Analysis of temporal and spatial characteristics of waves in the Indian Ocean based on ERA-40 wave reanalysis

作者：Zheng, Chong Wei; Li, Chong Yin^*

来源：Applied Ocean Research, 2017, 63: 217-228.

DOI：10.1016/j.apor.2017.01.014

• Indian ocean
• Swell
• Interannual variability
• Interdecadal variability
• Intraseasonal oscillation
• Propagation

Based on the 45-year (09/1957-08/2008) European Centre for Medium-Range Weather Forecasts (ECMWF) Reanalysis (ERA-40) wave reanalysis dataset, this study analyzes interannual and interdecadal variabilities and intraseasonal oscillations of sea surface wind speed (WS), wind sea wave height (H-w), swell wave height (H-s) and significant wave height (H-s) in the Roaring Forties and tropical waters of the Indian Ocean, to determine swell propagation characteristics. The results show: (1) monthly variabilities of H-s in the Roaring Forties are in good agreement with those in tropical waters of the Indian Ocean; swell plays a dominant role in mixed waves throughout most of the Indian Ocean; and WS, H-s, and H-s exhibit a significant increasing trend over the 45-year study period. (2) H-s in the Roaring Forties and tropical waters of the Indian Ocean share a common period of 9.8-10.4 years on an interdecadal scale; and WS and H-s in the Roaring Forties and H-s in the tropical waters of the Indian Ocean share a common period of approximately 8 days (weekly oscillation) on an intraseasonal scale. (3) Swell of the Roaring Forties needs approximately 30 h to fully respond to the wind in this region. Approximately 84 h are required for H-s to propagate from the Roaring Forties to the tropical waters of the south Indian Ocean, While it takes approximately 132-138 h for H-s to propagate from the Roaring Forties to the tropical waters of the north Indian Ocean.

• 出版日期2017-2
• 单位中国人民解放军海军大连舰艇学院; 中国科学院大气物理研究所