大气科学学报2025，Vol.48Issue(5)：705-722,18.DOI:10.13878/j.cnki.dqkxxb.20250521002
2023年12月皖南山区输电线路连续两次覆冰的天气学成因及微气象差异研究
Meteorological drivers and micrometeorological variability of two consecu-tive icing events on power transmission lines in the mountainous region of southern Anhui in December 2023
摘要
Abstract
With the intensification of climate change,icing disasters on power transmission lines have become in-creasingly frequent,particularly in mountainous regions where complex topography amplifies micrometeorological variability.Icing poses a significant threat to grid stability and power supply security.Although substantial progress has been made in understanding individual icing events,the physical mechanisms governing the rapid succession of different icing types-such as glaze ice and mixed ice accretion-on the same transmission line remain insuffi-ciently understood.This study analyzes two consecutive icing events that occurred in December 2023 in the moun-tainous region of southern Anhui Province,China.Using ERA5 reanalysis data,radiosonde soundings,surface weather station observations,and tower-based ice thickness monitoring,we investigate the atmospheric conditions,micrometeorological drivers,and ice evolution patterns associated with each event.Particular attention is given to the roles of temperature structure,vertical motion,solar radiation,and vorticity dynamics in the formation and ab-lation of ice,as well as to the interactions between synoptic-scale circulation and terrain-induced microclimates. The first event,dominated by glaze ice,resulted from the southward intrusion of cold air from the Baikal trough interacting with a warm,moist air mass ahead,producing a pronounced temperature inversion.A warm layer at 700 hPa above a sub-zero layer below 800 hPa facilitated the formation of supercooled water droplets that froze on contact with the conductors,reaching a maximum thickness of 14.2 mm and a peak growth rate of 9.1 mm·h-1.In contrast,the second event was characterized by mixed ice accretion,driven by the eastward displace-ment of the Mongolian high and the northward extension of the western Pacific subtropical high.This circulation pattern produced a fully sub-zero temperature column and widespread snowfall,allowing both ice crystals and freezing droplets to adhere directly to the conductors,with a maximum thickness of 24.5 mm and a peak growth rate of 17.1 mm·h-1.The presence or absence of a temperature inversion was identified as the key factor distin-guishing the two icing types.Both ablation phases coincided with sharp increases in net solar radiation and the de-velopment of a characteristic vorticity structure,with positive vorticity aloft and negative vorticity near the sur-face,which enhanced atmospheric stability and radiative melting.The second event also involved spontaneous ice shedding due to excessive accumulation,emphasizing the need for timely manual intervention in severe cases.Ver-tical motion analysis revealed that glaze ice formation was linked to inversion-induced convection,while mixed ice accretion was associated with downdrafts and low-level convergence. These results demonstrate that small-scale differences in atmospheric structure and terrain can lead to sub-stantial variations in icing behavior.The study provides new insight into the dynamics of multi-type,multi-stage icing events in complex terrain and highlights the limitations of relying solely on standard meteorological indica-tors for prediction.The findings underscore the importance of combining mesoscale circulation analysis with real-time surface observations and tower-based monitoring to improve early warning systems and optimize de-icing op-erations.Future research should focus on integrating high-resolution numerical modeling,real-time sensor net-works,and intelligent image analysis systems to better capture terrain-induced icing variability,enhance icing-type classification,and support predictive maintenance in critical grid regions.Such advancements will be essential for strengthening grid resilience under a warming climate with more frequent extreme weather events.关键词
输电线路/连续覆冰事件/雨凇/混合凇/大气环流/微气象Key words
transmission line/consecutive icing event/glaze ice/mixed ice/atmospheric circulation/micrometeor-ology引用本文复制引用
杨元建,白森,周波涛,陈泽昌,宁贵财,张文杰,陆正奇,王路瑶,易雨荻,赵珈锐,何佳信..2023年12月皖南山区输电线路连续两次覆冰的天气学成因及微气象差异研究[J].大气科学学报,2025,48(5):705-722,18.基金项目
国家重点研发计划项目(2023YFF0805704) （2023YFF0805704）
国家自然科学基金项目(42201053) （42201053）
