An Appraisal of Indian Ocean Dipole variability and its linkage with ENSO: Future perspective

The Indian Ocean Dipole (IOD) is a coupled ocean-atmosphere phenomenon marked by anomalous equatorial Sea Surface Temperature (SST) variations, shaping global climate patterns. Numerous instrumental records and model simulations demonstrate the IOD mechanisms on a centennial scale. However, IOD trends, variability, and connection with other climatic phenomena are still debatable and need further study. This study synthesizes instrumental and high-resolution proxy records to trace IOD variability from present to deep geological time scales, evaluating its role in the Indian Ocean climate dynamics and global teleconnections.Previous studies document that the eastern equatorial pole is sensitive to capture IOD signals and makes a shallower thermocline during positive IOD. Additionally, long-term proxy-based studies of IOD variability are limited and show conflicting results regarding IOD-like mean state during the Last Glacial Maximum (LGM) and the Holocene. Predictions of IOD variability are still preliminary, with inconsistent accuracy and varied success. Therefore, more emphasis is needed to improve model simulations and enhance proxy data for the longer time scale (glacial-interglacial cycle) to improve IOD predictions. Furthermore, the study required the influence of the Pacific and Atlantic Oceans on the Indian Ocean Dipole (IOD) and the Indian monsoon. Key words: El-Niño Southern Oscillation, Indian Ocean Dipole, Indian monsoon, Indonesian through flow, Walker circulations