1974～2004年延河流域气候变化特征分析

Study on Characteristics of Climatic Variation in Yanhe Watershed during 1974-2004

[目的]分析1974～2004年延河流域气候变化特征。[方法]选取延河流域7个代表站点1974～2004年逐月气温、降水量资料,采用气候统计分析法、累积距平和信噪比等方法,对31年来该流域气温和降水变化进行分析,找出其变化特征和气候发生突变年。[结果]31年来延河流域气候变化以0.44℃/10a的速率变暖,年平均气温为9.4℃;四季均有增温趋势,其中冬季和春季平均气温增加明显,特别是90年代以后增温幅度变大。降水有减少趋势,其减少速率为26.3 mm/10a;四季中夏季和秋季降水减少明显,特别是90年代减少幅度最大。1996年是该流域气温突变年,1993年是气温转折年;1994年是降水量突变年,1990年是降水量转折年。[结论]该研究为延河流域农业生产、生活及灾害预防提供参考。

[Objective] The aim was to study the climate changes of Yanhe watershed during 1974-2004.[Method] The monthly temperature and precipitation during 1974-2004 in seven representative stations in Yanhe watershed were chosen.By dint of climate statistics analysis method,accumulated anomaly and signal/noise ratio method,the regional temperature and precipitation changes in recent 31 years were expounded and its changes features and climate mutation year were found out.[Result] The climate changes in Yanhe watershed in recent 31 years rose at a speed of 0.44 ℃/10a.The temperature increase range enlarged after 1990s.Precipitation decreased at a speed of 26.3 mm/10a.Precipitation reduced most distinctly in summer and autumn,and the reduction range enlarged in 1990s.1996 was the year of abrupt temperature changes year in the region.1993 was the year of temperature transition year.1994 was the year of precipitation mutation year.1990 was the year of precipitation transition year.[Conclusion] The study provided reference for the agricultural production,life and disaster pre-warning in Yanhe watershed.