【摘要】 为探究历史时期气候灾害特征及影响因子,建立了清代1644—1911年云贵地区的旱涝指数序列,采用滑动t检验和总体经验模态分解(EEMD)分析了清代云贵地区旱涝灾害的突变特征和多时间尺度周期性特征,研究表明:清代云贵地区旱涝指数整体较平稳,呈现先明显增加后减少,然后趋于平稳,清末又明显增加的趋势,旱涝指数序列具有多个跃变点,且具有显著的2.8a和6.6a年际周期,13.0a和40.2a的年代际周期.由旱涝灾害年次和年均县次比的空间分布图发现,其具有同旱同涝的空间分布特征.由于13.0a的周期与太阳黑子相对数序列的周期接近,故采用交叉小波分析着重探究了太阳黑子活动对云贵地区旱涝变化的影响,发现云贵地区旱涝指数序列同太阳黑子相对数序列在3～6a的时间尺度具有强凝聚性共振周期.更多还原

【Abstract】 With the increasing global climate change,the drought and flood disasters events of our country intensified in recent years,so it is necessary to study the characteristics and influencing factors of climate disasters during the historical period.In this paper,the drought and flood index series of Yunnan-Guizhou area from 1644-1911 was established.Sliding t-test was used to find the mutation points and Ensemble Empirical Mode Decomposition(EEMD)was used to analysis the periodicity of the sequence on different timescales.The results show that the drought and flood index in the Yunnan-Guizhou area is relatively stable which shows a significant decreased after increased and then leveled off,and the last significant increase trend.Drought and flood index sequence has multiple transition points and has the inter-annual scale period of 2.8 a,6.6 a,inter-decadal scale period of 13.0 aand 40.0 a.According to the spatial distribution maps and the average annual ratio of county maps of drought and flood disasters,it has been found that the drought and flood disasters have the same spatial distribution characteristics.Because of its 13.0 aperiod are close to those of sunspot,we used cross wavelet transform to analyze the influence of sunspot activity on the variation of drought and flood in Yunnan-Guizhou area.It is found that the sequence of drought and flood index in Yunnan-Guizhou area has strong cohesive resonance period at 3-6 atime scales with the sunspot relative number sequence.更多还原