Статті в журналах: "Estuarine oceanography Mathematical models"

1

Hetland, Robert D., and W. Rockwell Geyer. "An Idealized Study of the Structure of Long, Partially Mixed Estuaries*." Journal of Physical Oceanography 34, no. 12 (December 1, 2004): 2677–91. http://dx.doi.org/10.1175/jpo2646.1.

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Abstract Classic models of estuarine circulation are reexamined using a three-dimensional, primitive equation numerical ocean model. The model is configured using an idealized estuary/shelf domain with rectangular cross section, constant vertical mixing, and steady riverine discharge. Tidal dispersion is neglected, so the analysis does apply to well-mixed estuaries and lagoons. Estuarine scales for the length of steady-state salt intrusion, vertical stratification, and estuarine exchange flow estimated from steady-state model results are found to have the same functional relationships to vertical mixing and riverine discharge as the classic analytic solutions. For example, for steady-state conditions, the stratification is found to be virtually independent of the strength of vertical mixing. The estuarine structure was controlled by the interior estuarine circulation, and not by limited exchange at the mouth. Thus, the numerical solutions were not “overmixed,” although the solutions showed a dependence on freshwater flux functionally similar to the overmixed solution. Estuarine adjustment time scales are also estimated from the simulations, and they are related to the steady-state estuarine scales. Two classes of nonsteady solutions are examined: the response to a step change in riverine discharge and estuarine response to changes in vertical mixing. Spring/neap tidal variations are examined by modulating the (spatially constant) vertical mixing with a fortnightly period. Unlike the steady solutions, there is a clear dependence of stratification on mixing rate in the time-dependent solutions. The simulations involving changes in riverine discharge show asymmetries between response to increasing and decreasing river flow that are attributed to quadratic bottom drag.

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2

Blaise, S., and E. Deleersnijder. "Improving the parameterisation of horizontal density gradient in one-dimensional water column models for estuarine circulation." Ocean Science 4, no. 4 (November 19, 2008): 239–46. http://dx.doi.org/10.5194/os-4-239-2008.

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Abstract. A new parameterisation of horizontal density gradient for a one-dimensional water column estuarine model, inspired by the first-order finite-difference upwind scheme, is presented. This parameterisation prevents stratification from growing indefinitely, a deficiency usually referred to as "runaway stratification". It is seen that, using this upwind-like parameterisation, the salinity must remain comprised between upper and lower bounds set a priori and that any initial over- or under-shooting is progressively eliminated. Simulations of idealised and realistic estuarine regimes indicate that the new parameterisation lead to results that are devoid of the runaway stratification phenomenon, as opposed to previously used models.

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3

Vasconcelos, R. P., O. Le Pape, M. J. Costa, and H. N. Cabral. "Predicting estuarine use patterns of juvenile fish with Generalized Linear Models." Estuarine, Coastal and Shelf Science 120 (March 2013): 64–74. http://dx.doi.org/10.1016/j.ecss.2013.01.018.

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4

Franz, Guilherme Augusto Stefanelo, Paulo Leitão, Aires dos Santos, Manuela Juliano, and Ramiro Neves. "From regional to local scale modelling on the south-eastern Brazilian shelf: case study of Paranaguá estuarine system." Brazilian Journal of Oceanography 64, no. 3 (September 2016): 277–94. http://dx.doi.org/10.1590/s1679-875920161195806403.

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Abstract The applicability of a numerical model following a downscaling methodology was evaluated for the south-eastern Brazilian shelf (regional model) and Paranaguá estuarine system (local model). This approach permits the simulation of different scale processes, such as storm surges and coastal upwelling, and is suitable for operational forecasting purposes. When large areas are covered by regional models, the tidal propagation inside the domain can be significantly affected by the local tidal potential, mainly where the resonance phenomenon is observed. The south-eastern Brazilian shelf is known for the resonance of the third-diurnal principal lunar tidal constituent (M3), the largest amplitudes being found in the Paranaguá estuarine system. Therefore, the significance of the local tidal potential was assessed in this study for the most important tidal constituents inside the estuarine system (including M3). The model validation was performed with tidal gauge data, Argo float profiles and satellite measurements of Sea Surface Temperature. The methodology described in this study can be replicated for other important estuarine systems located on the south-eastern Brazilian shelf. Furthermore, the numerical model was developed within a perspective of operational nowcast/forecast simulations, useful for several activities such as navigation and response to emergencies (e.g., oil spills).

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5

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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6

Swaney, D. P., D. Scavia, R. W. Howarth, and R. M. Marino. "Estuarine classification and response to nitrogen loading: Insights from simple ecological models." Estuarine, Coastal and Shelf Science 77, no. 2 (April 2008): 253–63. http://dx.doi.org/10.1016/j.ecss.2007.09.013.

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7

Blaise, S., and E. Deleersnijder. "A new parameterisation of salinity advection to prevent stratification from running away in a simple estuarine model." Ocean Science Discussions 5, no. 2 (June 2, 2008): 187–211. http://dx.doi.org/10.5194/osd-5-187-2008.

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Abstract. A new parameterisation of horizontal salinity advection for a one-dimensional water-column estuarine model, inspired by the first-order finite-difference upwind scheme, is presented. This parameterisation prevents stratification from growing indefinitely, a numerical artefact usually referred to as "runaway stratification". It is seen that, using this upwind-like parameterisation, the salinity must remain comprised between upper and lower bounds set a priori and that any initial over- or under-shooting is progressively eliminated. Simulations of idealised and realistic estuarine regimes indicate that the new parameterisation lead to results that are devoid of the runaway stratification artefact, as opposed to previously used models.

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8

Bose, S. K., P. Ray, and B. K. Dutta. "Mathematical Models for Mixing and Dispersion in Forecasting and Management of Estuarine Water Quality." Water Science and Technology 19, no. 9 (September 1, 1987): 183–93. http://dx.doi.org/10.2166/wst.1987.0079.

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The dispersion or spread of a dissolved or suspended substance in an estuarine system occurs mainly due to the non-uniformity of velocity distribution, including turbulent fluctuations, shear stress at the boundary and surface stress caused by winds. The mixing and dispersion phenomena in rivers and estuaries are extremely important in water quality management and control. The development of a dispersion model in harmony with the nature of the flow field in a river or estuary is necessary in the estimation and correlation of dispersion parameters, called dispersion coefficients, which may, in general, be anisotropic in a multidimensional transport process. The earlier one-dimensional models have gradually given way to higher dimensional models for better description of the phenomena as well as for more accurate estimation of parameters. Field studies of dispersion of tracers have been the most important method of generating data for parameter estimation. A number of correlations for mixing and dispersion coefficients in terms of flow rates and other fundamental system parameters are available. The present study incorporates the analysis, assessment and applications of various dispersion and mixing models available. Also, a critical appraisal of the validity, inherent degree of uncertainty and the range of applications of different correlations has been incorporated.

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9

Davies, Simon. "Mathematical models for Arctic submarine pipeline protection." Marine Pollution Bulletin 17, no. 3 (March 1986): 85–86. http://dx.doi.org/10.1016/0025-326x(86)90396-6.

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10

Niu, X.-F., H. L. Edmiston, and G. O. Bailey. "Time Series Models for Salinity and Other Environmental Factors in the Apalachicola Estuarine System." Estuarine, Coastal and Shelf Science 46, no. 4 (April 1998): 549–63. http://dx.doi.org/10.1006/ecss.1997.0294.

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11

Lewis, Nathaniel S., Eric W. Fox, and Theodore H. DeWitt. "Estimating the distribution of harvested estuarine bivalves with natural-history-based habitat suitability models." Estuarine, Coastal and Shelf Science 219 (April 2019): 453–72. http://dx.doi.org/10.1016/j.ecss.2019.02.009.

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12

Fram, Jonathan P., Maureen A. Martin, and Mark T. Stacey. "Dispersive Fluxes between the Coastal Ocean and a Semienclosed Estuarine Basin." Journal of Physical Oceanography 37, no. 6 (June 1, 2007): 1645–60. http://dx.doi.org/10.1175/jpo3078.1.

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Abstract Scalar exchange between San Francisco Bay and the coastal ocean is examined using shipboard observations made across the Golden Gate Channel. The study consists of experiments during each of the following three “seasons”: winter/spring runoff (March 2002), summer upwelling (July 2003), and autumn relaxation (October 2002). Within each experiment, transects across the channel were repeated approximately every 12 min for 25 h during both spring and neap tides. Velocity was measured from a boat-mounted ADCP. Scalar concentrations were measured at the surface and from a tow-yoed SeaSciences Acrobat. Net salinity exchange rates for each season are quantified with harmonic analysis. Accuracy of the net fluxes is confirmed by comparison with independently measured values. Harmonic results are then decomposed into flux mechanisms using temporal and spatial correlations. In this study, the temporal correlation of cross-sectionally averaged salinity and velocity (tidal pumping flux) is the largest part of the dispersive flux of salinity into the bay. From the tidal pumping flux portion of the dispersive flux, it is shown that there is less exchange than was found in earlier studies. Furthermore, tidal pumping flux scales strongly with freshwater flow resulting from the density-driven movement of a tidally trapped eddy and stratification-induced increases in ebb–flood frictional phasing. Complex bathymetry makes salinity exchange scale differently with flow than would be expected from simple tidal asymmetry and gravitational circulation models.

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13

Alidi, Abdulaziz S. "Locating oil spill response centres using mathematical models." Marine Pollution Bulletin 26, no. 4 (April 1993): 216–19. http://dx.doi.org/10.1016/0025-326x(93)90625-t.

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14

Frick, Walter E., Tarang Khangaonkar, Anne C. Sigleo, and Zhaoqing Yang. "Estuarine–ocean exchange in a North Pacific estuary: Comparison of steady state and dynamic models." Estuarine, Coastal and Shelf Science 74, no. 1-2 (August 2007): 1–11. http://dx.doi.org/10.1016/j.ecss.2007.02.019.

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15

Morais, Gisele C., Maurício G. Camargo, and Paulo Lana. "Intertidal assemblage variation across a subtropical estuarine gradient: How good conceptual and empirical models are?" Estuarine, Coastal and Shelf Science 170 (March 2016): 91–101. http://dx.doi.org/10.1016/j.ecss.2015.12.020.

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16

James, M. K. "The Timing of Collision Avoidance Manoeuvres: Descriptive Mathematical Models." Journal of Navigation 47, no. 2 (May 1994): 259–72. http://dx.doi.org/10.1017/s0373463300012169.

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This paper examines the frequency distributions of the ranges at which vessels take action to avoid collision. Published data from simulator exercises are employed. Both give-way and stand-on vessels are considered. Lognormal distributions fitted to the data are shown to be superior to those previously published. Underlying ‘causal’ models are developed which are capable of generating the observed distributions.

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17

Chen, Shih-Nan, W. Rockwell Geyer, David K. Ralston, and James A. Lerczak. "Estuarine Exchange Flow Quantified with Isohaline Coordinates: Contrasting Long and Short Estuaries." Journal of Physical Oceanography 42, no. 5 (May 1, 2012): 748–63. http://dx.doi.org/10.1175/jpo-d-11-086.1.

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Abstract Isohaline coordinate analysis is used to compare the exchange flow in two contrasting estuaries, the long (with respect to tidal excursion) Hudson River and the short Merrimack River, using validated numerical models. The isohaline analysis averages fluxes in salinity space rather than in physical space, yielding the isohaline exchange flow that incorporates both subtidal and tidal fluxes and precisely satisfies the Knudsen relation. The isohaline analysis can be consistently applied to both subtidally and tidally dominated estuaries. In the Hudson, the isohaline exchange flow is similar to results from the Eulerian analysis, and the conventional estuarine theory can be used to quantify the salt transport based on scaling with the baroclinic pressure gradient. In the Merrimack, the isohaline exchange flow is much larger than the Eulerian quantity, indicating the dominance of tidal salt flux. The exchange flow does not scale with the baroclinic pressure gradient but rather with tidal volume flux. This tidal exchange is driven by tidal pumping due to the jet–sink flow at the mouth constriction, leading to a linear dependence of exchange flow on tidal volume flux. Finally, a tidal conversion parameter Qin/Qprism, measuring the fraction of tidal inflow Qprism that is converted into net exchange Qin, is proposed to characterize the exchange processes among different systems. It is found that the length scale ratio between tidal excursion and salinity intrusion provides a characteristic to distinguish estuarine regimes.

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18

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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19

Whitney, Michael M., and Richard W. Garvine. "Simulating the Delaware Bay Buoyant Outflow: Comparison with Observations." Journal of Physical Oceanography 36, no. 1 (January 1, 2006): 3–21. http://dx.doi.org/10.1175/jpo2805.1.

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Abstract Coastal buoyant outflows from rivers and estuaries previously have been studied with field research, laboratory experiments, and numerical models. There is a dire need to evaluate model performance in light of coastal current observations. This research simulates the Delaware Bay outflow and compares results with observations of estuarine and shelf conditions. Observations include an estuarine salinity climatology, a record of freshwater delivery to the shelf, coastal current salinity mappings, and surface drifter data. Simulation efforts focus on spring 1993 and spring 1994, the primary field study period. The simulation is forced with river discharge, winds, and tides; only tidal-averaged results are discussed. Estuarine salinity results are consistent with the observed lateral salinity pattern, vertical structure, and response to river discharge. Salinities within the lower bay agree with observations, but the simulation overestimates the along-estuary salinity gradient. Observed and simulated freshwater delivery exhibit the same amplitude of response to river discharge and winds. The simulation produces a buoyant outflow that is generally consistent with the observed buoyancy signature, width, length, and vertical structure over a variety of river discharge and wind conditions. The simulated coastal current, however, tends to be somewhat shorter and fresher than observed. Simulated surface drifter paths exhibit the observed onshore advection during downwelling winds as well as offshore transport and current reversals during upwelling winds. A statistical evaluation based on shelf salinity mappings indicates that the model reproduces the observed variance and has only a small bias (less than 10% of plume buoyancy signature). The rms error of 1.2 psu is linked to the shorter and fresher nature of the simulated coastal current. Observational comparisons discussed in this paper indicate that the model can simulate many coastal current features and its response to river discharge and wind forcing.

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20

Fitzpatrick, James J. "Assessing skill of estuarine and coastal eutrophication models for water quality managers." Journal of Marine Systems 76, no. 1-2 (February 2009): 195–211. http://dx.doi.org/10.1016/j.jmarsys.2008.05.018.

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21

Deleersnijder, Eric, Emmanuel Hanert, Hans Burchard, and Henk A. Dijkstra. "On the mathematical stability of stratified flow models with local turbulence closure schemes." Ocean Dynamics 58, no. 3-4 (September 19, 2008): 237–46. http://dx.doi.org/10.1007/s10236-008-0145-6.

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22

Toledo, Pamela, Audrey M. Darnaude, Edwin J. Niklitschek, Vilma Ojeda, Raphaël Voué, Félix P. Leiva, Maylis Labonne, and Cristian B. Canales-Aguirre. "Partial migration and early size of southern hake Merluccius australis: a journey between estuarine and oceanic habitats off Northwest Patagonia." ICES Journal of Marine Science 76, no. 4 (December 6, 2018): 1094–106. http://dx.doi.org/10.1093/icesjms/fsy170.

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Abstract Partial migration is a key adaptive strategy, increasingly observed across multiple taxa. To investigate partial migration and life-cycle diversity of Merluccius australis in northwestern Patagonia, we analysed isotopic (δ13C, δ18O) and elemental (11B, 23Na, 24 Mg, 55Mn, 86Sr, 138Ba) compositions of otoliths from juveniles, sub-adults, and adults to identify nursery origins, habitats used, and migratory behaviours of multiple cohorts (1990–2005). Influence of early size upon migration was assessed by comparing back-calculated sizes at demersal recruitment between resident and migratory adults. Although partial migration occurred at both estuarine and oceanic nursery habitats, migratory behaviour was more frequent in fish of estuarine origin (59%) than in fish of oceanic origin (17%). Adults of estuarine origin dominated both estuarine (92%) and oceanic (77%) sampling areas. Although we found no significant differences in size at demersal recruitment between oceanic-resident and oceanic-migratory fish, a strong relationship between size at demersal recruitment and migratory behaviour appeared in fish of estuarine origin, whose probability of migration increased from 5% to 95% as demersal recruitment size increased from 18.8 to 23.6 cm. Further research on M. australis life cycle is required to incorporate sub-population processes into the stock assessment and management models being used for this overexploited species.

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23

Fisher, Alexander W., Lawrence P. Sanford, and Malcolm E. Scully. "Wind-Wave Effects on Estuarine Turbulence: A Comparison of Observations and Second-Moment Closure Predictions." Journal of Physical Oceanography 48, no. 4 (April 2018): 905–23. http://dx.doi.org/10.1175/jpo-d-17-0133.1.

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AbstractObservations of turbulent kinetic energy, dissipation, and turbulent stress were collected in the middle reaches of Chesapeake Bay and were used to assess second-moment closure predictions of turbulence generated beneath breaking waves. Dissipation scaling indicates that the turbulent flow structure observed during a 10-day wind event was dominated by a three-layer response that consisted of 1) a wave transport layer, 2) a surface log layer, and 3) a tidal, bottom boundary layer limited by stable stratification. Below the wave transport layer, turbulent mixing was limited by stable stratification. Within the wave transport layer, where dissipation was balanced by a divergence in the vertical turbulent kinetic energy flux, the eddy viscosity was significantly underestimated by second-moment turbulence closure models, suggesting that breaking waves homogenized the mixed surface layer to a greater extent than the simple model of TKE diffusing away from a source at the surface. While the turbulent transport of TKE occurred largely downgradient, the intermittent downward sweeps of momentum generated by breaking waves occurred largely independent of the mean shear. The underprediction of stress in the wave transport layer by second-moment closures was likely due to the inability of the eddy viscosity model to capture the nonlocal turbulent transport of the momentum flux beneath breaking waves. Finally, the authors hypothesize that large-scale coherent turbulent eddies played a significant role in transporting momentum generated near the surface to depth.

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24

Campuzano, Francisco, Flávio Santos, Lucian Simionesei, Ana R. Oliveira, Estrella Olmedo, Antonio Turiel, Rodrigo Fernandes, et al. "Framework for Improving Land Boundary Conditions in Ocean Regional Products." Journal of Marine Science and Engineering 10, no. 7 (June 22, 2022): 852. http://dx.doi.org/10.3390/jmse10070852.

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The coupling of coastal or regional ocean models to hydrological models or observed data is currently an uncommon practice in operational oceanography. Though hydrological models are regarded as a powerful and useful tool for estimating the quantity and quality of freshwater running in a watershed, they fail to provide accurate results for river flow reaching the coastal area due to water-management activities occurring within the river catchment, activities such as human consumption, irrigation, storage, etc. For this reason, many coastal and regional ocean models continue to impose surface zero-salinity discharges as land boundary conditions for representing such a dynamic boundary. Moreover, river flows are based in climatologies, thus neglecting seasonal and interannual variability. To achieve those objectives, this study proposes an integrated methodology ranging from watershed models to validation in the coastal area and passing through methods and proxies for integrating the freshwater flows into regional ocean models. The main objective of this study is to explore the results obtained by using more sophisticated land boundary conditions based on the capacities of state-of-the-art hydrologic models combined with observation networks. In addition to the evaluation of the source of river-flow data, this work also explores the use of estuarine proxies based on simple modelling grids. The estuarine proxies enable the incorporation of the mixing processes that take place in estuaries into the land fluxes and obtain the plume momentum. The watershed, estuarine proxies, and ocean were modelled using the MOHID Water modelling system and evaluated in western Iberia waters. The modelling results served to illustrate the sea surface salinity extension of the Western Iberia Buoyant Plume (WIBP) during an extreme event in March 2018.

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25

Davidson, K., and A. Cunningham. "Accounting for nutrient processing time in mathematical models of phytoplankton growth." Limnology and Oceanography 41, no. 4 (June 1996): 779–83. http://dx.doi.org/10.4319/lo.1996.41.4.0779.

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26

Verri, Giorgia, Nadia Pinardi, Frank Bryan, Yu-heng Tseng, Giovanni Coppini, and Emanuela Clementi. "A box model to represent estuarine dynamics in mesoscale resolution ocean models." Ocean Modelling 148 (April 2020): 101587. http://dx.doi.org/10.1016/j.ocemod.2020.101587.

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27

Revilla, José A., Kalin N. Koev, Rafael Díaz, César Álvarez, and Antonio Roldán. "Methods for studying dissolved oxygen levels in coastal and estuarine waters receiving combined sewer overflows." Water Science and Technology 32, no. 2 (July 1, 1995): 95–103. http://dx.doi.org/10.2166/wst.1995.0081.

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One factor in determining the transport capacity of coastal interceptors in Combined Sewer Systems (CSS) is the reduction of Dissolved Oxygen (DO) in coastal waters originating from the overflows. The study of the evolution of DO in coastal zones is complex. The high computational cost of using mathematical models discriminates against the required probabilistic analysis being undertaken. Alternative methods, based on such mathematical modelling, employed in a limited number of cases, are therefore needed. In this paper two alternative methods are presented for the study of oxygen deficit resulting from overflows of CSS. In the first, statistical analyses focus on the causes of the deficit (the volume discharged). The second concentrates on the effects (the concentrations of oxygen in the sea). Both methods have been applied in a study of the coastal interceptor at Pasajes Estuary (Guipúzcoa, Spain) with similar results.

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Dijkstra, Yoeri M., and Henk M. Schuttelaars. "A Unifying Approach to Subtidal Salt Intrusion Modeling in Tidal Estuaries." Journal of Physical Oceanography 51, no. 1 (January 2021): 147–67. http://dx.doi.org/10.1175/jpo-d-20-0006.1.

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AbstractThe salinity structure in estuaries is classically described in terms of the salinity structure as well mixed, partially mixed, or salt wedge. The existing knowledge about the processes that result in such salinity structures comes from highly idealized models that are restricted to either well-mixed and partially mixed cases or subtidal salt wedge estuaries. Hence, there is still little knowledge about the processes driving transitions between these different salinity structures and the estuarine parameters at which such a transition is found. As an important step toward a unified description of the dominant processes driving well-mixed, partially mixed, and salt wedge estuaries, a subtidal width-averaged model applicable to all these salinity structures is developed and systematically analyzed. Using our model, we identify four salinity regimes, resulting from different balances of dominant processes. It is shown that each regime is uniquely determined by two dimensionless parameters: an estuarine Froude and Rayleigh number, representing freshwater discharge and tidal mixing, respectively, resulting in a classification of the regimes in terms of these two parameters. Furthermore, analytical expressions to approximate the salt intrusion length in each regime are developed. These expressions are used to illustrate that the salt intrusion length in different regimes responds in a highly different manner to changes in depth and freshwater discharge. As one of the key results, we show that there are only very weak relations between the process-based regime of an estuary and the salt intrusion length and top–bottom stratification. This implies that the salinity structure of an estuary cannot be uniquely matched to a regime.

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29

Nogueira, E., F. F. Pérez, and A. F. Rı́os. "Modelling Thermohaline Properties in an Estuarine Upwelling Ecosystem (Rı́a de Vigo: NW Spain) Using Box-Jenkins Transfer Function Models." Estuarine, Coastal and Shelf Science 44, no. 6 (June 1997): 685–702. http://dx.doi.org/10.1006/ecss.1996.0143.

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30

Scully, Malcolm E., W. Rocky Geyer, and John H. Trowbridge. "The Influence of Stratification and Nonlocal Turbulent Production on Estuarine Turbulence: An Assessment of Turbulence Closure with Field Observations." Journal of Physical Oceanography 41, no. 1 (January 1, 2011): 166–85. http://dx.doi.org/10.1175/2010jpo4470.1.

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Abstract Field observations of turbulent kinetic energy (TKE), dissipation rate ɛ, and turbulent length scale demonstrate the impact of both density stratification and nonlocal turbulent production on turbulent momentum flux. The data were collected in a highly stratified salt wedge estuary using the Mobile Array for Sensing Turbulence (MAST). Estimates of the dominant length scale of turbulent motions obtained from the vertical velocity spectra provide field confirmation of the theoretical limitation imposed by either the distance to the boundary or the Ozmidov scale, whichever is smaller. Under boundary-limited conditions, anisotropy generally increases with increasing shear and decreased distance to the boundary. Under Ozmidov-limited conditions, anisotropy increases rapidly when the gradient Richardson number exceeds 0.25. Both boundary-limited and Ozmidov-limited conditions demonstrate significant deviations from a local production–dissipation balance that are largely consistent with simple scaling relationships for the vertical divergence in TKE flux. Both the impact of stratification and deviation from equilibrium turbulence observed in the data are largely consistent with commonly used turbulence closure models that employ “nonequilibrium” stability functions. The data compare most favorably with the nonequilibrium version of the L. H. Kantha and C. A. Clayson stability functions. Not only is this approach more consistent with the observed critical gradient Richardson number of 0.25, but it also accounts for the large deviations from equilibrium turbulence in a manner consistent with the observations.

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31

McCormick, N. J. "Mathematical models for the mean cosine of irradiance and the diffuse attenuation coefficient." Limnology and Oceanography 40, no. 5 (July 1995): 1013–18. http://dx.doi.org/10.4319/lo.1995.40.5.1013.

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32

Poulos, S. E., and M. B. Collins. "Effluent Diffusion and Sediment Dispersion at Microtidal River Mouths, Predicted Using Mathematical Models." Estuarine, Coastal and Shelf Science 38, no. 2 (February 1994): 189–206. http://dx.doi.org/10.1006/ecss.1994.1012.

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33

Spaulding, Malcolm L., and Daniel L. Mendelsohn. "WQMAP: An Integrated Three-Dimensional Hydrodynamic and Water Quality Model System for Estuarine and Coastal Applications." Marine Technology Society Journal 33, no. 3 (January 1, 1999): 38–54. http://dx.doi.org/10.4031/mtsj.33.3.6.

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WQMAP is an integrated system for modeling the circulation and water quality of estuarine and coastal waters. The system includes a suite of integrated environmental models including a boundary conforming grid generation model, a three hydrodynamic model, and a suite of pollutant transport and fate models (single and multiple constituent and WASP5 eutrophication kinetics). All operate on a boundary conforming grid system and are supported by an embedded geographic information system and environmental data management tools. WQMAP is configured for operation on a Pentium personal computer and features a Windows based user interface. The interface employs point and click and pull down menu operation. Color graphics and animations are used to display model predictions. The system is structured to facilitate application to any geographic area.As an illustration of its capability WQMAP was applied to predict the three-dimensional circulation and thermal dynamics for Mt. Hope Bay, RI, located on the eastern side of Narragansett Bay. The area receives fresh water input from the Taunton River and a thermal discharge from a 1600 MW coal and oil fired power plant located at Bray ton Point, along the north shore of the bay. Model predictions were performed for the month of August 1997 and compared to time series at three stations in the vicinity of the power plant discharge. Measurements of currents, temperature, and salinity were made near the surface and the bottom at each of the three stations. Model predictions (currents, temperature, and salinity) were in good agreement with available data using relative error, root mean square error, linear regression analysis, and error coefficient of variation as quantitative evaluation criteria. Model predictions showed that circulation in the bay is generally dominated by the tide, except in the lower reaches of the Taunton River where density induced, two layer flow becomes important. The thermal structure of the bay is dominated by the power plant discharge in the northwestern section of the bay and otherwise by natural atmospheric heating and cooling. Thermal stratification near the power plant is principally dependent on the discharge plume. It is strongest and most wide spread on ebb tide along the central axis of the plume and weaker during flood tide when the plume is confined to the near shore area.

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34

Melnyk, Oleksiy, Oleg Onishchenko, Svitlana Onyshchenko, Andrii Voloshyn, Yevgen Kalinichenko, Olena Rossomakha, Galyna Naleva, and Oleh Rossomakha. "Autonomous Ships Concept and Mathematical Models Application in their Steering Process Control." TransNav, the International Journal on Marine Navigation and Safety of Sea Transportation 16, no. 3 (2022): 553–51. http://dx.doi.org/10.12716/1001.16.03.18.

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35

Avila, Tatiana Ramos, Anderson Abel de Souza Machado, and Adalto Bianchini. "Estimation of zooplankton secondary production in estuarine waters: Comparison between the enzymatic (chitobiase) method and mathematical models using crustaceans." Journal of Experimental Marine Biology and Ecology 416-417 (April 2012): 144–52. http://dx.doi.org/10.1016/j.jembe.2012.02.015.

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36

Gogina, Mayya, Michael L. Zettler, Irene Wåhlström, Helén Andersson, Hagen Radtke, Ivan Kuznetsov, and Brian R. MacKenzie. "A combination of species distribution and ocean-biogeochemical models suggests that climate change overrides eutrophication as the driver of future distributions of a key benthic crustacean in the estuarine ecosystem of the Baltic Sea." ICES Journal of Marine Science 77, no. 6 (August 5, 2020): 2089–105. http://dx.doi.org/10.1093/icesjms/fsaa107.

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Abstract Species in the brackish and estuarine ecosystems will experience multiple changes in hydrographic variables due to ongoing climate change and nutrient loads. Here, we investigate how a glacial relict species (Saduria entomon), having relatively cold, low salinity biogeographic origin, could be affected by the combined scenarios of climate change and eutrophication. It is an important prey for higher trophic-level species such as cod, and a predator of other benthic animals. We constructed habitat distribution models based occurrence and density of this species across the entire Baltic and estimated the relative importance of different driving variables. We then used two regional coupled ocean-biogeochemical models to investigate the combined impacts of two future climate change and nutrient loads scenarios on its spatial distribution in 2070–2100. According to the scenarios, the Baltic Sea will become warmer and fresher. Our results show that expected changes in salinity and temperature outrank those due to two nutrient-load scenarios (Baltic Sea Action Plan and business as usual) in their effect on S. entomon distribution. The results are relatively similar when using different models with the same scenarios, thereby increasing the confidence of projections. Overall, our models predict a net increase (and local declines) of suitable habitat area, total abundance and biomass for this species, which is probably facilitated by strong osmoregulation ability and tolerance to temperature changes. We emphasize the necessity of considering multiple hydrographic variables when estimating climate change impacts on species living in brackish and estuarine systems.

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37

Vasconcelos, R. P., O. Le Pape, M. J. Costa, and H. N. Cabral. "Corrigendum to “Predicting estuarine use patterns of juvenile fish with Generalized Linear Models” [Est. Coast. Shelf Sci. 120 (2013) 64–74]." Estuarine, Coastal and Shelf Science 134 (December 2013): 188. http://dx.doi.org/10.1016/j.ecss.2013.10.003.

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38

McKiver, W. J., G. Sannino, F. Braga, and D. Bellafiore. "Investigation of model capability in capturing vertical hydrodynamic coastal processes: a case study in the north Adriatic Sea." Ocean Science 12, no. 1 (January 15, 2016): 51–69. http://dx.doi.org/10.5194/os-12-51-2016.

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Abstract. In this work we consider a numerical study of hydrodynamics in the coastal zone using two different models, SHYFEM (shallow water hydrodynamic finite element model) and MITgcm (Massachusetts Institute of Technology general circulation model), to assess their capability to capture the main processes. We focus on the north Adriatic Sea during a strong dense water event that occurred at the beginning of 2012. This serves as an interesting test case to examine both the models strengths and weaknesses, while giving an opportunity to understand how these events affect coastal processes, like upwelling and downwelling, and how they interact with estuarine dynamics. Using the models we examine the impact of setup, surface and lateral boundary treatment, resolution and mixing schemes, as well as assessing the importance of nonhydrostatic dynamics in coastal processes. Both models are able to capture the dense water event, though each displays biases in different regions. The models show large differences in the reproduction of surface patterns, identifying the choice of suitable bulk formulas as a central point for the correct simulation of the thermohaline structure of the coastal zone. Moreover, the different approaches in treating lateral freshwater sources affect the vertical coastal stratification. The results indicate the importance of having high horizontal resolution in the coastal zone, specifically in close proximity to river inputs, in order to reproduce the effect of the complex coastal morphology on the hydrodynamics. A lower resolution offshore is acceptable for the reproduction of the dense water event, even if specific vortical structures are missed. Finally, it is found that nonhydrostatic processes are of little importance for the reproduction of dense water formation in the shelf of the north Adriatic Sea.

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39

McKiver, W. J., G. Sannino, F. Braga, and D. Bellafiore. "Investigation of model capability in capturing vertical hydrodynamic coastal processes: a case study in the North Adriatic Sea." Ocean Science Discussions 12, no. 4 (August 3, 2015): 1625–68. http://dx.doi.org/10.5194/osd-12-1625-2015.

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Abstract. In this work we consider a numerical study of hydrodynamics in the coastal zone using two different models, SHYFEM and MITgcm, to assess their capability to capture the main processes. We focus on the North Adriatic Sea during a strong dense water event that occurred at the beginning of 2012. This serves as an interesting test case to examine both the models strengths and weaknesses, while giving an opportunity to understand how these events affect coastal processes, like upwelling and downwelling, and how they interact with estuarine dynamics. Using the models we examine the impact of setup, surface and lateral boundary treatment, resolution and mixing schemes, as well as assessing the importance of nonhydrostatic dynamics in coastal processes. Both models are able to capture the dense water event, though each displays biases in different regions. The models show large differences in the reproduction of surface patterns, identifying the choice of suitable bulk formulas as a central point for the correct simulation of the thermohaline structure of the coastal zone. Moreover, the different approaches in treating lateral freshwater sources affect the vertical coastal stratification. The results indicate the importance of having high horizontal resolution in the coastal zone, specifically in close proximity to river inputs, in order to reproduce the effect of the complex coastal morphology on the hydrodynamics. A lower resolution offshore is acceptable for the reproduction of the dense water event, even if specific vortical structures are missed. Finally, it is found that nonhydrostatic processes are of little importance for the reproduction of dense water formation in the shelf of the North Adriatic Sea.

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40

Al-Rabeh, Ala, Robin Lardner, Nazmi Gunay, Rizwanullah Khan, Mahmood Hossain, R. M. Reynolds, and W. J. Lehr. "On mathematical and empirical models for surface oil spill transport in the Gulf." Marine Pollution Bulletin 27 (January 1993): 71–77. http://dx.doi.org/10.1016/0025-326x(93)90009-9.

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41

Vasechkina, E. F., I. E. Timchenko, and V. D. Yarin. "Prediction of hydrological phenomena using self-organizing mathematical models." Physical Oceanography 8, no. 3 (May 1997): 185–93. http://dx.doi.org/10.1007/bf02523070.

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42

Azevedo Correia de Souza, Joao Marcos, and Brian Powell. "Different approaches to model the nearshore circulation in the south shore of O'ahu, Hawaii." Ocean Science 13, no. 1 (January 20, 2017): 31–46. http://dx.doi.org/10.5194/os-13-31-2017.

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Abstract. The dynamical interaction between currents, bathymetry, waves, and estuarine outflow has significant impacts on the surf zone. We investigate the impacts of two strategies to include the effect of surface gravity waves on an ocean circulation model of the south shore of O'ahu, Hawaii. This area provides an ideal laboratory for the development of nearshore circulation modeling systems for reef-protected coastlines. We use two numerical models for circulation and waves: Regional Ocean Modeling System (ROMS) and Simulating Waves Nearshore (SWAN) model, respectively. The circulation model is nested within larger-scale models that capture the tidal, regional, and wind-forced circulation of the Hawaiian archipelago. Two strategies are explored for circulation modeling: forcing by the output of the wave model and online, two-way coupling of the circulation and wave models. In addition, the circulation model alone provides the reference for the circulation without the effect of the waves. These strategies are applied to two experiments: (1) typical trade-wind conditions that are frequent during summer months, and (2) the arrival of a large winter swell that wraps around the island. The results show the importance of considering the effect of the waves on the circulation and, particularly, the circulation–wave coupled processes. Both approaches show a similar nearshore circulation pattern, with the presence of an offshore current in the middle beaches of Waikiki. Although the pattern of the offshore circulation remains the same, the coupled waves and circulation produce larger significant wave heights ( ≈ 10 %) and the formation of strong alongshore and cross-shore currents ( ≈ 1 m s−1).

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43

Pickens, BA, JC Taylor, MD Campbell, and WB Driggers. "Offshore snapper and shark distributions are predicted by prey and area of nearby estuarine environments in the Gulf of Mexico, USA." Marine Ecology Progress Series 682 (January 20, 2022): 169–89. http://dx.doi.org/10.3354/meps13925.

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Seascape ecology has demonstrated that marine fishes are associated with multiscale habitat characteristics; however, most species distribution models focus on only a few predictors (e.g. depth, temperature), and this limits knowledge of essential fish habitat characteristics. Our objectives were to (1) determine habitat associations of offshore predatory marine fishes using a comprehensive suite of predictors, including area of nearby estuarine environments, (2) assess variable influence, and (3) model the spatial distribution of selected fishes in the families Carcharhinidae and Lutjanidae. We hypothesized that the concept of coastal outwelling would be evidenced by species associations with areas of nearby estuarine environments, and prey abundance would correlate with predator distributions. Species distribution models were developed for 2 snapper and 3 shark species in the northern Gulf of Mexico, USA. We used 34 multiscale predictors to evaluate how fish probability of presence or catch per unit effort (CPUE) were associated with oceanography, geography, substrate, area of nearby wetlands and estuaries, and prey abundance. Boosted regression trees, a machine-learning technique, modeled the most influential variables and predicted distributions. Model validation showed an overall accuracy of 79-86%, and CPUE models explained >40% of model deviance. Oceanographic variables, particularly mixed layer depth, were most influential and most frequently selected. As hypothesized, predatory fish distributions were predicted by prey abundances, and shark distributions were predicted by area of nearby coastal wetlands and estuaries. Our findings suggest that spatial models can provide novel insights into prey associations and linkages of marine species with nearby wetlands and estuaries.

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44

Wirth, A. "Laminar and weakly turbulent oceanic gravity currents performing inertial oscillations." Ocean Science 8, no. 3 (May 3, 2012): 301–17. http://dx.doi.org/10.5194/os-8-301-2012.

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Abstract. The small scale dynamics of a weakly turbulent oceanic gravity current is determined. The gravity current considered is initially at rest and adjusts by performing inertial oscillations to a geostrophic mean flow. The dynamics is explored with a hierarchy of mathematical models. The most involved are the fully 3-D Navier-Stokes equations subject to the Boussinesq approximation. A 1-D and 0-D mathematical model of the same gravity current dynamics are systematically derived. Using this hierarchy and the numerical solutions of the mathematical models, the turbulent dynamics at the bottom and the interface is explored and their interaction investigated. Three different regimes of the small scale dynamics of the gravity current are identified, they are characterised by laminar flow, coherent roll vortices and turbulent dynamics with coherent streaks and bursts. The problem of the rectification of the turbulent fluxes, that is, how to average out the fluctuations and calculate their average influence on the flow, is considered. It is shown that two different regimes of friction are superposed, an Ekman friction applies to the average geostrophic flow and a linear friction, not influenced by rotation, to the inertial oscillations. The combination of the two makes the bulk friction non-local in time for the 0-D model. The implications of the results for parametrisations of the Ekman dynamics and the small scale turbulent fluxes in the planetary boundary layer are discussed.

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45

Wirth, A. "Laminar and weakly turbulent oceanic gravity currents performing inertial oscillations." Ocean Science Discussions 8, no. 5 (September 28, 2011): 2001–45. http://dx.doi.org/10.5194/osd-8-2001-2011.

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Анотація:

Abstract. The small scale dynamics of a weakly turbulent oceanic gravity current is determined. The gravity current considered is initially at rest and adjusts by performing inertial oscillations to a geostrophic mean flow. The dynamics is explored with a hierarchy of mathematical models. The most involved are the fully 3-D Navier-Stokes equations subject to the Boussinesq approximation. A 1-D and 0-D mathematical model of the same gravity current dynamics are systematically derived. Using this hierarchy and the numerical solutions of the mathematical models, the turbulent dynamics at the bottom and the interface is explored and their interaction investigated. Three different regimes of the small scale dynamics of the gravity current are identified, they are characterised by laminar flow, coherent roll vortices and turbulent dynamics with coherent streaks and bursts. The problem of the rectification of the turbulent fluxes, that is how to average out the fluctuations and calculate their average influence on the flow is considered. It is shown that two different regimes of friction are superposed, an Ekman friction applies to the average geostrophic flow and a linear friction, not influenced by rotation, to the inertial oscillations. The combination of the two makes the bulk friction non-local in time for the 0-D model. The implications of the results for parametrisations of the Ekman dynamics and the small scale turbulent fluxes in the planetary boundary layer are discussed.

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46

Félix-Ortiz, José A., E. Alberto Aragón-Noriega, Nicolás Castañeda-Lomas, Guillermo Rodríguez-Domínguez, Wenceslao Valenzuela-Quiñónez, and Sergio Castillo-Vargasmachuca. "Individual growth analysis of the Pacific yellowlegs shrimp Penaeus californiensis via multi-criteria approach." Latin American Journal of Aquatic Research 48, no. 5 (November 1, 2020): 768–78. http://dx.doi.org/10.3856/vol48-issue5-fulltext-2555.

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Length-frequency data of juveniles and sub-adults of Penaeus californiensis were analyzed, collected from January 2002 to January 2003 in the Agiabampo lagoon system and adjacent marine coastal zone. Six models were parameterized with four criteria, in addition to a mixed criterion (fat-tail and depensatory), to estimate the parameters that best fit the growth curve. The model that best fit was the Johnson model with the mixed criterion in females and males: k = 6.02 (5.93-6.12); L∞ = 188.8 (186.3-191.8); t0 = 0.0221 (0.0207-0.0234); and: k = 8.98 (8.85-9.12); L∞ =153.3 (151.7-155.0); t0 = 0.0386 (0.0378-0.0394), respectively. The conclusion is that: 1) the mixture approach found in this study as best leads to the application of a very high-performance objective function to analyze individual length-at-age variability, 2) shows that the best model to describe the growth trajectory of P. californiensis in marine and estuarine environments is a sigmoid curve with an inflection point near to cero age (Johnson model).

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47

Carlton-Wippern, Kitt C. "On Loxodromic Navigation." Journal of Navigation 45, no. 2 (May 1992): 292–97. http://dx.doi.org/10.1017/s0373463300010791.

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This article addresses the mathematical foundations of rhumblines or loxodrome curves. These curves are critical to navigation and small-scale charting by virtue of the fact that they provide an efficient routeing from one point on a surface to another by means of a constant ‘course angle‘. This article will develop the necessary mathematical relations for the construction of such a curve, then apply the relations to both spherical and oblate-spheroidal surfaces. The purpose of this article is to produce a superior oblate-spheroidal loxodrome curve, which better models curves or routes of constant course on the actual, approximately oblatespheroidal, Earth.

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48

Bruno, Daniel Osvaldo, Santiago Aldo Barbini, Juan Martín Díaz de Astarloa, and Patricia Martos. "Fish abundance and distribution patterns related to environmental factors in a choked temperate coastal lagoon (Argentina)." Brazilian Journal of Oceanography 61, no. 1 (March 2013): 43–53. http://dx.doi.org/10.1590/s1679-87592013000100005.

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The aim of this study was to assess the influence of environmental factors on the fish distribution and abundance in Mar Chiquita coastal lagoon. Seasonal fish sampling stations were distributed along the lagoon and grouped in three zones from a mixo-oligohaline waters zone with high contribution of freshwater to a mixo-eurihaline waters zone with high marine water influence. A mixo-mesohaline waters zone characterized the middle part of the lagoon. The results showed that the fish composition was dominated by marine estuarine dependent (ED) species in all three zones and in all seasons: Odontesthes argentinensis, Brevoortia aurea, Mugil liza and Micropogonias furnieri were the most representative species. The following important ecological category was freshwater fishes (FW), with Platanichthys platana and Jenynsia multidentata being the most representative species. According to the best model selected, by fitting generalized linear models, abundance of ED increased as water temperature increased during summer and autumn in all three zones. The highest abundance was recorded in the mixo-eurihaline waters zone. On the other hand, FW abundance increased with high rainfall and also when easterly winds blew. In conclusion, a differential habitat use by the species that occur in the Mar Chiquita coastal lagoon was observed. A few ED species dominated the fish composition but FW species also made use of the lagoon during periods of heavy rainfall.

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49

Bonanno, A., F. Placenti, G. Basilone, R. Mifsud, S. Genovese, B. Patti, M. Di Bitetto, et al. "Variability of water mass properties in the Strait of Sicily in summer period of 1998–2013." Ocean Science Discussions 11, no. 2 (March 13, 2014): 811–37. http://dx.doi.org/10.5194/osd-11-811-2014.

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Abstract. The Strait of Sicily plays a crucial role in determining the water mass exchanges and related properties between western and eastern Mediterranean. The presence of sills to the east and west of the Strait of Sicily and the complex seabed topography modulate the thermohaline circulation of the Mediterranean basin. An anti-estuarine circulation is mainly characterized, from a dynamic point of view, by a two-layer system: a surface layer composed of Atlantic Water (AW) flowing eastward, essentially dominated by mesoscale processes, and a subsurface layer composed of Levantine Intermediate Water (LIW) flowing in the opposite direction; the topography appears to play an important role. Furthermore, there are transition water masses with variable hydrological characteristics. The dataset here studied is a time series 16 years long (1998–2013), which highlights the high horizontal and vertical interannual variability affecting the study area. Strong temperature-salinity correlations, in the intermediate layer, for specific time intervals, could be linked to the reversal of sub-surface circulation in the Central Ionian Sea. Moreover, a long-term monitoring of the hydrographic properties of water masses across this strait allow the modelers to assess the performance of hydrological models of this area.

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50

Toxopeus, Serge L. "Deriving mathematical manoeuvring models for bare ship hulls using viscous flow calculations." Journal of Marine Science and Technology 14, no. 1 (July 23, 2008): 30–38. http://dx.doi.org/10.1007/s00773-008-0002-9.

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