【作者】 任菊章； 黄中艳； 郑建萌；

【Author】 REN Ju-zhang;HUANG Zhong-yan;ZHENG Jian-meng;Insititute of Plateau Meteorology,CMA;Yunnan Research Institute of Meteorology;Yunnan provincial Meteorological Society;Yunnan Climate Centre;

【机构】 中国气象局成都高原气象研究所； 云南省气象科学研究所； 云南省气象学会； 云南气候中心；

【摘要】 基于15个代表站1961-2010年气候资料,使用相对湿润度(M)指数和Morlet小波变换方法分析云南干旱气候的时空变化规律和特征。结果表明:雨季M指数主要反映降水对干旱的影响,干季M指数对气温、日照等共同引发的蒸散量变化有相当的响应。云南气候干湿年际波动大、年代际变化明显;雨季M指数主要表现为10~16a、6~8a和2~4a的周期性变化,干季M指数的变化周期以8a和4~6a为主;雨季M指数的地区性差别比干季大。云南的严重干旱均为上年雨季(或其末期)M指数偏小、随后的干季M指数典型偏低和当年雨季开始偏晚相叠加的结果。在全球变暖背景下,云南雨季有气候变干的趋势,干季大多区域呈干旱略加强趋势。近年云南多数区域M指数的主要变化周期相继进入谷值期,并与降水偏少同步出现,导致严重干旱发生频率加大。本研究对云南干旱预测、评估及其风险管理和应用决策有指导性和实用性。更多还原

【Abstract】 Based on the monthly precipitation and temperature data from 15 meteorological stations in Yunnan during 1961-2010, a relative moisture index(M) and Morlet Wavelet analysis method are used to analyze the characteristics of the temporal and spatial variation in Yunnan drought climate. The results show that, the M index mainly reflected the influence of precipitation on drought during rainy season in Yunnan while evapotranspiration was another important factor giving rise to the variation of M index during dry season. The fluctuation range of the dry-wet climate in Yunnan was great in its interannual change while being conspicuous in its interdecadal change. M index mainly showed periodical changes with 10-16, 6-8 years and 2-4 years in rainy season while its fluctuation cycles with 8 years and 4-6 years mostly appeared in dry season in five areas of Yunnan. And the regional difference of M index was bigger in rainy season than the one in dry season. The severe-drought incidents emerged in Yunnan on the condition that, the value of M index was smaller than normal in the rain season of last year along with its low value of dry season while rainy season came late in this year. On the background of global warming, the climate change presented drying trends in 5 areas of Yunnan in rainy season while showed the trends of strengthening by inches in most areas in dry season. Meanwhile, M index in main variation cycles entered into low-value stages in succession, accompanied by the cogradient occurrence of declining rainfall in most areas of Yunnan in recent years, which meant leading easily to the emerging of severe drought.更多还原