<div>South East Queensland (SEQ) is exposed to a range of severe storms that generate damaging winds, including east coast lows, thunderstorms and tropical cyclones. The risk posed by these storms is not well understood and, in a region that hosts a large proportion of Queensland’s population and economic activity, it is important to understand these risks and the potential benefits of mitigation actions, particularly in the context of climate change, urban planning and the socio-economic status of the population. &nbsp;</div><div>The primary objectives of the Severe Wind Hazard Assessment for South East Queensland (SWHA-SEQ) project (October 2020 – December 2022) were to improve the understanding of current wind risk in SEQ and to develop actionable information to inform future strategies to reduce this risk. Collaboration across fifteen partners in local government, insurance, emergency management, State government and academia has delivered valuable and actionable insights into the risk and resilience of SEQ at a local scale. </div><div> We discuss the relative contributions of different wind storms to the hazard profile, local influences on hazard and risk, and the intersection with community resilience indicators that assist in formulating targeted mitigation strategies. SEQ has a range of landscapes that influence the local hazard, including heavily urbanized lands, semi-rural communities in complex terrain and beachfront or canal estates. These landscapes, and the attributes of the buildings in them, contribute to the risk profile in varied and complex ways. We also explore the intersection of high-risk areas with socio-economic status to identify priority areas for potential retrofit programs. Presented at the 30th Conference of the Australian Meteorological and Oceanographic Society (AMOS) 2024

<div>The region of coastal South East Queensland (SEQ) is a large concentration of population, industry, and infrastructure important to the economy of Queensland and of Australia. The region is also subject to severe storms that generate damaging winds, particularly as result of thunderstorm and tropical cyclone activity. Older residential housing has historically been the most damaged in such storms, contributing disproportionately to community risk. This risk posed by severe wind is not well understood, nor are the optimal strategies for managing, and potentially reducing, this risk. In this hazard context, this project was initiated based on a joint proposal developed by Queensland Fire and Emergency Services (QFES), Geoscience Australia and the six coastal local governments in SEQ in January 2020. The objective was to gain an improved understanding of the wind risks in this region and to develop actionable information that could inform future strategies to manage and reduce risk in these areas, with broader application to other local government areas. The project proved to be of great interest to a broader range of stakeholders, including the insurance industry, some of whom became formal partners, while others participated as observers. </div><div><br></div><div>The management of wind risk requires a sound evidence base for decision makers. While the information developed in this project has significant uncertainties, the outcomes are considered a representative view of wind risk in a coastal region that is home to nearly 60% of the Queensland population. The work has developed an improved understanding of the three primary risk elements of wind hazard, residential exposure and vulnerability. This has been achieved through a broad collaboration that has entailed the sharing of data, domain expertise and consensus building. This, in turn, has been translated into an assessment of scenario impacts, local scale risk, and the nuancing effects of resilience on the outcomes. An exploration was carried out of the effectiveness of a range of retrofit strategies directed at addressing the residential buildings in our communities that contribute the most wind risk in South East Queensland. The outcome are expected to be a valuable resource for all the project partners and stakeholders in the areas of planning, preparation, response, recovery and strategic mitigation.</div>

<div>The wind hazard climate in South East Queensland is a combination of tropical cyclones, thunderstorms and synoptic storms. This dataset provides estimated average recurrence interval (ARI) or annual exceedance probability (AEP) wind speeds over the region, based on an evaluation of observational (thunderstorms and synoptic winds) and simulated data (tropical cyclones). </div><div><br></div><div>The tropical cyclone wind hazard was evaluated using Geoscience Australia's Tropical Cyclone Risk Model (TCRM), which provides a spatial representation of the AEP wind speeds arising from tropical cyclones. Thunderstorm wind hazard was evaluated from analysis of observed wind gusts across South East Queensland, aggregated into a single 'superstation' to provide a single representative hazard profile for the region.</div><div><br></div><div>The resulting combined wind hazard estimates reflect the dominant source of wind hazard in South East Queensland for the most frequent events (exceedance probabilities greater than 1:50) is thunderstorm-generated wind gusts. For rarer events, with exceedance probabilities less than 1:200, TC are the dominant source of extreme gusts.&nbsp;</div><div><br></div><div>Local effects of topography, land cover and the built environment were incorporated via site exposure multipliers (Arthur & Moghaddam, 2021), which are based on the site exposure multipliers defined in AS/NZS 1170.2 (2021).</div><div><br></div><div>The local wind hazard maps were used to evaluate the financial risk to residential separate houses in South East Queensland.</div><div><br></div><div>Wind speeds are provided for average recurrence intervals ranging from 1 year to 10,000 years. No confidence intervals are provided in the data. </div>

<div>The Severe Wind Hazard Assessment for South East Queensland (SWHA-SEQ) analysed risk from severe wind events in a marginal tropical cyclone (TC) region with a large exposed population, and historical severe thunderstorm and TC impacts. SWHA-SEQ was a collaborative effort bringing together 15 partners across government, academia and the insurance sector to improve the collective understanding of wind risk in the region and inform future strategies to reduce this risk, in the context of climate change, urban planning and socio-economic status of the population. </div><div>The project involved enhancing the understanding of hazard, exposure and physical vulnerability to strengthen the comprehension of risk, including local-scale wind hazard from thunderstorm and TC wind gusts, and a semi-quantitative analysis of future wind hazard. Structural characteristics of residential housing stock were updated through a combination of street surveys, national databases of built assets and insurance portfolio statistics. Vulnerability models for residential houses including retrofitted models for 5 common house types were developed, alongside identification of key vulnerability factors for residential strata buildings.</div><div>Local governments are building on the outcomes of the project, with the City of Gold Coast using the project outcomes as the key evidence base for a A$100m investment over 7 years to advocate for uplift of building design criteria, targeted community engagement and resilience of City-owned infrastructure. Other local governments have conducted specific exercises exploring how they would manage a severe TC impact. The investments and activities directly flowing from SWHA-SEQ are testament to the partner engagement through the project. Presented at the 2024 Symposium on Hurricane Risk in a Changing Climate (SHRCC2024)