Title

Title	Quarterly Relative Oceanic Niño Index (RONI) - Historical El Niño / La Niña episodes (1950–2025)	?
Author	NOAA / National Weather Service / National Centers for Environmental Prediction Climate Prediction Center	?
Abstract	Warm (EL) and cold (LA) periods based on a threshold of +/- 0.5°C for the Relative Oceanic Niño Index (RONI), using the 1991–2020 base period [3 month running mean of ERSST.v5 SST anomalies in the Niño 3.4 region (5°N–5°S, 120°–170°W) with average tropical mean (20°N–20°S) SST anomalies subtracted. The difference is then adjusted so the variance equals the original Niño 3.4 index]. N represents the ENSO neutral periods. For analytical purposes, SASSCAL extracted four quarters: JFM (January-February-March), AMJ (April-May-June), JAS (July-August-September) and OND (October-November-December).	?
Citation	https://journals.ametsoc.org/view/journals/clim/30/20/jcli-d-16-0836.1.xml	?

Dataset

Document Reference Date Type	creation	?
Date	2026-07-01	?
Language	English	?
Online Linkage	https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/	?

Dataset Classification

Type	EXCEL (*.xls, *.xlsm,*.xlsx)	?
Resource type	Dataset	?
External source	yes	?

Metadata

Metadata Contact Person	Thompson, Sylvia	?
Metadata Date Stamp	2026-07-03	?

Identifier

Internal identifier

sdp_doc_data_7589 (Link)