AN ENSO-LIKE OSCILLATION SYSTEM

This paper presents the following data based hypothesis on the mechanism of the El Nio Southern Oscillation (ENSO) cycle: during the warm phase of ENSO, there are westerly wind anomalies over the equatorial west central Pacific and the sea surface temperature (SST) in the equatorial east central Pacific is higher. The latter can strengthen Hadley circulation, and the west component of the Hadley circulation anomaly may cause southerly monsoon circulation. When the monsoon is a southerly anomaly, SST in the South China Sea (SCS) becomes higher. When the SCS gets warmer, the atmospheric convection will move to it, and then easterly anomaly wind will occur over the western Pacific. A cycle is completed. This hypothesis was used to construct an analogical oscillator model that produces ENSO like oscillations. The negative feedback mechanism of the hypothesis is SST anomaly in the SCS. This negative feedback mechanism is quite different from others proposed before, is not within the Pacific and does not depend on ocean waves and their boundary reflection.

This paper presents the following data-based hypothesis on the mechanism of the EI Ni?o-Southern Oscillation (ENSO) cycle: during the warm phase of ENSO, there are weterly wind anomalies over the equatorial west-central Pacific and the sea surface temperature (SST) in the equatorial east-central Pacific is higher. The latter can strengthen Hadley circulation, and the west component of the Hadley circulation anomaly may cause southerly monsoon circulation. When the monsoon is a southerly anomaly, SST in the South China Sea (SCS) becomes higher. When the SCS gets warmer, the atmospheric convection will move to it, and then easterly anomaly wind will occur over the western Pacific. A cycle is completed. This hypothesis was used to construct an analogical oscillator model that produces ENSO-like oscillations. The negative feedback mechanism of the hypothesis is SST anomaly in the SCS. This negative feedback mechanism is quite different from others proposed before, is not within the Pacific and does not depend on ocean waves and their boundary reflection.