石晨. 2020. 东北亚和北半球冬季高空切断冷涡与中国极端低温事件的联系[J]. 气象学报, (0):-, doi:10.11676/qxxb2020.049
东北亚和北半球冬季高空切断冷涡与中国极端低温事件的联系
The relationship between winter cut-off cold vortex in the Northeast Asia and Northern Hemisphere and the extreme low temperature events in China
投稿时间:2019-08-22  修订日期:2020-02-17
DOI:10.11676/qxxb2020.049
中文关键词:  北半球冷涡,东北亚冷涡,极端低温,信息流,因果关系
英文关键词:Cold vortex in Northern Hemisphere, Cold vortex in Northeast Asia, Extreme low temperature, Information flow, Causality
基金项目:国家自然科学基金重大项目课题(41790471)、国家自然科学基金项目(41875119、41630424、41975101)、中国气象局省级气象科研所科技创新发展项目(SSFZ201806)
作者单位E-mail
石晨 吉林省气象科学研究所 746105496@qq.com 
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中文摘要:
      [资料和方法] 利用NCEP/NCAR再分析资料和CPC冬季逐日温度资料,通过机器自动识别和目视相结合的方法,研究了北半球冬季500hPa冷涡分布特征,并基于线性相关和信息流因果论方法,[目的] 揭示了东北亚冷涡活动与北半球其它活动区冷涡以及中国冬季极端低温事件的联系。[结果] 根据冷涡活动天数随经度的变化,划分了四个活动频繁区,发现北半球冬季冷涡活动频率从大到小分别为大西洋-欧洲区(37.7%)、北太平洋区(22.35%)、东北亚区(20.95%)和北美-格陵兰区(13.77%)。北美-格陵兰区冷涡平均中心强度最强(493gpm),大西洋-欧洲区最弱(514gpm)。东北亚区冷涡活动具有相对独立性,唯有1月北美-格陵兰区冷涡活动天数是2月东北亚冷涡动天数年际变化的不稳定影响源。冷涡强年的动力学特征分析表明,东北亚区和北美-格陵兰区冷涡与NAO正位相密切相联,北太平洋区冷涡则与NPO正位相相联系,大西洋-欧洲区冷涡则对应于NAO和NPO负位相。东北亚冷涡与中国极端低温联系密切,1979-2017年冬季中国发生50次极端冷事件,其中有40次与东北亚冷涡活动有关。
英文摘要:
      Using NCEP/NCAR reanalysis data and CPC daily temperature data, the distribution characteristics of 500hPa cold vortex in Northern Hemisphere winter are studied by automatic machine identification and visual method. Based on linear correlation and information flow causality theory, the relationship between cold vortex in Northeast Asia and other active regions in Northern Hemisphere and the extreme cold events in China is investigated. According to the variations of cold vortex cumulative days along longitude, four active subregions were divided. It was found that the frequency of cold vortex activity in the Northern Hemisphere winter ranged from 37.7% in Atlantic-European region, 22.35% in North Pacific region, 20.95% in Northeast Asia region and 13.77% in North America-Greenland region. The averaged central intensity of cold vortex in North America-Greenland region is the strongest (493gpm), while that in Atlantic-European region is the weakest (514gpm). The activities of cold vortex in Northeast Asia are relatively independent. Only cold vortex days of North America-Greenland in January are the unstable sources of the interannual variations of that in Northeast Asia in February. The analysis of the dynamic characteristics of cold vortex for strong years shows that the cold vortex in Northeast Asia and North America-Greenland is closely related to the positive phase of NAO, the cold vortex in the North Pacific is closely related to the positive phase of NPO, while the cold vortex in the Atlantic-European region corresponds to the negative phase of NAO and NPO. The cold vortex in Northeast Asia is closely related to extreme low temperature events in China. There were 50 extreme cold events in winter from 1979 to 2017 in China, 40 of which were related to the activities of cold vortex in Northeast Asia.
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