From 1 - 10 / 34
  • This metadata relates to the ANUGA hydrodynamic modelling results for Busselton, south-west Western Australia. The results consist of inundation extent and peak momentum gridded spatial data for each of the ten modelling scenarios. The scenarios are based on Tropical Cyclone (TC) Alby that impacted Western Australia in 1978 and the combination of TC Alby with a track and time shift, sea-level rise and riverine flood scenarios. The inundation extent defines grid cells that were identified as wet within each of the modelling scenarios. The momentum results define the maximum momentum value recorded for each inundated grid cell within each modelling scenario. Refer to the professional opinion (Coastal inundation modelling for Busselton, Western Australia, under current and future climate) for details of the project.

  • 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.

  • 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.

  • This paper presents a model to assess bushfire hazard in south-eastern Australia. The model utilises climate model simulations instead of observational data. Bushfire hazard is assessed by calculating return periods of the McArthur Forest Fires Danger Index (FFDI). The return periods of the FFDI are calculated by fitting an extreme value distribution to the tail of the FFDI data. The results have been compared against a spatial distribution of bushfire hazard obtained by interpolation of FFDI calculated at a number of recording stations in Australia. The results show that climate simulations produce a similar pattern of bushfire hazard than the interpolated observations but the simulated values tend to be up to 60% lower than the observations. This study shows that the major source of error in the simulations is the values of wind speed. Observational wind speed is recorded at a point-based station whilst climate simulated wind speed is averaged over a grid cell. On the other hand FFDI calculation is very sensitive to wind speed and hence to improve the calculation of FFDI using climate simulations it is necessary to correct the bias observed in the simulations. A statistically-based procedure to correct the simulation bias has been developed in this project. Bias-corrected calculation of FFDI shows that the major bushfire hazard in south-eastern Australia is in the western parts of SA and NSW; and in south-western Tasmania.

  • Coastal communities in Australia are particularly exposed to disasters resulting from the coincidence of severe wind damage, storm surge, coastal flooding and shoreline erosion during cyclones and extra-tropical storms. Because the climatic drivers of these events are stronger during or across specific years (e.g. during La Nina periods), they can repeatedly impact the coast over periods of weeks, months or up to a few years. The consequences of individual events are therefore exacerbated with little or no opportunity for recovery of natural systems or communities. This poster summarises the objectives, approach and methodology for this storm surge project. A contribution to the Bushfire and Natural Hazards CRC.

  • This document presents a new set of earthquake hazard maps for consideration in the next revision of the earthquake loading code AS1170.4 "Structural design actions: Part 4 Earthquake actions in Australia". The earthquake catalogue used here includes events up until 2011. It is a combined version of several catalogues provided by external agencies. This represents the most complete catalogue of earthquakes compiled for Australia. The catalogue is more consistent through conversion of various magnitude measurements into a 'pseudo ML' scale. A systematic logic is used to select preferred magnitude types. Aftershocks, foreshocks and mine blasts have been identified and the declustered catalogue used here is cleaner than any previous Australian catalogue. Earthquake source zones applied in the hazard map use a unique combination of three different layers, which capture seismic characteristics at sub-national, regional and high-activity point scales. The map is one of the first in the world to apply a semi-quantitative measure of Mmax for majority of the source zones in the map. We apply recently developed ground motion prediction equations based on modern methods and data. These equations were used to calculate the ground motion at a range of response spectral accelerations, rather than just calculating the hazard for peak ground acceleration (PGA). A suite of maps is calculated using GA's Earthquake Risk Model (EQRM). The EQRM is open-source, allowing the results to be tested or modified independently. The final 2012 Australian earthquake hazard maps for a range of return periods and response spectral periods are presented herein.

  • Stochastic finite-fault ground-motion prediction equations (GMPEs) are developed for the stable continental region of southeastern Australia (SEA). The models are based on reinterpreted source and attenuation parameters for small-to-moderate magnitude local earthquakes and a dataset augmented with ground-motion records from recent significant earthquakes. The models are applicable to horizontal-component ground-motions for earthquakes 4.0 <= MW <= 7.5 and at 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 (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, 2007), the SEA GMPEs estimate lower ground-motions than ENA models at larger distances. A correlation between measured VS30 and ?0 was developed from the limited data available to determine the average site condition to which the GMPEs are applicable. Assuming the correlation holds, a VS30 of approximately 820 m/s is obtained assuming an average path-independent diminution term ?0 of 0.006 s from SEA seismic stations. Consequently, the GMPE presented herein can be assumed to be appropriate for rock sites of B to BC site class in the National Earthquake Hazards Reduction Program (NEHRP, 2003) site classification scheme. 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, ENA 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.

  • 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.

  • A short film about a scientific project aimed at enhancing risk analysis capacities for flood, severe wind from tropical cyclones and earthquake in the Greater Metropolitan Manila Area. Manila is one of the world's megacities, and the Greater Metro Manila Area is prone to natural disasters. These events may have devastating consequences for individuals, communities, buildings, infrastructure and economic development. Understanding the risk is essential for implementing Disaster Risk Reduction programs. In partnership with AusAID, Geoscience Australia is providing technical leadership for risk analysis projects in the Asia-Pacific Region. In the Philippines, Geoscience Australia is engaging with Government of the Philippines agencies to deliver the "Enhancing Risk Analysis Capacities for Flood, Tropical Cyclone Severe Wind and Earthquake in the Greater Metro Manila Area" Project.

  • A community Safety Capbility Flyer was produced to showcase the work undertaken in the Community Safety Value Stream. The flyer includes an introduction to the Community Safety Value Stream, case studies of the work Geoscience Australia does in this space and information on how to engage with Geoscience Australia via the products, tools, models and applications that are produced. This flyer is intended for use a conferences and where promotional material would beneficial to showcase the work undertaken at Geoscience Australia such as the Floodplain Management Association Conference on 19-22 May 2015.