전지구 기후 모델에 따른 ENSO의 성격 변화

Abstract

There is a significant CGCM dependence on future changes to El Nino and Southern Oscillation (ENSO) properties. Some CGCMs show an enhanced ENSO amplitude and some show a reduced ENSO amplitude and some show little change at all. The origin of these differences is unknown and remains a difficult problem; so far there is no consensus on the mechanisms which explain changes in ENSO statistics under global warming. In spite of such diverse results, it is useful to examine the reason why the CGCMs show different changes in ENSO statistics to climate change projections. Some climate system models are chosen for an analysis of ENSO amplitude changes under global warming. The results suggest that the understanding of changes in ENSO statistics among various climate change projections is highly dependent on whether the model ENSO is in the linear or nonlinear regime. In addition, it is found that the upper ocean structure simulated in the CGCMs is a key parameter of the sensitivity of ENSO statistics to global warming.