2015年超级厄尔尼诺事件的成功预报

Successful Prediction for the Super El Niño Event in 2015

        郑飞(中国科学院大气物理研究所 北京 100029)
        朱江(中国科学院大气物理研究所 北京 100029)
        张荣华(中国科学院海洋研究所 青岛 266071)
        彭京备(中国科学院大气物理研究所 北京 100029)

         超级厄尔尼诺;厄尔尼诺预报系统;气候预测;防灾减灾

        super El Niño;El Niño forecasting system;climate prediction;disaster prevention and mitigation

        2015年初,热带太平洋明显出现了厄尔尼诺事件爆发的一些前期物理信号,这些大气和海洋中呈现的前兆信号与上次爆发超级厄尔尼诺事件的1997年同期非常相似。伴随着赤道西风的增强和暖水的东传,赤道中东太平洋次表层(即洋面以下)暖水不断积聚,赤道东太平洋海温增温也更加显著。到10月份以后,赤道中东太平洋海温已经比常年同期偏高2.0℃-3.0℃以上,发展成为21世纪最强的一次厄尔尼诺事件。相比国际上众多厄尔尼诺模型提前6-9个月未能给出正确预报的现状,在中科院战略先导专项海洋专项的支持下持续发展的厄尔尼诺预报系统(中科院大气所集合预报版本:IAP Leefs_CDA),则提前9个月以上对该超级厄尔尼诺事件的爆发、发展和强度给出了成功的预报,为我国的气候预测和防灾减灾提供了有力的支撑。同时,厄尔尼诺预报系统的另一版本(中科院海洋所确定性预报版本:IOCAS ICM)也首次在美国哥伦比亚大学网站上提供厄尔尼诺实时预报结果。

        In early 2015, the tropical Pacific Ocean appears to be primed for a potentially significant El Niño event, and some similarities exist between the oceanic and atmospheric states compared to the observations shortly before the onset of the 1997 Super El Niño event. Associated with the enhanced westerly winds and the eastbound migration of the warm water over the equatorial Pacific, subsurface warm water tended to accumulate over the eastern equatorial Pacific, and the warming of ocean temperature in the eastern basin was getting more obvious. After October 2015, the sea surface temperature over the eastern equatorial Pacific was 2.0-3.0℃ warmer than the normal condition, developing to the strongest El Niño event in 21^st century. Different from the status that most El Niño model from operational centers over the world didnot predict the event 6-9 months ahead, the developed El Niño forecasting system(i.e., the ensemble prediction version developed in the Institute of Atmospheric Physics), was supported by the"Western Pacific Ocean System:Structure, Dynamics and Consequences"Project of the Chinese Academy of Sciences(CAS), successfully predicted the onset, development, and amplitude of this El Niño event 9 months in advance. This successful forecasting result further significantly supported the climate prediction and the disaster prevention and mitigation in China. At the same time, the other version of the El Niño forecasting system(i.e., a deterministic system developed in the Institute of Oceanology, CAS), for the first time, started to release the realistic El Niño forecasting result at the website of the University of Columbia in US.