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  • A multi-hazard and exposure analysis of Asia. A GIS study that incorporates regional data for: landslide, tsunami, earthquake, tropical cyclone, volcanic, drought and flood hazard.

  • Geoscience Australia has recently released the 2012 version of the National Earthquake Hazard Map of Australia. Among other applications, the map is a key component of Australia's earthquake loading code AS1170.4. In this presentation we provide an overview of the new maps and how they were developed. The maps take advantage of significant improvements in both the data sets and models used for earthquake hazard assessment in Australia since the map currently in AS1170.4-2007 was produced. These include: - An additional 20+ years of earthquake observations - Improved methods of declustering earthquake catalogues and calculating earthquake recurrence - Ground motion prediction equations (i.e. attenuation equations) based on observed strong motions instead of intensity - Revised earthquake source zones implementing a multi-layer model - Improved maximum magnitude earthquake estimates based on palaeoseismology - The use of open source software for undertaking probabilistic seismic hazard assessment, which promotes testability and repeatability Hazard curves are presented for a range of response spectral acceleration (RSA) periods between 0.0 and 1.0 s and for return periods between a few hundred to a few thousand years. These curves and maps are compared with the current earthquake hazard values in AS1170.4-2007. For a return period of 500 years, the hazard values in the 0.0 s RSA period map are generally lower or the same as the hazard factor values in the AS1170.4 map. This is also true for most of the other RSA periods up to 1.0s for the cities in Australia with Darwin being the main exception. By contrast, the hazard for return periods above 1000 years is higher than the values derived from the tables in AS1170.4 for all RSA periods.

  • Tropical cyclone return period wind hazard layers developed using the Tropical Cyclone Risk Model. The hazard layers are derived from a catalogue of synthetic tropical cyclone events representing 10000 years of activity. Annual maxima are evaluated from the catalogue and used to fit a generalised extreme value distribution at each grid point.

  • The Flood Study Summary Services support discovery and retrieval of flood hazard information. The services return metadata and data for flood studies and flood inundation maps held in the 'Australian Flood Studies Database'. The same information is available through a user interface at http://www.ga.gov.au/flood-study-web/. A 'flood study' is a comprehensive technical investigation of flood behaviour. It defines the nature and extent flood hazard across the floodplain by providing information on the extent, level and velocity of floodwaters and on the distribution of flood flows. Flood studies are typically commissioned by government, and conducted by experts from specialist engineering firms or government agencies. Key outputs from flood studies include detailed reports, and maps showing inundation, depth, velocity and hazard for events of various likelihoods. The services are deliverables fom the National Flood Risk Information Project. The main aim of the project is to make flood risk information accessible from a central location. Geoscience Australia will facilitate this through the development of the National Flood Risk Information Portal. Over the four years the project will launch a new phase of the portal prior to the commencement of each annual disaster season. Each phase will increase the amount of flood risk information that is publicly accessible and increase stakeholder capability in the production and use of flood risk information. flood-study-search returns summary layers and links to rich metadata about flood maps and the studies that produced them. flood-study-map returns layers for individual flood inundation maps. Typically a single layer shows the flood inundation for a particular likelihood or historical event in a flood study area. To retrieve flood inundation maps from these services, we recommend: 1. querying flood-study-search to obtain flood inundation map URIs, then 2. using the flood inundation map URIs to retrieve maps separately from flood-study-map. The ownership of each flood study remains with the commissioning organisation and/or author as indicated with each study, and users of the database should refer to the reports themselves to determine any constraints in their usage.

  • This document describes a structure for exchanging information to assist discovery and retrieval/transfer of flood information, including GIS flood mapping data. The draft class model represents metadata, data and summary information that supports the goals of the National Flood Risk Information Project (NFRIP) to improve the quality, consistency and accessibility of flood information. This document describes the data model that will be used to create an application schema.

  • Tropical Cyclone (TC) Yasi crossed Queensland's Cassowary Coast during the night of the 2nd and 3rd of February, 2011. The cyclone was forecast by BoM (2011) to be a severe storm with wind gusts forecast to exceed the design gust wind speeds for houses set out in AS4055. Following the passage of the cyclone, it was evident that the severe wind and large coastal storm surge had caused significant damage to the region's building stock. Geoscience Australia (GA), together with collaborators from the National Institute of Water and Atmospheric Research, New Zealand (NIWA), Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) and Maddocks & Associates, undertook a survey of damage to the region's buildings caused by severe wind and storm surge.

  • Developing a framework and computational methodology for evaluating the impacts and risks of extreme fire events on regional and peri-urban populations (infrastructure and people) applicable to the Australian region. The research considers three case studies of recent extreme fires employing an ensemble approach (sensitivity analysis) which varies the meteorology, vegetation and ignition in an effort to estimate fire risk to the case-study fire area and adjacent region.

  • On 23 March 2012, at 09:25 UTC, an Mw 5.4 earthquake occurred in the eastern Musgrave Ranges of north-central South Australia, near the community of Ernabella (Pukatja). Several small communities in this remote part of central Australia reported the tremor, but there were no reports of injury or significant damage. This was the largest earthquake recorded on mainland Australia in the past 15 years and resulted in the formation of a 1.6 km long surface deformation zone that included reverse-fault scarps with a maximum vertical displacement of more than 0.5 m, extensive ground cracking, and numerous rock falls. The earthquake occurred in non-extended stable continental region (SCR) cratonic crust, more than 1900 km from the nearest plate boundary. Surface deformation from the Ernabella earthquake provides additional constraint on relations of surface-rupture length to earthquake magnitude. Such relations aid in interpreting Australia’s rich record of prehistoric seismicity and contribute to improved estimates of SCR seismic hazard worldwide. Based upon an analysis of new and reinterpretation of existing surface-rupture length data, faults in non-extended stable cratonic Australia appear to produce longer surface ruptures (for earthquakes larger than Mw ∼ 6:5) than rupture lengths estimated using existing moment-to rupture length scaling relations. The implication is that the estimated maximum, or characteristic, magnitude of paleoearthquakes in such settings may be overestimated where the estimate is based only on the length of the prehistoric fault scarp.

  • Interactive Maps is a discovery and exploration view of Geoscience Australia's geospatial services. The following scientific and decision support themes have curated content comprised of maps and functions. Each map has queries and functions with linked access to OGC (Open Geospatial Consortium) web services and metadata. This system replaces MapConnect and AMSIS applications.

  • On 23 March 2012, at 09:25 GMT, a MW 5.4 earthquake occurred in the eastern Musgrave Ranges region of north-central South Australia, near the community of Ernabella (Pukatja). This was the largest earthquake to be recorded on mainland Australia for the past 15 years and resulted in the formation of a 1.6 km-long surface deformation zone comprising reverse fault scarps with a maximum vertical displacement of over 50 cm, and extensive ground cracking. Numerous small communities in this remote part of central Australia reported the tremor, but there were no reports of injury or significant damage. The maximum ground shaking is estimated to have been in the order of MMI VI. The earthquake occurred in Stable Continental Region (SCR) crust, over 1900 km from the nearest plate boundary. Fewer than fifteen historic earthquakes worldwide are documented to have produced coseismic surface deformation (i.e. faulting or folding) in the SCR setting. The record of surface deformation relating to the Ernabella earthquake therefore provides an important constraint on models relating surface rupture length to earthquake magnitude. Such models may be employed to better interpret Australia's rich prehistoric record of seismicity, thereby improving estimates of seismic hazard.