Search

Recent numerical models have simulated the equatorial Indian Ocean twin gyres. However, there is no strong observational evidence for the existence of these gyres. Satellite technology and filter techniques are explored in this study to provide observational evidence for the existence of these gyres. The westward-propagating Rossby waves in the equatorial Indian Ocean, filtered from the Topex/Poseidon sea surface height anomalies (SSHA) showed the twin gyre structure which coincides with the model-simulated gyres. The present study further addresses the interannual variability of these gyres, especially during the Indian Ocean Dipole (IOD) years. The anomalous wind stress curl is found to drag the annual Rossby waves during the IOD years in the region 78°E-88°E. The downwelling favourable wind stress curl deepens the thermocline and increases SSHA and sea surface temperature. [ABSTRACT FROM AUTHOR]