The partnership between the Tsunami Research Center at USC, the California Emergency Management Agency and the California Seismic Safety Commission let the State to be the first among all US States to complete the maps. The new generation of maps incorporates local and distant scenarios. Most of the hazard was dominated by offshore landslides, whose return period remains unknown but is believed to be higher than 1000 years for any given locale, at least in Southern California. Since the 1998 Papua New Guinea tsunami when the hazard from offshore submarine landslides was better understood (Bardet et al, 2003), the State of California funded the development of the first generation of maps, based on local tectonic and landslide sources. The need for new tsunami maps for California became clear since Synolakis et al (1998) described how inundation projections derived with inundation models that fully calculate the wave evolution over dry land can be as high as twice the values predicted with earlier threshold models, for tsunamis originating from tectonic source. The new maps offer improved coverage for many areas, they are based on the most recent descriptions of potential tsunami farfield and nearfield sources and use the best available bathymetric and topographic data for modelling. A new generation of tsunami inundation maps is now available for 17 coastal counties.
New Tsunami Inundation Maps for Californiaīarberopoulou, Aggeliki Borrero, Jose Uslu, Burak Kanoglu, Utku Synolakis, CostasĬalifornia is the first US State to complete its tsunami inundation mapping.