A Simple Loss Model for European Windstorms

European windstorms are significant drivers of economic damage and impact various sectors such as aviation, forestry, energy, and agriculture. Understanding and modeling the associated losses and risks are crucial to prepare and adapt for the present and future impacts. A simple model is developed to estimate insurance losses using ERA5 wind gust data (31 km horizontal resolution) and LitPop asset values. We also test the sensitivity of the model to another exposure dataset based on population disaggregation of the countrywide gross domestic product. The model employs a cubic damage function with a 20m/s threshold, calibrated to a European annual average loss of 3 billion Euros. It is compared to vendor models annual average and event-based loss estimates, showing good performance overall but discrepancies at regional levels. The model underestimates the annual average losses over Germany and France while overestimating the UK-IE aggregated losses. Differences stem from an oversimplified damage function, unaccounted regional vulnerabilities and the hazard component. Exposure datasets minimally affect average annual losses and return periods of large losses. Limitations include ERA5's capability to represent individual storm footprints such as the Great Storm of 1987 and others. Moreover, a line of business based damage function approach demonstrates considerable improvements in the regional AALs as well as the extremes. High-resolution climate model simulations (12 km horizontal resolution) using multi-ensemble UKCP18 show consistent results.