A probabilistic tsunami hazard assessement (PTHA) was developed for the island of Tongatapu, All modelled tsunamis were initiated by hypothetical thrust earthquakes on the nearby Kermadec-Tonga subduction zone. We provide raster outputs containing the inundation depth with an estimated 10% and 2% chance of being exceeded in 50 years, as well as the code used to perform the analysis [both available here: https://github.com/GeoscienceAustralia/ptha/tree/master/misc/probabilistic_inundation_tonga2020].

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.

<p>Geoscience Australia has recently released its 2018 National Seismic Hazard Assessment (NSHA18). Results from the NSHA18 indicate significantly lower seismic hazard across almost all Australian localities at the 1/500 annual exceedance probability level relative to the factors adopted for the current Australian Standard AS1170.4–2007 (R2018). These new hazard estimates, coupled with larger kp factors, have challenged notions of seismic hazard in Australia in terms of the recurrence of damaging ground motions. As a consequence, the new hazard estimates have raised questions over the appropriateness of the prescribed probability level used in the AS1170.4 to determine appropriate seismic demands for the design of ordinary-use structures. Therefore, it is suggested that the ground-motion exceedance probability used in the current AS1170.4 be reviewed in light of the recent hazard assessment and the expected performance of modern buildings for rarer ground motions. <p>Whilst adjusting the AS1170.4 exceedance probability level would be a major departure from previous earthquake loading standards, it would bring it into line with other international building codes in similar tectonic environments. Additionally, it would offer opportunities to further modernise how seismic demands are considered in Australian building design. In particular, the authors highlight the following additional opportunities: 1) the use of uniform hazard spectra to replace and simplify the spectral shape factors, which do not deliver uniform hazard across all natural periods; 2) updated site amplification factors to ensure continuity with modern ground-motion models, and; 3) the potential to define design ground motions in terms of uniform collapse risk rather than uniform hazard. Estimation of seismic hazard at any location is an uncertain science. However, as our knowledge improves, our estimates of the hazard will converge on the actual – but unknowable – (time independent) hazard. It is therefore prudent to regularly update the estimates of the seismic demands in our building codes using the best available evidence-based methods and models.

The Geological Survey of Canada's 5th Generation seismic hazard model for Canada forms the basis for the seismic design provisions of the 2015 National Building Code of Canada (NBCC). We deaggregate the seismic hazard results for selected cities to help understand the relative contributions of the earthquake sources in terms of distance and magnitude. Deaggregation for a range of probabilities and spectral accelerations (Sa) from 0.2 to 10.0 seconds is performed to examine in detail the hazard for two of Canada's largest urban centres at highest risk, Vancouver in the west and Montréal in the east. A summary table of deaggregated seismic hazard is provided for other selected Canadian cities, for Sa(0.2), Sa(2.0) and peak ground acceleration (PGA) at a probability of exceedence of 2%/50 years. In most cases, as the probability decreases, the hazard sources closer to the site dominate. Larger, more distant earthquakes contribute more significantly to hazard for longer periods than shorter periods. The deaggregations allow better-informed choices of scenario events and for the selection of representative time histories for engineering design.

This dataset provides geospatial representation of the Australian wind regions defined in AS/NZS 1170.2 (2021) Structural Design Actions Part 2: wind actions (hereafter “Standard”). The dataset is intended to assist in delineating areas for referencing the Standard – for example in assigning building vulnerability models across the country. The dataset represents Geoscience Australia's interpretation of the definitions set out in the Standard and is intended for internal use only. This dataset is not suitable for design purposes: professional designers should refer to the Standard for assessing the wind region for their projects. In the event of any inconsistency between this dataset and Figure 3.1 in the Standard, the Standard will take precedence. This product has not been formally endorsed by Standards Australia or the relevant Working Groups and subcommittees. References to localities are indicative and use the best available information at the time of production. For further information on this dataset, please contact hazards@ga.gov.au.

The Geological and Bioregional Assessments (GBA) Program is a series of independent scientific studies undertaken by Geoscience Australia and the CSIRO, supported by the Bureau of Meteorology, and managed by the Department of Agriculture, Water and the Environment. The Program consists of three stages across three regions with potential to deliver gas to the East Coast Gas Market. Stage 1 was a rapid regional prioritisation conducted by Geoscience Australia, to identify those sedimentary basins with the greatest potential to deliver shale and/or tight gas to the East Coast Gas Market within the next five to ten years. This prioritisation process assessed 27 onshore eastern and northern Australian basins with shale and/or tight gas potential. Further screening reduced this to a shortlist of nine basins where exploration was underway. The shortlisted basins were ranked on a number of criteria. The Cooper Basin, the Beetaloo Sub-basin and the Isa Superbasin were selected for more detailed assessment. Stage 2 of the program involved establishing a baseline understanding of the identified regions. Geoscience Australia produced regional geological evaluations and conceptualisations that inform the assessment of shale and/or tight gas prospectivity, ground- and surface-water impacts, and hydraulic fracturing models. Geoscience Australia’s relative prospectivity assessments provide an indication of where viable petroleum plays are most likely to be present. These data indicate areal and stratigraphic constraints that support the program’s further work in Stage 3, on understanding likely development scenarios, impact assessments, and causal pathways. <b>Citation:</b> Hall Lisa S., Orr Meredith L., Lech Megan E., Lewis Steven, Bailey Adam H. E., Owens Ryan, Bradshaw Barry E., Bernardel George (2021) Geological and Bioregional Assessments: assessing the prospectivity for tight, shale and deep-coal resources in the Cooper Basin, Beetaloo Subbasin and Isa Superbasin. <i>The APPEA Journal</i><b> 61</b>, 477-484. https://doi.org/10.1071/AJ20035

This dataset contains a collection of ESRI geodatabases that hold hazard and impact data derived as part of the Severe Wind Hazard Assessment for Western Australia (2017-2020) project. There are separate geodatabases for each community examined in the project. Within each community, multiple TC scenarios were analysed for each community. The list of scenarios is included below. Geodatabase structure --------------------- Within each geodatabase, the data is structured as set out below. The structure is repeated for each available scenario in that community. Note scenario id numbers have the hyphen ('-') removed in the <scenario id> string below. - Shapefiles |-- TCs within 50 km |-- Cat<X> <scenario id>_Impact [Polygon shape file of SA1-level mean damage state for residential housing] |-- Cat<X> <scenario id>_regionalwind [Polygon shape file of categorised regional wind speed] |-- Cat<X> <scenario id>_track_line [Line shape file of scenario track line segments] |-- Cat<X> <scenario id>_track_point [Point shape file of scenario track points] - Cat<X>_<scenario id>_localwind [Raster format local wind data] Scenarios --------- Scenairo Id number, TC intensity, Location 000-01322,3,Exmouth 013-00928,3,Exmouth 000-06481,5,Exmouth 003-03693,3,PortHedland 000-08534,5,PortHedland 012-06287,3,Broome 012-03435,5,Broome 006-00850,3,Karratha-Roebourne 009-07603,5,Karratha-Roebourne 011-01345,1,Carnarvon 003-05947,3,Carnarvon 011-02754,1,Geraldton 001-08611,3,Geraldton 007-05186,1,Perth bsh291978,1,Perth

Earthquake design standards seek to ensure that structures are adequately resilient to local hazard. The probabilistic hazard that forms the basis of the design loadings used and the methods by which they are calculated typically reflect the best available information and practices at the time. This was the case with the earthquake loadings standard for the design of PNG buildings that was published in 1982. However, with the collaborative development of a better understanding of earthquake hazard across PNG the need to adjust the earthquake loadings for design through an Interim Amendment was highlighted. This key step would precede any more general and broader update of national building regulations. In this paper the process taken to translate the latest earthquake hazard assessment for PNG, PSHA19, to design practice is described. This included an assessment of the level of current under-design and the engagement with stakeholders in PNG to assess their needs through workshop activity. The central document to this process, “The Interim Amendment to PNGS 1001-1982: Part 4: Earthquake Design Actions”, is described and goes beyond the incorporation of the new design hazard to the introduction of new approaches for assessing earthquake loads that more closely align with those used in New Zealand and Australia. Preparation and delivery of seminars in-country to familiarise design professionals with its use are also described along with the series of professional development video products also developed for use in PNG. Finally, future needs in regulatory development in PNG are outlined. Presented at the 2023 Australian Earthquake Engineering Society (AEES) National Conference

Geoscience Australia is currently drafting a new National Earthquake Hazard Map of Australia using modern methods and models. Among other applications, the map is a key component of Australia's earthquake loading code AS1170.4. In this paper we provide a brief history of national earthquake hazard maps in Australia, with a focus on the map used in AS1170.4, and provide an overview of the proposed changes for the new map. The revision takes advantage of the significant improvements in both the data sets and models used for earthquake hazard assessment in Australia since the original maps were 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 - 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 The following papers in this session will address in more detail the changes to the earthquake catalogue, earthquake recurrence and ground motion prediction equations proposed for use in the draft map. The draft hazard maps themselves are presented in the final paper.

Manila is one of the world's megacities, and the Greater Metro Manila Area is prone to natural disasters. These events may have devestating 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.