影响中国寒潮年代际变化的主要大气环流模态  

Main modes affecting the interdecadal variations in cold waves in China

作　　者：曾彦博 李旭[1] 夏权 李艳[1] ZENG Yan-bo;LI Xu;XIA Quan;LI Yan(College of Atmospheric Sciences,Lanzhou University,Lanzhou 730000,China;Yellow River Basin Ecotope Integration of Industry and Education Research Institute,Lanzhou Resources&Environment Vocational and Technical University,Lanzhou 730021,China)

机构地区：[1]兰州大学大气科学学院,兰州730000 [2]兰州资源环境职业技术大学黄河流域生态环境产教融合研究院,兰州730021

出　　处：《兰州大学学报（自然科学版）》2024年第3期313-323,共11页Journal of Lanzhou University(Natural Sciences)

基　　金：甘肃省自然科学基金项目(21JR7RA772,21JR7RA497,21JR7RA495);兰州资源环境职业技术大学黄河流域生态环境产教融合研发基金(XHYF2023-02)。

摘　　要：利用1951-2020年中国寒潮事件集和ERA5,分析中国寒潮的特征和变化趋势,通过自组织映射神经网络方法研究影响中国寒潮的主要模态,使用混合单粒子拉格朗日综合轨迹模型追踪寒潮冷空气路径.结果表明,1951-2020年,中国全国性寒潮的累计发生天数呈显著下降趋势,特别是在80年代前后发生了年代际变化,80年代之前,影响寒潮的主要模态包括对应西北路径的贝湖低涡型和极涡东南延伸型、对应偏北路径的阻高极涡型、对应偏西路径的北极涛动负位相型和对应偏东路径的北大西洋涛动正位相型;80年代以后,寒潮的累积发生天数急剧减少,且入侵位置东移.主要模态变为对应西北路径的阻高极涡型、对应偏北路径的北极高压和阻塞高压打通型、对应偏西路径的北极涛动负位相型和对应偏东路径的西部极涡型,其中西北路径冷空气入侵位置东移,且占比减小;偏东路径的冷空气占比增大;新出现的北极高压和阻塞高压打通型模态对应的冷空气路径偏北,入侵距离偏短.北极高压和阻塞高压打通型可能对中国冬季天气气候产生影响,这种模态下在乌拉尔山地区有阻塞高压,同时期在新地岛至北地群岛一带存在北极高压,两者为同位相打通,高压脊为东北西南走向,使得西伯利亚高压的位置偏北、强度偏强、影响范围偏大,易于产生影响范围广、降温幅度大的北路或东路型寒潮,降温范围覆盖中国西北、华北以及华南等多个地区,降温中心强度可达到8~10℃.We analyzed the cold wave event dataset provided by the China Meteorological Administration for the period 1951-2020 and the ERA5,to come up with the characteristics and trends of nationwide cold waves in China.We used the self-organizing map neural network method to investigate the primary modes affecting cold waves in China and the hybrid single-particle Lagrangian integrated trajectory model to track the trajectories of cold air associated with cold waves.The results indicated a significant decreasing trend in the cumulative number of nationwide cold wave occurrences in China from 1951 to 2020,with particularly decadal variations around the 1980s.Before that,the primary modes influencing cold waves included the Baikal low vortex type and the southeastward-extending polar vortex type corresponding to the northwest path,the blocking high-polar vortex type corresponding to the northern path,the negative phase of the Arctic oscillation(AO) corresponding to a western path,and the positive phase of the North Atlantic oscillation corresponding to an eastern path.After the 1980s,the cumulative number of cold wave occurrences rapidly decreased,and the invasion locations shifted eastern.The main modes became the blocking high-polar vortex type corresponding to the northwestern path,the Arctic high and blocking high linkage type corresponding to the northern path,the negative phase of the AO corresponding to a western path,and the western polar vortex type corresponding to an eastern path.In this period,the invasion location of cold air associated with the northwestern path shifted eastward and its proportion decreased.The proportion of cold air associated with the eastern path increased.The newly emerged mode corresponding to the Arctic high and blocking high linkage featured a northern path,with a shorter invasion distance.Further research indicated that the Arctic high and blocking high linkage mode might have had an impact on winter weather and climate in China.In this mode,there was a blocking high over the Ural Mou

关 键 词：寒潮 北极高压 阻塞高压 自组织映射网络 

分 类 号：P434[天文地球—大气科学及气象学]