Seismic Ground Disaster Assessment System (SGDAS) of GSI and its scope

抄録

The Geospatial Information Authority of Japan (GSI) developed the Seismic Ground Disaster Assessment System (SGDAS) in 2012 for the purpose of disaster response immediately after an earthquake, even at night, and it became officially operational in June 2019. SGDAS automatically estimates the area and scale of landslides and liquefaction after receiving seismic intensity distribution data, and generates a PDF report and sends emails to disaster response administrative officials. However, SGDAS was developed more than 10 years ago with data up to 2012, and subsequent disasters were not considered. Therefore, we are currently carrying out a five-year R&D project (FY 2021-25) to improve the estimation accuracy of the system. The project began with statistical comparison of damage maps of ground disasters and landslide/liquefaction estimation results to assess the current state and future directions. The results indicate needs for a new zoning of geological and geomorphological conditions based on the amount and type of landslides, additional information on seismic shaking, and a geomorphological map with better representation of small landforms in plains. We also conducted user questionnaires and interviews to understand user needs, which showed that oversight was more problematic than overestimation. We hope that our experiences will be useful to many other countries and institutions facing similar challenges.