Two new sea surface temperature anomalies indices for capturing the eastern and central equatorial Pacific type El Niño‐Southern Oscillation events during boreal summer

Using monthly mean data from the Hadley Center and the National Centers for Environmental Prediction‐National Center for Atmospheric Research (NCEP‐NCAR) reanalysis, we have constructed two new indices I CP and I EP of boreal summer sea surface temperature anomalies (SSTA) in equatorial Pacific for period of 1963–2016 by employing methods including the six‐order polynomial fitting and pattern correlations. The new indices I CP and I EP are almost independent of each other. Using these two indices, we are able to successfully capture the main features of central Pacific (CP) and eastern Pacific (EP) type SSTA variations in tropical Pacific in both spatial and temporal. The EP‐type SSTA events vary on inter‐annual timescales whereas CP‐type events vary on both inter‐annual and…