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Calculation of Wave Run-up Height in South Baltic Sea: Case Study at Coastal Research Station at Lubiatowo, Poland

Morawski M., Różyński G., Szmytkiewicz P.

Archives of Hydro-Engineering and Environmental Mechanics

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2018

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Vol. 65, nr 3

203--291

EN

The paper presents recent investigations of beach run-up phenomena at the Coastal Research Station of the Institute of Hydro-Engineering of the Polish Academy of Sciences at Lubiatowo, Poland. The local beach is typical of open-sea coasts of the south Baltic Sea, featuring multiple longshore bars that form predominantly dissipative systems. Measurements were taken to verify the existing formulas for the run-up height, bearing in mind that they had been derived for entirely different, oceanic conditions. The results indicate that these formulations can be adapted to south Baltic Sea conditions. This however, will require significantly larger data sets, which we intend to obtain in the near future.

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An integrated wave modelling framework for extreme and rare events for climate change in coastal areas – the case of Rethymno, Crete

Tsoukala V. K., Chondros M., Kapelonis Z. G., Martzikos N., Lykou A., Belibassakis K., Makropoulos C.

Oceanologia

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2016

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No. 58 (2)

71--89

EN

Coastal floods are regarded as among the most dangerous and harmful of all natural disasters affecting urban areas adjacent to the shorelines. Rapid urbanization combined with climate change and poor governance often results in significant increase of flood risk, especially for coastal communities. Wave overtopping and wave run-up are the key mechanisms for monitoring the results of coastal flooding and as such, significant efforts are currently focusing on their predicting. In this paper, an integrated methodology is proposed, accounting for wave overtopping and wave run-up under extreme wave scenarios caused by storm surges. By taking advantage of past and future climatic projections of wind data, a downscaling approach is proposed, utilizing a number of appropriate numerical models than can simulate the wave propagation from offshore up to the swash zone. The coastal zone of Rethymno in Greece is selected as a case study area and simulations of wave characteristics with the model SWAN for the period 1960–2100 in the offshore region are presented. These data are given as boundary conditions to further numerical models (MIKE21 PMS and HD) in order to investigate the spatial evolution of the wave and the hydrodynamic field in intermediate and shallow waters. Finally, the calculated wave height serves as input to empirical formulas and time dependent wave propagation models (MIKE21 BW) to estimate the wave run-up and wave overtopping (EurOtop). It is suggested that the proposed procedure is generic enough to be applicable to any similar region.

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Motion of water and sediment due to non-breaking waves in the swash zone

Kapiński J., Ostrowski R.

Oceanologia

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2012

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No. 54 (2)

175-197

EN

A long wave run-up theory is applied to the modelling of wave-induced flow velocities, sediment transport rates and bottom changes in a swash zone. First, the properties of the water tongue motion and the resulting lithodynamic response are analysed theoretically. Next, an attempt is made to run the model for the natural conditions encountered on the southern Baltic Sea coast. The Lagrangian swash velocities are used to determine the Eulerian phase-resolved bed shear stresses with a momentum integral method, after which the motion of sand is described by the use of a two-layer model, comprising bedload and nearbed suspended load. Seabed evolution is then found from the spatial variability of the net sediment transport rates. The results presented are limited to cases of the small-amplitude waves that seem to be responsible for accretion on beaches.

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On the transformation of long gravity waves on a sloping beach

Szmidt J. K., Hedzielski B.

Oceanologia

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2010

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No. 52 (3)

363--389

EN

The transformation of long water waves arriving at a sloping beach is investigated. An approximate theory is presented for plane periodic waves propagating in water of non-uniform depth. The theoretical description of the phenomenon, based on certain kinematic assumptions, is formulated in the material variables, and the solution is constructed by applying the Hamilton variational principle. In order to assess the accuracy of the formulation and to learn more about long wave transformation, experimental measurements were carried out in a laboratory flume. In the experiments, a water wave, generated by a piston-type wave maker placed at one end of the flume, propagated towards a rigid inclined ramp installed at the other end of the flume. The wave transformation along the direction of its propagation was recorded by a set of wave gauges installed along the flume. The wave run-up on the sloping beach was measured with a special conductivity gauge placed alongside the ramp. Comparison of the theoretical results with experimental data indicates that the proposed theoretical formulation provides a good description of the main features of wave transformation behaviour over a sloping beach, except in the vicinity of the shore point, where some discrepancies occur.

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Run-Up of Linear Long Waves on Uniform Slope in Lagrangian Description

Chybicki W.

Archives of Hydro-Engineering and Environmental Mechanics

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2006

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Vol. 53, nr 2

97-104

EN

The case of linear, two-dimensional long waves on a uniform slope is considered. It is assumed that the fluid is nonviscous and incompressible. In the present paper the description of the long wave proposed by Wilde (Wilde, Chybicki 2004) is based on the fundamental assumption that the vertical material lines of fluid remain vertical during the entire motion. The equations of motion are derived with the help of a variational formulation of the problem. The Lagrangian is the difference between the kinetic and potential energy of the fluid. In the paper a correction followed from dispersion to the results obtained by Shuto is presented.