Mechanisms of Interannual Variability of Ocean Bottom Pressure in the Southern Indian Ocean

The study of ocean bottom pressure (OBP) helps to understand the changes in sea level budget and deep circulation. In this study, characteristics mechanisms interannual OBP variability Southern Indian Ocean are examined using Gravity Recovery Climate Experiment (GRACE) satellite data from 2003 2016. Results show that there two energetic centers (50°–60°S, 40°–60°E 45°–60°S, 80°–120°E). magnitudes at have strong on time scales, their values larger during austral summer (NDJF) winter (JJAS). Atmospheric forcing plays an important role local variability. high (low) (SLP) over benefits positive (negative) anomalies via convergence (divergence) Ekman transport driven by wind. Such SLP related Annular Mode (SAM), Oscillation (SO) dipole (IOD). SAM can influence both winter, while SO IOD correlations with respectively. These results validated a mass-conservation model, which further confirms importance atmospheric variations.