Intensity of the Trough over the Bay of Bengal and Its Impact on the Southern China Precipitation in Winter  

作　　者：ZONG Hai-Feng BUEH Cholaw WEI Jie CHEN Lie-Ting 

机构地区：[1]The International Center for Climate and Environment Sciences （ICCES）, Institute of Atmospheric Physics, Chinese Academy of Sciences [2]State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences

出　　处：《Atmospheric and Oceanic Science Letters》2012年第3期246-251,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 Nos.2009BAC51B02 and 2007BAC29B03);the China Meteorological Administration Special Public Welfare Research Fund (Grant No.GYHY200906014);the Natural Science Foundation of China(Grant No. 40975033)

摘　　要：In this study, the intensity of the trough over the Bay of Bengal (BBT) and its association with the southern China precipitation, the Madden-Julian Oscillation (MJO) and the Rossby wave propagation along the African-Asian subtropical Jet stream (AASJ) are investigated on the intraseasonal time scale. The results show that the intensity of the BBT affects the southern China precipitation more directly and to a greater degree than the MJO. The peak amplitude of the BBT tended to occur in phase-3 of the MJO. The strong BBT was substantially modulated by the Rossby wave propagation along the AASJ, which was triggered by the anomalous upstream circulation similar to the pattern of the North Atlantic Oscillation (NAO). Therefore, from the perspective of medium- and extended-range weather forecasts, the NAO- like pattern may be regarded as a precursory signal for the strong BBT and thus the southern China precipitation.In this study, the intensity of the trough over the Bay of Bengal （BBT） and its association with the southern China precipitation, the Madden-Julian Oscillation （MJO） and the Rossby wave propagation along the African-Asian subtropical Jet stream （AASJ） are investigated on the intraseasonal time scale. The results show that the intensity of the BBT affects the southern China precipitation more directly and to a greater degree than the MJO. The peak amplitude of the BBT tended to occur in phase-3 of the MJO. The strong BBT was substantially modulated by the Rossby wave propagation along the AASJ, which was triggered by the anomalous upstream circulation similar to the pattern of the North Atlantic Oscillation （NAO）. Therefore, from the perspective of medium- and extended-range weather forecasts, the NAO- like pattern may be regarded as a precursory signal for the strong BBT and thus the southern China precipitation.

关 键 词：the trough over the Bay of Bengal MJO PRECIPITATION NAO Rossby wave 

分 类 号：P458.121[天文地球—大气科学及气象学] P532