Analysis of Hindcasting wind waves and swell off Mangalore

Abstract

SMB method has been used for hindcasting waves and swell off Mangalore, Karnataka, India, during the SW monsoon of 1968 and 1969. Significant wave characteristics, both height and period, predicted by this method compare well with the recorded data. It is found that the fetch is not a continuous one. Two generating areas are encountered (from 74 to 70ᵒ E and 70 to 64ᵒ E). Waves generated between 64 and 70ᵒE play predominant role in forming the significant wave spectrum. During peak monsoon period waves generated beyond 64ᵒE also approach Mangalore Coast with significant periods of 10-12 sec. The effect of refraction especially for waves coming from SW and NW can not be neglected. A bottom friction factor <i>f</i> = 0.05 is found to be suitable for evaluating shallow water wave characteristics at this coast. Statistical relationships for obtaining shallow water significant wave height from deep water wave characteristics are presented.