Sea level anomalies in the southeastern tropical Indian Ocean as a potential predictor of La Niña beyond one-year lead

Frontiers in Marine Science

Marine Science

Xia Zhao¹  Jing Wang¹  Dongliang Yuan² 

[1] Key Laboratory of Ocean Circulation and Waves, Institute of Oceanology, and Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, China;Qingdao National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China;University of Chinese Academy of Sciences, Beijing, China;Key Laboratory of Ocean Circulation and Waves, Institute of Oceanology, and Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, China;Qingdao National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China;University of Chinese Academy of Sciences, Beijing, China;Key Laboratory of Marine Science and Numerical Modeling, First Institute of Oceanography, Ministry of Natural Resources, Qingdao, China;Shandong Key Laboratory of Marine Science and Numerical Modeling, Qingdao, China;

关键词: precursor of La Niña;    sea level anomalies;    southeastern tropical Indian;    Indian Ocean Dipole;    oceanic channel;    upwelling;    Ocean Kelvin waves;   

DOI  :  10.3389/fmars.2023.1141961

 received in 2023-01-11, accepted in 2023-02-28,  发布年份 2023

来源: Frontiers

【 摘 要 】

Most climate forecast agencies failed to make successful predictions of the strong 2020/2021 La Niña event before May 2020. The western equatorial Pacific warm water volume (WWV) before the 2020 spring failed to predict this La Niña event because of the near neutral state of the equatorial Pacific Ocean in the year before. A strong Indian Ocean Dipole (IOD) event took place in the fall of 2019, which is used as a precursor for the La Niña prediction in this study. We used observational data to construct the precursory relationship between negative sea level anomalies (SLA) in the southeastern tropical Indian Ocean (SETIO) in boreal fall and negative Niño 3.4 sea surface temperature anomalies index one year later. The application of the above relation to the prediction of the 2020/2021 La Niña was a great success. The dynamics behind are the Indo-Pacific “oceanic channel” connection via the Indian Ocean Kelvin wave propagation through the Indonesian seas, with the atmospheric bridge playing a secondary role. The high predictability of La Niña across the spring barrier if a positive IOD should occur in the previous year suggests that the negative SETIO SLA in fall is a much better and longer predictor for this type of La Niña prediction than the WWV. In comparison, positive SETIO SLA lead either El Niño or La Niña by one year, suggesting uncertainty of El Niño predictions.

【 授权许可】

Unknown   
Copyright © 2023 Zhao, Yuan and Wang