Local Source Tsunami Inundation Modelling for Poverty Bay, Gisborne

After the Boxing Day 2004 Sumatran Tsunami, a review of tsunami hazard and risk for New Zealand identified Gisborne as the urban area with the greatest risk. Gisborne could experience gt;500 fatalities and extensive damage to infrastructure during a severe tsunami. The severity of a tsunami is likely to be low for distance sources given the effectiveness of the Pacific Tsunami Warning System. However, there is a substantial risk from local sources, as no local warning system of any kind exists. Prompt evacuation is probably the most cost-effective tsunami mitigation strategy available for New Zealand coastal locations, including Gisborne. This requires both knowledge of the extent of tsunami inundation, and sufficient warning of the tsunami arrival. Hence, there are two main objectives for this investigation: 1. Determine the likely extent of tsunami inundation for Gisborne City and surrounding populated coastal locations in Poverty Bay, using a combination of hydrodynamic tsunami modelling and GIS. The modelling will simulate historical events, particularly the largest historical tsunami, the May 1947 local tsunami. Modelling will consider potential events based on the Maximum Credible Earthquake for local sources associated with the Hikurangi Deformation Front. 2. Create inundation maps of Poverty Bay that can be used for future town planning and emergency plans

The GeoClaw software for depth-averaged flows with adaptive refinement

Many geophysical flow or wave propagation problems can be modeled with two-dimensional depth-averaged equations, of which the shallow water equations are the simplest example. We describe the GeoClaw software that has been designed to solve problems of this nature, consisting of open source Fortran programs together with Python tools for the user interface and flow visualization. This software uses high-resolution shock-capturing finite volume methods on logically rectangular grids, including latitude--longitude grids on the sphere. Dry states are handled automatically to model inundation. The code incorporates adaptive mesh refinement to allow the efficient solution of large-scale geophysical problems. Examples are given illustrating its use for modeling tsunamis, dam break problems, and storm surge. Documentation and download information is available at www.clawpack.org/geoclawComment: 18 pages, 11 figures, Animations and source code for some examples at http://www.clawpack.org/links/awr10 Significantly modified from original posting to incorporate suggestions of referee

On the use of finite fault solution for tsunami generation problems

The present study is devoted to the problem of tsunami wave generation. The main goal of this work is two-fold. First of all, we propose a simple and computationally inexpensive model for the description of the sea bed displacement during an underwater earthquake, based on the finite fault solution for the slip distribution under some assumptions on the dynamics of the rupturing process. Once the bottom motion is reconstructed, we study waves induced on the free surface of the ocean. For this purpose we consider three different models approximating the Euler equations of the water wave theory. Namely, we use the linearized Euler equations (we are in fact solving the Cauchy-Poisson problem), a Boussinesq system and a novel weakly nonlinear model. An intercomparison of these approaches is performed. The developments of the present study are illustrated on the 17 July 2006 Java event, where an underwater earthquake of magnitude 7.7 generated a tsunami that inundated the southern coast of Java.Comment: 31 pages, 10 figures, 3 tables. Other author's papers can be downloaded at http://www.lama.univ-savoie.fr/~dutykh

Training of Crisis Mappers and Map Production from Multi-sensor Data: Vernazza Case Study (Cinque Terre National Park, Italy)

This aim of paper is to presents the development of a multidisciplinary project carried out by the cooperation between Politecnico di Torino and ITHACA (Information Technology for Humanitarian Assistance, Cooperation and Action). The goal of the project was the training in geospatial data acquiring and processing for students attending Architecture and Engineering Courses, in order to start up a team of "volunteer mappers". Indeed, the project is aimed to document the environmental and built heritage subject to disaster; the purpose is to improve the capabilities of the actors involved in the activities connected in geospatial data collection, integration and sharing. The proposed area for testing the training activities is the Cinque Terre National Park, registered in the World Heritage List since 1997. The area was affected by flood on the 25th of October 2011. According to other international experiences, the group is expected to be active after emergencies in order to upgrade maps, using data acquired by typical geomatic methods and techniques such as terrestrial and aerial Lidar, close-range and aerial photogrammetry, topographic and GNSS instruments etc.; or by non conventional systems and instruments such us UAV, mobile mapping etc. The ultimate goal is to implement a WebGIS platform to share all the data collected with local authorities and the Civil Protectio