Subsurface Temperature Variability in the Tropical Indian Ocean
The subsurface temperature variability in the Tropical Indian Ocean (TIO) is examined. Asymmetry in the evolution of positive and negative phases of subsurface mode (SSM) is reported. The asymmetry in the subsurface-surface interaction during the two phases of subsurface mode and its impact on the modulation of surface features of TIO are analysed. The representation of SSM in CFSv2 is also studied. Even though the nature of the north–south dipole in TIO subsurface temperature is successfully captured by CFSv2, a rapid decay of the mode is seen in the model. It is also found that the misrepresentation of subsurface variability in CFSv2 during December–February is closely associated with the rapid decay of El Niño forced TIO warming.