Wu Qigang, Ma Yejian, Hu Aixue, Rosenbloom Nan, Zhang Lei, Liu Heng, Liu Shizuo, Yang Luping, Yang Chang
Department of Atmospheric and Oceanic Sciences, Fudan University, Shanghai, China.
Key Laboratory of Polar Atmosphere-Ocean-Ice System for Weather and Climate, Ministry of Education, Fudan University, Shanghai, China.
Nat Commun. 2025 Apr 10;16(1):3386. doi: 10.1038/s41467-025-58788-1.
Total sea ice extent (SIE) across the Southern Ocean increased from 1979-2014, but declined rapidly after 2016. Significant sea ice decline has emerged since the peak of SIE in 2014, coincident with Pacific sub-decadal sea surface temperature (SST) trends resembling a strong La Niña-like cold condition and the negative phase of the interdecadal Pacific oscillation (IPO). Previous studies suggest that the warm subsurface Southern Ocean was an important driver of the low sea ice in spring 2016 and the sustained low sea ice state since. Here we show that the observed atmospheric circulation changes near Antarctica during the period from June 2013-May 2023 are conducive to increasing surface temperature via warm advection from north and reducing Antarctic SIE, involving a deepening of the Amundsen Sea Low and anomalous high pressures over the Weddell Sea and West Pacific sectors. Through coupled pacemaker experiments, we demonstrate that Pacific sub-decadal SST trends have dominantly driven these atmospheric circulation changes through tropical-polar teleconnections and also induced significant Southern Ocean subsurface warming in the recent decade. The consequent decreasing SIE has enhanced the Southern Ocean subsurface warming effect and significantly contributed to the rapid Antarctic SIE decline.
1979年至2014年期间，南大洋的总海冰范围（SIE）有所增加，但在2016年之后迅速下降。自2014年SIE达到峰值以来，海冰出现了显著下降，这与太平洋年代际海表温度（SST）趋势类似强烈的拉尼娜式寒冷状况以及年代际太平洋振荡（IPO）的负相位相吻合。先前的研究表明，南大洋温暖的次表层是2016年春季海冰偏低以及此后持续低海冰状态的重要驱动因素。在此我们表明，2013年6月至2023年5月期间在南极洲附近观测到的大气环流变化有利于通过来自北方的暖平流增加地表温度并减少南极SIE，这涉及阿蒙森海低压的加深以及威德尔海和西太平洋区域的异常高压。通过耦合起搏器实验，我们证明太平洋年代际SST趋势主要通过热带-极地遥相关驱动了这些大气环流变化，并且在最近十年还导致了南大洋次表层显著变暖。由此导致的SIE下降增强了南大洋次表层变暖效应，并显著促成了南极SIE的快速下降。
