Three-dimensional numerical simulation of wind-induced barotropic circulation in the Gulf of Patras

The barotropic, wind-induced circulation, which develops in the Gulf of Patras in Western Greece during the winter, is studied using three-dimensional numerical simulations. The simulations are performed using the numerical code MIKE 3 FM (HD). The Gulf's basin is bracketed between two sills, one on the west at the opening with the Ionian Sea and the other on the east at the Straits of Rio-Antirio at the opening with the Gulf of Corinth. The simulations show that the wind-induced flow creates strong currents near the coasts, which determine the sense of rotation of the gyres that develop in the Gulf. Strong currents are also created at the Rio-Antirio Straits. The wind-induced, barotropic currents do not seem to contribute to the direct replenishment of bottom waters, which recirculate between the two sills. Depending on the wind-speed forcing of the flow, the residence time of the waters in the Gulf of Patras is estimated to range from one week to one month.