Southward Shift of Westerly Anomalies Around El Niño Decay Related to High‐Frequency Variabilities
Year: 2025
Type: article
Abstract: The southward shift of anomalous westerlies from the equator to the south off‐equatorial areas plays a curtail role in demising El Niño, and was attributed to seasonal changes in the large‐scale environments in previous studies. Given that the southward shift exhibits a distinct spectral peak at the sub‐seasonal timescale, we propose that it could also be caused by the seasonal meridional movement of high‐frequency variabilities in the western tropical Pacific, such as the tropical cyclones (TCs) and Madden Julian Oscillation (MJO). It is found that the TCs and MJOs contribute to approximately 39% and 20% of the southward shift from October in El Niño years to the following March, respectively, both of which are significant at the 95% confidence level. Our findings supplement dynamics regarding to El Niño decay, and imply the necessity of improving seasonal forecast of high‐frequency variabilities for a better prediction of El Niño.
Source: Geophysical Research Letters
DOI: 10.1029/2024gl113964
Authors: Jie Wang, Tao Lian, Xiang Han, Chunzai Wang, Dake Chen
Institutions: Shanghai Jiao Tong University, Ministry of Natural Resources, Second Institute of Oceanography, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), State Key Laboratory of Satellite Ocean Environment Dynamics, Zhejiang Ocean University, Zhejiang University, South China Sea Institute Of Oceanology
Language: English
Subfield: Global and Planetary Change
Field: Environmental Science
Domain: Physical Sciences
SDG: Climate action
Open Access status: gold
Estimated APC paid: $3,190
Awards: G1779619546, G5350418420, G7930464592
OpenAlex ID: W4410922210