Catastrophe Risk Modeling

Catastrophe risk modeling estimates the probability distribution of losses from natural perils, such as hurricanes, earthquakes, and floods, by simulating large stochastic sets of plausible events and pushing each through hazard, exposure, vulnerability, and financial modules. It exists because catastrophe losses are rare, severe, and spatially correlated, so historical loss data alone cannot reveal the tail risk that insurers and governments must plan for; instead the model synthesizes thousands of years of possible events. Patricia Grossi and Howard Kunreuther's 2005 volume systematized the four-module structure and its use in managing risk, while Kirsten Mitchell-Wallace and colleagues' 2017 practitioner's guide is the standard modern reference for how the industry builds and uses these models. The defining output is the loss exceedance curve, from which average annual loss, return-period losses, and probable maximum loss are read. Catastrophe models are the engine of property catastrophe insurance, reinsurance pricing, and increasingly public disaster-risk finance. They turn the physics of rare hazards into the financial metrics needed to price and transfer extreme risk.