Journal cover Journal topic
Natural Hazards and Earth System Sciences An interactive open-access journal of the European Geosciences Union
Nat. Hazards Earth Syst. Sci., 10, 1359-1372, 2010
© Author(s) 2010. This work is distributed under
the Creative Commons Attribution 3.0 License.
25 Jun 2010

Simulation of space-borne tsunami detection using GNSS-Reflectometry applied to tsunamis in the Indian Ocean
R. Stosius1, G. Beyerle1, A. Helm1,*, A. Hoechner1, and J. Wickert1 1Deutsches GeoForschungsZentrum GFZ, Telegrafenberg, 14473 Potsdam, Germany
*now at: Astrium Space Transportation, 88039 Friedrichshafen, Germany
Abstract. Within the German-Indonesian Tsunami Early Warning System project GITEWS (Rudloff et al., 2009), a feasibility study on a future tsunami detection system from space has been carried out. The Global Navigation Satellite System Reflectometry (GNSS-R) is an innovative way of using reflected GNSS signals for remote sensing, e.g. sea surface altimetry. In contrast to conventional satellite radar altimetry, multiple height measurements within a wide field of view can be made simultaneously. With a dedicated Low Earth Orbit (LEO) constellation of satellites equipped with GNSS-R, densely spaced sea surface height measurements could be established to detect tsunamis. This simulation study compares the Walker and the meshed comb constellation with respect to their global reflection point distribution. The detection performance of various LEO constellation scenarios with GPS, GLONASS and Galileo as signal sources is investigated. The study concentrates on the detection performance for six historic tsunami events in the Indian Ocean generated by earthquakes of different magnitudes, as well as on different constellation types and orbit parameters. The GNSS-R carrier phase is compared with the PARIS or code altimetry approach. The study shows that Walker constellations have a much better reflection point distribution compared to the meshed comb constellation. Considering simulation assumptions and assuming technical feasibility it can be demonstrated that strong tsunamis with magnitudes (M) ≥8.5 can be detected with certainty from any orbit altitude within 15–25 min by a 48/8 or 81/9 Walker constellation if tsunami waves of 20 cm or higher can be detected by space-borne GNSS-R. The carrier phase approach outperforms the PARIS altimetry approach especially at low orbit altitudes and for a low number of LEO satellites.

Citation: Stosius, R., Beyerle, G., Helm, A., Hoechner, A., and Wickert, J.: Simulation of space-borne tsunami detection using GNSS-Reflectometry applied to tsunamis in the Indian Ocean, Nat. Hazards Earth Syst. Sci., 10, 1359-1372,, 2010.
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