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The trend in climate and oceanic variables was investigated for the recent years (2017-2019). After a neutral phase in 2018, the Southern Oscillation Index entered a negative phase in January 2019, continuing until July 2019. This short event has been qualified as a weak El Niño event. By contrast, a positive dipole (IOD), started in 2017, continued through 2018 and was still observed at a lesser level in August 2019. In line with the IOD, from 2017 to present, warm temperature anomalies prevailed in the WIO whereas sea surface temperature fluctuated around the average in the EIO. The trend in chlorophyll concentration (SSC) was investigated in four ecoregions of the tropical Indian Ocean, distributed between 12°N and 30°S, during 1997-2019. A similar trend is observed in the four ecoregions, with SSC-depleted conditions during 2007-2014 and SSC-enhanced conditions in 2015-2019. A different pattern was observed from 1998 to 2006. Finally, following previous studies, it is shown that the intensity of two important upwelling systems of the tropical Indian Ocean fluctuate in relation to the Dipole/ENSO cycle, however in an opposite way. In the EIO, the SLP anomalies recorded in Darwin can have a predictive power by indicating the status of the Java-Sumatra upwelling in the 3 coming months.
