Altimetric Observations and Model Simulations of Coastal Kelvin Waves in the Bay of Bengal

Abstract

Wavelet analyses of sea surface height (SSH) obtained from Simple Ocean Data Assimilation (SODA) reanalysis, satellite altimetry derived SSH anomalies during 1993–2006, and HYbrid Coordinate Ocean Model (HYCOM) simulations of SSH during 2003–2006 in the tropical Indian Ocean reveal dominant annual Kelvin waves in the equatorial wave guide and dominant semiannual Kelvin waves off Sumatra coast and along the coastal Bay of Bengal. This study reveals variability in the propagation of upwelling Kelvin wave during winter and summer monsoons and downwelling Kelvin wave during monsoon transitions. Further, the winter transition downwelling Kelvin wave largely affects the coastal circulation of India.

Keywords:

• Coastal Kelvin waves
• Indian Ocean
• altimetry
• HYCOM
• SODA

Acknowledgements

This work was supported by the Office of Naval Research (ONR) Award# N000141210454 awarded to BS. We thank Benjamin Giese for making available the Simple Ocean Data Assimilation (SODA) reanalysis, and Jay F. Shriver for providing HYCOM simulations. The altimeter products were distributed by AVISO. This has the NIO contribution No. 5178.