Climate indices — available indices

The shipped indices, one canonical source per id. Pass the id(s) in variables= (e.g. variables=["oni", "nao"]). The units column is degC for SST-anomaly indices and std for the standardised pattern indices. The list below mirrors the bundled climate_indices_data_catalog.yaml; query it live with earthlens.climate_indices.Catalog().available().

id	source	dialect	units	description
oni	noaa-psl	psl	degC	Oceanic Niño Index (3-month running mean of Niño 3.4 ERSSTv5 SST anomaly)
nina34	noaa-psl	psl	degC	Niño 3.4 sea-surface-temperature anomaly
soi	noaa-psl	psl	std	Southern Oscillation Index
nao	noaa-psl	psl	std	North Atlantic Oscillation (CPC)
ao	noaa-psl	psl	std	Arctic Oscillation
pna	noaa-psl	psl	std	Pacific/North American teleconnection pattern
pdo	noaa-psl	psl	std	Pacific Decadal Oscillation
tni	noaa-psl	psl	degC	Trans-Niño Index
censo	noaa-psl	psl	std	Bivariate ENSO index (CENSO)
amo	knmi-climexp	climexp	degC	Atlantic Multidecadal Oscillation (detrended, ERSSTv5)

Sources and dialects

• noaa-psl (psl dialect) — NOAA PSL correlation/<index>.data series. Year + 12 calendar-month rows; the missing-value sentinel varies per file and is read from the lone numeric line after the data.
• knmi-climexp (climexp dialect) — KNMI Climate Explorer <id>.dat monthly grids. Year + 12 months (a trailing annual-mean column is dropped when present); sentinel -999.9.

Notes

• One canonical source per index. Several of these indices (NAO, SOI, AMO, …) are published by both sources with slightly different definitions; the catalogue picks one canonical source per id. A per-request source= override is a future addition.

• Not shipped (yet). The bi-monthly MEI.v2 series is excluded from this set because its columns are 2-month seasons (DJ, JF, …), not calendar months, so it does not fit the calendar-monthly schema. The YYYYMMDD value climexp long form (e.g. PDO on climexp) is likewise a follow-on; PDO here comes from NOAA PSL.