Surface wind-waves properties during Indian summer monsoon is investigated based on measured data at 9-15 m water depth at 4 sites in nearshore waters of the eastern Arabian Sea. Significant wave height varied from 0.7 to 5.5 m with average ratio of crest height of wave to height of the same wave as 0.58 to 0.67. Extreme crest height is 1.23 to 1.35 times significant wave height. Measured waves were predominantly swell. Numerical wave model could estimate the wave height well during wave growth.

Using measured, modeled and reanalysis wave data and reanalysis wind data, we show that the Indian Ocean Dipole (IOD) plays a role in the variability of wave climate of the eastern Arabian Sea (AS). The change in wind field over the AS due to IOD influences the generation or dissipation of wave field and hence causes the decrease in northwest short period waves during positive IOD and increase during negative IOD.

The nearshore wave characteristics are presented during the active sea/land breeze period based on data measured at 5 m and 15 m water depth in the eastern Arabian Sea. Prior to the sea breeze, the wave field is dominated by swell and during the sea breeze, wind-sea dominates with superimposed swell. Reduction in the wave height of wind-sea is around 20 % and that of the swell is around 10 % from 15 m to 5 m water depth.