中文摘要：

利用1960年-2010年黄河流域夏季（6月-8月）月平均气温、降水量数据及逐月0℃高度探测资料，定性与定量分析了近51年来黄河流域夏季0℃层平均高度变化趋势及与历年气温、降水量及海拔高度变化之间的关系，并用Mann—Kendall法对年际0℃层高度变化进行了突变检验。结果表明：①黄河流域夏季0℃层平均高度近51年来总体呈“下降-平稳-上升”趋势，其中20世纪60年代至70年代中期经历了一个明显的下降阶段，70年代中后期至80年代后期变化相对平缓，90年代以后发生了突变；②夏季0℃层高度变化与地面气温、海拔高度的变化在同时间段内基本一致，呈正相关性；而与降水量变化表现出相反的变化趋势。

英文摘要：

Based on data of monthly mean air temperature, monthly mean precipitation data, and 0℃ level height detection material at 14 observation stations over the Yellow River basin in summer （from June to August） during the period 1960-2010, changing trends in summer 0℃ level average height, and its relationships with changes in air temperature, precipitation, and altitude were comprehensively analyzed. The mutation test of the Mann-Kendall （M-K） method was employed for detecting mutations in interannual summer 0℃ level height series. Results show that 1） the summer 0℃ level average height generally showed a ＂decliningstationary-rising＂ trend. It experienced a significant reduction from the 1960s to mid-1970s, a relative stable period from the 1970s to 1980s, and a mutation after the 1990s. Increases in 0℃ level height indicate that temperature at the lower level of the upper atmosphere is rising. It is demonstrated that there is a climate change in the upper air as well as on the surface; 2） Variation in summer 0% level height showed a generally consistent trend as variation in surface temperature with altitude; it exhibited positive correlation as opposed to variation trend in precipitation.