The Bushfire Attack Level Toolbox provides access to ArcGIS geoprocessing scripts that calculate the Bushfire Attack Level (BAL) as per Method 1 in AS-3959 (2009). BAL is a measure of the severity of a building's potential exposure to ember attack, radiant heat and direct flame contact in the event of a bushfire. It serves as a basis for establishing the requirements for construction to improve protection of building elements from attack by bushfire. The BAL Maps and Exposure report provide maps of three communities in Western Australia, with indicative BAL levels, and the aggregate inventory of assets and population exposed to the different levels of BAL.

The local magnitude ML 5.4 (MW 5.1) Moe earthquake on 19 June 2012 that occurred within the Australian stable continental region was the largest seismic event for the state of Victoria for more than 30 years. Seismic networks in the southeast Australian region yielded many high-quality recordings of the moderate-magnitude earthquake mainshock and its largest aftershock (ML 4.4; MW 4.3) at a hypocentral range of 10 to 480 km. The source and attenuation characteristics of the earthquake sequence are analyzed. Almost 15,000 felt reports were received following the main shock, which tripped a number of coal-fired power generators in the region, amounting to the loss of approximately 1955 megawatts of generation capacity. The attenuation of macroseismic intensities are shown to mimic the attenuation shape of Eastern North America (ENA) models, but require an inter-event bias to reduce predicted intensities. Further instrumental ground-motion recordings are compared to ground-motion models (GMMs) considered applicable for the southeastern Australian (SEA) region. Some GMMs developed for ENA and for SEA provide reasonable estimates of the recorded ground motions of spectral acceleration within epicentral distances of approximately 100 km. The mean weighted of the Next Generation Attenuation-East GMM suite, recently developed for stable ENA, performs relatively poorly for the 2012 Moe earthquake sequence, particularly for short-period accelerations.

Geoscience Australia has produced an Atlas of Australian earthquake scenarios (the Atlas) to support planning and preparedness operations for emergency management agencies. The Atlas provides earthquake scenarios represent realistic “worst-case” events that may impact population centres around Australia. Such scenarios may also support seismic risk assessments for critical infrastructure assets to inform remediation actions that could be taken to improve resilience to rare seismic events in Australia. The Atlas of seismic scenarios uses the underlying science and data of the 2018 National Seismic Hazard Assessment (NSHA18) to identify the magnitudes and epicentre locations of these hypothetical earthquakes. Locations and magnitudes of earthquake scenarios are based upon deaggregation of the NSHA18 hazard model. The USGS ShakeMap software is used to produce ground motion intensity fields with the shaking levels being modified by seismic site conditions mapped at a national scale. Fault sources are incorporated into the Atlas where the magnitude of a given scenario exceeds a threshold magnitude of 6.0 and where the rupture length is likely to be longer than 10 km. If a scenario earthquake is located near a known fault within the Australian Neotectonic Features database, a partial or full-length rupture is modelled along the mapped fault. The Atlas generated two scenarios for each of the160 localities across Australia. The scenarios are based on some of the most likely earthquake magnitude-distance combinations estimated at each site. Output products include shaking contours for a range of intensity measures, including peak acceleration and velocity, as well as response spectral acceleration for 0.3, 1.0 and 3.0 seconds. Also included are raster images and the associated metadata used for generating the scenarios.

The Bushfire Attack Level Toolbox provides access to ArcGIS geoprocessing scripts that calculate the Bushfire Attack Level (BAL) as per Method 1 in AS3959-2009. BAL is a measure of the severity of a building's potential exposure to ember attack, radiant head and direct flame contact. It is defined in AS3959-2009 to serve as a basis for establishing the requirements for construction to improve protection of building elements from attack by bushfire. In the BAL Toolbox, the calculation method (as defined in AS3959-2009) is adapted to be applied spatially. Input information required are a digital elevation model and classified vegetation data. The BAL Toolbox allows users to calculate BAL for small regions, without the need for large computational resources or for executing code in command-line environments. This will provide stakeholders with the ability to efficiently generate rigorous and robust maps of Bushfire Attack Level that adhere to the national standard, compared to products generated by manual techniques. The BAL Toolbox code is written in Python, utilising the ArcGIS "arcpy" module to enable easy reading/writing of raster data and to provide methods for a graphical user interface in the standard ArcGIS tool style. The BAL Toolbox User Guide provides users an overview of the Toolbox, instructions on installation, any customisations execution and evaluation of results.

The TCRM Stochastic Event Catalogue contains artificially generated tropical cyclone tracks and wind fields representing 10000 years of tropical cyclone activity. The catalogue is stored by year, with a track file and wind field file. The wind field file contains the maximum wind speed from all events occuring in the corresponding track file (i.e. it represents annual maximum wind speeds).

In the last few years there have been several probabilistic seismic hazard assessments (PSHA) of Adelaide. The resulting 500 year PGA obtained are 0.059, 0.067, 0.109 and 0.141. The differences between the first three are readily accounted for by choice of GMPE, how faults are included and differences in recurrence estimation, with each of these having a similar level of importance. As no GMPEs exist for the Mt Lofty and Flingers Ranges the choices of GMPEs were all based on geological analogies. The choice of at what weighting to include low attenuation, that is a stable continental crust, GMPE was most important. At a return period of 500 year the inclusion of faults was not necessarily significant. The choice of whether the faults behaved with Characteristic or Gutenberg-Richter recurrence statistics had the highest impact on the hazard with the choice of slip rate the next most important. A low slip rate Characteristic fault, while increasing the hazard for longer return periods (i.e. ~2500 years), results in only a minor increase at 500 years. The magnitude frequency distribution b-value for the four studies were 1.043, 0.88, 0.915 and 0.724. For the same activity in the magnitude range of 3.0 to 3.5, the activity level at M 6.0 is an order of magnitude higher for a b-value of 0.724 compared to a b-value of 1.043. This increase in activity rate of larger earthquakes significantly increases the hazard. The average of the first three studies is 0.078±0.022 (0.056 -0.100) g. This range is reflecting the intrinsic uncertainty in calculating PSHAs where many of the inputs are poorly constrained. The results for the highest hazard level PSHA study (i.e. 0.141g) can be explained by their use of a low b-value (i.e. 0.724). M. Leonard1, R. Hoult2, P. Somerville3, G. Gibson2, D. Sandiford2, H. Goldsworthy2, E. Lumantarna2 and S Spiliopoulos1. 1Geoscience Australia, 2The University of Melbourne, 3 URS

Summary XML files complying with the Australian Flood Study Data Model including one file for each Jurisdiction and on All-in-one file.

Prior to the development of Australian-specific magnitude formulae, the 1935 magnitude corrections by Charles Richter – originally developed for southern California – was almost exclusively used to calculate earthquake magnitudes throughout Australia prior to the 1990s. Due to the difference in ground-motion attenuation between southern California and much of Australia, many historical earthquake magnitudes are likely to be overestimated in the Australian earthquake catalogue. A method has been developed that corrects local magnitudes using the difference between the original (inappropriate) magnitude corrections and the Australian-specific corrections at a distance determined by the nearest recording station likely to have recorded the earthquake. These corrections have reduced the rates of local magnitudes of 4.5 in the historical catalogue by about 30% since 1900, while the number of magnitude 5.0 earthquakes has reduced by about 60% in the same time period. The reduction in the number of moderate-to-large-magnitude earthquakes over the instrumental period yields long-term earthquake rates that are more consistent with present-day rates, since the development of Australian-specific magnitude formulae. The adjustment of historical earthquake magnitudes is important for seismic hazard assessments, which assume a Poisson distribution of earthquakes in space and time.

Wind multipliers are factors that transform wind speeds over open, flat terrain (regional wind speeds) to local wind speeds that consider the effects of direction, terrain (surface roughness), shielding (buildings and structures) and topography (hills and ridges). During the assessment of local wind hazards (spatial significance in the order 10's of metres), wind multipliers allow for regional wind speeds (order 10 to 100's of kilometres) to be factored to provide local wind speeds. <b>Value: </b>The wind multiplier data is used in modelling the impacts (i.e. physical damage) of wind-related events such as tropical cyclones (an input for Tropical Cyclone Risk assessment), thunderstorms and other windstorms. <b>Scope: </b>Includes terrain, shielding and topographic multipliers for national coverage. Each multiplier further contains 8 directions.

Internal advice on tsunami, earthquake and severe wind hazards for the Kavieng Port region, derived from large-scale hazard assessments. This advice (refer TRIM D2021-55554) was provided to the Australia Pacific Climate Partnership (APCP) as part of Geoscience Australia's (GA's) contributions to the program. (In confidence report to APCP, not for distribution)