National Severe Wind Hazard Database  

Authors / CoAuthors

Arthur, W.C.

Abstract

Natural hazard data supports the nation to respond effectively to emergencies, reduce the threat natural hazards pose to Australia¿s national interests and address issues relating to community safety, urban development, building design, climate change and insurance. A baseline understanding of hazards, impacts and risk can help to enhance community resilience to extreme events and a changing environment. Probabilistic hazard and risk information provides planners and designers opportunity to investigate the cost and benefit of policy options to mitigate natural hazard impacts. Modelled disaster scenario information can enable disaggregation of probabilistic hazard to identify the most probable event contributing to hazard. Tropical cyclone return period wind hazard maps developed using the Tropical Cyclone Risk Model. The hazard maps are derived from a catalogue of synthetic tropical cyclone events representing 10,000 years of activity. Annual maxima are evaluated from the catalogue and used to fit a generalised extreme value distribution at each grid point. Wind multipliers are factors that transform regional wind speed to local wind speed, mathematically describing the influences of terrain, shielding and topographic effects. Local wind speeds are critical to wind-related activities that include hazard and risk assessment. The complete dataset is comprised of: - Stochastic tracks, wind fields and impact data; - Probabilistic wind speed data (hazard); - Site-exposure wind multipliers.

Product Type

dataset

eCat Id

101282

Contact for the resource

Keywords

( Sub-Topic Category )

• Tropical cyclone

• Published_Internal

Publication Date

Creation Date

2014-12-16T00:00:00

Security Constraints

Australian Government Security ClassificationSystem    

Classification - unclassified

Legal Constraints

Creative Commons Attribution 4.0 International Licence    

Access - license

Use - license

Status

Purpose

The stochastic tropical cyclone event set was created to underpin the probabilistic wind hazard maps for Australia, completed by GA. The maps allow State and Territory emergency managers to: - Determine the chance of a given wind speed or greater occurring at a location around Australia, due to tropical cyclones; - Prioritise communities for further detailed risk assessments; The site-exposure multipliers were created to relate regional-scale probabilistic wind hazard information to specific locations in the landscape, accounting for variations in topography, land cover and proximity of other structures, leading to a true representation of the wind speeds impacting structures at risk from severe wind. These issues are critical inputs to tropical cyclone severe wind planning and preparation activities being undertaken by the States and Territories. The site-exposure multipliers also have application in other wind-related risk assessment activities, for example bushfire spread modelling.

Maintenance Information

annually

Topic Category

climatologyMeteorologyAtmosphere

Series Information

Lineage

This work considers the severe wind hazard posed to the Australian mainland from tropical cyclone severe winds. The stochastic event set uses a statistical-parametric model of tropical cyclone behaviour (TCRM) to build a catalogue of TC events that are statistically similar to the observational record. TC tracks and intensity display significant autocorrelation, both temporally and spatially, and this is used to randomly generate tens of thousands of TC events. The model used to develop the catalogue is based on approaches used in the catastrophe risk modelling community for assessing risk from natural disasters (tropical cyclones, earthquakes, floods, etc.). Geoscience Australia developed the model as part of its suite of natural hazard models (including EQRM and ANUGA) to provide an evidence base to guide policy on emergency management in Australia. Regional wind speeds are affected by local conditions including terrain, shielding and topography. The local effects are quantified by wind multipliers that factor the regional wind speed to that expected at a site. The wind multipliers are numerically estimated from remote sensing techniques and digital elevation data using adaptations of formulae outlined in the Australian/New Zealand wind loading standard AS/NZS 1170.2:2011. This approach has been used in the national wind hazard and risk assessment.

Parent Information

Extents

[-44, -5, 100, 160]

Reference System

GDA94 (EPSG:4283)

Spatial Resolution

Spatial resolution 0.02 degrees

Service Information

Associations

Downloads and Links

Source Information