The Oceanic Niño Index (ONI) is a monthly measure of the El Niño-Southern Oscillation. It is calculated as a 3-month running mean of sea surface temperature (SST) anomalies in the Niño 3.4 region (5°N–5°S, 120°W–170°W), using 30-year base periods updated every 5 years. ONI values may change for up to two months after initial posting due to data filtering.
Usage
data(oni)Format
An ea_data object with:
- data
A tibble with columns:
- year
Year (numeric)
- month
Month (numeric, 1–12)
- value
Three-month average sea surface temperature (SST, °C)
- anomaly
SST anomaly (°C)
- meta
A named list with:
- data_type
Character. "Oceanic Niño Index (ONI)"
- region
Character. "Pacific"
- location_descriptor
Character. "Niño 3.4 region"
- units
Character. "°C"
- species
Character.
NA_character_(not applicable)- source_citation
Character. NOAA CPC, see links above
- original_value_col
Character. Name of value source column, e.g. "val"
Details
For more information, see NOAA ONI and NOAA ENSO SST.