Instant tsunami early warning based on real-time GPS – Tohoku 2011 case study

A Hoechner,A Y Babeyko,S V Sobolev,M Ge

doi:10.5194/nhess-13-1285-2013

Abstract

Abstract. Taking the 2011 Tohoku earthquake as an example, we demonstrate the ability of real-time GPS to provide qualified tsunami early warning within minutes. While in earlier studies we demonstrated the power of the so-called GPS shield concept based on synthetic data, we here present a complete processing chain starting from actual GPS raw data and fully simulate the situation as it would be in a warning center. The procedure includes processing of GPS observations with predicted high precision orbits, inversion for slip and computation of the tsunami propagation and coastal warning levels. We show that in case of the Tohoku earthquake, it would be feasible to provide accurate tsunami warning as soon as 3 min after the beginning of the earthquake.

Highlights

Japan and in the Pacific, this event is the most extensively recorded megathruEstaevretnht eSveyr.sCteosmeismic deformation was recorded by the GEODNEyTnGaPmS iacrrsay (GSI, 2011)
Started after the event of Sumatra 2004, the concept of the “GPS shield” was proposed (Sobolev et al, 2006, 2007), where we suggested incorporating GPS-based tsunami early warning in all tsunami-prone areas worldwide, including Japan, and which is becoming an operative part of the German Indonesian Tsunami Early Warning System GITEWS (Babeyko et al, 2010; Behrens et al, 2010; Falck et al, 2010)
The estimated magnitude already corresponds to MW = 8.4 and warning levels show major tsunami warning for the Sendai prefecture

Summary

Introduction

Japan and in the Pacific, this event is the most extensively recorded megathruEstaevretnht eSveyr.sCteosmeismic deformation was recorded by the GEODNEyTnGaPmS iacrrsay (GSI, 2011). Deduced by sea floor geodesy (Sato et al, 2011). Source parameters were the scope of many investigations includijnogintinivnevresrisoinonosf(oRcoemanandoateatG, aslee.i,os2ms0i1cc2iwe; aYnvoteikffooictramest, as well as al., 2011). Most studies reveal a comInpsactrt uslmip edinsttraibtuitoionn (Pollitz et al., 2011), very high maximum Mslipeathndoadvseraagne dslip about twice as high as al., 2013). M (JMA) was the largest event ever instrumentally observed in able to provide a warning as early as 5 to 10 min after an. Working within this time limit, traditional seis-

Objectives

Methods

Results

Conclusion