STUDY OF SEA SURFACE HEIGHT AND OCEAN HEAT CONTENT IN THE WEST SUMATRA TO THE SOUTH JAVA SEAS IN THE INDIAN OCEAN DIPOLE (IOD) EVENT 2010 AND 2012

• Main Author: Khairun Nisa', A.R.
• Format: Theses
• Language: Indonesia
• Subjects: Ilmu kebumian
• Online Access: https://digilib.itb.ac.id/gdl/view/61943
• Institution: Institut Teknologi Bandung

In the forming process of the Indian Ocean Dipole (IOD), not only the temperature on the surface and the subsurface layer of the sea has changed, several other parameters such as sea level, heat content, and wind have also changed. This study aims to determine the condition of these parameters in the 2010 negative IOD (n-IOD) and 2012 positive IOD (p-IOD) events, especially in the West Sumatra to South Java seas. The HYbrid Coordinate Ocean Model (HYCOM) reanalysis model data is used for sea surface temperature and elevation, wind speed (zonal and meridional) from ECMWF – ERA5, while ocean heat content data is calculated from temperature data. Temperature anomaly data will be present using spatial plots and Hovmöller diagrams, for other parameters presented using spatial plots. In the 2010 nIOD event, the positive temperature anomaly in the subsurface layer four months before the IOD event while, in the 2012 pIOD event the negative temperature anomaly in the subsurface layer had formed one month before the onset of the IOD event. The temperature changes had followed by changes in SSHA and depth of T20. Changes in the value of SSHA and depth of T20 in nIOD 2010 have a higher value than pIOD 2012. The pattern of changes in ocean heat content in 2010 shows the influence of seasonal variations, but this does not appear in 2012. Weakening or strengthening of the easterly wind plays a role in the formation or decay of temperature anomalies in IOD events.