The government is pursuing disaster risk reduction, urging society to prepare for and react to a major earthquake before it occurs, through the new information system. However, such proactive countermeasures based on uncertain disaster forecast information is a challenge with no precedent worldwide. Key organizations and the general public—those who receive and try to use this information—could be perplexed by the fact that a giant earthquake may strike but the chance of having one soon is much smaller than not having one.
 
To address this issue, the IRIDeS research group has decided to conduct an in-depth examination of the special information on the Nankai Trough earthquake from a variety of research fields. The research group thinks that providing a “second opinion” should be useful for the stakeholders to view the problem in different perspectives. The group also thinks that since the guidelines published by the Cabinet office are inevitably limited to general descriptions, providing more detailed and specific recommended solutions can complement the guidelines well. The research group is divided into three teams: the Hazard Assessment Team, the Countermeasures Team, and the Social Effects Team. The teams started examining the special information in each specialized field with inter-team discussions. The initial year of the whole research period of three years has just finished, focusing on Kochi Prefecture as a model area.

Primarily from the natural science and engineering perspectives, the Hazard Assessment Team aims at visualizing the diversity of scenarios that could happen after observation of a large earthquake or an anomalous slow slip, in which case the special information would be announced. Their research outcomes will facilitate the key organizations to overview the wide spectrum of possible scenarios and to better prepare. The team also plans to visualize the tsunami risk maps in the period of alert which is one or two weeks.

The Countermeasures Team will deliver recipes of recommended actions customized to different types of organizations so that they can create effective response plans in case of special information announcement. The team has been in collaboration with stakeholders in Kochi so that the recipes are effective in practical situations. They are currently focusing on the most challenging situation of a giant earthquake having struck on the farther side (that is, not much direct damage) and another one anticipated on the nearer side (which could cause tremendous damage). The team is seeking to promote the implementation of such recommendations through its integration with the general business continuity plans against Nankai Trough earthquakes. The team members are taking as important issues not covered by the government guidelines, such as sold-out stocks at local stores or traffic jams.

From engineering, neuroscience, and scientific communication perspectives, the Social Effects Team is exploring the interactions between the key organizations and society. The actions taken by the organizations have influence on society (other organizations and public) and the response of the society would inversely influence the actions of organizations. The team also focuses on the communication of the uncertain disaster risk information with the public. In the case of the Great East Japan Earthquake in 2011, gaps were observed between the public behavior anticipated bythe key organizations and actual public behavior. Insights can be obtained from such past cases for wiser actions on the future Nankai Trough earthquakes. The final goal of the team is to explore realistic and effective actions of key organizations and effective communication with the public.