Summary of Abstract Submission

Abstract Submission No. IO50-04-0052PresentationPoster

APPLICATION OF WIND-FORCED COASTAL-TRAPPED-WAVE THEORY TO THE CENTRAL WEST COAST OF INDIA

Amol P*1, Fernando V2, Pednekar P2, Jai Singh2

1 Indian Institute of Science, India
2 National Institute of Oceanography, India

ABSTRACT :

A linear coastal-trapped-wave (CTW) model is used to examine the effects of large-scale winds, with time scale ranging from a few days to a few weeks, on the West India Coastal Current (WICC), particularly on the shelf off the central west coast of India. We show that unlike the seasonal cycle of WICC, which is primarily forced by the winds along the east coast of India, the high-frequency WICC is mostly driven by the west-coast winds. Nevertheless, the influence of winds as far as Sri Lanka and east coast of India cannot be neglected. Simple numerical experiments with the CTW model show that the strong current observed at Goa (15◦N) compared to Bhatkal (13◦N) and Jaigarh (17◦N) is due to two factors: 1) the superposition of local and remote CTWs, and 2) the widening of shelf width north of Goa, which decreases the amplitude of the currents poleward of Goa. If the local winds are weak, the amplitude of current decreases poleward due to friction, and the current at the south lead the north. We also note that the observed phase difference between sea level and alongshore current at Goa could be attributed to propagation of remotely-forced higher-order modes of CTWs.