Natural Hazards and Earth System Science www.nat-hazards-earth-syst-sci.net 1561-8633 1684-9981 10 7 2010 10.5194/nhess-10-1617-2010 http://www.nat-hazards-earth-syst-sci.net/10/1617/2010/ http://www.nat-hazards-earth-syst-sci.net/10/1617/2010/nhess-10-1617-2010.html http://www.nat-hazards-earth-syst-sci.net/10/1617/2010/nhess-10-1617-2010.pdf 1617 1627 2010-07-26 Source modeling and inversion with near real-time GPS: a GITEWS perspective for Indonesia A. Y. Babeyko babeyko@gfz-potsdam.de A. Hoechner S. V. Sobolev Deutsches GeoForschungsZentrum GFZ, Section 2.5, Potsdam, Germany We present the GITEWS approach to source modeling for the tsunami early warning in Indonesia. Near-field tsunami implies special requirements to both warning time and details of source characterization. To meet these requirements, we employ geophysical and geological information to predefine a maximum number of rupture parameters. We discretize the tsunamigenic Sunda plate interface into an ordered grid of patches (150×25) and employ the concept of Green's functions for forward and inverse rupture modeling. Rupture Generator, a forward modeling tool, additionally employs different scaling laws and slip shape functions to construct physically reasonable source models using basic seismic information only (magnitude and epicenter location). GITEWS runs a library of semi- and fully-synthetic scenarios to be extensively employed by system testing as well as by warning center personnel teaching and training. Near real-time GPS observations are a very valuable complement to the local tsunami warning system. Their inversion provides quick (within a few minutes on an event) estimation of the earthquake magnitude, rupture position and, in case of sufficient station coverage, details of slip distribution. Behrens, J., Androsov, A., Babeyko, A. 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