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  • Historical settlement patterns have resulted in Australia having most of its major city developments situated on the coastline. Storm tides are a major natural hazard for coastal regions. Severe storms and cyclones contribute 29 per cent of the total damage cost from natural hazards to the Australian community. In 1999 prices, this amounts to A$40 billion during the period 1967 to 1999 (including the cost of deaths and injuries). A storm surge is an increase in coastal water levels well above the normal high tide. If the storm surge is combined with daily tidal variation, the combined water level is called the storm tide. When the resulting storm tide exceeds the normal tidal range, local beach topography will dictate whether significant coastal inundation will occur.

  • Climate change is expected to increase severe wind hazard in many regions of the Australian continent with consequences for exposed infrastructure and human populations. The objective of this paper is to provide an initial nationally consistent assessment of wind risk under current climate, utilizing the Australian/New Zealand wind loading standard (AS/NZS 1170.2, 2002) as a measure of the hazard. This work is part of the National Wind Risk Assessment (NWRA), which is a collaboration between the Australian Federal Government (Department of Climate Change and Energy Efficiency) and Geoscience Australia. It is aimed at highlighting regions of the Australian continent where there is high wind risk to residential structures under current climate, and where, if hazard increases under climate change, there will be a greater need for adaptation. This assessment is being undertaken by separately considering wind hazard, infrastructure exposure and the wind vulnerability of residential buildings. The NWRA will provide a benchmark measure of wind risk nationally (current climate), underpinned by the National Exposure Information System (NEXIS; developed by Geoscience Australia) and the wind loading standard. The methodology which determines the direct impact of severe wind on Australian communities involves the parallel development of the understanding of wind hazard, residential building exposure and the wind vulnerability of residential structures. We provide the current climate wind risk, expressed as annualized loss, based on the wind loading standard.

  • The Bushfire CRC initiated in 2011 the project 'Fire & Impact Risk Evaluation - Decision Support Tool (F.I.R.E.-D.S.T)' involving Geoscience Australia, CSIRO, Bureau of Meteorology and University of Melbourne. The project is the largest of the Bushfire CRC's suite of projects and conducts research into the multiple aspects required for the computer simulation of bushfire impact and risk on the peri-urban and urban interface. This paper will provide an overview of the research directions for the project and our research progress. In particular we will summarise our progress in: - The development of a Bushfire Risk Assessment Framework, - The inclusion of detailed building information to improve exposure, - The inclusion of human factors and wind damage in determining building vulnerability to bushfires, - The new Bureau of Meteorology ACCESS Numerical Weather Prediction (NWP) system to provide high temporal and spatial resolution meteorology for input into the PHOENIX Rapidfire fire spread simulation model, - The development of very-high resolution local wind modifiers, - The changes made to the PHOENIX fire simulation system, - The development of an bushfire impact/damage subsystem, - The integration of the exposure, vulnerability, fire spread and impact systems to produce a cohesive research tool, and - Initial research on convection column and smoke plume dynamics. The team examined the effectiveness of this research by analysing numerous simulation scenarios. This paper will display the effectiveness of the research progress by providing one example of the comparison between the 2009 Black Saturday

  • AUSTRALIAN MULTI-HAZARD RISK RESEARCH TO INFORM MITIGATION John Schneider, Mark Edwards, Trevor Jones, Bob Cechet, Trevor Dhu, Ole Nielsen, David Robinson, David Burbidge, Jane Sexton, Krishna Nadimpalli Risk & Impact Analysis Group, Geoscience Australia GPO Box 378, Canberra, ACT 2601, Australia, john.schneider@ga.gov.au The annual cost of sudden onset natural hazards in Australia was estimated in 2001 to be more than 1.1 billion Australian dollars, and the cost of events since then indicates that ongoing efforts are required to manage the risks from a range of hazards. Tropical Cyclone Larry which impacted North Queensland (March 2006) and the Hunter Valley floods (June 2007) are the latest events to have each caused more than a billion dollars of insured and uninsured damage. They have also triggered substantial government relief payments. In 2003 the Council of Australian Governments (COAG) published a review of natural disaster relief and mitigation arrangements in Australia. Significantly, the review recommended the development and implementation of a "national program of systematic and rigorous disaster risk assessments". The report advocated a fundamental shift in focus from response to cost-effective, evidence-based disaster mitigation. As a result, the Natural Disaster Mitigation Programme (NDMP) was implemented by the Australian Government in collaboration with the State and Territory Governments. The aim of the NDMP was to reduce the costs of natural disasters in Australia by supporting risk assessment and mitigation efforts. Geoscience Australia has been engaged as a technical advisor as part of the programme and has also undertaken a series of national risk assessments for a range of natural hazards. Geoscience Australia has also facilitated the development of a national risk assessment advisory structure and risk assessment framework. Significant progress has been made in developing methods, models and tools for application to impact and risk assessment studies. In this presentation we examine three risk/impact assessment models and associated case studies for earthquake, cyclone/severe wind and tsunami. Each risk/impact model consists of hazard, building and population exposure, and consequence/damage modules. The hazard component considers the probability of occurrence of events of different magnitudes (or categories) and locations, and the propagation of energy from the hazard source to sites of interest. The exposure information is provided by the National Exposure Information System (NEXIS), which captures key attributes of residential and commercial buildings, critical infrastructure, population statistics, and business activity information. Vulnerability models consider the relationship between hazard exposure and the resulting damage to buildings/infrastructure, and human casualties. Underpinning research has been directed at developing vulnerability models applicable to Australian infrastructure and has drawn upon several surveys of extreme event damage. Building damage is then linked to repair-cost models that have been developed using quantity surveying data. Finally, the costs and repair times are used to evaluate direct and indirect economic impacts at a regional and national scale. The economic assessment has entailed the spatialisation of the disruption of essential utility services to urban communities well outside the footprint of damage. Geoscience Australia is making these risk/impact assessment models and information available to the States and Territories and other stakeholders. This is being done through the release of open source software, interoperable databases, web-based information access, and the training of technical experts.

  • The influence of federalism, especially in the role of fiscal centralisation, has significantly shaped Australia's state and federal government approaches and management of natural disasters. A review of the political climate around the time Cyclone Tracy devastated Darwin in 1974 provides a significant insight into how the relationship between the Commonwelath and State Governments shaped the backbone of Australia's emergency management arrangements. This influence is still evident today and provides an ongoing challenge for achieveing long-term mitigation.

  • Geoscience Australia (GA) is currently undertaking a process of revising the Australian National Earthquake Hazard Map using modern methods and an updated catalogue of Australian earthquakes. This map is a key component of Australia's earthquake loading standard, AS1170.4. Here we present an overview of work being undertaken within the GA Earthquake Hazard Project towards delivery of the next generation earthquake hazard map. Knowledge of the recurrence and magnitude (including maximum magnitude) of historic and pre-historic earthquakes is fundamental to any Probabilistic Seismic Hazard Assessment (PSHA). Palaeoseismological investigation of neotectonic features observed in the Australian landscape has contributed to the development of a Neotectonic Domains model which describes the variation in large intraplate earthquake recurrence behaviour across the country. Analysis of fault data from each domain suggests that maximum magnitude earthquakes of MW 7.0-7.5±0.2 can occur anywhere across the continent. In addition to gathering information on the pre-historic record, more rigorous statistical analyses of the spatial distribution of the historic catalogue are also being undertaken. Earthquake magnitudes in Australian catalogues were determined using disparate magnitude formulae, with many local magnitudes determined using Richter attenuation coefficients prior to about 1990. Consequently, efforts are underway to standardise magnitudes for specific regions and temporal periods, and to convert all earthquakes in the catalogue to moment magnitude. Finally, we will review the general procedure for updating the national earthquake hazard map, including consideration of Australian-specific ground-motion prediction equations. We will also examine the sensitivity of hazard estimates to the assumptions of certain model components in the hazard assessment.

  • An increase in the frequency and intensity of storms, coastal flooding, and spread of disease as a result of projected climate change and sea-level rise is likely to damage built environments and adversely affect a significant proportion of Australia's population. Understanding the assets at risk from climate change hazards is critical to the formulation of adaptation responses and early action is likely to be the most cost effective approach to managing the risk. Understanding the level of exposure of assets, such as buildings, lifeline utilities and infrastructure, under current and future climate projections is fundamental to this process. The National Exposure Information System (NEXIS) is a significant national capacity building task being undertaken by Geoscience Australia (GA). NEXIS is collecting, collating, managing and providing the exposure information required to assess climate change impacts. It provides residential, business and infrastructure exposure information derived from several fundamental datasets. NEXIS is also expanding to include institutions (such educational, health, emergency, government and community buildings) and lifeline support infrastructure exposure. It provides spatial exposure data in GIS format at a building level and is often provided to clients for an area of interest. It is also designed to predict future exposure for climate change impact analysis. NEXIS is currently sourcing more specific datasets from various data custodians including state and local governments along with private data providers. NEXIS has been utilised in various climate change impact projects undertaken by CSIRO, the Department of Climate Change (DCC), the Department of Environment, Water, Heritage and the Arts (DEWHA), and several universities. Examples of these projects will be outlined during the presentation.

  • In order to calibrate earthquake loss models for the U.S. Geological Survey's Prompt Assessment of Global Earthquakes for Response (PAGER) system, two databases have been developed: an Atlas of ShakeMaps and a catalog of human population exposures to moderate to strong ground shaking (EXPO-CAT). The full ShakeMap Atlas currently contains over 5,600 earthquakes from January 1973 through December 2007, with almost 500 of these maps constrained by instrumental ground motions, macroseismic intensity data, community internet intensity observations, and published earthquake rupture models. The catalog of human exposures is derived using current PAGER methodologies. Exposure to discrete levels of shaking intensity is obtained by merging Atlas ShakeMaps with a global population database. Combining this population exposure dataset with historical earthquake loss data provides a useful resource for calibrating loss methodologies against a systematically-derived set of ShakeMap hazard outputs. Two applications of EXPO-CAT are illustrated: i) a simple objective ranking of country vulnerability to earthquakes, and; ii) the influence of time-of-day on earthquake mortality. In general, we observe that countries in similar geographic regions with similar construction practices tend to cluster spatially in terms of relative vulnerability. We find only limited quantitative evidence to suggest that time-of-day is a significant factor in earthquake mortality. Finally, we combine all the Atlas ShakeMaps to produce a global map of the peak ground acceleration (PGA) observed in the past 35 years, and compare this composite ShakeMap with existing global hazard models. In general, these analyses suggest that existing global and regional hazard maps tend to overestimate hazard.

  • The impacts of climate change, including sea level rise and the increased frequency of storm surge events, will adversely affect infrastructure in a significant number of Australian coastal communities. In order to quantify this risk and develop suitable adaptation strategies, the Department of Climate Change and Energy Efficiency (DCCEE) commissioned the National Coastal Vulnerability Assessment (NCVA). With contributions from Geoscience Australia (GA) and the University of Tasmania, this first-pass national assessment has identified the extent and value of infrastructure that are potentially vulnerable to impacts of climate change. A number of fundamental national scale datasets underpinned the NCVA. A mid-resolution digital elevation model was used to model a series of sea level rise projections incorporating 1 in 100 year storm-tide estimates where available. The model outputs were overlain with a national coastal geomorphology dataset, titled the Smartline. The Smartline identified coastal landforms that are potentially unstable and may recede under the influence of rising sea level. These datasets were then overlain with Geoscience Australia's National Exposure Information System (NEXIS) to quantify the number and value of infrastructure elements (including residential and commercial buildings, roads and rail) potentially vulnerable to a range of sea-level rise and recession estimates for the year 2100.

  • We highlight the importance of developing and integrating fundamental information at a range of scales (regional to national to local) to develop consistency, gain ownership, and meet the needs of a range of users and decision makers. We demonstrate this with a couple of case studies where we have leveraged national databases and computational tools to work locally to gain ownership of risks and to develop adaptation options. In this sense we endorse the notion of combining top down and bottom up approaches to get the best outcome.