Investigating the Trends in Extreme Wave Events for Different Return Periods over Bay of Bengal, Indian Ocean

This paper investigates the spatio-temporal trends for different return periods of extremely significant wave height (SWH) in the Bay of Bengal (BOB), Indian Ocean based on a 40-yr (1979–2018) wave hindcast. High-resolution reanalysis of wind field datasets is used to force a spectral wave model WAVEWATCH III (WW3). The wave hindcast information is validated using satellite data gathered from the European Centre for Medium-Range Weather Forecast (ECMWF) Era-Interim. The model performance is adequate. Findings showed that trends for the 5–100-yr return periods of the 99th percentile wave height are significantly strong and range between 0.1[Formula: see text]m yr[Formula: see text] and 1.4[Formula: see text]m yr[Formula: see text] in the northeastern islands of the sea. Weaker trends (0.06–0.6[Formula: see text]m yr[Formula: see text]) exist in the western region of the sea while insignificant and negative trends dominate the rest waters. For the 2-yr return period, negative trends were distributed all over the sea. Temporal trend analysis for each of the return periods revealed insignificant and negative trends in all cases.