LONDON, March 6, 2025 - WTW (NASDAQ: WTW), a leading global advisory, broking, and solutions company, today announced the continuation of their long-standing partnership with the Karlsruhe Institute of Technology (KIT), in collaboration with NASA’s Disasters Program and the NASA Langley Research Center, to improve the understanding and modelling of hail risk. Building on more than a decade of collaboration, this new phase focuses on using state-of-the-art datasets and research to address the challenges posed by hailstorms, with particular focus on the impacts of climate change.
Hailstorms rank among the costliest severe weather perils, particularly in Europe, where recent years have seen significant insured losses. As climate change modifies hail formation processes and adds complexity to this peril, understanding how hailstorm characteristics—such as frequency, intensity, and spatial distribution—might evolve has become a top priority for (re)insurers and researchers alike. This collaboration also builds on the success of the original Willis European hail model, the first stochastic hail model to cover the entire European region. Since its introduction in 2014, the model has become a vital tool for hail risk estimation and pricing, widely adopted by (re)insurers across Europe.
In the latest phase of the collaboration, the previous Willis European hail model will be updated and substantially improved. This will be achieved through a refined and extended time series of overshooting cloud top detections from satellites by NASA, which serve as proxies for severe storms / hailstorms, as well as a new model setup for hail hazard assessment. In addition, researchers will explore how climate factors influence hailstorm characteristics, including hailstone size, frequency, and damage potential. Combining advanced simulations, high-resolution satellite data, and detailed trend analysis of ambient conditions, the project aims to deliver new insights into the spatial and temporal distribution of hail risks across Europe. These efforts will support the (re)insurance industry in better anticipating and managing hail-related risks in a rapidly changing climate.
“Hailstorms are a growing concern for the (re)insurance industry, particularly as climate change introduces new uncertainties around their behavior,” said Dr. Daniel Bannister, Weather & Climate Risks Research Lead at WTW. “Our continued collaboration with KIT and NASA ensures we remain at the forefront of scientific research, enabling us to provide (re)insurers with the insights they need to respond to this complex peril.”
“Our collaboration with WTW and NASA allows us to integrate cutting-edge science and innovative methods into business and economic sectors, impacting the public at large," said Prof. Michael Kunz, leader of the Atmospheric Risks working group at KIT. "It's crucial to deepen our understanding of how climate change influences hail formation and how this, in turn, translates into risk.”
“With state-of-the-art identification techniques we can quantify severe storm distribution and frequency with an exceptional level of consistency and persistence that’s only granted by satellite measurements,” said Benjamin Scarino, a Research Scientist at NASA’s Langley Research Center. “Long-term satellite data records allow us to provide the (re)insurance industry, project partners, and the research community with valuable insights into severe storm activity and risk.”
At WTW (NASDAQ: WTW), we provide data-driven, insight-led solutions in the areas of people, risk and capital. Leveraging the global view and local expertise of our colleagues serving 140 countries and markets, we help organizations sharpen their strategy, enhance organizational resilience, motivate their workforce and maximize performance.
Working shoulder to shoulder with our clients, we uncover opportunities for sustainable success—and provide perspective that moves you.
KIT – The Research University in the Helmholtz Association – is the only scientific institution of its kind in Germany. Like no other institution in the German science sector does it live the interconnection of university and non-university research, from findings-driven fundamental research to applied research in combination with research-oriented teaching.
As one of eleven universities of excellence in Germany, we make significant contributions in the fields of energy, mobility, information, climate, and the environment.
Learn more about the NASA Disasters Program at Advancing Science for Disaster Resilience