Special Issue on Challenges of Earthquake Forecast Research Illuminated by the 2011 Tohoku-Oki Earthquake
Naoshi Hirata and Aitaro Kato
The 2011 off the Pacific coast of Tohoku Earthquake, hereafter referred to as Tohoku-Oki earthquake, occurring off northeastern Japan’s Pacific coast on March 11, 2011 had a moment magnitude of 9.0 and generated a tsunami responsible for most of the deaths of the event’s 19,000 victims. Identifying scientifically what happened before, on, and after March 11 is one starting point for a discussion on how to reduce casualties and mitigate the impact of such natural disasters. The 14 papers in this special issue cover incidents related to pre-, co- and post-seismic phenomena, including volcanoes. Three papers discuss why and how such a large quake occurred. Three more papers go into the implications of short- and long-term crustal deformations seen in northeastern Japan. Four papers detail short- and long-term phenomena leading to the Tohoku-Oki quake. Two papers discuss real-time tsunami forecasting based on off-shore and on-shore geodetic, seismic and tsunami observation data. The last two papers explore the effects of the 2011 temblor on volcanic phenomena.
The magnitude 9.0 produced in the 2011 event is the largest historically recorded in Japan and may not necessarily have been anticipated beforehand, and the generation mechanism behind such a gigantic occurrence is not yet completely understood. Even so, preparations should be made for such earthquakes in other parts of Japan and in other countries. The Nankai trough is an example of areas that require our attention.
A national project for observation and study for earthquake prediction is now being integrated into a new program, Earthquake and Volcano Hazards Observation and Research Program (2014-2019). Studies presented in this special issue are also being supported in part by this program.
We are certain that readers will find that this special issue will contribute much to our understanding of gigantic earthquakes and at least some of the measure to be taken in preparation for such natural phenomena. Finally, we extend our sincere thanks to all of the contributors and reviewers involved with these articles.