School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, China.
Department of Atmospheric, Oceanic, and Earth Sciences and Center for Ocean-Land-Atmosphere Studies, George Mason University, Fairfax, Virginia, USA.
Sci Rep. 2018 Oct 18;8(1):15352. doi: 10.1038/s41598-018-33436-5.
El Niño-Southern Oscillation (ENSO) exerts tremendous influences on the global climate. Through dynamic lifting and thermal forcing, the Maritime Continent (MC) plays an important role in affecting global atmospheric circulation. In spite of the extensive studies on ENSO mechanisms, the influence of MC on the characteristics of ENSO life cycle remains unclear. Our coupled model experiments reveal that the absence of the MC land contributes to a strong ENSO asymmetry and a weakened nonlinear atmospheric response to the combined seasonal and interannual SST variations (i.e. the combination mode) that prolongs the warm events, resulting in a reduction of ENSO frequency. On the other hand, our experiments suggest that the global climate model applied (NCAR CESM) overestimates the MC topographic uplifting effect on ENSO simulation. Overall, this study provides a new physical insight into the nature of the MC influence on ENSO evolution.
厄尔尼诺-南方涛动(ENSO)对全球气候产生了巨大影响。通过动力抬升和热力强迫,海洋大陆(MC)在影响全球大气环流方面发挥着重要作用。尽管对 ENSO 机制进行了广泛的研究,但 MC 对 ENSO 生命周期特征的影响仍不清楚。我们的耦合模型实验表明,MC 陆地的缺失导致 ENSO 不对称性增强,以及非线性大气对季节和年际海表温度变化(即组合模式)的响应减弱,这延长了暖事件的持续时间,从而降低了 ENSO 的频率。另一方面,我们的实验表明,所应用的全球气候模式(NCAR CESM)高估了 MC 地形抬升对 ENSO 模拟的影响。总的来说,本研究为 MC 对 ENSO 演化影响的本质提供了新的物理见解。