【摘要】 基于1961—2019年贵州、湖南、江西191个气象站点电线积冰资料,统计分析了研究区域内电线积冰的日数、标准冰厚极值、最大连续积冰日数的时空分布特征以及电线积冰起止日的时间变化;构建电线积冰风险指数,评估了出现电线积冰的风险。结果表明:电线积冰日数整体呈下降趋势,在20世纪80年代达到最大值,月分布以1月出现最多,电线积冰以雨凇型积冰为主。标准冰厚极值集中在20～50 mm,极值大部分出现在湖南;大部分站点极值出现在2011—2019年。最大连续积冰日数集中在5～15 d,整体上贵州的最大连续积冰日数高于湖南和江西。电线积冰的起始日的年际变化整体上呈提前趋势,而终止日整体上呈推迟趋势。电线积冰风险指数年变化整体上呈减小的趋势;电线积冰的高风险区域主要位于贵州中西部、湖南中部和江西北部,风险指数大于0.6。更多还原

【Abstract】 Based on daily observation data of wire icing of 191 meteorological stations in Guizhou,Hunan and Jiangxi provinces from 1961 to 2019,the number of wire icing days,the extreme values of standard ice thickness,the maximum consecutive icing days,and the beginning and ending dates of wire icing in the study area are calculated.The wire icing risk indicator is constructed to evaluate the risk of wire icing.The results show that the number of wire icing days shows a slight downward trend on the whole in the past 60years,and it reached the maximum value in the 1980s.Wire icing occurs most in January.The extreme values of standard ice thickness are concentrated in 20—50 mm,and most of the extreme values are found in Hunan.The interdecadal distribution is extremely uneven,the most of the extreme values are seen in2011—2019.The maximum consecutive icing days are concentrated in 5—15 days.On the whole,the maximum consecutive icing days in Guizhou are more than in Hunan and Jiangxi.The beginning date of wire icing tends to be advanced in fluctuation,but the ending date tends to be postponed in fluctuation.The annual change of the wire icing risk indicator shows a decreasing trend.The high-risk areas for wire icing are mainly located in central and western Guizhou,central Hunan and northern Jiangxi,with a wire icing risk indicator greater than 0.6.更多还原