摘要
从陇南市1971—2010年雷暴资料入手,分析了陇南山区近40年雷暴时空分布特征。结果发现,陇南市每年都有雷暴出现,平均每年176.5站日、每站每年约19.6日,雷暴一般出现在4—9月,其中,5—8月集中出现最多,占76%,造成的灾害损失最为严重。从陇南市雷暴年际变化趋势分析,目前,雷暴日数正处于明显的下降时期。因此,结合人口、GDP、耕地比等资料,利用ArcGIS软件,得到雷暴灾害危险性图层,再同承灾体易损性评价、灾害的孕灾背景进行叠加、合并以及等级划分操作,最后得到雷暴灾害的风险评估及其区划。结果表明,陇南市雷暴危险性等级宕昌、礼县和武都区白龙江流域最高,为雷暴高风险区,两当东南部、康县大部、武都东南部、文县南部最低,为雷暴低风险区。
Starting from the data of thun- derstorm in Longuan City from 1971 to 2010, the temporal-spatial characteristics and risk zonation of thunderstorm in Lunguanin recent forty years were ana- lyzed. The conclusion was as follows： the thunderstorm occurred every year in Longnan, which was up to 176.5 days a year on average, about 19.6 days at every station. The thunderstorm occurred be- tween April and September generally, which mainly concentrated between May and August, accounting for 76 percent, the damage in this time quantum was worst. According to the interannual vari- ation of the thunderstorm in Longnan City, the frequency of thunderstorm de- creased obviously at present. Combined with data about population, farmland ra- tio, GDP of Longuan City, etc., by the u- tilizing ARCGIS software, the maps of the possibility of thunderstorm disasters were gained. Then, by overlaying and u- niting of the background of weather dis- asters, the vulnerability of stricken things and compartmentalizing the hazard grade, the hazard attributions for thun- derstorm was achieved. From the map, it was concluded that： the risk grade of thunderstorm was the highest in Tan- chang County, Lixian County and the Bailong River basin in Wudu District, where there were high risk. The risk grade of thunderstorm was the lowest in the southeast of Liangdang County, the most part of Kang County, the southeastof Wudu District and the south of Wen County, where there were low risk.
出处
《农业灾害研究》
2013年第6期29-31,37,共4页
Journal of Agricultural Catastrophology
关键词
陇南山区
雷暴
分布特征
灾害风险区划
Longnan mountainous area
Thunderstorm
Distribution characteris-tic
Risk zonation
