Variability of the South Java Current from 1993 to 2021, and its relationship to ENSO and IOD events

The variability of the South Java Current (SJC) was observed by using reanalysis data spanning the years 1993 to 2021. This was done in order to determine whether or not the SJC was more influenced by the Indian Ocean Dipole (IOD), the El Niño-Southern Oscillation (ENSO), or a combination of the two. Employing empirical orthogonal function (EOF) analyses, we were able to determine that the time series of the principal component in the first mode (PC1) had an association with one of these occurrences. During the northwest monsoon in December, January, and February (DJF), it would appear that the IOD has a greater impact on the SJC than ENSO does, with a correlation of more than 0.8. During the first transition, which occurs in March, April, and May (MAM), the time series PC1 demonstrates that the SJC has a greater association with the ENSO (coefficient correlation more than 0.7). The study demonstrates that the PC1 has a negative association with both the IOD and the ENSO during the months of JJA, with a coefficient value less than 0.4. The JJA's SJC, however, is positively influenced by the coastal Kelvin wave in the vicinity of western Sumatra and southern Java. Moreover, the magnitude of the SJC, which was observed in DJF months, is affected by the Rossby wave that is moving in a westward direction south of 9˚S.