Effects of different vegetation drag parameterizations on the tidal propagation in coastal marshlands

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).

Download Full-text

Analytical Solution for Tidal Propagation in a Leaky Aquifer Extending Finite Distance under the Sea

Journal of Hydraulic Engineering ◽

10.1061/(asce)0733-9429(2008)134:4(447) ◽

2008 ◽

Vol 134 (4) ◽

pp. 447-454 ◽

Cited By ~ 17

Author(s):

Mo-Hsuing Chuang ◽

Hund-Der Yeh

Keyword(s):

Analytical Solution ◽

Tidal Propagation ◽

Finite Distance ◽

Leaky Aquifer

Download Full-text

THE USE OF ARRAY PROCESSORS FOR NUMERICAL MODELLING OF TIDAL ESTUARY DYNAMICS

Coastal Engineering Proceedings ◽

10.9753/icce.v17.142 ◽

1980 ◽

Vol 1 (17) ◽

pp. 142

Author(s):

D. Prandle ◽

E.R. Funke ◽

N.L. Crookshank ◽

R. Renner

Keyword(s):

Numerical Model ◽

Numerical Modelling ◽

Hybrid Model ◽

Numerical Models ◽

Computer Time ◽

Scale Model ◽

Hybrid Modelling ◽

Tidal Propagation ◽

Physical Scale ◽

Array Processors

The use of array processors for the numerical modelling of estuarine systems is discussed here in the context of "hybrid modelling", however, it is shown that array processors may be used to advantage in independent numerical simulations. Hybrid modelling of tidal estuaries was first introduced by fiolz (1977) and later by Funke and Crookshank (1978). In a hybrid model, tidal propagation in an estuary is simulated by dynamically linking an hydraulic (or physical) scale model of part of the estuary to a numerical model of the remaining part in a manner such that a free interchange of flow occurs at the interface(s). Typically, the elevation of the water surface at the boundary of the scale model is measured and transmitted to the numerical model. In return, the flow computed at the boundary of the numerical model is fed directly into the scale model. This approach enables the extent of the scale model to be limited to the area of immediate interest (or to that area where flow conditions are such that they can be most accurately simulated by a scale model). In addition, since the region simulated by the numerical model can be extended almost indefinitely, the problems of spurious reflections from downstream boundaries can be eliminated. In normal use, numerical models are evaluated on the basis of computing requirements, cost and accuracy. The computer time required to simulate one tide cycle is, in itself, seldom of interest except in so far as it affects the above criteria. However in hybrid modelling this parameter is often paramount since concurrent operation of the numerical and scale models requires that the former must keep pace with the latter. The earlier hybrid model of the St. Lawrence (Funke and Crookshank, 1978) involved a one-dimensional numerical model of the upstream regions of the river. However, future applications are likely to involve extensive two-dimensional numerical simulation.

Download Full-text

HYDRODYNAMIC MODELLING OF THE SOUTHERN NORTH SEA

Coastal Engineering Proceedings ◽

10.9753/icce.v16.65 ◽

1978 ◽

Vol 1 (16) ◽

pp. 65

Author(s):

David Prandle

Keyword(s):

North Sea ◽

Three Dimensional ◽

Flood Routing ◽

Hydrodynamic Modelling ◽

One Dimensional ◽

Southern North Sea ◽

Tidal Propagation ◽

Modelling Studies ◽

Residual Flows ◽

Shallow Seas

Numerical modelling of rivers, estuaries and shallow seas has attracted increasing interest over the last two decades. The models have developed from one dimensional (ID) applications to tidal propagation and flood routing through two and, finally, three dimensional applications to motions ranging from "pseudo-turbulence" to annual mean residual flows. The present account describes the development, over the last five years, of the modelling studies carried out by the author concerning the hydrodynamics of the southern North Sea and River Thames. The objective is to identify those major points which have emerged that may have a wider significance.

Download Full-text

MAYA COASTAL PRODUCTION, EXCHANGE, LIFE STYLE, AND POPULATION MOBILITY: A VIEW FROM THE PORT OF XCAMBO, YUCATAN, MEXICO

Ancient Mesoamerica ◽

10.1017/s0956536114000133 ◽

2014 ◽

Vol 25 (1) ◽

pp. 221-238 ◽

Cited By ~ 10

Author(s):

Thelma Sierra Sosa ◽

Andrea Cucina ◽

T. Douglas Price ◽

James H. Burton ◽

Vera Tiesler

Keyword(s):

Geographic Mobility ◽

New Order ◽

Data Sets ◽

Population Mobility ◽

Chemical Research ◽

Economic Production ◽

New Information ◽

Trade Dynamics ◽

Maya Collapse ◽

Coastal Marshlands

AbstractAnchored in archaeological, bioarchaeological, and chemical research conducted at the coastal enclave of Xcambo, this paper examines Classic period Maya coastal saline economic production and exchange, along with the lifestyle, ethnicity, and mobility of the traders. Nestled in the coastal marshlands of the northern Yucatan, Mexico, Xcambo functioned as a salt production center and port during its occupation, maintaining long-reaching ties with other parts of the Maya world and Veracruz. Considered together, the different data sets document a reorientation in Xcambo's exchange routes and connections, which are echoed by increasingly diverse cultural affiliations and an increasing geographic mobility of Xcambo's merchants. This new information confirms the known pattern of gradually intensifying, though still relatively independent, trade dynamics along the Maya coast in the centuries leading up to the so-called “Maya collapse” and the rise of a new merchant league under the control of Chichen Itza. It was this new order that probably led to the swift end of Xcambo soon aftera.d.700.

Download Full-text

Tidal propagation in an oceanic island with sloping beaches

Hydrology and Earth System Sciences ◽

10.5194/hess-14-1341-2010 ◽

2010 ◽

Vol 14 (7) ◽

pp. 1341-1351 ◽

Cited By ~ 5

Author(s):

Y.-C. Chang ◽

D.-S. Jeng ◽

H.-D. Yeh

Keyword(s):

Analytical Solution ◽

Water Table ◽

Finite Length ◽

Oceanic Islands ◽

Higher Order ◽

Oceanic Island ◽

Tidal Propagation ◽

Amplitude Parameter ◽

Present Solution ◽

Order Components

Abstract. In this study, a new analytical solution for describing the tide-induced groundwater fluctuations in oceanic islands with finite length and different slopes of the beaches is developed. Unlike previous solutions, the present solution is not only applicable for a semi-infinite coastal aquifer, but also for an oceanic island with finite length and different sloping beaches. The solution can be used to investigate the effect of higher-order components and beach slopes on the water table fluctuations. The results demonstrate the effect of higher-order components increases with the shallow water parameter or amplitude parameter and the water table level increases as beach slopes decrease.

Download Full-text

Flooding in the Mekong Delta: the impact of dyke systems on downstream hydrodynamics

Hydrology and Earth System Sciences ◽

10.5194/hess-24-189-2020 ◽

2020 ◽

Vol 24 (1) ◽

pp. 189-212 ◽

Cited By ~ 2

Author(s):

Vo Quoc Thanh ◽

Dano Roelvink ◽

Mick van der Wegen ◽

Johan Reyns ◽

Herman Kernkamp ◽

...

Keyword(s):

Mekong Delta ◽

High Flow ◽

Water Levels ◽

Mekong River ◽

Low Flow ◽

Water Level Fluctuations ◽

Tidal Propagation ◽

Extreme Flood ◽

Year 2000 ◽

The Impact

Abstract. Building high dykes is a common measure of coping with floods and plays an important role in agricultural management in the Vietnamese Mekong Delta. However, the construction of high dykes causes considerable changes in hydrodynamics of the Mekong River. This paper aims to assess the impact of the high-dyke system on water level fluctuations and tidal propagation in the Mekong River branches. We developed a coupled 1-D to 2-D unstructured grid using Delft3D Flexible Mesh software. The model domain covered the Mekong Delta extending to the East (South China Sea) and West (Gulf of Thailand) seas, while the scenarios included the presence of high dykes in the Long Xuyen Quadrangle (LXQ), the Plain of Reeds (PoR) and the Trans-Bassac regions. The model was calibrated for the year 2000 high-flow season. Results show that the inclusion of high dykes changes the percentages of seaward outflow through the different Mekong branches and slightly redistributes flow over the low-flow and high-flow seasons. The LXQ and PoR high dykes result in an increase in the daily mean water levels and a decrease in the tidal amplitudes in their adjacent river branches. Moreover, the different high-dyke systems not only have an influence on the hydrodynamics in their own branch, but also influence other branches due to the Vam Nao connecting channel. These conclusions also hold for the extreme flood scenarios of 1981 and 1991 that had larger peak flows but smaller flood volumes. Peak flood water levels in the Mekong Delta in 1981 and 1991 are comparable to the 2000 flood as peak floods decrease and elongate due to upstream flooding in Cambodia. Future studies will focus on sediment pathways and distribution as well as climate change impact assessment.

Download Full-text

Some transient aspects of tidal propagation

Journal of Geophysical Research Atmospheres ◽

10.1029/90ja02181 ◽

1991 ◽

Vol 96 (A2) ◽

pp. 1215-1224 ◽

Cited By ~ 34

Author(s):

François Vial ◽

Jeffrey M. Forbes ◽

Saburo Miyahara

Keyword(s):

Tidal Propagation

Download Full-text

Extension of MF radar tidal measurements to E-region heights (95-125 km): Saskatoon (52°N, 107°W), Canada

Annales Geophysicae ◽

10.1007/s00585-994-0333-8 ◽

1994 ◽

Vol 12 (4) ◽

pp. 333-341

Author(s):

S. P. Namboothiri ◽

A. H. Manson ◽

C. E. Meek

Keyword(s):

Radar Observations ◽

Tidal Propagation ◽

Radar Echoes ◽

Tidal Data ◽

E Region ◽

Future Work ◽

Mf Radar

Abstract. Efforts have been made to extend the MF radar tidal profiles to E-region heights. The totally reflected MF radar echoes from E-region heights during daytime are known to be group-retarded and the corresponding wind and tidal data will have associated height discrepancies. The estimation of the E-region real heights (Namboothiri et al., 1993), and the elimination of the data for which the group retardation is significant, are selected as the basic criteria to extend the tidal profiles to 100-125 km. The analysis of the quiet (Ap<19) days of the winter and summer seasons of 1988/89 shows that the tidal propagation continues to higher altitudes with some changes in their pattern, e.g. longer wavelengths, compared to that in the lower altitudes. Comparison with the model profiles shows some resemblance and some disagreements. The reliability of the MF radar tidal measurements of E-region heights and the propagation of tides in this region have been discussed in the light of existing theories and other experimental observations. It is concluded that, based on the initial studies with UHF and MF systems and within the limits of the available theories, the information on tides presented here for the 100-125 km region using the MF radar observations is useful. Suggestions for future work in this direction are also given.

Download Full-text