Internet information aided disaster assessment of great earthquake

The information on Internet is distributing in a large space scope and can be almost updated in real time at a short time period; especially, as “information highway”, Internet is a cheap information source, it costs less workload and time to collect information from Internet, and it can play a helpful role in disaster mitigation. The 5.12 Wenchuan earthquake is taken as a case study in this paper to develop a set of methods to aid the disaster assessment of the great earthquake from internet information. Firstly, the information of the damaged area was collected successively after the shock that were released on Internet website of the authoritative organization with data mining technology. The information was then analyzed, arranged and classified into three types, the information on damage distribution, the statistic data on death and injures, and those on building collapse rate in residential areas assessed by the remote sensing data. This information was further translated into “information based intensity”, and the locations of those residential areas with “information based intensity” were searched out from the fundamental geographic information database, and were stored into database together. The isoseismals were constructed by GIS spatial modeling tools from the experiential intensity attenuation relationships. A Human-computer interactive method was developed to improve the isoseismals successively by the data of information based intensity. The results at several time periods were compared with the ground survey which published a couple of months later, and showed that the isoseismals were improved step by step closely to the survey with the information amount increasing. On the 12th day after the earthquake, the improved isoseismals was already quite similar with the survey. The result can roughly show the actual damage situation, and provide quickly a support to the disaster relief.