic, and riverine biogeochemical information. Our simulations, performed using conditions representative of the year 2000, suggest that, together, US East Coast estuaries emit 1.9 Tg C yr−1 in the form of CO2, which corresponds to about 40 % of the carbon inputs from rivers, marshes, and mangroves. Carbon removal within estuaries results from a combination of physical (outgassing of supersaturated riverine waters) and biogeochemical processes (net heterotrophy and nitrification). The CO2 evasion and its underlying drivers show important variations across individual systems, but reveal a clear latitudinal pattern characterized by a decrease in the relative importance of physical over biogeochemical processes along a north–south gradient. Finally, the results reveal that the ratio of estuarine surface area to the river discharge, S∕Q (which has a scale of per meter discharged water per year), could be used as a predictor of the estuarine carbon processing in future regional- and global-scale assessments.

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White, Eric D., Ehab Meselhe, Denise Reed, Alisha Renfro, Natalie Peyronnin Snider, and Yushi Wang. "Mitigating the Effects of Sea-Level Rise on Estuaries of the Mississippi Delta Plain Using River Diversions." Water 11, no. 10 (September 28, 2019): 2028. http://dx.doi.org/10.3390/w11102028.

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Using the Mississippi River as a tool for restoration has been a key element of restoration planning in Louisiana for decades. The results of allowing river water and sediment back into the coastal system are manifested in a number of places in present day Louisiana, with additional plans for large scale sediment and water diversions from the Mississippi River. Many previous numerical modeling studies have focused on sediment delivery to Louisiana estuaries. This study examines the effects of river diversions on salinity gradients in receiving estuarine basins. The Integrated Compartment Model, a planning-level model that simulates multi-decadal change in estuarine hydrodynamics and wetland systems under assumed sea-level rise scenarios, was used to assess the estuarine salinity gradient under potential management regimes. The simulations for current conditions are compared to a future 50-year simulation with additional diversions, as well as cases with a variety of diversion options. This modeling analysis shows that without additional action, 50-years of sea-level rise could result in substantial increases in salinity throughout the Mississippi Delta Plain estuaries. This can be largely offset with additional large river diversions which can maintain variable salinity gradients throughout the estuary basins.

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Hsu, Ming‐Hsi, Albert Y. Kuo, Jan‐Tai Kuo, and Wen‐Cheng Liu. "Modeling estuarine hydrodynamics and salinity for wetland restoration." Journal of Environmental Science and Health, Part A 33, no. 5 (July 1998): 891–921. http://dx.doi.org/10.1080/10934529809376768.

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Oliveira, Anabela, André B. Fortunato, Marta Rodrigues, Alberto Azevedo, João Rogeiro, Samuel Bernardo, Laura Lavaud, et al. "Forecasting contrasting coastal and estuarine hydrodynamics with OPENCoastS." Environmental Modelling & Software 143 (September 2021): 105132. http://dx.doi.org/10.1016/j.envsoft.2021.105132.

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Li, Xin, and De An Wu. "Study on the Yangtze River Estuarine Turbidity Maximum." Applied Mechanics and Materials 90-93 (September 2011): 2774–77. http://dx.doi.org/10.4028/www.scientific.net/amm.90-93.2774.

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This paper presents the definition of the estuarine turbidity maximum, its formation reasons and the factors of variety. According to this information, the Yangtze River estuarine turbidity maximum is analyzed as the typical estuarine turbidity maximum. The results show that North Channel turbidity maximum is different with the others for different hydrodynamics. The Delft3D model is applied to simulation the phenomena and the results are agreed with the analysis.

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Biguino, Beatriz, Fátima Sousa, and Ana C. Brito. "Variability of Currents and Water Column Structure in a Temperate Estuarine System (Sado Estuary, Portugal)." Water 13, no. 2 (January 14, 2021): 187. http://dx.doi.org/10.3390/w13020187.

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The circulation in estuaries promotes the transport of organisms, nutrients, oxygen and sediments. Simultaneously, the mixture of fresh and salt water leads to variations of the physicochemical and biological components of the region. Therefore, it is important to further understand the hydrodynamic patterns of an estuary as one of the bases to understand the whole dynamic of these systems, ecologically important regions that must be preserved. However, little is known about the hydrodynamics of some estuarine systems. In order to bridge the knowledge gap about the Sado estuary, sampling was conducted with the purpose of evaluating some circulation patterns of the estuary and classifying it according to the stratification of the water column. The campaigns were conducted to collect monthly data on the intensity and direction of the currents, and on the temperature and salinity of the water column, between September 2018 and September 2019. The data indicated that water circulation in the Sado estuary, occurred through the two main navigation channels (North and South), according to the tidal regime. Both the temperature and the salinity were homogeneous along the water column, revealing little stratification. The analysis suggests possible hydrodynamic changes of the estuary in the past years.

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Dias, João Miguel, Francisco Pereira, Ana Picado, Carina Lurdes Lopes, João Pedro Pinheiro, Sérgio Miguel Lopes, and Paulo Gabriel Pinho. "A Comprehensive Estuarine Hydrodynamics-Salinity Study: Impact of Morphologic Changes on Ria de Aveiro (Atlantic Coast of Portugal)." Journal of Marine Science and Engineering 9, no. 2 (February 22, 2021): 234. http://dx.doi.org/10.3390/jmse9020234.

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Shallow coastal lagoons driven by tidal processes are extremely dynamic environments prone to continuous natural and anthropogenic pressures. The hydrodynamics of these systems deeply depends on the effect of local morphology on the tidal propagation, so their permanent evolution constantly changes tidal dependent processes. For this reason, the present work aims to review the main characteristics of Ria de Aveiro hydrodynamics, a shallow lagoon located at the Atlantic Coast of Portugal, evaluating its evolution over the last 30 years (between 1987 and 2020) and investigating the main morphological changes in its origin. For this purpose, a comparative analysis is performed to determine the main process, including the observed hydrodynamic changes: Deepening of the inlet channel or of the main lagoon channels. To achieve these goals, the authors explored a remarkable database including bathymetric, tide gauge, and salinity data from 1987 until the present. This analysis is completed by the exploitation of a hydrodynamical model (Delft3D), validated against field data. Several simulations were performed to analyse changes in tidal propagation along the lagoon channels (considering the main semi-diurnal constituent M2), tidal asymmetry, tidal currents, tidal prism, and salinity patterns. The results show that the general deepening of the lagoon observed between 1987 and 2020 led to important changes in the lagoon hydrodynamics, namely the increase/decrease of the M2 constituent amplitude/phase, as well as the increase of tidal currents and salt intrusion within the entire lagoon, with the changes being amplified towards the head of the main channels. Although the inlet deepening partially contributed to the modifications found, the results revealed that the deepening of the main lagoon channels had the most significant contribution to the changes observed during the last 30 years.

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Etemad-Shahidi, A., A. Dorostkar, and Wen-Cheng Liu. "Prediction of salinity intrusion in Danshuei estuarine system." Hydrology Research 39, no. 5-6 (October 1, 2008): 497–505. http://dx.doi.org/10.2166/nh.2008.107.

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The main parameters that affect the flow conditions and intrusion of salt water in an estuary system are tides and the seasonal variation of water discharge. A laterally averaged two-dimensional numerical model called MIKE 11 XZ is used to simulate the hydrodynamics and salinity intrusion of Danshuei River estuarine system. This model can simulate hydrodynamics and water quality in estuaries, reservoirs and lakes. MIKE 11 XZ solves the Reynolds-averaged Navier–Stokes equations by using Abbott–Ionescu finite difference scheme in a non-dimensional vertical σ-coordinate. Vertical eddy diffusivity in the model can be determined by a constant value, a mixing length theory and a k or k−ɛ turbulence closure scheme with Richardson number correction. A series of comprehensive field data obtained from Danshuei estuarine system is used for evaluation, calibration and verification of the model. The friction coefficient was calibrated and verified using water surface elevation and velocity measurements, respectively. Then the vertical eddy diffusivity was calibrated and verified through comparison of salinity measurements in different layers of several stations. Reasonable agreement was obtained between the model results and the observed data using k−ɛ turbulence closure scheme. The model application was investigated with different discharges and the effect of discharge variation on salinity intrusion was determined. The results showed that the fresh water discharge is the main parameter that affects the salinity intrusion in this system. Finally, simple power equations are suggested to predict the salinity intrusion due to the fresh water discharge in different tributaries of the system.

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Volta, C., S. Arndt, H. H. G. Savenije, G. G. Laruelle, and P. Regnier. "C-GEM (v 1.0): a new, cost-efficient biogeochemical model for estuaries and its application to a funnel-shaped system." Geoscientific Model Development Discussions 6, no. 4 (November 14, 2013): 5645–709. http://dx.doi.org/10.5194/gmdd-6-5645-2013.

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Abstract. The first part of this paper describes C-GEM (Carbon – Generic Estuary Model), a new, one-dimensional, generic reactive-transport model for the biogeochemical dynamics of carbon and associated bio-elements (N, P, Si) in estuaries. C-GEM is computationally efficient and reduces data-requirements by using an idealized representation of the estuarine geometry to quantitatively predict the dominant features of the estuarine hydrodynamics, salt transport and biogeochemistry. A protocol for the set-up of C-GEM for an estuarine system is also described. The second part of this paper presents, as a proof of concept, the application of C-GEM to the funnel-shaped Scheldt estuary (Belgium, the Netherlands), one of the best-surveyed system in the world. Steady-state and transient simulations are performed and the performance of C-GEM is evaluated through model-data and model-model comparison, using integrated measures of the estuarine biogeochemical functioning, such as system-wide estimates of the Net Ecosystem Metabolism (NEM). A sensitivity analysis is also carried out to identify model parameters that exert the most important control on biogeochemical processes and to assess the sensitivity of the NEM to uncertainties in parameter values. The paper ends by a short discussion of current model limitations with respect to local, regional and global scale applications.

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Volta, C., S. Arndt, H. H. G. Savenije, G. G. Laruelle, and P. Regnier. "C-GEM (v 1.0): a new, cost-efficient biogeochemical model for estuaries and its application to a funnel-shaped system." Geoscientific Model Development 7, no. 4 (July 4, 2014): 1271–95. http://dx.doi.org/10.5194/gmd-7-1271-2014.

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Abstract. Reactive transport models (RTMs) are powerful tools for disentangling the complex process interplay that drives estuarine biogeochemical dynamics, for assessing the quantitative role of estuaries in global biogeochemical cycles and for predicting their response to anthropogenic disturbances (land-use change, climate change and water management). Nevertheless, the application of RTMs for a regional or global estimation of estuarine biogeochemical transformations and fluxes is generally compromised by their high computational and data demands. Here, we describe C-GEM (Carbon-Generic Estuary Model), a new one-dimensional, computationally efficient RTM that reduces data requirements by using a generic, theoretical framework based on the direct relationship between estuarine geometry and hydrodynamics. Despite its efficiency, it provides an accurate description of estuarine hydrodynamics, salt transport and biogeochemistry on the appropriate spatio–temporal scales. We provide a detailed description of the model, as well as a protocol for its set-up. The new model is then applied to the funnel-shaped Scheldt estuary (BE/NL), one of the best-surveyed estuarine systems in the world. Its performance is evaluated through comprehensive model–data and model–model comparisons. Model results show that C-GEM captures the dominant features of the biogeochemical cycling in the Scheldt estuary. Longitudinal steady-state profiles of oxygen, ammonium, nitrate and silica are generally in good agreement with measured data. In addition, simulated, system-wide integrated reaction rates of the main pelagic biogeochemical processes are comparable with those obtained using a high-resolved, two-dimensional RTM. A comparison of fully transient simulations results with those of a two-dimensional model shows that the estuarine net ecosystem metabolism (NEM) only differs by about 10%, while system-wide estimates of individual biogeochemical processes never diverge by more than 40%. A sensitivity analysis is carried out to assess the sensitivity of biogeochemical processes to uncertainties in parameter values. Results reveal that the geometric parameters LC (estuarine convergence length) and H (water depth), as well as the rate constant of organic matter degradation (kox) exert an important influence on the biogeochemical functioning of the estuary. The sensitivity results also show that, currently, the most important hurdle towards regional- or global-scale applications arises from the lack of an objective framework for sediment and biogeochemical process parameterization. They, therefore, emphasize the need for a global compilation of biogeochemical parameter values that can help identify common trends and possible relationships between parameters and controlling factors, such as climate, catchment characteristics and anthropic pressure.

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Sanchez, Marcos, Rodrigo Carballo, Victor Ramos, Miguel Álvarez, Angela Vazquez, and Gregorio Iglesias. "IMPACT OF TIDAL STREAM ENERGY EXPLOITATION ON ESTUARINE HYDRODYNAMICS." Coastal Engineering Proceedings 1, no. 34 (October 30, 2014): 22. http://dx.doi.org/10.9753/icce.v34.management.22.

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Siegle, Eduardo, Carlos A. F. Schettini, Antonio H. F. Klein, and Elírio E. Toldo Jr. "Hydrodynamics and suspended sediment transport in the Camboriú estuary - Brazil: pre jetty conditions." Brazilian Journal of Oceanography 57, no. 2 (June 2009): 123–35. http://dx.doi.org/10.1590/s1679-87592009000200005.

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Estuarine hydrodynamics is a key factor in the definition of the filtering capacity of an estuary and results from the interaction of the processes that control the inlet morphodynamics and those that are acting in the mixing of the water in the estuary. The hydrodynamics and suspended sediment transport in the Camboriú estuary were assessed by two field campaigns conducted in 1998 that covered both neap and spring tide conditions. The period measured represents the estuarine hydrodynamics and sediment transport prior to the construction of the jetty in 2003 and provides important background information for the Camboriú estuary. Each field campaign covered two complete tidal cycles with hourly measurements of currents, salinity, suspended sediment concentration and water level. Results show that the Camboriú estuary is partially mixed with the vertical structure varying as a function of the tidal range and tidal phase. The dynamic estuarine structure can be balanced between the stabilizing effects generated by the vertical density gradient, which produces buoyancy and stratification flows, and the turbulent effects generated by the vertical velocity gradient that generates vertical mixing. The main sediment source for the water column are the bottom sediments, periodically resuspended by the tidal currents. The advective salt and suspended sediment transport was different between neap and spring tides, being more complex at spring tide. The river discharge term was important under both tidal conditions. The tidal correlation term was also important, being dominant in the suspended sediment transport during the spring tide. The gravitational circulation and Stokes drift played a secondary role in the estuarine transport processes.

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F-Pedrera Balsells, Marta, Manel Grifoll, Manuel Espino, Pablo Cerralbo, and Agustín Sánchez-Arcilla. "Wind-Driven Hydrodynamics in the Shallow, Micro-Tidal Estuary at the Fangar Bay (Ebro Delta, NW Mediterranean Sea)." Applied Sciences 10, no. 19 (October 4, 2020): 6952. http://dx.doi.org/10.3390/app10196952.

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This article investigates water circulation in small-scale (~10 km2), shallow (less than 4 m) and micro-tidal estuaries. The research characterizes the hydrodynamic wind response in these domains using field data from Fangar Bay (Ebro Delta) jointly with three-dimensional numerical experiments in an idealized domain. During calm periods, field data in Fangar Bay show complex water circulation in the inner part of the estuary owing to its shallow depths and positive estuarine circulation in the mouth. Numerical experiments are conducted to investigate wind-induced water circulation due to laterally varying bathymetry. For intense up-bay wind conditions (wind intensities greater than 9 m·s−1), an axially symmetric transverse structure occurs with outflow in the central channel axis and inflow in the lateral shallow areas. These numerical results explain the water circulation observed in Fangar Bay during strong wind episodes, highlighting the role of the bathymetry in a small-scale environment. During these episodes, the water column tends to homogenize rapidly in Fangar Bay, breaking the stratification and disrupting estuarine circulation, consistent with other observations in similar domains.

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Vaz, Nuno, Marcos Mateus, Lígia Pinto, Ramiro Neves, and João Miguel Dias. "The Tagus Estuary as a Numerical Modeling Test Bed: A Review." Geosciences 10, no. 1 (December 20, 2019): 4. http://dx.doi.org/10.3390/geosciences10010004.

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The Tagus Estuary is the largest estuarine system in the Iberian Peninsula. Located in a heavily populated metropolitan area (Lisbon), the estuary-coastal continuum is subject to significant natural variability (e.g., tidal variations, winds, river inflow, etc.) and human pressures (e.g., sewage outflow, infrastructures, coastal reclamation, dredging, etc.). Since the 1980s, the estuary has been a natural laboratory for a great number of multidisciplinary studies, but also a numerical laboratory to test models and to develop new ideas and numerical methodologies. Hydrodynamic and biogeochemical models have been used ever since to ascertain the main spatial and temporal features of the Tagus system, connecting its dynamic to its biogeochemical cycles, providing numerical tools used to increase knowledge and to manage the estuary and nearby coastal waters. The main objective of this paper is to present a synopsis of the scientific output related to numerical studies in the Tagus system, by reviewing more than fifty papers published over the past four decades. Our work provides a historical background and description of the numerical models implemented to address estuarine hydrodynamics, nutrient uptake, primary production, light availability, seasonal and annual cycles and the link between physical, biological and chemical estuarine oceanography.

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Zapata, Carlos, Araceli Puente, Andrés García, Javier García-Alba, and Jorge Espinoza. "The Use of Hydrodynamic Models in the Determination of the Chart Datum Shape in a Tropical Estuary." Water 11, no. 5 (April 29, 2019): 902. http://dx.doi.org/10.3390/w11050902.

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Estuaries are transitional environments with ideal conditions for port construction and navigation. They represent a challenge to hydrographic services due to the dynamics of the seabed and the tidal wave deformation. The bottom slope, the convergence of the channels, and the nonlinear effects produced by the bottom friction produce variation in both the tidal range and the location of the chart datum (CD). In this study, sea level data series obtained from the nodes of the mesh of a hydrodynamic model (virtual tide gauges) were used to calculate the harmonic constituents, form factor, asymmetry, and estuary type. The final chart datum surface, obtained from the hydrodynamic model, was used to determine the separation values between zones and also the number of tidal zones in an estuarine system. It was found that in a complex hydrodynamics scenario, the use of the ellipsoidal referenced surveying (ERS) method is more convenient than traditional tidal zoning survey. In the ERS method, once the CD model is complete, it must be attached to the ellipsoid directly. Finally, the variation of the CD in different scenarios (due to anthropogenic action) was assessed.

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Cai, Huayang, Ping Zhang, Erwan Garel, Pascal Matte, Shuai Hu, Feng Liu, and Qingshu Yang. "A novel approach for the assessment of morphological evolution based on observed water levels in tide-dominated estuaries." Hydrology and Earth System Sciences 24, no. 4 (April 16, 2020): 1871–89. http://dx.doi.org/10.5194/hess-24-1871-2020.

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Abstract. Assessing the impacts of both natural (e.g. tidal forcing from the ocean) and human-induced changes (e.g. dredging for navigation and land reclamation) on estuarine morphology is particularly important for the protection and management of the estuarine environment. In this study, a novel analytical approach is proposed for the assessment of estuarine morphological evolution in terms of tidally averaged depth on the basis of the observed water levels along the estuary. The key lies in deriving a relationship between wave celerity and tidal damping or amplification. For given observed water levels at two gauging stations, it is possible to have a first estimation of both wave celerity (distance divided by tidal travelling time) and tidal damping or amplification rate (tidal range difference divided by distance), which can then be used to predict the morphological changes via an inverse analytical model for tidal hydrodynamics. The proposed method is applied to the Lingdingyang Bay of the Pearl River Estuary, located on the southern coast of China, to analyse the historical development of the tidal hydrodynamics and morphological evolution. The analytical results show surprisingly good correspondence with observed water depth and volume in this system. The merit of the proposed method is that it provides a simple approach for understanding the decadal evolution of the estuarine morphology through the use of observed water levels, which are usually available and can be easily measured.

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Fernandes, Élia, Catarina Teixeira, and Adriano Bordalo. "Coupling between Hydrodynamics and Chlorophyll a and Bacteria in a Temperate Estuary: A Box Model Approach." Water 11, no. 3 (March 21, 2019): 588. http://dx.doi.org/10.3390/w11030588.

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The spatial patterns of chlorophyll a and bacteria were assessed in a temperate Atlantic tidal estuary during seasonal surveys, as well as in consecutive summer spring and neap tides. A box model approach was used to better understand spatial and temporal dynamics of these key estuarine descriptors. The Lima estuary (NW Portugal) was divided into boxes controlled by salinity and freshwater discharge and balance equations were derived for each variable, enabling the calculation of horizontal and vertical fluxes of plankton and, therefore, production or consumption rates. Chlorophyll a tended to burst within the oligohaline zone, whereas higher counts of bacteria were found in the mesohaline stretch. Whenever the water column was stratified, similar tide-independent trends were found for chlorophyll a and bacterial fluxes, with net growth in the upper less saline boxes, and consumption beneath the halocline. In the non-stratified upper estuary, other controls emerged for chlorophyll a and bacteria, such as nitrogen and carbon inputs, respectively. The presented results show that, while tidal hydrodynamics influenced plankton variability, production/consumption rates resulted from the interaction of additional factors, namely estuarine geomorphological characteristics and nutrient inputs. In complex estuarine systems, the rather simple box model approach remains a useful tool in the task of understanding the coupling between hydrodynamics and the behavior of plankton, emerging as a contribution toward the management of estuarine systems.

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Hsu, Ming-Hsi, Albert Y. Kuo, Jan-Tai Kuo, and Wen-Cheng Liu. "Procedure to Calibrate and Verify Numerical Models of Estuarine Hydrodynamics." Journal of Hydraulic Engineering 125, no. 2 (February 1999): 166–82. http://dx.doi.org/10.1061/(asce)0733-9429(1999)125:2(166).

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Shawler, Justin L., Christopher J. Hein, Elizabeth A. Canuel, James M. Kaste, Gregory G. Fitzsimons, Ioannis Y. Georgiou, and Debra A. Willard. "Tidal erosion and upstream sediment trapping modulate records of land-use change in a formerly glaciated New England estuary." Anthropocene Coasts 2, no. 1 (January 1, 2019): 340–61. http://dx.doi.org/10.1139/anc-2018-0034.

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Land clearing, river impoundments, and other human modifications to the upland landscape and within estuarine systems can drive coastal change at local to regional scales. However, as compared with mid-latitude coasts, the impacts of human modifications along sediment-starved formerly glaciated coastal landscapes are relatively understudied. To address this gap, we present a late-Holocene record of changing sediment accumulation rates and sediment sources from sediment cores collected across a tidal flat in the Merrimack River estuary (Mass., USA). We pair sedimentology, geochronology, bulk- and stable-isotope organic geochemistry, and hydrodynamic simulations with historical data to evaluate human and natural impacts on coastal sediment fluxes. During the 17th to 19th centuries, accumulation rates increased by an order of magnitude in the central tidal flat, likely in response to enhanced delivery of terrestrial sediment resulting from upland deforestation. However, the overall increase in accumulation (0.56–2.6 mm/year) within the estuary is subtle and spatially variable across the tidal flats because of coincident anthropogenic land clearing and dam building, upland sediment storage, and estuarine hydrodynamics. This study provides insight into the response of formerly glaciated fluvial-coastal systems to human modifications, and underscores the role of estuarine environmental conditions in modifying upland signals of land-use change.

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LUO, JUN, and SANGUTHEVAR RAJASEKARAN. "PARALLIZING 1-DIMENSIONAL ESTUARINE MODEL." International Journal of Foundations of Computer Science 15, no. 06 (December 2004): 809–21. http://dx.doi.org/10.1142/s0129054104002765.

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Wave simulation is an important problem in engineering. Wave simulation models play significant roles in environmental protection. Wave simulations have thus far been done mostly serially. In order to meet the demand for increased spatial and temporal resolution and uncertainty analysis in environmental models for ecological assessments and water resource managements, it is essential to develop high-performance hydrodynamics and water quality models using parallel techniques. In this paper, algorithms for parallelizing 1-D wave simulation models are proposed. In particular, we introduce a paradigm called Less Talk for reducing communication costs in parallel computing. Our wave models have been implemented using Parallel Virtual Machine (PVM) and Multithreading. The experiments show that these algorithms that employ Less Talk are efficient and the parallel wave simulation models have excellent speedup performances.

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Ouellet, Patrick, and Julian J. Dodson. "Tidal Exchange of Anadromous Rainbow Smelt (Osmerus mordax) Larvae Between a Shallow Spawning Tributary and the St, Lawrence Estuary." Canadian Journal of Fisheries and Aquatic Sciences 42, no. 8 (August 1, 1985): 1352–58. http://dx.doi.org/10.1139/f85-170.

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The factors involved in the riverine transport and tidal exchange of yolk-sac rainbow smelt (Osmerus mordax) larvae between Ouelle River and the St. Lawrence estuary were documented. A 72-h sampling series provided evidence of synchronous nighttime hatching of larvae independent of water temperature and river hydrodynamics. Although light conditions influence the vertical distribution of yolk-sac larvae at the river's mouth, the influence of current speed on larval vertical distribution appears to be a more important element in the dynamics of riverine drift and tidal exchange. Yolk-sac larvae sink to the bottom as water currents decrease prior to low slack water. With the intrusion of estuarine water along the bottom during the flood, yolk-sac larvae drifting from the river appear to be mixed with larger post yolk-sac larvae of estuarine origin resulting in temporary retention at the mouth of Ouelle River. However, longer ebb phases in the river result in a net transport of smelt larvae towards the St. Lawrence estuary. We conclude that the riverine transport and mixing of yolk-sac larvae with the estuarine water mass is controlled principally by the hydrodynamics of the system and the nighttime hatching and specific gravity of yolk-sac larvae.

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Wang, Zheng, Ying Liu, Cui Hong Qin, and Wei Zhang. "Study on Characteristics of Hydrodynamic and Pollutant Transport of the Tributary Estuary in the Three Gorges Reservoir Area." Applied Mechanics and Materials 675-677 (October 2014): 912–17. http://dx.doi.org/10.4028/www.scientific.net/amm.675-677.912.

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To further clarify the impact of construction of the Three Gorges Reservoir on its tributaries. In this study, a three-dimensional hydrodynamic model of Changshou-Fuling section of Yangtze River was developed based on EFDC. Then an analysis of the hydrodynamics and the long term mass transport behaviors under backwater effect in the Taohuaxi River and Longxi River was presented. The results show that mainstream backwater effect plays a significant role in tributary during low-water period. And distinct circulation was shown in tributary estuary. However, in high-water period, estuarine circulation area in Longxi River decreased and disappeared, while the one in Taohuaxi River is still evident. Different input action from mainstreams to tributaries has been discovered.

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Noernberg, Mauricio Almeida, Byanka Damian Mizerkowski, Nicole Gabriele Paloschi, and Joaquim Pereira Bento. "HYDRODYNAMICS AND BIO-OPTICAL ASSESSMENT OF TWO PRISTINE SUBTROPICAL ESTUARIES IN SOUTHERN BRAZIL." Brazilian Journal of Oceanography 62, no. 4 (December 2014): 265–78. http://dx.doi.org/10.1590/s1679-87592014069006204.

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Measuring small-scale physical processes and how they affect the spatial patterns of sea water's optical constituents plays a key role in understanding the functioning of complex coastal ecosystems such as estuaries. The spatial variations of physical and bio-optical water properties were investigated during one spring tidal cycle in austral summer, on two transects across the channel of the Medeiros and Itaqui sub-estuaries. These sub-estuaries are a biosphere reserve, and part of the Paranaguá Estuarine System, located on the Southern Brazilian coast. Both sub-estuaries were classified as Type 1a, wellmixed with low stratification. The salinity variations are in phase with the water level, and the tidal propagation is well represented by a standing wave. The vertical velocity profiles showed little vertical shear, and the intensity of the u-component of the velocity varied semi-diurnally. The upper estuary salt transport was dominated by tidal diffusion in an unstable water column. The optical environment presented a mixed dominance of optically active substances, as indicated by the absorption coefficients of dissolved and particulate matter. The colored dissolved organic matter (CDOM) showed overall conservative behavior and was dominant in light absorption below 550 nm in the Medeiros, while nonalgal particles play the most important role in light absorption in the Itaqui in the blue absorption band. The phytoplanktonic contribution is prominent in the red domain and increases as a function of saline intrusion. However, due to the influence of freshwater discharge and the re-suspension of bottom sediments induced by physical processes, the concentrations of the optical components in the water column do not generally have any simple relationships between them.

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Zorndt, Anna C., Torsten Schlurmann, and Iris Grabemann. "THE INFLUENCE OF EXTREME EVENTS ON HYDRODYNAMICS AND SALINITIES IN THE WESER ESTUARY IN THE CONTEXT OF CLIMATE IMPACT RESEARCH." Coastal Engineering Proceedings 1, no. 33 (December 15, 2012): 50. http://dx.doi.org/10.9753/icce.v33.currents.50.

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The salinity and its longitudinal distribution in the Weser estuary, Germany, has implications for water management as the estuarine water is needed, e.g., for irrigation of the agricultural used hinterlands and as industrial water and because of its intrusion into groundwater. Generally, the salinity distribution is determined by tidal dynamics, river runoff from the catchment area, amount of intruding seawater from the German Bight (North Sea) as well as by the salinities of both river and seawater. Anthropogenic climate change may have an impact on the estuarine dynamics and, thus, on the salinity distribution. This study focuses on the impact of storm surges. A semi-implicit Eulerian-Lagrangian finite element model was used to simulate hydrodynamics and salinities in the estuary. By comparing simulated and observed data of two past storm surges it is shown that the model is well capable of reproducing estuarine dynamics. Possible future changes due to climate change are investigated for three scenario- based storm surges; two of them represent future storm conditions and one specifies reference (today's) conditions for comparison. These storm surges were simulated using boundary conditions from water level simulations with a hydrodynamic model for the North Sea together with the respective meteorological forcing. It can be shown that during storm tides, isohalines penetrate more than 30 km further upstream than during normal conditions. For the most severe scenario-based storm surge, this leads to a salinity increase of up to 30 psu within the mixing zone during the highest storm tide.

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Uchiyama, Yusuke. "Hydrodynamics and Associated Morphological Variations on an Estuarine Intertidal Sand Flat." Journal of Coastal Research 234 (July 2007): 1015–27. http://dx.doi.org/10.2112/04-0336.1.

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Santos, Luísa, Ana L. Santos, Francisco J. R. C. Coelho, Newton C. Marcial Gomes, João Miguel Dias, Ângela Cunha, and Adelaide Almeida. "Relation between bacterial activity in the surface microlayer and estuarine hydrodynamics." FEMS Microbiology Ecology 77, no. 3 (July 19, 2011): 636–46. http://dx.doi.org/10.1111/j.1574-6941.2011.01147.x.

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Yang, Zhaoqing, Tarang Khangaonkar, Maria Calvi, and Kurt Nelson. "Simulation of cumulative effects of nearshore restoration projects on estuarine hydrodynamics." Ecological Modelling 221, no. 7 (April 2010): 969–77. http://dx.doi.org/10.1016/j.ecolmodel.2008.12.006.

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Martín Miguez, Belén, L. Fariña-Busto, F. G. Figueiras, and F. F. Pérez. "Succession of phytoplankton assemblages in relation to estuarine hydrodynamics in the Ría de Vigo: a box-model approach." Scientia Marina 65, S1 (July 30, 2001): 65–76. http://dx.doi.org/10.3989/scimar.2001.65s165.

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Kumbier, Kristian, Rafael C. Carvalho, Athanasios T. Vafeidis, and Colin D. Woodroffe. "Comparing static and dynamic flood models in estuarine environments: a case study from south-east Australia." Marine and Freshwater Research 70, no. 6 (2019): 781. http://dx.doi.org/10.1071/mf18239.

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Static and dynamic flood models differ substantially in their complexity and their ability to represent environmental processes such as storm tide or riverine flooding. This study analysed spatial differences in flood extent between static (bathtub) and dynamic flood models (Delft3D) in estuarine environments with different morphology and hydrodynamics in order to investigate which approach is most suitable to map flooding due to storm surges and river discharge in estuarine environments. Time series of observed water levels and river discharge measurements were used to force model boundaries. Observational data, such as tidal gauge and water level logger measurements, satellite imagery and aerial photography, were used to validate modelling results. Flood extents were calculated including and excluding river discharge to quantify and investigate its effect on the mapping of flooding. Modelling results indicate that the mature estuarine system, which has largely infilled broad flood plains, requires a consideration of bottom friction and riverine discharge through dynamic modelling techniques, whereas static models may provide an alternative approach to map flooding at low cost and low computational expense in young lake-like estuarine systems that have not been infilled with sediments. Our results suggest that estuarine classifications based on geomorphological characteristics can potentially guide flood risk assessments in estuarine environments.

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Bennett, William G., Thomas J. van Veelen, Tom P. Fairchild, John N. Griffin, and Harshinie Karunarathna. "Computational Modelling of the Impacts of Saltmarsh Management Interventions on Hydrodynamics of a Small Macro-Tidal Estuary." Journal of Marine Science and Engineering 8, no. 5 (May 23, 2020): 373. http://dx.doi.org/10.3390/jmse8050373.

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Saltmarshes are considered as natural coastal defences. However, owing to the large context dependency, there is much discussion over their effectiveness in providing coastal protection and the necessity of additional coastal defence interventions. The macro-tidal Taf Estuary in south-west Wales was chosen as the case study in this paper to investigate the effects of anthropogenic coastal defence interventions such as construction of hard defences, managed realignment, and altering land use of the saltmarshes on the complex hydrodynamics of the estuary. A coupled flow–wave–vegetation model, developed using the Delft3D coastal modelling software, was used. The wave and current attenuation role of saltmarshes during two contrasting storm conditions was modelled, with and without saltmarsh management interventions. The study reveals that certain saltmarsh management interventions can have widespread impacts on the hydrodynamics of the estuary. Altering the land use by allowing extensive grazing of saltmarsh by livestock was found to have the largest impact on wave attenuation, where wave heights on the marsh almost doubled when compared with the no-intervention scenario. On the other hand, managed realignment has a significant impact on tidal currents, where tidal currents reached 0.5 m/s at certain locations. Changes in estuarine hydrodynamics can lead to undesired impacts on flooding and erosion, which stresses the importance of understanding the effects of localized anthropogenic coastal management interventions on the entire estuarine system.

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Huggett, Rebecca D., Duncan A. Purdie, and Ivan D. Haigh. "Modelling the Influence of Riverine Inputs on the Circulation and Flushing Times of Small Shallow Estuaries." Estuaries and Coasts 44, no. 1 (July 1, 2020): 54–69. http://dx.doi.org/10.1007/s12237-020-00776-3.

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AbstractSimple flushing time calculations for estuarine systems can be used as proxies for eutrophication susceptibility. However, more complex methods are required to better understand entire systems. Understanding of the hydrodynamics driving circulation and flushing times in small, eutrophic, temperate estuaries is less advanced than larger counterparts due to lack of data and difficulties in accurately modelling small-scale systems. This paper uses the microtidal Christchurch Harbour estuary in Southern UK as a case study to elucidate the physical controls on eutrophication susceptibility in small shallow basins. A depth-averaged hydrodynamic model has been configured of the estuary to investigate the physical processes driving circulation with particular emphasis on understanding the impact of riverine inputs to this system. Results indicate circulation control changes from tidally to fluvially driven as riverine inputs increase. Flushing times, calculated using a particle tracking method, indicate that the system can take as long as 132 h to flush when river flow is low, or as short as 12 h when riverine input is exceptionally high. When total river flow into the estuary is less than 30 m3 s−1, tidal flux is the dominant hydrodynamic control, which results in high flushing times during neap tides. Conversely, when riverine input is greater than 30 m3 s−1, the dominant hydrodynamic control is fluvial flux, and flushing times during spring tides are longer than at neaps. The methodology presented here shows that modelling at small spatial scales is possible but highlights the importance of particle tracking methods to determine flushing time variability across a system.

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Degtyarev, Vladimir Vladimirovich, and Dmitriy Igorevich Ershov. "Numerical modeling of sedimentation of terrigenous material in estuarine areas of rivers." Vestnik MGSU, no. 6 (June 2015): 64–72. http://dx.doi.org/10.22227/1997-0935.2015.6.64-72.

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This article considers some aspects and common problems associated with the organization of parallel calculations in the problems of hydrodynamics. As an example the authors consider the calculation problem of the velocity field in the area of river and sea water mixing and the simulation of sedimentation of terrigenous material.

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Clunies, Gregory J., Ryan P. Mulligan, David J. Mallinson, and J. P. Walsh. "Modeling hydrodynamics of large lagoons: Insights from the Albemarle-Pamlico Estuarine System." Estuarine, Coastal and Shelf Science 189 (April 2017): 90–103. http://dx.doi.org/10.1016/j.ecss.2017.03.012.

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Liu, Wen-Cheng, Ming-Hsi Hsu, Albert Y. Kuo, and Ming-Hsu Li. "INFLUENCE OF BATHYMETRIC CHANGES ON HYDRODYNAMICS AND SALT INTRUSION IN ESTUARINE SYSTEM." Journal of the American Water Resources Association 37, no. 5 (October 2001): 1405–16. http://dx.doi.org/10.1111/j.1752-1688.2001.tb03648.x.

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Chang, Jongwi, and Guan-hong Lee. "Anthropocene Effects of Dredging and Estuarine Dam on Hydrodynamics and Estuarine Turbidity Maximum at an Idealized Estuary: Numerical Study." Journal of the Korean Society for Marine Environment & Energy 21, no. 4 (November 25, 2018): 387–97. http://dx.doi.org/10.7846/jkosmee.2018.21.4.387.

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GARONCE, FLÁVIA A. A., and VALÉRIA S. QUARESMA. "Hydrodynamic Aspects at Vitória Bay Mouth, ES." Anais da Academia Brasileira de Ciências 86, no. 2 (June 2014): 555–70. http://dx.doi.org/10.1590/0001-37652014114012.

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Understading the hydrodynamic behavior and suspended particulated matter (SPM) transport are of great importance in port regions such as Vitória Harbor, which is located at Vitória Bay, Vitória – ES, Brazil. Vitória Bay is an estuary that has not been systematically assessed through a temporal analysis in order to identify its hydrodynamics characteristics and SPM exchange. This study aims to investigate salt and suspended particulate matter flux at the estuarine mouth of Vitória Bay by understanding the temporal variation of salinity, temperature and tidal currents within the water column and at the channel crosssection. Results showed that the estuarine mouth tended to present partial stratification periods during neap tides and little stratification in spring tides. The circulation pattern was mainly influenced by the tide, with little influence from river discharge. With regard to the SPM, the mouth of the estuary tended to show low concentrations, with the highest values occurring during the dry season. A close relationship between momentary discharge, SPM and salt fluxes was observed. Despite all the data was collected at the mouth of the estuary, the system showed an importation trend of salt in all cycles and SPM importation for three of the four studied tidal cycles. Thus, Vitoria Bay is not exporting SPM to the adjacent inner shelf.

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Liu, Wen-Cheng, Min-Hsin Ke, and Hong-Ming Liu. "Response of Salt Transport and Residence Time to Geomorphologic Changes in an Estuarine System." Water 12, no. 4 (April 12, 2020): 1091. http://dx.doi.org/10.3390/w12041091.

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Anthropogenic changes in tidal estuaries have significantly altered bathymetry and topography over the past half century. The geomorphic-driven changes in estuarine hydrodynamics and salt transport remain unclear. To explore this issue, a SELFE (Semi-implicit Eulaerian-Lagrangian Finite Element) -based model was developed and utilized in a case study in the Danshui River, Taiwan. The model was calibrated and validated using observed water level, current, and salinity data from 2015, 2016, and 2017. The performance of the SELFE model corresponded well to the measured data. Furthermore, the validated model was utilized to analyze the hydrodynamics, residual current, limit of salt intrusion, and residence time under the predevelopment (1981) and present (2015) conditions. The predicted results revealed that the time lag of water surface elevation at both high tide and low tide under the present condition was approximately 0.5–2 h shorter under the predevelopment condition. The residual circulation under the predevelopment condition was stronger than under the present condition for low flow, causing the limit of salt intrusion to extend further upstream under the predevelopment condition compared to the limit of salt intrusion under the present condition. The calculated residence time under the predevelopment condition was longer than the residence time under the present condition. The freshwater discharge input is a dominating factor affecting the salt intrusion and residence time in a tidal estuary. A regression correlation between the maximum distance of salt intrusion and freshwater discharge and a correlation between residence time and freshwater discharge were established to predict the limit of salt intrusion and residence time under the predevelopment and present conditions with different scenarios of freshwater discharge input.

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Shan, Shiliang, and Jinyu Sheng. "Examination of circulation, flushing time and dispersion in Halifax Harbour of Nova Scotia." Water Quality Research Journal 47, no. 3-4 (August 1, 2012): 353–74. http://dx.doi.org/10.2166/wqrjc.2012.041.

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This study examines the circulation, flushing time and hydrodynamic connectivity in Halifax Harbour based on three-dimensional currents produced by a multi-nested coastal ocean circulation modelling system. The time-mean currents produced by the modelling system feature two-layer estuarine circulation with a seaward flow in the upper layer and a landward flow in the lower layer in the Harbour. The hydrodynamics in the Harbour are also affected significantly by tides and wind forcing. Based on numerical passive tracer experiments, the estimated e-folding flushing time is about 40 and 90 days in the upper and the entire Bedford Basin, respectively. By comparison, the flushing time is about 2–5 days over the Inner and Outer Harbour, and only about 1 day in the Narrows. Analysis of passive particle trajectories carried by the model currents demonstrates that movements of particles in the Harbour are strongly affected by tidal and storm-induced currents. Hydrodynamic connectivity in the study region is also quantified in terms of a connectivity matrix calculated from particle trajectories.

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Kuang, Cuiping, Kuo Chen, Jie Wang, Yunlong Wu, Xu Liu, and Zilong Xia. "Responses of Hydrodynamics and Saline Water Intrusion to Typhoon Fongwong in the North Branch of the Yangtze River Estuary." Applied Sciences 11, no. 19 (September 27, 2021): 8986. http://dx.doi.org/10.3390/app11198986.

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The typhoon impact on an estuarine environment is complex and systematic. A three-dimensional hydrodynamic and salinity transport model with a high-resolution, unstructured mesh and a spatially varying bottom roughness, is applied to investigate the effects of a historical typhoon, Fongwong, which affected Shanghai, on the hydrodynamics and saline water intrusion in the North Branch (NB) of the Yangtze River Estuary (YRE). The model is well validated through observation data of the tidal level, current velocity and direction, and salinity. The numerical results of this typhoon event show that: (1) the tidal level and its range increase toward the upstream part of the NB due to the combined effects of the funnel-shaped plane geometry of the NB and the typhoon; (2) the current velocity and the flow spilt ratio of the NB varies with the tides, with a maximum increase by 0.13 m/s and 26.61% during the flood tide and a maximum decrease by 0.12 m/s and 83.33% during the ebb tide, i.e., the typhoon enhances the flood current and weakens the ebb current; (3) the salinity value increases in the NB to a maximum of 1.40 psu and water is well-mixed in the vertical direction in the typhoon’s stable and falling period. The salinity distribution gradually recovered to the normal salt wedge pattern in 3 days following the typhoon. Although this study is based on a site-specific model, the findings will provide valuable insights into saline water intrusion under typhoon events, and thus assist in implementing more efficient estuarine management strategies for drinking water safety.

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Liu, Wen-Cheng, Ming-Hsi Hsu, and Albert Y. Kuo. "Modelling of hydrodynamics and cohesive sediment transport in Tanshui River estuarine system, Taiwan." Marine Pollution Bulletin 44, no. 10 (October 2002): 1076–88. http://dx.doi.org/10.1016/s0025-326x(02)00160-1.

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Schulte Ostermann, Tilla, Michael Kleyer, Maike Heuner, Elmar Fuchs, Stijn Temmerman, Ken Schoutens, J. Tjeerd Bouma, and Vanessa Minden. "Hydrodynamics affect plant traits in estuarine ecotones with impact on carbon sequestration potentials." Estuarine, Coastal and Shelf Science 259 (September 2021): 107464. http://dx.doi.org/10.1016/j.ecss.2021.107464.

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McManus, John. "Hydrodynamics of estuaries edited by Bjorn Kjerfve, vol II estuarine case studies, CRC press, 1988. No. of pages: 125." Earth Surface Processes and Landforms 15, no. 4 (June 1990): 384–85. http://dx.doi.org/10.1002/esp.3290150411.

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Amoudry, Laurent, and Alejandro Souza. "INFLUENCE OF TURBULENCE CLOSURE ON ESTUARINE SEDIMENT DYNAMICS AND MORPHODYNAMICS." Coastal Engineering Proceedings 1, no. 32 (January 29, 2011): 78. http://dx.doi.org/10.9753/icce.v32.sediment.78.

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Turbulence significantly impacts hydrodynamics, mixing and sediment dynamics in coastal environments. We employ a three-dimensional model, the Proudman Oceanographic Laboratory Coastal Ocean Modeling System (POLCOMS), to investigate the effects of implementing various turbulence closure schemes on sediment dynamics and morphodynamics. This model is applied to an idealized estuary, which is represented by a straight rectangular basin. A simple tidal flow is forced at one end and a constant river flow is imposed at the other. Most of the turbulence closure schemes employed are implemented via coupling to the General Ocean Turbulence Model (GOTM). Their effects are also compared to the impact of different erosion parameterizations on the numerical results and observed for different sediment properties.

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D'Aquino, Carla de Abreu, Jurandir Pereira Filho, and Carlos Augusto França Schettini. "Fluvial modulation of hydrodynamics and salt transport in a highly stratified estuary." Brazilian Journal of Oceanography 58, no. 2 (June 2010): 165–75. http://dx.doi.org/10.1590/s1679-87592010000200007.

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An oceanographic campaign was conducted in the Araranguá river estuary during the period from May 11th to 13th of 2006 in order to produce a first hydrographic characterization of this system. The campaign was carried out during the spring tide period, and coincidentally after an intense rain event in the region which produced a peak in river discharge. Water level, currents and salinity time series were recorded hourly during a 50-hour period, at a site nearly 7 km upstream from the estuarine mouth. Two longitudinal distributions of salinity along the estuary were also recorded. The hydrographic data time-series were used to compute the advective salt flux in order to investigate the changes in the transport terms as a function of the change in discharge. The results showed that the estuarine structure was strongly modulated by the river discharge. The drop in water level of about 0.5 m during the first 24 hours was directly related to the ebb phase of the river flood. The water column was highly stratified throughout the period, therefore the stratification increased during the last 24 hours. The currents were stronger, ebbing and uni-directional at the beginning and became weaker and bidirectional as the water level went down, assuming a tidal pattern. The total salt transport in the first 25 hours was of -13.6 kg.m-1.s-1 (seawards), decreasing to 3 Kg.m-1.s-1 during the last 25 hours (landwards). It was also noticeable that the pH in the estuary, recorded together with the salinity, was around 5, showing that the water quality in the estuary is affected by the coal mining activity in the hydrographic basin.

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Journal articles on the topic 'Estuarine hydrodynamics'

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