Key Laboratory of Meteorological Disaster, Ministry of Education, Joint International Research Laboratory of Climate and Environment Change (ILCEC), Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Nanjing University of Information Science & Technology, Nanjing 210044, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519080, China; Nansen-Zhu International Research Centre, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China.
Key Laboratory of Meteorological Disaster, Ministry of Education, Joint International Research Laboratory of Climate and Environment Change (ILCEC), Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Nanjing University of Information Science & Technology, Nanjing 210044, China.
Sci Bull (Beijing). 2023 Mar 15;68(5):528-535. doi: 10.1016/j.scib.2023.02.009. Epub 2023 Feb 9.
The "Arctic warming-Eurasia cooling" trend has significantly affected the changes of weather patterns and climate extremes at lower latitudes and has attached huge attentions. However, this winter trend weakened from 2012 to 2021. In the same time period, subseasonal reversals between the warm Arctic-cold Eurasia (WACE) and cold Arctic-warm Eurasia (CAWE) patterns became more frequent and the subseasonal intensity of the WACE/CAWE pattern was still comparable with that from 1996 to 2011. This study highlighted the co-occurrence of this subseasonal variability and trend changes in the WACE/CAWE pattern based on long-term reanalysis datasets and Coupled Model Intercomparison Project Phase 6 simulations. The preceding sea surface temperature anomalies in the tropical Atlantic and Indian oceans had significant primary impacts on the WACE/CAWE pattern in early and late winter, respectively, which were confirmed by numerical experiments based on the Community Atmosphere Model and Atmospheric Model Intercomparison Project. Their coordination worked to effectively modulate the subseasonal phase reversal between the WACE and CAWE patterns just like what happened in the winters of 2020 and 2021. Findings of the present study imply that subseasonal changes need to be considered in the prediction of climate extremes at mid- to low latitudes.
“北极暖、欧亚冷”趋势显著影响低纬天气气候极端变化，受到广泛关注。然而，该趋势在 2012 年至 2021 年期间减弱。同期，北极暖、欧亚冷（WACE）与北极冷、欧亚暖（CAWE）两种亚季节型的反转更为频繁，且 WACE/CAWE 型的亚季节强度仍与 1996 年至 2011 年相当。本研究基于长期再分析资料和第六次耦合模式比较计划模拟结果，突出强调了这种亚季节变率与 WACE/CAWE 型趋势变化的同时出现。热带大西洋和印度洋海表温度异常的前期信号对冬季早期和晚期的 WACE/CAWE 型有显著的主要影响，这一结论得到了基于大气环流模式和大气模型比较计划的数值实验的证实。它们的协调作用有效调节了 WACE 和 CAWE 型之间的亚季节位相反转，就像 2020 年和 2021 年冬季发生的情况一样。本研究的结果表明，在预测中低纬气候极端事件时需要考虑亚季节变化。
