The figures at the top show the annual and monthly mean sea surface temperature (SST) in the El Niño Southern Oscilation 4 (ENSO 4). The lower plot is the SST time series in the region from January 1985 to the present, with one observation every approximately two days.
The upper figures are updated once a year. The lower figure is updated once a month to include the most recent data. The vertical bars are one standard deviation.
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