基于综合气象干旱指数的1961—2012年阿勒泰地区干旱时空演变特征

Spatio-temporal variation of drought condition during 1961 to 2012 based on composite index of meteorological drought in Altay region,China

基于阿勒泰地区7个气象站1961—2012年的逐日气温、降水等气象资料,运用趋势分析法、M-K突变检验法、小波分析法并结合Arc GIS软件,探究了阿勒泰地区干旱的时空演变特征.结果表明:综合气象干旱指数能较好地反映阿勒泰地区干旱状况.研究期间,阿勒泰地区虽然年和四季的干旱频次和不同等级干旱覆盖范围都呈减少趋势,但是旱情仍较为严重,年和季节的干旱发生频繁,且多年存在重旱和特旱发生在整个阿勒泰地区;秋季和冬季的干旱频次分别在1997和1983年发生减少突变,夏季的干旱频次首先在1962年发生增加突变,随后在1991年发生减少突变,年均和春季的干旱频次无突变发生;年和四季的干旱频次都存在明显的周期性.干旱频次和不同干旱等级在空间上的分布表明,东部清河县旱情较为严重,中部阿勒泰市、富蕴县、布尔津县、福海县旱情次之,西部地区的哈巴河和吉木乃县的旱情较轻.

Based on the daily meteorological data of seven stations in Altay study investigated the temporal （seasonal, inter-annual and decadal ） and drought by using composite index of meteorological region, spatial China, this variations of drought, as well as trend analysis, M-K abrupt analysis, wavelet analysis and interpolation tools in ArcGIS. The results indicated that the composite index of meteorological drought could reflect the drought condition in Ahay region well. Although the frequency and the covered area of both inter-annual and seasonal droughts presented decreasing trends in the recent 52 a, the drought was still serious when considering the annual frequencies of inter-annual and spring droughts had no abrupt changes, whereas the drought. The frequencies inter-summer, autumn and winter droughts had abrupt changes during the past 52 a. A significant periodic trend was also observed for the frequencies of inter-annuM and seasonal droughts. The dis- tribution of frequency and covered area suggested that the conditions of drought were heavily serious in Qinghe County, moderately serious in Ahay City, Fuyun County, Buerjin County and Fuhai County, and slightly serious in Habahe County and Jimunai County.