The El Niño-Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) phenomena are major modes of interannual climate variability in the tropics, significantly affecting climate conditions on regional and global scales. JMA operates the Ocean Data Assimilation System and the El Niño Prediction System (an ocean-atmosphere coupled model) for monitoring and prediction of ENSO. JMA monitors also the IOD phenomena as well as ENSO with our Ocean Data Assimilation System. Monthly diagnosis reports, ENSO and IOD monitoring products, ENSO and IOD indices and El Niño outlooks are available on this page.
Notice: Outgoing Longwave Radiation (OLR) data for figures 8 and 9 in El Niño Monitoring were replaced with the new NOAA CPC Blended OLR data in October 2023. (Supplementary information)
