Karen Clark & Company released its new Severe Convective Storm Reference Model. AIR Worldwide Worldwide has introduced a new inland flood model for Japan, along with enhancements to its Japan typhoon model.

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Karen Clark & Company released its new Severe Convective Storm (SCS) Reference Model. The model is based on advanced scientific modeling techniques and has been validated with high resolution insurer claims data.

The new model is based on a physical modeling methodology and high resolution atmospheric data that more accurately capture the dynamics of this peril than existing methods, KCC said, adding that the model shows that expected average annual aggregate losses are now approaching $20 billion—larger than hurricane and earthquake combined.

The KCC SCS Reference Model is a multi-peril model (MPM), and the hazards of hail versus tornadoes and straight-line winds are simulated separately. The model shows that hail dominates the SCS peril, accounting for nearly 70 percent of annual losses on average.

Along with a stochastic catalog of over 33,000 events used for pricing and reinsurance decision making, the model includes over 100 historical SCS events. Insurers use the historical events to benchmark the model against their actual losses to verify the model accuracy.

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Catastrophe modeling firm AIR Worldwide has introduced a new inland flood model for Japan, along with enhancements to its Japan typhoon model.

These models are part of Version 5.1 of AIR’s comprehensive catastrophe modeling software platform, Touchstone^®. AIR Worldwide is a Verisk (Nasdaq:VRSK) business.

The AIR Inland Flood Model for Japan explicitly simulates the effects of on- and off-plain inland flooding from sources other than tropical cyclones. Non-tropical systems that trigger inland flooding account for 40 percent of flood losses in Japan. The new probabilistic model captures the complexities of the flood peril in an area of more than 377,000 square kilometers divided into over 20,000 unit catchments for a river network exceeding 100,000 km in length—and takes flood defenses into consideration. The model was calibrated and validated using observational data based on river flows at nearly 1,000 locations, as well as lake and dam storage data from more than 2,000 locations.

The model generates flood events by way of a large-scale hydrological model that simulates continuous surface runoff and river flows using a method that learns the patterns of precipitation from observed tropical cyclone and non-tropical cyclone systems. The model takes into account river shape, dams, levees, and other structures when computing discharge at each location along the river network. Preexisting conditions—including lake and dam storage and soil saturation—that can exacerbate flood conditions are explicitly accounted for.

The new inland flood model can be used with AIR’s Japan typhoon model to develop a complete understanding of flood risk for Japan. This model, updated to include a completely new typhoon-induced precipitation module, also captures the risk from wind and storm surge.

Both Japan models are released in Touchstone 5.1, which also features significant enhancements to the geospatial module.

Sources: Karen Clark & Co., AIR Worldwide