해양-대기 접합모형에서 ENSO 크기의 장주기 변동성의 원인

Abstract

The dominant El Nino and Southern Oscillation period increased from 2-3 years during 1960-1975 to 4-6 years after the late 190s. The amplitude of ENSO also tends to increase. However, the causes of ENSO amplitude modulation on decadal timescales are currently unknown. Recently, Moon et al (2004) suggested that changes in ENSO statistics is due to redistribution of baroclinic energy by change of vertical stratification in the equatorial Pacific, but they did not provide why the vertical stratification changes on decadal timescales. In this study we use the results from simulation to investigate the change in the equatorial subsurface structure and its impact on the ENSO decadal modulation.