近0.5ka广东省干湿演变探讨

Dry and Wet Evolutions in Guangdong Province during the Last 500 Years

采用相关系数、波谱分析等方法对近0.5 ka以来广东省的干湿变化及近期演变趋势进行分析。研究表明,厄尔尼诺事件与粤西、粤北地区的旱灾具有显著正相关,一定程度上加剧了两地的旱涝分布格局;湿润指数序列与格陵兰冰芯δ18O记录、中国东部冬温序列存在较好的对应关系,呈现出典型的季风区水热配置模式;周期分析揭示了干湿演变序列中一系列与太阳活动相关的特征周期,表明其驱动机制可能与包括天文因素在内的多种影响因素有关。湿润指数的多尺度分析表明,21世纪中叶以前,广东省将处于偏旱状态,2040(±5)年后将会出现较大强度的涝情,在未来几十年甚至百年内,广东省的干湿变化幅度有增大的趋势。

Based on the historical records in Guangdong Province during the last 0. 5 ka,the dry--wet index sequence was reconstructed and analyzed by the correlation analysis, wavelet analysis and the power spectrum analysis. The results indicate that： 1） The E1 Nino events have evident correlations with the droughts happened in the west and north of Guangdong Province, which intensified the dryness and wetness distribution patterns in these areas in a certain degree, 2） Good correspondence relations exist among the dry--wet index sequence, Greenland ice core oxygen isotope record and the winter--half--year temperature sequence in the eastern China,which showed an apparent monsoonal disposal pattern of moisture and temperature, 3） By applying the wavelet analysis to deal with the data, several apparent periodicities are revealed, among which some can be attributed to the solar activities. At the same time, the ENSO event, monsoon （especially the East Asia monsoon） activity and the human activity may also have some influences on the periodicities of the climatic changes in Guangdong Province. 4） Guangdong will persist in dry periodicity before 2040（±5） though some little waterlogged periodicity will also exist in this interval,and after that great floods maybe take place in Guangdong. The authors think that the variety range of the dryness and wetness has increasing tendeney in Guangdong Province in future several decades even hundred years.