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  • 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.

  • A comprehensive earthquake impact assessment requires an exposure database with attributes that describe the distribution and vulnerability of buildings in the region of interest. The compilation of such a detailed database will require years to develop for a moderate-sized city, let alone on a national scale. To hasten this database development in the Philippines, a strategy has been employed to involve as many stakeholders/organizations as possible and equip them with a standardized tool for data collection and management. The best organizations to tap are the local government units (LGUs) since they have better knowledge of their respective area of responsibilities and have a greater interest in the use of the database. Such a tool is being developed by PHIVOLCS-DOST and Geoscience Australia. Since there are about 1,495 towns and cities in the country with varying financial capacities, this tool should involve the use of affordable hardware and software. It should work on ordinary hardware, such as an ordinary light laptop or a netbook that can easily be acquired by these LGUs. The hardware can be connected to a GPS and a digital camera to simultaneously capture images of structures and their location. The system uses an open source database system for encoding the building attributes and parameters. A user-friendly GUI with a simplified drop-down menu, containing building classification schema, developed in consultation with local engineers, is utilised in this system. The resulting national database is integrated by PHIVOLCS-DOST and forms part of the Rapid Earthquake Damage Assessment System (REDAS), a hazard simulation tool that is also made available freely to partner local government units.

  • The Australian Government, through the Department of Climate Change and Energy Efficiency, recognises the need for information that allows communities to decide on a strategy for climate change adaptation. A first pass national assessment of vulnerability to Australia's coast identified that considerable sections of the coast could be impacted by sea level rise. This assessment however, did not provide sufficient detail to allow adaptation planning at a local level. Accounting for sea level rise in planning procedures requires knowledge of the future coastline, which is still lacking. Modelling the coastline given sea level rise is complex, however. Erosion will alter the shores in varied ways around Australia's coastline, and extreme events will inundate areas that currently appear to be well above the projected sea level. Moreover, the current planning practice of designating zones with acceptable inundation risk is no longer practical when considering climate change, as this is likely to remain uncertain for some time. Geoscience Australia, with support from the DCCEE, has now conducted a more detailed study for a local area in Western Australia that was identified to be at high risk in the national assessment. The aim of the project was to develop a localised approach so that information could be developed to support adaptation to climate change in planning decisions at the community level. The approach included modelling a historical tropical cyclone and its associated storm surge for a range of sea level rise scenarios. The approach also included a shoreline translation model that forecast changes in coastal sediment transport. Inundation footprints were created and integrated with Geoscience Australia's national exposure information system, NEXIS, to develop impact assessments on building assets, roads and railways. Studies such as this can be a first step towards enabling the planning process to adapt to increased risk.

  • Climate change has become a real challenge for all nations throughout the world. The Fifth IPCC Assessment Report (2007) indicates that climate change is inevitable and those nations that quickly adapt will mitigate risk from the threats of the increased strength of tropical cyclones, storm surge inundation, floods and the spread of disease vectors. Decision making for adaptation will be more effective when it is based on evidence. Evidence-based disaster management means that decision makers are better informed, and the decision making process delivers more rational, representative and objective climate change outcomes. To achieve this, fundamental data needs to be translated into information and knowledge, before it can be put to use by the decision makers as policy, planning and implementation. The exposure to these increased natural hazards includes the communities, businesses, services, lifeline utilities and infrastructure. The thorough understanding of exposed infrastructure and population under current and future climate projections is fundamental to the process of future capacity building. The development of the National Exposure Information System (NEXIS) is a significant national project being undertaken by Geoscience Australia (GA). NEXIS collects, collates, manages and provides the information required to assess multi-hazard impacts. Exposure information is defined as a suite of elements at risk from climate change which includes human populations, buildings, businesses and infrastructure.

  • Stochastic finite-fault ground-motion prediction equations (GMPEs) are developed for the stable continental region of southeastern Australia (SEA). The models are applicable for horizontal-component ground motions for earthquakes 4.0 <= MW <= 7.5 and distances less than 400 km. The models are calibrated with updated source and attenuation parameters derived from SEA ground-motion data. Careful analysis of well-constrained earthquake stress parameters indicates a dependence on hypocentral depth. It is speculated that this is the effect of an increasing crustal stress profile with depth. However, rather than a continuous increase, the change in stress parameter appears to indicate a discrete step near 10 km depth. Average stress parameters for SEA earthquakes shallower and deeper than 10 km are estimated to be 23 MPa and 50 MPa, respectively. These stress parameters are consequently input into the stochastic ground-motion simulations for the development of two discrete GMPEs for shallow and deep events. The GMPEs developed estimate response spectral accelerations comparable to the Atkinson and Boore (BSSA, 2006) GMPE for eastern North America (ENA) at short rupture distances (less than approximately 100 km). However, owing to higher attenuation observed in the SEA crust (Allen and Atkinson, BSSA, 2007), the SEA GMPEs estimate lower ground-motions than ENA models at larger distances. The response spectral models are validated against moderate-magnitude 4.0 <= MW <= 5.3 earthquakes from eastern Australia. Overall the SEA GMPEs show low median residuals across the full range of period and distance. In contrast, Eastern North American models tend to overestimate response spectra at larger distances. Because of these differences, the present analysis justifies the need to develop Australian-specific GMPEs where ground-motion hazard from a distant seismic source may become important.

  • 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

  • Tropical cyclones, thunderstorms and sub-tropical storms can generate extreme winds that can cause significant economic loss. Severe wind is one of the major natural hazards in Australia. The Geoscience Australia's Risk and Impact Analysis Group (RIAG) is developing mathematical models to study a number of natural hazards including wind hazard. In this study, RIAG's wind hazard model for non-cyclonic regions of Australia (Region A in the Australian-New Zealand Wind Loading Standard; AS/NZS 1170.2(2010)) for both current and a range of projected future climate are discussed. The methodology involves a combination of 3 models: - A Statistical Model (ie. a model based on observed data) to quantify wind hazard using extreme value distributions. - A technique to extract and process wind speeds from a high-resolution regional climate model (RCM) which produces gridded hourly 'maximum time-step mean' wind speed and direction fields, and a - Monte Carlo method to generate gust wind speeds from the RCM mean winds. Gust wind speeds are generated by a numerical convolution of the mean wind speed distribution and a regional 'observed' gust factor. Wind hazard at a particular location is affected by the corresponding wind direction. In the last part of this paper a methodology to calculate wind direction multipliers over a region is presented. These multipliers are used to assess the actual wind hazard at the given location. To illustrate the methodology involved with the calculation of severe wind hazard, including the effect of wind direction, analysis over the Australian state of Tasmania will be presented (current and future climate).

  • The Asia-Pacific region is home to well over half the world's population and is also the focus of some of earth's most intense geological activity. It is no surprise therefore that geological hazards, in particular earthquake and volcano hazards, make the Asia-Pacific region the scene of som e of the worlds most lethal natural disasters. While this is evident form a perusal of historical data relating to natural disasters, it is not clear how well such historical data can be used as a guide for high -impact events that might be expected in the future. This uncertainty is due to (1) how poorly extreme geological events having long recurrence intervals are represented in the relatively short historical record, and (2) the failure of the historical record to account for recent demographic trends, in particular the explosive growth of population in the Asia -Pacific region and its rapid urbanisation during the 20 th century. We present here two novel techniques for assessing the potential impacts of volcanic and earthquake events on human population in the Asia Pacific region. For volcanic risk, we have calculated the frequency of large eruptions, aggregated for the countries of the Asia -Pacific region, using data provided by the Smithsonian Institution's Global Volcanism Program. These eruption frequ encies have been combined with an analysis of population data for the region to estimate the average number of people who might be affected, in the broad sense of death, injury or loss of essential services, by a major volcanic eruption. For earthquake, risk, we have considered that the potential future high -impact events will be driven by the probability that an earthquake might occur in or adjacent to one of the many megacities of the Asia -Pacific region. Earthquake probabilities near megacities are cal culated from catalogue data, and these are combined with a rough criterion for damage based on earthquake ground motion, to asses potentially affected populations. We present preliminary results of these analyses, which suggest the potential for earthquakes and volcanoes in the Asia-Pacific region to cause future `mega-disasters', for which affected populations may be much larger than the numbers indicated by the historical record.

  • Effective disaster risk reduction is founded on knowledge of the underlying risk. While methods and tools for assessing risk from specific hazards or to individual assets are generally well developed, our ability to holistically assess risk to a community across a range of hazards and elements at risk remains limited. Developing a holistic view of risk requires interdisciplinary collaboration amongst a wide range of hazard scientists, engineers and social scientists, as well as engagement of a range of stakeholders. This paper explores these challenges and explores some of the common and contrasting issues sampled from a range of applications addressing earthquake, tsunami, volcano, severe wind, flood, and sea-level rise from projects in Australia, Indonesia and the Philippines. Key issues range from the availability of appropriate risk assessment tools and data, to the ability of communities to implement appropriate risk reduction measures. Quantifying risk requires information on the hazard, the exposure and the vulnerability. Often the knowledge of the hazard is reasonably well constrained, but exposure information (e.g., people and their assets) and measures of vulnerability (i.e., susceptibility to injury or damage) are inconsistent or unavailable. In order to fill these gaps, Geoscience Australia has developed computational models and tools which are open and freely available. As the knowledge gaps become smaller, the need is growing to go beyond the quantification of risk to the provision of tools to aid in selecting the most appropriate risk reduction strategies (e.g., evacuation plans, building retrofits, insurance, or land use) to build community resilience.

  • INFORMING NATURAL HAZARD RISK MITIGATION THROUGH A RELIABLE DEFINITION OF EXPOSURE Krishna Nadimpalli, Mark Edwards, Mark Dunford Risk & Impact Analysis Group, Geoscience Australia GPO Box 378, Canberra, ACT 2601, Australia, krishna.nadimpalli@ga.gov.au Fundamental to any risk assessment is an understanding of the infrastructure and people exposed to the hazard under consideration. In Australia there is presently no nationally consistent exposure database that can provide this information. The need to better understand risk was recognised in the report on natural disaster relief and mitigation arrangements made to the Council of Australian Governments (COAG) in 2003. The report included a recommendation to develop and implement a five-year national program of systematic and rigorous disaster risk assessments. In response to this Geoscience Australia (GA) is undertaking a series of national risk assessments for a range of natural hazards. This work is being underpinned by a parallel development of a national definition of community exposure called the National Exposure Information System (NEXIS). The NEXIS aims to provide nationally consistent and best available exposure information at the building level. The building types considered are residential, business (commercial and industrial), and ancillary (educational, government, community, religious, etc.). NEXIS requires detailed spatial analysis and integration of available demographic, structural and statistical data. Fundamentally, this system is being developed from several national spatial datasets as a generic approach with several assumptions made to derive meaningful information. NEXIS is underpinning scenarios and risk assessments for various hazards. Included are earthquakes, cyclones, severe synoptic wind, tsunami, flood and technogenic critical infrastructure failure. The NEXIS architecture is completed and the system currently provides residential exposure information nationally. The prototype for business exposure is well developed and a national definition of business exposure will be generated by June 2008. Ancillary buildings and various critical infrastructure sector exposures will be incorporated into the future. While the present approach is largely generic, more specific building and socio-economic information will be incorporated as new datasets or sources of information become available. Opportunities also exist for NEXIS to be integrated with early warning and alert systems to provide real time assessments of damage or to forecast the impact for a range of hazards. This paper describes the methodologies used by NEXIS and how these will be advanced in the future to provide a more complete and specific definition of exposure to inform severe hazard risk assessment, risk mitigation and post event response.