The Spatial and Temporal Impacts of Mixed Layer Depth (MLD) variations in West Sumatera Coastal Area

Abstract

This paper investigates sea surface height to geoid (SSHG) and mixed layer depth (MLD) variations in the West Sumatera Coastal Area dominated Indian Ocean Dipole (IOD) evolutions using the data of MLD and (SSHG) from 2004 to 2017. The MLD variations in West Sumatera Coastal Area are explicitly investigated through spatial and temporal variations Empirical Orthogonal Functions (EOF). In the previous research, MLD variations in these extensive ocean-atmospheric circulations mainly focused on seasonal variations. The first results of EOF mode indicate 12% of the variability and show MLD variations in West Sumatera Coastal area during boreal fall (September – November). This result indicates that seasonal variation of MLD is slightly weak to the IOD event caused by ENSO signals from atmospheric teleconnection. On the other situation, the seasonal variations of SSHG is tightly related to the Indian Ocean Dipole (IOD) evolutions. The EOF results of SSHG shows 30% variabilities and is stronger than the MLD. The weak (dominant) pattern of these MLD and SSHG variations affects a shoaling layer over the west Sumatra coastal area associated with the negative Indian Ocean during 2010. We suggest that this MLD and SSHG product could be used as a reference for future studies and predict fish productivity.