Some evidence of drying trend over northern China from 1951 to 2004

查看全文 作　　者：MA Zhuguo1,2 & FU Congbin1,2 1. Key Laboratory of Regional Climate-Environment for Temperate East Asia, Chinese Academy of Sciences, Beijing 100029, China;2. START Regional Center for Temperate East Asia, Institute of Atmos-pheric Physics, Chinese Academy of Sciences, Beijing 100029, China 出　　处：《Chinese Science Bulletin》索引2006年第51卷第23期,共13页 基　　金：Thanks are given to two anonymous reviewers.This study is supported by the State Key Basic Development Planning Project(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：The surface wetness index, Palmer drought sererity index and the retrieval of soil moisture over China were calculated using monthly precipitation and monthly mean surface air temperature. Based on the contrast analysis of the variation of the above three indices and precipitation, the dry/wet spatio-temporal pattern of northern China in the last 54 years was revealed, and the evidence of drying trend over northern China was analyzed, especially. The results show the following four facts: (1) The drying trend is the main characteristic of the eastern part of Northwest China and the central part of North China since the 1980s and it was enhanced in the last 15 years mainly due to the precipitation decrease and the temperature increase; (2) During the last 54 years, there was only one dry/wet shift at the interdecadal scale occurring in the eastern part of Northwest China and the central part of North China in the late 1970s, which was related to 1977/1978 global abrupt change, whereas there were three shifts in Northeast China, one was in the mid 1990s and the other two were in 1965 and 1983, respectively; (3) Unlike the variation trend of other subregions of northern China, the western part of Northwest China is currently located in a relatively wetting period, which is weak-ened due to the temperature increase; (4) The extreme drought frequency is obviously increasing in the eastern part of Northwest China, the central part of North China and Northeast China since the 1980s, which is closely related to the precipitation decrease and temperature increase in these subregions. 关 键 词：中国北方 干燥趋向 干旱索引 气候背景