Verisk Bushfire Model for Australia

Scope

Major update introduces a new, robust methodology of modeling wildfire and incorporates recent data and science to provide clients with vastly improved information for analysis.

General model updates

Hazard

Spatial constraint removed from fire cluster definition – individual fires occurring within 7 days of each other are clustered into events.
New intensity parameter: flame length. Flame length is determined from topography, wind speed and direction, ground and canopy fuel, and fuel moisture.
Ignition locations for individual fires are determined from historical patterns and current fuel availability.
Fire spread is dependent on wind data, fire suppression activities, population density, impervious surface area, and distance from wildland-urban interface. Spread by wind-blown embers is explicitly modeled, and structures are included as potential fuel for fires. The direction of spread changes as the wind direction shifts during the lifetime of a fire.
To present a near-present view of the hazard, climate trends and the extent to which they affect fire area, fire size, and ignition date are uniquely accounted for in each biogeographic region.

Vulnerability

New damage functions
Updated height bands
Updated fuel layers with data from multiple government agencies
Spatial-temporal variation in Building Code Requirements

Catalogs and event sets

Stochastic catalog(s)
- Updated 10,000-year and 100,000-year catalogs
- All event IDs are new.
Historical event set
- Six new events
  - 2016 Yarloop
  - 2017 Sir Ivan and Carwoola
  - 2018 Tathra
  - 2019 Bunyip
  - 2019-2020 Bushfires
  - 2021 Wooroloo/Perth Hills Bushfire

Touchstone-specific updates

Event Description
- New tag for moisture index
- New tag for El Niño/La Niña year
New support for specialized risk types
- Marine
Support for additional construction and occupancy codes
- Construction: Updated to 128 classes total (including 20 marine asset classes)
- Occupancy: Updated to 110 classes total (including 12 marine storage classes)
Support for six new secondary risk characteristics
- Deck
- Defensible space
- Gutter
- Roof vents
- Rent vent size
- Wall siding fire rating

Touchstone Re-specific updates

Updated Industry Exposure Database
- Vintage updated to 2024
- Resolution updated to 90 m