Description:
Top: The red line represents the Niño 3.4 standardized sea surface temperature anomaly, and the blue line represents the standardized 925 hPa zonal wind anomaly averaged over the eastern and central equatorial Pacific Ocean (5°S-5°N and 150°E-90°W) for the last five years. A three-month running average is applied to both time series.
Bottom: The bottom plot is the same as the top, but for the past 25 years.
NCEP is
an acronym for the US National Centers for Environmental Prediction.