Conclusions

The studies presented here show that climate change may lead to increased risk in European Windstorm losses by 2050 and later.

CoreLogic’s 2010 study Activity Of Catastrophic Windstorm Events In Europe In The 21st Century assessed the impact of climate change on windstorms and is in broad agreement with subsequent studies with respect both to hazard and loss. Studies indicate that climate change will lead to a tri-polar change in the tracks of European windstorms, creating an increased risk over western Europe. Losses would increase under both moderate and relatively strong climate change by 2050, with annualised values increasing by around 20% according to some studies.

However, even with the increased accuracy of the latest CMIP6 models, inter-model uncertainty remains very high, swamping the projected changes in mean loss. For this reason, CoreLogic recommends that the impact of natural variability under current climate conditions is of greater importance to risk assessment.

A major contributor to this natural variability is the North Atlantic Oscillation (NAO), a large-scale atmospheric oscillation which manifests as the seesaw of pressure anomaly difference between the Azores High and Iceland Low. Its strength is expressed in the form of the NAO Index (NAOI), which in one of its most common formats is based on measurements in the north-eastern and south-eastern parts of the North Atlantic Ocean, typically at Reykjavik and Lisbon. CoreLogic’s Eurowind™ includes separate event sets for the positive and negative phases of the NAO, enabling risk modellers to capture this source of uncertainty on loss.