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  • 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.

  • The impacts of climate change on sea level rise (SLR) will adversely affect infrastructure in a significant number of Australian coastal communities. A first-pass national assessment has identified the extent and value of infrastructure potentially exposed to impacts from future climate by utilizing a number of fundamental national scale datasets. A mid-resolution digital elevation model was used to model a series of SLR projections incorporating 100 year return-period storm-tide estimates where available (maximum tidal range otherwise). The modeled inundation zones were overlaid with a national coastal geomorphology dataset, titled the Smartline, which identified coastal landforms that are potentially unstable 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 coastal recession estimates for the year 2100. In addition, we examined the changes in exposure under a range of future Australian Bureau of Statistics population scenarios. We found that over 270,000 residential buildings are potentially vulnerable to the combined impacts of inundation and recession by 2100 (replacement value of approximately $A72 billion). Nearly 250,000 residential buildings were found to be potentially vulnerable to inundation only ($A64 billion). Queensland and New South Wales have the largest vulnerability considering both value of infrastructure and the number of buildings affected. Nationally, approximately 33,000 km of road and 1,500 km of rail infrastructure are potentially at risk by 2100.

  • In 2008, the Australian Parliament debated and passed the first national legislation to establish a title system of access and property rights for greenhouse gas (CO2) storage in offshore waters - the Offshore Petroleum and Greenhouse Gas Storage Act 2006 (the Act). The Act provides for petroleum titles and greenhouse gas storage titles to coexist. To manage possible interactions between petroleum and CO2 storage operations, the Act introduced a test to determine whether activities under one title would pose a significant risk of a significant adverse impact (SROSAI test) on pre-existing rights and assets under the other title. Where petroleum and CO2 storage projects are proposed in the same area, the Act provides for commercial agreements between petroleum and CO2 storage proponents. It is only in the absence of any such commercial agreements that the regulator will have to decide whether an activity under one title would pose a significant risk of a significant adverse impact on the operations within the other title area. The SROSAI test is based on three core parameters: - the probability of the occurrence of an adverse impact; - the cost of the adverse impact on the project; and - the total resource value of the project. In estimating the cost of an adverse impact the regulator will take into consideration whether the adverse impact will result in: - any increase in capital or operating costs; - any reduction in rate of recovery of petroleum or rate of injection of CO2; - any reduction in the quantity of the petroleum to be recovered or CO2 stored. Safety and environmental impacts would be considered in estimating costs, only if those impacts would contribute to an increase in capital or operating costs, or reduction in petroleum recovery or CO2 injection. Etc

  • The National Exposure Information System (NEXIS) project is an initiative of Geoscience Australia in response to the Australian Government's research priority of safeguarding Australian communities from natural hazards, critical infrastructure failures and policy development. The governmental priority urges the implementation of a 'nationally consistent system of data collection, research and analysis to ensure a sound knowledge-base on natural disasters and disaster mitigation'. The infrastructure exposure definition and development framework suitable for multi hazards and climate change impact analysis is highly complex. NEXIS aims to meet the challenge by collecting, collating and maintaining nationally consistent exposure information at the individual building level. This requires detailed spatial analysis and the integration of available demographic, structural and statistical data for various sectors. The system integrates data from several national spatial databases, such as the Geocoded National Address File, the Property Cadastre, Australian Bureau of Statistics (ABS) census data, and building data from Australian state governments. It also includes post disaster survey information and data from several infrastructure agencies and local government bodies. NEXIS provides a representative assessment of asset exposure to several hazard models which can be aggregated to an appropriate level from State to mesh block level for the required application. By integrating the information with the decision-support tools of alert systems and early warning, it can enable the rapid forecasting of the impacts due to various hazards (infrastructure damage and casualties). Currently it is being used for tactical response for emergency managers and strategic policy and planning development. In addition to enabling research in Geoscience Australia's risk and impact analysis projects, it supports several government initiatives across the departments and national committees.

  • A model to assess severe wind hazard using climate-simulated wind speeds has been recently completed at Geoscience Australia. The model can calculate return period of wind speeds over a given region considering current as well as future climate conditions. The winds extracted from the climate simulations are winds at 10m height over open terrain. In hazard studies it is important however, to refer the wind speeds to the characteristics of the given location in order to calculate the actual severe wind hazard at the regional level. This is achieved by multiplying the generic wind hazard by a number of wind multipliers. One of those multipliers is wind direction. The wind direction multiplier recognises the prevailing direction of the strongest winds and affects the wind hazard accordingly. Lower wind hazard would correspond to the direction of low wind speeds. In practical applications engineers calculate the wind load in structures by multiplying the design wind speeds recommended by the Australian/NZ standards for wind loading in structures (AS/NZS 1170.2:2010) by some generic multipliers also given in the standards. The multipliers have been developed considering a number of Bureau of Meteorology (BoM) weather recording stations at particular locations in Australia; this method cannot capture the actual regional characteristics in such a vast country like Australia. In this paper we propose a new methodology for calculation of wind direction multipliers based on wind speeds and direction extracted from climate simulations. Our method allows a more realistic assessment of the wind direction multiplier at a particular region.

  • 11-5413 The Probabilistic Volcanic Ash - Hazard Map movie describes how you construct a probabilistic hazard map for volcanic ash, using an example scenario from GA's volcanic ash modelling work in West Java, Indonesia. The target audience is other govt. agencies both national and international, and the general public. The 3.3 minute movie uses 3D Max animations and 2D affects, has narration and production music. The narration will also be done in Bahasa Indonesian, at a later date.

  • 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.

  • Full Version - shows orthographic and fly-through sequence for each of 5 scenarios with a combined max. inundation outline fly-through at end. Description. - Tropical Cyclone Alby passed close to the southwest corner of West Australia on April 4th 1978. Large waves and a storm surge generated by the northerly winds caused substantial coastal erosion along the Lower West coast particularly in the Geographe Bay area. Low-lying areas at Bunbury and Busselton were flooded, forcing the evacuation of many homes including the Bunbury Nursing Home. An approximate 1.1 m storm surge at Busselton caused the tide to peak at 2.5 m about 1 m above the highest astronomical tide. The Busselton Jetty was severely damaged. At Fremantle the surge was about 0.6 m causing a high tide of 1.8 m, about 0.5 m above the highest astronomical tide. [From BOM - http://www.bom.gov.au/weather/wa/cyclone/about/perth/alby.shtml - Retrieved 21/01/2010] This movie displays the results of a number of simulated storm surge events caused by an equivalent storm to Tropical Cyclone Alby on the current built terrain of Mandurah, and projected 2100 coastline with 0.5, 0.8 and 1.1m rises in sea level. Scenario A TC Alby equivalent at current sea level Scenario B Worst case TC Alby equivalent with current sea level Scenario C Worst case TC Alby equivalent in 2100 with 0.5m sea level rise Scenario D Worst case TC Alby equivalent in 2100 with 0.8m sea level rise Scenario E Worst case TC Alby equivalent in 2100 with 1.1m sea level rise

  • This is a short and informative 3.3 minute movie for the Engineering, Economics and Exposure Project - NEXIS Development for DCCEE - late 2010. It is a promotional movie that demonstrates NEXIS capabilities, and explains how NEXIS will be benefitial to the NEXIS stakeholder. This movie may also go onto the web, where it's purpose is to convince the public that NEXIS is a worthwhile investment in Australia's future.

  • Climate change is expected to exacerbate a range of natural hazards in Australia leading to more severe community impacts in the future. There is a need to adapt to a changing hazard environment and increasing community exposure in regions most likely influenced by climate change. Through this paper GA develops a methodology for projecting Australian communities in a spatial sense into the future. The application of this methodology is demonstrated in a case study. In order to address the fact that the impacts of climate change are expected to be more evident in the second half of this century, this model was to extend beyond the 30 year limitation of finer scale population projections, dwelling projections and development plans.