Ice distribution and ice risk assessment map were mapped in Zhejiang province. First, based on icing numerical model, ice disas-ter analysis during 2005-2014 was carried out hourly on 0.01°× 0.01° grid. Then using the Gumbel function, the extreme value distribution of each grid was depicted, and Zhejiang province ice distribution was mapped. Secondly, based on the comparative analysis of multiple fac-tors, tower ice downscaling scheme was established based on DEM data. Finally, based on the methodology of regional disaster risk assess-ment, vulnerability assessment model was selected to quantitatively evaluate the risk of ice disaster along transmission line in Zhejiang prov-ince on account of an index of failure rate of towers. The results showed that, in Zhejiang province, icing zones present zonal distribution, and the strongest ice zone is the middle one. In the current climate, if we ignore the human factor, ice disaster risk in the north and central zone of Zhejiang province is relatively high.%以浙江省为例,进行省域冰区图绘制和杆塔尺度的输电线路评估.首先,利用覆冰生成数值模式,针对2005—2014年覆冰灾害进行了逐小时0.01°×0.01°分辨率的覆冰过程反演,结合Gumbel极值分布刻画各栅格超越概率分布并绘制浙江省冰区图;其次,通过多因素比较分析,建立基于高程要素的杆塔覆冰降尺度方案;最后,基于区域灾害风险评估方法,选取易损性评估模型,对浙江省输电线路覆冰灾害下的杆塔失效率给出了定量评估.结果显示,浙江省冰区呈北、中、南带状分布,且中部覆冰带可能强度最大;在当前气候背景条件下,忽略人为抗冰、融冰等作用,浙江省中部及北部的输电线路覆冰风险相对较高.
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