Liang X San, Xu Fen, Rong Yineng, Zhang Renhe, Tang Xu, Zhang Feng
Department of Atmospheric and Oceanic Sciences, Institute of Atmospheric Sciences, Fudan University, No. 2005 Songhu Rd, Yangpu District, Shanghai, 200438, China.
Nanjing Center for Ocean-Atmosphere Dynamical Studies, Nanjing Institute of Meteorology, Nanjing, 210044, China.
Sci Rep. 2021 Sep 9;11(1):17860. doi: 10.1038/s41598-021-97111-y.
The 2014-2015 "Monster"/"Super" El Niño failed to be predicted one year earlier due to the growing importance of a new type of El Niño, El Niño Modoki, which reportedly has much lower forecast skill with the classical models. In this study, we show that, so far as of today, this new El Niño actually can be mostly predicted at a lead time of more than 10 years. This is achieved through tracing the predictability source with an information flow-based causality analysis, which has been rigorously established from first principles during the past 16 years (e.g., Liang in Phys Rev E 94:052201, 2016). We show that the information flowing from the solar activity 45 years ago to the sea surface temperature results in a causal structure resembling the El Niño Modoki mode. Based on this, a multidimensional system is constructed out of the sunspot number series with time delays of 22-50 years. The first 25 principal components are then taken as the predictors to fulfill the prediction, which through causal AI based on the Liang-Kleeman information flow reproduces rather accurately the events thus far 12 years in advance.
2014 - 2015年的“超级”厄尔尼诺事件由于一种新型厄尔尼诺——Modoki厄尔尼诺的重要性日益增加，未能提前一年被预测出来，据报道，经典模型对其预测能力要低得多。在本研究中，我们表明，截至目前，这种新型厄尔尼诺实际上大多可以在提前10多年的时间被预测。这是通过基于信息流的因果分析追踪可预测性来源实现的，该分析在过去16年中已从第一原理严格建立起来（例如，Liang在《物理评论E》94:052201, 2016中所述）。我们表明，45年前从太阳活动流向海面温度的信息导致了一种类似于Modoki厄尔尼诺模式的因果结构。基于此，利用延迟22 - 50年的太阳黑子数序列构建了一个多维系统。然后将前25个主成分作为预测因子来进行预测，通过基于Liang - Kleeman信息流的因果人工智能，该预测提前12年相当准确地再现了迄今为止的事件。
