Osobennosti gidrodinamicheskikh protsessov v rayone Bakal'skoy kosy po dannym chislennogo modelirovaniya

Abstract

Hydrodynamic processes have a decisive influence on morphodynamics of the coastal area of seas. This paper studies, using computational modeling, characteristics of currents, sea level and wind waves in the Bakalskaya Spit area at storm situations of various types. For computational modeling the joined model ADCIRC+SWAN was used, which includes the barotropic hydrostatic model of currents ADCIRC and spectral wave model SWAN. The joined model uses an unstructured grid with a high spatial resolution. Calculations for a storm situation in the Black Sea (20–27 March, 2013) showed that the current field in the Bakalskaya Spit area varies greatly in terms of time and space. The greatest current velocities (up to 0.9 m/s) emerge between the island and the spit tip. Surges in the spit area reach up to 0.3 m. In the variation of sea level, oscillations with a period of ~ 10.5 h prevail. This period is close to that of the lowest mode of seiche oscillations in the Karkinitsky Bay. The wind waves are the most intensive at the western side of the spit, and during the storm peak, the height of significant waves hs reaches 2–2.5 m. The eastern side of the spit is less exposed to the waves. Here, the hs values are half as big. Between the spit tip and the island the maxima hs are 1 m. Matching calculations of waves performed using the joined model ADCIRC+SWAN and using the model SWAN showed that the joined model provides higher waves. At the western side of the spit, this increase in hs reaches 0.5 m