Wind-driven Waves Pattern in the Caspian Sea

An accurate knowledge and understanding of wind-driven wave characteristics is one of basic requirements in marine activities and environmental studies. The present research deals modeling wind-driven wave with irregular triangular computational mesh grid in the Caspian Sea. Then, the wind-driven wave field of the Caspian Sea has been analyzed in the 2000 - 2020 period. For this purpose, the SWAN numerical model with irregular computational mesh grid was used to simulate wind-driven wave characteristics using Era-Interim reanalysis data with accuracy of 0.125 degree. The results of the modeling were validated with the measurements data in Nowshahr, Amirabad and Anzali buoys position. To increase the forecast accuracy, the model with different AGROWTH and the Whitecapping coefficients was evaluated in the Caspian Sea. Then the monthly average sea surface wind and the significant wave height field extracted for a period of 20 years. Also, dominant wind-driven wave patterns were extracted using the Empirical Orthogonal Functions (EOF) analysis method in the study area. The results show that three first main components of the EOF analysis are respectively about 70%, 20% and 5% of the total anomaly pattern of the wind-driven waves in the Caspian Sea. Therefore we can interpret separately the effect of the local waves on the general wind-driven wave pattern of the Caspian Sea.