Indirect cost and benefit assessment of climate adaptation strategies for extreme wind events in Queensland

The intensity of tropical cyclones and severe storms are likely to increase due to climate change. Brisbane and the northeast coast of Queensland are regions where design wind specifications may be inadequate under either current or likely future climate conditions. An appropriate adaptation strategy may be one that increase wind classifications for new houses leading to reduced vulnerability of new construction. The present paper will assess the damage risks, adaptation costs and cost-effectiveness of this adaptation measures for residential construction in Cairns, Townsville, Rockhampton and South East Queensland assuming time-dependent changes in frequency and intensity of cyclonic and non-cyclonic winds to 2100. Loss functions are also developed for direct and indirect losses. It was found that increasing design wind loads for new houses in Brisbane and South East Queensland will lead to a net benefit (net present value NPV) of up to $10.5 billion by 2100 assuming a discount rate of 4%, which includes approximately 95% of direct benefit and 5% of indirect benefit. The benefits are highest for Brisbane due to its large population and high vulnerability of existing residential construction, and have 90-100% likelihood to achieve a net benefit by 2100.