Strengthened Indonesian Throughflow Drives Decadal Warming in the Southern Indian Ocean.

Remarkable warming of the Southern Indian Ocean during the recent two decades is assessedusing a heat budget analysis based on the Estimating the Circulation and Climate of theOcean version 4 release 3 model results. The annual mean temperature averaged in theupper-700 m Southern Indian Ocean during 1998-2015 has experienced significant warmingat a rate of 1.03×10−2∘C/year. A heat budget analysis indicates that the increase is mostlydriven by decreased cooling from net air-sea heat flux and increased warming from heatadvection. Increased Indonesian Throughflow advection is the largest contributor to warmingthe upper 700 m of the Southern Indian Ocean, while the reduction of surface turbulent heatflux is of secondary importance. These results expand our understanding of the decadalheat balance in the Indian Ocean and of Indo-Pacific decadal climate variability. [ABSTRACT FROM AUTHOR]