基于GIS的地质灾害气象预警方法初探

A case study on the meteorologic early-warning of geological hazards based on GIS

文章从预报预警工作的实际需要出发,以降雨为诱发因素,应用系统论的观点和综合分析方法,按照全面、简明、易于操作和注重实效的思路,利用GIS技术结合地质和气象资料分析,提出了基于GIS的地质灾害预报预警方法。其做法是:①在地质灾害调查区划成果基础上,利用GIS生成地质灾害易发程度区划图,完成全省地质灾害易发分区;②将影响灾害的地质环境条件和气象条件在GIS中叠加分析,判定诱发地质灾害的气象条件基本可分为当日暴雨-大暴雨型和前期累积降雨型两类,并以暴雨-大暴雨型诱发为主;③应用气象-灾害数据统计分析,综合考虑当日雨量与累积雨量的作用,结合易发分区条件构造了简明实用的预警指标预警标准综合判别表方法;在2004年用上述方法开展了地质灾害气象预警工作并取得了很好的效果。最后指出了在实际业务应用中需注意的问题及应采取的措施。

This paper set out from practical needs and according to the fact that geological disasters results trom integrateo effect of surrounding geological factors and meteorologic conditions, from the system point of view and based on current provincial work conditions. Applying synthetical analysis, taking into account an approach comprehensive ,simple ,practical and aim at actual effect, by using GIS technique and studying synthetically with geological and meteorologic data, the authors present a method based on the GIS technology to early warning of geological hazards. The main achievements includes as follow： （1）produced the geological hazards vulnerability degree distribution map based on investigation informations of geological hazards by the country department. （2） by synthetical analysis with geological and meteorologic conditions in the GIS, the meteorologic warning indexes to geological hazards in different vulnerable subareas were found out, and the authors pointed out that the meteorologic conditions inducing hazards can be largely divided into two models, namely timely rainstorm ＆ heavy rainstorm model and previously accumulative rainfall model, and it relies mainly on the former, （3）applying reliable observation data and combining with background of geological hazards vulnerability degree distribution, the authors synthetically analysed the effects of timely rainfall and accumulative rainfall, and brought forward a set of representative meteorologic warning indexes, and practically designed an applied integrated criterions table for hazards warning degrees. （4）proved it works well when taking such approach to test for disasters warning in 2004, and introduced the operational flow of geological hazards warning based on GIS. Finally, the authors pionted out the problems need to be noticed in practical application, and gave the improved measures can be taken. In conclusion, this paper put out a method which is reasonable, concise and practical, can be easily applied to the actual provincial operation of geological hazards warning .