长江中下游地区类寒潮发生频次的变化特征分析

本文采用中国国家气候中心提供的1957-2008年中国753个台站逐日13温度资料,挑选出长江中下游地区(27.5°～32.5°N、112°～123°E)的51个测站,对该地区类寒潮发生频次特征进行分析,得出主要结论:长江中下游地区类寒潮的发生随着全球变暖的气候趋势,总体频次减少.有明显的年代际特征,20世纪60-80年代,类寒潮发生频次逐渐减少,90年代类寒潮又略增多,1973年前后出现突变.长江中下游地区主要以5年和14年信号周期变化,长江中下游地区类寒潮发生频次最高的月份分别为每年3月和11月,但存在明显的年际差异,年际差异最大的区域在皖南、赣北和浙西.

Analysis of the Frequency Characteristics of the Similar Cold Wave in the Middle and Lower Reaches of the Yangtze River

By virtue of the daily surface temperature data at 753 stations from the National Climate Center in China during 1957 to 2007, the 51 stations within the area of 27.5°-32.5°N, 112°-123°E are selected for the Middle and Lower Reaches of the Yangtze River, and the characteristics of the similar cold wave frequency in the area are analyzed. The main conclusions reached are that the frequency in the area is reducing due to the global warming. From decadal changes, the frequency of the similar cold wave is gradually reduced in 1960s-1980s of the twentieth century and slightly increased in the 1990s. Abrupt change occurs around 1973. Cyclic changes of the 5a signal and the 14a signal are the main in the area and months are March and November each year, in which the highest frequency of the similar cold wave occurred. However, there are interannual differences for these changes. And the greatest different regions are in the southern Anhui, northern Jiangxi and western Zhejiang.