Dynamic Seasonal Transition from Winter to Summer in the Northern Hemisphere Stratosphere  

作　　者：ZHANG Yu-Li LIU Yi LIU Chuan-Xi 

机构地区：[1]University of Chinese Academy of Sciences [2]Key Laboratory of Middle Atmosphere and Global Environmental Observation (LAGEO),Institute of Atmospheric Physics,Chinese Academy of Sciences

出　　处：《Atmospheric and Oceanic Science Letters》2014年第3期180-185,共6页大气和海洋科学快报（英文版）

基　　金：funded by the National Basic Research Program of China (Grant No.2010CB428604);the National Natural Science Foundation of China (Grant No.41105025);the Dragon 3 Programme (Grant No.10577)

摘　　要：This study applied the modified spatial similarity coefficient method to define the seasonal transition(ST) from winter to summer in the extratropical stratosphere of the Northern Hemisphere.The features of the ST were examined using European Centre for Medium-Range Weather Forecasts(ECMWF) Interim reanalysis data;and the results showed that the time and duration of the ST,which is affected by the activity of planetary waves(PW) in the stratosphere,largely depended on the geophysical locations.This study also investigated the interannual variability of the ST and its relationship with stratospheric sudden warming(SSW) and the quasi-biennial oscillation(QBO).It was shown that the late-onset SSW events(after 22 January) are close to the start of the ST.An easterly(westerly) QBO hastens(delays) the onset of the ST in high and low latitudes,whereas it delays(hastens) the ST in midlatitudes.The duration of the ST is significantly affected by the QBO.The influence of SSW and the QBO have different significance in different latitudes,so they are both important and irreplaceable factors.This study applied the modified spatial simi- larity coefficient method to define the seasonal transition （ST） from winter to summer in the extratropical strato- sphere of the Northern Hemisphere. The features of the ST were examined using European Centre for Medium- Range Weather Forecasts （ECMWF） Interim reanalysis data; and the results showed that the time and duration of the ST, which is affected by the activity of planetary waves （PW） in the stratosphere, largely depended on the geophysical locations. This study also investigated the interannual variability of the ST and its relationship with stratospheric sudden warming （SSW） and the qua- si-biennial oscillation （QBO）. It was shown that the late-onset SSW events （after 22 January） are close to the start of the ST. An easterly （westerly） QBO hastens （de- lays） the onset of the ST in high and low latitudes, whereas it delays （hastens） the ST in midlatitudes. The duration of the ST is significantly affected by the QBO. The influence of SSW and the QBO have different sig- nificance in different latitudes, so they are both important and irreplaceable factors.

关 键 词：SEASONAL transitionstratospherestratospheric SUDDEN warmingquasi-biennial oscillation 

分 类 号：P421.32[天文地球—大气科学及气象学] S510.93[农业科学—作物学]