Importance and origin of halosteric contribution to sea level change in the southeast Indian Ocean during 2005–2013: local forcing and inter-basin linkages

In the past two decades, steric sea level change has been identified as one of the major contributors to the observed sea level rise. This contribution is temporally and spatially varying. Over much of the global ocean, thermosteric effect has been found to be generally more important than halosteric effect. Based on altimeter and Argo data during the 2005-2013 period, we found that the central-eastern part of the South Indian Ocean stood out as the region that had the largest halosteric contribution to sea level change in the entire global ocean with a magnitude that is larger than that of thermosteric contribution. We discuss the halosteric and thermosteric changes in this region in relation to local forcing, the linkage with the western Pacific Ocean, and the potential role of marginal seas between the Pacific and Indian Oceans in the context of regional interannual and decadal climate variability.