The interdecadal trend and shift of dry/wet over the central part of North China and their relationship to the Pacific Decadal Oscillation (PDO)  

作　　者：MA ZhuGuo 

机构地区：[1]Key Laboratory of Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy ofSciences, Beijing 100029, China

出　　处：《Chinese Science Bulletin》2007年第15期2130-2139,共10页

基　　金：the National Basic Research Program of China (Grant No. 2006CB400504);the Innovation Project of Chinese Academy of Sciences (Grant No. KZCX3-SW-229);the National Natural Science Foundation of China (Grant No. 40375028)

摘　　要：Based on monthly precipitation and monthly mean surface air temperature (SAT),the dry/wet trends and shift of the central part of North China and their relationship to the Pacific Decadal Oscillation (PDO) from 1951 to 2005 have been analyzed through calculating surface wetness index (SWI). The results indicate that there was a prominent drying trend and an abrupt change in the analysis period. A per-sistent warming period with less precipitation from the mid and late 1970s to present was found,and a shift process exists from the wet to the dry in the central part of North China during 1951-2005. The transition is located in the mid to late 1970s,which should be related to the shift variation of large-scale climate background. The correlation analysis has brought about a finding of significant correlativity between PDO index (PDOI) and SAT,precipitation and SWI in this region. The correlation exhibits that the positive phase of PDOI (warm PDO phase) matches warming,less precipitation and the drought period,and the negative PDOI phase corresponds to low SAT,more precipitation and the wet period. The duration of various phases is more than 25 years. The decadal variation of sea surface temperature (SST) in the North Pacific Ocean is one of the possible causes in forming the decadal dry/wet trend and shift of the central part of North China.Based on monthly precipitation and monthly mean surface air temperature （SAT）, the dry/wet trends and shift of the central pert of North China and their relationship to the Pacific Decadal Oscillation （PDO） from 1951 to 2005 have been analyzed through calculating surface wetness index （SWl）. The results indicate that there was a prominent drying trend and an abrupt change in the analysis period. A persistent warming period with less precipitation from the mid and late 1970s to present was found, and a shift process exists from the wet to the dry in the central part of North China during 1951-2005. The transition is located in the mid to late 1970s, which should be related to the shift variation of large-scale climate background. The correlation analysis has brought about a finding of significant correlativity between PDO index （PDOI） and SAT, precipitation and SWl in this region. The correlation exhibits that the positive phase of PDOI （warm PDO phase） matches warming, less precipitation and the drought period, and the negative PDOI phase corresponds to low SAT, more precipitation and the wet period. The duration of various phases is more than 25 years. The decadal variation of sea surface temperature （SST） in the North Pacific Ocean is one of the possible causes in forming the decadal dry/wet trend and shift of the central part of North China.

关 键 词：中国 北方地区 干湿趋势 太平洋 相关性 

分 类 号：P46[天文地球—大气科学及气象学]