Precursory Signals of Extensive and Persistent Extreme Cold Events in China  

作　　者：PENG Jing-Bei BUEH Cholaw 

机构地区：[1]The International Center for Climate and Environment Sciences, Institute of Atmospheric Physics, Chinese Academy of Sciences [2]The State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences [3]The International Center for Climate and Environment Sciences, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China [4]The State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmos-pheric Physics, Chinese Academy of Sciences, Beijing 100029, China

出　　处：《Atmospheric and Oceanic Science Letters》2012年第3期252-257,共6页大气和海洋科学快报（英文版）

基　　金：supported by the National Key Technologies R&D Program of China (Grant No. 2009BAC51B02)

摘　　要：The distinct precursory signals of countrywide extensive and persistent extreme cold events (CECs) were investigated and contrasted with those of countrywide cold wave events (CCWs). It is shown that most CECs were accompanied by a CCW in the initial stages. From the comparison between the CECs and the CCWs that were independent of any CEC, it is found that a south- west-northeast-oriented tilted ridge at 500 hPa was present around the Europe-Barents Sea regions approximately 10 days prior to the start of the CEC. Consistent with this feature, a high sea level pressure and strong cold air accumulation occurred over a broad extent of northern Eurasia one week prior to the start of the CEC. The tilted ridge and the strong cold air accumulation were the precursory signals that were absent for the CCW, and they provide important clues for the early prediction of whether a CCW event might evolve into a CEC.The distinct precursory signals of countrywide extensive and persistent extreme cold events （CECs） were investigated and contrasted with those of countrywide cold wave events （CCWs）. It is shown that most CECs were accompanied by a CCW in the initial stages. From the comparison between the CECs and the CCWs that were independent of any CEC, it is found that a south- west-northeast-oriented tilted ridge at 500 hPa was present around the Europe-Barents Sea regions approximately 10 days prior to the start of the CEC. Consistent with this feature, a high sea level pressure and strong cold air accumulation occurred over a broad extent of northern Eurasia one week prior to the start of the CEC. The tilted ridge and the strong cold air accumulation were the precursory signals that were absent for the CCW, and they provide important clues for the early prediction of whether a CCW event might evolve into a CEC.

关 键 词：precursory signal extensive and persistent extreme cold event cold wave the tilted ridge 

分 类 号：P315.7[天文地球—地震学] P732[天文地球—固体地球物理学]