近日，中国科学院大气物理研究所Yao Meng的课题组取得一项新突破。他们研究出南海海洋中尺度涡旋轨迹的可预报极限。该项研究成果发表在2024年2月2日出版的《大气科学进展》上。

研究结果表明，南海气旋性涡旋(CEs)和反气旋涡旋(AEs)的海洋中尺度涡旋轨迹的可预报极限分别为39天和44天。可预测性极限与海洋中尺度涡旋的性质和季节有关。寿命长、振幅大、半径小的海洋中尺度涡旋往往具有较高的可预测性极限。反气旋涡旋 (气旋性涡旋)轨迹的可预报极限在秋季(冬季)最高，为52 (53)天，在春季(夏季)最低，为40 (30)天。

海洋中尺度涡旋轨迹的可预测极限的空间分布也随季节的变化而变化，研究发现，高可预测极限的区域往往与周期性的预兆重叠。此外，气旋性涡旋和反气旋涡旋的周期性海洋中尺度涡旋轨迹的可预测性极限都在49天左右，比平均值高5-10天。通常，在南海中，具有高可预测性极限值的先兆往往显示出更长的和更平滑的轨迹，并且经常沿着南海的北坡移动。

据研究人员介绍，本文采用非线性局地Lyapunov指数(NLLE)方法，使用年度和季度平均值的三个涡流数据集，来定量估计海洋中尺度涡旋(OME)轨迹的可预报极限。

附：英文原文

Title: The Predictability Limit of Oceanic Mesoscale Eddy Tracks in the South China Sea

Author: Hailong LIU, Pingxiang Chu, Yao Meng, Mengrong DING, Pengfei LIN, Ruiqiang Ding, Pengfei Wang, Weipeng ZHENG

Issue&Volume: 2024-02-02

Abstract: This study uses the nonlinear local Lyapunov exponent (NLLE) method to quantitatively estimate the predictability limit of oceanic mesoscale eddy (OME) tracks using three eddy datasets for both annual and seasonal mean. The results show that the predictability limit of OME tracks is about 39 days for cyclonic eddies (CEs) and 44 days for anticyclonic eddies (AEs) in the South China Sea (SCS). The predictability limit is related to the OME properties and seasons. The long-lived, large-amplitude, and -radius OMEs tend to have a higher predictability limit. The predictability limit of AE (CE) tracks is highest in autumn (winter) with 52 (53) days and lowest in spring (summer) with 40 (30) days. The spatial distribution of the predictability limit of OME tracks also varies with seasons, and we found that the higher predictability limits area often overlaps with periodic OMEs. Additionally, the predictability limit of periodic OME tracks is about 49 days for both CEs and AEs, which is 5-10 days higher than the mean values. Usually, in the SCS, OMEs with high predictability limit values often show extender and smoother trajectories and often move along the northern slope of SCS.

DOI: 10.1007/s00376-024-3250-7

Source: http://www.iapjournals.ac.cn/aas/en/article/doi/10.1007/s00376-024-3250-7viewType=HTML