河西走廊东部暴雨山洪地质灾害特征及预报预警技术研究

The Characteristics of Mountain Flood Geological Disasters and the Technology of Forecast and Early Warning in the east of Hexi corridor

摘要:

利用河西走廊东部1971—2023年山洪地质灾害资料及2016—2023年主汛期5～9月有完整资料的83个气象站逐时降水资料,运用统计学、主成因分析、二次衰减模型等方法在分析了河西走廊东部山洪地质灾害特征基础上,研究了预报预警技术。结果表明：(1)河西走廊东部山洪地质灾害分布呈现出从北向南,低海拔到高海拔逐渐增多的特点,由西南向东北递减,这与汛期的降水量分布规律相符合；(2)多因子建立的河西走廊东部山洪地质灾害精细化风险区划,对准确预报河西走廊东部山洪地质灾害及防灾减灾提供技术支撑；(3)利用综合致灾能力评估Ri指数,对照山洪地质灾害风险区划图,结合河西走廊东部气候、地形特点,确定山洪地质灾害危险度等级,较为精确的定量描述了山洪灾害和降雨之间的关系,在山洪地质灾害预报预警业务中发挥了重要作用；(4)确定的河西走廊东部暴雨山洪地质灾害气象预报预警等级及构建的预报预警模型还有待利用更长时间资料进一步优化完善。

Abstract:

Based on the geological disaster data of mountain torrents in the east of Hexi corridor from 1971 to 2023 and the hourly precipitation data of 83 meteorological stations with complete data from May to September of the main flood season in the east of Hexi corridor from 2016 to 2023, the characteristics of geological disasters of rainstorm mountain torrents in the east of Hexi corridor are analyzed by using statistics, main cause analysis, secondary attenuation model and other methods, and the prediction and early warning technology is studied. The results show that: (1) the distribution of mountain flood geological hazards in the east of Hexi corridor shows a gradually increasing trend from north to south, with a decreasing trend from southwest to northeast from low altitude to high altitude, which is consistent with the distribution pattern of precipitation during the flood season; (2) The refined risk zoning of mountain flood geological disasters in the east of Hexi corridor established by multiple factors provides technical support for accurate prediction of local mountain flood geological disasters and disaster prevention and reduction; (3) Using the comprehensive disaster causing ability assessment Ri index, comparing with the risk zoning map of mountain flood geological disasters, and combining with the climate and terrain characteristics , the risk level of mountain flood geological disasters in the east of Hexi corridor was determined. The relationship between mountain flood disasters and rainfall was quantitatively described more accurately, playing an important role in the prediction and early warning of mountain flood geological disasters; (4) The determined meteorological forecast and early warning grade of rainstorm and mountain torrent geological disasters in the east of Hexi corridor and the forecast and early warning model constructed need to be further optimized and improved by using longer time data