Contribution of Southern Indian Ocean swells on the wave heights in the Northern Indian Ocean-A modeling study

摘要

Waves are important driving forces that have important ramifications for physics, chemistry and biology of the coastal and open ocean. An attempt is made to study the swell propagation from Southern Indian Ocean and to account for its contribution to the local wave climate in Northern Indian Ocean. The third generation ocean wave model, MIKE 21 SW is implemented and validated to simulate wave heights for the period starting from September 2008 to August 2009 for the Indian seas. Simulations were carried out by modifying the analyzed winds over the model domain (30°E-120°E and 60°S-30°N). It was found that Southern Indian Ocean swells play an important role in determining the Northern Indian Ocean wave climate. Under the influence of the southwest summer monsoon winds, the swell dominance on the local wave climate drops in the Bay of Bengal but not as much as in the Arabian Sea due to the strong and persistent southwest winds during the summer monsoon. During the rest of the year, the swell is a dominant factor in determining the wave climate of the Northern Indian Ocean.