近48年中国的季节变化与极端温度事件的联系

利用中国1961—2008年752个站点逐日温度、气压、相对湿度和降水量资料,采用非线性相似度量方法对中国四季进行了划分,对比分析了中国的8个区域与全国整体的季节变化.此外,研究了中国极端温度频次的年际变化,并通过相关分析和敏感性试验探讨了中国近48年四季变化与极端温度事件的联系.结果表明:1)随着全球变暖中国大部分地区春、夏季起始时间提前,持续时间延长;秋季起始时间变化不大,但持续时间延长;冬季起始时间推后,持续时间显著缩短.2)随着夏季延长,除华东以外中国大部分地区极端高温频次增加;随着冬季缩短,中国关键词：非线性相似度量方法季节变化极端温度

Seasonal changes in China during recent 48 years and their relationship with temperature extremes

With nonlinear similarity method, we divised the seasons for whole China on the basis of daily mean temperature, pressure, relative humidity and precipitation at 752 stations for the period 1961—2008, and analyze the seasonal division for eight regions of China and seasonal times. In addition, the relevant statistic data are established which contain the annual variation in frequency of extreme temperature in China. By combining these two research findings, their relationship over the past 48 years is found through correlation analysis and sensitivity test. The results show that: (1) in most areas of China, the spring and summer starting time move up, their durations are extended, autumn starting time changes a litter, and its duration is extended, while winter is pushed back the starting time, and its duration is shortened. (2) With the summer extending, the frequency of extreme high temperature is increased in most areas of China except East China, while the shortening of winter results in the frequency of extreme low temperature declining markedly. (3) The existence and the annual change of extreme high and low temperature are the reason why the lengths of summer and winter change, and they are also the main reason why the substantial fluctuations of the lengths of summer and winter take place.