近51年川滇地区气候暖干化与旱涝灾害趋势判断

为揭示川滇地区气候特征与旱涝灾害趋势，以川滇地区70个气象站点1961～2011年的逐月气温、降水资料为基础,采用线性回归、五年滑动平均、M K突变检验、反距离加权空间插值、Z指数法、Morlet小波变换等方法，对川滇地区气候变化特征与旱涝灾害进行了分析。结果表明：近51 a川滇地区气温以021℃/10 a的速率增加；降水量以1076 mm/10 a的速率减少；尤其是20世纪90年代末期以来正经历着以增温和变干为趋势的气候变化特征，气候暖干化趋势明显。近51 a川滇地区年旱涝灾害总的趋势是向干旱发展，以2000年为转折点，2000年以前该区多涝灾，2000年后多旱灾，这与该区的气温与降水变化一致，气候暖干化的结果直接导致了旱灾加剧。川滇地区春、冬两季旱涝年际周期变化规律强，Z指数呈上升趋势，降水量增加；夏季旱涝周期变化十分显著，旱涝灾害程度加剧，干旱化趋势明显；秋季旱涝变化周期性不强，呈弱干旱化趋势发展

CLIMATE WARMING DRYING AND DROUGHT FLOOD TENDENCY JUDGMENT OF SICHUAN YUNNAN REGION IN RECENT 51 YEARS

The purpose of this article is to reveal the climatic characteristics and trends of flood and drought in Sichuan Yunnan region.By using methods of linear regression,the five year moving average,Mann Kendall non parametric statistical tests,inverse distance weighted spatial interpolation,the time change trends and space distribution characteristics of temperature and precipitation were analyzed based on the monthly temperature and precipitation data collected from 70 meteorological stations in this area from 1961 to 2011.On this basis,drought flood index model was constructed by using Z index,and the drought flood time evolution was analyzed by using Morlet wavelet transform.Results showed that:temperature presented an increasing trend over the last 51 years in this area,with a rate of 0.21℃/10 a and a warming trend coefficient as high as 0.71; the temperature had a significant long term warming trend; the annual average temperature was the lowest in west Sichuan plateau and the highest in the south of Yunnan; altitude was the most important factors affecting the temperature.The annually precipitation showed an decreased trend in the past 51 years in this area,with a rate of 10.76 mm/10 a.With the influence of southwest monsoon and altitude,the precipitation was comparatively low in west Sichuan plateau and the surrounding area of southwestern Sichuan Basin;the precipitation was relative abundant in Sichuan Basin,the precipitation was the most abundant in southwest of Yunnan.The Sichuan Yunnan region was experiencing climate warming and precipitation reducing period since the late nineteen ninties; the trend of climate warming and drying was clearly in this area.This area became increasingly dry in recent 51 years and 2000 was a turning point; this area was flood before 2000 and drought after 2000,being coherent with the temperature and precipitation changes in this area; increasing temperature and decreasing precipitation in this area led to intensified drought directly.The drought and flood had a strong interannual periodic variation in spring and winter.Z index showed an upward trend,precipitation was increased; the drought trend was obvious in summer and autumn; the periodic variation of drought and flood was strong in summer,the degree of drought and flood was intensified; the drought and flood periodic variation was not strong in autumn,it had a weak drought trend.There was an obvious waterlogging to drought transformation trend in summer and autumn of this area,and attention should be paid to the drought control work