1980—2019年内蒙古地区雷暴时空分布与变化特征

Temporal and Spatial Distribution and Change Characteristics of Thunderstorm in Inner Mongolia from 1980 to 2019

利用内蒙古1980—2019年43个气象站的雷暴观测资料,应用数理统计、线性趋势分析等方法,对内蒙古雷暴的时空分布和变化特征进行了分析。结果表明:内蒙古雷暴分布与地形走向关系紧密,在西部偏东地区和中部偏西地区,为沿阴山山脉的东西走向,且阴山山脉南侧多于北侧;在中部偏东地区和东部地区,为沿大兴安岭的南北走向,且大兴安岭东侧多于西侧;西部偏西地区和东部偏东北地区为少雷区。与40年平均值相比,内蒙古20世纪80年代正距平区明显多于负距平区,之后负距平区明显增大,到21世纪10年代正距平区明显少于负距平区。内蒙古全年雷暴总站次数随时间呈显著减少趋势,且主要表现为夏季雷暴的减少。内蒙古雷暴季节性极强,集中发生在6—8月,7月达到峰值。内蒙古雷暴在一天中以前半夜20:00至次日1:00发生最多(占51%),其次为下午14:00—19:00(占22%)。内蒙古初雷暴日普遍出现在3—4月,40年中有28年出现在3月,初雷暴日在波动中推迟;终雷暴日普遍出现在10—11月,40年中有29年出现在10月,终雷暴日在波动中提前。一年中雷暴周期在波动中缩短。

Based on thunderstorm observation data of 43 weather stations in Inner Mongolia from 1980 to 2019,the temporal and spatial distribution and change characteristics of thunderstorm in Inner Mongolia were analyzed by methods of mathematical statistics and linear trend analysis.The results showed that the distribution of thunderstorms in Inner Mongolia was closely related to the topographic trend.In the east-west area and central-west area,the thunderstorms distributed from east to west along the Yinshan Mountains,and more on the south side than that on the north side.In the central-east area and east area,the thunderstorms distributed along the north-south direction of the Greater Khingan Mountains,and more on the east side than that on the west side.In the west-west area and northeast-east area,the thunderstorms distributed less.Compared with 40-year average in Inner Mongolia,the positive anomaly area was more than negative anomaly area in 1980s,then the negative anomaly area increased obviously.By the 2010s,the positive anomaly area was obviously less than the negative anomaly area.The total number of thunderstorm in Inner Mongolia showed a significant decreasing trend,and the main performance was the reduction of summer thunderstorms.The seasonality of thunderstorm in Inner Mongolia was very strong,which concentrated in June to August,and the peak was in July.Thunderstorm in Inner Mongolia occurred most frequently during 20:00 to 1:00 the next day(accounting for 51%),followed by 14:00-19:00 pm(accounting for 22%).In Inner Mongolia,the first thunderstorm day generally occurred in March to April,and it occurred in March for 28 years(in 40 years).The first thunderstorm day was delayed in fluctuation.The final thunderstorm day generally occurred from October to November,and it occurred in October for 29 years(in 40 years).The final thunderstorm day advanced in fluctuation.Thunderstorm cycles shortened in fluctuation over the course of a year.