AIR Expands Europe Inland Flood Model, Updates UK Storm Surge Analysis

Catastrophe risk modeling firm AIR Worldwide announced it has released an expanded inland flood model for Central Europe to include the country of Poland in its model domain.

AIR also announced that it has updated the storm surge component of its coastal flood model for Great Britain, which is now incorporated into the AIR Extratropical Cyclone Model for Europe.

“The AIR Inland Flood Model for Central Europe is a fully stochastic, event-based flood model designed to support both individual risk selection and portfolio risk management,” said Cagdas Kafali, senior vice president of research for Boston-based AIR Worldwide, which is a Verisk business.

“It covers the effects of precipitation-induced flooding to insurable properties for both on- and off-floodplain locations,” he added.

Kafali said the the expanded model captures many of the complexities inherent in the flood-generation process, such as the space-time patterns of rainfall input; the effects of a highly variable climate, topography, soil type and other local factors that determine the amount of rainfall drained to the rivers; and the effects of snowmelt and man-made flood defenses on the flood risk.

The AIR Inland Flood Model for Central Europe features physically based rainfall-runoff modeling and hydraulic modeling of detailed river networks extending more than 250,000 kilometers in the modeled countries. The model includes more than 45,000 stream links and unit catchments located partially or entirely within Austria, Czech Republic, Germany, Poland, and Switzerland.

AIR also announced a major update to the storm surge component of the AIR Coastal Flood Model for Great Britain, including new storm surge events for the stochastic catalog and an expanded model domain that includes all coastal areas of England and Wales.

Additionally, the storm surge peril update incorporates detailed coastal sea defenses, such as levees and sea walls and their probability of failure, as well as updated damage functions, said AIR, noting that the updated coastal flood model for Great Britain will now be incorporated into the AIR Extratropical Cyclone Model for Europe.

Including storm surge in the United Kingdom as a new sub-peril in the AIR Extratropical Cyclone Model for Europe enables the model to realistically account for the link between intense storm systems and the associated coastal surge effects they generate.

“The updated extratropical cyclone model explicitly captures damage and loss associated with winds from large-scale windstorms in 22 European countries,” Kafali continued.

“With approximately 10 to 15 percent of coastline less than 5 meters above sea level, the UK is one of the countries in Europe most vulnerable to coastal flooding,” he said.

“The new surge sub-peril can capture the effects of storm surge flooding on insured properties on the coasts of England and Wales and help address the wide spectrum of storm surge risk management needs of all stakeholders throughout the insurance and reinsurance industries, while accounting for the insurance policy conditions specific to the modeled regions of Great Britain.”

The AIR Inland Flood Model for Central Europe and the AIR Extratropical Cyclone Model for Europe are currently available in the Touchstone®, Touchstone ReÔ, and CATRADER® catastrophe risk management systems.

Source: AIR Worldwide