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  • Crucial elements for assessing earthquake risk are exposure and vulnerability. In assessing earthquake risk to the Australian built environment we need to know what is exposed to earthquake ground motion and also how vulnerable the exposed infrastructure is to the severity of shaking. While central business district (CBD) buildings make up a relatively small proportion of Australia's built environment their function and the business activity they support is vital to Australia's economy. This paper describes an ongoing effort by the Australian Government to undertake engineering and architectural surveys of buildings within state capital CBDs. With funding from the Attorney-General's Department Geoscience Australia has recently completed a survey of the Melbourne CBD and will complete surveys of the Sydney, Adelaide and Brisbane CBDs this financial year. Survey teams comprise a structural engineer and a GIS operator who populates survey fields on a handheld computer. Approximately 90 survey data fields are incorporated in the template to enable capture of the variety in building features. The fields cover building characteristics that are understood to influence earthquake vulnerability. A summary of the survey activity undertaken to date is presented here along with some examples of the type of data that is being collected.

  • Bob Cechet, Mark Edwards and John Holmes (2006) Severe wind hazard/vulnerability modelling workshop,Geoscience Australia, Canberra, December 1st 2005. Proceedings of the 12th AWES Wind Engineering Workshop, Queenstown, New Zealand, February 2nd & 3rd, 4pp

  • This presentation will provide an overview of some of the work currently being undertaken at Geoscience Australia GA) as part of the National Coastal Vulnerability Assessment (NCVA), funded by the Department of Climate Change (DCC). The presentation will summarise the methodology applied, and highlight the issues, including the limitations and data gaps.

  • 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.

  • We report on an assessment of severe wind hazard across the Australian continent, and severe wind risk (quantified in annualised losses due to severe wind damage) in built up areas, based on innovative modelling techniques and application of the National Exposure Information System (NEXIS). A combination of tropical cyclone, synoptic and thunderstorm wind hazard estimates is used to provide a revised estimate of the severe wind hazard across Australia. The hazard modelling techniques developed in this assessment utilise both 'current-climate' and also simulations forced by IPCC SRES climate change scenarios, which have been employed to determine how the wind hazard will be influenced by climate change. We have also undertaken a national assessment of localised wind speed modifiers including topography, terrain and built environment. It is important to account for these effects in assessment of risk as it is the local wind speed that causes damage to structures. The effects of the wind speed modifiers are incorporated through a statistical modification of the regional wind speed. The results from this current climate hazard assessment are compared with the hazard based on the existing understanding as specified in the Australian/New Zealand Wind Loading Standard (AS/NZS 1170.2, 2002). Regions are mapped where the design wind speed depicted in AS/NZS 1170.2 is significantly lower than 'new' hazard analysis. These are regions requiring more immediate attention regarding the development of adaptation options including consideration by the wind loading standards committee for detailed study in the context of the minimum design standards in the current building code regulations. Considering future climate scenarios, the Tasmanian region is used to illustrate where the wind loading standard becomes inadequate, and where retrofitting is indicated as a viable adaptation option at a specified future time. The cost/benefit analysis techniques used will be demonstrated.

  • The coastal zone is arguably the most difficult geographical region to capture as data because of its dynamic nature. Yet, coastal geomorphology is fundamental data required in studies of the potential impacts of climate change. Anthropogenic and natural structural features are commonly mapped individually, with their inherent specific purposes and constraints, and subsequently overlain to provide map products. This coastal geomorphic mapping project centered on a major coastal metropolitan area between Lake Illawarra and Newcastle, NSW, has in contrast classified both anthropogenic and natural geomorphological features within the one dataset to improve inundation modelling. Desktop mapping was undertaken using the Australian National Coastal Geomorphic (Polygon) Classification being developed by Geoscience Australia and supported by the Department of Climate Change. Polygons were identified from 50cm and 1m aerial imagery. These data were utilized in parallel with previous maps including for example 1:25K Quaternary surface geology, acid sulphate soil risk maps as well as 1:100K bedrock geology polygon maps. Polygons were created to capture data from the inner shelf/subtidal zone to the 10 m contour and include fluvial environments because of the probability of marine inundation of freshwater zones. Field validation was done as each desktop mapping section was near completion. This map has innovatively incorporated anthropogenic structures as geomorphological features because we are concerned with the present and future geomorphic function rather than the past. Upon completion it will form part of the National Coastal Geomorphic Map of Australia, also being developed by Geoscience Australia and utilized in conjunction with Smartline.

  • Climate change is a challenge facing nations worldwide. The Fifth IPCC Assessment Report (2007) indicated that climate change is inevitable and that nations need to quickly adapt to mitigate its effects on the risks associated with increased tropical cyclone intensity, storm surge inundation, floods and exacerbated spread of disease. Nationally consistent exposure information is required to understand the risks associated with climate change and thereby support decision making on adaptation options. Decision makers can draw on this evidence-base to develop more rational, representative and objective strategies for addressing emerging challenges. Exposure information requires the translation of fundamental data into information and knowledge before it can be put to use for policy, planning and implementation. Communities, businesses, essential services and infrastructure are all exposed to these increased natural hazards. A thorough understanding of exposed infrastructure, building stock and population under current and future climate projections is fundamental to the process of future capacity building. The National Exposure Information System (NEXIS) provides a broad range of information on the exposure profile of any given area at various administrative and disaster sensitive geographic resolutions with Australia-wide coverage. The information is collected, collated and maintained at building level that can subsequently be aggregated geographically. The information recorded in NEXIS covers a wide range of building attributes such as building type, construction type and year built together with information on population demographics and metrics on business activity such as business type, turnover, employee numbers and customer capacity.

  • Hydrometeorological events make up or contribute to a majority of disasters in Australia and around the world. Scientists expect climate change will accelerate the frequency and intensity of these events in the future. Information on the location and characteristics of the built and social environment combined with hazard modelling and spatial analysis can facilitate the identification of buildings, people and infrastructure exposed to a particular natural hazard event. This information informs evidence based decision making and future planning to aid in the preparedness, response and recovery to severe hazard events. In Australia, the National Exposure Information System (NEXIS) is a significant national project being undertaken by Geoscience Australia (GA). In 2006 GA embarked on the development of NEXIS in response to the Council of Australian Governments (COAG) reform commitment on Australian's ability to manage natural disasters and other emergencies. The COAG commitment called for the establishment of a 'nationally consistent system of data collection, research and analysis to ensure a sound knowledge base on natural disasters and disaster mitigation' (DOTARS 2002). NEXIS database contains information on buildings, people, businesses and infrastructure and is derived from publicly available demographic, structural, economic and statistical data. Exposure profiles contain information on: building type, size, construction materials, age, replacement costs and population demographics for all residential, commercial and industrial buildings in Australia. Aggregated exposure information underpins risk assessment, emergency management, climate change adaptation, urban planning, insurance industry and research to help assist evidence based decision making. NEXIS development and operationalisation is crucial to support the decision makers and underpins community safety, emergency management and disaster risk reduction initiatives Australia This paper will discuss the development of NEXIS and its application in several national projects with the Department of Climate Change Energy and Efficiency (DCCEE) in Australia and recent national disaster impacts assessments on: Queensland tropical cyclone Yasi, Victoria bushfires and the Queensland floods.

  • 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.