We’re delighted to be back under our original name, Willis Research Network, within the WTW family – small but important reminder of the continuity and legacy of a network that has now been driving innovation in risk and resilience for nearly two decades.

This quarter we look at themes that go to the heart of today’s risk conversation. Twenty years after Hurricane Katrina, we explore whether the industry is truly prepared for the next $100 billion loss, a question that is less about “if” than “when.” At the other end of the spectrum, the sudden collapse of Switzerland’s Blatten Glacier is a stark signal of how fragile our physical systems are becoming, and the implications of climate volatility for underwriting, accumulation management and client resilience.

The mid-year Natural Catastrophe Review provides grounding in the numbers and trends shaping the season so far. It includes new insights on wildfire modelling and European windstorm, two areas where recent events have shown the need to continually test and refine our understanding of exposure.  Our Natural Catastrophe Seminar Series brings these issues into focus for the market. Our most recent session on 25 September focused on the future of urban wildfire risk, whilst on 6 November we will shine a light on severe convective storms, long treated as a secondary peril but increasingly a primary driver of U.S. loss. It is an important opportunity to hear directly from experts on what this shift means for risk management, reinsurance strategy and pricing.

Finally, we turn to demographics and human vulnerability. Ageing populations, climate driven migration and shifting urban resilience are reshaping exposure in ways that touch almost every line of business. Understanding these changes is not just about managing liabilities. It is about anticipating how risk itself will evolve and ensuring that the industry is ready to respond with solutions that strengthen resilience.

We trust this edition provides useful context and supports your continued efforts to understand and manage an increasingly complex global risk environment.

The Willis Research Network

Table of Contents

1. 01

   20 years after Hurricane Katrina, are insurers ready for a completely different kind of $100+ billion disaster?

   Hurricane Katrina reshaped disaster risk management, but 20 years later, we still plan for the last crisis, not the next one. Here are 5 reasons future $100+ billion catastrophes could be far more complex.

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2. 02

   Natural Catastrophe Program 2025

   The latest WTW Natural Catastrophe seminar will shine a light on sever convective storms, traditionally seen as a secondary peril but increasing becoming a key driver of loss in the US. Join is us we discuss steps we ought to take to prepare for this heightened risk

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3. 03

   Kamchatka Earthquake: A reminder of tsunami risk along the U.S. west coast

   The largest earthquake globally since 2011 caused minimal damage, but highlights the persistent and often overlooked tsunami risk facing the U.S. West Coast..

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4. 04

   Climate change and the rising cost of UK home insurance

   Wind, flood and subsidence risks in the UK are evolving due to climate change and becoming more costly for home insurers.

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5. 05

   Long waves and tall buildings: Site effect considerations in catastrophe models following the Myanmar earthquake

   A Mw7.7 earthquake in Myanmar caused intense shaking and damage locally, as well as a tower collapse in Bangkok more than 1,000 km away. Do catastrophe models account for these long-distance effects?

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6. 06

   What the Blatten glacier collapse tells us about risk in a changing world

   The collapse of Birch Glacier buried most of Blatten, highlighting how climate change is reshaping risk. As global temperatures increase, businesses can stay ahead by detecting and managing emerging threats.

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7. 07

   “Build Back Better?”: Demographic Decline and the Future of Protection Gaps

   From climate risk to care homes, aging and declining populations are reshaping the risk landscape and with it the protection models that underpin global resilience.

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8. 08

   From Risk to Resilience: How Communities and Insurance Markets Are Redefining Wildfire Risk Mitigation

   In the face of escalating wildfire devastation across the western United States, a quiet revolution is taking root – not in Washington, not in Silicon Valley, but in the neighbourhoods most at risk. These communities are no longer waiting for help to arrive. They are building resilience from the ground up.

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9. 09

   Storm Éowyn: A timely reminder of the potential power of European windstorms

   Storm Éowyn hit north western Europe in January 2025 with record gusts in western Ireland. Does this signal a climate change driven new normal for European windstorm intensity?

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10. 10

    The Los Angeles fires: 3 questions you must ask about wildfire models

    The devastating Los Angeles fires of January 2025 illustrate why insurers must cast a critical eye toward wildfire models, starting by asking these three questions.

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