Reconstructed SST-NINO3.4 anomalies for the years 850 to 1981

This data set gives values of reconstructed SST-NINO3.4 anomalies for the years 850 to 1981. SST-NINO3.4 is a key ENSO (El Niño Southern Oscillation) index, defined as the spatial average of Sea Surface Temperature (SST) over the NINO3.4 spatial box (170°W-120°W, 5°S-5°N). The reconstructed SST-NINO3.4 anomalies are obtained from a new multiproxy reconstruction based on 45 proxy records obtained from the Past Global Changes 2k database (PAGES 2k Consortium, 2017, 2019) and a so-called Random Forest method. The reconstructed anomalies are relative to the 1870-2014 averaged SST-NINO3.4 obtained from the HadISST product (Rayner et al. 2003). Units are degrees Celsius