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1

Currents circulation in the waters of Admiralty Bay (region of Arctowski Station on King George Island)

100%
Pruszak Z.
Polish Polar Research
|
1980
|
tom 01
|
nr 1
2

Ginace plaze

63%
Pruszak Z., Ostrowski R.
Academia. Magazyn Polskiej Akademii Nauk
|
2005
|
nr 1
24-25
3
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Relationships between coastal processes and properties of the nearshore sea bed dynamic layer

63%
Ostrowski R., Pruszak Z.
Oceanologia
|
2011
|
tom 53
|
nr 3
The paper discusses the notion of a layer of sandy sediments overlying a substratum of cohesive deposits in the coastal zone. This layer of sand is generally more mobile and is therefore conventionally referred to as the dynamic layer. Its parameters are important to coastal lithodynamic and morphodynamic processes caused by waves and currents. On the other hand, the dynamic layer is formed by nearshore hydrodynamic impact. The variability of the features of the dynamic layer on the southern Baltic dune and cliff shores in Poland is analysed on the basis of selected geological data supported by local seismo-acoustic field investigations. It appears that the conventional notion of the dynamic layer makes sense only in specific geomorphologic conditions. In such cases, mostly related to cliff shores, theoretical modelling of sediment transport should take the properties of the dynamic layer into account.
4

Groins and submerged breakwaters – new modeling and empirical experience

51%
Ostrowski R., Pruszak Z., Schonhofer J., Szmytkiewicz M.
Oceanological and Hydrobiological Studies
|
2016
|
tom 45
|
nr 1
5
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Variability and correlations of shoreline and dunes on the Southern Baltic coast (CRS Lubiatowo, Poland)

51%
Pruszak Z., Ostrowski R., Schonhofer J.
Oceanologia
|
2011
|
tom 53
|
nr 1
The paper analyses the results of field investigations into the evolution of the shoreline and dune toe positions in a multi-bar, dissipative coastal zone. The correlations between the changes in the shoreline and the dune toe range from −0.4 to 0.8. It is most often the case that the dune toe is stable while the shoreline moves. Consistent cross-shore migration is slightly more likely to happen than the divergent or convergent movements of both lines. Shoreline retreat and advance attain respective rates of 0.7 m day−1 and 0.4 m day−1. Deep-water wave energy of about 50 kJ m−1 constitutes the boundary between shore accumulation and erosion.
6
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Application of Dean's curve to investigation of a long-term evolution of the Southern Baltic multi-bar shore profile

51%
Cerkowniak G. R., Ostrowski R., Pruszak Z.
Oceanologia
|
2017
|
tom 59
|
nr 1
The paper presents the results of studies on the long-term evolution of the multi-bar cross-shore profiles. The analysis is focused on time-dependent variability of shoreline position, a modified parameter A of the conventional Dean's equation and a parameter F describing the amount of nearshore sediment resources in the multi-bar cross-shore profile. The study also deals with interrelationships between these quantities. The analysis is carried out using field data collected at Lubiatowo, Poland, on the dissipative shore, representative for the south Baltic. The considered coastal segment is found to be stable in the long-term scale. The results of analysis show that the parameter A can either increase or decrease together with the shoreline advance. It is concluded that the shoreline position change is a parameter unsatisfactorily representative for behaviour of the seashore. The use of the Dean's approximation for estimation of the sediment resources F on the multi-bar seashore profiles is found reasonable to eliminate the effects of peculiarities of such shores.
7
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Megascale rhythmic shoreline forms on a beach with multiple bars

51%
Pruszak Z., Rozynski G., Szmytkiewicz P.
Oceanologia
|
2008
|
tom 50
|
nr 2
183-203
The study, carried out in 2003 and 2006 at the Lubiatowo Coastal Research Station (Poland), located on the non-tidal southern Baltic coast (tidal range < 0.06 m), focused on larger rhythmic forms (mega-cusps) with wavelengths in the interval 500 m > Lc > 20 m. Statistical analyses of detailed shoreline configurations were performed mostly with the Discrete Wavelet Transform method (DWT). The beach is composed of fine sand with grain diameter D50 ≈ 0.22 mm, which produces 4 longshore sandbars and a gently sloping seabed with β = 0.015. The analysis confirms the key role of bars in hydro- and morphodynamic surf zone processes. The hypothesis was therefore set up that, in a surf zone with multiple bars, the bars and mega-scale shoreline rhythmic forms form one integrated physical system; experimental evidence to substantiate this hypothesis was also sought. In such a system not only do self-regulation processes include swash zone phenomena, they also incorporate processes in offshore surf zone locations. The longshore dimensions of large cusps are thus related to the distances between periodically active large bed forms (bars). The spatial dimension of bar system activity (number of active bars) depends, at a given time scale, on the associated hydrodynamic conditions. It was assumed that such a time scale could include either the development and duration of a storm, or a period of stable, yet distinct waves, capable of remodelling the beach configuration. The indentation to wavelength ratio of mega-cusps for the studied non-tidal dissipative environment may be one order of magnitude greater than for mesotidal, reflective beaches.
8
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Long period oscillations in the longshore current on a sandy, barred coast investigated with singular spectrum analysis

51%
Kaczmarek J., Rozynski G., Pruszak Z.
Oceanologia
|
2005
|
tom 47
|
nr 1
The presence of infragravity waves in nearshore regions can be sought in the records of both water levels and wave-driven longshore currents. For this reason, time series of such currents in close proximity to the shoreline were analysed using Singular Spectrum Analysis (SSA). Simultaneously, the results obtained with this method were confronted with the output of Discrete Wavelet Transform (DWT), which had previously been applied to this data. The records of longshore currents were collected on a daily basis during field experiments in the autumns of 2002 and 2003 with sampling rates of 3 Hz and 0.5 Hz. This produced a large data set that allowed for the use of an advanced signal processing technique, capable of extracting patterns characteristic of low-, medium- and high-frequency bands. It provided similar evidence to that produced by DWT for the existence of infragravity waves along a dissipative coast with multiple bars. The study also demonstrated the utility of SSA for studies on coastal hydrodynamics. It also showed up the better user-friendliness of DWT in terms of pattern extraction and interpretation. On the other hand, SSA demonstrated a higher precision of pattern extraction once the DWT output was known, which is a manifestation of the synergy of the two methods when applied jointly.
9
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Shallow-water wave energy dissipation in a multi-bar coastal zone

45%
Pruszak Z., Szmytkiewicz P., Ostrowski R., Skaja M., Szmytkiewicz M.
Oceanologia
|
2008
|
tom 50
|
nr 1
43-58
The paper presents the results of studies of wave transformation on a multi-bar cross-shore profile of the southern Baltic Sea. The field investigations of wave motion were carried out using an offshore wave buoy and string wave gauges at the IBW PAN Coastal Research Station, Lubiatowo (Poland). These experimental results were used to validate statistical relationships between characteristic wave parameters in the coastal region and to assess wave energy dissipation in the surf zone. Asimple model for calculating the residual nearshore wave energy is proposed and tested versus the data collected in situ.
10
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Hydrology and morphology of two river mouth regions (temperate Vistula Delta and subtropical Red River Delta)

45%
Pruszak Z., Van Ninh P., Szmytkiewicz M., Hung N. M., Ostrowski R.
Oceanologia
|
2005
|
tom 47
|
nr 3
The paper presents a comparative analysis of two different river mouths from two different geographical zones (subtropical and temperate climatic regions). One is the multi-branch and multi-spit mouth of the Red River on the Gulf of Tonkin (Vietnam), the other is the smaller delta of the river Vistula on a bay of the Baltic Sea (Poland). The analysis focuses on the similarities and differences in the hydrodynamics between these estuaries and the adjacent coastal zones, the features of sediment transport, and the long-term morphodynamics of the river outlets. Salinity and water level are also discussed, the latter also in the context of the anticipated global effect of accelerated sea level rise. The analysis shows that the climatic and environmental conditions associated with geographical zones give rise to fundamental differences in the generation and dynamic evolution of the river mouths.
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