The status of earthquake early warning around the world:
An introductory overview

Richard M Allen
Seismological Laboratory, University of California, Berkeley
Paolo Gasparini
University of Naples, Italy
Osamu Kamigaichi
Japan Meteorological Agency
Maren Bose
California Institute of Technology

Seismo. Res. Lett., 80 (5) p682-693, doi: 10.1785/gssrl.80.5.682, 2009.

Part of a special issue on Earthquake Early Warning Seismo. Res. Lett., 80 (5) 2009.

Download a reprint: AllenEtAlSRL2009.pdf

Today, Japan has a nationwide, publicly available earthquake early warning (EEW) system, and the Mexico City system, operational since 1991, has been expanded to include Guerrero and Oaxaca. Taiwan, Istanbul and Bucharest have active systems providing warning to one or more users. Real-time testing of EEW is underway using seismic networks in Italy, Switzerland, China, Hawaii and California. In California, real-time testing has demonstrated proof-of-concept by generating hazard information before ground shaking was felt. This rapid development of EEW capabilities over the last 5 years has moved the community beyond the question of whether EEW is scientifically and technically possible to the question of when it is most useful and how it should be implemented. This special issue of Seismological Research Letters contains a series of papers on this topic. This introductory paper summarizes the methodologies undergoing testing around the world and details the current uses of early warning, as well as the successes, and failures, of these systems.

Download a reprint: AllenEtAlSRL2009.pdf