Extreme bottom velocities induced by wind wave and currents in the Gulf of Gdańsk

Abstract

The principal goal of this study is to get some preliminary insights about the intensity of water movement generated by wind waves, and due to the currents in the bottom waters of Gulf of Gdańsk, during severe storms. The Gulf of Gdańsk is located in the southern Baltic Sea. This paper presents the results of analysis of wave and current-induced velocities during extreme wind conditions, which are determined based on long-term historical records. The bottom velocity fields originated from wind wave and wind currents, during analysed extreme wind events, are computed independently of each other. The long-term wind wave parameters for the Baltic Sea region are derived from the 44-year hindcast wave database generated in the framework of the project HIPOCAS funded by the European Union. The output from the numerical wave model WAM provides the boundary conditions for the model SWAN operating in high-resolution grid covering the area of the Gulf of Gdańsk. Wind current velocities are calculated with the M3D hydrodynamic model developed in the Institute of Oceanography of the University of Gdańsk based on the POM model. The three dimensional current fields together with trajectories of particle tracers spreading out of bottom boundary layer are modelled, and the calculated fields of bottom velocities are presented in the form of 2D maps. During northerly winds, causing in the Gulf of Gdańsk extreme waves and most significant wind-driven circulation, the wave-induced bottom velocities are greater than velocities due to currents. The current velocities in the bottom layer appeared to be smaller by an order of magnitude than the wave-induced bottom orbital velocities. Namely, during most severe northerly storms analysed, current bottom velocities ranged about 0.1-0.15 m/s, while the root mean square of wave-induced near-seabed velocities reached maximum values of up to 1.4 m/s in the southern part of Gulf of Gdańsk.

Wind Waves and Beach Inundation Width Modelling for Studying Curonian Spit National Park Foredune Stability

“…Модель SWAN для расчета параметров ветрового волнения в прибрежной зоне моря широко используется в мире и доказала свою эффективность [6][7][8]. С использованием данной модели в юго-восточной части Балтийского моря ранее производились расчеты различных параметров ветрового волнения [9][10][11]. Модель была верифицирована для использования в Балтийском море [11][12][13], в том числе в прибрежной зоне.…”

Assessment of the potential for dredged material dispersal from dumping sites in the Gulf of Gdańsk

“…The three-dimensional current fields together with trajectories of particle tracers spreading out of bottom boundary layer were modeled by Cieślikiewicz et al (2017). They calculated fields of bottom velocities due to both currents and wind-wave motion.…”

“…The root mean square of wave induced near-seabed velocities (u rms ) reached the values of up to 0.5 m s −1 over site 1 and ranged between 0.5 and 0.8 m s −1 over site 2. During most severe northerly storms analyzed in Cieślikiewicz et al (2017), the maximum bottom current velocities of up to 0.3 m s −1 were computed by M3D along the Hel Peninsula on its northern (open sea) side. SWAN modeled the maximum wind wave bottom orbital velocity values u rms of up to 1.4 m s −1 , in the narrow strip adjacent to the Vistula Sandbar along the Gulf's south-eastern coast.…”

Editorial—the 8th International Workshop on Modeling the Ocean (IWMO 2016) in Bologna, Italy, June 7–10, 2016

“…The study shows that standard interpolation of tidal velocities can introduce errors in tidal ellipses and demonstrates how the new method works for simulations of the M2 tide along the Korean coast using ROMS. Cieślikiewicz et al (2017) used the wave model SWAN and a POM-based hydrodynamic model to study windwave-induced currents in the Gulf of Gdańsk. Hindcast models of the Baltic Sea provide boundary conditions for the local high-resolution models.…”

“…Coastal modeling and process studies (Bie et al 2017;Ezer 2017;Ezer and Atkinson 2017;Liao et al 2017;Lu et al 2017, Trotta et al 2017; (3.) Surface wave modeling (Clementi et al 2017;Cieślikiewicz et al 2017;Gic-Grusza and Dudkowska 2017; Guo and Sheng 2017;Sun et al 2017); (4.) Biogeochemicalphysical coupled models (Mussap et al 2017, Luo et al 2017.…”