01-05 December 2025
INCOIS, Hyderabad, India.
| Abstract Submission No. | ABS-04-0059 |
| Title of Abstract | Heat content distribution in the southeastern Indian Ocean during the hiatus period |
| Authors | Hiroki Iwasa*, Yukio Masumoto |
| Organisation | The University of Tokyo |
| Address | Minamikoshigaya 4-8-9-1013 Koshigaya, Saitama, Japan Pincode: 3430845 E-mail: hiwasa@eps.s.u-tokyo.ac.jp |
| Country | Japan |
| Presentation | Oral |
| Abstract | It has been known that there exists decadal variability in the upper ocean heat content in the eastern Indian Ocean. During the hiatus period in the first decade of the 21th century, the southeastern Indian Ocean (SEIO) experienced unprecedented warming in the upper layer temperature as a part of decadal variability. Horizontal distribution of the temperature trend during the hiatus period indicates the wide area of positive value in the southeastern Indian Ocean. Several studies have identified possible causes for this heat content increase during the hiatus period: one is the enhanced Indonesian throughflow and another is the local wind forcing over the Indian Ocean as well as the remote influence from the Pacific Ocean. However, detailed processes and mechanisms causing the temperature trend distribution within the SEIO have not been revealed yet. In this study, as the first step toward better understanding of processes and mechanisms responsible for the temperature trend distribution within the SEIO, a heat budget analysis focusing on the hiatus period is conducted by using an OGCM output. Heat budget analysis is applied to several key areas in the SEIO, where large increase of the heat content is observed. In one of these areas away from the western Australia, in which the large temperature trend can be seen only during the hiatus period, the meridional heat convergence is a significant component for the heat accumulation. This meridional advection is caused by the anomalous southward current at the norther face of the region. In the presentation, the cause of that anomalous southward current and the quantitative analysis of the contribution of mesoscale eddies for the heat content variability in the SEIO will be discussed. |
| Are you part of IIOE-2 endorsed project | no |
| Keywords | hiatus period, heat content distribution |
| For Awards | no |