Sea Level Anomalies in the Tropical Indian Ocean during Two Contrasting Southwest Monsoon Years

Abstract

The sea level anomalies (SLA) in the tropical Indian Ocean (TIO) during two consecutive contrasting southwest monsoon years of 2002 (deficit) and 2003 (normal) are examined using multi-satellite measurements. The rainfall anomalies over the TIO in the month of July show distinct patterns during these two years. The more consistent patterns analogous to rainfall anomalies are reflected in the freshwater flux anomalies which is one of the major contributors of the local sea level change. As a result, the SLA shows distinct features in the north Indian Ocean during these two years. The surface atmospheric convergence and divergence patterns in the TIO are also investigated using multi-satellite wind vectors which are supposed to be correlated with the southwest monsoon rainfall and a key component of sea level change. The results suggest that the eustatic effect and near surface convergence/divergence of winds have significant impact on SLA locally.