近50a来北方农牧交错带气温变化趋势及突变分析

利用北方农牧交错带内及邻近的共46个气象站点1957—2007年的气温数据资料,运用Mann-Kendall非参数检验法、R/S分析法,对气温变化趋势及突变特征进行了分析。结果表明,近50a来北方农牧交错带年、季气温普遍升高,20世纪90年代以后气温上升趋势显著,达到了99%的信度水平,年平均气温增温速率约为0.32℃/10a,明显高于全国和全球的气温增长率,其中冬季增温尤为明显,对全年增温贡献率最大;Hurst指数分析表明,整个北方农牧交错带年、季气温在未来仍表现出上升趋势,冬季的增温持续性最强;北方农牧交错带年、季升温幅度在空间上表现出一定的区域差异性,其年平均气温在90年代初发生了升温突变。

Variation Trend and Catastrophe Change of Air Temperature in the Farming-Pastoral Ecotone of Northern China during Recent 50 Years

Based on air temperature data in 1957—2007 from 46 meteorological stations in the farming-pastoral ecotone of northern China and its adjacent area, this paper analyzed the variation trend of air temperature and its catastrophe change using the nonparametric Mann-Kendall trend test and R/S methods. The results showed that the annual and seasonal mean air temperature in the research region had been rising during these 50 years, and a significantly increasing trend since the 1990s was detected, which arrives at 99% confidence level. The annual mean air temperature increased at a rate of 0.32℃/10a, which was higher than that of our nation and the whole world. This was mainly contributed by a higher rate of air temperature increase in winter. An analysis based on Hurst index shows that the annual and seasonal mean air temperature will increase continually in this area in the future, and the increasing trend will be more obvious in winter. The increasing range of annual and seasonal mean air temperature exhibited regional diversity. A catastrophe change of annual mean air temperature occurred in the early 1990s.