【摘要】 利用近 50年温度和降水资料研究了安徽夏季气候变化特征 ,解释了 2 0 0 3年夏季洪涝、高温等极端气候事件出现的必然性。研究结果表明 :(1 )近 50年来安徽夏季温度呈下降趋势 ,降水则呈增加趋势 ,两者变化是相协调的。目前夏季温度处于较低的气候基本态 ,降水处于高基本态。 (2 )无论是温度还是降水 ,其变率都在 2 0世纪80年代中后期开始上升 ,目前均处于高气候变率时期。降水的“两高”(高基本态和高气候变率 )结合决定了 2 0 0 3年夏季洪涝出现的必然性 ;温度的较低基本态决定了“凉夏”背景 ,但由于基本态的回升和变率的加大 ,仍会出现像 2 0 0 3年夏季的若干高温天气。 (3)最大熵谱估计表明 ,安徽夏季降水变化的主周期为 2 5年 ,反映了降水的准两年振荡特征更多还原

【Abstract】 Using data of summer temperature and precipitation in recent 50 years of Anhui Province, the climate change in summer season is analyzed and the inevitability of extreme climate events is explained. The results indicate that (1) Summer temperature decreased and precipitation increased in recent 50 years, so temperature is in a phase of low climate base state now and precipitation in high. (2) Climate variability also vary with time, and now both temperature and precipitation are in a phase of high climate variability so that we should be aware of frequent occurrence of extreme climate events such as flood, high temperature. (3) Maximum entropy spectrum analysis shows that the summer precipitation varies periodically for 2 to 3 year, with the character of QBO.更多还原