Data for: ENSO-conditioned evolution of global mean surface temperature

Observed and NMME forecast Nino-3.4 SST and global mean surface temperature, 1979–2026 The observations file (obs_n34_GMSTa_185001-202605.nc) provides monthly Nino-3.4 sea surface temperature (ERSSTv5, absolute, from January 1979) and global mean surface temperature anomaly (NOAA GlobalTempv6.1.0, 1991–2020 reference) for January 1850–May 2026. The global mean temperature record extends back to January 1850 so that the 1850–1900 preindustrial baseline can be computed directly from the file. The NMME file (nmme_n34a_GMSTa_199106-202606.nc) provides Nino-3.4 SST anomaly and global mean surface temperature anomaly from seven NMME models (June initializations, 1991–2026, leads 0.5–11.5 months): per-model ensemble means (n34a, GMSTa), individual ensemble members (ssta, trefa), observed Nino-3.4 on the same initialization/lead grid (obs_n34), and per-model ensemble size and forecast length (Mmax, Lmax). The relative Nino-3.4 file (Rnino34.ascii.txt) is an unmodified copy of the NOAA CPC monthly relative Nino-3.4 (RONI) index, December 1949–March 2026, retrieved 2026-04-03 from https://www.cpc.ncep.noaa.gov/data/indices/Rnino34.ascii.txt. Version 2 extends the observations file (previously June 1979–May 2026), adds the member-level NMME fields, observed Nino-3.4, and per-model metadata, and adds the RONI index file, so that all figures and tables of the associated manuscript are reproducible from this record.