The Relative Oceanic Niño Index (RONI) is a tool used for comparing current and historical El Niño and La Niña events, as cited in the NOAA/NCEI ENSO SST Indicators Guide.
Notes on verification
Core claim about RONI's purpose is strongly corroborated by NOAA CPC's official announcement and the peer-reviewed L'Heureux et al. 2024 paper. However, the specific citation to a 'NOAA/NCEI ENSO SST Indicators Guide' document title could not be independently verified, though NCEI does host related ENSO SST resources. [tier=gold indep_score=0.867 clusters=3 claim_tier=notable]
Sources
- El Niño Today | El Nino Theme Page - A comprehensive Resource (seed:science_and_space)
- https://ggweather.posthaven.com/relative-oceanic-nino-index-roni-replacing-oni-as-enso-metric (corroboration)
- https://weather.gov/media/notification/pdf_2026/pns26-05_Relative_ONI.pdf (corroboration)
- https://journals.ametsoc.org/view/journals/clim/37/4/JCLI-D-23-0406.1.xml (corroboration)