摘要
利用无锡市1959~2002年共44a的逐日最低气温资料,分析了无锡寒潮发生的特点。分析结果表明:无锡寒潮的年发生次数有线性减少趋势;寒潮减少主要发生在10月、12月、4月。分年代看,从20世纪60年代到80年代逐年代减少,但90年代又增多。寒潮减少与降温幅度减小、最低气温升高有关,其中最低气温升高是其主要影响因素。特征区域的500hPa高度场偏高是寒潮发生次数减少的直接原因。最后,针对多寒潮年和少寒潮年的环流特点,给出了500hPa典型距平场特征。
Based on the daily low temperature from 1959 to 2002, the characteristics of Wuxi's cold wave are analyzed. The results show that the yearly frequency was linear decreasing, and the decreasing mainly happened in October, December and April. Frequency of cold waves was decreasing from 1960s to 1980s, but increasing in 1990s. The efficient amse of decreasing was the abnormity of position field. At last, the representative deflection fields of 500hPa are drawn.
出处
《暴雨灾害》
2007年第2期139-143,共5页
Torrential Rain and Disasters
关键词
无锡
寒潮
典型距平场
Wuxi city
Cold wave
Representative deflection fields