Variation Characteristics of Sea Surface Energy Balance over the Tropical Pacific and Its Relationship with Two Types of El Niño-Southern Oscillation (ENSO) Events

Based on the atmospheric data from NCEP, sea surface temperature (SST) data from the Hadley Center, sea surface heat fluxes and related physical data from OAFlux, and cloud data from NCAR/NOAA, the characteristics of heat fluxes were analyzed over the tropical Pacific and then the different characteristics and influential factors of turbulent heat fluxes between two types of ENSO events were investigated. The main conclusions are as follows: The maximum amplitude of the net heat flux variation is found over the equatorial Pacific, which is mainly caused by variations of the latent heat flux and shortwave radiation flux. Using the SST indexes associated with two types of ENSO events, partial regressions are applied to investigate the influence of SST on the heat fluxes in every evolution stage. Negative anomalies of the net heat flux can be captured over the equatorial Pacific during the two types of ENSO events. However, the range and the amplitude of the anomalies are much broader and stronger over the equatorial Pacific under the partial regression of Niño3 than those of El Niño Modoki index (EMI). Besides, the SST of the maturing periods has the greatest impact on the contemporaneous turbulence heat fluxes over the equatorial eastern Pacific in both events.