湖北省电线积冰日数气候特征与大气环境异常的关系研究

The relationship between climate characteristics of wire icing days in Hubei Province and atmospheric general circulation anomalies

利用1980—2014年湖北省11个气象台站电线积冰观测资料以及Hadley海温资料、NCEP再分析资料,分析湖北省冬季(11—3月)电线积冰日数的气候变化特征;在此基础上,分析积冰异常年秋冬海气场变化。结果表明,湖北省电线积冰集中在钟祥、荆州、襄樊、仙桃和随州等5站,占11站电线积冰总日数的73%。电线积冰在当年11月至次年3月均有出现,积冰日数在1990年代初出现显著减少趋势。湖北省电线积冰异常偏多年,9—11月热带中东太平洋出现El Nino型异常海温分布,同期冬季孟加拉湾和南海的水汽向北输送至湖北,湖北水汽偏多,同时湖北受贝加尔湖异常反气旋东南侧东北气流和中国东部沿海异常反气旋西北侧偏南气流共同作用,有利于降水发生和积冰出现。

The daily wire icing data at 11 meteorology stations over Hubei Province, sea surface temperature （SST） from Hadley Centre, and reanalysis dataset from NCEP from 1980 to 2014 were used to analyze the climatic variation characteristics on the wire icing days in winter （from November to March） in Hubei. Moreover, we analyzed the field of sea temperature and atmosphere in the fall and winter of the anoma- lous wire icing years. The results indicate that the wire icing days distribute mainly in five cities （towns） namely Zhongxiang, Jingzhou, Xiang- fan, Xiantao and Suizhou in Hubei, accounting for 73% of the total icing days of 11 stations. Wire icing clays generally are observed from No- vember of the current year to March of the next year in Hubei, and show a significant decreasing trend during the early 1990s. In the anoma- lously more icing years, the anomalous SST distribution with El Nino pattern is found over the central and eastern Pacific in tropics from Sep- tember to November of the previous year. In the same period, water vapor from the South China Sea and the Bay of Bengal in winter is north- ward conveyed to Hubei, and northeast airflow in southeast side of Lake Baikal anomalous anti-cyclone and southerly airflow in northwest side of anomalous anti-cyclone at the coast of eastern China interact on Hubei, which is favorable to the occurrence of precipitation and the emergence of icing in Hubei Province.